Publications by authors named "Zhongfa Liu"

59 Publications

Core-shell microencapsulation of curcumin in PLGA microparticles: programmed for application in ovarian cancer therapy.

Artif Cells Nanomed Biotechnol 2018 9;46(sup3):S481-S491. Epub 2018 Oct 9.

a Department of Precision Machinery and Precision Instrumentation , University of Science and Technology of China , Hefei , Anhui , People's Republic of China.

In our study, we have established a novel liquid-driven co-flow focusing (LDCF) process to fabricate curcumin (CUR)-loaded poly (lactic-co-glycolic acid) (PLGA) microparticles (CPMs). LDCF-CPMs of size 20.26 ± 2.37 μm have high encapsulation efficiency (>70%) and were intended for application in ovarian cancer by intraperitoneal (IP) administration. LDCF-CPMs have smooth surface with narrow size distribution and a core-shell structured verified by confocal microscopy which can be precisely controlled by changing the flow rates of focusing, outer and inner phases. The LDCF-CPMs reveal the physiochemical stability with sustained release profile corresponding to 95% CUR release over a period of 14 days in an in vitro release medium. Moreover, LDCF-CPMs were testified for cytotoxicity against SKOV-3 ovarian cancer cell lines and peritoneal delivery advantages by animal experiments. The pharmacokinetics of LDCF-CPMs in rats following IP injection shows slow systemic absorption with mean residence time (MRT) of 13.54 h in comparison with 9.82 and 6.74 h for SE-CPMs and free CUR, respectively. In addition, IP delivery of CUR can expose the ovarian tumour to higher concentration for a longer duration by programming the thickness of the shell. The study provides compelling evidence for LDCF-CPMs having high therapeutic opportunity in the treatment of peritoneal cancers, such as ovarian, that reside in the peritoneal cavity.
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http://dx.doi.org/10.1080/21691401.2018.1499664DOI Listing
June 2019

A phase 1 trial of the HDAC inhibitor AR-42 in patients with multiple myeloma and T- and B-cell lymphomas.

Leuk Lymphoma 2017 Oct 7;58(10):2310-2318. Epub 2017 Mar 7.

f Division of Hematology, Department of Internal Medicine , The Ohio State University , Columbus , OH , USA.

Histone deacetylase inhibitors (HDACi) have proven activity in hematologic malignancies, and their FDA approval in multiple myeloma (MM) and T-cell lymphoma highlights the need for further development of this drug class. We investigated AR-42, an oral pan-HDACi, in a first-in-man phase 1 dose escalation clinical trial. Overall, treatment was well tolerated, no DLTs were evident, and the MTD was defined as 40 mg dosed three times weekly for three weeks of a 28-day cycle. One patient each with MM and mantle cell lymphoma demonstrated disease control for 19 and 27 months (ongoing), respectively. Treatment was associated with reduction of serum CD44, a transmembrane glycoprotein associated with steroid and immunomodulatory drug resistance in MM. Our findings indicate that AR-42 is safe and that further investigation of AR-42 in combination regimens for the treatment of patients with lymphoma and MM is warranted.

Trial Registration: http://clinicaltrials.gov/ct2/show/NCT01129193.
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http://dx.doi.org/10.1080/10428194.2017.1298751DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5489371PMC
October 2017

Preclinical Pharmacokinetics Study of R- and S-Enantiomers of the Histone Deacetylase Inhibitor, AR-42 (NSC 731438), in Rodents.

AAPS J 2016 05 4;18(3):737-45. Epub 2016 Mar 4.

College of Pharmacy, The Ohio State University, 500 W. 12th Avenue, Columbus, Ohio, 43210, USA.

AR-42, a new orally bioavailable, potent, hydroxamate-tethered phenylbutyrate class I/IIB histone deacetylase inhibitor currently is under evaluation in phase 1 and 2 clinical trials and has demonstrated activity in both hematologic and solid tumor malignancies. This report focuses on the preclinical characterization of the pharmacokinetics of AR-42 in mice and rats. A high-performance liquid chromatography-tandem mass spectrometry assay has been developed and applied to the pharmacokinetic study of the more active stereoisomer, S-AR-42, when administered via intravenous and oral routes in rodents, including plasma, bone marrow, and spleen pharmacokinetics (PK) in CD2F1 mice and plasma PK in F344 rats. Oral bioavailability was estimated to be 26 and 100% in mice and rats, respectively. R-AR-42 was also evaluated intravenously in rats and was shown to display different pharmacokinetics with a much shorter terminal half-life compared to that of S-AR-42. Renal clearance was a minor elimination pathway for parental S-AR-42. Oral administration of S-AR-42 to tumor-bearing mice demonstrated high uptake and exposure of the parent drug in the lymphoid tissues, spleen, and bone marrow. This is the first report of the pharmacokinetics of this novel agent, which is now in early phase clinical trials.
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http://dx.doi.org/10.1208/s12248-016-9876-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5256597PMC
May 2016

Coaxial Electrospray of Curcumin-Loaded Microparticles for Sustained Drug Release.

PLoS One 2015 24;10(7):e0132609. Epub 2015 Jul 24.

Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui, 230027, People's Republic of China; Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio, 43210, United States of America.

Curcumin exhibits superior anti-inflammatory, antiseptic and analgesic activities without significant side effects. However, clinical dissemination of this natural medicine is limited by its low solubility and poor bio-availability. To overcome this limitation, we propose to encapsulate curcumin in poly(lactic-co-glycolic acid) (PLGA) microparticles (MPs) by an improved coaxial electrospray (CES) process. This process is able to generate a stable cone-jet mode in a wide range of operation parameters in order to produce curcumin-loaded PLGA MPs with a clear core-shell structure and a designated size of several micrometers. In order to optimize the process outcome, the effects of primary operation parameters such as the applied electric voltages and the liquid flow rates are studied systemically. In vitro drug release experiments are also carried out for the CES-produced MPs in comparison with those by a single axial electrospray process. Our experimental results show that the CES process can be effectively controlled to encapsulate drugs of low aqueous solubility for high encapsulation efficiency and optimal drug release profiles.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0132609PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4514801PMC
May 2016

Fenretinide Perturbs Focal Adhesion Kinase in Premalignant and Malignant Human Oral Keratinocytes. Fenretinide's Chemopreventive Mechanisms Include ECM Interactions.

Cancer Prev Res (Phila) 2015 May 24;8(5):419-30. Epub 2015 Feb 24.

Division of Oral Maxillofacial Pathology and Radiology, College of Dentistry, The Ohio State University, Columbus, Ohio. The Ohio State University Comprehensive Cancer, Columbus, Ohio.

The membrane-associated protein, focal adhesion kinase (FAK), modulates cell-extracellular matrix interactions and also conveys prosurvival and proliferative signals. Notably, increased intraepithelial FAK levels accompany transformation of premalignant oral intraepithelial neoplasia (OIN) to oral squamous cell carcinoma (OSCC). OIN chemoprevention is a patient-centric, optimal strategy to prevent OSCC's comorbidities and mortality. The cancer chemopreventive and synthetic vitamin A derivative, fenretinide, has demonstrated protein-binding capacities, for example, mTOR- and retinol-binding protein interactions. These studies used a continuum of human oral keratinocytes (normal-HPV E6/E7-transduced-OSCC) to assess potential fenretinide-FAK drug protein interactions and functional consequences on cellular growth regulation and motility. Molecular modeling studies demonstrated that fenretinide has approximately 200-fold greater binding affinity relative to the natural ligand (ATP) at FAK's kinase domain. Fenretinide also shows intermediate binding at FAK's FERM domain and interacts at the ATP-binding site of the closest FAK analogue, PYK2. Fenretinide significantly suppressed proliferation via induction of apoptosis and G2-M cell-cycle blockade. Fenretinide-treated cells also demonstrated F-actin disruption, significant inhibition of both directed migration and invasion of a synthetic basement membrane, and decreased phosphorylation of growth-promoting kinases. A commercially available FAK inhibitor did not suppress cell invasion. Notably, although FAK's FERM domain directs cell invasion, FAK inhibitors target the kinase domain. In addition, FAK-specific siRNA-treated cells showed an intermediate cell migration capacity; data which suggest cocontribution of the established migrating-enhancing PYK2. Our data imply that fenretinide is uniquely capable of disrupting FAK's and PYK2's prosurvival and mobility-enhancing effects and further extend fenretinide's chemopreventive contributions beyond induction of apoptosis and differentiation.
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http://dx.doi.org/10.1158/1940-6207.CAPR-14-0418DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4417376PMC
May 2015

Oral administration of nano-emulsion curcumin in mice suppresses inflammatory-induced NFκB signaling and macrophage migration.

PLoS One 2014 4;9(11):e111559. Epub 2014 Nov 4.

Division of Rheumatology and Immunology, Wexner Medical Center at The Ohio State University, Columbus, Ohio, United States of America; Department of Internal Medicine, Wexner Medical Center at The Ohio State University, Columbus, Ohio, United States of America.

Despite the widespread use of curcumin for centuries in Eastern medicine as an anti-inflammatory agent, its molecular actions and therapeutic viability have only recently been explored. While curcumin does have potential therapeutic efficacy, both solubility and bioavailability must be improved before it can be more successfully translated to clinical care. We have previously reported a novel formulation of nano-emulsion curcumin (NEC) that achieves significantly greater plasma concentrations in mice after oral administration. Here, we confirm the immunosuppressive effects of NEC in vivo and further examine its molecular mechanisms to better understand therapeutic potential. Using transgenic mice harboring an NFκB-luciferase reporter gene, we demonstrate a novel application of this in vivo inflammatory model to test the efficacy of NEC administration by bioluminescent imaging and show that LPS-induced NFκB activity was suppressed with NEC compared to an equivalent amount of curcumin in aqueous suspension. Administration of NEC by oral gavage resulted in a reduction of blood monocytes, decreased levels of both TLR4 and RAGE expression, and inhibited secretion of MCP-1. Mechanistically, curcumin blocked LPS-induced phosphorylation of the p65 subunit of NFκB and IκBα in murine macrophages. In a mouse model of peritonitis, NEC significantly reduced macrophage recruitment, but not T-cell or B-cell levels. In addition, curcumin treatment of monocyte derived cell lines and primary human macrophages in vitro significantly inhibited cell migration. These data demonstrate that curcumin can suppress inflammation by inhibiting macrophage migration via NFκB and MCP-1 inhibition and establish that NEC is an effective therapeutic formulation to increase the bioavailability of curcumin in order to facilitate this response.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0111559PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4219720PMC
June 2015

A high-throughput quantification method of curcuminoids and curcumin metabolites in human plasma via high-performance liquid chromatography/tandem mass spectrometry.

J Chromatogr B Analyt Technol Biomed Life Sci 2014 Feb 15;949-950:70-8. Epub 2014 Jan 15.

College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA. Electronic address:

Curcuminoids, a mixture of curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC), have shown a variety of clinical benefits for several human chronic diseases including osteoarthritis, rheumatoarthritis, and type II diabetes. However, the oral bioavailability of curcumin is extremely low due to its avid metabolism to curcumin O-glucuronide (COG), curcumin O-sulfate (COS), tetrahydrocurcumin (THC), and other minor metabolites. This paper reports a unique liquid chromatography/tandem mass spectrometry (LC-MS/MS) method to quantify curcumin, DMC, BDMC, COG, COS, and THC simultaneously in human plasma. These compounds were extracted with ethyl acetate from human plasma, separated on a BetaBasic-8 column, and monitored on a triple quadruple mass spectrometer coupled with API electrospray under a negative ion mode. The linearity of these respective curcuminoids and curcumin metabolites was shown in the range of 2-1000ng/mL with 85-115% accuracy and ≤20% precision in human plasma. This method was validated according to the US FDA GLP analytic criteria and applied to characterize the pharmacokinetics of curcumin, COG, and COS in human plasma after an oral dose of bioavailable curcumin (nanoemulsion curcumin).
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http://dx.doi.org/10.1016/j.jchromb.2013.12.039DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4188440PMC
February 2014

Phase I study of GTI-2040, a ribonucleotide reductase antisense, with high dose cytarabine in patients with relapsed/refractory acute myeloid leukemia.

Leuk Lymphoma 2014 Jun 1;55(6):1332-6. Epub 2013 Nov 1.

Division of Hematology, Department of Medicine.

We hypothesized that GTI-2040, a 20-mer oligonucleotide complementary to the R2 subunit mRNA of ribonucleotide reductase, combined with high dose cytarabine (HiDAC) would result in enhanced cytotoxicity by favoring Ara-CTP DNA incorporation. In a phase I dose escalation trial, adults (≥ 60 years) with refractory or relapsed acute myeloid leukemia (AML) received daily HiDAC plus infusional GTI-2040. Using a novel assay, evidence of intracellular drug accumulation and target R2 down-regulation was observed. GTI-2040/HiDAC can be administered safely. However, with no complete remissions observed, alternative doses and schedules may need to be investigated to achieve clinical activity in older patients with AML.
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http://dx.doi.org/10.3109/10428194.2013.838764DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4298748PMC
June 2014

Serum levels of intravitreal bevacizumab after vitrectomy, lensectomy and non-surgical controls.

Curr Eye Res 2013 Jul 2;38(7):761-6. Epub 2013 Apr 2.

Department of Ophthalmology & Visual Science, College of Medicine, The University of Arizona, Tucson, AZ, USA .

Purpose: To determine serum level differences of intravitreally-placed bevacizumab after vitrectomy and lensectomy-vitrectomy and to compare these with non-operated eyes in a rabbit model.

Methods: Five Dutch-belted rabbits underwent pars plana vitrectomy (PPV), five rabbits underwent pars plana lensectomy (PPL) and five rabbits served as non-surgical controls. Twelve days following the surgical procedures, each operated eye underwent an intravitreal injection consisting of 1.25 mg/0.05 mL bevacizumab. Serum levels from each rabbit were drawn on days 2, 4, 7, 10, 14, 21, 28 and 35 and were measured with ELISA immunoassay.

Results: The average peak serum concentration (Cmax) was highest for the PPL group (11.33 μg ± 3.48 mL), and was similar between the PPV (5.35 μg ± 2.69 mL) and non-surgical control groups (5.35 μg ± 0.69 mL). The average time to maximal plasma concentration (Tmax) in days was earliest for the PPL group (2.8 ± 0.47), followed by the PPV (5.6 ± 0.84) and non-surgical control groups (6.4 ± 0.71). The PPL group had higher serum levels than the other two groups until day 7 that was significant only at day 2 (p < 0.0001). After day 4, there were no significant differences or trends between any of the three groups. The half-life (T1/2) was fastest for the PPL group (1.41 ± 0.21 d) followed by the PPV (2.80 ± 3.35 d) and non-surgical control groups (6.69 ± 10.4 d).

Conclusions: Serum bevacizumab levels were initially elevated following lensectomy and vitrectomy compared to non-surgical eyes following intravitreal injection. The half-life of bevacizumab was prolonged in non-surgical eyes presumably due to a slower release from the vitreous cavity.
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http://dx.doi.org/10.3109/02713683.2013.763988DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3886184PMC
July 2013

LC-MS/MS quantification of a neuropeptide fragment kisspeptin-10 (NSC 741805) and characterization of its decomposition product and pharmacokinetics in rats.

J Chromatogr B Analyt Technol Biomed Life Sci 2013 May 4;926:1-8. Epub 2013 Mar 4.

College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA.

The kisspeptins are critical regulators of mammalian reproduction. Kisspeptin-10 ((45)YNWNSFGLRF-NH2(54), kisspeptin-112-121 or metastin 45-54, NSC 741805), an active fragment of kisspeptin, has been shown to be a potent stimulator of gonadotropin-releasing hormone and secretion of luteinizing hormone in both rodents and primates. This shorter peptide fragment may have clinical utility potential and it is important to characterize its pharmacokinetic property. Recently, the pharmacokinetics of both kisspeptin-54 and kisspeptin-10 were characterized in humans using a radioimmunoassay (RIA), which measures only the immunoreactive kisspeptin (kisspeptin-IR). In this study, a highly sensitive and specific LC-MS/MS assay was developed to quantify kisspeptin-10 levels in rat plasma. The lower limit of quantitation (LLOQ) was 0.5 ng/mL, the within-day and between-day coefficient of variations (CVs) ranged from 5.2 to 15.4% and 1.3 to 14.2%, and the accuracy values ranged from 98 to 114% and 99 to 105%, respectively. With this method, stability studies demonstrated that kisspeptin-10 degraded rapidly with decomposition half-lives of 6.8 min, 2.9 min and 1.7 min at 4 °C, 25 °C, and 37 °C, respectively. The principal decomposition product was characterized as the N-terminal tyrosine deleted kisspeptin-10 (46)NWDSFGLRF-NH2(54). Pharmacokinetic study in rats showed that low ng/mL kisspeptin-10 was detected in the first few minutes, and eliminated rapidly and became undetectable 30 min after intravenous (i.v.) bolus administration of 1.0 mg/kg kisspeptin-10.
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http://dx.doi.org/10.1016/j.jchromb.2013.02.027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3955120PMC
May 2013

Pharmacokinetics of phase I nevirapine metabolites following a single dose and at steady state.

Antimicrob Agents Chemother 2013 May 4;57(5):2154-60. Epub 2013 Mar 4.

School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Amherst, New York, USA.

Nevirapine is one of the most extensively prescribed antiretrovirals worldwide. The present analyses used data and specimens from two prior studies to characterize and compare plasma nevirapine phase I metabolite profiles following a single 200-mg oral dose of nevirapine in 10 HIV-negative African Americans and a steady-state 200-mg twice-daily dose in 10 HIV-infected Cambodians. Nevirapine was assayed by high-performance liquid chromatography (HPLC). The 2-, 3-, 8- and 12-hydroxy and 4-carboxy metabolites of nevirapine were assayed by liquid chromatography-tandem mass spectrometry (LC/MS/MS). Pharmacokinetic parameters were calculated by noncompartmental analysis. The metabolic index for each metabolite was defined as the ratio of the metabolite area under the concentration-time curve (AUC) to the nevirapine AUC. Every metabolite concentration was much less than the corresponding nevirapine concentration. The predominant metabolite after single dose and at steady state was 12-hydroxynevirapine. From single dose to steady state, the metabolic index increased for 3-hydroxynevirapine (P < 0.01) but decreased for 2-hydroxynevirapine (P < 0.001). The 3-hydroxynevirapine metabolic index was correlated with nevirapine apparent clearance (P < 0.001). These findings are consistent with induction of CYP2B6 (3-hydroxy metabolite) and a possible inhibition of CYP3A (2-hydroxy metabolite), although these are preliminary data. There were no such changes in metabolic indexes for 12-hydroxynevirapine or 4-carboxynevirapine. Two subjects with the CYP2B6 *6*6 genetic polymorphism had metabolic indexes in the same range as other subjects. These results suggest that nevirapine metabolite profiles change over time under the influence of enzyme induction, enzyme inhibition, and host genetics. Further work is warranted to elucidate nevirapine biotransformation pathways and implications for drug efficacy and toxicity.
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http://dx.doi.org/10.1128/AAC.02294-12DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3632909PMC
May 2013

Curcumin down-regulates DNA methyltransferase 1 and plays an anti-leukemic role in acute myeloid leukemia.

PLoS One 2013 13;8(2):e55934. Epub 2013 Feb 13.

Division of Hematology, Department of Internal Medicine, College of Medicine, The Ohio State University, Columbus, Ohio, United States of America.

Bioactive components from dietary supplements such as curcumin may represent attractive agents for cancer prevention or treatment. DNA methylation plays a critical role in acute myeloid leukemia (AML) development, and presents an excellent target for treatment of this disease. However, it remains largely unknown how curcumin, a component of the popular Indian spice turmeric, plays a role in DNA hypomethylation to reactivate silenced tumor suppressor genes and to present a potential treatment option for AML. Here we show that curcumin down-regulates DNMT1 expression in AML cell lines, both in vitro and in vivo, and in primary AML cells ex vivo. Mechanistically, curcumin reduced the expression of positive regulators of DNMT1, p65 and Sp1, which correlated with a reduction in binding of these transcription factors to the DNMT1 promoter in AML cell lines. This curcumin-mediated down-regulation of DNMT1 expression was concomitant with p15(INK4B) tumor suppressor gene reactivation, hypomethylation of the p15(INK4B) promoter, G1 cell cycle arrest, and induction of tumor cell apoptosis in vitro. In mice implanted with the human AML MV4-11 cell line, administration of curcumin resulted in remarkable suppression of AML tumor growth. Collectively, our data indicate that curcumin shows promise as a potential treatment for AML, and our findings provide a basis for future studies to test the clinical efficacy of curcumin - whether used as a single agent or as an adjuvant - for AML treatment.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0055934PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3572185PMC
August 2013

Pharmacokinetics and pharmacodynamics of midazolam after intravenous and intramuscular administration in alpacas.

Am J Vet Res 2013 Feb;74(2):294-9

Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA.

Objective: To determine pharmacokinetic and pharmacodynamic properties of midazolam after IV and IM administration in alpacas.

Animals: 6 healthy alpacas.

Procedures: Midazolam (0.5 mg/kg) was administered IV or IM in a randomized crossover design. Twelve hours prior to administration, catheters were placed in 1 (IM trial) or both (IV trial) jugular veins for drug administration and blood sample collection for determination of serum midazolam concentrations. Blood samples were obtained at intervals up to 24 hours after IM and IV administration. Midazolam concentrations were determined by use of tandem liquid chromatography-mass spectrometry.

Results: Maximum concentrations after IV administration (median, 1,394 ng/mL [range, 1,150 to 1,503 ng/mL]) and IM administration (411 ng/mL [217 to 675 ng/mL]) were measured at 3 minutes and at 5 to 30 minutes, respectively. Distribution half-life was 18.7 minutes (13 to 47 minutes) after IV administration and 41 minutes (30 to 80 minutes) after IM administration. Elimination half-life was 98 minutes (67 to 373 minutes) and 234 minutes (103 to 320 minutes) after IV and IM administration, respectively. Total clearance after IV administration was 11.3 mL/min/kg (6.7 to 13.9 mL/min/kg), and steady-state volume of distribution was 525 mL/kg (446 to 798 mL/kg). Bioavailability of midazolam after IM administration was 92%. Peak onset of sedation occurred at 0.4 minutes (IV) and 15 minutes (IM). Sedation was significantly greater after IV administration.

Conclusions And Clinical Relevance: Midazolam was well absorbed after IM administration, had a short duration of action, and induced moderate levels of sedation in alpacas.
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http://dx.doi.org/10.2460/ajvr.74.2.294DOI Listing
February 2013

In vivo quantification of active decitabine-triphosphate metabolite: a novel pharmacoanalytical endpoint for optimization of hypomethylating therapy in acute myeloid leukemia.

AAPS J 2013 Jan 22;15(1):242-9. Epub 2012 Nov 22.

Division of Pharmaceutics, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA.

Decitabine (DAC) is used for treatment of patients with myelodysplastic syndromes and acute myeloid leukemia (AML). Following cellular uptake, DAC is activated to DAC-triphosphate (TP) and incorporated into DNA. Once incorporated into the DNA, DAC-TP binds and inactivates DNA methyltransferases (DNMTs), thereby leading to hypomethylation and re-expression of epigenetically silenced tumor suppressor genes and ultimately antileukemia activity. However, direct evidence of in vivo DAC-TP occurrence in DAC-treated patients has been difficult to demonstrate due to a lack of suitable validated analytical methodology. Thus, we developed and validated a nonradioactive sensitive and specific LC-MS/MS assay for quantification of DAC-TP. The assay is linear from 50 to 1,000 nM and from 1 to 10 μM and has a lower limit of quantitation of 50 nM and a coefficient of variation for both within- and between-day precision <20%. Following DAC treatment, we detected DAC-TP in parental and DAC-resistant AML cells (in vitro) and bone marrow (BM) and spleen of normal and leukemic mice (in vivo). Downregulation of DNMTs and correlation of DAC-TP concentration with proteins involved in mechanisms of DAC resistance were also demonstrated. The clinical applicability of this method was proven by measuring DAC-TP level in BM and blood mononuclear cells from DAC-treated AML patients. Higher levels are seemingly associated with clinical response. Monitoring the DAC-TP intracellular level may serve as a novel pharmacological endpoint for designing more effective DAC-based regimens.
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http://dx.doi.org/10.1208/s12248-012-9427-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3535094PMC
January 2013

Reactivation of RASSF1A in breast cancer cells by curcumin.

Nutr Cancer 2012 12;64(8):1228-35. Epub 2012 Nov 12.

College of Pharmacy, Ohio State University, Columbus, Ohio 43210, USA.

Reactivation of tumor suppressor genes (TSGs) involved in carcinogenesis by nontoxic bioactive food component represents a promising strategy for cancer chemoprevention. Recently, curcumin has been demonstrated to inhibit a bacterial DNA methyltransferase (M. Sss I) activity, induce global DNA hypomethylation in leukemia cells, and reactivate several hypermethylation silenced genes in lung and prostate cancer cells. Herein, we demonstrated that curcumin can enhance the mRNA and protein levels of ras-association domain family protein 1A (RASSF1A), 1 hypermethylation-silenced TSG, and decrease its promoter methylation in breast cancer cells. Mechanistic study demonstrated that curcumin can decrease DNA methylation activity of nuclear extract and downregulate the mRNA and protein levels of DNMT1 in MCF-7 cells, which may be associated with curcumin-induced disruption of NF-κB/Sp1 complex bound to the promoter region of DNMT1. Altogether, this study reveals a novel molecular mechanism of curcumin as a chemo-preventive agent for breast cancer through hypomethylation reactivation of RASSF1A.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082258PMC
http://dx.doi.org/10.1080/01635581.2012.717682DOI Listing
May 2013

Pharmacokinetics of protocatechuic acid in mouse and its quantification in human plasma using LC-tandem mass spectrometry.

J Chromatogr B Analyt Technol Biomed Life Sci 2012 Nov 27;908:39-44. Epub 2012 Sep 27.

Zhejiang Cancer Research Institute, Zhejiang Cancer Hospital, Hangzhou, Zhejiang Province 310022, China.

Protocatechuic acid (PCA), a major microbial-mediated metabolite of anthocyanins, has significant anti-oxidative and anti-carcinogenic activities in vitro and in vivo; however, its pharmacokinetics remains largely unknown. In this report, a sensitive and rapid LC-MS/MS method was developed and validated for the measurement of PCA concentrations in both mouse and human plasma. This method showed a linearity of 1-1000ng/mL in both mouse and human plasma with a lower limit of quantification of 1ng/mL. The within-day and between-day coefficient of variation ranged from 1.18 to 11.8% and accuracy from 92 to 110%. The method was applied to characterize the pharmacokinetics of PCA in mice after oral administration of 50mg/kg PCA. PCA was absorbed rapidly with a half-life of 2.9min, reached a peak plasma level (C(max)) of 73.6μM at 5min, and remained detectable up to 8h with the initial elimination half-life of about 3min and a terminal half-life of 16min. The area under the plasma concentration-time curve (AUC(0→8h)) of PCA was 1456μMmin. The method was capable of detecting low ng/mL quantities of PCA in the plasma of patients with prostate cancer after an oral ingestion of 60g of black raspberry (BRB) powder. Because PCA is derived from the anthocyanins in BRB, our method provides a useful analytical tool to further investigate the metabolism of anthocyanins, and the pharmacology of PCA in future pre-clinical and clinical studies.
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http://dx.doi.org/10.1016/j.jchromb.2012.09.032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3538353PMC
November 2012

Triphala and its active constituent chebulinic acid are natural inhibitors of vascular endothelial growth factor-a mediated angiogenesis.

PLoS One 2012 24;7(8):e43934. Epub 2012 Aug 24.

Department of Pathology, Ohio State University, Columbus, Ohio, United States of America.

Triphala churna (THL) is a combination of three fruits that has been used for many years in India for the treatment of various diseases. There are now reports which indicate that THL can inhibit growth of malignant tumors in animals. However, the mechanisms by which THL mediates its anti-tumor actions are still being explored. Because vascular endothelial growth factor-A (VEGF) induced angiogenesis plays a critical role in the pathogenesis of cancer, we therefore investigated whether tumor inhibitory effects of THL or its active constituents are through suppression of VEGF actions. We herein report that THL and chebulinic (CI) present in THL can significantly and specifically inhibit VEGF induced angiogenesis by suppressing VEGF receptor-2 (VEGFR-2) phosphorylation. These results are of clinical significance as these inexpensive and non-toxic natural products can be used for the prevention and treatment of diseases where VEGF induced angiogenesis has an important role.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0043934PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3427174PMC
February 2013

A phase I study of prolonged infusion of triapine in combination with fixed dose rate gemcitabine in patients with advanced solid tumors.

Invest New Drugs 2013 Jun 31;31(3):685-95. Epub 2012 Jul 31.

Division of Medical Oncology, Department of Internal Medicine, College of Medicine, The Ohio State University and The Comprehensive Cancer Center, A454 Starling-Loving Hall, 320 West 10th Ave, Columbus, OH, 43210, USA.

Purpose: Prolonged exposure of cancer cells to triapine, an inhibitor of ribonucleotide reductase, followed by gemcitabine enhances gemcitabine activity in vitro. Fixed-dose-rate gemcitabine (FDR-G) has improved efficacy compared to standard-dose. We conducted a phase I trial to determine the maximum tolerated dose (MTD), safety, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary efficacy of prolonged triapine infusion followed by FDR-G.

Experimental Design: Triapine was given as a 24-hour infusion, immediately followed by FDR-G (1000 mg/m(2) over 100-minute). Initially, this combination was administered days 1 and 8 of a 21-day cycle (Arm A, triapine starting dose 120 mg); but because of myelosuppression, it was changed to days 1 and 15 of a 28-day cycle (Arm B, starting dose of triapine 75 mg). Triapine steady-state concentrations (Css) and circulating ribonucleotide reductase M2-subunit (RRM2) were measured.

Results: Thirty-six patients were enrolled. The MTD was determined to be triapine 90 mg (24-hour infusion) immediately followed by gemcitabine 1000 mg/m(2) (100-minute infusion), every 2 weeks of a 4-week cycle. DLTs included grade 4 thrombocytopenia, leukopenia and neutropenia. The treatment was well tolerated with fatigue, nausea/vomiting, fever, transaminitis, and cytopenias being the most common toxicities. Among 30 evaluable patients, 1 had a partial response and 15 had stable disease. Triapine PK was similar, although more variable, compared to previous studies using doses normalized to body-surface-area. Steady decline in circulating levels of RRM2 may correlate with outcome.

Conclusions: This combination was well tolerated and showed evidence of preliminary activity in this heavily pretreated patient population, including prior gemcitabine failure.
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http://dx.doi.org/10.1007/s10637-012-9863-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3646991PMC
June 2013

A liquid chromatography-tandem mass spectrometric method for quantification of curcumin-O-glucuronide and curcumin in human plasma.

J Chromatogr B Analyt Technol Biomed Life Sci 2012 Jul 26;900:89-93. Epub 2012 May 26.

Zhejiang Cancer Research Institute, Zhejiang Cancer Hospital, Hangzhou, Zhejiang Province 310022, China.

Curcumin is a widely used herbal medicine for various human diseases including inflammation and cancer. The demonstration and optimization of curcumin's activities in the clinical setting, however, have been compromised by its poor bioavailability and the lack of analytic methods to monitor its absorption. In this paper, we report the first validated liquid chromatography-tandem mass spectrometric method for simultaneous quantification of curcumin and its major metabolite: curcumin-O-glucuronide (COG), in the linear range of 2.0-2000 ng/mL in human plasma. The intra-day and inter-day accuracies of curcumin and COG in human plasma were in the range of 91.3-111.5% and 82.7-109.2% and their co-efficiency of variations were in the range of 3.5-12.7% and 3.1-11.3%, respectively. This method was capable of detecting only COG in human plasma samples from two healthy volunteers after an oral ingestion of curcumin.
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http://dx.doi.org/10.1016/j.jchromb.2012.05.026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3387345PMC
July 2012

Synthetic microRNA cassette dosing: pharmacokinetics, tissue distribution and bioactivity.

Mol Pharm 2012 Jun 23;9(6):1638-44. Epub 2012 May 23.

Division of Pharmaceutics, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210,United States.

MicroRNAs (miRs) are deregulated in cancer and leukemia. Restoring aberrantly downregulated tumor suppressor miRs or antagonizing overexpressed oncogenic miRs in malignant cells by synthetic RNA oligonucleotides represents a potentially novel therapeutic approach in cancer and leukemia. However, given the complex networking and concurrent deregulation of miRs in malignant cells, an effective approach may require concurrent targeting of multiple miRs. Cassette dosing involves simultaneous administration of a mixture of oligonucleotides from the same or different structural classes. However, information on cassette dosing pharmacokinetics, tissue distribution and bioactivity of synthetic miRs is lacking. In this study, three synthetic 2'-methoxyphosphorothioate-miRs (2'-MeOPSmiR16-1, 2'-MeOPSmiR29b and 2'-MeOPSantagomiR155) were administered iv to C57BL/6 mice as a mixture, each at 7.5 mg/kg. Analysis of concentrations of individual miR in plasma and major organ tissues (bone marrow, spleen, liver, brain, heart, kidney and lung) was performed. The mRNA and protein levels of miR's biotargets were monitored sequentially after dosing up to 24 h. Our results demonstrated that these synthetic miRs retain their different individual pharmacokinetic properties and all display three-compartmental pharmacokinetics. 2'-MeOPSmiR16-1 has the longest plasma gamma half-life of 2508 min and lowest total body clearance of 0.0054 L/min·kg, whereas 2'-MeOPSmiR29b has the shortest gamma half-life of 510.6 min and highest total body clearance of 0.042 L/min·kg. The tissue concentrations of all three 2'-MeOPS-modified miR(s)/antagomiR were measurable from 5 min to at least 24 h after dosing, indicating that these concurrently delivered oligonucleotides can reach organ tissues. Importantly, there were biological activities of the concurrently administered miRs which persisted, as shown by the downregulation of specific targets in tested tissues, albeit with variations. Brain was one of the most sensitive tissues with respect to downregulation of mRNA and protein levels of four measured biotargets (e.g., Bcl-2, Mcl-1, DNMT3a and DNMT3b) despite its relatively low miR/antagomiRs levels. We conclude that cassette dosing is applicable to 2'-MeOPS-modified synthetic miRs that are tissue-deliverable and biofunctional without any additional formulation requirement. This study supports future exploration of miR-involved combination therapies.
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http://dx.doi.org/10.1021/mp2006483DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3977775PMC
June 2012

Evaluation of a mucoadhesive fenretinide patch for local intraoral delivery: a strategy to reintroduce fenretinide for oral cancer chemoprevention.

Carcinogenesis 2012 May 15;33(5):1098-105. Epub 2012 Mar 15.

Division of Oral Maxillofacial Surgery, Pathology and Anesthesiology, College of Dentistry, The Ohio State University, 2205 Postle Hall, 305 W. 12th Avenue, Columbus, OH 43210-1241, USA.

Systemic delivery of fenretinide in oral cancer chemoprevention trials has been largely unsuccessful due to dose-limiting toxicities and subtherapeutic intraoral drug levels. Local drug delivery, however, provides site-specific therapeutically relevant levels while minimizing systemic exposure. These studies evaluated the pharmacokinetic and growth-modulatory parameters of fenretinide mucoadhesive patch application on rabbit buccal mucosa. Fenretinide and blank-control patches were placed on right/left buccal mucosa, respectively, in eight rabbits (30 min, q.d., 10 days). No clinical or histological deleterious effects occurred. LC-MS/MS analyses of post-treatment samples revealed a delivery gradient with highest fenretinide levels achieved at the patch-mucosal interface (no metabolites), pharmacologically active levels in fenretinide-treated oral mucosa (mean: 5.65 μM; trace amounts of 4-oxo-4-HPR) and undetectable sera levels. Epithelial markers for cell proliferation (Ki-67), terminal differentiation (transglutaminase 1-TGase1) and glucuronidation (UDP-glucuronosyltransferase1A1-UGT1A1) exhibited fenretinide concentration-specific relationships (elevated TGase1 and UGT1A1 levels <5 μM, reduced Ki-67 indices >5 μM) relative to blank-treated epithelium. All fenretinide-treated tissues showed significantly increased intraepithelial apoptosis (TUNEL) positivity, implying activation of intersecting apoptotic and differentiation pathways. Human oral mucosal correlative studies showed substantial interdonor variations in levels of the enzyme (cytochrome P450 3A4-CYP3A4) responsible for conversion of fenretinide to its highly active metabolite, 4-oxo-4-HPR. Complementary in vitro assays in human oral keratinocytes revealed fenretinide and 4-oxo-4-HPR's preferential suppression of DNA synthesis in dysplastic as opposed to normal oral keratinocytes. Collectively, these data showed that mucoadhesive patch-mediated fenretinide delivery is a viable strategy to reintroduce a compound known to induce keratinocyte differentiation to human oral cancer chemoprevention trials.
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http://dx.doi.org/10.1093/carcin/bgs122DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3334520PMC
May 2012

Dopamine stabilizes tumor blood vessels by up-regulating angiopoietin 1 expression in pericytes and Kruppel-like factor-2 expression in tumor endothelial cells.

Proc Natl Acad Sci U S A 2011 Dec 5;108(51):20730-5. Epub 2011 Dec 5.

Department of Pathology, Ohio State University, Columbus, OH 43210, USA.

Impaired blood flow in the tumor vascular bed caused by structurally and functionally abnormal blood vessels not only hinders the delivery of chemotherapeutic agents but also aggravates tumor hypoxia, making the tumor cells further resistant to antineoplastic drugs. Therefore, normalization of tumor blood vessels may be an important approach to increase therapeutic efficacy in the treatment of cancer patients. As blood vessels are supplied by sympathetic nerves containing dopamine (DA), and DA regulates functions of normal blood vessels through its receptors present in these vessels, we investigated the effect of DA on tumor vasculature. Here we report loss of sympathetic innervation and endogenous DA in abnormal and immature tumor blood vessels in malignant colon and prostate tumor tissues. In contrast, exogenous administration of DA normalizes the morphology and improves the functions of these vessels by acting on pericytes and endothelial cells, the two major cellular components of blood vessels. DA acts through its D(2) receptors present in these cells to up-regulate directly the expression of angiopoietin 1 (Ang1) in pericytes and the expression of the zinc finger transcriptional factor, Krüppel-like factor-2 (KLF2) in tumor endothelial cells. Importantly, this vessel stabilization by DA also significantly increases the concentration of anticancer drug in tumor tissues. These results show a relationship between vascular stabilization and a neurotransmitter and indicate that DA or its D(2) receptor-specific agonists can be an option for the treatment of cancer and disorders in which normalization of blood vessels may have therapeutic benefits.
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http://dx.doi.org/10.1073/pnas.1108696108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3251052PMC
December 2011

Enhancement of curcumin oral absorption and pharmacokinetics of curcuminoids and curcumin metabolites in mice.

Cancer Chemother Pharmacol 2012 Mar 4;69(3):679-89. Epub 2011 Oct 4.

College of Pharmacy, The Ohio State University, Room 152, Riffe Building, 500 W. 12th Avenue, Columbus, OH 43210, USA.

Purpose: Curcumin has shown a variety of biological activity for various human diseases including cancer in preclinical setting. Its poor oral bioavailability poses significant pharmacological barriers to its clinical application. Here, we established a practical nano-emulsion curcumin (NEC) containing up to 20% curcumin (w/w) and conducted the pharmacokinetics of curcuminoids and curcumin metabolites in mice.

Methods: This high loading NEC was formulated based on the high solubility of curcumin in polyethylene glycols (PEGs) and the synergistic enhancement of curcumin absorption by PEGs and Cremophor EL. The pharmacokinetics of curcuminoids and curcumin metabolites was characterized in mice using a LC-MS/MS method, and the pharmacokinetic parameters were determined using WinNonlin computer software.

Results: A tenfold increase in the AUC (0→24h) and more than 40-fold increase in the C (max) in mice were observed after an oral dose of NEC compared with suspension curcumin in 1% methylcellulose. The plasma pharmacokinetics of its two natural congeners, demethoxycurcumin and bisdemethoxycurcumin, and three metabolites, tetrahydrocurcumin (THC), curcumin-O-glucuronide, and curcumin-O-sulfate, was characterized for the first time in mice after an oral dose of NEC.

Conclusion: This oral absorption enhanced NEC may provide a practical formulation to conduct the correlative study of the PK of curcuminoids and their pharmacodynamics, e.g., hypomethylation activity in vivo.
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http://dx.doi.org/10.1007/s00280-011-1749-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3368221PMC
March 2012

Phase I trial of lenalidomide and CCI-779 in patients with relapsed multiple myeloma: evidence for lenalidomide-CCI-779 interaction via P-glycoprotein.

J Clin Oncol 2011 Sep 8;29(25):3427-34. Epub 2011 Aug 8.

The Ohio State University, Columbus, OH 43210, USA.

Purpose: Multiple myeloma (MM) is an incurable plasma-cell neoplasm for which most treatments involve a therapeutic agent combined with dexamethasone. The preclinical combination of lenalidomide with the mTOR inhibitor CCI-779 has displayed synergy in vitro and represents a novel combination in MM.

Patients And Methods: A phase I clinical trial was initiated for patients with relapsed myeloma with administration of oral lenalidomide on days 1 to 21 and CCI-779 intravenously once per week during a 28-day cycle. Pharmacokinetic data for both agents were obtained, and in vitro transport and uptake studies were conducted to evaluate potential drug-drug interactions.

Results: Twenty-one patients were treated with 15 to 25 mg lenalidomide and 15 to 20 mg CCI-779. The maximum-tolerated dose (MTD) was determined to be 25 mg lenalidomide with 15 mg CCI-779. Pharmacokinetic analysis indicated increased doses of CCI-779 resulted in statistically significant changes in clearance, maximum concentrations, and areas under the concentration-time curves, with constant doses of lenalidomide. Similar and significant changes for CCI-779 pharmacokinetics were also observed with increased lenalidomide doses. Detailed mechanistic interrogation of this pharmacokinetic interaction demonstrated that lenalidomide was an ABCB1 (P-glycoprotein [P-gp]) substrate.

Conclusion: The MTD of this combination regimen was 25 mg lenalidomide with 15 mg CCI-779, with toxicities of fatigue, neutropenia, and electrolyte wasting. Pharmacokinetic and clinical interactions between lenalidomide and CCI-779 seemed to occur, with in vitro data indicating lenalidomide was an ABCB1 (P-gp) substrate. To our knowledge, this is the first report of a clinically significant P-gp-based drug-drug interaction with lenalidomide.
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http://dx.doi.org/10.1200/JCO.2010.32.4962DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3164245PMC
September 2011

Effects of human oral mucosal tissue, saliva, and oral microflora on intraoral metabolism and bioactivation of black raspberry anthocyanins.

Cancer Prev Res (Phila) 2011 Aug 10;4(8):1209-21. Epub 2011 May 10.

Division of Oral Maxillofacial Surgery, Pathology & Anesthesiology, College of Dentistry, 2191B Postle Hall, 305 W. 12th Ave, The Ohio State University, Columbus, OH 43210, USA.

Our oral cancer chemoprevention trial data implied that patient-specific differences in local retention and metabolism of freeze-dried components of black raspberries (BRB) affected therapeutic responsiveness. Subsequent studies have confirmed that anthocyanins are key contributors to BRB's chemopreventive effects. Consequently, functional assays, immunoblotting, and immunohistochemical analyses to evaluate levels and distribution of BRB anthocyanin-relevant metabolic enzymes in human oral tissues were conducted. Liquid chromatography/tandem mass spectrometry (LC/MS-MS) analyses of time course saliva samples collected following BRB rinses were conducted to assess local pharmacokinetics and compare the capacities of three different BRB rinse formulations to provide sustained intraoral levels of anthocyanins. Protein profiles showed the presence of key metabolic enzymes in all 15 oral mucosal tissues evaluated, whereas immunohistochemistry confirmed these enzymes were distributed within surface oral epithelia and terminal salivary ducts. β-Glucosidase assays confirmed that whole and microflora-reduced saliva can deglycosylate BRB anthocyanins, enabling generation of the bioactive aglycone, cyanidin. LC/MS-MS analyses showed retention of parent anthocyanins and their functional, stable metabolite, protocatechuic acid, in saliva for up to 4 hours after rinsing. Furthermore, postrinse saliva samples contained glucuronidated anthocyanin conjugates, consistent with intracellular uptake and phase II conversion of BRB anthocyanins into forms amenable to local recycling. Our data show that comparable to the small intestine, the requisite hydrolytic, phase II and efflux transporting enzymes necessary for local enteric recycling are present and functional in human oral mucosa. Notably, interpatient differences in anthocyanin bioactivation and capacities for enteric recycling would impact treatment as retention of bioactivated chemopreventives at the target site would sustain therapeutic effectiveness.
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http://dx.doi.org/10.1158/1940-6207.CAPR-11-0040DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3151333PMC
August 2011

Characterization of silvestrol pharmacokinetics in mice using liquid chromatography-tandem mass spectrometry.

AAPS J 2011 Sep 16;13(3):347-56. Epub 2011 Apr 16.

College of Pharmacy, The Ohio State University, Columbus, 43210, USA.

A sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of the plant natural product silvestrol in mice, using ansamitocin P-3 as the internal standard. The method was validated in plasma with a lower limit of quantification of 1 ng/mL, accuracy ranging from 87 to 114%, and precision (coefficient of variation) below 15%. The validated method was used to characterize pharmacokinetics in C57BL/6 mice and metabolism in mouse, human and rat plasma, and liver microsomes. Mice were dosed with silvestrol formulated in hydroxypropyl-β-cyclodextrin via intravenous, intraperitoneal, and oral routes followed by blood sampling up to 24 h. Intraperitoneal systemic availability was 100%, but oral administration resulted in only 1.7% bioavailability. Gradual degradation of silvestrol was observed in mouse and human plasma, with approximately 60% of the parent drug remaining after 6 h. In rat plasma, however, silvestrol was completely converted to silvestric acid (SA) within 10 min. Evaluation in microsomes provided further evidence that the main metabolite formed was SA, which subsequently showed no cytotoxic or cytostatic activity in a silvestrol-sensitive lymphoblastic cell line. The ability of the analytical assay to measure tissue levels of silvestrol was evaluated in liver, brain, kidney, and spleen. Results indicated the method was capable of accurately measuring tissue levels of silvestrol and suggested it has a relatively low distribution to brain. Together, these data suggest an overall favorable pharmacokinetic profile of silvestrol in mice and provide crucial information for its continued development toward potential clinical testing.
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http://dx.doi.org/10.1208/s12248-011-9273-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3160157PMC
September 2011

A liquid chromatography-tandem mass spectrometric method for quantification of curcuminoids in cell medium and mouse plasma.

J Chromatogr B Analyt Technol Biomed Life Sci 2010 Nov 17;878(30):3045-51. Epub 2010 Sep 17.

College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA.

Curcumin and tetrahydrocurcumin (THC) have been found as potent DNMT1 inhibitors, but they suffer from low oral bioavailability and rapid metabolism in vivo. To circumvent these problems, two curcumin analogs: 1,7-bis(3,4-dimethoxyphenyl)-4,4-dimethyl-1,6-heptadiene-3,5-dione (TMC) and 1,7-bis(3,4-dimethoxyphenyl)-4-cyclohexyl-1,6-heptadiene-3,5-dione (DMCHC) have been synthesized to enhance their stability by blocking the two metabolic sites, the phenolic and C4 methylene moieties. Both compounds have shown inhibitory activity on M. SssI similar to that of curcumin and THC (Poster, M1114, AAPS, 2009). Preclinical pharmacokinetics has yet to be performed. In this paper, a simple liquid chromatography-tandem mass spectrometric method was developed for the determination of these four curcuminoids in cell medium and mouse plasma. The method showed linearity from 1 to 1000 ng/mL with the lower limit of quantification of 1 ng/mL in cell medium, and 5 ng/mL in mouse plasma for all test curcuminoids. The within-day coefficients of variation were found to be below 15% and the accuracy was in the range of 85-115%. This method was subsequently used to evaluate their stability in these matrices and a pilot pharmacokinetics of curcumin, DMCHC and TMC in mice after an intraperitoneal (i.p.) cassette dosing of 10mg/kg each. Curcuminoids degraded in two phases with terminal half lives of 186, 813, 724, and 2000 min for curcumin, THC, TMC, and DMCHC, respectively, in cell culture medium. In plasma, their respective half lives were 111, 232, 1202 and 3000 min. These data demonstrated that their stability is in the order curcumin
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http://dx.doi.org/10.1016/j.jchromb.2010.08.039DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2975763PMC
November 2010

A novel ultrasensitive hybridization-based ELISA method for 2-methoxyphosphorothiolate microRNAs and its in vitro and in vivo application.

AAPS J 2010 Dec 13;12(4):556-68. Epub 2010 Jul 13.

The Ohio State University, Columbus, 43210, USA.

MicroRNAs (miRNAs) are endogenous, small non-coding RNAs that bind to target mRNAs and regulate their expression. Recent evidence has indicated the involvement of miRNAs in human malignancies. It has been suggested that aberrantly down-regulated or up-regulated miRNAs may be replaced with synthetic miRNAs or antagomiRNAs, respectively, and restore normal cell functions. As therapeutic development requires analytical support, we developed and validated an ultrasensitive and selective assay for quantification of synthetic 2'-methoxyphosphorothiolate-miRNA in mouse plasma and cell lysate for the first time. The method is based on a hybridization-ligation fluorescence enzyme-linked immunosorbent assay and has provided a linear dynamic range of 10-1,000,000 pM for three synthetic miRNAs both singly and in a mixture. The intra- and inter-day coefficients of variation were <20% and the accuracy values nearly 100%. Using this assay, we performed pharmacokinetic studies of three synthetic miRNAs in mice treated with a single i.v. bolus dose of 7.5 mg kg⁻¹. The 2-methoxyphosphorothiolate-miRNAs reached peak concentrations in the μM and nM ranges in plasma and bone marrow, respectively, and remained measurable at 24 h. These concentrations are in a range that shows biological activities. We conclude that this method provides a general and valuable tool for the pharmacologic study and clinical development of synthetic miRNAs.
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http://dx.doi.org/10.1208/s12248-010-9214-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2976995PMC
December 2010

Phase I trial of low dose decitabine targeting DNA hypermethylation in patients with chronic lymphocytic leukaemia and non-Hodgkin lymphoma: dose-limiting myelosuppression without evidence of DNA hypomethylation.

Br J Haematol 2010 Jul 29;150(2):189-95. Epub 2010 Apr 29.

Division of Hematology-Oncology, Department of Internal Medicine, The Arthur G. James Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA.

Targeting aberrant DNA hypermethylation in chronic lymphocytic leukaemia (CLL) and non-Hodgkin lymphoma (NHL) with decitabine may reverse epigenetic silencing in B-cell malignancies. Twenty patients were enrolled in two phase I trials to determine the minimum effective pharmacological dose of decitabine in patients with relapsed/refractory CLL (n = 16) and NHL (n = 4). Patients received 1-3 cycles of decitabine. Dose-limiting toxicity (DLT) was observed in 2 of 4 CLL and 2 of 2 NHL patients receiving decitabine at 15 mg/m(2) per d days 1-10, consisting of grade 3-4 thrombocytopenia and hyperbilirubinaemia. Six patients with CLL received decitabine at 10 mg/m(2) per d days 1-10 without DLT; however, re-expression of methylated genes or changes in global DNA methylation were not observed. Therefore, a 5-day decitabine schedule was examined. With 15 mg/m(2) per d decitabine days 1-5, DLT occurred in 2 of 6 CLL and 2 of 2 NHL patients, consisting of grade 3-4 neutropenia, thrombocytopenia, and febrile neutropenia. Eight patients had stable disease. In 17 patients, there were no significant changes in genome-wide methylation or in target gene re-expression. In conclusion, dose-limiting myelosuppression and infectious complications prevented dose escalation of decitabine to levels associated with changes in global methylation or gene re-expression in CLL and NHL.
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http://dx.doi.org/10.1111/j.1365-2141.2010.08213.xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2917115PMC
July 2010

A rapid and sensitive LC-MS/MS method for quantification of four anthocyanins and its application in a clinical pharmacology study of a bioadhesive black raspberry gel.

J Chromatogr B Analyt Technol Biomed Life Sci 2009 Dec 30;877(31):4027-34. Epub 2009 Oct 30.

College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA.

Cyanidin 3-glucoside (C3GLU), cyanidin 3-rutinoside (C3RUT), cyanidin 3-sambubioside (C3SAM) and cyanidin 3-(2(G)-xylosyl) rutinoside (C3XRUT) are the four constituent black raspberry anthocyanins that contribute significantly to the chemopreventive effects of freeze-dried black raspberries (FBR). A highly sensitive and specific LC-MS/MS assay was developed and validated to simultaneously quantify these four FBR anthocyanins in human saliva, plasma and oral tissue homogenates. In saliva, the lower limit of quantification (LLOQ) for these anthocyanins was 1.0 ng/mL. The within-run and between-run coefficients of variations (CVs) at the quality control concentrations (1.0, 5.0, 50 and 500 ng/mL) were all <12%, except for C3SAM and C3RUT at the LLOQ, which showed a within-run CV of 18.3% and between-run CV of 16.0%, respectively. The accuracy values ranged from 87.5 to 110%. In plasma, the LLOQ for C3GLU and C3RUT was 1.0 ng/mL and for C3SAM 5.0 ng/mL. The CVs at the above concentrations were <15%, except for C3GLU at the LLOQ, which showed the between-run CV of 16.9%. The accuracy values ranged from 90.7% to 112.7% except for C3GLU at the LLOQ, which showed 119.3%. In tissue homogenates, the LLOQ for C3GLU and C3RUT was 2.0 ng/mL, and C3SAM 5.0 ng/mL. The CVs and accuracy values at concentrations (2.0, 5.0, 50 and 500 ng/mL) were similar to those in human plasma. This assay was subsequently used in a pilot pharmacology study to evaluate the effects of topical application of a 10% (w/w) FBR bioadhesive gel to selected mucosal sites in the posterior mandibular gingiva. Measurable saliva and tissue levels of the FBR anthocyanins confirmed that gel-delivered anthocyanins are readily distributed to saliva and easily penetrate human oral mucosa.
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http://dx.doi.org/10.1016/j.jchromb.2009.10.026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2796431PMC
December 2009