Publications by authors named "Taeho Lee"

131 Publications

Nontargeted Metabolomics by High-Resolution Mass Spectrometry to Study the In Vitro Metabolism of a Dual Inverse Agonist of Estrogen-Related Receptors β and γ, DN203368.

Pharmaceutics 2021 May 31;13(6). Epub 2021 May 31.

BK21 FOUR KNU Community-Based Intelligent Novel Drug Discovery Education Unit, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Korea.

DN203368 (()-3-[1-(4-[4-isopropylpiperazine-1-yl]phenyl) 3-methyl-2-phenylbut-1-en-1-yl] phenol) is a 4-hydroxy tamoxifen analog that is a dual inverse agonist of estrogen-related receptor β/γ (ERRβ/γ). ERRγ is an orphan nuclear receptor that plays an important role in development and homeostasis and holds potential as a novel therapeutic target in metabolic diseases such as diabetes mellitus, obesity, and cancer. ERRβ is also one of the orphan nuclear receptors critical for many biological processes, such as development. We investigated the in vitro metabolism of DN203368 by conventional and metabolomic approaches using high-resolution mass spectrometry. The compound (100 μM) was incubated with rat and human liver microsomes in the presence of NADPH. In the metabolomic approach, the value and retention time information obtained from the sample and heat-inactivated control group were statistically evaluated using principal component analysis and orthogonal partial least-squares discriminant analysis. Significant features responsible for group separation were then identified using tandem mass spectra. Seven metabolites of DN203368 were identified in rat liver microsomes and the metabolic pathways include hydroxylation (M1-3), -oxidation (M4), -deisopropylation (M5), -dealkylation (M6), and oxidation and dehydrogenation (M7). Only five metabolites (M2, M3, and M5-M7) were detected in human liver microsomes. In the conventional approach using extracted ion monitoring for values of mass increase or decrease by known metabolic reactions, only five metabolites (M1-M5) were found in rat liver microsomes, whereas three metabolites (M2, M3, and M5) were found in human liver microsomes. This study revealed that nontargeted metabolomics combined with high-resolution mass spectrometry and multivariate analysis could be a more efficient tool for drug metabolite identification than the conventional approach. These results might also be useful for understanding the pharmacokinetics and metabolism of DN203368 in animals and humans.
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http://dx.doi.org/10.3390/pharmaceutics13060776DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8230175PMC
May 2021

Weak Measurement of a Superconducting Qubit Reconciles Incompatible Operators.

Phys Rev Lett 2021 Mar;126(10):100403

Department of Physics, Washington University, St. Louis, Missouri 63130, USA.

Traditional uncertainty relations dictate a minimal amount of noise in incompatible projective quantum measurements. However, not all measurements are projective. Weak measurements are minimally invasive methods for obtaining partial state information without projection. Recently, weak measurements were shown to obey an uncertainty relation cast in terms of entropies. We experimentally test this entropic uncertainty relation with strong and weak measurements of a superconducting transmon qubit. A weak measurement, we find, can reconcile two strong measurements' incompatibility, via backaction on the state. Mathematically, a weak value-a preselected and postselected expectation value-lowers the uncertainty bound. Hence we provide experimental support for the physical interpretation of the weak value as a determinant of a weak measurement's ability to reconcile incompatible operations.
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http://dx.doi.org/10.1103/PhysRevLett.126.100403DOI Listing
March 2021

Catalytic Gasification of Rice Hull Using Municipal Solid Waste Incineration Bottom Ash.

J Nanosci Nanotechnol 2021 07;21(7):3764-3768

Department of Environmental Engineering, Daegu University, Gyeongsan, 38453, Republic of Korea.

The demand for alternative energy is increasing rapidly because of global warming and the depletion of fossil fuels. Gasification is a technology that produces gaseous fuels through the incomplete combustion of waste or biomass. The introduction of a catalyst during gasification may increase the production of H₂ and reduce tar formation. In this study, the catalytic gasification of rice hulls was carried out using a fluidized gasifier. To improve the gas yield and reduce tar, municipal solid waste incineration bottom ash (IBA) having nanoporosity was introduced as a substitute for the fluidized bed material. Gasification was carried out at 800 °C, and the flow materials were silica sand, dolomite, and incineration bottom ash. The equivalence ratio, which is the ratio of oxygen supplied to oxygen required for complete combustion, was set to 0.3. The application of alternate fluidized bed materials (dolomite and incineration bottom ash) was effective in improving the hydrogen yield and tar reduction. This was attributed to the high Ca and Mg contents in dolomite and incineration bottom ash. Therefore, it is expected that IBA can be utilized as a catalytic fluidized bed material to replace silica sand.
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http://dx.doi.org/10.1166/jnn.2021.19195DOI Listing
July 2021

Alkyl-Side-Chain Engineering of Nonfused Nonfullerene Acceptors with Simultaneously Improved Material Solubility and Device Performance for Organic Solar Cells.

ACS Omega 2021 Feb 9;6(7):4562-4573. Epub 2021 Feb 9.

Department of Applied Chemistry, University of Seoul, 163 Seoulsiripdae-ro, Dongdaemun-gu, Seoul 02504, Republic of Korea.

Two nonfullerene small molecules, and , which have the same thiophene-benzothiadiazole-thiophene (TBTT) core flanked with butyloctyl (BO)- and octyl (O)-substituted rhodanines (RHs) at both ends, respectively, are developed as electron acceptors for organic solar cells (OSCs). The difference between the alkyl groups introduced into and strongly influence the intermolecular aggregation in the film state. Differential scanning calorimetry and UV-vis absorption studies reveal that exhibited stronger molecular aggregation behavior than . On the contrary, the material solubility is greatly improved by the introduction of a BO group in , and the inevitably low molecular interaction and packing ability of the as-cast film can be effectively increased by a solvent-vapor annealing (SVA) treatment. OSCs based on the two acceptors and PTB7-Th as a polymer donor are fabricated owing to their complementary absorption and sufficient energy-level offsets. The best power conversion efficiency of 8.33% is obtained with the SVA-treated device, where, together with a high open-circuit voltage of 1.02 V, the charge-carrier mobility and the short-circuit current density were greatly improved by the SVA treatment to levels comparable to those of the device because of the suppressed charge recombination and improved film morphology. In this work, the simultaneous improvement of both material solubility and device performance is achieved through alkyl side-chain engineering to balance the trade-offs among material solubility/crystallinity/device performance.
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http://dx.doi.org/10.1021/acsomega.0c04495DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7905825PMC
February 2021

Selective inhibitory effects of HYIpro-3-1 on CYP1A2 in human liver microsomes.

Biopharm Drug Dispos 2021 Jan;42(1):35-41

BK21 FOUR Community-Based Intelligent Novel Drug Discovery Education Unit, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, Republic of Korea.

CYP1A2 is one of the main Cytochrome P450 enzymes in the human liver associated with the metabolism of several xenobiotics. CYP1A2 is especially involved in the metabolic activation of different procarcinogens. Therefore, the development of cancer may be inhibited by inhibiting CYP1A2 activity. Here, the inhibitory effect of HYIpro-3-1 and its derivatives on CYP1A2 activity in human liver microsomes (HLM) was studied through LC-MS/MS using a cocktail assay. Among the four compounds, HYIpro-3-1 showed the most selective and strongest inhibitory effect on CYP1A2 at IC values of 0.1 µM in HLMs and inhibition was confirmed using purified human CYP1A2. It was determined that inhibition is reversible because the inhibitory effect of HYIpro-3-1 is not dependent on preincubation time. HYIpro-3-1 showed a typical pattern of competitive inhibition for CYP1A2-catalyzed phenacetin O-deethylation, based on the Lineweaver-Burk plot, with a Ki value of 0.05 μM in HLMs; the secondary plot also showed a linear pattern. In our study, HYIpro-3-1 was proposed as a novel inhibitor with the capacity to selectively inhibit CYP1A activity in HLMs.
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http://dx.doi.org/10.1002/bdd.2259DOI Listing
January 2021

Understanding complete ammonium removal mechanism in single-chamber microbial fuel cells based on microbial ecology.

Sci Total Environ 2021 Apr 24;764:144231. Epub 2020 Dec 24.

Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea. Electronic address:

The removal of organics and ammonium from domestic wastewater was successfully achieved by a flat-panel air-cathode microbial fuel cell (FA-MFC). To elucidate the reason for complete ammonium removal in the single-chamber MFCs, microbial communities were analyzed in biofilms on the surface of each anode, separator, and cathode of separator-electrode assemblies (SEAs). The spatial distribution of bacterial families related to the nitrogen cycle varied based on local conditions. Since oxygen diffusing from the air-cathode created a locally aerobic condition, ammonia-oxidizing bacteria (AOB) Nitrosomonadacea and nitrite-oxidizing bacteria (NOB) Nitrospiraceae were present near the cathode. NOB (~12.1%) was more abundant than AOB (~4.4%), suggesting that the nitrate produced by NOB may be reduced back to nitrite by heterotrophic denitrifiers such as Rhodocyclaceae (~21.7%) and Comamonadaceae (~5%) in the anoxic zone close to the NOB layer. Near that zone, the "nitrite loop" also substantially enriched two nitrite-reducing bacterial families: Ignavibacteriaceae (~18.1%), facultative heterotrophs, and Brocadiaceae (~11.2%), anaerobic ammonium oxidizing autotrophs. A larger inner area of biofilm contained abundant heterotrophic denitrifiers and fermentation bacteria. These results indicate that the large-surface SEA of FA-MFC allows counter-diffusion between substrates and oxygen, resulting in interactions of bacteria involved in the nitrogen cycle for complete ammonium removal.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144231DOI Listing
April 2021

Nitrogen removal and microbial community diversity in single-chamber electroactive biofilm reactors with different ratios of the cathode surface area to reactor volume.

Sci Total Environ 2021 Mar 27;758:143677. Epub 2020 Nov 27.

Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea. Electronic address:

Removal of nitrogen compounds is particularly important domestic wastewater treatment. Our recent study reported the successful removal of nitrogen in single-chamber electroactive biofilm reactors (EBRs) under aeration-free conditions. We hypothesized that the oxygen diffused from the air-cathode is a key factor in the removal of nitrogen in the EBR. If so, the effect of the penetrated oxygen would vary according to the ratio of the air-cathode surface area to the reactor volume (AV ratio) and the hydraulic retention time (HRT). In this study, single-chamber EBRs with three different AV ratios: 125 m/m (EBR-125), 250 m/m (EBR-250), and 500 m/m (EBR-500) were evaluated for the removal of nitrogen under different HRTs of 0.5-6 h. The higher the AV ratio, the greater the increase in nitrification. The total nitrogen (TN) removal efficiency of EBR-125 and EBR-250 decreased as the HRT decreased, while that of EBR-500 increased. EBR-250 showed the highest TN removal (62.0%) with well-balanced nitrification (83.9%) and denitrification (75.1%) at an HRT of 6 h. However, EBR-500 appeared to be superior for practical application because it showed a comparable TN removal (59%) at a substantially short HRT of 1 h. The microbial communities that were involved in the nitrogen cycle varied according to whether the biofilms were located on the anodes, separators, and cathodes but were similar among EBRs with different AV ratios. Nitrifying bacteria were detected in the biofilms that were presented on the cathodes (approximately 7.8% of the total phylotypes), while denitrifying bacteria were mainly found in biofilm that were located on the anodes (approximately 23.3%). Anammox bacteria were also detected on the anode (approximately 3.7%) and in the separator biofilms (approximately 1.9%) of all the EBRs. These results suggest that both the A/V ratio and the HRT could affect the counter diffusion of substrates (NH and organic compounds) and oxygen in the biofilms and allow interactions between a diversity of microorganisms for the successful removal of nitrogen in EBRs. These findings are expected to aid in the development of new applications using EBR for energy-saving wastewater treatment.
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http://dx.doi.org/10.1016/j.scitotenv.2020.143677DOI Listing
March 2021

Inhibitory functions of cardamonin against particulate matter-induced lung injury through TLR2,4-mTOR-autophagy pathways.

Fitoterapia 2020 Oct 15;146:104724. Epub 2020 Sep 15.

College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics based Creative Drug Research Team, Kyungpook National University, Daegu 41566, Republic of Korea. Electronic address:

Particulate matter with an aerodynamic diameter equal to or less than 2.5 μm (PM) is a form of air pollutant that causes significant lung damage when inhaled. Cardamonin, a flavone found in Alpinia katsumadai Heyata seeds, has been reported to have anti-inflammatory and anticoagulative activity. The aim of this study was to determine the protective effects of cardamonin on PM-induced lung injury. Mice were treated with cardamonin via tail-vein injection 30 min after the intratracheal instillation of PM. The results showed that cardamonin markedly reduced the pathological lung injury, lung wet/dry weight ratio, and hyperpermeability caused by PM. Cardamonin also significantly inhibited PM-induced myeloperoxidase (MPO) activity in lung tissue, decreased the levels of PM-induced inflammatory cytokines and effectively attenuated PM-induced increases in the number of lymphocytes in the bronchoalveolar lavage fluid (BALF). And, cardamonin increased the phosphorylation of mammalian target of rapamycin (mTOR) and dramatically suppressed the PM-stimulated expression of toll-like receptor 2 and 4 (TLR 2,4), MyD88, and the autophagy-related proteins LC3 II and Beclin 1. In conclusion, these findings indicate that cardamonin has a critical anti-inflammatory effect due to its ability to regulate both the TLR2,4-MyD88 and mTOR-autophagy pathways and may thus be a potential therapeutic agent against PM-induced lung injury.
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http://dx.doi.org/10.1016/j.fitote.2020.104724DOI Listing
October 2020

Identification of suberosin metabolites in human liver microsomes by high-performance liquid chromatography combined with high-resolution quadrupole-orbitrap mass spectrometer.

J Mass Spectrom 2021 Apr 30;56(4):e4623. Epub 2020 Jul 30.

BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, 41566, Republic of Korea.

Suberosin is a natural prenylated coumarin derivative isolated from Citropsis articulata. It has various pharmacological properties, especially as an anticoagulant, for which it has been used since antiquity. However, its metabolic pathway and metabolites have not yet been studied. Therefore, this study characterizes its metabolic pathway and metabolites in human liver microsomes (HLMs) using high-resolution quadrupole-orbitrap mass spectrometry (HRMS/MS). Eight metabolites (M1-M8) were found, including three monohydroxylated (M1-M3), one hydrated (M4), three dihydroxylated (M5-M7), and one glucuronide conjugate (M8). Furthermore, forms of cytochrome P450 (CYPs) responsible for suberosin metabolism in HLMs were characterized. CYP1A2 was identified as a major enzyme for the production of M1 and M5 metabolites. The M2, M3, and M7 metabolites were predominantly generated by CYP2B6. M8 was the only phase II metabolite, identified as a glucuronide conjugate from either M1 or M2. This glucuronide conjugate may be the only promising metabolite from phase II metabolism. Phase I metabolism, especially hydroxylation, was found to provide a predominant metabolic pathway of suberosin in HLMs. Further studies should be conducted to explore the metabolites, examining their efficacy and their toxicity in an in vivo system.
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http://dx.doi.org/10.1002/jms.4623DOI Listing
April 2021

Characterization of hydrocoptisonine metabolites in human liver microsomes using a high-resolution quadrupole-orbitrap mass spectrometer.

Xenobiotica 2020 Dec 20;50(12):1423-1433. Epub 2020 Jul 20.

BK21 Plus KNU Multi-Omics-based Creative Drug Research Team, College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, Republic of Korea.

Hydrocoptisonine is a new compound that has been isolated from the rhizomes of , which belongs to the Ranunculaceae family of Chinese medicines. Although studies on have been reported, the metabolic pathway of hydrocoptisonine in human liver microsomes (HLMs) remains unelucidated. We identified 13 metabolites in HLMs, including six Phase I metabolites and seven glucuronide conjugates, using a high-resolution quadrupole-orbitrap mass spectrometer. The major metabolic pathway was the -demethylation and mono-hydroxylation of hydrocoptisonine in HLMs. Notably, M3 metabolite was -demethylated in dioxolane structures (cyclohexa-3,5-diene-1,2-dione), which was mediated by cytochrome P450 1A2. The locations of hydroxylation and hydroxyl-glucuronidation were identified by analyzing the signature fragments generated as a result of tandem mass spectrometry, indicating hydroxylation at an aliphatic chain or aromatic ring. We determined whether the hydroxylation and glucuronidation occurred in an aromatic moiety (M5 and M12) or an aliphatic moiety (M6 and M13), respectively, based on signature fragments of the metabolites.
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http://dx.doi.org/10.1080/00498254.2020.1795304DOI Listing
December 2020

A novel sphingosylphosphorylcholine and sphingosine-1-phosphate receptor 1 antagonist, KRO-105714, for alleviating atopic dermatitis.

J Inflamm (Lond) 2020 29;17:20. Epub 2020 May 29.

Drug Discovery Platform Research Center, Therapeutics & Biotechnology Division, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong, Daejeon, 34114 Republic of Korea.

Background: Atopic dermatitis (eczema) is a type of inflammation of the skin, which presents with itchy, red, swollen, and cracked skin. The high global incidence of atopic dermatitis makes it one of the major skin diseases threatening public health. Sphingosylphosphorylcholine (SPC) and sphingosine-1-phosphate (S1P) act as pro-inflammatory mediators, as an angiogenesis factor and a mitogen in skin fibroblasts, respectively, both of which are important biological responses to atopic dermatitis. The SPC level is known to be elevated in atopic dermatitis, resulting from abnormal expression of sphingomyelin (SM) deacylase, accompanied by a deficiency in ceramide. Also, S1P and its receptor, sphingosine-1-phosphate receptor 1 (S1P1) are important targets in treating atopic dermatitis.

Results: In this study, we found a novel antagonist of SPC and S1P1, KRO-105714, by screening 10,000 compounds. To screen the compounds, we used an SPC-induced cell proliferation assay based on a high-throughput screening (HTS) system and a human S1P1 protein-based [S]-GTPγS binding assay. In addition, we confirmed the inhibitory effects of KRO-105714 on atopic dermatitis through related cell-based assays, including a tube formation assay, a cell migration assay, and an ELISA assay on inflammatory cytokines. Finally, we confirmed that KRO-105714 alleviates atopic dermatitis symptoms in a series of mouse models.

Conclusions: Taken together, our data suggest that SPC and S1P1 antagonist KRO-105714 has the potential to alleviate atopic dermatitis.
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http://dx.doi.org/10.1186/s12950-020-00244-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7257206PMC
May 2020

Verification of the Necessity of the Tolyl Group of PF-543 for Sphingosine Kinase 1 Inhibitory Activity.

Molecules 2020 May 27;25(11). Epub 2020 May 27.

College of Pharmacy, Mokpo National University, Jeonnam 58554, Korea.

PF-543, the most potent sphingosine kinase (SK) inhibitor, does not demonstrate effective anticancer activity in some cancer cells, unlike other known SK1 inhibitors. PF-543 has a non-lipid structure with a unique toluene backbone; however, the importance of this structure remains unclear. Therefore, the purpose of this study was to investigate changes in SK inhibitory and anticancer activities and to explore the role of the tolyl group structure of PF-543 through various modifications. We transformed the methyl group of PF-543 into hydrogen, fluorine, and hydroxy. PF-543 derivatives in which the methyl group was substituted by hydrogen and fluorine (compound ) demonstrated SK1 inhibitory and anticancer activities similar to PF-543. Moreover, we performed molecular modeling studies of PF-543 and compound . To assess the metabolic stability of PF-543 and compound , we determined their degree of degradation using the liver microsomes of four different animal species (human, dog, rat, and mouse). However, both PF-543 and compound showed poor microsomal stability. Therefore, for the medical applications of PF-543, the structural modifications of its other parts may be necessary. Our results provide important information for the design of additional PF-543 analogs.
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http://dx.doi.org/10.3390/molecules25112484DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7321251PMC
May 2020

Inhibitory functions of maslinic acid, a natural triterpene, on HMGB1-mediated septic responses.

Phytomedicine 2020 Apr 4;69:153200. Epub 2020 Mar 4.

College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics based Creative Drug Research Team, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea. Electronic address:

Background: Maslinic acid (MA), a natural triterpenoid from Olea europaea, prevents oxidative stress and pro-inflammatory cytokine generation. High mobility group box 1 (HMGB1) has been recognized as a late mediator of sepsis, and the inhibition of the release of HMGB1 and the recovery of vascular barrier integrity have emerged as attractive therapeutic strategies for the management of sepsis.

Methods: We tested the hypothesis that MA induces sirtuin 1 and heme oxygenase-1, which inhibit the release of HMGB1 in lipopolysaccharide (LPS)-stimulated cells, thus inhibiting HMGB1-induced hyperpermeability and increasing the survival of septic mice. MA was administered after LPS or HMGB1 challenge, and the antiseptic activity of MA was determined based on permeability, the activation of pro-inflammatory proteins, and the production of markers for tissue injury in HMGB1-activated human umbilical vein endothelial cells (HUVECs) and a cecal ligation and puncture (CLP)-induced sepsis mouse model.

Results: MA significantly reduced the release of HMGB1 in LPS-activated HUVECs and attenuated the CLP-induced release of HMGB1. Additionally, MA alleviated HMGB1-mediated vascular disruption and inhibited hyperpermeability in mice, and in vivo analysis revealed that MA reduced sepsis-related mortality and tissue injury.

Conclusion: Taken together, the present results suggest that MA reduced HMGB1 release and septic mortality and thus may be useful in the treatment of sepsis.
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http://dx.doi.org/10.1016/j.phymed.2020.153200DOI Listing
April 2020

Characterization of osthenol metabolism and its pharmacokinetics.

Xenobiotica 2020 Jul 27;50(7):839-846. Epub 2019 Dec 27.

BK21 Plus KNU Multi-Omics-based Creative Drug Research Team, College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, Republic of Korea.

Osthenol, a prenylated coumarin, is a C8-prenylated derivative of umbelliferone isolated from the root of and , an intermediate and is known as a major metabolite of desmethyl-osthole.The various pharmacological effects of osthenol have been reported. In previous studies, we investigated five hydroxylated metabolites by cytochromes P450 (CYP) and glucuronide conjugates of osthenol by uridine diphosphate-glucuronosyltransferases (UGTs). However, osthenol have very few studies have been reported on its pharmacokinetic (PK) profiling, we reported the PK parameters in mouse of osthenol through this study.After oral (5 and 20 mg/kg) and intravenous (5 mg/kg) administration, the concentration of osthenol in plasma was determined by LC-MS/MS. The quantitative method was validated in terms of linearity, accuracy, and precision. When 5 and 20 mg/kg of osthenol were orally administered, the bioavailability (BA) was found to be very low at 0.43 and 0.02%, respectively.In fact, osthenol was mostly metabolized to a two-Phase II conjugates, a sulfonyl and glucuronyl-osthenol, in the blood, which was determined by LC-HR/MS analysis of the blood sample. Because osthenol is rapidly metabolized to two conjugates by first-pass effect the BA of osthenol is low after oral administration.
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http://dx.doi.org/10.1080/00498254.2019.1705427DOI Listing
July 2020

Synthesis and Biological Evaluation of BODIPY-PF-543.

Molecules 2019 Dec 2;24(23). Epub 2019 Dec 2.

College of Pharmacy, Mokpo National University, Jeonnam 58554, Korea.

Sphingosine-1-phosphate (S1P) regulates the proliferation of various cells and promotes the growth of cancer cells. Sphingosine kinase (SK), which transforms sphingosine into S1P, has two isotypes: SK1 and SK2. To date, both isotypes are known to be involved in the proliferation of cancer cells. PF-543, an SK1 inhibitor developed by Pfizer, strongly inhibits SK1. However, despite its strong SK1 inhibitory effect, PF-543 shows low anticancer activity in vitro. Therefore, additional biological evidence on the anticancer activity of SK1 inhibitor is required. The present study aimed to investigate the intracellular localization of PF-543 and identify its association with anticancer activity by introducing a fluoroprobe into PF-543. Boron-dipyrromethene (BODIPY)-introduced PF-543 has a similar SK1 inhibitory effect as PF-543. These results indicate that the introduction of BODIPY does not significantly affect the inhibitory effect of SK1. In confocal microscopy after BODIPY-PF-543 treatment, the compound was mainly located in the cytosol of the cells. This study demonstrated the possibility of introducing fluorescent material into an SK inhibitor and designing a synthesized compound that is permeable to cells while maintaining the SK inhibitory effect.
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http://dx.doi.org/10.3390/molecules24234408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6930633PMC
December 2019

Assessing Drug Interaction and Pharmacokinetics of Loxoprofen in Mice Treated with CYP3A Modulators.

Pharmaceutics 2019 Sep 16;11(9). Epub 2019 Sep 16.

BK21 Plus KNU Multi-Omics based Creative Drug Research Team, College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Korea.

Loxoprofen (LOX) is a non-selective cyclooxygenase inhibitor that is widely used for the treatment of pain and inflammation caused by chronic and transitory conditions. Its alcoholic metabolites are formed by carbonyl reductase (CR) and they consist of trans-LOX, which is active, and cis-LOX, which is inactive. In addition, LOX can also be converted into an inactive hydroxylated metabolite (OH-LOXs) by cytochrome P450 (CYP). In a previous study, we reported that CYP3A4 is primarily responsible for the formation of OH-LOX in human liver microsomes. Although metabolism by CYP3A4 does not produce active metabolites, it can affect the conversion of LOX into trans-/cis-LOX, since CYP3A4 activity modulates the substrate LOX concentration. Although the pharmacokinetics (PK) and metabolism of LOX have been well defined, its CYP-related interactions have not been fully characterized. Therefore, we investigated the metabolism of LOX after pretreatment with dexamethasone (DEX) and ketoconazole (KTC), which induce and inhibit the activities of CYP3A, respectively. We monitored their effects on the PK parameters of LOX, cis-LOX, and trans-LOX in mice, and demonstrated that their PK parameters significantly changed in the presence of DEX or KTC pretreatment. Specifically, DEX significantly decreased the concentration of the LOX active metabolite formed by CR, which corresponded to an increased concentration of OH-LOX formed by CYP3A4. The opposite result occurred with KTC (a CYP3A inhibitor) pretreatment. Thus, we conclude that concomitant use of LOX with CYP3A modulators may lead to drug-drug interactions and result in minor to severe toxicity even though there is no direct change in the metabolic pathway that forms the LOX active metabolite.
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http://dx.doi.org/10.3390/pharmaceutics11090479DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6781309PMC
September 2019

Stimulatory Effects of KPR-A148 on Osteoblast Differentiation and Bone Regeneration.

Tissue Eng Regen Med 2019 08 17;16(4):405-413. Epub 2019 Jul 17.

1Department of Oral Pathology and Regenerative Medicine, School of Dentistry, Institute for Hard Tissue and Bio-tooth Regeneration (IHBR), Kyungpook National University, 2177 Dalgubeol-daero, Jung-gu, Daegu, 41940 Republic of Korea.

Background: Xanthine derivatives have been used to treat a variety of medical conditions including respiratory disease and neural degeneration. However, few studies have reported their effects on bone regeneration. Therefore, we investigated the effects of KPR-A148, a synthetic xanthine derivative on osteoblast differentiation and bone regeneration .

Methods: The cytotoxicity of KPR-A148 was evaluated using MC3T3-E1 cells by the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltertrazolium bromide assay. The effects of KPR-A148 on osteoblast differentiation were examined by alkaline phosphatase staining, Alizarin red S staining, and real-time PCR of osteoblast differentiation marker genes. To investigate the effects of KPR-A148 on bone regeneration, a KPR-A148-containing collagen sponge was implanted into a mouse calvarial defect and KPR-A148 was injected twice, weekly. Bone regeneration was evaluated quantitatively by micro-CT and qualitatively by hematoxylin and eosin, as well as Masson's Trichrome staining.

Results: KPR-A148 did not show toxicity in the MC3T3-E1 cells and promoted osteoblast differentiation in a concentration-dependent manner. 10 μM of KPR-A148 showed the most significant effect on alkaline phospatase staining and matrix mineralization. KPR-A148 increased the expression of osteoblast marker genes in both the early and late stages of differentiation. In addition, KPR-A148 significantly induced new bone formation in the calvarial defect model.

Conclusion: These results demonstrate that KPR-A148 strongly induces osteoblast differentiation and new bone formation. Therefore, it could be used as a potential therapeutic agent for regenerating bone following its destruction by disease or trauma.
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http://dx.doi.org/10.1007/s13770-019-00200-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6675851PMC
August 2019

Identification of sulfonyl-loxoprofen as novel phase 2 conjugate in rat.

Biopharm Drug Dispos 2019 Jul 19;40(7):234-241. Epub 2019 Jul 19.

BK21 Plus KNU Multi-Omics based Creative Drug Research Team, College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, 41566, Republic of Korea.

Loxoprofen is a prodrug that exerts strong analgesic and anti-inflammatory effects through its active trans-alcohol metabolite, which is produced in the liver by carbonyl reductase. Previous metabolic studies have evaluated loxoprofen, but its sulfate and taurine conjugates have not yet been studied. We characterized the metabolomic profile of loxoprofen in rat plasma, urine, and feces using high-resolution mass spectrometry. We identified 17 metabolites of loxoprofen in the three different biological matrices, 13 of which were detected in plasma and feces and 16 in urine. Amongst these metabolites, two novel taurine conjugates (M12 and M13) and two novel acyl glucuronides (M14, M15) were identified for the first time in rats. In addition, we detected three novel sulfate conjugates (M9, M10, and M11) of loxoprofen. Further study of these metabolites of loxoprofen is essential in order to assess their potency and toxicity.
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http://dx.doi.org/10.1002/bdd.2196DOI Listing
July 2019

Microbial antimonate reduction with a solid-state electrode as the sole electron donor: A novel approach for antimony bioremediation.

J Hazard Mater 2019 09 27;377:179-185. Epub 2019 May 27.

Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea. Electronic address:

The anaerobic antimonate [Sb(V)] reduction with a solid-state electrode serving as the sole electron donor was demonstrated by employing a bioelectrochemical system. The highest Sb(V) reduction efficiency was observed at the biocathode potential of -0.7 V versus standard hydrogen electrode using a cathode potential range from -0.5 V to -1.1 V. The scanning electron microscopy and energy dispersive X-ray spectroscopy indicated that both amorphous and crystallized SbO were formed as products of Sb(V) reduction. The irreversible recovery of bioelectrochemical Sb(V), when the cathode potential deviated from the optimal potential, was explained through the alteration in microbial communities, which was further elucidated by the next-generation sequencing of 16S rRNA gene amplicons. Chryseobacterium koreense and Stenotrophomonas nitritireducens were the dominant species of microbial consortia at Sb(V)-reducing biocathodes. This study revealed a novel option for bioremediation of Sb at underground contaminated sites, where the delivery of organic electron donors is limited or ineffective.
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http://dx.doi.org/10.1016/j.jhazmat.2019.05.069DOI Listing
September 2019

Synthesis and Biological Evaluation of PF-543 Derivative Containing Aliphatic Side Chain.

Chem Pharm Bull (Tokyo) 2019 ;67(6):599-603

College of Pharmacy and Natural Medicine Research Institute, Mokpo National University.

The PF-543 is known as a potent and selective inhibitor of sphingosine kinase (SK) 1 amongst all the SK inhibitors known to date. In a recently reported study by Pfizer on the synthesis of PF-543 derivatives and the SK inhibitory effects, the introduction of propyl moiety into sulfonyl group of PF-543 in the case of 26b revealed an excellent result of 1.7 nM of IC of SK1, suggesting the potential substitution of chain structure for benzenesulfonyl structure. In the present work, we aimed for identification of antitumor activity and inhibitory effects of PF-543 derivative containing aliphatic long chain (similar to known SK inhibitors) on SK1. The synthesized compound 2 exhibited an inhibitory effect on SK1 in a manner similar to that of PF-543; the PF-543 derivative manifested similar antitumor activity on HT29, HCT116 (colorectal cancer cell line), and AGS (gastric cancer cell line) cells. Also, from the docking study conducted with PF-543 and compound 2, it was apparent that the aliphatic chain in compound 2 could probably replace benzenesulfonyl structure of PF-543.
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http://dx.doi.org/10.1248/cpb.c18-00724DOI Listing
June 2019

Pyruvate Dehydrogenase Kinase Is a Metabolic Checkpoint for Polarization of Macrophages to the M1 Phenotype.

Front Immunol 2019 7;10:944. Epub 2019 May 7.

BK21 Plus KNU Biomedical Convergence Programs, Department of Biomedical Science, Kyungpook National University, Daegu, South Korea.

Metabolic reprogramming during macrophage polarization supports the effector functions of these cells in health and disease. Here, we demonstrate that pyruvate dehydrogenase kinase (PDK), which inhibits the pyruvate dehydrogenase-mediated conversion of cytosolic pyruvate to mitochondrial acetyl-CoA, functions as a metabolic checkpoint in M1 macrophages. Polarization was not prevented by PDK2 or PDK4 deletion but was fully prevented by the combined deletion of PDK2 and PDK4; this lack of polarization was correlated with improved mitochondrial respiration and rewiring of metabolic breaks that are characterized by increased glycolytic intermediates and reduced metabolites in the TCA cycle. Genetic deletion or pharmacological inhibition of PDK2/4 prevents polarization of macrophages to the M1 phenotype in response to inflammatory stimuli (lipopolysaccharide plus IFN-γ). Transplantation of PDK2/4-deficient bone marrow into irradiated wild-type mice to produce mice with PDK2/4-deficient myeloid cells prevented M1 polarization, reduced obesity-associated insulin resistance, and ameliorated adipose tissue inflammation. A novel, pharmacological PDK inhibitor, KPLH1130, improved high-fat diet-induced insulin resistance; this was correlated with a reduction in the levels of pro-inflammatory markers and improved mitochondrial function. These studies identify PDK2/4 as a metabolic checkpoint for M1 phenotype polarization of macrophages, which could potentially be exploited as a novel therapeutic target for obesity-associated metabolic disorders and other inflammatory conditions.
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http://dx.doi.org/10.3389/fimmu.2019.00944DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6514528PMC
September 2020

Inhibitory Effect of KP-A038 on Osteoclastogenesis and Inflammatory Bone Loss Is Associated With Downregulation of Blimp1.

Front Pharmacol 2019 10;10:367. Epub 2019 Apr 10.

Department of Oral Pathology and Regenerative Medicine, School of Dentistry, Institute for Hard Tissue and Bio-tooth Regeneration, Kyungpook National University, Daegu, South Korea.

Excessive osteoclastic activity results in pathological bone resorptive diseases, such as osteoporosis, periodontitis, and rheumatoid arthritis. As imidazole-containing compounds possess extensive therapeutic potential for the management of diverse diseases, we synthesized a series of imidazole derivatives and investigated their effects on osteoclast differentiation and function. In the present study, we found that a novel imidazole derivative, KP-A038, suppressed receptor activator of nuclear factor-κB ligand (RANKL)-mediated osteoclastogenesis and bone-resorbing activity and attenuated lipopolysaccharide (LPS)-induced bone destruction . KP-A038 significantly inhibited the induction of nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1) and the expression of its target genes, including tartrate-resistant acid phosphatase (), cathepsin K (), dendritic cell-specific transmembrane protein (), and matrix metallopeptidase 9 (). KP-A038 upregulated the expression of negative regulators of osteoclast differentiation, such as interferon regulatory factor-8 () and B-cell lymphoma 6 (). Consistently, KP-A038 downregulated the expression of B lymphocyte-induced maturation protein-1 (Blimp1 encoded by ), a repressor for and . Moreover, administration of KP-A038 reduced LPS-induced bone erosion by suppressing osteoclast formation . Thus, our findings suggest that KP-A038 may serve as an effective therapeutic agent for the treatment and/or prevention of bone loss in pathological bone diseases, including osteoporosis and periodontitis.
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http://dx.doi.org/10.3389/fphar.2019.00367DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6467953PMC
April 2019

Screening of ten cytochrome P450 enzyme activities with 12 probe substrates in human liver microsomes using cocktail incubation and liquid chromatography-tandem mass spectrometry.

Biopharm Drug Dispos 2019 Apr 18;40(3-4):101-111. Epub 2019 Mar 18.

College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, 41566, South Korea.

Testing for potential drug interactions of new chemical entities is essential when developing a novel drug. In this study, an assay was designed to evaluate drug interactions with 10 major human cytochrome P450 (P450) enzymes incubated in liver microsomes, involving 12 probe substrates with two cocktail incubation sets used in a single liquid chromatography-tandem mass spectrometry (LC-MS/MS) run. The P450 substrate composition in each cocktail set was optimized to minimize solvent effects and mutual drug interactions among substrates as follows: cocktail A was composed of phenacetin for CYP1A2, bupropion for CYP2B6, amodiaquine for CYP2C8, diclofenac for CYP2C9, S-mephenytoin for CYP2C19, and dextromethorphan for CYP2D6; cocktail B was composed of coumarin for CYP2A6, chlorzoxazone for CYP2E1, astemizole for CYP2J2, and midazolam, nifedipine, and testosterone for CYP3A. Multiple probe substrates were used for CYP3A owing to the multiple substrate-binding sites and substrate-dependent inhibition. After incubation in human liver microsomes, each incubation mixture was pooled and all probe metabolites were simultaneously analysed in a single LC-MS/MS run. Polarity switching was used to acquire the negative-ion mode for hydroxychlorzoxazone and positive-ion mode for the remaining analytes. The method was validated by comparing the inhibition data obtained from incubation of each individual probe substrate alone and with the substrate cocktails. The half-maximal inhibitory concentration values obtained from the cocktail and individual incubations were well correlated and in agreement with previously reported values. This new method will be useful in assessing the drug interaction potential of new chemical entities during new drug development.
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http://dx.doi.org/10.1002/bdd.2174DOI Listing
April 2019

Discovery of Novel Pyruvate Dehydrogenase Kinase 4 Inhibitors for Potential Oral Treatment of Metabolic Diseases.

J Med Chem 2019 01 9;62(2):575-588. Epub 2019 Jan 9.

Department of Chemistry , Gwangju Institute of Science and Technology , Gwangju 61005 , Republic of Korea.

Pyruvate dehydrogenase kinase 4 (PDK4) activation is associated with metabolic diseases including hyperglycemia, insulin resistance, allergies, and cancer. Structural modifications of hit anthraquinone led to the identification of a new series of allosteric PDK4 inhibitors. Among this series, compound 8c showed promising in vitro activity with an IC value of 84 nM. Good metabolic stability, pharmacokinetic profiles, and possible metabolites were suggested. Compound 8c improved glucose tolerance in diet-induced obese mice and ameliorated allergic reactions in a passive cutaneous anaphylaxis mouse model. Additionally, compound 8c exhibited anticancer activity by controlling cell proliferation, transformation, and apoptosis. From the molecular docking studies, compound 8c displayed optimal fitting in the lipoamide binding site (allosteric) with a full fitness, providing a new scaffold for drug development toward PDK4 inhibitors.
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http://dx.doi.org/10.1021/acs.jmedchem.8b01168DOI Listing
January 2019

Identification of LEM-14 inhibitor of the oncoprotein NSD2.

Biochem Biophys Res Commun 2019 01 22;508(1):102-108. Epub 2018 Nov 22.

Department of Genetic Engineering, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu, 41566, Republic of Korea. Electronic address:

The NSD family (NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1) are histone lysine methyltransferases (HMTases) essential for chromatin regulation. The NSDs are oncoproteins, drivers of a number of tumors and are considered important drug-targets but the lack of potent and selective inhibitors hampers further therapeutic development and limits exploration of their biology. In particular, MMSET/NSD2 selective inhibition is being pursued for therapeutic interventions against multiple myeloma (MM) cases, especially in multiple myeloma t(4;14)(p16.3;q32) translocation that is associated with a significantly worse prognosis than other MM subgroups. Multiple myeloma is the second most common hematological malignancy, after non-Hodgkin lymphoma and remains an incurable malignancy. Here we report the discovery of LEM-14, an NSD2 specific inhibitor with an in vitro IC of 132 μM and that is inactive against the closely related NSD1 and NSD3. LEM-14-1189, a LEM-14 derivative, differentially inhibits the NSDs with in vitro IC of 418 μM (NSD1), IC of 111 μM (NSD2) and IC of 60 μM (NSD3). We propose LEM-14 and derivative LEM-14-1189 as tools for studying the biology of the NSDs and constitute meaningful steps toward potent NSDs therapeutic inhibitors.
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http://dx.doi.org/10.1016/j.bbrc.2018.11.037DOI Listing
January 2019

Synthesis of Novel FTY720 Analogs with Anticancer Activity through PP2A Activation.

Molecules 2018 Oct 24;23(11). Epub 2018 Oct 24.

College of Pharmacy and Natural Medicine Research Institute, Mokpo National University, Jeonnam 58554, Korea.

FTY720 inhibits various cancers through PP2A activation. The structure of FTY720 is also used as a basic structure for the design of sphingosine kinase (SK) inhibitors. We have synthesized derivatives using an amide chain in FTY720 with a phenyl backbone, and then compounds were screened by an MTT cell viability assay. The PP2A activity of compound was examined. The phosphorylation levels of AKT and ERK, downstream targets of PP2A, in the presence of compound , were determined. Compound may exhibit anticancer effects through PP2A activation rather than the mechanism by inhibition of SK1 in cancer cells. In the docking study of compound and PP2A, the amide chain of compound showed an interaction with Asn61 that was different from FTY720, which is expected to affect the activity of the compound.
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http://dx.doi.org/10.3390/molecules23112750DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6278267PMC
October 2018

Synthesis and Biological Evaluation of FTY720 (Fingolimod) Derivatives with Aromatic Head Group as Anticancer Agents.

Chem Pharm Bull (Tokyo) 2018 ;66(10):1015-1018

College of Pharmacy and Natural Medicine Research Institute, Mokpo National University.

FTY720 is employed for the treatment of multiple sclerosis and exerts apoptotic effects on various cancers through protein phosphatase 2A (PP2A) activation. In compound 4, the dihydroxy head group of FTY720 was modified into dihydroxy phenyl group. The cell survival in compound 4 treated colorectal and gastric cancer cells was significantly reduced as compared with control, 34.6 and 25.1%, respectively. The docking study of compound 4 showed that the aromatic head group effectively binds to PP2A.
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http://dx.doi.org/10.1248/cpb.c18-00065DOI Listing
October 2018

Characterization of CYPs and UGTs Involved in Human Liver Microsomal Metabolism of Osthenol.

Pharmaceutics 2018 Aug 30;10(3). Epub 2018 Aug 30.

BK21 Plus KNU Multi-Omics-based Creative Drug Research Team, College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Korea.

Osthenol is a prenylated coumarin isolated from the root of and , and is an -demethylated metabolite of osthole in vivo. Its various pharmacological effects have been reported previously. The metabolic pathway of osthenol was partially confirmed in rat osthole studies, and 11 metabolic products were identified in rat urine. However, the metabolic pathway of osthenol in human liver microsomes (HLM) has not been reported. In this study, we elucidated the structure of generated metabolites using a high-resolution quadrupole-orbitrap mass spectrometer (HR-MS/MS) and characterized the major human cytochrome P450 (CYP) and uridine 5'-diphospho-glucuronosyltransferase (UGT) isozymes involved in osthenol metabolism in human liver microsomes (HLMs). We identified seven metabolites (M1-M7) in HLMs after incubation in the presence of nicotinamide adenine dinucleotide phosphate (NADPH) and uridine 5'-diphosphoglucuronic acid (UDPGA). As a result, we demonstrated that osthenol is metabolized to five mono-hydroxyl metabolites (M1-M5) by CYP2D6, 1A2, and 3A4, respectively, a 7-glucuronide conjugate (M6) by UGT1A9, and a hydroxyl-glucuronide (M7) from M5 by UGT1A3 in HLMs. We also found that glucuronidation is the dominant metabolic pathway of osthenol in HLMs.
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http://dx.doi.org/10.3390/pharmaceutics10030141DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6161247PMC
August 2018

Synthesis of dansyl labeled sphingosine kinase 1 inhibitor.

Chem Phys Lipids 2018 09 22;215:29-33. Epub 2018 Jul 22.

College of Pharmacy and Natural Medicine Research Institute, Mokpo National University, Jeonnam 58554, South Korea. Electronic address:

PF-543 is a non-sphingosine analogue with inhibitory effect against SK1, based on a Ki of 4.3 nM and 130-fold selectivity for SK1 over SK2. Since the development of PF-543, animal studies demonstrated its valuable role in multiple sclerosis, myocardial infarction, and colorectal cancer. We synthesized labeled PF-543 for biochemical studies involving SK1. Overall, the 8-step synthetic route used 3,5-dimethylphenol as the starting material. A docking study of SK1 and SK1 inhibitory activity confirmed the structural similarity between the synthetic dansyl-PF-543 and PF-543. We also provide fluorescence spectra of dansyl-PF-543.
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http://dx.doi.org/10.1016/j.chemphyslip.2018.07.005DOI Listing
September 2018
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