Publications by authors named "Barbara Marzocchi"

27 Publications

  • Page 1 of 1

Machine learning application for development of a data-driven predictive model able to investigate quality of life scores in a rare disease.

Orphanet J Rare Dis 2020 02 12;15(1):46. Epub 2020 Feb 12.

Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via A., 53100, Siena, Italy.

Background: Alkaptonuria (AKU) is an ultra-rare autosomal recessive disease caused by a mutation in the homogentisate 1,2-dioxygenase (HGD) gene. One of the main obstacles in studying AKU, and other ultra-rare diseases, is the lack of a standardized methodology to assess disease severity or response to treatment. Quality of Life scores (QoL) are a reliable way to monitor patients' clinical condition and health status. QoL scores allow to monitor the evolution of diseases and assess the suitability of treatments by taking into account patients' symptoms, general health status and care satisfaction. However, more comprehensive tools to study a complex and multi-systemic disease like AKU are needed. In this study, a Machine Learning (ML) approach was implemented with the aim to perform a prediction of QoL scores based on clinical data deposited in the ApreciseKUre, an AKU- dedicated database.

Method: Data derived from 129 AKU patients have been firstly examined through a preliminary statistical analysis (Pearson correlation coefficient) to measure the linear correlation between 11 QoL scores. The variable importance in QoL scores prediction of 110 ApreciseKUre biomarkers has been then calculated using XGBoost, with K-nearest neighbours algorithm (k-NN) approach. Due to the limited number of data available, this model has been validated using surrogate data analysis.

Results: We identified a direct correlation of 6 (age, Serum Amyloid A, Chitotriosidase, Advanced Oxidation Protein Products, S-thiolated proteins and Body Mass Index) out of 110 biomarkers with the QoL health status, in particular with the KOOS (Knee injury and Osteoarthritis Outcome Score) symptoms (Relative Absolute Error (RAE) 0.25). The error distribution of surrogate-model (RAE 0.38) was unequivocally higher than the true-model one (RAE of 0.25), confirming the consistency of our dataset. Our data showed that inflammation, oxidative stress, amyloidosis and lifestyle of patients correlates with the QoL scores for physical status, while no correlation between the biomarkers and patients' mental health was present (RAE 1.1).

Conclusions: This proof of principle study for rare diseases confirms the importance of database, allowing data management and analysis, which can be used to predict more effective treatments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13023-020-1305-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7017449PMC
February 2020

Homogentisic acid affects human osteoblastic functionality by oxidative stress and alteration of the Wnt/β-catenin signaling pathway.

J Cell Physiol 2020 10 28;235(10):6808-6816. Epub 2020 Jan 28.

Dipartimento di Eccellenza in Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Siena, Italy.

Alkaptonuria (AKU) is a rare disease correlated with deficiency of the enzyme homogentisate 1,2 dioxygenase, which causes homogentisic acid (HGA) accumulation. HGA is subjected to oxidation/polymerization reactions, leading to the production of a peculiar melanin-like pigmentation (ochronosis) after chronic inflammation, which is considered as a triggering event for the generation of oxidative stress. Clinical manifestations of AKU are urine darkening, sclera pigmentation, early severe osteoarthropathy, and cardiovascular and renal complication. Despite major clinical manifestations of AKU being observed in the bones and skeleton, the molecular and functional parameters are so far unknown in AKU. In the present study, we used human osteoblasts supplemented with HGA as a AKU cellular model. We observed marked oxidative stress, and for the first time, we were able to correlate HGA deposition with an impairment in the Wnt/β-catenin signaling pathway, opening a range of possible therapeutic strategies for a disease still lacking a known cure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcp.29575DOI Listing
October 2020

Interactive alkaptonuria database: investigating clinical data to improve patient care in a rare disease.

FASEB J 2019 11 28;33(11):12696-12703. Epub 2019 Aug 28.

Department of Biotechnology, Chemistry, and Pharmacy, University of Siena, Siena, Italy.

Alkaptonuria (AKU) is an ultrarare autosomal recessive disorder (MIM 203500) that is caused byby a complex set of mutations in homogentisate 1,2-dioxygenasegene and consequent accumulation of homogentisic acid (HGA), causing a significant protein oxidation. A secondary form of amyloidosis was identified in AKU and related to high circulating serum amyloid A (SAA) levels, which are linked with inflammation and oxidative stress and might contribute to disease progression and patients' poor quality of life. Recently, we reported that inflammatory markers (SAA and chitotriosidase) and oxidative stress markers (protein thiolation index) might be disease activity markers in AKU. Thanks to an international network, we collected genotypic, phenotypic, and clinical data from more than 200 patients with AKU. These data are currently stored in our AKU database, named ApreciseKUre. In this work, we developed an algorithm able to make predictions about the oxidative status trend of each patient with AKU based on 55 predictors, namely circulating HGA, body mass index, total cholesterol, SAA, and chitotriosidase. Our general aim is to integrate the data of apparently heterogeneous patients with AKUAKU by using specific bioinformatics tools, in order to identify pivotal mechanisms involved in AKU for a preventive, predictive, and personalized medicine approach to AKU.-Cicaloni, V., Spiga, O., Dimitri, G. M., Maiocchi, R., Millucci, L., Giustarini, D., Bernardini, G., Bernini, A., Marzocchi, B., Braconi, D., Santucci, A. Interactive alkaptonuria database: investigating clinical data to improve patient care in a rare disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1096/fj.201901529RDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6902683PMC
November 2019

Homogentisic acid induces morphological and mechanical aberration of ochronotic cartilage in alkaptonuria.

J Cell Physiol 2019 05 20;234(5):6696-6708. Epub 2018 Oct 20.

Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Siena, Italy.

Alkaptonuria (AKU) is a disease caused by a deficient homogentisate 1,2-dioxygenase activity leading to systemic accumulation of homogentisic acid (HGA), that forms a melanin-like polymer that progressively deposits onto connective tissues causing a pigmentation called "ochronosis" and tissue degeneration. The effects of AKU and ochronotic pigment on the biomechanical properties of articular cartilage need further investigation. To this aim, AKU cartilage was studied using thermal (thermogravimetry and differential scanning calorimetry) and rheological analysis. We found that AKU cartilage had a doubled mesopore radius compared to healthy cartilage. Since the mesoporous structure is the main responsible for maintaining a correct hydrostatic pressure and tissue homoeostasis, drastic changes of thermal and rheological parameters were found in AKU. In particular, AKU tissue lost its capability to enhance chondrocytes metabolism (decreased heat capacity) and hence the production of proteoglycans. A drastic increase in stiffness and decrease in dissipative and lubricant role ensued in AKU cartilage. Multiphoton and scanning electron microscopies revealed destruction of cell-matrix microstructure and disruption of the superficial layer. Such observations on AKU specimens were confirmed in HGA-treated healthy cartilage, indicating that HGA is the toxic responsible of morphological and mechanical alterations of cartilage in AKU.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcp.27416DOI Listing
May 2019

A new integrated and interactive tool applicable to inborn errors of metabolism: Application to alkaptonuria.

Comput Biol Med 2018 12 5;103:1-7. Epub 2018 Oct 5.

Department of Biotechnology, Chemistry and Pharmacy (Department of Excellence 2018-2022), University of Siena, Italy. Electronic address:

This paper describes our experience with the development and implementation of a database for the rare disease Alkaptonuria (AKU, OMIM: 203500). AKU is an autosomal recessive disorder caused by a gene mutation leading to the accumulation of homogentisic acid (HGA). Analogously to other rare conditions, currently there are no approved biomarkers to monitor AKU progression or severity. Although some biomarkers are under evaluation, an extensive biomarker analysis has not been undertaken in AKU yet. In order to fill this gap, we gained access to AKU-related data that we carefully processed, documented and stored in a database, which we named ApreciseKUre. We undertook a suitable statistical analysis by associating every couple of potential biomarkers to highlight significant correlations. Our database is continuously updated allowing us to find novel unpredicted correlations between AKU biomarkers and to confirm system reliability. ApreciseKUre includes data on potential biomarkers, patients' quality of life and clinical outcomes facilitating their integration and possibly allowing a Precision Medicine approach in AKU. This framework may represent an online tool that can be turned into a best practice model for other rare diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.compbiomed.2018.10.002DOI Listing
December 2018

Novel smoothened antagonists as anti-neoplastic agents for the treatment of osteosarcoma.

J Cell Physiol 2018 06 15;233(6):4961-4971. Epub 2018 Jan 15.

Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Siena, Italy.

Osteosarcoma (OS) is an ultra-rare highly malignant tumor of the skeletal system affecting mainly children and young adults and it is characterized by an extremely aggressive clinical course. OS patients are currently treated with chemotherapy and complete surgical resection of cancer tissue. However, resistance to chemotherapy and the recurrence of disease, as pulmonary metastasis, remain the two greatest challenges in the management, and treatment of this tumor. For these reasons, it is of primary interest to find alternative therapeutic strategies for OS. Dysregulated Hedgehog signalling is involved in the development of various types of cancers including OS. It has also been implicated in tumor/stromal interaction and cancer stem cell biology, and therefore presents a novel therapeutic strategy for cancer treatment. In our work, we tested the activity of five potent Smoothened (SMO) inhibitors, four acylguanidine and one acylthiourea derivatives, against an OS cell line. We found that almost all our compounds were able to inhibit OS cells proliferation and to reduce Gli1 protein levels. Our results also indicated that SMO inhibition in OS cells by such compounds, induces apoptosis with a nanomolar potency. These findings suggest that inactivation of SMO may be a useful approach to the treatment of patients with OS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcp.26330DOI Listing
June 2018

Application of proteomics to the study of Helicobacter pylori and implications for the clinic.

Expert Rev Proteomics 2017 06 26;14(6):477-490. Epub 2017 May 26.

a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy.

Introduction: Helicobacter pylori (H. pylori) is a gram-negative bacterium that colonizes the gastric epithelium and mucous layer of more than half the world's population. H. pylori is a primary human pathogen, responsible for the development of chronic gastritis, peptic ulceration and gastric cancer. Proteomics is impacting several aspects of medical research: understanding the molecular basis of infection and disease manifestation, identification of therapeutic targets and discovery of clinically relevant biomarkers. Areas covered: The main aim of the present review is to provide a comprehensive overview of the contribution of proteomics to the study of H. pylori infection pathophysiology. In particular, we focused on the role of the bacterium and its most important virulence factor, CagA, in the progression of gastric cells transformation and cancer progression. We also discussed the proteomic approaches aimed at the investigation of the host response to bacterial infection. Expert commentary: In the field of proteomics of H. pylori, comprehensive analysis of clinically relevant proteins (functional proteomics) rather than entire proteomes will result in important medical outcomes. Finally, we provided an outlook on the potential development of proteomics in H. pylori research.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/14789450.2017.1331739DOI Listing
June 2017

Histological and Ultrastructural Characterization of Alkaptonuric Tissues.

Calcif Tissue Int 2017 07 7;101(1):50-64. Epub 2017 Mar 7.

Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy.

Alkaptonuria (AKU) is a hereditary disorder that results from altered structure and function of homogentisate 1,2 dioxygenase (HGD). This enzyme, predominantly produced by liver and kidney, is responsible for the breakdown of homogentisic acid (HGA), an intermediate in the tyrosine degradation pathway. A deficient HGD activity causes HGA levels to rise systemically. The disease is clinically characterized by homogentisic aciduria, bluish-black discoloration of connective tissues (ochronosis) and joint arthropathy. Additional manifestations are cardiovascular abnormalities, renal, urethral and prostate calculi and scleral and ear involvement. While the radiological aspect of ochronotic spondyloarthropathy is known, there are only few data regarding an exhaustive ultrastructural and histologic study of different tissues in AKU. Moreover, an in-depth analysis of tissues from patients of different ages, having varied symptoms, is currently lacking. A complete microscopic and ultrastructural analysis of different AKU tissues, coming from six differently aged patients, is here presented thus significantly contributing to a more comprehensive knowledge of this ultra-rare pathology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00223-017-0260-9DOI Listing
July 2017

Homogentisic acid induces aggregation and fibrillation of amyloidogenic proteins.

Biochim Biophys Acta Gen Subj 2017 Feb 16;1861(2):135-146. Epub 2016 Nov 16.

Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, 53100, Siena, Italy. Electronic address:

Background: Alkaptonuria (AKU) is an ultra-rare inborn error of metabolism characterized by homogentisic acid (HGA) accumulation due to a deficient activity of the homogentisate 1.2-dioxygenase (HGD) enzyme. This leads to the production of dark pigments that are deposited onto connective tissues, a condition named 'ochronosis' and whose mechanisms are not completely clear. Recently, the potential role of hitherto unidentified proteins in the ochronotic process was hypothesized, and the presence of Serum Amyloid A (SAA) in alkaptonuric tissues was reported, allowing the classification of AKU as a novel secondary amyloidosis.

Methods: Gel electrophoresis, Western Blot, Congo Red-based assays and electron microscopy were used to investigate the effects of HGA on the aggregation and fibrillation propensity of amyloidogenic proteins and peptides [Aβ(1-42), transthyretin, atrial natriuretic peptide, α-synuclein and SAA]. LC/MS and in silico analyses were undertaken to identify possible binding sites for HGA (or its oxidative metabolite, a benzoquinone acetate or BQA) in SAA.

Results: We found that HGA might act as an amyloid aggregation enhancer in vitro for all the tested proteins and peptides in a time- and dose- dependent fashion, and identified a small crevice at the interface between two HGD subunits as a candidate binding site for HGA/BQA.

Conclusions: HGA might be an important amyloid co- component playing significant roles in AKU amyloidosis.

General Significance: Our results provide a possible explanation for the clinically verified onset of amyloidotic processes in AKU and might lay the basis to setup proper pharmacological approaches to alkaptonuric ochronosis, which are still lacking.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbagen.2016.11.026DOI Listing
February 2017

Angiogenesis in alkaptonuria.

J Inherit Metab Dis 2016 11 26;39(6):801-806. Epub 2016 Sep 26.

Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via A. Moro, 2, 53100, Siena, Italy.

Alkaptonuria (AKU) is a rare genetic disease that affects the entire joint. Current standard of AKU treatment is palliative and little is known about its physiopathology. Neovascularization is involved in the pathogenesis of systemic inflammatory rheumatic diseases, a family of related disorders that includes AKU. Here, we investigated the presence of neoangiogenesis in AKU synovium and healthy controls. Synovium from AKU patients, who had undergone total joint replacement or arthroscopy, or from healthy patients without any history of rheumatic diseases, who underwent surgical operation following sport trauma was subjected to hematoxylin and eosin staining. Histologic grades were assigned for clinical disease activity and synovitis based on cellular content of the synovium. By immunofluorescence microscopy, using different endothelial cell markers, we observed large vascularization in AKU but not in healthy synovium. Moreover, Western blotting and quantification analyses confirmed strong expression of endothelial cell markers in AKU synovial tissues. Importantly, AKU synovium vascular endothelium expressed high levels of β-dystroglycan, a protein previously involved in the regulation of angiogenesis in osteoarthritic synovium. This is the first report providing experimental evidences that new blood vessels are formed in AKU synovial tissues, opening new perspectives for AKU therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10545-016-9976-3DOI Listing
November 2016

Comparative proteomics in alkaptonuria provides insights into inflammation and oxidative stress.

Int J Biochem Cell Biol 2016 12 31;81(Pt B):271-280. Epub 2016 Aug 31.

Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, 53100, Siena, Italy. Electronic address:

Alkaptonuria (AKU) is an ultra-rare inborn error of metabolism associated with a defective catabolism of phenylalanine and tyrosine leading to increased systemic levels of homogentisic acid (HGA). Excess HGA is partly excreted in the urine, partly accumulated within the body and deposited onto connective tissues under the form of an ochronotic pigment, leading to a range of clinical manifestations. No clear genotype/phenotype correlation was found in AKU, and today there is the urgent need to identify biomarkers able to monitor AKU progression and evaluate response to treatment. With this aim, we provided the first proteomic study on serum and plasma samples from alkaptonuric individuals showing pathological SAA, CRP and Advanced Oxidation Protein Products (AOPP) levels. Interesting similarities with proteomic studies on other rheumatic diseases were highlighted together with proteome alterations supporting the existence of oxidative stress and inflammation in AKU. Potential candidate biomarkers to assess disease severity, monitor disease progression and evaluate response to treatment were identified as well.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biocel.2016.08.016DOI Listing
December 2016

Cytoskeleton Aberrations in Alkaptonuric Chondrocytes.

J Cell Physiol 2017 Jul 31;232(7):1728-1738. Epub 2017 Jan 31.

Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Siena, Italy.

Alkaptonuria (AKU) is an ultra-rare autosomal genetic disorder caused by a defect in the activity of the enzyme homogentisate 1,2-dioxygenase (HGD) that leads to the accumulation of homogentisic acid (HGA) and its oxidized product, benzoquinone acetic acid (BQA), in the connective tissues causing a pigmentation called "ochronosis." The consequent progressive formation of ochronotic aggregates generate a severe condition of oxidative stress and inflammation in all the affected areas. Experimental evidences have also proved the presence of serum amyloid A (SAA) in several AKU tissues and it allowed classifying AKU as a secondary amyloidosis. Although AKU is a multisystemic disease, the most affected system is the osteoarticular one and articular cartilage is the most damaged tissue. In this work, we have analyzed for the first time the cytoskeleton of AKU chondrocytes by means of immunofluorescence staining. We have shown the presence of SAA within AKU chondrocytes and finally we have demonstrated the co-localization of SAA with three cytoskeletal proteins: actin, vimentin, and β-tubulin. Furthermore, in order to observe the ultrastructural features of AKU chondrocytes we have performed TEM analysis, focusing on the Golgi apparatus structure and, to demonstrate that pigmented areas in AKU cartilage are correspondent to areas of oxidation, 4-HNE presence has been evaluated by means of immunofluorescence. J. Cell. Physiol. 232: 1728-1738, 2017. © 2016 Wiley Periodicals, Inc.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcp.25500DOI Listing
July 2017

Inhibition of para-Hydroxyphenylpyruvate Dioxygenase by Analogues of the Herbicide Nitisinone As a Strategy to Decrease Homogentisic Acid Levels, the Causative Agent of Alkaptonuria.

ChemMedChem 2016 Apr 7;11(7):674-8. Epub 2016 Mar 7.

Department of Biotechnology, Chemistry and Pharmacy, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy.

Alkaptonuria (AKU) is a rare multisystem metabolic disease caused by deficient activity of homogentisate 1,2-dioxygenase (HGD), which leads to the accumulation of homogentisic acid (HGA). Currently, there is no treatment for AKU. The sole drug with some beneficial effects is the herbicide nitisinone (1), an inhibitor of p-hydroxyphenylpyruvate dioxygenase (4-HPPD). 1 has been used as a life-saving drug in infants with type I tyrosinemia despite severe side effects due to the buildup of tyrosine. Four clinical trials of nitisinone to treat AKU have shown that 1 consistently decreases HGA levels, but also caused the accumulation of tyrosine in blood serum. Moreover, the human preclinical toxicological data for 1 are incomplete. In this work, we performed pharmacodynamics and toxicological evaluations of 1, providing the first report of LD50 values in human cells. Intracellular tyrosinemia was also evaluated. Three additional 4-HPPD inhibitors with a more favorable profile than that of 1 in terms of IC50, LD50, and tyrosine accumulation were also identified among commercially available compounds. These may be promising starting points for the development of new therapeutic strategies for the treatment of AKU.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cmdc.201500578DOI Listing
April 2016

Chondroptosis in alkaptonuric cartilage.

J Cell Physiol 2015 May;230(5):1148-57

Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Siena, Italy.

Alkaptonuria (AKU) is a rare genetic disease that affects the entire joint. Current standard of treatment is palliative and little is known about AKU physiopathology. Chondroptosis, a peculiar type of cell death in cartilage, has been so far reported to occur in osteoarthritis, a rheumatic disease that shares some features with AKU. In the present work, we wanted to assess if chondroptosis might also occur in AKU. Electron microscopy was used to detect the morphological changes of chondrocytes in damaged cartilage distinguishing apoptosis from its variant termed chondroptosis. We adopted histological observation together with Scanning Electron Microscopy and Transmission Electron Microscopy to evaluate morphological cell changes in AKU chondrocytes. Lipid peroxidation in AKU cartilage was detected by fluorescence microscopy. Using the above-mentioned techniques, we performed a morphological analysis and assessed that AKU chondrocytes undergo phenotypic changes and lipid oxidation, resulting in a progressive loss of articular cartilage structure and function, showing typical features of chondroptosis. To the best of our knowledge, AKU is the second chronic pathology, following osteoarthritis, where chondroptosis has been documented. Our results indicate that Golgi complex plays an important role in the apoptotic process of AKU chondrocytes and suggest a contribution of chondroptosis in AKU pathogenesis. These findings also confirm a similarity between osteoarthritis and AKU.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcp.24850DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5024069PMC
May 2015

Perinatal outcome and placental histological characteristics: a single-center study.

J Matern Fetal Neonatal Med 2012 Apr 13;25 Suppl 1:110-3. Epub 2012 Mar 13.

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Siena, Italy.

Objective: Placental pathology assists in characterizing the antenatal environment and may provide information about the baby's subsequent development. We aim to assess whether histological patterns of placenta are associated with an increased risk of perinatal diseases and to evaluate how different patterns of placental dysfunction can affect the neurodevelopmental outcome.

Methods: We analyzed the histopathological characteristics of 105 singleton placentas from infants born between 23 and 31 weeks of gestation and we assessed pair-wise correlations with perinatal diseases. Estimated relative risks were calculated from odds ratios.

Results: Histological chorioamnionitis (CA group) was detected on 51 of 100 placentas tested. Lesions of uteroplacental circulation (abruption, infarction or thrombosis, perivillous fibrin deposition, syncytial knots; vasculopathy group) were detected on 29. 25 normal placentas served as controls. The incidence of bronchopulmonary dysplasia (BPD) and patent ductus arteriosus (PDA) was higher in CA than in control group. The risk of developing retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH) and PDA was higher in CA than in vasculopathy group.

Conclusions: At low gestational age CA, rather than placental lesions of vasculopathy, negatively impacts perinatal outcome. Clinical significance of histologic vasculopathy remains questionable. Other pathophysiological mechanisms than those associated with placental changes may occur following dysfunction of uteroplacental circulation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3109/14767058.2012.664344DOI Listing
April 2012

Isoprostane levels in urine of preterm newborns treated with ibuprofen for patent ductus arteriosus closure.

Pediatr Nephrol 2011 Jan 15;26(1):105-9. Epub 2010 Oct 15.

Department of Pediatrics, Obstetrics and Reproductive Medicine, Division of Neonatology, University of Siena, Siena, Italy.

Patent ductus arteriosus (PDA) is the most common cardiovascular abnormality of the preterm infant usually treated with ibuprofen (IBU). PDA is strictly related to oxidative stress (OS) in neonates. This study tests the hypothesis that OS occurs in neonates with PDA and that IBU treatment reduces OS. Forty-three preterm babies with gestational age (GA) <33 weeks were studied prospectively. Three urine samples were collected: at time 0 (before starting treatment), time 1 (after pharmacological PDA closure), and time 2 (7 days after the end of treatment) in all patients. OS was studied by measuring urinary isoprostane (IPs) levels. The results showed significant changes in urinary IP levels from time 0 to time 2 (Kruskal-Wallis, p=0.047). Time trend showed a significant decrease in IPs from time 0 to time 1 after IBU therapy (p=0.0067). This decrease was followed by an increase in IPs levels 7 days after treatment. IBU therapy for PDA closure reduced the risk of OS related to free-radical (FR) generation. This antioxidant effect of IBU may be beneficial in preterm babies with PDA who are at high risk for OS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00467-010-1651-6DOI Listing
January 2011

Oxidative damage induced by herbicides is mediated by thiol oxidation and hydroperoxides production.

Free Radic Res 2010 Aug;44(8):891-906

Dipartimento di Biologia Molecolare, Università degli Studi di Siena, via Fiorentina 1, 53100 Siena (SI), Italy.

Toxicological and environmental issues are associated with the extensive use of agricultural pesticides, although the knowledge of their toxic effects as commercial formulations is still far from being complete. This work investigated the impact of three herbicides as commercial formulations on the oxidative status of a wild type Saccharomyces cerevisiae strain. With yeast being a well-established model of eukaryotic cells, especially as far as regards the stress response, these results may be indicative of potential damages on higher eukaryotes. It was found that herbicide-mediated toxicity towards yeast cells could be the result of an increased production of hydroperoxides (like in the case of the herbicides Pointer and Silglif) or advanced oxidation protein products and lipid peroxidation (especially in the case of the herbicide Proper Energy). Through a redox-proteomic approach it was found also that, besides a common signature, each herbicide showed a specific pattern for protein thiols oxidation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3109/10715762.2010.489111DOI Listing
August 2010

Early identification of the risk for free radical-related diseases in preterm newborns.

Early Hum Dev 2010 Apr 13;86(4):241-4. Epub 2010 May 13.

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Italy.

Background: Despite recent advances in preterm newborns healthcare, perinatal pathologies and disabilities are increasing. Oxidative stress (OS) is determinant for the onset of an unbalance between free radicals (FRs) production and antioxidant systems which plays a key role in pathogenesis of pathologies such as retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), grouped as 'free radical-related diseases' (FRD).

Aim: This study tests the hypothesis that OS markers levels in cord blood may predict the onset of FRD pathologies.

Patients And Methods: 168 preterm newborns of GA: 24-32weeks (28.09+/-1.99); and BW: 470-2480 gr (1358.11+/-454.09) were consecutively recruited. Markers of potential OS risk (non-protein bound iron, NPBI; basal superoxide anion, BSA; under stimulation superoxide anion, USSA) and markers of OS-related damage (total hydroperoxides, TH; advanced oxidation protein products, AOPP) were assessed in cord blood. Associations between FRD onset and OS markers were checked through inferential analysis (univariate logistic regression).

Results: The development of FRD was significantly associated to high cord blood levels of TH, AOPP and NPBI (respectively p=0.000, OR=1.025, 95%CI=1.013-1.038; p=0.014, OR=1.092, 95%CI=1.018-1.172; p=0.007, OR=1.26995%CI=1.066-1.511).

Conclusions: Elevated levels of TH, AOPP and, above all, NPBI, in cord blood are associated with increased risk for FRD. OS markers allow the early identification of infants at risk for FRD because of perinatal oxidant exposure. This can be useful in devising strategies to prevent or ameliorate perinatal outcome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.earlhumdev.2010.03.008DOI Listing
April 2010

Effects of lutein on oxidative stress in the term newborn: a pilot study.

Neonatology 2010 7;97(1):36-40. Epub 2009 Jul 7.

Division of Neonatology, Department of Pediatrics, Obstetrics and Reproductive Medicine, Policlinico Le Scotte University of Siena, Siena, Italy.

Background: Oxidative stress (OS) plays a crucial role in pathological conditions during the early neonatal period. The newborns are susceptible to oxidative damage due to high metabolic rate and low levels of antioxidant enzymes. Lutein has been found to have protective functions in adult humans as antioxidant.

Aim: To evaluate the effects of lutein on OS in newborns. We tested the hypothesis that lutein would act both by increasing antioxidant capacity and inhibiting OS.

Methods: This was a randomized, double-blind, placebo-controlled, single-center study. 20 healthy term newborns were assigned to receive lutein or placebo (lutein and control group, respectively) at 12 and 36 h after birth. Total hydroperoxides (TH), as marker of OS, and biological antioxidant potential (BAP), as marker of antioxidant power, were detected on cord blood and at 48 h of life in all babies.

Results: TH significantly increased from birth to 48 h in the control group (p = 0.02), but not in the lutein group. In the lutein group, BAP significantly increased after 48 h (p = 0.02), showing a strengthening of antioxidant activity due to lutein. At 48 h of life, compared with those in the control group, neonates assigned to receive lutein had significantly lower TH levels (p = 0.04) and higher BAP levels (p = 0.028).

Conclusions: Lutein administration in newborns increases the levels of BAP decreasing TH. The enhancement of antioxidant activity in plasma clearly results in protecting newborn from perinatal OS. These preliminary results, adding a new contribution in antioxidant strategies, strongly require to be confirmed by RCT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000227291DOI Listing
March 2010

Biomarkers of oxidative stress in babies at high risk for retinopathy of prematurity.

Front Biosci (Elite Ed) 2009 Jun 1;1:547-52. Epub 2009 Jun 1.

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Siena, Italy.

Oxygen-induced oxidative stress (OS) has damaging effects in the perinatal period. For now there is a lake of evidence that OS occurs in babies with retinopathy of prematurity (ROP) We tests the hypothesis that a strict oxygen policy may minimize postnatal OS reducing severity of ROP. Multicenter prospective cohort study (72 newborns), using a common clinical management protocol with a strict control of oxygen administration. Assessment of biochemical markers of OS in blood samples at birth and on days 7, 14, and 21. Sixteen babies (22.2 per cent) developed ROP stage 1-2. No severe form of ROP was observed. Birth weight and O2 administration in delivery room were the factors significantly associated with the development of ROP stage 1-2. Prematurity and O2 administration in delivery room are the main factors coming into play in the course of ROP. Because room air is richer in oxygen than intrauterine environment, higher OS can be minimized, as well as incidence and severity of ROP, using standardized management with a restricted oxygen breathing policy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2741/e52DOI Listing
June 2009

Association between oxidative stress in pregnancy and preterm premature rupture of membranes.

Clin Biochem 2007 Jul 20;40(11):793-7. Epub 2007 Mar 20.

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Policlinico Le Scotte, V le Bracci 36, Siena, Italy.

Background: Premature rupture of membranes (PROM) is caused by collagen damage in the chorioamniotic sac leading to tearing. Reactive oxygen species (ROS) may be the cause of collagen damage. Isoprostanes (F(2)-IP) are produced by ROS attack on polyunsaturated fatty acids and are sensitive and specific biomarkers of lipid-peroxidation in vivo.

Aim: To verify whether oxidative stress occurs in pregnancies associated with preterm PROM.

Methods: F(2)-IPs were measured in amniotic fluid of 16 pregnancies with preterm PROM (Group II) and 97 without PROM (Group I).

Results: F(2)-IP concentrations (pg/mL) were significantly higher in group II than group I (p<0.0001). The ROC curve showed a sensitivity of 100% and a specificity of 84.5% at a cut-off of 124.4 pg/mL.

Conclusions: An association exists between oxidative stress in pregnancy and preterm PROM. The detection of amniotic fluid F(2)-IP concentrations seems to be a reliable predictive index of risk of preterm PROM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clinbiochem.2007.03.004DOI Listing
July 2007

Non-protein-bound iron detection in small samples of biological fluids and tissues.

Biol Trace Elem Res 2006 Sep;112(3):221-32

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Siena, Italy.

Interest in the pro-oxidative nature of non-protein-bound-iron (NPBI) led to the development of an assay for its detection. The aim was to set up a reliable method of detecting NPBI in small samples of biological fluids and tissue. The method was based on preferential chelation of NPBI by a large excess of the low-affinity ligand nitrilotriacetic acid. To separate NPBI, a two-step filtration procedure was used. All glassware and plasticware were treated to minimize iron contamination. Measurements were performed in plasma, amniotic fluid, bronchoalveolar lavage, and brain tissues. The analytic system detected iron as ferric nitrate standard down to a concentration of 0.01 microM. The 1,2-dimethyl-3-hydroxy-4(1H)-pyridone-Fe(DHP-Fe) complex eluted with a retention time of about 2.6 min. The standard curve for the DHP-Fe complex was linear between 0.01 and 400 microMin water as well as in plasma, bronchoalveolar lavage, brain tissue, and amniotic fluid. The detection limit was 0.01 muM for all biological fluids and brain tissue. The data show that reliable measurements of NPBI are possible in studies on oxidative stress under experimental and clinical conditions. The possibility of investigating NPBI involvement in free-radical injury might be useful in all human diseases in which oxidative stress occur.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1385/BTER:112:3:221DOI Listing
September 2006

Increased plasma concentrations of activin a predict intraventricular hemorrhage in preterm newborns.

Clin Chem 2006 Aug 1;52(8):1516-21. Epub 2006 Jun 1.

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Siena, Italy.

Background: Intraventricular hemorrhage (IVH) is a major cause of neurologic disabilities in preterm newborns. We evaluated the use of plasma activin A concentrations to predict the development of perinatal IVH.

Methods: We measured nucleated erythrocyte (NRBC) counts, plasma activin A, hypoxanthine (Hyp), and xanthine (Xan) in arterial blood samples obtained from 53 preterm infants during the first hour after birth. Cerebral ultrasound was performed within 48 h of birth and repeated at 5- or 6-day intervals until the age of 4 weeks.

Results: Grade I or II IVH was detected during the first 10 days of life in 11 of 53 patients (21%). Activin A, Hyp, and Xan concentrations and NRBC counts were higher in preterm newborns who subsequently developed IVH than in those who did not (P<0.0001, except P=0.019 for Xan). Neonatal activin A was correlated (P<0.0001) with Hyp (r=0.95), Xan (r=0.90), and NRBC count (r=0.90) in newborns without later IVH and in those who developed IVH (Hyp, r=0.89, P=0.0002; Xan, r=0.95, P<0.0001; NRBC count, r=0.90, P=0.0002). At a cutoff of 0.8 microg/L activin A, the sensitivity and specificity were 100% [11 of 11; 95% confidence interval (CI), 71%-100%] and 93% (39 of 42; 95% CI, 81%-98%), and positive and negative predictive values were 79% (95% CI, 61%-100%) and 0% (95% CI, 0%-2%), respectively. The area under the ROC curve was 0.98.

Conclusions: Activin A concentrations at birth are increased in preterm newborns who later develop IVH and may be useful for early identification of infants with hypoxic-ischemic brain insults who are at high risk for IVH.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1373/clinchem.2005.065979DOI Listing
August 2006

Nonprotein-bound iron and plasma protein oxidative stress at birth.

Pediatr Res 2005 Dec;58(6):1295-9

Department of Pediatrics, Obstetrics, and Reproductive Medicine, University of Siena, Italy.

We previously reported plasma nonprotein-bound iron (NPBI) as a reliable early indicator of intrauterine oxidative stress (OS) and brain injury. We tested the hypothesis that albumin, an NPBI serum carrier, is the major target of NPBI-induced OS. Twenty-four babies were randomly selected from 384 newborns constituting the final cohort of a prospective study undertaken to evaluate the predictive role of NPBI in cord blood for neurodevelopmental outcome. Twelve were selected in the group with lowest NPBI levels (0-1.16 microM) and good neurodevelopmental outcome and 12 in the group with highest NPBI levels (>or=15.2 microM) and poor neurodevelopmental outcome. Protein carbonyl groups were identified in cord blood samples by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and Western blotting with anti-2,4-dinitrophenyl (DNP) antibodies. Two series of immunoreactive spots, corresponding to serum albumin and alpha-fetoprotein, were found only in the group with highest NPBI levels. We found an association between NPBI and carbonylated proteins in babies with highest NPBI levels. Since NPBI may produce hydroxyl radicals through the Fenton reaction, the major target of OS induced by NPBI is its carrier: albumin. Oxidation of albumin can be expected to decrease plasma antioxidant defenses and increase the likelihood of tissue damage due to OS in the newborns.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1203/01.pdr.0000183658.17854.28DOI Listing
December 2005

Hypoxia-induced post-translational changes in red blood cell protein map of newborns.

Pediatr Res 2005 Oct;58(4):660-5

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Italy.

Tyrosine (Tyr) phosphorylation is implicated in the modification of several erythrocyte functions, such as metabolic pathways and membrane transport, as well as in signal transduction systems. Here we describe the map of Tyr-phosphorylated soluble proteins of newborn red blood cells (RBC) using an in vitro model simulating RBC reoxygenation at birth after an intrauterine hypoxic event. We tested the hypothesis that a hypoxic environment and subsequent reoxygenation promote post-translational changes in the RBC protein map of newborns, in addition to desferrioxamine (DFO)-chelatable iron (DCI) release and methemoglobin (MetHb) formation. Umbilical cord blood RBC were incubated under hypoxic conditions for 16 h at 37 degrees C, and subsequently for 8 h under aerobic conditions. Control erythrocytes were incubated under aerobic conditions at 37 degrees C for the period of the experiment, i.e. for 24 h. Tyr-phosphorylation proteins were assessed using advanced high-resolution two-dimensional electrophoresis, 2-D immunoblot analysis with anti-phosphotyrosine (anti-pTyr) antibodies, and computer-aided electrophoretogram analysis. Higher DCI release and MetHb formation were observed in newborn RBC incubated under hypoxic conditions than in those incubated aerobically. Different immunoreactivity patterns with anti-pTyr antibodies were also observed between newborn RBC incubated under hypoxic conditions and controls. A hypoxic environment is a factor promoting DCI release, a well-known condition of oxidative stress. This is the first map of Tyr-phosphorylated soluble proteins of newborn RBC obtained using an in vitro model simulating RBC reoxygenation at birth after an intrauterine hypoxic event. Our results suggest that hypoxia increases Tyr-phosphorylation of antioxidant proteins, protecting RBC against oxidative stress.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1203/01.PDR.0000180545.24457.ACDOI Listing
October 2005

Isoprostanes in amniotic fluid: a predictive marker for fetal growth restriction in pregnancy.

Free Radic Biol Med 2005 Jun;38(11):1537-41

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Policlinico Le Scotte, V.le Bracci 36, 53100 Siena, Italy.

Isoprostanes are markers of free radical-catalyzed lipid peroxidation. Evidence suggests that oxidative stress occurs in pregnancies with fetal growth restriction (FGR). The aim of this study was to analyze F2-isoprostanes in amniotic fluid of FGR pregnancies. We tested the hypothesis that F2-isoprostanes are reliable markers to distinguish FGR pregnancies from normal ones and appropriate-for-gestational-age (AGA) from small-for-gestational-age (SGA) newborns. F2-isoprostanes levels were measured by colorimetric enzyme immunoassay in the amniotic fluid of 77 pregnancies with normal fetal growth (group I) and 37 with FGR (group II). Fetal biometry and Doppler measurements were obtained using an ATL HDI 3000 ultrasound system. Isoprostanes were higher in group II than group I. The ROC curve distinguished group I from group II, showing 100% sensitivity and 88.3% specificity at a cutoff of 94 pg/ml. There were no statistical differences in isoprostanes levels between AGA and SGA newborns in group II. The area under the ROC curve drawn to distinguish AGA and SGA newborns showed a sensitivity of 100% and a specificity of 72.3% at a cutoff of 94 pg/ml. The relative risk index indicated a 8.05 times higher risk of birth weight below the 3rd percentiles in group II than in group I. High isoprostanes concentrations can be detected in the amniotic fluid of FGR pregnancies and the assay of isoprostanes in amniotic fluid is a reliable assessment of fetal oxidative stress. Common use of this predictive marker in obstetrics will improve the ability of clinicians to identify those fetuses who will be born SGA or with a birth weight below the 25th percentile.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.freeradbiomed.2005.02.017DOI Listing
June 2005

Oxidative stress in preterm neonates at birth and on the seventh day of life.

Pediatr Res 2002 Jul;52(1):46-9

Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, 53100 Siena, Italy.

Previous studies have demonstrated increased oxidative damage to proteins and increased lipid peroxidation products in the plasma of hypoxic newborns at birth. We tested the hypothesis that hypoxic preterm newborns are at increased risk for oxidative stress in the first week of life. Heparinized blood samples of 34 hypoxic and 15 control preterm newborns were obtained at birth from the umbilical vein immediately after delivery and from a peripheral vein on postnatal d 7. Plasma levels of hypoxanthine, total hydroperoxide (TH), and advanced oxidation protein products (AOPP) were measured in cord blood and blood drawn on d 7. Hypoxanthine, TH, and AOPP levels were significantly higher in cord and d 7 blood samples of hypoxic newborn than control infants. Statistically significant correlations were observed between AOPP and hypoxanthine and between AOPP and TH plasma levels on d 7. AOPP and TH plasma levels significantly increased from cord to d 7 blood in neonates without hypoxia. These findings show that the oxidative stress observed in cord blood of hypoxic preterm newborns is still higher than control infants on d 7. The significant increase in TH and AOPP levels in nonhypoxic preterm newborns at the end of the first postnatal week indicates that damage caused by free radicals also occurs in nonhypoxic babies with normal clinical course. In summary, TH and AOPP production is prolonged for several days after birth in hypoxic preterm babies. The risk of free radical damage is lower but still exists in preterm neonates with normal clinical course.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1203/00006450-200207000-00010DOI Listing
July 2002