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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Maternal nonalcoholic fatty liver disease: A driver of fetal hepatic steatosis?

Klepper, Corie 23 August 2022 (has links)
No description available.
82

Third Trimester Plasma Metabolites Associated with Gestational Diabetes: An Ancillary Analysis of the Healthy Beginnings Trial

Rosario, Rodrigo D 01 September 2021 (has links) (PDF)
Introduction: Gestational Diabetes Mellitus (GDM) results in complications affecting both mother and child. The implementation of metabolomics to assess metabolite alterations is needed to better understand its etiology. Prior research by our lab in first trimester samples of GDM patients indicated altered fatty acid utilization and purine degradation products. Objective: Metabolomics analysis was conducted on third trimester (28 -35 weeks) plasma samples to observe differences associated with GDM. Methods: Fifty samples taken from the Healthy Beginnings trial and their corresponding data were included in the study. Plasma samples were analyzed using UPLC-MS with metabolomic assays for primary metabolomics, aminomics, and lipidomics. Plasma metabolite comparisons were made between participants who developed GDM (n=27) and individuals without GDM (n=23) through UPLC-MS analysis with metabolomic assays for primary metabolomics, aminomics, and lipidomics. Dietary intake was collected via 24 hour recalls to assess dietary differences between groups. Results: Fatty acid oxidation-related metabolites altered included lower decanoyl-, dodecenoyl-, and lauroyl-carnitine (p Conclusion: In support of previous research in first trimester samples, metabolomics revealed altered markers of fatty acid metabolism and purine degradation in GDM patients. Further research is necessary to validate these findings and identify the key roles these metabolites may play in GDM development. Keywords: Gestational diabetes mellitus, metabolomics, acylcarnitines, purines
83

Cell Membrane Lipid Alterations In Blood Plasma At Pre-Conception And During Pregnancy Are Associated With Gestational Diabetes Development

Luevano, Jennifer J 01 October 2023 (has links) (PDF)
Introduction: Gestational diabetes mellitus (GDM) is a metabolic disorder that has been defined as glucose intolerance that is first identified during pregnancy. The etiology of GDM is not yet fully understood, but there are several risk factors that appear to contribute to its development such as advanced age at pregnancy, family history of type 2 diabetes mellitus, and a previous history of GDM. The discovery of predictive GDM biomarkers has the potential to enable early GDM detection and lead to earlier diagnosis and preventative interventions. Objective: Perform metabolomics analysis on plasma samples collected at pre-conception and at 26-weeks gestation to investigate metabolic differences between participants of the gestational diabetes prevention (GDP) clinical trial who developed GDM and those who did not. Methods: Targeted metabolomics, comprised of primary metabolomics, biogenic amines, and lipidomics assays, was performed using UPLC-MS on plasma samples collected from a subset of 30 participants that completed the GDP study at preconception and 26 weeks gestation. The samples used for this analysis were from participants who developed GDM (n=19) and those who did not (n=11) in their pregnancy following their participation in the GDP study. Results: Multivariate analysis revealed indoxyl sulfate as significantly higher in the GDM group at both preconception and at 26 weeks gestation (VIP scores > 2.9). Preconception samples collected at the end of the GDP intervention study PC 38:0 was higher in the GDM group versus the non-GDM group (p < 0.05) whereas thymidine was lower in the GDM group (p < 0.05), in addition to numerous cell membrane lipids (VIP > 2.0). At 26 weeks gestation, D-glucuronic acid was higher in the GDM group versus the non-GDM group (p < 0.03), while LPE 22:6, SM 18:1 (22:4), PE 38:6, PE 40:6, PE 40:7, and PE (O-38:0) were lower in the GDM group (p < 0.04), in addition to numerous cell membrane lipids (VIP > 2.0). Discussion: The differences observed between the GDM and non-GDM groups at the two plasma collection time points may suggest metabolic alterations associated with GDM-induced metabolic dysregulation. These findings may help direct future research to focus on changes in lipid metabolism during pre-pregnancy for possible biomarkers of GDM. Repeat studies with diverse cohorts are needed to help identify a panel of metabolites that may serve as early biomarkers of GDM.
84

Lifestyle and personal predictors of pregnancy-induced hypertension and gestational diabetes

Zhou, Xinyi 13 June 2023 (has links)
BACKGROUND: Pregnancy-induced hypertension (PIH) and gestational diabetes mellitus (GDM) are among the leading causes of disability and death for women and their babies. Identifying risk factors for these pregnancy-related complications is essential to their prevention. Studies identifying preventive models for PIH and GDM are few. OBJECTIVES: This study was designed to evaluate lifestyle and personal predictors of PIH and GDM in a cohort of nearly 20,000 pregnant women. METHODS: The exposure data for the study were derived from a combination of a telephone interview and a questionnaire completed approximately 2 months after conception during the period from 1984 to 1987. The initial questionnaires asked for information on three periods: 3 months before conception, at conception, and 2 months after conception. Subjects included 19,312 women, aged 18-<45 years, who did not have excessive intakes of alcohol or food, were neither underweight (BMI >18.5) nor extremely overweight (BMI <40), and did not use illegal drugs during the first trimester of pregnancy. Outcome data on the mother and baby were collected approximately one year after the expected data of delivery. Logistic regression models were used to estimate the odds ratios (OR), and 95% confidence intervals (CI), as well as receiver operating characteristic (ROC) curves predicting PIH and GDM. Akaike Information Criteria (AIC) were used to select the best predictors of these two outcomes. Factors found not to affect PIH or GDM (based on a two-unit decrease in the AIC) were excluded from the final models. RESULTS: Based on the outcome data collected, there were 204 PIH cases, 358 GDM cases, and 538 who had PIH and/or GDM. After selecting the outcome predictors using AIC values, we identified three predictive models—one each for PIH, GDM, and either PIH or GDM. Factors found to predict PIH included age, previous hypertension or type 1 or 2 diabetes, pre-pregnancy BMI, parity, exercise, red meat consumption, margarine consumption, cigarette smoking, and weight change at 2 months. The final AIC value for PIH was 2084.12 and the AUC value was 0.76. GDM was predicted by age, previous GDM (in an earlier pregnancy), pre-pregnant BMI, height, exercise, race, dairy consumption, and cigarette smoking, with an AIC value of 3288.74 and an AUC value of 0.70. The combined model (predicting either PIH or GDM) was best predicted by age, history of GDM in a previous pregnancy, pre-pregnant BMI, previous history of hypertension, height, exercise, dairy consumption, red meat consumption, parity numbers, cigarette smoking, and weight change at 2 months with an AIC value of 3288.74 and an AUC value of 0.71. CONCLUSIONS: In these analyses, separate models predicting PIH and GDM were better than a combined model predicting PIH or GDM. These final models indicate that we can reasonably identify women who are at increased risk for adverse maternal outcomes associated with hypertensive disorders or diabetes during pregnancy.
85

THE IMPACT OF MATERNAL AND/OR NEWBORN GENETIC RISK SCORES ON MATERNAL AND NEWBORN DYSGLYCEMIA / MATERNAL AND NEWBORN GENETIC RISK SCORE AND DYSGLYCEMIA

Limbachia, Jayneel January 2019 (has links)
Background: South Asians are at an increased risk of developing dysglycemia during and after pregnancy. In pregnant women, dysglycemia often develops in the form of gestational diabetes mellitus (GDM), which may predispose their newborns to adverse health outcomes through abnormal cord blood insulin levels. However, reasons for the elevated risk of dysglycemia in South Asians have not been extensively studied. Genetic factors may contribute to the heritability of GDM and abnormal cord blood insulin levels in South Asians. Objectives: The objectives of this thesis were to test the association of: 1) A type 2 diabetes polygenic risk score with GDM in South Asian pregnant women from the South Asian Birth Cohort (START); 2) maternal and newborn insulin-based polygenic risk scores with cord blood insulin and glucose/insulin ratio in South Asian newborns from START Methods: Three polygenic risk scores were created to test their association with participant data (N=1012) from START. GDM was defined using cut-offs established by the Born in Bradford cohort of South Asian women. The type 2 diabetes polygenic risk score was created in 832 START mothers and included 35,274 independent variants. The maternal and newborn insulin-based polygenic risk scores were created in 604 START newborns and included 1128017 independent variants. Univariate and multiple logistic and linear regression models were used to test the associations between the polygenic risk scores and dysglycemia outcomes. Results: The type 2 diabetes polygenic risk score was associated with GDM in both univariate (OR: 2.00, 95% CI: 1.46-2.75, P<0.001), and multivariable models (OR: 1.81, 95% CI: 1.30-2.53, P<0.001). The maternal insulin-based polygenic risk score was not associated with cord blood insulin or cord glucose/insulin ratio. However, the newborn insulin-based polygenic risk score was associated with cord blood insulin in a multivariable model adjusted for maternal insulin-based polygenic risk score (β = 0.036, 95% CI: 0.002 – 0.069; P=0.038 among other factors. Conclusion: A type 2 diabetes polygenic risk score and a newborn insulin-based polygenic risk score may be associated with maternal and newborn dysglycemia. / Thesis / Master of Science (MSc) / Background: South Asians are approximately two times more at risk for developing gestational diabetes mellitus (GDM) compared to white Caucasians. Genetic factors may contribute to this elevated risk. Polygenic risk scores (PRSs), which combine the effects of multiple disease loci and variants associated with the disease into one variable could be useful in further understanding how GDM develops in South Asians. Methods: Data from the South Asian Birth Cohort (START) was used to test the association of three PRSs with the outcomes of interest. Results: The type 2 diabetes PRS was independently associated with GDM. The insulin-based maternal PRS was not associated with cord blood insulin but the insulin-based newborn PRS was independently associated with cord blood insulin. However, neither the insulin-based maternal nor newborn PRS was associated with cord blood glucose/insulin ratio. Conclusion: The PRSs suggests a possible genetic component, which contributes to abnormal glycemic status development in South Asian mothers and their newborns.
86

High Saturated Fat Diet Induces Gestational Diabetes, Perinatal Skeletal Malformation and Adult-Onset Chronic Diseases

Liang, Chengya 22 April 2009 (has links)
Adult exposure to high fat diet (HFD) has been linked to increased risk of musculoskeletal, cardiovascular, and metabolic diseases; however, the contribution of gestational HFD to elevated oxidative stress (OS), perinatal cardiovascular, skeletal, and metabolic dysfunction as well as long-term effects on adult offspring are incompletely understood. Pathophysiologic mechanisms linking gestational HFD, OS, and insulin resistance to perinatal development and adult-onset chronic diseases are explored in the present study, and maternal antioxidant (quercetin) is offered as a potential preventive dietary supplement to reduce fetal and maternal sequelae of HFD. Female C57BL/6 mice were fed "cafeteria-style" HFD (including 32.1% saturated fat to mimic a typical fast food menu) with or without quercetin for one month prior to conception, and throughout gestation. HFD dams developed gestational diabetes with significantly increased placental OS and vasculopathy. Neonates were smaller at birth than age-matched controls, and surviving offspring developed type 2 diabetes, hypertension and osteoporosis during adulthood, despite having been fed healthy diet throughout their postnatal life. Additional measures of bone using three-dimensionally reconstructed computed tomographic image analysis (microCT) revealed microarchitectural changes of bone at birth, and at 6 and 12 months postnatally. Fetuses from HFD dams displayed diminished bone mineral density (BMD) and disrupted endochondral and intramembranous ossification with significantly shortened distal limb lengths, as compared to offspring of standard rodent chow dams. Skeletal malformation persisted into adulthood despite the fact that both control and HFD offspring were fed conventional rodent chow throughout postnatal life. The offspring gestationally exposed to HFD showed significant decreased femoral BMD at 6 months of age and dysregulation of distal femoral trabecular architecture at 12 months of age, indicating development of osteoporosis. We were able to reduce incidence of placental vasculopathy, fetal maldevelopment and adult-onset type 2 diabetes, hypertension and osteoporosis with concurrent maternal quercetin supplementation during pregnancy. Collectively, these data suggested that maternal HFD increases placental OS and vascular damage during pregnancy, which are associated with fetal malformation and elevated adult-onset multisystemic chronic diseases. Maternal quercetin supplementation must be further explored as a potential dietary intervention for improved placental integrity, fetal development and lifelong health. / Ph. D.
87

Dépistage précoce du diabète gestationnel / Early screening of gestational diabetes mellitus

Mahdavian, Masoud January 2015 (has links)
Résumé : L’aggravation de certaines caractéristiques cliniques des femmes enceintes (âge, poids) et l’augmentation de la prévalence du diabète gestationnel (DG) poussent à dépister le DG le plus tôt possible pour éviter chez la mère et le fœtus les complications à court et à long terme. Le dépistage du DG est recommandé à 24-28 semaines de grossesse, et le plus souvent un test de tolérance à 50g de glucose (TTG) est réalisé. Pour les femmes qui ont des facteurs de risque, ce test doit être effectué plus précocement, habituellement pendant le premier trimestre de la grossesse. Cette dernière recommandation est peu suivie, d’autant qu’il n’y a pas de consensus international sur le dépistage du DG pendant le premier trimestre de la grossesse. Objectifs. 1) Définir au premier trimestre de la grossesse la valeur de la glycémie du TTG qui prédit le diagnostic de DG à 24-28 semaines avec une sensibilité et une spécificité optimales à l’aide d’une courbe ROC. 2) Déterminer si la glycémie du TTG au premier trimestre est un facteur prédictif indépendant du DG. Méthodes. Étude prospective de cohorte. Les facteurs d'inclusion étaient : âge ≥ 18 ans et âge gestationnel entre 6 et 13 semaines après la dernière menstruation. Les TTG ont été effectués à la première visite prénatale. Une deuxième visite était programmée à 24-28 semaines pour faire une hyperglycémie provoquée par voie orale (HGPO) et donc un éventuel diagnostic de DG. Les critères utilisés pour ce diagnostic étaient ceux de l’Association américaine du diabète. Résultats. Les TTG ont été faits à 9,1±2,0 semaines et les HGPO à 26.5±1.1semaines chez 1180 femmes (28,2±4,4 ans, IMC : 25,2±5,5 kg/m[indice supérieur 2]). Un DG a été diagnostiqué chez 100 (8,4%) participantes. La valeur de glycémie du TTG à 5,6 mmol/L a prédit le DG avec une sensibilité de 84,1% et une spécificité de 62,3%, tandis que la valeur prédictive positive était de 0,121 et la valeur prédictive négative de 0,985. Cette valeur de 5,6 était indépendamment associée au DG (OR=2,806, IC 95%: 1,98 à 3,97, p <0,001). Comparé à d'autres facteurs de risque, le TTG était le plus puissant prédicteur indépendant du DG (OR=1,767, IC 95%: 1,52 à 2,05, p <0,001). Conclusions. Au premier trimestre, la valeur glycémie de 5.6 mmol/L du TTG prédit avec une bonne sensibilité et spécificité l’apparition d’un DG à 24-28 semaines. La glycémie du TTG au premier trimestre est le plus puissant prédicteur indépendant de DG. / Abstract : The changes in clinical characteristics of pregnant women and an increase in the prevalence of gestational diabetes mellitus (GDM) warrant the importance of screening as early as possible in order to possibly prevent short and long-term complications in both the mother and fetus. GDM screening is recommended at 24-28 weeks of pregnancy, using a 50g glucose challenge test (GCT) although women with multiple risk factors are expected to be assessed “early” in pregnancy, a recommendation poorly followed. Most importantly, there is no universal agreement currently in place for GDM screening, particularly during the first trimester of pregnancy. Objectives. 1) To define the cut-off value of GCT during the first trimester in order to predict GDM diagnosed at 24-28 weeks of gestation with optimal sensitivity and specificity using ROC curve. 2) To determine if GCT during the first trimester of pregnancy is an independent predictor of GDM diagnosed at 24-28 weeks gestation. Methods. This is a prospective cohort study. Women were recruited at their first prenatal visit. Inclusion factors were: age ≥ 18 years and gestational age between 6 and 13 weeks from their last menstrual period. GCT were performed at the first prenatal visit. The second visit was scheduled at 24-28 weeks for the diagnostic 75g oral glucose tolerance test (OGTT). GDM diagnosis was made in accordance with the American Diabetes Association guidelines. A variety of statistical analysis including multivariate logistic regression models and ROC curve were used to address the aims of the study. Results. Participants (n=1180, age: 28.2±4.4 years, BMI: 25.2±5.5 kg/m[superscript 2]) underwent GCT at 9.1±2.0 weeks and OGTT at 26.5±1.1 weeks of gestation. GDM was diagnosed in 100 (8.4%) women. The cut-off value of 5.6 mmol/L predicted GDM with 84.1% (75.4-92.7) sensitivity, 62.3% (59.5-65.1) specificity, while the positive predictive value was 0.121 (0.091-0.150) and the negative predictive value was 0.985 (0.975-0.994). This 5.6 value was independently associated with GDM (OR=2.806, 95% CI: 1.98-3.97, p<0.001). Compared to other risk factors, GCT was the strongest independent predictor of GDM (OR=1.767, 95% CI: 1.52-2.05, p<0.001). Conclusions. The cut-off value of 5.6 mmol/L has the optimal sensitivity and specificity for the GCT during the first trimester to predict GDM at 24-28 weeks of gestation according to ADA guidelines. GCT during the first trimester is the strongest independent predictor of GDM at 24-28 weeks of gestation.
88

Discourses pertaining to, and lived experiences of, 'Maternal Obesity' (Body Mass Index (BMI) ≥ 30) and Gestational Diabetes Mellitus/Type Two Diabetes Mellitus in the pregnancy and post-birth period

Jarvie, Rachel Juliet January 2014 (has links)
This thesis reports on a qualitative exploration of the experiences of 30 women designated as ‘high risk’ due to the co-existence of ‘maternal obesity’ (BMI ≥ 30) and Gestational Diabetes Mellitus (GDM)/Type Two Diabetes Mellitus (T2DM) in pregnancy. This is examined in the context of medico-scientific/public health/ popular media discourses pertaining to ‘maternal obesity’/GDM/T2DM in pregnancy. ‘Maternal obesity’/GDM/T2DM in pregnancy are increasingly prevalent and clinically associated in manifold ways. Increasing prevalence is linked to the ‘global epidemic’ of ‘obesity’/diabetes: now commonly referred to as ‘diabesity’. Current biomedical knowledge asserts ‘maternal obesity’ and diabetes (‘maternal diabesity’) synergise in causing adverse pregnancy outcomes, have long term health implications for the offspring and contribute to an ‘intergenerational cycle’ of ‘obesity’/diabetes. This is the first qualitative study to consider pregnancy/post-birth experiences of women with co-existing ‘maternal obesity’ and GDM/T2DM in pregnancy from a sociological perspective. Participants undertook a series of auto/biographical narrative interviews. Longitudinal engagement provided nuanced psycho-social insight into women’s perceptions/experiences and the socio-cultural context of their lives. Analysis of pertinent ‘pregnancy’ Internet fora postings augmented interview data and was utilised for comparative/corroborative purposes. Participants were predominantly of low socio-economic status, congruent with epidemiological data. The concept of pregnancy ‘planning’ was not resonant and few women accessed/felt predisposed to access preconception care. Women did not identify as ‘obese’, and knowledge/perception of risks associated with the medical ‘conditions’ was low. Women perceived themselves to be stigmatised due to their weight in society and specifically within healthcare. Many participants were experiencing acute/chronic stress which appeared to have mediated risk perceptions/compromised diabetic regimen adherence. Expense of ‘healthy’ eating/diabetic diet was considered prohibitive. Women’s material circumstances/socio-cultural milieux may militate against ability to minimise risk and effect lifestyle change. Policy and practice, for the most part, fails to take this into account.
89

Die Regulation von Preadipocyte factor-1 bei Gestationsdiabetes mellitus und Präeklampsie

Wurst, Ulrike 19 December 2016 (has links) (PDF)
Adipositas und die damit verbundenen Begleiterkrankungen zeigen einen deutlichen Anstieg der Prävalenz in der Bevölkerung. Auch für die Schwangerschaft gilt starkes Übergewicht als Risikofaktor für metabolische und vaskuläre Komplikationen wie Gestationsdiabetes mellitus (GDM) und Präeklampsie (PE). In den letzten 20 Jahren wurde eindrücklich nachgewiesen, dass eine Dysregulation von Fettzell-sezernierten Proteinen, sogenannten Adipokinen, ursächlich zu GDM und PE beitragen könnte. Zu Beginn der Dissertation lagen jedoch nur unzureichende Daten über die Regulation des Insulinresistenz-induzierenden, anti-adipogenen und anti-angiogenen Adipokins Preadipocyte factor-1 (Pref-1) bei GDM und PE vor. Die vorliegende Arbeit untersucht daher die Regulation von zirkulierendem Pref-1 bei GDM und PE sowie seine Expression in der Plazenta. Bei 74 Patientinnen mit GDM konnte kein signifikanter Unterschied der Pref-1 Konzentrationen (0.40 µg/l) verglichen zu 74 Gesunden (0.42 µg/l) (p = 0.655) festgestellt werden (Wurst U et al., Cytokine 2015; 71: 161–164). Es zeigte sich in der Kohorte eine unabhängige Assoziation zwischen Pref-1 und Schwangerschaftsalter bei der Blutentnahme, Triglyzeriden, Kreatinin, Body Mass Index und C reaktivem Protein (p < 0.05). In einer Studienkohorte von 51 Schwangeren mit PE wurden signifikant niedrigere Serumspiegel von Pref-1 (0.49 µg/l) im Vergleich zu 51 gesunden Schwangeren (0.68 µg/l) (p < 0.001) gemessen (Schrey S, Wurst U, et al., Cytokine 2015; 75: 338–343). In der multiplen Regressionsanalyse waren PE, Schwangerschaftsalter zum Zeitpunkt der Blutentnahme sowie zirkulierendes Leptin unabhängige Prädiktoren für Pref-1. Im peripartalen Zeitraum zeigte sich ein akuter und deutlicher Abfall von zirkulierendem Pref-1 im mütterlichen Blut und das Adipokin wurde immunhistochemisch im Plazentagewebe nachgewiesen. Die Daten dieser Studien sind vereinbar mit den Hypothesen, dass Pref-1 mit fortschreitender Schwangerschaft zunehmend produziert wird, die Plazenta zur Sekretion des Adipokins aktiv beiträgt sowie das Adipokin bei PE dysreguliert ist. Weiterführende Untersuchungen im Tiermodell sowie prospektive Studien sind notwendig, um die Signifikanz von Pref-1 bei GDM und PE näher zu untersuchen.
90

Efeito da progesterona na expressão de genes envolvidos no estresse oxidativo e defesa antioxidante em células beta pancreáticas: uma abordagem in vitro para o estudo do diabetes gestacional / Progesterone effect on the genes expression involved on oxidative stress and antioxidant defense in pancreatic beta cells: an in vitro approach to the study of gestational diabetes

Borçari, Nathalia Ruder 16 March 2018 (has links)
O diabetes gestacional (DG) é uma condição definida como intolerância a carboidratos e hiperglicemia, com início no segundo trimestre da gravidez. Trabalhos desenvolvidos por nosso grupo mostraram que a progesterona (PG) é capaz de causar a morte de células pancreáticas, por um mecanismo dependente da geração de radicais livres, o que poderia contribuir para o desenvolvimento do DG. O objetivo desse trabalho foi estudar o efeito da PG, na presença ou não de antioxidantes, na expressão de genes relacionados ao estresse oxidativo e na defesa oxidante em células pancreáticas da linhagem RINm5F. As células foram incubadas com PG 0,1, 1,0 e 100 &#181M por 6 ou 24 h, na presença ou não dos antioxidantes vitamina E e C. Após a incubação, foram realizados ensaios de viabilidade celular e fragmentação do DNA. A PG, não causou perda da integridade da membrana das células RINm5F, porém, ela promoveu fragmentação do DNA em, aproximadamente, 40% das células RINm5F e MCF-7 (controle positivo), enquanto que os antioxidantes vitamina E e C reduziram tal fragmentação. A partir da extração do RNA e síntese de cDNA foi investigada a expressão de 84 genes envolvidos no estresse oxidativo e defesa antioxidante. Dos 84 genes, cinco deles tiveram sua expressão aumentada em no mínimo, duas vezes em, pelo menos, duas concentrações diferentes, independentemente do tempo de incubação, ou nas mesmas concentrações em tempos diferentes, como os que codificam para a proteína de choque térmico a1a (Hspa1a), glutationa peroxidase 6 (Gpx6), dual oxidase 1 (Duox1), heme oxigenase 1(Hmox1) e estearoil-CoA desaturase 1 (Scd1). Esses genes, juntamente com a peroxirredoxina 4 (Prdx4), desempenham importante papel na fisiologia da célula pancreática e/ou DG. A expressão desses genes também foi estudada na pré-incubação das células RINm5F com as vitaminas E e C. Tais antioxidantes, de forma geral, foram capazes de aumentar a expressão de Hmox1 e Prdx4, genes com funções antioxidantes, e de diminuir de Scd1, um gene com função pró- oxidante. Ao nível citoplasmático, verificou-se que as quantidades das proteínas Hmox1 e Prdx4 também foram moduladas pela da PG e/ou vitamina E e C. Os resultados sugerem que esses antioxidantes apresentam importante papel na proteção da células RINm5F contra o dano oxidativo induzido pela PG. Desta forma, os resultados obtidos nesse projeto, em conjunto, devem colaborar para melhor compreensão da patogênese do DG, abrindo novas perspectivas não só para elucidação do mecanismo molecular envolvido na ação da PG sobre células pancreáticas e sua relação com o DG, mas para o desenvolvimento de estratégias de prevenção e tratamento dessa doença baseadas na terapia com antioxidantes / Gestational diabetes (GD) is a condition defined as carbohydrate intolerance and hyperglycemia, beginning in the second trimester of pregnancy. Studies developed by our group have shown that progesterone (PG) is able to cause pancreatic cells death, by a mechanism dependent on the generation of free radicals, which could contribute to the development of GD. The aim of this work was to study the effect of PG, in the presence or absence of antioxidants, on the expression of genes related to oxidative stress and oxidant defense in pancreatic cells of the RINm5F lineage. Cells were incubated with 0.1, 1.0 and 100 µM PG for 6 or 24 h, in the presence or absence of vitamin E and C antioxidants. PG did not cause loss of membrane integrity of RINm5F cells, however, it promoted DNA fragmentation in approximately 40% of the RINm5F and MCF-7 cells (positive control), whereas vitamin E and C antioxidants reduced such fragmentation. From the RNA extraction and cDNA synthesis was investigated the expression of 84 genes involved in oxidative stress and antioxidant defense. Among of 84 investigated genes, five of them had their expression increased, in the minimum 2-fold in, at least, two different concentrations independent of incubation time (6 or 24 h), or at the same concentrations at different times, such as those that encoding for heat shock protein a1a (Hspa1a), glutathione peroxidase 6 (Gpx6), dual oxidase 1 (Duox1), heme oxygenase 1 (Hmox1) and stearoyl-CoA denaturase 1 (Scd1). These genes, together with the peroxiredoxin 4 (Prdx4), play an important role in pancreatic cell physiology and/or DG. The gene expression was also studied in the preincubation of RINm5F cells with vitamin E and C. These antioxidants were generally able to increase the Hmox1 and Prdx4 expression, genes with antioxidant functions, and decrease the Scd1 expression, a gene with pro-oxidant function. At the cytoplasmic level, it was found that the amounts of Hmox1 and Prdx4 proteins were also modulated by PG and / or vitamin E and C. The results suggest that these antioxidants play an important role in the RINm5F protection cells against the oxidative damage induced by PG. Thus, the results obtained in this project, together, should contribute to a better understanding of the pathogenesis of DG, opening new perspectives not only to elucidate the molecular mechanism involved in the action of PG on pancreatic cells and its relationship with DG, but for the development of strategies for the prevention and treatment of this disease based on antioxidant therapy

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