Identification of the SIRT1 gene's most harmful non-synonymous SNPs and their effects on functional and structural features-an in silico analysis.

Introduction: The sirtuin (Silent mating type information regulation 2 homolog)1(SIRT1) protein plays a vital role in many disorders such as diabetes, cancer, obesity, inflammation, and neurodegenerative and cardiovascular diseases. The objective of this in silico analysis of SIRT1's functional single nucleotide polymorphisms (SNPs) was to gain valuable insight into the harmful effects of non-synonymous SNPs (nsSNPs) on the protein. The objective of the study was to use bioinformatics methods to investigate the genetic variations and modifications that may have an impact on the SIRT1 gene's expression and function. Methods: nsSNPs of SIRT1 protein were collected from the dbSNP site, from its three (3) different protein accession IDs. These were then fed to various bioinformatic tools such as SIFT, Provean, and I- Mutant to find the most deleterious ones. Functional and structural effects were examined using the HOPE server and I-Tasser. Gene interactions were predicted by STRING software. The SIFT, Provean, and I-Mutant tools detected the most deleterious three nsSNPs (rs769519031, rs778184510, and rs199983221). Results: Out of 252 nsSNPs, SIFT analysis showed that 94 were deleterious, Provean listed 67 dangerous, and I-Mutant found 58 nsSNPs resulting in lowered stability of proteins. HOPE modelling of rs199983221 and rs769519031 suggested reduced hydrophobicity due to Ile 4Thr and Ile223Ser resulting in decreased hydrophobic interactions. In contrast, on modelling rs778184510, the mutant protein had a higher hydrophobicity than the wild type. Conclusions: Our study reports that three nsSNPs (D357A, I223S, I4T) are the most damaging mutations of the SIRT1 gene. Mutations may result in altered protein structure and functions. Such altered protein may be the basis for various disorders. Our findings may be a crucial guide in establishing the pathogenesis of various disorders.

UGT2B7 gene polymorphism and linkage disequilibrium in pediatric epileptic patients and their influence on sodium valproate monotherapy: A cohort study.

Background: Uridine 5'-diphospho glucuronosyl transferase (UGT) is the main enzyme responsible for the glucuronide conjugation, the principal metabolic pathway of sodium valproate. The objective of the study was to explore if there was an association between the UGT2B7 genetic polymorphism and clinical efficacy and safety in paediatric epileptic patients on sodium valproate monotherapy. Methods and materials: The cohort study included 100 pediatric epileptic patients aged 2-18 years who had been on sodium valproate monotherapy for at least 1 month. PCR-RFLP was carried out to assess the genetic polymorphism patterns of UGT2B7 (C161T, A268G, G211T). Based on the extent of seizure control throughout the 1-year follow-up, clinical outcome was assessed in terms of responders and non-responders. Hepatic, renal, and other lab parameters were assayed to determine safety. The SNPstat web software was used to calculate linkage disequilibrium. Results: Out of 100 patients, CC (38%), CT (43%), TT (19%) pattern was observed in UGT2B7 (C161T) gene, AA (15%), AG (39%), GG (46%) in (A268G) gene and GG (80%), GT (18%), TT (02%) in (G211T) gene. There was no statistical difference in clinical outcome with distinct UGT2B7 genetic polymorphism patterns, according to the findings. With low D' and R2 values, linkage disequilibrium between alleles was statistically insignificant. However, the associations of C161T and G211T with treatment response were significant (p = 0.014) in determining treatment response. Conclusion: Our findings show that the genetic variation of UGT2B7 had no bearing on the clinical outcome of epilepsy. Gene interactions, on the other hand, had an impact on treatment response.

Association of Leptin and Leptin receptor Gene polymorphisms with Insulin resistance in pregnant women: A cross-sectional study.

Introduction: Leptin, along with its receptor, are linked with mechanisms affecting a diverse array of pregnancy-specific pathologies that include gestational diabetes and intrauterine growth restriction. The goal of the study was to examine if there was a link between the leptin (LEP)/leptin receptor (LEPR) gene polymorphism and insulin resistance in pregnant women, and to determine the extent to which the leptin gene polymorphism could cause insulin resistance.. Methods: 208 pregnant women participated in this cross-sectional study of which 74 were insulin resistant cases and 134 were insulin sensitive controls. The study was carried out from December 2018 to December 2020 at a charitable hospital in Mangalore, Karnataka, India. Genotyping of leptin and its receptor gene were carried out using the Polymerase Chain Reaction- Restriction fragment Length Polymorphism (PCR-RFLP) method. Serum levels of leptin, insulin, and C peptide were assayed using Enzyme Linked Immuno Sorbent Assay (ELISA). Statistical analysis was carried out using SPSS 23. Results: Insignificant association was observed between leptin receptor gene polymorphisms and insulin resistance, and leptin gene and insulin resistant women. There was no significant difference in the serum leptin levels among the cases and control (61.62±29.23 and 59.88±22.25). However, fasting blood sugar, insulin, C peptide, Triglycerides (TG), and very low-density Lipoprotein (VLDL) levels were significantly higher in cases as compared to controls (p=0.0068, p<0.0001, p<0.0001 and 0.01 respectively). Homeostatic Model Assessment for Insulin Resistance (HOMA IR) was greater in subjects with homozygous dominant, 'GG' of LEPR (p=0.0409) and hyperinsulinemia (p=0.023) as compared to other genotypes. However, hyperglycaemia was observed in subjects with homozygous dominant, 'AA' of leptin gene (p=0.0173). Conclusion: No significant association was found between leptin and leptin receptor gene polymorphisms with insulin resistance in pregnancy. However, genotyping of these genes may be useful in predicting insulin resistance and gestational diabetes in pregnancy.

Association of paraoxonase 1 activity and insulin resistance models in type 2 diabetes mellitus: Cross-sectional study.

BACKGROUND: Diabetes mellitus is a metabolic disorder characterized by hyperglycemia due to defects in insulin secretion, insulin action, or both. Chronic hyperglycemia induces reactive oxygen species and increases oxidative stress. Human serum paraoxonase-1 (PON-1) is an enzyme synthesized in the liver, and it is an antioxidant enzyme with a beneficial role in fighting oxidative stress. The objective of the study was to compare PON-1 activity in type 2 diabetes mellitus (T2DM) and nondiabetics, as well as to find the association between PON-1 activity and different insulin resistance (IR) models in diabetics. METHODS: The cross-sectional study recruited 100 diabetic and 100 age and gender-matched controls. Fasting blood glucose, insulin, and C-peptide, were assayed. PON-1 activity was measured by the spectrophotometric method. Various insulin resistance models based on insulin and C-peptide were constructed using appropriate formulae. Receiver operating characteristic was constructed to find if PON-1 can be a good marker for diabetes. RESULTS: PON-1 activity was found to be significantly higher (p < 0.0001) in diabetics compared to controls. Highly significant hyperinsulinemia (p < 0.0001) was noted in diabetics. C-peptide levels were significantly lower in cases (p = 0.0215) as compared to controls. Homeostasis model assessment (HOMA)-IR C was insignificantly higher in cases. HOMA B cell, HOMA 1% B cell, and C-peptide-based IR (CIR) were significantly lower in cases (p < 0.0001 and p = 0.002), respectively, as compared to controls. An odds ratio of 3.15 was obtained, which suggests that the risk of T2DM is 3 times higher in subjects with elevated PON-1 levels. Chi-square showed a significant association (p = 0.0001) between DM and PON-1 levels; the chi-square statistic value (with Yates correction) was 14.49. Correlation data showed that PON-1 activity had a significant negative correlation with quantitative insulin sensitivity check index (r = -0.265, p = 0.019). A significant negative correlation (r = -0.22, p = 0.016) was also seen between PON-1 and CIR (HOMA-IR C). There was no significant correlation seen between PON-1 and other IR models. CONCLUSION: It can be concluded from our study that PON-1 activity is elevated in T2DM patients, which can be a beneficial marker.

Association of insulin resistance and leptin receptor gene polymorphism in type 2 diabetes mellitus.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a chronic disease that is characterized by impaired glucose metabolism and insulin resistance. The objectives of the study were to evaluate the pattern of leptin receptor gene polymorphism Gln223Arg in T2DM and to identify its association with the serum leptin and insulin levels as well as with insulin resistance in diabetes. METHODS: In this cross-sectional study, genotyping of leptin receptor was done for Gln223Arg alleles by PCR-restriction fragment length polymorphism in 39 patients with type 2 diabetes. Serum leptin and insulin levels were assayed using enzyme linked sorbent assay in 39 cases and 45 nondiabetic controls. Insulin resistance was calculated by the homeostasis model assessment of insulin resistance (HOMA-IR) formula. Statistical analysis was performed with Graph pad Instat version 3. RESULTS: Hardy-Weinberg Equilibrium for the leptin receptor (LEPR) gene variants showed that alleles were in equilibrium. Leptin levels were insignificantly low in patients with diabetes compared to those in controls. Women in the control group showed significantly higher leptin levels (p < 0.05) compared with men. There was a significant difference in the serum insulin levels and insulin resistance (HOMA-IR) among patients with different genotypes (p = 0.04 and p = 0.0378, respectively). CONCLUSION: Leptin receptor gene polymorphism affected glucose metabolism by altering insulin resistance and pancreatic beta cells. Thus, single-nucleotide polymorphism of LEPR may affect the pathogenesis of T2DM.

UGT1A6 and UGT2B7 Gene Polymorphism and its Effect in Pediatric Epileptic Patients on Sodium Valproate Monotherapy.

OBJECTIVES: To evaluate the pattern of UGT1A6 and UGT2B7 gene polymorphism in pediatric epileptic patients and to compare the sodium valproate concentration in different patterns of UGT gene polymorphism. METHODS: In this cross-sectional study, 99 pediatric epileptic patients aged 2-18 y receiving Sodium valproate monotherapy for the past one month were included from JusticeK S Hegde Charitable hospital, Mangalore after obtaining informed consent. Genetic polymorphism patterns were evaluated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Trough level serum valproate concentration was estimated by high-performance liquid chromatography (HPLC). Sodium valproate concentration in different UGT genotypes was compared by Analysis of Variance (ANOVA). P value <0.05 was considered significant. RESULTS: In the present study population, the predominant mutant allele pattern was observed in UGT1A6 (T19G, A541G, A552C) gene. In UGT2B7 (A268G, C161T) showed predominant mutant allele pattern while (G211T) showed predominant wild type. Mean steady-state sodium valproate concentration was 105.40 ± 49.9 µg/ml and adjusted sodium valproate concentration was 5.5 ± 3.2 mg/kg/L. It was found that there was no statistical difference in sodium valproate concentration in different UGT1A6 and UGT2B7 gene polymorphism. CONCLUSION: The present study concluded that though there was a difference in pattern of gene polymorphism with concerning UGT1A6 and UGT2B7, however, it has not contributed to variation in serum concentration of sodium valproate in the present study population.

Association of Diabetic Nephropathy and Liver Disorders.

INTRODUCTION: Liver disorder is known to be a risk factor for Diabetes Mellitus (DM) and diabetic patients are at risk of developing liver disorders. Association of liver and renal disease is less explored in the field of research; hence, we conducted a retrospective study on this. AIM: To compare the renal and liver profiles of type II DM patients compared to healthy controls and find the association between the two profiles in diabetics. MATERIALS AND METHODS: The renal and liver profiles of 68 type II DM patients and 58 controls were compared. Estimated Glomerular Filtration Rate (GFR) (eGFR) was calculated using Modification of Diet in Renal Disease (MDRD) formula and was taken as a tool to grade different stages of diabetic nephropathy. Comparison of liver profiles between different stages of diabetic nephropathy was done. Correlations and associations were studied between eGFR and liver enzymes and Bilirubin. RESULTS: A significant elevation in Total Bilirubin (TB) (p< 0.15), Direct Bilirubin (DB) (p< 0.0035), Aspartate Amino Transferase (AST) and Alanine Amino Transferase (ALT) (p<0.0001) levels in diabetics was noted. An elevated eGFR and a significant correlation between eGFR and liver enzymes were observed. A significant association between liver and renal disease has been obtained in diabetics (p=0.0136). CONCLUSION: Significantly, high liver function tests and low eGFR were observed in type II diabetics. A significant positive correlation between liver enzymes (AST and ALT) and eGFR suggest a possible association between liver and kidney functions in DM.

Antioxidant activity and lipid peroxidation in preeclampsia.

BACKGROUND: Epidemiologic studies demonstrate a relation between preeclampsia and an increased risk of future maternal coronary heart disease. The pathophysiology of the underlying mechanism is unknown. Disorders of lipoprotein metabolism may contribute to endothelial dysfunction. Oxidative stress and decreased antioxidant defense enhances free radical-mediated membrane lipid peroxidation and possibly vascular endothelial damage. The aim of this study was to elucidate the possible relation between lipidemic status, lipid peroxidation and albumin with total antioxidant activity (AOA) that may contribute to atherogenicity in preeclamptic women. METHODS: Twenty-five women with preeclampsia and 25 normal pregnant women who were matched for maternal and gestational age were selected for the study. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), atherogenic index (AI), malondialdehyde (MDA), a marker of lipid peroxidation, AOA and albumin levels were measured. RESULTS: MDA, TC and AI were significantly elevated (p < 0.001), and HDL-C, AOA and albumin levels were significantly decreased (p < 0.001) in preeclamptic patients compared to the control group. CONCLUSION: We conclude that hypercholesterolemia leads to excessive lipid peroxidation. Coexistent diminution in antioxidant activity leads to an imbalance between prooxidants and antioxidants, resulting in oxidative stress. Oxidative stress and elevated AI may contribute to atherogenicity in preeclampsia.