Association of genetic polymorphism of PC-1 gene (rs1044498 Lys121Gln) with insulin-resistant type 2 diabetes mellitus in Punjabi Population of Pakistan

Current Studies on Molecular Mechanisms of Insulin Resistance

Diabetes is a metabolic disease that raises the risk of microvascular and neurological disorders. Insensitivity to insulin is a characteristic of type II diabetes, which accounts for 85-90 percent of all diabetic patients. The fundamental molecular factor of insulin resistance may be impaired cell signal transduction mediated by the insulin receptor (IR). Several cell-signaling proteins, including IR, insulin receptor substrate (IRS), and phosphatidylinositol 3-kinase (PI3K), have been recognized as being important in the impaired insulin signaling pathway since they are associated with a large number of proteins that are strictly regulated and interact with other signaling pathways. Many studies have found a correlation between IR alternative splicing, IRS gene polymorphism, the complicated regulatory function of IRS serine/threonine phosphorylation, and the negative regulatory role of p85 in insulin resistance and diabetes mellitus. This review brings up-to-date knowledge of the roles of signaling proteins in insulin resistance in order to aid in the discovery of prospective targets for insulin resistance treatment.

A review on interplay between obesity, lipoprotein profile and nutrigenetics with selected candidate marker genes of type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus, a rapidly growing epidemic, and its frequently related complications demand global attention. The two factors commonly attributed to the epidemic are genetic factors and environmental factors. Studies indicate that the genetic makeup at an individual level and the environmental aspects influence the occurrence of the disease. However, there is insufficiency in understanding the mechanisms through which the gene mutations and environmental components individually lead to T2DM. Also, discrepancies have often been noted in the association of gene variants and type 2 diabetes when the gene factor is examined as a sole attribute to the disease.

STUDY

In this review initially, we have focused on the proposed ways through which CAPN10, FABP2, GLUT2, TCF7L2, and ENPP1 variants lead to T2DM along with the inconsistencies observed in the gene-disease association. The article also emphasizes on obesity, lipoprotein profile, and nutrition as environmental factors and how they lead to T2DM. Finally, the main objective is explored, the environment-gene-disease association i.e. the influence of each environmental factor on the aforementioned specific gene-T2DM relationship to understand if the disease-causing capability of the gene variants is exacerbated by environmental influences.

CONCLUSION

We found that environmental factors may influence the gene-disease relationship. Reciprocally, the genetic factors may alter the environment-disease relationship. To precisely conclude that the two factors act synergistically to lead to T2DM, more attention has to be paid to the combined influence of the genetic variants and environmental factors on T2DM occurrence instead of studying the influence of the factors separately.

Associations of transcription factor 7-Like 2 (TCF7L2) gene polymorphism in patients of type 2 diabetes mellitus from Khyber Pakhtunkhwa population of Pakistan

Background

Type 2 diabetes mellitus (T2DM) is the most prevalent component of metabolic syndrome. Environmental factors and various complex genes like transcription factor 7-like 2 (TCF7L2) gene have involved in the disease development.

Objective

To determine TCF7L2 genetic association (rs7903146C/T and rs12255372G/T) in T2DM patients of Khyber Pakhtunkhwa population of Pakistan.

Subjects and methods

This study comprised of 176 subjects including 118 T2DM patients and 58 healthy controls. Genomic DNA was extracted and genotype of common variants (rs7903146 C/T and rs12255372 G/T) was carried out by amplification-refractory mutation system (ARMS)-PCR of sequence specific oligonucleotides.

Results

The distribution of genotype of TCF7L2 SNPs (rs7903146 C/T and rs12255372 G/T) was significantly associated with T2DM as compared to the controls (p <0.0001). The genetic models of the rs7903146 (C/T) and rs12255372 (G/T) SNPs were significantly associated between cases and controls (p <0.0001). On the other hand, the significant association was observed between the two SNPs and different biochemical parameters like serum fasting glucose, lipid profile, creatinine and blood HbA1c levels (p <0.05).

Conclusion

It is concluded that the SNPs of the TCF7L2 gene are significantly associated with T2DM disease susceptibility in the population of Khyber Pakhtunkhwa of Pakistan.

A Polymorphism in the Gene Encoding the Insulin Receptor Binding Protein ENPP-1 Is Associated with Decreased Glomerular Filtration Rate in an Under-Investigated Indigenous African Population

INTRODUCTION

The C allele of the ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP-1) rs1044498 polymorphism has previously been associated with increased binding of ENPP-1 to the insulin receptor (IR), resulting in decreased IR signalling and enhanced insulin resistance. It has also been associated with reduced kidney function in participants with diabetes of predominantly European and Asian descent. The association of this polymorphism with kidney disease in healthy Black South African participants has yet to be ascertained.

OBJECTIVE

This study, therefore, aimed to determine whether the K121Q polymorphism is associated with estimated glomerular filtration rate (eGFR) in a Black South African cohort.

METHODS

Black South African participants (n = 348) from an existing cohort with known eGFR levels were genotyped for the K121Q polymorphism using PCR-RFLP and assessed for any statistical association between genotype and kidney function.

RESULTS

Individuals with the A allele had significantly lower eGFR levels than individuals with the CC genotype (86.52 ± 18.95 vs. 93.29 ± 23.55 mL/min; p = 0.022). The association of the A allele with lower eGFR levels remained after controlling for sex, blood pressure, insulin resistance, age, smoking, thyroid-stimulating hormone, insulin-like growth factor-1, and BMI (R2 = 0.030, p < 0.001).

CONCLUSION

The rs1044498 A allele was significantly associated with lower eGFR levels in a cohort of apparently healthy Black South Africans, through an unknown mechanism that was independent of insulin resistance. It is possible that the rs1044498 polymorphism affects kidney function by altering the role of ENPP-1 in endothelial wound healing, podocyte signalling, or oxidative stress. Thus, the presence of this polymorphism may predispose individuals to a greater risk of CKD even in the absence of diabetes.

Ultra-performance liquid chromatography-mass spectrometry-based metabolomics reveals Huangqiliuyi decoction attenuates abnormal metabolism as a novel therapeutic opportunity for type 2 diabetes

Background: As a typical chronic metabolic disease, type 2 diabetes mellitus causes a heavy health-care burden to society. In this study, we applied the metabolomics strategy to explore the potential molecular mechanism of the Huangqiliuyi decoction (HQLYD) for type-2 diabetes (T2D). Ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) combined with pattern recognition methods was utilized to select specific metabolites closely associated with HQLYD. Biomarker pathway analysis and biological network were utilized to uncover the therapeutic effect and action mechanism related to HQLYD. A total of twenty-five biomarkers were identified in the animal model, in which sixteen biomarkers are associated with HQLYD treatment for T2D. They attenuated the abnormalities of metabolic pathways such as phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, and the citrate cycle. HQLYD also significantly elevated the serum FINS and SOD, GSP-x level in the liver and kidney, and reduced the serum TC, TG, HDL, LDL, urea, Scr, AST, ALT, FBG, IRS, MDA, and CAT level. We found that the therapeutic mechanism of HQLYD against T2D affected amino acid metabolism, glucose metabolism and lipid metabolism. Metabolomics revealed that the Huangqiliuyi decoction attenuates abnormal metabolism as a novel therapeutic opportunity for type 2 diabetes.

Association of genetic polymorphism of PC-1 gene (rs1044498 Lys121Gln) with insulin-resistant type 2 diabetes mellitus in Punjabi Population of Pakistan

BACKGROUND

Insulin resistance (IR), known to reduce the response to insulin action, develops with obesity leading to type 2 diabetes mellitus (T2DM). The PC-1 gene has been associated with dyslipidemia, polycystic ovarian disease and T2DM in different regions of the world. The objective of the present study was to investigate the genetic association of PC-1 rs1044498 polymorphism with insulin resistance in type 2 diabetes in the Punjabi population of Pakistan.

METHODS

This study was carried out on 161 healthy controls and 161 patients of T2DM with insulin resistance. Whole blood was collected for DNA extraction and molecular studies. PCR-RFLP with AvaII was performed to determine the genotype in cases and controls. Chi-square and Hardy Weinberg analyses were carried out. Statistical analysis was performed by SPSS software.

RESULTS

The demographic data of cases and controls showed significant differences for different parameters like glucose, insulin, Homeostatic model assessment-insulin resistance (HOMA-IR) and lipid profiles (p < 0.000). Different statistical models revealed that all the dominant models were found associated in between alleles for disease risk (p < 0.001) while no association of PC-1 rs1044498 (K121Q) polymorphism was found with insulin-resistant parameters in T2DM cases.

CONCLUSION

Overall, the results indicate that the K121Q polymorphism was not found associated with insulin resistance in type 2 diabetes in a Pakistani Punjabi population. This is the first-ever report about the genotype of PC-1 gene in this population.