Gene-environment interaction in chronic kidney disease among people with type 2 diabetes from The Malaysian Cohort project: a case-control study

Matrix Gla Protein and Nitric Oxide Synthase-3 Genetic Variants in Chronic Kidney Disease and Their Relation with Cardiovascular Risk

Background

Chronic kidney disease (CKD) is defined by gradual deterioration of renal parenchyma and decline of functioning nephrons. The risk of cardiovascular events is drastically increased in patients with CKD. This complicated link of CKD and cardiovascular disease (CVD) is not well understood till date.

Objective

We aim to study the influence of genetic variants of matrix Gla protein (MGP) gene rs1800801, rs1800802, and rs4236 and nitric oxide synthase-3 (NOS3) gene rs1799983 and rs2070744 on the risk of CKD and its associated cardiovascular comorbidity in South Indian Tamils.

Methods

One hundred and eighty-five CKD patients and 185 controls were recruited in this research. Flow-mediated dilatation (FMD) of brachial artery was measured ultrasonically. Circulating levels of MGP and nitric oxide (NO) were measured by ELISA. Genotyping was done by real-time PCR.

Results

We observed a significant difference in the distribution of TT and CT genotypes of NOS3 (rs2070744), indicating an increase in the risk of CKD. NO level was significantly decreased in CKD cases than controls. We also found a significant difference in the distribution of TTA and CCG haplotypes of MGP polymorphisms (1-rs4236; 2-rs1800801; 3-rs1800802) between the groups, indicating an increase in the risk of CKD. CT genotype of MGP (rs4236) and CT genotype of NOS3 (rs2070744) variants were found to be associated with decreased FMD, indicating endothelial dysfunction, the harbinger of CVD.

Conclusion

We conclude that genetic variants of MGP and NOS3 enhance the risk of CKD and its associated cardiovascular comorbidity in South Indian Tamils.

Association between nitric oxide synthase (NOS3) gene polymorphisms and diabetic nephropathy: An updated meta-analysis

Polymorphisms located within NOS3 gene have been investigated as susceptibility variants for diabetic nephropathy (DN) in type 2 diabetes mellitus (T2DM) in a large number of studies. However, these previous articles yielded inconsistent results and we aimed at elucidating the impact of NOS3 variants on DN risk in T2DM by conducting an updated systematic data synthesis. A total of 36 studies (12,807 participants) were selected for qualitative data synthesis, while 33 records with 11,649 subjects were included in the meta-analysis. The pooled analysis demonstrated the association of minor alleles of rs2070744 and rs1799983 with an increased susceptibility to DN (P < 0.001 and P = 0.015 for allelic model, respectively). For both of these variants, a significant effect of subgrouping according to ethnicity was found. Rs869109213 displayed an association with DN susceptibility, with pooled effect measures indicating a predisposing effect of the minor allele a (Prec = 0.002, ORrec = 1.960, 95%CI 1.288-2.983; Paavs. bb = 0.001, ORaavs. bb = 2.014, 95%CI 1.316-3.083). These findings support the effects of NOS3 variants on the risk of developing DN in T2DM.

Recent Progress in Genetics and Epigenetics Research on Diabetic Nephropathy in Malaysia

Diabetic nephropathy is a multifactorial disease. Gene susceptibility, as well as environmental exposure, plays an important role in disease progression. Malaysia is reported to be among the world's second-fastest-growing rates of kidney failure. Diabetic nephropathy has become the main cause of end-stage renal disease in Malaysia. This article is aimed at reviewing genetic studies conducted among diabetic nephropathy patients in the Malaysian population. This review was conducted by searching PubMed, MEDLINE, and Google Scholar databases to identify all relevant papers published in English from March 2022 to April 2022, using the following keywords: diabetes, type 2 diabetes, diabetic nephropathy, diabetic kidney disease, and Malaysia. The case-control study among diabetic patients with and without diabetic nephropathy showed a significant association with diabetic nephropathy in CNDP1, NOS3, and MnSOD genes. In the ethnic subgroup analysis, significant differences for diabetic nephropathy in terms of diabetes duration (≥10 years) were observed for CCL2 rs3917887, CCR5 rs1799987, ELMO1 rs74130, and IL8 rs4073. The IL8 rs4073 was associated only with the Indians, while the CCR5 rs1799987 was associated with the Chinese. In Malays, SLC12A3 Arg913Gln polymorphism and ICAM1 K469E (A/G) polymorphism were found to be associated with diabetic nephropathy. Studies on gene-environment interactions have suggested significant genetic and environmental factors such as smoking, waist circumference, and sex for eNOS rs2070744, PPARGC1A rs8192678, KCNQ1 rs2237895, and KCNQ1 rs2283228 with kidney disease. The genetic variants' contributions differed across ethnic groups. Therefore, a study to validate the genetic variants that are found to be associated with different ethnicities in Malaysia may be important in future studies.

Knowledge of chronic kidney disease among undergraduate and postgraduate students in a public university in Klang Valley, Malaysia: A cross sectional study

The prevalence of chronic kidney disease (CKD) risk factors such as diabetes mellitus, hypertension, and obesity among the young Malaysians are increasing. Understanding the factors associated with CKD knowledge could assists healthcare providers to design health education programmes. There are scarce local studies on CKD knowledge and its associated factors among university students. This subpopulation comprises of young people with diverse background and characteristics. This study was aimed to assess the CKD knowledge and its associated factors among university students. A cross-sectional study was conducted among Universiti Kebangsaan Malaysia students from July 2020 to August 2020. A convenience sampling method was applied. All students were invited to complete an online survey using Google Forms that were sent to their email. The survey consisted of questions related to their sociodemographic, socioeconomics, university programme enrolled, medical history, lifestyle characteristics and CKD knowledge. The data were analysed using SPSS Statistics 26.0. Multiple logistic regression analysis was performed to identify the final associated factors after controlling for confounders. A total of 3074 students participated and 32.6% of them had below average CKD knowledge. Students of male gender, enrolment in undergraduate programmes and non-health-related faculties/institutes were more likely to have below average CKD knowledge. Students who are Chinese, from high monthly household income family and with family history of CKD were less likely to have below average CKD knowledge. Almost one-third of the students had below average CKD knowledge. The six associated factors with CKD knowledge were non-modifiable. Of the six factors, three were associated with students being more likely to have below average CKD knowledge; another three were associated with students being less likely to have below average CKD knowledge. Future health education programmes to enhance CKD knowledge should be designed focusing on students who are more likely to have below average CKD knowledge.