Renalase gene Glu37Asp polymorphism affects susceptibility to diabetic retinopathy in type 2 diabetes mellitus

Association of resistin rs1862513, rs10401670 and rs3745367 polymorphisms with resistin level and insulin resistance in an Iranian type 2 diabetic population

Objectives

The study investigates the association of single nucleotide polymorphisms (SNP) in resistin gene (RETN) with resistin level, insulin resistance, and the risk of type 2 diabetes in an early diagnosed type 2 diabetic population of Iran.

Methods

The total of 80 healthy subjects and 80 individuals diagnosed with type 2 diabetes. To ascertain the genotypes of rs1862513 and rs3745367, we performed the polymerase chain reaction with restriction fragment length polymorphism (PCR-RFLP) technique. The genotyping of resistin rs10401670 was conducted a Tetra-arms amplification system. Resistin and insulin levels were also measured by the ELISA method. Statistical analyses were performed by SPSS software.

Results

Resistin level was increased significantly in patients with type 2 diabetes; a significant difference was seen in biochemical parameters between diabetic and non-diabetic group except high-density lipoprotein cholesterol (HDL-C), low density lipoprotein (LDL-C), and insulin. We did not find statistically a significant association between type 2 diabetes mellitus [T2DM] and resistin gene at SNP. However, rs3745367 exhibit a significant association with resistin level among individuals with diabetes. The serum resistin level exhibited a positive association level with body mass index, FPG and insulin resistance. Additionally, anegative correlation between resistin levels and age, as well as HDL-C was also revealed (P-value < 0.05).

Conclusions

No significant association was observed between the rs1862513, rs10401670, and rs3745367 polymorphisms, with the susceptibility to type 2 diabetes. The serum resistin levels was positively correlated body with mass index, FPG and insulin resistance, but negatively correlated with HDL-C.

KLK8: charting new territories in left ventricular hypertrophy biomarker research

OBJECTIVE

This study investigates the diagnostic potential of serum Kallikrein-related peptidase 8 (KLK8) in detecting left ventricular hypertrophy (LVH).

METHODS

A total of 62 hypertensive patients with LVH, 60 without LVH, and 60 healthy controls were analyzed. LVH was defined by echocardiography using LVMI thresholds (>95 g/m2 for females, >115 g/m2 for males). Serum KLK8 levels were measured via ELISA, and receiver operating characteristic (ROC) curve analysis assessed its diagnostic performance.

RESULTS

KLK8 levels were significantly higher in hypertensive patients with LVH (8.59 ± 1.59 ng/mL) than in those without LVH (5.80 ± 1.35 ng/mL) and healthy controls (3.68 ± 0.82 ng/mL). KLK8 positively correlated with blood pressure and cardiac structural parameters, including IVST, LVPWT, and LVEDD. ROC analysis revealed high sensitivity and specificity, indicating KLK8's potential as a biomarker for early LVH detection in hypertension.

CONCLUSION

In hypertensive patients, KLK8 demonstrates good diagnostic value in predicting LVH.

Renalase rs2296545 variant improve hypertension susceptibility by modifying binding affinity to catecholamines in obstructive sleep apnea

Obstructive sleep apnea (OSA), a condition often linked with hypertension, has an undefined relationship with renalase, a protein known for regulating blood pressure. This study aimed to investigate the relationship between serum renalase levels as well as renalase functional single nucleotide polymorphism (SNP) rs2296545 variant and hypertension in a Han Chinese OSA population. 126 subjects underwent serum renalase detection, with linear regression being performed to evaluate the relationship between serum renalase levels and OSA-related traits. Additional 4275 subjects were obtained rs2296545 genotype information by SNP microarray. And binary logistic regression was used to assess the effect of rs2296545 on hypertension risk. Molecular dynamics simulation and molecular docking were utilized to access the protein structures and the interplay between protein and catecholamines of wild-type and rs2296545 mutant renalase. The results showed that serum renalase levels were significantly higher in the severe OSA group. Further analysis showed renalase levels were positively correlated with blood pressure in the non-OSA group and negatively correlated in the severe OSA group. For rs2296545 polymorphism analysis, the hypertension risk significantly increased for the recessive model CC/GG + CG (OR = 1.211, 95% CI: 1.025-1.431) and the additive model CC/CG (OR = 1.223, 95% CI: 1.025-1.458) in the severe OSA. The rs2296545 polymorphism affected protein structure, and led to increase binding free energy, weakening interactions between renalase and catecholamines. In conclusion, serum renalase levels had independent association with blood pressure. And rs2296545 polymorphism may influence on susceptibility to hypertension by altering protein ability to bind to catecholamines, which might contribute to the intervention of hypertension in the OSA population.

The Role of Genetic Polymorphisms in Diabetic Retinopathy: Narrative Review

Diabetic retinopathy (DR) is renowned as a leading cause of visual loss in working-age populations with its etiopathology influenced by the disturbance of biochemical metabolic pathways and genetic factors, including gene polymorphism. Metabolic pathways considered to have an impact on the development of the disease, as well as genes and polymorphisms that can affect the gene expression, modify the quantity and quality of the encoded product (protein), and significantly alter the metabolic pathway and its control, and thus cause changes in the functioning of metabolic pathways. In this article, the screening of chromosomes and the most important genes involved in the etiology of diabetic retinopathy is presented. The common databases with manuscripts published from January 2000 to June 2023 have been taken into consideration and chosen. This article indicates the role of specific genes in the development of diabetic retinopathy, as well as polymorphic changes within the indicated genes that may have an impact on exacerbating the symptoms of the disease. The collected data will allow for a broader look at the disease and help to select candidate genes that can become markers of the disease.

Molecular Role of Asn680Ser and Asp37Glu Missense Variants in Saudi Women with Female Infertility and Polycystic Ovarian Syndrome

Female infertility (FI) is a global health issue. Polycystic ovary syndrome (PCOS) is a common cause of FI. The renalase gene (RNLS) is associated with FI and other human diseases. Based on the documented missense variants, rs6166 and rs2296545 single-nucleotide polymorphisms (SNPs) were not identified in Saudi women with FI and PCOS. This study aimed to investigate the molecular role of the two SNPs in Saudi women with FI and PCOS. In this cross-sectional study, 96 healthy controls, 96 women with FI, and 96 women with PCOS were recruited. DNA was isolated, and polymerase chain reactions and Sanger sequencing analysis were performed using rs6166 and rs2296545 SNPs. The data obtained from the three groups were used to perform statistical analyses based on genotype, allele frequencies, regression models, and ANOVA analysis. Both rs6166 and rs2296545 had no role in FI or PCOS in Saudi women. A predicted reason for non-association in Saudi women could be the role of elderly women in the controls compared with women with FI and PCOS. Moreover, age, weight, and body mass index were higher in the control group than the FI and PCOS groups. In conclusion, rs6166 and rs2296545 SNPs were not associated with FI or PCOS in Saudi women.

Leu72Met Polymorphism in Ghrelin Gene: A Potential Risk Factor for Hypertension in Type 2 Diabetes Patients

OBJECTIVE

Ghrelin (GHRL) is known to be engaged in metabolic and cardiovascular processes. There is evidence suggesting its involvement in the regulation of blood pressure and hypertension. The purpose of this preliminary case-control study was to determine the involvement of the Leu72Met (rs696217) polymorphism in the GHRL gene in type 2 diabetes (T2DM).

METHODS

The Leu72Met polymorphism was genotyped in 820 individuals with T2DM and 400 healthy subjects by the PCR-RFLP technique. The polymorphism distribution was first compared in those withT2DM and controls, then in subgroups of participants representing different clinical phenotypes.

RESULTS

No significant association was identified between Leu72Met and T2DM. The distribution of polymorphism was analyzed in subgroups of individuals with different clinical phenotypes (hypertension, diabetic nephropathy, obesity). In this analysis, rs696217 was associated with hypertension. The presence of T allele was associated with higher risk of hypertension (OR = 2.50, 95% CI 1.68-3.73, p < 0.001). When adjusted for age, gender and BMI, the association was still significant (OR = 2.62, 95% CI 1.83-3.96, p < 0.001). A post hoc power calculations based on a minor allele frequency revealed the power of 97% for comparison between HY+ and HY- subgroups.

CONCLUSION

This is the first study demonstrating that the ghrelin Leu72Met SNP is associated with hypertension in Caucasians with T2DM. If confirmed in larger studies in different populations, it may be a novel potential risk factor for hypertension in individuals withT2DM.

Association of Long Non-Coding RNA Growth Arrest-Specific 5 Genetic Variants with Diabetic Retinopathy

The aim of this work was to appraise the potential associations of single nucleotide polymorphisms (SNPs) of long non-coding RNA growth arrest-specific 5 (GAS5) with diabetic retinopathy (DR) in a diabetes mellitus (DM) population. Two loci of the GAS5 SNPs (rs55829688 and rs145204276) were genotyped via TaqMan allelic discrimination in 449 non-DR patients and 273 DR subjects. The SNP rs145204276 Del/Del showed a significantly higher distribution in the DR group compared to the non-DR group (AOR: 2.487, 95% CI: 1.424–4.344, p = 0.001). During subgroup analyses, the non-proliferative diabetic retinopathy (NPDR) subgroup demonstrated a significantly higher ratio of the SNP rs145204276 Del/Del (AOR: 2.917, 95% CI: 1.574–5.406, p = 0.001) and Ins/Del + Del/Del (AOR: 1.242, 95% CI: 1.016–1.519, p = 0.034) compared to the non-DR population, while the proliferative diabetic retinopathy (PDR) subgroup did not reveal significant differences in either SNP rs145204276 or rs55829688 distributions compared to the non-DR group. Furthermore, patients with a GAS5 SNP rs145204276 Del/Del showed a significantly shorter DM duration than the wild type (Ins/Ins) (p = 0.021). In conclusion, our findings demonstrate that the GAS5 SNP rs145204276 Del/Del variant is associated with an increased susceptibility to DR in DM patients, particularly in those patients with NPDR.