Association of A1538G and C2437T single nucleotide polymorphisms in heat shock protein-70 genes with diabetic nephropathy among South Indian population

Vascular Endothelial Growth Factor Single Nucleotide Polymorphism +405 G/C (rs2010963) is associated with Levels, Infection Severity, and Amputation among South Indian Diabetic Foot Ulcer Patients

Background

The regulation of vascular endothelial growth factor (VEGF) by genetic factors in T2DM and DFU still requires thorough investigation. Hence, the present study aimed to investigate the association of VEGF +405 G/C in DFU subjects and correlate it with its circulatory levels, infection severity, and amputation rate.

Materials and Methods

This study registered a total of 754 participants of which group I: healthy controls (n = 297), group II: T2DM subjects (n = 242), and group III: DFU subjects (n = 215). Genotyping and levels of rs2010963 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and ELISA, respectively.

Results

Results of the current study showed a clear decline in circulatory VEGF-A levels in DFU subjects. VEGF-A was decreased in DFU subjects with the mutant "CC" genotype. The mutant "CC" of VEGF +405G/C was also found to be more susceptible to ulcer grade (III and IV) and major amputations.

Conclusion

VEGF +405G/C SNP is associated with levels, infection severity, and amputation amongst South Indian DFU patients.

Diagnostic and Prognostic Risk Assessment of Heat Shock Protein HSPA1B rs2763979 Gene Variant in Asthma

Given the significant role the heat shock protein Hsp70 plays in modulating cellular homeostasis in several chronic inflammatory disorders, the genetic variation of the inducible HSP70 (HSPA1B) gene may impact protein expression and disease phenotype. The HSPA1B rs2763979 variant has been associated with multiple inflammatory scenarios, but no previous studies have explored its association with asthma. In this sense, this cross-sectional study enrolled 90 children with asthma and 218 age-/sex-matched healthy volunteers for rs2763979 variant genotyping by TaqMan allelic discrimination analysis. The results were investigated under several genetic models and associated with disease susceptibility and clinicolaboratory data. Overall analysis, including the 308 participants, revealed a higher C allele frequency among patients relative to controls (43.0% vs. 33%, p = 0.006). Furthermore, patients with the C variant initially had a higher risk of asthma under heterozygous (OR = 2.75, 95%CI = 1.46-5.18, p = 0.003), homozygous (OR = 3.35, 95%CI = 1.19-9.39, p = 0.008), dominant (OR = 2.83, 95%CI = 1.52-5.25, p < 0.001), and overdominant (OR = 2.12, 95%CI = 1.20-3.74, p = 0.008) models. However, after employing a 1:1 nearest propensity matching analysis, the studied variant showed only borderline significance with asthma under the dominant model in 71 matched cohorts. Interestingly, patients who carry the rs2763979 CC genotype showed favorable spirometric parameters in terms of better (mean ± SD) forced vital capacity (86.3 ± 7.4 vs. 77.7 ± 6.1 and 75.7 ± 7.2 for CT and TT, respectively, p = 0.021), forced expiratory volume in one second before bronchodilation (60.7 ± 12.9 vs. 54.9 ± 7.6 and 56.1 ± 7.5 for CT and TT, respectively, p = 0.021), and an improvement in peak expiratory flow rate after inhaled salbutamol bronchodilator (p = 0.044) relative to the counterpart genotypes. In conclusion, the HSPA1B rs2763979 variant might have prognostic utility as a genetic marker for asthma in our population. Further larger studies on different ethnicities are recommended to validate the results.

IL-6 and HSPA1A Gene Polymorphisms May Influence the Levels of the Inflammatory and Oxidative Stress Parameters and Their Response to a Chronic Swimming Training

The aim of the study was to evaluate whether the most common polymorphisms in the IL-6 and HSP70 genes affect the circulating heat shock protein 70 (HSP70), as well as inflammatory and prooxidant-antioxidant parameters in healthy men undergoing chronic endurance training. The subjects were randomly assigned to a 12-week swimming training (ST group) or control group (CON). Fasting blood samples were collected pre- and post-study period to assessment: superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, serum levels of lipid hydroperoxides (LHs), tumor necrosis factor α (TNFα), and HSP70. Subjects were genotyped for IL-6-174G/C, HSPA1A + 190 G/C and HSPA1B + 1538 A/G single nucleotide polymorphisms (SNPs) by real-time PCR. After a 12-week study period, a decrease in TNFα, HSP70, and GPx was observed in the ST group, but not the CON group. IL-6 SNP affected serum TNFα levels (main effect of genotype). Higher TNFα levels (pre- and post-study period) was observed in CC CON than in other IL-6 genotypes of CON and ST groups. However, a post-training decrease in TNFα was observed in both GG and CC IL-6 genotypes of ST group. In turn, only GG IL-6 genotype of the ST group was related to a post-training decrease in HSP70 (main time and genotype interaction). Moreover, pre- and post-training LHs were lower in GG than GC/CC HSPA1A genotypes of the ST group (main genotype effect). In conclusion, polymorphisms within the IL-6 and HSPA1A genes seem to affect baseline levels of some inflammatory parameters and prooxidant-antioxidant status and/or their changes after chronic swimming training. However, the results should be confirmed in a study with a larger sample size, one that includes individuals with sedentary lifestyles.

Screening of key genes associated with m6A methylation in diabetic nephropathy patients by CIBERSORT and weighted gene coexpression network analysis

Diabetic nephropathy (DN) is a common complication of diabetes. Due to its complex pathogenesis, there is no effective treatment. M6A is a newly discovered epigenetic mechanism that may be involved in the development of diabetic nephropathy. In this study, we analyzed differentially expressed genes (DEG) in the GEO database (GSE96804) and paid attention to genes with m6A methylation. 623 DEGs in glomerular tissue were identified by comparing diabetic nephropathy with normal. Correlation analysis with 21 genes involved in m6A modification showed that 492 genes were associated with m6A methylation. According to the CIBERSORT algorithm, the infiltration of M1 macrophages in DN patients was significantly higher than that in normal samples. Weighted gene coexpression network analysis (WGCNA) was used to screen for the modules most correlated with the clinical features of M1 macrophages. The genes in the selected modules and 492 m6A-related DEGs were intersected by a Venn diagram, and 43 key genes were obtained. GO and KEGG analyses showed that these genes were mainly related to the positive regulation of protein aggregation and the transforming growth factor β receptor signaling pathway. According to a literature review, among the top 10 genes, HSPA1A, HSPA1B, CHI3L1, TYRO3 and PTH1R are markers in diabetic nephropathy, and their abnormal expression is associated with renal hypertrophy, proteinuria and glomerulosclerosis. These findings may provide evidence for the diagnosis and treatment of diabetic nephropathy.

Association of Fetuin-A with Thr256Ser exon polymorphism of α2-Heremans Schmid Glycoprotein (AHSG) gene in type 2 diabetic patients with overt nephropathy

BACKGROUND

Circulatory Fetuin-A has been well reported to elevate the risk for Diabetic Nephropathy (DN) and is associated with many vascular complications. Compelling reports have well documented that the circulatory levels of Fetuin-A directly have an impact on its AHSG (α2- Heremans- Schmid Glycoprotein) gene single nucleotide polymorphisms (SNP). Thus, in this study among the South Indian T2DM population, we aim to explore the association of AHSG Thr256Ser (rs4918) SNP in subjects with DN and correlate with the circulatory levels of Fetuin-A at various stages of DN patients.

METHODS

A total of 975 subjects were recruited, such as Group-I, consisting of Controls (n = 300), Group-II, with normoalbuminuria (n = 300), Group-IIIa, with incipient microalbuminuria (n = 195), Group-IIIb, with persistent macroalbuminuria (n = 180)] and were subjected for genotyping using PCR-Restriction Fragment Length Polymorphism (RFLP). Circulatory Fetuin-A was measured using sandwich enzyme-linked immunosorbent assay (ELISA).

RESULTS

The 'G' allele of AHSG exon-7 (C/G) SNP is significantly concomitant and conferred significant risk for normoalbuminuria subjects. In the DN subjects, the 'G' allele showed the risk for persistent macroalbuminuria. A noticeable stepwise decrease was evidenced in the circulatory Fetuin-A among persistent macroalbuminuria over incipient microalbuminuria from normoalbuminuria. Further, the circulatory Fetuin-A was lowered in DN subjects with mutant GG genotype than the wild CC.

CONCLUSION

AHSG Thr256Ser (rs4918) SNP was associated with renal complications among South Indian T2DM subjects.

The association of heat shock protein genetic polymorphisms with age-related hearing impairment in Taiwan

BACKGROUND

Age-related hearing impairment (ARHI) is a major disability among the elderly population. Heat shock proteins (HSPs) were found to be associated with ARHI in animal studies. The aim of this study was to analyze the associations of single nucleotide polymorphisms (SNPs) of HSP genes with ARHI in an elderly population in Taiwan.

METHODS

Participants ≥65 years of age were recruited for audiometric tests and genetic analyses. The pure tone average (PTA) of the better hearing ear was calculated for ARHI evaluation. The associations of HSPA1L (rs2075800 and rs2227956), HSPA1A (rs1043618) and HSPA1B (rs2763979) with ARHI were analyzed in 146 ARHI-susceptible (cases) and 146 ARHI-resistant (controls) participants.

RESULTS

The "T" allele of HSPA1B rs2763979 showed a decreased risk of ARHI. The "TT" genotype of rs2763979 also showed a decreased risk of ARHI in the dominant hereditary model. For HSPA1L (rs2075800 and rs2227956) and HSPA1A (rs1043618), the haplotype "CAG" was related to a decreased risk of ARHI.

CONCLUSION

These findings suggest that HSP70 polymorphisms are associated with susceptibility to ARHI in the elderly population.

Association of polymorphism in heat shock protein 70 genes with type 2 diabetes in Bangladeshi population

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a chronic disorder of which stress is a major contributor. Under stressful condition, body synthesizes a family of molecular chaperone called Heat-shock proteins (HSPs). Current study assessed the frequency and association of HSP70-hom + 2,437 T/C polymorphism with T2DM risk among Bangladeshis.

METHODS

This polymorphism was selected through bioinformatics analyses and identified by PCR-RFLP method.

RESULTS

Bioinformatics analysis identified this SNP as missense mutation which could destabilize the final HSP product. Heterozygous mutant (CT) genotype was significantly associated with T2DM incidence among the studied populations (p = .015). Further analysis revealed a strong association with female patients (p = .002), while the male group showed no association (p = .958). Moreover, the C allele was significantly associated among all diabetic patients (p = .016) and particularly in the female patient group (p = .001). However, under stressful condition, males with CT genotype were at high risk for T2DM incidence whereas, females with CT genotype showed no significant association.

CONCLUSIONS

HSP70-hom + 2,437 T/C polymorphism was found to be significantly associated with T2DM incidence in the Bangladeshi population in both stress-dependent and independent manners.

The differential neuroprotection of HSP70-hom gene single nucleotide polymorphisms: In vitro (neuronal hypoxic injury model) and in vivo (rat MCAO model) studies

To investigate the effect of HSP70-hom+2437 single nucleotide polymorphisms (SNPs) on hypoxia and ischemia condition, we constructed the neuronal hypoxic injury model and the rat middle cerebral artery occlusion (MCAO) model to compare the inhibition rate of neurons and detect the infarct volume as well as the expression of related apoptotic proteins in order to explore the possible mechanisms. The neuroblastoma cells SHSY5Y were divided into the OE (transfected with the C allele) group, OEmu (transfected with the T allele) group and negative control (NC, transfected with the empty lentiviral vector CON195) group. Varying degrees of hypoxia were induced by deferoxamine (DFO). The inhibition rate of hypoxic neurons and the expression of related apoptotic proteins were detected in the three genotype groups. While in the rat MCAO model, we built five groups including the sham group, the blank control group (injected with physiological saline), the negative control group (injected with lentivirus and physiological saline), the C allele group and the T allele group (injected with lentivirus overexpressing C and T allele). The MCAO model operation was then underwent in all five groups, the infarct volume by TTC staining and the expression of related apoptotic proteins were detected after 24 h. The results in neuronal hypoxic injury model showed a significant difference in the inhibition rate between the three groups (P < 0.05), and the average inhibition rates for the OEmu, OE and NC groups were 13.2%, 19.2% and 23.3%, respectively. The inhibition rates also differed between lower and higher DFO concentrations (P < 0.05). Compared with the NC group, Bax decreased significantly in the OE and OEmu groups, whereas PI3K and HSPA1L (HSP70-hom) increased. However, the expression of Bax in the OEmu group decreased significantly more than in the OE group, whereas PI3K and HSPA1L levels showed no difference between the two groups. Corresponding with the results above, overexpressing HSP70-hom could reduce the infarct volume of ischemic injury by TTC staining in rat MCAO model and the T allele group also had less infarct volume than C allele group. Compared with the sham group, blank control group and negative control group, Bax decreased significantly in the C and T allele groups, while HSPA1L and p- AKT increased. Furthermore, the expression of Bax in the T allele group decreased significantly more than that in the C allele group, while there were no significant differences in HSPA1L and p-AKT levels between the two groups. Therefore, the overexpression of HSP70-hom+2437 could play a protective role in hypoxic neurons and ischemic brain tissue by upregulating the expression of HSPA1L and PI3K/p-AKT and downregulating the expression of BAX. The neuroprotective effect of the T allele was stronger than that of the C allele, which may be related to the strengthened downregulation of BAX.

Impact of XPF rs2276466 polymorphism on cancer susceptibility: a meta-analysis

Association between the xeroderma pigmentosum complementation group F (XPF)rs2276466 located in the excision repair cross complementation group 4 (ERCC4) gene and cancer susceptibility has been widely investigated. However, results thus far have remained controversial. A meta-analysis was performed to identify the impact of this polymorphism on cancer susceptibility. PubMed, Embase and Science-Web databases were searched systematically up to May 20, 2018, to obtain all the records evaluating the association between the rs2276466 polymorphism and the risk of all types of cancers. We used the odds ratio (OR) as a measure of effect, and pooled the data in a Mantel-Haenszel weighed random-effects meta-analysis to provide a summary estimate of the impact of this polymorphism on gastrointestinal cancer, neurogenic cancer and other cancers (breast cancer and SCCHN). All the analyses were carried out in STATA 14.1.11 case–control studies that consisted of 5730 cases and 6756 controls, were eventually included in our meta-analysis. The significant association was observed between the XPFrs2276466 polymorphism and neurogenic cancer susceptibility (recessive model: OR = 1.648, 95% CI = 1.294–2.098, P<0.001). Furthermore, no significant impact of this polymorphism was detected on decreased gastrointestinal cancer risk (dominant model: OR = 1.064, 95%CI = 0.961–1.177, P = 0.233). The rs2276466 polymorphism might play different roles in carcinogenesis of various cancer types. Current evidence did not suggest that this polymorphism was directly associated with gastrointestinal susceptibility. However, this polymorphism might contribute to increased neurogenic cancer risk. More preclinical and epidemiological studies are still imperative for further evaluation

Meta-analysis for assessing the healing process of ulcers among diabetic patients: Cases of HbA1c, lipid, S. Creatinine, Adiponectin, Cat D, HSP70, HSP47, 25-hydroxy vitamin D

BACKGROUND

The study aims to investigate the significance of predictors including HbA1c, Lipid, S. Creatinine, Adiponectin, Cat D, HSP70, HSP47, and 25-hydroxy vitamin D and to evaluate the rate of healing of ulcers among the diabetic foot patients.

METHODS

A retrospective method is used to quantitatively assess the role of HbA1c, Lipid, S. Creatinine, Adiponectin, Cat D, HSP70, HSP47, and 25-hydroxy vitamin D in the healing process of ulcer among diabetic patients. A total of 192 diabetic patients were included, who underwent ulcer healing diagnosis.

RESULTS

The results have shown a positive and significant correlation between Adiponectin and Cat D with group 2. The findings have shown higher prevalence of Cad D among patients with group 1, HSP70 among patients with group 2, HSP47 among patients with group 2, and 25-hydroxy vitamin D among patients with group 1.

CONCLUSION

The study concluded that insignificant predictors should be assessed more comprehensively to reveal its efficacy on healing of ulcers with different grades.

Heat Shock Protein 70 Gene Single Nucleotide Polymorphism and Diabetic Foot Ulcer. Is There Any Relationship?

Objective: The study aims to investigate the potential role of C2437T (Met493Thr) single nucleotide polymorphism (SNP) of the heat shock protein (HSP) 70 in diabetic foot ulcer patients. Methods: In this prospective cohort study, SNP of the HSP70 hom gene, also called HSPA1L, was studied among diabetic patients with an ulcer (Group A: n = 50), diabetic patients without an ulcer (Group B: n = 50), and healthy subjects (Group C: n = 50). Results: There was a higher frequency of T/T genotype in group A (76%) as compared to group B (44%) and group C (14%). Moreover, the frequency of T allele was 7.3% in group A, 5.5% in group B, and 3.9% in group C. C allele frequency was 2.6%, 4.4%, and 6.1% in group A, group B, and group C, respectively. In group A, the odds ratio and risk ratio were 19-fold and 5-fold, respectively, for the HSP70 hom T/T homozygous gene compared to B (OR 19.45; RR 5.42; X² 38.8, p < 0.0001). Moreover, 4-fold and 1.75-fold ratios have been compared with group C (OR 4.03; RR 1.72; X² 10.6, p < 0.001). No significant difference in genotype was observed in group B and group C. Conclusions: There is a significant and positive association of hspHSP70 hom polymorphism restricted to T allele in homozygous and heterozygous states among diabetic foot ulcer (DFU) patients.

BSMI single nucleotide polymorphism in vitamin D receptor gene is associated with decreased circulatory levels of serum 25-hydroxyvitamin D among micro and macrovascular complications of type 2 diabetes mellitus

Vitamin D Receptor (VDR) gene single nucleotide polymorphism (SNP) in the intron 8 is a well characterized SNP which has previously been linked to various diseases including Type 2 Diabetes Mellitus (T2DM). However, the association of this SNP with micro and macrovascular complications of T2DM remains poorly studied. Hence, the present study was designed to investigate the association of VDR gene SNP with complications of T2DM (disease phenotype) and correlated it with the serum levels of (25[OH]D) (intermediate phenotype) along with other clinical risk factors of T2DM. Genotyping was carried out in a total of 866 subjects, in which Group-I had Control subjects (n = 252), Group-II with T2DM without complications (n = 200); Group-III and Group-IV had subjects with micro (n = 216) and macrovascular (n = 198) complications respectively by PCR -RFLP. The 'G' allele of the VDR gene SNP is associated with a significant risk for T2DM, Diabetic Neuropathy (DN) and Coronary Artery Disease (CAD). In addition, subjects with mutant GG genotype had lower levels of (25[OH]D) in both T2DM and micro-macrovascular complications than AA genotype. Thus, VDR (rs1544410) SNP was found to be associated with decreased serum (25[OH]D) levels in both micro-macrovascular complications of T2DM among South Indian Population.

Association of NF-E2 Related Factor 2 (Nrf2) and inflammatory cytokines in recent onset Type 2 Diabetes Mellitus

We investigated the association of redox regulator Nuclear factor erythroid 2-related factor 2 (Nrf2) and inflammatory cytokines as well as clinical remission in patients with recent onset type 2 diabetes (DM). Blood was collected from 180 DM patients (105 males/75 females) and 150 control subjects (86 males/64 females). Blood glucose, HbA1c, lipid profile and Nrf2 levels were determined along with circulatory cytokines in study subjects. The data were adjusted with confounding factors such as age and sex using multiple logistic regression analysis. We found that Th1/Th2 and oxidative stress markers were significantly elevated, whereas Nrf2 and its downstream targets were decreased in peripheral blood mononuclear cells (PBMCs) of DM subjects when compared with control. The circulatory levels of Nrf2 showed a positive correlation with Th2 cytokines and negative correlation to Th1 cytokines. Further, the impaired insulin secretion in pancreatic β-cells observed due to cytokine stress has been restored by activation of Nrf2 as assessed by glucose-stimulated insulin secretion (GSIS). This study identifies Nrf2 plays a central role in skewing Th1 and Th2 dominance in the progression of diabetes.

Quercetin nanoparticle complex attenuated diabetic nephropathy via regulating the expression level of ICAM-1 on endothelium

The purpose of the study was to reveal the therapeutic effect of quercetin (QUE) nanoparticle complex on diabetic nephropathy (DN) by regulating the expression of intercellular adhesion molecular-1 (ICAM-1) on endothelium as compared to free QUE. QUE 10 mg/kg as a single abdominal subcutaneous injection daily for 8 weeks continuously in diabetic rats and 10 mg/kg QUE nanoparticle complex as a single abdominal subcutaneous injection every 5 days, continuously administered for 8 weeks to diabetic rats. Blood and left kidneys were collected; pathological change of kidney, renal function, oxidative stress level, blood glucose level, serum lipid, urine protein, and albumin/creatinine ratio were measured; and neutrophil adhesion, ICAM-1 expression, and CD11b⁺ cells infiltration were observed. Both QUE and QUE nanoparticle complex preconditioning ameliorated the pathological damage of kidney and improved renal function, alleviated renal oxidative stress injury, restricted inflammatory cells infiltration, and downregulated the ICAM-1 expression as compared to DN group, while QUE nanoparticle complex significantly alleviated this effect.

NLRP3 expression and urinary HSP72 in relation to biomarkers of inflammation and oxidative stress in diabetic nephropathy patients

Diabetic nephropathy (DN) is one of the major causes of end-stage renal disease. Nod-like receptors nucleotide-binding domain and leucine-rich repeat pyrin-3 domain (NLRP3) inflammasome displays a considerable role in the chronic inflammatory state observed in diabetic patients. Urinary heat shock protein 72 (uHSP72) is a sensitive and specific biomarker for the early detection of acute kidney injury. The aim of this study was to evaluate NLRP3 relative gene expression, its correlation with inflammatory and oxidative stress markers, and to assess the value of uHSP72 in the early detection of DN in type 2 diabetic patients with different degrees of DN. Forty-five type 2 diabetic patients: 15 normoalbuminuric, 15 microalbuminuric, 15 macroalbuminuric, in addition to 15 healthy controls were enrolled in this study. Clinical examination and routine laboratory investigations were performed. NLRP3 mRNA expression was assessed by real time polymerase chain reaction. Serum 8-hydroxy-2'-deoxyguanosine (8-OHdG), interleukin 1β (IL-1β), and uHSP72 levels were estimated by enzyme-linked immunosorbent assay. Serum chitotriosidase (CHIT1) activity was examined. NLRP3 mRNA relative expression, serum levels of 8-OHdG, IL-1β, and uHSP72, in addition to CHIT 1 activity were significantly increased in the macroalbuminuric patient group as compared to control and the other two diabetic groups. Also, a significant positive correlation was documented between the previously mentioned parameters and urinary albumin/creatinine ratio, serum creatinine, and HbA1c. Multiple linear regression analysis using urinary albumin/creatinine ratio as dependent variable confirmed that uHSP72 and NLRP3 mRNA relative expression were the independent predictors of DN (β were 0.432 and 0.448 respectively, P < 0.001). Receiver operating characteristic analyses revealed that both NLRP3 mRNA relative expression and uHSP72 levels were useful biomarkers discriminating DN patients from patients with type 2 diabetes mellitus (AUC were 0.957 and 0.983, respectively). uHSP72 may be considered as a novel potential diagnostic biomarker for the early detection of DN. Moreover, these data support the pivotal role of NLRP3 in the development and progression of DN. © 2017 IUBMB Life, 69(8):623-630, 2017.