Influence of IL-1β, STAT3 & 5 and TLR-5 gene polymorphisms on rheumatic heart disease susceptibility in north Indian population

Mechanistic insight: Linking cardiovascular complications of inflammatory bowel disease

Cardiovascular diseases (CVD) are the leading cause of mortality worldwide despite an aggressive reduction of traditional cardiovascular risk factors. Underlying inflammatory conditions such as inflammatory bowel disease (IBD) increase the risk of developing CVD. A broad understanding of the underlying pathophysiological processes between IBD and CVD is required to treat and prevent cardiovascular events in patients with IBD. This review highlights the commonality between IBD and CVD, including dysregulated immune response, genetics, environmental risk factors, altered gut microbiome, stress, endothelial dysfunction and abnormalities, to shed light on an essential area of modern medicine.

Effect of periodontitis on oxidative stress parameters in patients with rheumatic heart valve disease

OBJECTIVE

The aim of this study was to evaluate the effects of periodontitis on oxidative stress parameters by investigating serum and gingival crevicular fluid (GCF) total antioxidant capacity (TAOC), total oxidant status (TOS), and oxidative stress index (OSI) values in patients with rheumatic heart valve disease (RHVD).

MATERIALS AND METHODS

The study population comprised 76 patients, who were divided into four groups: chronic periodontitis with RVHD (RV-CP), periodontally healthy with RVHD (RV-C), systemically healthy with chronic periodontitis (CP), and systemically and periodontally healthy (C). Demographic, periodontal, and echocardiographic parameters were measured. Serum and GCF oxidative stress parameters were evaluated based on the OSI.

RESULTS

Similar serum oxidative stress parameters were found in all study groups (P ≥ 0.05). The GCF TAOC values of the C group were significantly higher than those of the other groups (P = 0.001). The GCF OSI values of the C group were significantly lower than those of the other groups (P = 0.001). The GCF TOS and OSI values of the RV-CP group were significantly higher than those of the CP and C groups (P = 0.001). The GCF TOS value of the RV-C group was significantly higher than those of the CP and C groups (P = 0.001).

CONCLUSIONS

Altered local oxidative stress profile was associated with the presence of periodontitis. Rheumatic heart valve disease may increase oxidative stress in individuals with chronic periodontitis.

The Human Leukocyte Antigen Locus and Rheumatic Heart Disease Susceptibility in South Asians and Europeans

Rheumatic heart disease (RHD), an autoinflammatory heart disease, was recently declared a global health priority by the World Health Organization. Here we report a genome-wide association study (GWAS) of RHD susceptibility in 1,163 South Asians (672 cases; 491 controls) recruited in India and Fiji. We analysed directly obtained and imputed genotypes, and followed-up associated loci in 1,459 Europeans (150 cases; 1,309 controls) from the UK Biobank study. We identify a novel susceptibility signal in the class III region of the human leukocyte antigen (HLA) complex in the South Asian dataset that clearly replicates in the Europeans (rs201026476; combined odds ratio 1.81, 95% confidence intervals 1.51-2.18, P = 3.48×10-10). Importantly, this signal remains despite conditioning on the lead class I and class II variants (P = 0.00033). These findings suggest the class III region is a key determinant of RHD susceptibility offering important new insight into pathogenesis while partly explaining the inconsistency of earlier reports.

Genetic variants in rheumatic fever and rheumatic heart disease

Genetic association studies in rheumatic heart disease (RHD) have the potential to contribute toward our understanding of the pathogenetic mechanism, and may shed light on controversies about RHD etiology. Furthermore, genetic association studies may uncover biomarkers that can be used to identify susceptible individuals, and contribute toward developing vaccine and novel therapeutic targets. Genetic predisposition to rheumatic fever and RHD has been hypothesized by findings from familial studies and observed associations between genes located in the human leukocyte antigens on chromosome 6p21.3 and elsewhere in the genome. We sought to summarize, from published Genetic association studies in RHD, evidence on genetic variants implicated in RHD susceptibility. Using HuGENet™ systematic review methods, we evaluated 66 studies reporting on 42 genes. Existing meta-analyses of candidate gene studies suggest that TGF-β1 [rs1800469], and IL-1β [rs2853550] single nucleotide polymorphisms (SNPs) contribute to susceptibility to RHD, whereas the TNF-α [rs1800629 and rs361525], TGF-β1 [rs1800470 and rs4803457], IL-6 [rs1800795], IL-10 [rs1800896] were not associated with RHD. However, candidate gene studies in RF/RHD are relatively small, thus lacking statistical power to identify reliable and reproducible findings, emphasizing the need for large-scale multicenter studies with different populations.