Interactions among moderate/severe periodontitis, ADIPOQ-rs1501299, and LEPR-rs1137100 polymorphisms on the risk of type 2 diabetes in a Chinese population

Targeting Epigenetic Plasticity to Reduce Periodontitis-Related Inflammation in Diabetes: CBD, Metformin, and Other Natural Products as Potential Synergistic Candidates for Regulation? A Narrative Review

Periodontitis is unanimously accepted to be the sixth complication of diabetes mellitus (DM), while the inverse relationship of causality is still to be deciphered. Among the proposed mechanisms is gut dysbiosis, which is responsible for the systemic release of proinflammatory mediators. In this process, Gram-negative bacteria from the oral cavity enter the general circulation, leading to the emergence of bi-hormonal beta-pancreatic cells that lack the ability to secrete insulin. Additionally, epigenetic and adaptive mechanisms in affected cells may play a role in reducing inflammation. The release of reactive oxygen species, proinflammatory cytokines, and adipokines, such as interleukins, tumor necrosis factor alpha, leptin, prostaglandin E2, C-reactive protein, or matrix metalloproteinases, determine epigenetic changes, such as the methylation of DNA nucleotides or changes in the activity of histone acetylases/deacetylases. The management of periodontitis involves targeting inflammation, and its potential connection to epigenetic modulation observed in other chronic conditions may help to explain its role in preventing DM in affected patients. This review focuses on the key epigenetic changes in periodontitis that might contribute to DM development, and explores the mechanisms and novel multi-drug therapies that could help to prevent these effects.

Insight of the interrelationship and association mechanism between periodontitis and diabetes mellitus

Periodontitis and diabetes mellitus are two prevalent chronic diseases that have been recognized to exhibit a bidirectional relationship. Individuals with diabetes are more susceptible to periodontitis, and conversely, periodontitis can exacerbate glycemic control in diabetic patients. The underlying mechanisms of this interrelationship involve complex pathways, including inflammatory responses, altered immune functions, and microbial dysbiosis. The mechanistic insights into the interrelationship between periodontitis and diabetes mellitus revolve around the role of inflammation as a common link between the two diseases. Inflammatory mediators such as cytokines, chemokines, and prostaglandins play a crucial role in the pathogenesis and progression of the diseases. The dysregulation of the immune response in diabetes can exacerbate the inflammatory response in periodontitis, leading to increased tissue destruction and bone resorption. The chronic inflammation in periodontitis can contribute to insulin resistance and impaired glycemic control in diabetic patients. Future directions in research aim to further elucidate the molecular mechanisms underlying the interrelationship between periodontitis and diabetes mellitus. Modulating the inflammatory response, restoring microbial balance, and improving glycemic control hold promise in managing both conditions simultaneously. Herein, we will provide an overview of the interrelationship of periodontitis and diabetes mellitus, and retrospect the underlying mechanisms, which may inspire investigators with further research directions.

Genetic Markers of Insulin Resistance and Atherosclerosis in Type 2 Diabetes Mellitus Patients with Coronary Artery Disease

Type 2 diabetes mellitus (T2DM) is characterized by impaired insulin secretion on a background of insulin resistance (IR). IR and T2DM are associated with atherosclerotic coronary artery disease (CAD). The mechanisms of IR and atherosclerosis are known to share similar genetic and environmental roots. Endothelial dysfunction (ED) detected at the earliest stages of IR might be the origin of atherosclerosis progression. ED influences the secretion of pro-inflammatory cytokines and their encoding genes. The genes and their single nucleotide polymorphisms (SNPs) act as potential genetic markers of IR and atherosclerosis. This review focuses on the link between IR, T2DM, atherosclerosis, CAD, and the potential genetic markers CHI3L1, CD36, LEPR, RETN, IL-18, RBP-4, and RARRES2 genes.

The Bidirectional Relationship between Periodontal Disease and Diabetes Mellitus-A Review

Periodontitis is a chronic inflammatory disease caused by the presence of a bacterial biofilm known as dental plaque. This biofilm affects the supporting apparatus of the teeth, especially the periodontal ligaments and the bone surrounding the teeth. Periodontal disease and diabetes seem to be interrelated and in a bidirectional relationship, and have been increasingly studied in recent decades. For example, diabetes mellitus has a detrimental effect on periodontal disease, increasing its prevalence, extent, and severity. In turn, periodontitis negatively affects glycemic control and the course of diabetes. This review aims to present the most recently discovered factors that contribute to the pathogenesis, therapy, and prophylaxis of these two diseases. Specifically, the article focuses on microvascular complications, oral microbiota, pro- and anti-inflammatory factors in diabetes, and periodontal disease. As presented in this review, these two diseases require specific/ complementary therapeutic solutions when they occur in association, with new clinical trials and epidemiological research being necessary for better control of this interdependent pathogenic topic.

Association between LEPR polymorphism and susceptibility of osteoporosis in Chinese Mulao people

To explore the association between the single nucleotide polymorphism (SNP) of leptin receptor (LEPR) gene and the susceptibility to osteoporosis (OP) among Chinese Mulao people. A total of 738 people were involved. Bone mineral density (BMD) was examined by calcaneus ultrasound attenuation measurement. Six SNPs of LEPR were detected. The genotypes, allele frequencies, linkage disequilibrium, and haplotype were analyzed. BMD decreased with age and males had higher BMD than women. The proportion of normal bone mass decreased with age, and morbidity of OP increased. Three out of six SNPs showed a difference between OP and normal group. Individuals with AA genotype of rs1137100 in OP group outnumber the normal group, AA increased the risk of OP. In rs2767485, CT increased the risk of OP, C allele may be susceptible to OP. TT genotype of rs465555 was susceptible genotype of OP, T locus may be associated with OP. Strong linkage disequilibrium was detected among rs1137100, rs1137101, and rs4655555. Four haplotypes were constructed, among which, AACGCT and GGTGTA increased the risk of OP by 3.9 and 4.2 times, respectively, whereas, GGCGTA reduced 74% of OP susceptibility. The rs1137100, rs2767485, and rs465555 of LEPR were associated with OP in Chinese Mulao people.

Association of rs1137101 with hypertension and type 2 diabetes mellitus of Mongolian and Han Chinese

BACKGROUND

Hypertension (HTN) and type 2 diabetes mellitus (T2DM) are often coincident, and each condition is considered a risk factor for the other. Both occur frequently in the Inner Mongolia region of China. The reasons for differences in risk between Han and Mongolian ethnic groups are not known. The LEPR gene and its polymorphism, rs1137101 (Gln223Arg), are both considered risk factors for HTN and T2DM, but any role of rs1137101 in the occurrence of HTN + T2DM remains unclear for Mongolian and Han populations in the Inner Mongolia region.

AIM

To investigate the relationship between rs1137101 and the occurrence of HTN with T2DM in Mongolian and Han populations in Inner Mongolia.

METHODS

A total of 2652 subjects of Han and Mongolian ethnic origins were enrolled in the current study, including 908 healthy controls, 1061 HTN patients and 683 HTN patients with T2DM.

RESULTS

The association between the rs1137101 polymorphism and HTN with T2DM was analyzed, and differences between Han and Mongolian individuals assessed. There was a significant correlation between rs1137101 and HTN (co-dominant, dominant, over-dominant and log-additive models) and HTN + T2DM (co-dominant, dominant, over-dominant and log-additive models) after adjustment for sex and age in individuals of Mongolian origin. rs1137101 was significantly associated with HTN (co-dominant, recessive and log-additive models) and HTN + T2DM (co-dominant, dominant, over-dominant and log-additive models) in the Han Chinese population.

CONCLUSION

Mongolian and Han subjects from Inner Mongolia with HTN who had rs1137101 were protected against the development of T2DM. Allele A has the opposite impact on the occurrence of HTN in Mongolian and Han Chinese populations.

Effect of Genetic Variations in the ADIPOQ Gene on Susceptibility to Type 2 Diabetes Mellitus

BACKGROUND

ADIPOQ (adiponectin) affects fatty acid oxidation, glucose uptake, and glycogenesis, all of which are involved in the development of diabetes. As a result, ADIPOQ is being studied as a potential gene for type 2 diabetes mellitus (T2DM), which is a polygenic disease with genetic inheritance. This study aims to investigate the genetic variants (rs17846866 and rs1501299) in ADIPOQ gene with T2DM in the Saudi population.

METHODS

In this study, T2DM patients (n=96) and healthy controls (n=96) were recruited for molecular analysis for rs17846866 and rs1501299 single nucleotide polymorphisms (SNPs). Clinical data were analyzed using t-tests, HWE analysis, and genotype and allele frequencies were calculated for the rs17846866 and rs1501299 SNPs between T2DM cases and controls. ANOVA analysis was also used to investigate the relationship between the SNPs rs17846866 and rs1501299 and T2DM characteristics.

RESULTS

The current study results confirmed a positive association between clinical characteristics, HWE analysis, genotype, and allele frequencies in both rs17846466 and rs1501299 SNPs (p<0.05). In T2DM patients, ANOVA analysis with rs17846466 and rs1501299 SNPs in the ADIPOQ gene has no effect on any of the involved parameters (p>0.05).

CONCLUSION

This study concludes as rs17846866 and rs1501299 SNPs were strongly associated in the Saudi population with T2DM patients.

Association of type 2 diabetes mellitus and periodontal disease susceptibility with genome-wide association-identified risk variants in a Southeastern Brazilian population

OBJECTIVE

Genome-wide association studies (GWAS) and literature have identified polymorphisms in the KCNJ11, HNF1A, IRS1, TCF7L2, CDKAL1, CDKN2B, RPSAP52, GPR45 HHEX, IL18, and RUNX2 genes associated with type 2 diabetes mellitus (T2DM) and/or periodontitis (P) in diverse populations, and we sought to evaluate them as genetic risk variants for these diseases in the Brazilian population.

MATERIAL AND METHODS

Periodontal, glycemic, and lipid data were obtained from 931 individuals divided into: control (n = 334), periodontitis (P; n = 358), and periodontitis associated with T2DM (P + T2DM; n = 239). After genotyping, associations between polymorphisms and pathologies were tested by multiple logistic and linear regressions, adjusting for age, sex, and smoking habits.

RESULTS

Considering the studied subjects, the increased risk to develop periodontitis in the periodontitis P + T2DM group was found for HNF1A-rs7957197-TA, CDKAL1-rs7754840-CG, RPSAP52-rs1531343-GC, TCF7L2-rs7903146-TT, and CDKN2B-rs7018475-GG. The association of these genetic variants for TCF7L2 and CDKN2B was confirmed for female, never smokers, and poorly controlled P + T2DM. CDKN2B-rs7018475 was associated with worse glycemic condition and periodontal parameters.

CONCLUSION

These five reported genetic variants were associated in the studied Southeastern Brazilian population as genetic risk variants of periodontitis and T2DM associated to periodontitis as comorbidity. Gene-phenotype associations with sex and smoking habits and the CDKN2B-rs7018475 with the poor glycemic control and more severe periodontal conditions should be further investigated.

CLINICAL RELEVANCE

Polymorphisms in the CDKAL1-rs7754840, HNF1A-rs7957197, RPSAP52-rs1531343, TCF7L2-rs7903146, and CDKN2B-rs7018475 might predispose to periodontitis and T2DM associated with periodontitis. These findings may be useful in public health genomics and future advanced clinical practice, since genetic carriage can be measured before disease onset, being of potential great benefit for treatment planning and prognosis in early disease stages.

Association between Adiponectin Gene Polymorphism and Environmental Risk Factors of Type 2 Diabetes Mellitus among the Chinese Population in Hohhot

Objective

The aim of this study was to investigate the association between adiponectin gene polymorphisms rs10937273, rs1501299, rs182052, rs2241767, and rs266729 and environmental risk factors of type 2 diabetes mellitus (T2DM) in Hohhot. The study explored different models of gene-environment interactions, aimed at providing approaches for the prevention and control of T2DM in combination with the characteristics of the local population.

Methods

A case-control study was conducted including 406 Chinese participants, comprising 203 cases and 203 controls from various hospitals. Adiponectin (ADIPOQ) gene polymorphisms rs10937273, rs1501299, rs182052, rs2241767, and rs266729 were detected using an improved multiple ligation detection reaction technique. Generalized multifactor dimensionality reduction (GMDR) and logistic regression were conducted to analyze the associations between adiponectin gene polymorphisms and T2DM, as well as the interactions between adiponectin gene polymorphisms and environmental factors.

Results

ADIPOQ gene polymorphisms rs10937273, rs1501299, rs182052, rs2241767, and rs266729 were associated with type 2 diabetes. Based on the haplotype of the five adiponectin gene single-nucleotide polymorphism (SNP) loci, we found that G-G-A-A-C was a susceptible haplotype of T2DM (P < 0.05). Interaction analyses demonstrated associations between rs1501299 and central obesity (consistency = 80%, P = 0.011) and between rs266729 and rs182052 and central obesity (consistency = 70%, P = 0.011).

Conclusions

Our findings indicate that there is an interaction between the ADIPOQ gene and central obesity, which provides new insights into the prevention and treatment of T2DM.