Polymorphisms in dipeptidyl peptidase IV gene are associated with the risk of myocardial infarction in patients with atherosclerosis

Acute sleep deprivation (ASD) and cardioprotection: Impact of ASD on oxytocin-mediated sympathetic nervous activation preceding myocardial infarction

INTRODUCTION

This study explored how acute sleep deprivation (ASD) before myocardial ischemia influences oxytocin release from paraventricular (PVN) neurons and its correlation with sympathetic nervous system (SNS) activity post-acute sleep loss, impacting subsequent left ventricular (LV) remodeling following myocardial infarction (MI).

METHODS

The study was conducted in two phases: induction of ASD, inducing MI, blood sampling, euthanizing animals and collecting their heart and brain for histological and gene expression evaluations. The animals in first and second phase were euthanized 24 h and 14 days after MI, respectively.

RESULTS

Pre-MI ASD, accompanied by increased serum epinephrine levels within 24 h of MI, upregulated oxytocin and cFos expression in the PVN. Also, pre-MI ASD resulted in decreased serum PAB levels 14 days post-MI (P < 0.001). While notable echocardiographic changes were seen in MI versus sham groups, ASD demonstrated protective effects. This was evidenced by reduced infarct size, elevated TIMP1, MMP2, and MMP9 in the LV of SD + MI animals versus MI alone (P < 0.05). Additionally, histological analysis showed reduced LV fibrosis in pre-MI ASD subjects (P < 0.05).

CONCLUSION

Our study supports the notion that activation of oxytocin neurons within the PVN subsequent to ASD interacts with autonomic centers in the central nervous system. This enhanced sympathetic outflow to the heart prior to MI triggers a preconditioning response, thereby mediating cardioprotection through decreased oxidative stress biomarkers and regulated extracellular matrix (ECM) turnover.

A haplotype in the dipeptidyl peptidase 4 gene impacts glycemic-related traits of Brazilian older adults

Dipeptidyl peptidase 4 (DPP4) regulates various physiological pathways and has a pivotal role in glucose homeostasis. The objective of this study was to verify the association of a haplotype constituted by two single nucleotide polymorphisms (rs2268894 and rs6741949) in the DPP4 gene with type 2 diabetes mellitus (T2DM) and fasting glycemia-related variables in a sample of Brazilian older adults, taking serum levels and enzymatic activity of DPP4 into account. Clinical, biochemical, and anthropometric characteristics as well as DPP4 serum levels and enzymatic activity were determined in 800 elderly (≥60 years old) individuals. Assessment of polymorphic sites was performed by real-time PCR whereas haplotypes were inferred from genotypic frequencies. Statistical analyses compared measures and proportions according to T2DM diagnosis and DPP4 haplotypic groups. The most common haplotype consisted of the T-rs2268894/G-rs6741949 string, which was 20% more frequent among non-diabetics. Considering non-diabetic patients alone, carriers of the T/G haplotype had significantly lower levels of blood glucose, insulin, HOMA-IR index, and DPP4 activity. Among diabetic patients, the T/G haplotype was associated with lower DPP4 levels whereas glycemic scores were not affected by allelic variants. Our results suggested that the genetic architecture of DPP4 affects the glycemic profile and DPP4 serum levels and activity among elderly individuals according to the presence or absence of T2DM, with a possible implication of the T/G haplotype to the risk of T2DM onset.

Association of the rs17574 DPP4 Polymorphism with Premature Coronary Artery Disease in Diabetic Patients: Results from the Cohort of the GEA Mexican Study

Previously, it has been reported that hypoalphalipoproteinemia (HA) is associated with rs17574 DDP4 polymorphism. Considering that in diabetic patients, HA is often present and is a risk factor for premature coronary artery disease (pCAD), the study aimed to evaluate the association of this polymorphism with pCAD in diabetic individuals. We genotyped the rs17574 polymorphism in 405 pCAD patients with T2DM, 736 without T2DM, and 852 normoglycemic individuals without pCAD and T2DM as controls. Serum DPP4 concentration was available in 818 controls, 669 pCAD without T2DM, and 339 pCAD with T2DM. The rs17574 polymorphism was associated with lower risk of pCAD (padditive = 0.007; pdominant = 0.003, pheterozygote = 0.003, pcodominant1 = 0.003). In pCAD with T2DM patients, DPP4 levels were lower when compared with controls (p < 0.001). In the whole sample, individuals with the rs17574 GG genotype have the lowest protein levels compared with AG and AA (p = 0.039) carriers. However, when the same analysis was repeated separately in all groups, a significant difference was observed in the pCAD with T2DM patients; carriers of the GG genotype had the lowest protein levels compared with AG and AA (p = 0.037) genotypes. Our results suggest that in diabetic patients, the rs17574G DPP4 allele could be considered as a protective genetic marker for pCAD. DPP4 concentrations were lower in the diabetic pCAD patients, and the rs17574GG carriers had the lowest protein levels.

Role of Genetic Variants and Host Polymorphisms on COVID‐19: From Viral Entrance Mechanisms to Immunological Reactions

Coronavirus disease 2019 (COVID‐19), caused by a highly pathogenic emerging virus, is called severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Knowledge regarding the pathogenesis of this virus is in infancy; however, investigation on the pathogenic mechanisms of the SARS‐CoV‐2 is underway. In COVID‐19, one of the most remarkable characteristics is the wide range of disease manifestation and severity seen across individuals of different ethnic backgrounds and geographical locations. To effectively manage COVID‐19 in the populations, beyond SARS‐CoV‐2 detection, serological response assessment, and analytic techniques, it is critical to obtain knowledge about at‐risk individuals and comprehend the identified variations in the disease's severity in general and also in the populations' levels. Several factors can contribute to variation in disease presentation, including population density, gender and age differences, and comorbid circumstances including diabetes mellitus, hypertension, and obesity. Genetic factors presumably influence SARS‐CoV‐2 infection susceptibility. Besides this, COVID‐19 has also been linked with a higher risk of mortality in men and certain ethnic groups, revealing that host genetic characteristics may affect the individual risk of death. Also, genetic variants involved in pathologic processes, including virus entrance into cells, antiviral immunity, and inflammatory response, are not entirely understood. Regarding SARS‐CoV‐2 infection characteristics, the present review suggests that various genetic polymorphisms influence virus pathogenicity and host immunity, which might have significant implications for understanding and interpreting the matter of genetics in SARS‐CoV‐2 pathogenicity and customized integrative medical care based on population investigation.

Genetic factors presumably influence SARS‐CoV‐2 infection susceptibility.

Genetic variants were involved in the pathologic processes of SARS‐CoV‐2 infection.

Various genetic polymorphisms influence virus pathogenicity and host immunity.

Human leukocyte antigens (HLAs) may play a vital role in SARS‐CoV‐2 susceptibility.

Polymorphisms in several genes such as IL‐6, TMPRSS2, IFITM3, CD26, ACE, and DBP were associated with the COVID‐19 severity.

Effect of identified non-synonymous mutations in DPP4 receptor binding residues among highly exposed human population in Morocco to MERS-CoV through computational approach

Dipeptidyl peptidase 4 (DPP4) has been identified as the main receptor of MERS-CoV facilitating its cellular entry and enhancing its viral replication upon the emergence of this novel coronavirus. DPP4 receptor is highly conserved among many species, but the genetic variability among direct binding residues to MERS-CoV restrained its cellular tropism to humans, camels and bats. The occurrence of natural polymorphisms in human DPP4 binding residues is not well characterized. Therefore, we aimed to assess the presence of potential mutations in DPP4 receptor binding domain (RBD) among a population highly exposed to MERS-CoV in Morocco and predict their effect on DPP4 –MERS-CoV binding affinity through a computational approach. DPP4 synonymous and non-synonymous mutations were identified by sanger sequencing, and their effect were modelled by mutation prediction tools, docking and molecular dynamics (MD) simulation to evaluate structural changes in human DPP4 protein bound to MERS-CoV S1 RBD protein. We identified eight mutations, two synonymous mutations (A291 =, R317 =) and six non-synonymous mutations (N229I, K267E, K267N, T288P, L294V, I295L). Through docking and MD simulation techniques, the chimeric DPP4 –MERS-CoV S1 RBD protein complex models carrying one of the identified non-synonymous mutations sustained a stable binding affinity for the complex that might lead to a robust cellular attachment of MERS-CoV except for the DPP4 N229I mutation. The latter is notable for a loss of binding affinity of DPP4 with MERS-CoV S1 RBD that might affect negatively on cellular entry of the virus. It is important to confirm our molecular modelling prediction with in-vitro studies to acquire a broader overview of the effect of these identified mutations.

Plasma nesfatin-1 and DDP-4 levels in patients with coronary artery disease: Kozani study

Background

Nesfatin-1, a novel adipokine and dipeptidyl peptidase-4 (DPP4), a mam malian serine protease, are potent factors of atherosclerosis. In the present cross-sectional study, we investigated whether the plasma nesfatin-1 and DPP4 is associated with the prevalence and severity of coronary artery disease (CAD) with and without diabetes mellitus (DM).

Methods

We consecutively enrolled a total of 240 patients with significant CAD (previous revascularization or angiographically-proven coronary artery stenosis > 50%) presented with either unstable angina (UA, N = 76) or stable chronic CAD (SCAD, N = 165). 85 patients with at least 2 classical cardiovascular risk factors but without significant CAD served as controls. The severity of CAD was assessed using coronary angiography by the Gensini score. Clinical parameters, glycemic and lipid profile, high-sensitivity CRP (hsCRP), nesfatin-1 and DPP4 levels were assayed.

Results

No differences were found for age, sex, hypertension and diabetes distribution between groups. Low nesfatin-1 levels were found in both CAD groups (UA & SCAD) with respect to controls. The difference between UA and SCAD groups was marginally non-significant. There was a significant increase of DPP4 along UA to SCAD and control groups. Differences between groups remained unchanged in non-diabetic participants. Nesfatin-1 significantly correlated to hsCRP (r = − 0.287, p = 0.036), HOMA-IR (r = − 0.587, p = 0.007) and hyperlipidemia (r = − 0.331, p = 0.034). DPP4 was significantly associated with hs-CRP (r = 0.353 p < 0.001) and FPG (r = 0.202, p = 0.020) in univariate analysis, but those correlations were lost in multiple regression analysis. There was a negative correlation between nesfatin-1 and the severity of CAD, quantified by the Gensini score (r = − 0.511, p < 0.001), but no association was found for DPP4.

Conclusions

Serum DPP4 levels are increased in patients with CAD, while serum nesfatin-1 levels have a negative association with both the incidence and the severity of CAD. These results are independent of the presence of diabetes mellitus. In addition, both peptides have a strong association with hsCRP.

Trial registration ClinicalTrials.gov Identifier: NCT00306176

The rs12617336 and rs17574 Dipeptidyl Peptidase-4 Polymorphisms Are Associated With Hypoalphalipoproteinemia and Dipeptidyl Peptidase-4 Serum Levels: A Case-Control Study of the Genetics of Atherosclerotic Disease (GEA) Cohort

Dipeptidyl peptidase-4 (DPP4) can influence lipid homeostasis and atherosclerosis progression. We aimed to assess the association of DPP4 gene polymorphisms with hypoalphalipoproteinemia and DPP4 serum levels, in a cohort of Mexican individuals. Five DPP4 polymorphisms (rs12617336, rs12617656, rs1558957, and rs3788979, and rs17574) were genotyped in 748 participants with and 745 without hypoalphalipoproteinemia. The associations were evaluated using logistic regression analyses. Under inheritance models adjusted for confounding variables, the rs12617336 (OR = 0.22, P heterozygote = 0.001) and rs17574 (OR = 0.78, P additive = 0.022; OR = 0.73, P dominant = 0.012; OR = 0.73, P heterozygote = 0.017; OR = 0.72, P codominant 1 = 0.014) minor alleles were associated with a low risk of hypoalphalipoproteinemia. After the correction for multiple comparisons, the associations were marginal except the association of the rs12617336 that remaining significant. Additionally, both DPP4 minor alleles were associated with protection for the presence of insulin resistance (IR) (OR = 0.17, P heterozygote = 0.019 for rs12617336 and OR = 0.75, P additive = 0.049 for rs17574). The rs12617336 minor allele was also associated with a low risk of hyperinsulinemia (OR = 0.11, P heterozygote = 0.006). Differences in DPP4 levels were observed in individuals with rs17574 genotypes, the rs17574 GG genotype individuals had the lowest levels. Our data suggest that rs12617336 and rs17574 DPP4 minor alleles could be envisaged as protective genetic markers for hypoalphalipoproteinemia, IR, and hyperinsulinemia. The rs17574 GG genotype was associated with the lowest DPP4 levels.

Acute coronary syndrome in COVID-19 patients

Acute coronary syndrome (ACS) is caused by an acute mismatch between myocardial oxygen demand and its supply. This mechanism is largely associated with the progression of coronary atherosclerosis in combination with an inflammatory response, hypoxemia, and blood procoagulation. Patients with the coronavirus disease 2019 (COVID-19), aggravated by cardiovascular diseases and comorbidities, are at high risk of ACS.

Aim. To analyze the publications, which reflects the development of ACS in patients with COVID-19, its pathogenesis, and clinical course. Material and methods. Literature data were searched using Google Scholar, PubMed, ScienceDirect, and Cyberleninka services. The analysis included data from clinical guidelines on COVID-19, data from clinical studies, reports, and systematic reviews.

Results. This literature review summarizes and systematizes the data presented in modern publications, highlights the aspects of the clinical course and pathogenetic mechanisms underlying ACS in patients with COVID-19.

Conclusion. The pathogenesis of COVID-19 is inextricably associated with the widespread cytopathic effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), uncontrolled immune response that causes systemic inflammation, as well as the coagulation system activation. In patients with COVID-19, along with the atherosclerosis, these mechanisms significantly increase the risk of ACS and can worsen its in-hospital course.

Coronavirus: Pure Infectious Disease or Genetic Predisposition

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes novel coronavirus disease (COVID-19), is the seventh pathogenic coronavirus recently discovered in December 2019 in Wuhan, China. To date, our knowledge about its effect on the human host remains limited. It is well known that host genetic factors account for the individual differences in the susceptibility to infectious diseases. The genetic susceptibility factors to COVID-19 and its severity are associated with several unanswered questions. However, the experience gained from an earlier strain of coronavirus, SARS-CoV-1, which shows 78% genetic similarity to SARS-CoV-2 and uses the same receptor to bind to host cells, could provide some clues. It, therefore, seems possible to assemble new evidence in order to solve a potential genetic predisposition puzzle for COVID-19. In this chapter, the puzzle pieces, including virus entry receptors, immune response, and inflammation-related genes, as well as the probable genetic predisposition models to COVID-19, are discussed.

Association of dipeptidyl peptidase IV polymorphism, serum lipid profile, and coronary artery stenosis in patients with coronary artery disease and type 2 diabetes

Cardiovascular disease (CAD) is a devastating illness, but to date there are limited means of predicting a person's coronary stenosis severity and their prognosis. The study was performed to investigate the relationship between dipeptidyl peptidase 4(DPP4) gene polymorphisms and serum lipid profiles, as well as the severity of coronary artery stenosis in patients with CAD and type 2 diabetes (T2DM) for the first time.Herein, 201 patients with CAD and T2DM were enrolled in the Department of Cardiology, Shandong Provincial Qianfoshan Hospital. DPP4 rs3788979 and rs7608798 single nucleotide polymorphisms (SNPs) were genotyped. The general information of all patients was collected, and the associations between DPP4 SNPs and lipid profiles were detected. At the same time, association between SNP polymorphisms and the degree of coronary artery stenosis were analyzed.There was a significant difference in apolipoprotein B (ApoB) levels (P = .011) for the rs3788979 polymorphism, while no difference was identified in other blood lipids or with other mutations. SNP mutation of A to G in rs3788979 was associated with a reduced percentage of severe coronary artery stenosis in female patients (P = .023) as well as those with nosmoking (P = .030), nodrinking (P = 0.007), and nocardiovascular family history (P = 0.015).G allele of rs3788979 is associated with a reduced ApoB level. Besides, we suggest that G allele in rs3788979 may have a cardioprotective effect and prove to be a useful and specific measure when predicting a patient's coronary stenosis severity if diagnosed with CAD and T2DM.

Dipeptidylpeptidase-4 levels and DPP4 gene polymorphisms in patients with COVID-19. Association with disease and with severity

Background

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes de COVID-19 disease use as a principal receptor the angiotensin-converting enzyme-2 (ACE2). It has been suggested that dipeptidyl peptidase-4 (DPP4) can be another possible receptor for this virus. The present study aimed to establish if the DPP4 levels and DPP4 polymorphisms are associated with COVID-19 disease and its severity.

Methods

The study included 107 COVID-19 patients and 263 matched-healthy controls. Fifty patients required invasive mechanical ventilation. The DPP4 was quantified in serum using the Bioplex system. Based on the previous results and the functional prediction analysis, we select for the study 5 DPP4 polymorphisms (rs12617336, rs12617656, rs1558957, rs3788979, and rs17574) and these were determined using the 5´exonuclease TaqMan assays.

Results

Low levels of DPP4 were observed in COVID-19 patients (46.5 [33.1–57.7] ng/mL) when compared to healthy controls (125.3 [100.3–157.3] ng/mL) (P < 0.0001). Also, patients that required mechanical ventilation showed lower DPP4 levels (42.8 [29.8–56.9] ng/mL) than those that did not need this procedure (49.2 [39.9–65.6] ng/mL) (P = 0.012). DPP4 levels correlated negatively with age, fibrinogen, and platelet levels, and positively with albumin, alanine aminotransferase, and percentage of neutrophils. The DPP4 rs3788979 polymorphism was associated with a high risk of COVID-19 disease and, the TT genotype carriers had the lowest DPP4 levels.

Conclusions

In summary, in the present study, an association of low levels of DPP4 with COVID-19 disease and severity was found. The association of the DPP4 rs3788979 polymorphism with COVID-19 is also reported.

The potential effects of DPP-4 inhibitors on cardiovascular system in COVID-19 patients

With the outbreak of a new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the public healthcare systems are facing great challenges. Coronavirus disease 2019 (COVID-19) could develop into severe pneumonia, acute respiratory distress syndrome and multi-organ failure. Remarkably, in addition to the respiratory symptoms, some COVID-19 patients also suffer from cardiovascular injuries. Dipeptidyl peptidase-4 (DPP-4) is a ubiquitous glycoprotein which could act both as a cell membrane-bound protein and a soluble enzymatic protein after cleavage and release into the circulation. Despite angiotensin-converting enzyme 2 (ACE2), the recently recognized receptor of SARS-CoV and SARS-CoV-2, which facilitated their entries into the host, DPP-4 has been identified as the receptor of middle east respiratory syndrome coronavirus (MERS-CoV). In the current review, we discussed the potential roles of DPP-4 in COVID-19 and the possible effects of DPP-4 inhibitors on cardiovascular system in patients with COVID-19.

Polymorphisms in dipeptidyl peptidase 4 reduce host cell entry of Middle East respiratory syndrome coronavirus

Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) causes a severe respiratory disease in humans. The MERS-CoV spike (S) glycoprotein mediates viral entry into target cells. For this, MERS-CoV S engages the host cell protein dipeptidyl peptidase 4 (DPP4, CD26) and the interface between MERS-CoV S and DPP4 has been resolved on the atomic level. Here, we asked whether naturally-occurring polymorphisms in DPP4, that alter amino acid residues required for MERS-CoV S binding, influence cellular entry of MERS-CoV. By screening of public databases, we identified fourteen such polymorphisms. Introduction of the respective mutations into DPP4 revealed that all except one (Δ346-348) were compatible with robust DPP4 expression. Four polymorphisms (K267E, K267N, A291P and Δ346-348) strongly reduced binding of MERS-CoV S to DPP4 and S protein-driven host cell entry, as determined using soluble S protein and S protein bearing rhabdoviral vectors, respectively. Two polymorphisms (K267E and A291P) were analyzed in the context of authentic MERS-CoV and were found to attenuate viral replication. Collectively, we identified naturally-occurring polymorphisms in DPP4 that negatively impact cellular entry of MERS-CoV and might thus modulate MERS development in infected patients.

Reduced GLP-1 response to a meal is associated with the CTLA4 rs3087243 G/G genotype

Although insulitis is the characteristic main feature of type 1 diabetes mellitus (T1DM), many aspects of β cell loss still remain elusive. Immune dysregulation and alterations in the dipeptidyl-peptidase-4-incretin system might have a role in disease development, but their connection is poorly understood. We assessed the associations of a few selected, immunologically relevant single nucleotide gene variants with the DPP-4-incretin system in individuals with T1DM and in healthy controls. Prandial plasma (total, active) GLP-1 levels, serum DPP-4 activity, CD25 and CTLA-4 expression of T cells and DPP4 rs6741949, CTLA4 rs3087243, CD25 rs61839660 and PTPN2 rs2476601 SNPs were assessed in 33 T1DM patients and 34 age-, gender-, BMI-matched non-diabetic controls without a family history of T1DM. CTLA-4 expression was lower in the Foxp3+CD25+ regulatory T cells from individuals homozygous for the CTLA4 rs3087243-G variant compared to those who carry an A allele. Prandial plasma total GLP-1 levels 45 min after a standardized meal were reduced in individuals homozygous for the CTLA4 rs3087243 G major allele compared to A allele carriers both in the entire study population (with statistical power over 90%) and within the T1DM group. Here we report for the first time a reduced total prandial GLP-1 plasma concentration in individuals with the CTLA4 rs3087243 G/G genotype. One may speculate that immune response-related L cell damage might possibly explain this novel association.

DPP-4 inhibitors and heart failure: a potential role for pharmacogenomics

There remains an ongoing controversy regarding the safety of dipeptidyl peptidase-4 (DPP-4) inhibitors and the risk of developing heart failure (HF). In addition, none of the animal studies suggested a mechanism for the DPP-4 inhibitors and HF risk. To date, advances in pharmacogenomics have enabled the identification of genetic variants in DPP-4 gene. Studies have shown that genetic polymorphisms in the gene encoding DPP-4 may be associated with potential pathways involved in HF risk. This review discusses the contradictory findings of DPP-4 inhibitors and HF and a potential role for pharmacogenomics. Pharmacogenomics of DPP-4 inhibitors is promising, and genetic information from randomized control trials is urgently needed to gain a full understanding of the safety of DPP-4 inhibitors and the risk of HF.

Perspectives on cardiovascular effects of incretin-based drugs: From bedside to bench, return trip

Recently, cardiovascular outcome trials with glucose-lowering drugs used in type 2 diabetes mellitus, namely glucagon-like peptide-1 receptor agonists (GLP-1RA), liraglutide and semaglutide, showed a reduction in cardiovascular events, which had not been observed in trials with other incretin-based drugs, such as lixisenatide or with dipeptidyl peptidase-4 inhibitors (DPP4i). Mechanisms underlying the observed cardiovascular differences between DPP4i and GLP1-RA, and across individual GLP1-RA are poorly understood. This review is aimed at collecting and summarizing available evidence from experimental and mechanistic studies on the action of GLP1-RA and DPP4i on the cardiovascular system, both deriving from clinical and pre-clinical sources. The results of cardiovascular outcome trials are interpreted on the basis of the experimental preclinical data available, paying particular attention to the heart failure results, and suggesting some novel intriguing hypotheses to explain some of the unexpected findings of cardioprotection of incretin-based drugs. In particular, we discuss the possible contribution to the incretin cardiovascular effects of a direct cardiac action of GLP-1 metabolites through GLP-1 receptor-independent pathways, and of DPP4 substrates other than GLP-1.

Plasma DPP4 activity is associated with no-reflow and major bleeding events in Chinese PCI-treated STEMI patients

Dipeptidyl peptidase-4 (DPP4) is an important regulator of incretins and inflammation, and it is involved in the pathophysiological process of myocardial infarction (MI). This study investigated the role of plasma DPP4 activity (DPP4a) in patients with ST-segment elevation myocardial infarction (STEMI) who had undergone percutaneous coronary intervention (PCI). We recruited 747 consecutive PCI-treated STEMI patients from a tertiary referral center from January 2014 to October 2015. The outcomes of interest were the rates of no-reflow, in-hospital major adverse cardiac or cerebrovascular events (iMACCE), in-hospital complications (IHC) and in-hospital major bleeding. The DPP4a was lower in STEMI patients compared with the controls (p < 0.0001). Multivariate logistic-regression analyses (adjusted for confounding variables) showed that a 1 U/L increase in DPP4a was associated with an increased rate of no-reflow events (odds ratio [OR]: 1.07; 95% CI: 1.02-1.11; p < 0.01) and a decreased rate of major bleeding events (OR: 0.90; 95% CI: 0.82-0.98; p = 0.02). There were no associations between DPP4a and either iMACCE or IHC. In conclusions, high levels of DPP4a are independently associated with an increased rate of no-reflow events and a decreased rate of major bleeding events in PCT-treated STEMI patients.

Association between DPP4 gene polymorphism and serum lipid levels in Chinese type 2 diabetes individuals

OBJECTIVE

The goal of the genetic investigation was to identify the associations of serum lipid levels and DPP-4 variants in Chinese type 2 diabetes patients.

METHODS

We detected four variants of the DPP4 gene in 190 Chinese individuals with type 2 diabetes and tested for an association with dyslipidemia in 82 selected samples. Data including basic information, HbA1c, FPG, serum lipid parameters were collected. Statistical analysis was performed by SPSS 13.0 through ANOVA and χ² test.

RESULTS

The genetic polymorphism of rs4664443, rs3788979, rs7608798 and rs1558957 in Chinese type 2 diabetes were consistent with Hardy-Weinberg equilibrium. The CT genotype of rs4664443 suffered from higher serum TG (P=0.013), LDL (P=0.044) and ApoB (P=0.006) levels, whereas the TT genotype of rs7608798 exhibited a lower serum TG level (P=0.037). For rs3788979, the serum TG level (P=0.034) and BMI (P=0.04) were significantly different among genotypes. Moreover, serum TG and TC levels and BMI showed a positive correlation with the number unfavorable alleles, and individuals with more than two unfavorable alleles had higher TG (P=0.004), TC (P=0.011), and BMI (P=0.044) values.

CONCLUSIONS

This is the first study to investigate DPP4 allelic distributions and their association with dyslipidemia in Chinese type 2 diabetes patients, which may have clinical significance.

DPP-4 inhibitors in diabetic complications: role of DPP-4 beyond glucose control

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) are an emerging class of antidiabetic drugs that constitutes approximately fifty percent of the market share of the oral hypoglycemic drugs. Its mechanism of action for lowering blood glucose is essentially via inhibition of the rapid degradation of incretin hormones, such as glucagon-like peptide (GLP)-1 and gastric inhibitory polypeptide (GIP), thus the plasma concentration of GLP-1 increases, which promotes insulin secretion from the pancreatic β cells and suppresses glucagon secretion from the α cells. In addition to the direct actions on the pancreas, GLP-1 exhibits diverse actions on different tissues through its action on GLP-1 receptor, which is expressed ubiquitously. Moreover, DPP-4 has multiple substrates besides GLP-1 and GIP, including cytokines, chemokines, neuropeptides, and growth factors, which are involved in many pathophysiological conditions. Recently, it was suggested that DPP-4 is a new adipokine secreted from the adipose tissue, which plays an important role in the regulation of the endocrine function in obesity-associated type 2 diabetes. Consequently, DPP-4 inhibitors have been reported to exhibit cytoprotective functions against various diabetic complications affecting the liver, heart, kidneys, retina, and neurons. This review outlines the current understanding of the effect of DPP-4 inhibitors on the complications associated with type 2 diabetes, such as liver steatosis and inflammation, dysfunction of the adipose tissue and pancreas, cardiovascular diseases, nephropathy, and neuropathy in preclinical and clinical studies.

Association of DPP4 Gene Polymorphisms with Type 2 Diabetes Mellitus in Malaysian Subjects

Background

Genetic polymorphisms of the Dipeptidyl Peptidase 4 (DPP4) gene may play a role in the etiology of type 2 diabetes mellitus (T2DM). This study aimed to investigate the possible association of single nucleotide polymorphisms (SNPs) of the DPP4 gene in Malaysian subjects with T2DM and evaluated whether they had an effect on the serum levels of soluble dipeptidyl peptidase 4 (sDPP-IV).

Method

Ten DPP4 SNPs were genotyped by TaqMan genotyping assays in 314 subjects with T2DM and 235 controls. Of these, 71 metabolic syndrome (MetS) subjects were excluded from subsequent analysis. The odds ratios (ORs) and their 95% confidence interval (CIs) were calculated using multiple logistic regression for the association between the SNPs of DPP4 and T2DM. In addition, the serum levels of sDPP-IV were investigated to evaluate the association of the SNPs of DPP4 with the sDPP-IV levels.

Results

Dominant, recessive, and additive genetic models were employed to test the association of DPP4 polymorphisms with T2DM, after adjusting for age, race, gender and BMI. The rs12617656 was associated with T2DM in Malaysian subjects in the recessive genetic model (OR = 1.98, p = 0.006), dominant model (OR = 1.95, p = 0.008), and additive model (OR = 1.63, p = 0.001). This association was more pronounced among Malaysian Indians, recessive (OR = 3.21, p = 0.019), dominant OR = 3.72, p = 0.003) and additive model (OR = 2.29, p = 0.0009). The additive genetic model showed that DPP4 rs4664443 and rs7633162 polymorphisms were associated with T2DM (OR = 1.53, p = 0.039), and (OR = 1.42, p = 0.020), respectively. In addition, the rs4664443 G>A polymorphism was associated with increased sDPP-IV levels (p = 0.042) in T2DM subjects.

Conclusions

DPP4 polymorphisms were associated with T2DM in Malaysian subjects, and linked to variations in sDPP-IV levels. In addition, these associations were more pronounced among Malaysian Indian subjects.

DPP4 in Diabetes

Dipeptidyl-peptidase 4 (DPP4) is a glycoprotein of 110 kDa, which is ubiquitously expressed on the surface of a variety of cells. This exopeptidase selectively cleaves N-terminal dipeptides from a variety of substrates, including cytokines, growth factors, neuropeptides, and the incretin hormones. Expression of DPP4 is substantially dysregulated in a variety of disease states including inflammation, cancer, obesity, and diabetes. Since the incretin hormones, glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide (GIP), are major regulators of post-prandial insulin secretion, inhibition of DPP4 by the gliptin family of drugs has gained considerable interest for the therapy of type 2 diabetic patients. In this review, we summarize the current knowledge on the DPP4–incretin axis and evaluate most recent findings on DPP4 inhibitors. Furthermore, DPP4 as a type II transmembrane protein is also known to be cleaved from the cell membrane involving different metalloproteases in a cell-type-specific manner. Circulating, soluble DPP4 has been identified as a new adipokine, which exerts both para- and endocrine effects. Recently, a novel receptor for soluble DPP4 has been identified, and data are accumulating that the adipokine-related effects of DPP4 may play an important role in the pathogenesis of cardiovascular disease. Importantly, circulating DPP4 is augmented in obese and type 2 diabetic subjects, and it may represent a molecular link between obesity and vascular dysfunction. A critical evaluation of the impact of circulating DPP4 is presented, and the potential role of DPP4 inhibition at this level is also discussed.

The role of DPP4 activity in cardiovascular districts: in vivo and in vitro evidence

The introduction of incretin hormone-based therapies represents a novel therapeutic strategy, since these drugs not only improve glycemia with minimal risk of hypoglycemia, but also have other extraglycemic beneficial effects. These agents, which are effective in improving glucose control, could also have positive effects on the incidence of cardiovascular events. The aim of this review is to summarize the present literature about the role of dipeptidyl peptidase 4 (DPP4) in cardiovascular districts, not only strictly correlated to its effect on glucagon-like peptide-1 (GLP-1) circulating levels, but also to what is known about possible cardiovascular actions. Actually, DPP4 is known to be present in many cells and tissues and its effects go beyond purely metabolic aspects. Almost always the inhibition of DPP4 activity is associated with improved cardiovascular profile, but it has shown to possess antithrombotic properties and these different effects could be connected with a site and/or species specificity of DPP4. Certainly, DPP4 seems to exert many functions, both directly and indirectly, on cardiovascular districts, opening new possibilities of prevention and treatment of complications at this level, not only in patients affected by diabetes mellitus.