Effect of dipeptidyl-peptidase-4 inhibitors on C-reactive protein in patients with type 2 diabetes: a systematic review and meta-analysis

Effect of dipeptidyl peptidase-4 inhibitors on tumor necrosis factor alpha levels in patients with type 2 diabetes mellitus

AIMS

Dipeptidyl peptidase-4 inhibitors (DPP-4i) served as oral antidiabetic agents for treatment of type 2 diabetes mellitus (T2DM). Although an action on glucose homeostasis was identified, no well-rounded illustration had been established on the changes of tumor necrosis factor alpha (TNF-alpha) levels during DPP-4i treatment. This study aimed to explore the anti-inflammatory effect of DPP-4i on TNF-alpha in patients with T2DM.

METHODS

PubMed, Embase and Cochrane Library were systematically searched from inception to May 31, 2024. Randomized controlled trials exploring the impact of DPP-4i on TNF-alpha levels were identified. Risk of bias was assessed according to the Cochrane criteria. A fixed or random-effects model was selected to pool estimate on whether the heterogeneity was present. Subgroup analysis were performed to explore the potential factors that influenced heterogeneity. Related meta-analysis was conducted with the software of Revman 5.3 and STATA 12.0.

RESULTS

Eleven trials involving 884 participants with T2DM were included. Pooled estimates suggested that DPP-4i did not significantly modulate TNF-alpha levels (WMD, - 0.70, 95% CI - 1.94 to 0.53, P = 0.26) in T2DM. DPP-4i produced a significant effect on TNF-alpha (WMD, - 4.50 pg/mL, 95% CI - 4.68 to - 4.32, P < 0.00001) when compared to placebo, and a comparable effect was demonstrated on TNF-alpha (WMD, 0.10 pg/mL, 95% CI - 0.11 to 0.30, P = 0.35) in comparison with active agents. Estimate was stable according to the sensitivity test. Subgroup analysis revealed that heterogeneity might not correlate with baseline glycated hemoglobin (HbA1c), age or treatment duration.

CONCLUSIONS

A significant effect of DPP-4i on TNF-alpha levels was present in T2DM when compared to placebo. Administration of DPP-4i produced no significant effect on TNF-alpha in comparison with active comparators. Further studies with large samples should be performed to illustrate the impact of DPP-4i on TNF-alpha levels in T2DM. Trial registration International Prospective Register for Systematic Review (PROSPERO) number: CRD42020185479.

GLP-1 Analogs, SGLT-2, and DPP-4 Inhibitors: A Triad of Hope for Alzheimer's Disease Therapy

Alzheimer's is a prevalent, progressive neurodegenerative disease marked by cognitive decline and memory loss. The disease's development involves various pathomechanisms, including amyloid-beta accumulation, neurofibrillary tangles, oxidative stress, inflammation, and mitochondrial dysfunction. Recent research suggests that antidiabetic drugs may enhance neuronal survival and cognitive function in diabetes. Given the well-documented correlation between diabetes and Alzheimer's disease and the potential shared mechanisms, this review aimed to comprehensively assess the potential of new-generation anti-diabetic drugs, such as GLP-1 analogs, SGLT-2 inhibitors, and DPP-4 inhibitors, as promising therapeutic approaches for Alzheimer's disease. This review aims to comprehensively assess the potential therapeutic applications of novel-generation antidiabetic drugs, including GLP-1 analogs, SGLT-2 inhibitors, and DPP-4 inhibitors, in the context of Alzheimer's disease. In our considered opinion, antidiabetic drugs offer a promising avenue for groundbreaking developments and have the potential to revolutionize the landscape of Alzheimer's disease treatment.

Immunotropic effects of hypoglycemic agents on coronavirus infection: a view from the perspective of pharmacogenetics

Diabetes mellitus is a predictor of the severe course of a new coronavirus infection and high mortality, in this regard, the selection of appropriate hypoglycemic therapy is a vital issue. In this article, we paid attention to dipeptidyl peptidase-4 (DPP-4) inhibitors, since this group of drugs has features like low risk of hyperglycemia and immuno-mediated effects. For the most effective treatment, it is necessary to take into account the individual characteristics of each patient, namely, the achievements of pharmacogenetics. The genetic variability of the response to therapy with DPP-4 inhibitors is due to a variety of polymorphisms, several main variations are considered in the review. The ambiguity of the available studies on the effectiveness of DPP-4 inhibitors in patients with type 2 diabetes with COVID-19 indicates the need to continue pharmacogenetic studies. The combination of knowledge about the subtleties of the mechanisms of pharmacological action of drugs and individual characteristics of pharmacodinamics will ensure the greatest effectiveness and safety of personalized therapy of diabetes mellitus against the background of coronavirus infection.

The Anti-Inflammatory Effect of Novel Antidiabetic Agents

The incidence of type 2 diabetes (T2DM) has been increasing worldwide and remains one of the leading causes of atherosclerotic disease. Several antidiabetic agents have been introduced in trying to regulate glucose control levels with different mechanisms of action. These agents, and sodium-glucose cotransporter-2 inhibitors in particular, have been endorsed by contemporary guidelines in patients with or without T2DM. Their widespread usage during the last three decades has raised awareness in the scientific community concerning their pleiotropic mechanisms of action, including their putative anti-inflammatory effect. In this review, we delve into the anti-inflammatory role and mechanism of the existing antidiabetic agents in the cardiovascular system and their potential use in other chronic sterile inflammatory conditions.

Executive Summary from Expert consensus on effectiveness and safety of iDPP-4 in the treatment of patients with diabetes and COVID-19

BACKGROUND

This consensus aims to clarify the role of Dipeptidyl Peptidase-4 inhibitors (iDPP-4) in managing patients with diabetes during the COVID-19 pandemic.

MATERIALS AND METHODS

A PubMed bibliographic search was carried out (December 2019-February 2021). Oxford methodology was used for the evaluation of evidence and possible recommendations were established by consensus.

RESULTS

Diabetes appears to be an independent factor in COVID-19 disease (evidence 2b). No increased risk of contagion with iDPP-4 is demonstrated (evidence 2b), and its use has been shown to be safe (evidence 2b). The use of this drug may present a specific benefit in reducing mortality, particularly in in-hospital use (evidence 2a), reducing admission to intensive care units (evidence 2b) and the need for mechanical ventilation (evidence 2b).

CONCLUSIONS

The use of iDPP-4 appears to be safe in patients with COVID-19, and quality studies are needed to clarify their possible advantages further.

Association between dipeptidyl peptidase-4 inhibitors use and leptin in type 2 diabetes mellitus

BACKGROUND

Dipeptidyl peptidase-4 inhibitors (DPP-4i) provide a unique antihyperglycemic effect by regulating incretin peptides in type 2 diabetes mellitus (T2DM) patients who are inadequately controlled with insulin therapy. The aim of this study was to investigate the impact of DPP-4i on leptin concentrations in subjects with T2DM.

METHODS

Randomized controlled trials (RCTs) with comparators were systematically searched through PubMed, Embase, and the Cochrane Library. Quantitative analysis was performed with a fixed or random-effects model according to heterogeneity. Publication bias was evaluated by using the standard methods for sensitivity analysis.

RESULTS

Ten trials with 698 patients with T2DM were included. Pooled analysis demonstrated that DPP-4i did not significantly change leptin concentrations (1.31 ng/mL, 95 % CI - 0.48 to 3.10). DPP-4i exerted effects on modulating leptin levels compared to active comparators (0.21 ng/mL, 95 % CI - 1.37 to 1.78). Meta-analysis was powerful and stable after sensitivity analysis.

CONCLUSIONS

DPP-4i did not modulate leptin concentrations in T2DM and exerted no stronger effects than traditional antidiabetic agents.

Efficacy and Safety of the Novel Dipeptidyl Peptidase-4 Inhibitor Gemigliptin in the Management of Type 2 Diabetes: A Meta-Analysis

BACKGROUND

No meta-analysis has holistically analysed and summarised the efficacy and safety of gemigliptin in type 2 diabetes. The meta-analysis addresses this knowledge gap.

METHODS

Electronic databases were searched for randomised controlled trials (RCTs) involving diabetes patients receiving gemigliptin in the intervention arm and placebo/active comparator in the control arm. The primary outcome was change in haemoglobin A1c (HbA1c). The secondary outcomes were alterations in glucose, glycaemic targets, lipids, insulin resistance, and adverse events.

RESULTS

Data from 10 RCTs involving 1,792 patients were analysed. Four had an active control group (ACG), with metformin/dapagliflozin/sitagliptin/glimepiride as the active comparator; six had a passive control group (PCG), with placebo/rosuvastatin as controls. HbA1c reduction by gemigliptin at 24 weeks was comparable to ACG (mean difference [MD], 0.09%; 95% confidence interval [CI], -0.06 to 0.23; P=0.24; I2=0%; moderate certainty of evidence [MCE]), but superior to PCG (MD, -0.91%; 95% CI, -1.18 to -0.63); P<0.01; I2=89%; high certainty of evidence [HCE]). Gemigliptin was superior to PCG regarding achieving HbA1c <7% (12 weeks: odds ratio [OR], 5.91; 95% CI, 1.34 to 26.08; P=0.02; I2=74%; 24 weeks: OR, 4.48; 95% CI, 2.09 to 9.60; P<0.01; I2=69%; HCE). Gemigliptin was comparable to ACG regarding achieving HbA1c <7% after 24 weeks (OR, 0.92; 95% CI, 0.52 to 1.63; P=0.77; I2=66%; MCE). Adverse events were similar between the gemigliptin and control groups (risk ratio [RR], 1.06; 95% CI, 0.82 to 1.36; P=0.66; I2=35%; HCE). The gemigliptin group did not have increased hypoglycaemia (RR, 1.19; 95% CI, 0.62 to 2.28; P=0.61; I2=19%; HCE).

CONCLUSION

Gemigliptin has good glycaemic efficacy and is well-tolerated over 6 months of use.

DPP-4 inhibition and COVID-19: From initial concerns to recent expectations

Dipeptidyl peptidase-4 inhibitors (DPP-4is) have gained a key place in the management of type 2 diabetes mellitus (T2DM) essentially because of their good safety profile even in the frail population. DPP-4, originally known as 'T-cell antigen CD26', is expressed in many immune cells and regulates their functions, so the initial concern over the use of DPP-4is was the possible increased susceptibility to infections. Furthermore, because of the high affinity between human DPP-4 and the spike (S) receptor-binding domain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it was suspected that this virus, responsible for coronavirus disease 2019 (COVID-19), might be able to use the DPP-4 enzyme as a functional receptor to gain entry into the host. However, DPP-4is also exert anti-inflammatory effects, which could be beneficial in patients exposed to cytokine storms due to COVID-19. Yet, when observational (mostly retrospective) studies compared clinical outcomes in DPP-4i users vs non-users among diabetes patients with COVID-19, the overall results regarding the risk of progression towards more severe forms of the disease and mortality were heterogeneous, thereby precluding any definite conclusions. Nevertheless, new expectations have arisen following recent reports of significant reductions in admissions to intensive care units and mortality in DPP-4i users. However, given the limitations inherent in such observational studies, any available results should be considered, at best, as hypothetical and only suggestive of potentially substantial benefits with DPP-4is in diabetes patients with COVID-19. While the safe use of DPP-4is in COVID-19 patients appears to be an acceptable hypothesis, all such positive findings still need to be confirmed in randomized controlled trials (a few of which are currently ongoing) before any recommendations can be made for clinical practice.

Predictors of adverse in-hospital outcome and recovery in patients with diabetes mellitus and COVID-19 pneumonia in Iraq

BACKGROUND AND AIMS

There is limited data about the prognosis and impact of COVID-19 pneumonia on patients with diabetes mellitus (DM). We aimed to assess blood indices, ECG markers of sudden death and malignant arrhythmias on admission, and diabetes lowering drugs as possible predictors of adverse in-hospital outcome and COVID-19 pneumonia recovery status.

METHODS

A retrospective study included patients with newly diagnosed COVID-19 pneumonia from August 20, to October 5, 2020.

RESULTS

A total of 192 patients with COVID-19 pneumonia were included in the present study, of whom 67 patients had DM. Low lymphocytes % [0.4(0.1-0.9), P = .011] and QTc interval prolongation [0.4(0.1-0.8), P = .022] were associated with increased length of ICU stay. On the other hand, metformin use [0.3(0.2-4), P = .032] and DPP-4 inhibitors use [0.3(0.2-3), P = .040] were associated with decreased length of ICU stay. QTc interval prolongation [0.4(0.1-0.9), P = .017] was associated with increased length of hospital stay, while using metformin [0.4(0.2-3), P = .022] was associated with decreased length of hospital stay. Low lymphocytes % [0.5(0.4-1.6), P = .001], insulin use [0.4(0.3-5), P = .003], and old age [0.5(0.1-2.3), P = .025] were associated with extensive lung injury. The risk for in-hospital death was associated with high neutrophil% [1(1-1.4), P = .045], while metformin use was associated with decreased risk for in-hospital death [0.1(0.1-0.6), P = .025]. Insulin use [0.3(0.2-4), P = .013] was associated with partial recovery following acute COVID pneumonia.

CONCLUSIONS

Metformin and DPP-4 inhibitors use were associated with favorable in-hospital outcomes, while insulin use was associated with extensive lung injury and post-acute COVID-19 pneumonia partial recovery.

Anti-inflammatory properties of antidiabetic drugs: A "promised land" in the COVID-19 era?

Inflammation is implicated in the development and severity of the coronavirus disease 2019 (COVID-19), as well as in the pathophysiology of diabetes. Diabetes, especially when uncontrolled, is also recognized as an important risk factor for COVID-19 morbidity and mortality. Furthermore, certain inflammatory markers [i.e. C-reactive protein (CRP), interleukin-6 (IL-6) and ferritin] were reported as strong predictors of worse outcomes in COVID-19 positive patients. The same biomarkers have been associated with poor glycemic control. Therefore, achieving euglycemia in patients with diabetes is even more important in the era of the COVID-19 pandemic. Based on the above, it is clinically interesting to elucidate whether antidiabetic drugs may reduce inflammation, thus possibly minimizing the risk for COVID-19 development and severity. The present narrative review discusses the potential anti-inflammatory properties of certain antidiabetic drugs (i.e. metformin, pioglitazone, sitagliptin, linagliptin, vildagliptin, alogliptin, saxagliptin, liraglutide, dulaglutide, exenatide, lixisenatide, semaglutide, empagliflozin, dapagliflozin, canagliflozin), with a focus on CRP, IL-6 and ferritin.

DPP4/CD32b/NF-κB Circuit: A Novel Druggable Target for Inhibiting CRP-Driven Diabetic Nephropathy

Diabetic nephropathy (DN) is a major cause of end-stage renal disease, but treatment remains ineffective. C-reactive protein (CRP) is pathogenic in DN, which significantly correlated with dipeptidyl peptidase-4 (DPP4) expression in diabetic patients with unknown reason. Here, using our unique CRP^tg-db/db mice, we observed human CRP markedly induced renal DPP4 associated with enhanced kidney injury compared with db/db mice. Interestingly, linagliptin, a US Food and Drug Administration (FDA)-approved specific DPP4 inhibitor, effectively blocked this CRP-driven DN in the CRP^tg-db/db mice. Mechanistically, CRP evoked DPP4 in cultured renal tubular epithelial cells, where CD32b/nuclear factor κB (NF-κB) signaling markedly enriched p65 binding on the DPP4 promoter region to increase its transcription. Unexpectedly, we further discovered that CRP triggers dimerization of DPP4 with CD32b at protein level, forming a novel DPP4/CD32b/NF-κB signaling circuit for promoting CRP-mediated DN. More importantly, linagliptin effectively blocked the circuit, thereby inhibiting the CRP/CD32b/NF-κB-driven renal inflammation and fibrosis. Thus, DPP4 may represent a precise druggable target for CRP-driven DN.