DPP-4 Inhibitors: Renoprotective Potential and Pharmacokinetics in Type 2 Diabetes Mellitus Patients with Renal Impairment

Nephroprotective Properties of Antidiabetic Drugs

Chronic kidney disease (CKD) is associated with increased morbidity and mortality, especially from cardiovascular (CV) causes, and especially in people with diabetes mellitus (DM). Already the presence of DM increases CV risk and potentiates the risk of CKD. Therefore, besides glycemic control, prevention and treatment of CKD to slow its progression are of clinical importance. A significant nephroprotective effect of novel antidiabetic drugs, namely sodium-glucose cotransporter 2 inhibitors (SGLT2-I) and glucagon-like peptide 1 receptor agonists (GLP1-RA), has been shown on top of their glucose-lowering effects and was confirmed in cardiovascular outcome trials. GLP1-RA mainly reduced the risk of macroalbuminuria, whereas SGLT2-I were also associated with a lower risk of declining glomerular filtration rate (GFR) over time. The nephroprotective effects of SGLT2-I are also evident in people without DM. According to current guidelines, SGLT2-I and/or GLP1-RA are recommended for people with DM who have chronic kidney disease and/or increased cardiovascular risk. However, other antidiabetic drugs offer nephroprotective properties, which will also be discussed in this review.

Recent Advances in the Emerging Therapeutic Strategies for Diabetic Kidney Diseases

Diabetic kidney disease (DKD) is one of the most common causes of end-stage renal disease worldwide. The treatment of DKD is strongly associated with clinical outcomes in patients with diabetes mellitus. Traditional therapeutic strategies focus on the control of major risk factors, such as blood glucose, blood lipids, and blood pressure. Renin–angiotensin–aldosterone system inhibitors have been the main therapeutic measures in the past, but the emergence of sodium–glucose cotransporter 2 inhibitors, incretin mimetics, and endothelin-1 receptor antagonists has provided more options for the management of DKD. Simultaneously, with advances in research on the pathogenesis of DKD, some new therapies targeting renal inflammation, fibrosis, and oxidative stress have gradually entered clinical application. In addition, some recently discovered therapeutic targets and signaling pathways, mainly in preclinical and early clinical trial stages, are expected to provide benefits for patients with DKD in the future. This review summarizes the traditional treatments and emerging management options for DKD, demonstrating recent advances in the therapeutic strategies for DKD.

Bile acid-based advanced drug delivery systems, bilosomes and micelles as novel carriers for therapeutics

Diabetes mellitus affects almost half a billion patients worldwide and results from either destruction of β-cells responsible for insulin secretion or increased tissue resistance to insulin stimulation and the reduction of glycemic control. Novel drug delivery systems can improve treatment efficacy in diabetic patients. The low aqueous solubility of most oral antidiabetic drugs decreases drug bioavailability; therefore, there is a demand for the use of novel methods to overcome this issue. The application of bile acids mixed micelles and bilosomes can provide an enhancement in drug efficacy. Bile acids are amphiphilic steroidal molecules that contain a saturated tetracyclic hydrocarbon cyclopentanoperhydrophenanthrene ring, and consist of three 6-membered rings and a 5-membered ring, a short aliphatic side chain, and a tough steroid nucleus. This review offers a comprehensive and informative data focusing on the great potential of bile acid, their salts, and their derivatives for the development of new antidiabetic drug delivery system.

Pharmacokinetics of a Fixed-Dose Combination Product of Dapagliflozin and Linagliptin and Its Comparison with Co-Administration of Individual Tablets in Healthy Humans

Dapagliflozin, a selective sodium–glucose co-transporter-2 inhibitor, and linagliptin, a competitive, reversible dipeptidyl peptidase-4 inhibitor, are commonly prescribed antidiabetic medications in general clinics. Since there are several merits to combining them in a fixed-dose combination product, this study investigated the pharmacokinetic equivalence between the individual component (IC) and fixed-combination drug product (FCDP) forms of dapagliflozin and linagliptin. A randomized, open-label, single-dose crossover study was conducted. All participants (n = 48) were randomly allocated to group A (period 1: ICs, period 2: FCDP) or group B (period 1: FCDP, period 2: ICs), and each group received either a single dose of IN-C009 (FCDP) or single doses of both dapagliflozin and linagliptin. There was no statistically significant difference found between the pharmacokinetic variables of FCDP and IC. The values of estimated geometric mean ratios and the 90% confidence interval for both maximum concentration and area under the plasma drug concentration–time curve were within the range of 0.8–1.25 for both dapagliflozin and linagliptin. The results of the clinical study demonstrated comparable pharmacokinetic characteristics between IC and FCDP forms of dapagliflozin and linagliptin. The combined use of dapagliflozin and linagliptin was safe and tolerable in both formulations.

Impact of DPP-4 inhibitors on plasma levels of BNP and NT-pro-BNP in type 2 diabetes mellitus

BACKGROUND

Dipeptidyl peptidase-4 inhibitors (DPP-4i) decrease glucose levels by regulating incretin peptides in type 2 diabetes mellitus (T2DM). This study aimed to determine the modulatory effect of DPP-4i on brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in patients with T2DM.

METHODS

PubMed, Embase and the Cochrane Library were systematically searched to identify randomized controlled trials (RCTs) evaluating the impact of DPP-4i on BNP or NT-pro-BNP. A fixed- or random-effects model was used for quantitative analysis, according to the heterogeneity. Sensitivity analysis and publication bias were performed using standard methods.

RESULTS

Nine trials with 3056 patients with T2DM were included. Meta-analysis revealed that DPP-4i did not significantly modulate the BNP (0.21 pg/mL, 95% CI - 2.36-2.79) or NT-pro-BNP level (- 7.34 pg/mL, 95% CI - 24.27-9.59). DPP-4i demonstrated no stronger effect on modulating BNP (5.17 pg/mL, 95% CI - 7.48-17.82) or NT-pro-BNP (- 9.95 pg/mL, 95% CI - 44.61-24.71) than active comparators. Pooled analysis was robust and stable after sensitivity analysis.

CONCLUSIONS

DPP-4i exhibits no significant effect on modulating BNP or NT-pro-BNP and shows no stronger effect than traditional antidiabetic agents in T2DM.

Diabetic kidney disease in children and adolescents: an update

Diabetic kidney disease (DKD), previously encountered predominantly in adult patients, is rapidly gaining center stage as a childhood morbidity and one that pediatric nephrologists are likely to encounter with increasing frequency. This is in large part due to the obesity epidemic and the consequent rise in type 2 diabetes in children and adolescents, as well as the more aggressive diabetes phenotype in today's youth with more rapid β-cell decline and faster development and progression of diabetes-related complications along with lower responsiveness to the treatments used in adults. DKD, an end-organ complication of diabetes, is at the very least a marker of, and more likely a predisposing factor for, the development of adverse cardiovascular outcomes and premature mortality in children with diabetes. On an optimistic note, several new therapeutic approaches are now available for the management of diabetes in adults, such as GLP1 receptor agonists, SGLT2 inhibitors, and DPP4 inhibitors, that have also been shown to have a favorable impact on cardiorenal outcomes. Also promising is the success of very low-energy diets in inducing remission of diabetes in adults. However, the addition of these pharmacological and dietary approaches to the management toolbox of diabetes and DKD in children and adolescents awaits thorough assessment of their safety and efficacy in this population. This review outlines the scope of diabetes and DKD, and new developments that may favorably impact the management of children and young adults with diabetes and DKD.

Diabetic Nephropathy and COVID-19: The Potential Role of Immune Actors

Nowadays, type II diabetes mellitus, more specifically ensuing diabetic nephropathy, and severe COVID-19 disease are known to be closely associated. The exact mechanisms behind this association are less known. An implication for the angiotensin-converting enzyme 2 remains controversial. Some researchers have started looking into other potential actors, such as neuropilin-1, mitochondrial glutathione, vitamin D, and DPP4. In particular, neuropilin-1 seems to play an important role in the underlying mechanism linking COVID-19 and diabetic nephropathy. We suggest, based on the findings in this review, that its up-regulation in the diabetic kidney facilitates viral entry in this tissue, and that the engagement of both processes leads to a depletion of neuropilin-1, which was demonstrated to be strongly associated with the pathogenesis of DN. More studies are needed to confirm this hypothesis, and research should be directed towards elucidating the potential roles of all these suggested actors and eventually discovering new therapeutic strategies that could reduce the burden of COVID-19 in patients with diabetic nephropathy.

Dipeptidyl Peptidase-4: A Potential Therapeutic Target in Diabetic Kidney Disease with SARS-CoV-2 Infection

Dipeptidyl peptidase-4 (DPP-4) is expressed ubiquitously in many tissues, including kidney, respiratory tract, and immune cells. Human DPP-4 has been identified as a functional receptor for the spike glycoprotein of the Middle East respiratory syndrome coronavirus. A large interface has been predicted in the docking of DPP-4/SARS-CoV-2 spike protein. Globally, 40% of diabetic patients develop diabetic kidney disease (DKD), a leading cause of end-stage renal disease. DPP-4 inhibitors possess anti-inflammatory properties which suggest their potential implication in DKD and SARS-CoV-2 immunopathogenesis.