Search Results (417)

Background/Objectives: Patients with diabetes mellitus face increased risk of severe outcomes and mortality from COVID-19. Dipeptidyl peptidase-4 (DPP-4) inhibitors, widely used antidiabetic agents, are hypothesized to affect COVID-19 outcomes via anti-inflammatory and immune-modulating mechanisms. However, real-world evidence, especially in Korean populations, remains limited. Methods: We conducted a retrospective cohort study using Korea’s nationwide Health Insurance Review and Assessment (HIRA) database. Adults with diabetes hospitalized for confirmed COVID-19 between 1 March 2021, and 28 February 2022, were included and stratified by DPP-4 inhibitor use. The primary outcome was 30-day all-cause mortality. Cox proportional hazards models adjusted for age, sex, and comorbidities estimated hazard ratios (HRs). Subgroup analyses examined angiotensin receptor blocker (ARB) and insulin use. Results: Among 16,134 eligible patients, 7082 received DPP-4 inhibitors. The 30-day mortality rate was lower in DPP-4 inhibitor users than non-users (4.3% vs. 10.3%, p < 0.0001). Adjusted analyses showed DPP-4 inhibitor use was associated with reduced mortality risk (adjusted HR: 0.455; 95% CI: 0.414–0.499). Subgroup analyses yielded consistent results across ARB and insulin users. Kaplan-Meier curves demonstrated higher survival probability in the DPP-4 inhibitor group. Conclusions: In this nationwide Korean cohort, DPP-4 inhibitor use was associated with lower mortality among hospitalized diabetic patients with COVID-19. While these findings suggest a potential benefit, causality cannot be confirmed due to the observational design. Prospective studies are needed to verify these associations and explore underlying mechanisms. Full article

SARS-CoV and MERS-CoV are two coronaviruses that have received significant attention due to their high pathogenicity and mortality rates in human populations. In this study, we compared their evolutionary dynamics to provide a One Health perspective on their differences in terms of the results of disease control. The phylogenetic network of SARS-CoVs showed that human isolates gathered into a “super-spreader” cluster and were distinct from civet isolates. In contrast, dromedary camel- and human-isolated MERS-CoVs were clustered together. Thus, most clades of MERS-CoV can infect humans, and MERS-CoVs seem to more easily spill over the animal-to-human interface. Additionally, the civet can be easily controlled, while the intermediate host (dromedary camels) of MERS-CoV is an important livestock species, so it is impossible to eliminate all animals. This further leads to difficulties in disease control in MERS. Although MERS-CoVs are endemic to dromedary camels in both the Middle East and Africa, human infections are mainly linked to the Middle East. The nucleotide sequences of the MERS-CoV receptor gen (dipeptidyl peptidase 4 (DPP4)) from 30 Egyptians, 36 Sudanese, and 34 Saudi Arabians showed little difference. These findings suggest that the observed disparities in MERS prevalence between populations in the Middle East and Africa may be more strongly attributed to inadequate disease surveillance and the limited camel-to-human transmission of clade C MERS-CoV in Africa, rather than variations in DPP4 gene. Full article

Background/Objectives: Essential amino acid (EAA) supplementation is often employed in sportive and clinical nutrition due to EAAs’ role in muscle mass maintenance and growth. EAAs are also involved in insulin and glucagone regulation in diabetes management, but only few reports investigate their possible implication as dipeptidyl peptidase-IV (DPP-IV) inhibitors and their effect on the stability and secretion of enteroendocrine hormones. A blend of EAAs (called GAF) available as a food supplement, in a specific qualitative and quantitative ratio, was investigated to address its in vitro bioaccessibility, its hypoglycemic properties in vitro and in situ on cellular models, and its safety on intestinal Caco-2 cells. Methods: GAF was subjected to the INFOGEST static digestion protocol, producing the iGAF sample. iGAf DPP-IV inhibitory properties were investigated both in vitro and in situ on Caco-2 cells. Then, STC-1 enteroendocrine cells were employed alone and in co-culture with Caco-2 cells to evaluate iGAF’s impact on glucagon-like peptide 1 (GLP-1) hormone secretion. Results: The study demonstrates that the present EAAs blend is stable and bioaccessible after simulated gastrointestinal digestion, and it is safe at the intestinal cellular level. It inhibits DPP-IV enzyme both in vitro and in situ and promotes GLP-1 secretion by enteroendocrine cells. Conclusions: The sample demonstrated safety at the intestinal level and showed hypoglycemic properties by acting on a dual synergic mechanism that involves DPP-IV enzyme inhibition and GLP-1 hormone stimulation. Full article

Background: Numerous studies have demonstrated the beneficial effects of sodium-glucose cotransporter-2 (SGLT2) inhibitors on cardiovascular and renal outcomes in patients with heart failure and chronic kidney disease. However, whether SGLT2 inhibitors are also associated with a reduced risk of tinnitus has not been investigated. Objective: This study aimed to investigate the association between SGLT2 inhibitor therapy and the incidence of tinnitus in patients with type 2 diabetes. Methods: This retrospective cohort study was based on data from a nationally representative database of primary care practices in Germany from 2012 to 2023. Patients with type 2 diabetes who were treated with metformin and additionally received either an SGLT2 inhibitor or a dipeptidyl peptidase-4 (DPP4) inhibitor were included. Patients with a previous diagnosis of tinnitus were excluded. The primary outcome was the first tinnitus diagnosis documented by a primary care physician. The SGLT2 and DPP4 cohorts were compared for tinnitus incidence using Kaplan–Meier analysis and multivariable Cox regression. Results: 66,750 patients with SGLT2 inhibitors and 82,830 with DPP4 inhibitors were analyzed. The cumulative 5-year incidence of tinnitus was 1.9% in both groups. The multivariable regression analysis did not show a significant association between SGLT2 therapy and the occurrence of a tinnitus diagnosis (HR: 1.04; 95% CI: 0.89–1.21). Conclusion: There was no difference in tinnitus incidence between patients with SGLT2 or DPP4 inhibitors. The causes could lie in the heterogeneous, not purely vascular, etiology of tinnitus in general practitioners’ practices. Future studies should include further clinical data, including confirmed hearing impairments. Full article

Background: There is growing evidence suggesting that SARS-CoV-2 may contribute to metabolic dysfunction. SARS-CoV-2 infection is associated with systemic inflammation, oxidative stress, and metabolic dysregulation, all of which may impair liver function and promote glucose intolerance. This study investigated the role of SARS-CoV-2, specifically its Main Protease (M^pro), in accelerating insulin resistance and metabolic dysfunction in HepG2 cells in vitro. Methods: HepG2 cells were treated with varying concentrations of M^pro (2.5, 5, 10, 20, 40, 80, and 160 nmol/mL) for 24 h to assess cytotoxicity and glucose uptake. Based on initial findings, subsequent assays focused on higher concentrations (40, 80, and 160 nmol/mL). The effects of M^pro on cell viability, protein kinase B (AKT) expression, matrix metallopeptidase-1 (MMP1), dipeptidyl peptidase 4 (DPP4), interleukin-6 (IL-6) expression, and lipid peroxidation were investigated. Results: Our findings reveal that the SARS-CoV-2 M^pro treatment led to a concentration-dependent reduction in glucose uptake in HepG2 cells. Additionally, the M^pro treatment was associated with reduced insulin-stimulated AKT activation, particularly at higher concentrations. Inflammatory markers such as IL-6 were elevated in the extracellular medium, while DPP4 expression was decreased. However, extracellular soluble DPP4 (sDPP4) levels did not show a significant change. Despite these changes, cell viability remained relatively unaffected, suggesting that the HepG2 cells were able to maintain overall metabolic functions under M^pro exposure. Conclusions: This study demonstrated the concentration-dependent impairment of hepatic glucose metabolism, insulin signaling, and inflammatory pathways in HepG2 cells acutely exposed to the SARS-CoV-2 M^pro. These findings warrant further investigation to explore the long-term metabolic effects of SARS-CoV-2 and its proteases in the liver and to develop potential therapeutic approaches for post-viral metabolic complications. Full article

Nephronophthisis (NPH) is the leading genetic cause of end-stage renal disease in children and young adults, but no effective disease-modifying therapies are currently available. Here, we identify glucagon-like peptide-1 (GLP-1) signaling as a novel therapeutic target for NPH through a systematic drug repurposing screen in zebrafish. By simultaneously depleting nphp1 and nphp4, we developed a robust zebrafish model that reproduces key features of human NPH, including glomerular cyst formation. Our screen revealed that dipeptidyl peptidase-4 (DPP4) inhibitors (Omarigliptin and Linagliptin) and GLP-1 receptor agonists (Semaglutide) significantly reduce cystogenesis in a dose-dependent manner. Genetic analysis demonstrated that GLP-1 receptor signaling is important for maintaining pronephros integrity, with gcgra and gcgrb (GLP-1 receptor genes) playing a particularly important role. Transcriptomic profiling identified adenosine receptor A2ab (adora2ab) as a key downstream effector of GLP-1 signaling, which regulates ciliary morphology and prevents cyst formation. Notably, nphp1/nphp4 double mutant zebrafish exhibited the upregulation of gcgra as a compensatory mechanism, which might explain their resistance to cystogenesis. This compensation was disrupted by the targeted depletion of GLP-1 receptors or the inhibition of adenylate cyclase, resulting in enhanced cyst formation, specifically in the mutant background. Our findings establish a signaling cascade from GLP-1 receptors to adora2ab in terms of regulating ciliary organization and preventing cystogenesis, offering new therapeutic opportunities for NPH through the repurposing of FDA-approved medications with established safety profiles. Full article

The study aimed to evaluate how different production methods and fermentation processes using two different lactic acid bacteria (LAB) affect the chemical composition and bioactive properties of pistachio beverages. The beverages were prepared with two varieties of pistachios, one from Argentina and the other from Italy. The pistachios were processed with two technologies: a domestic processor and a colloidal mill. For the fermentation, pistachio beverages were inoculated with two different LAB strains and incubated at 28 °C for 24 h. The beverages were analyzed for proximal composition (including protein, fat, fiber, and minerals) and bioactive properties such as antioxidant activity, angiotensin-converting enzyme inhibition (ACE-I), and dipeptidyl peptidase-4 inhibition (DPP-4). The colloidal milling allowed the inclusion of the whole pistachio nut, resulting in beverages with higher solid content and no waste. Beverages treated with colloidal milling exhibited higher acidity, improved microbial fermentation performance, and generally showed higher bioactivity compared to those obtained by the domestic processor. Bioactivity varied according to the pistachio variety, the processing method and LAB strains used. Lactic acid bacteria fermentation decreased antioxidant properties of the beverages by ~40% but improved anti-hypertensive and hypoglycaemic activities. Fermented pistachio-based beverages showed promising health-promoting properties, indicating their potential as functional foods. Full article

Disorders in glucose metabolism are well-established features of polycystic ovary syndrome (PCOS) and are linked to its clinical severity and phenotypic variability. This study aimed to assess serum concentrations of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and dipeptidyl peptidase-4 (DPP-4) and to examine their relationships with glucose and insulin levels, selected sex hormone concentrations, body weight, and exposure to tobacco smoke. Women with PCOS exhibited significantly elevated levels of fasting glucose, insulin, GIP, and GLP-1 compared to controls. Tobacco smoke exposure in women with PCOS was associated with reduced DPP-4 levels, which were approximately two-fold lower in smokers than in non-smokers. A significant negative correlation between DPP-4 and cotinine levels further supported this relationship. Comorbidities such as overweight/obesity or insulin resistance (IR) were also linked to elevated incretin hormone levels. However, no significant age-related trends in incretin levels were identified, despite the known association between age and glucose dysregulation. The notable alterations in incretin hormone profiles in PCOS, along with the consistent patterns of GIP or GLP-1 with metabolic and hormonal parameters, suggest that these hormones may play coordinated regulatory roles in the pathophysiology of PCOS. Full article

Diabetic foot ulcers (DFUs), which affect approximately 15% of individuals with diabetes mellitus (DM), result from complex molecular disturbances involving chronic hyperglycemia, immune dysfunction, and infection. At the molecular level, chronic hyperglycemia promotes the formation of advanced glycation end products (AGEs), activates the AGE-RAGE-NF-κB axis, increases oxidative stress, and impairs macrophage polarization from the pro-inflammatory M1 to the reparative M2 phenotype, collectively disrupting normal wound healing processes. The local wound environment is further worsened by antibiotic-resistant polymicrobial infections, which sustain inflammatory signaling and promote extracellular matrix degradation. The rising threat of antimicrobial resistance complicates infection management even further. Recent studies emphasize that optimal glycemic control using antihyperglycemic agents such as metformin, Glucagon-like Peptide 1 receptor agonists (GLP-1 receptor agonists), and Dipeptidyl Peptidase 4 enzyme inhibitors (DPP-4 inhibitors) improves overall metabolic balance. These agents also influence angiogenesis, inflammation, and tissue regeneration through pathways including AMP-activated protein kinase (AMPK), mechanistic target of rapamycin (mTOR), and vascular endothelial growth factor (VEGF) signaling. Evidence indicates that maintaining glycemic stability through continuous glucose monitoring (CGM) and adherence to antihyperglycemic treatment enhances antibiotic effectiveness by improving immune cell function and reducing bacterial virulence. This review consolidates current molecular evidence on the combined effects of glycemic and antibiotic therapies in DFUs. It advocates for an integrated approach that addresses both metabolic and microbial factors to restore wound homeostasis and minimize the risk of severe outcomes such as amputation. Full article

Cardiovascular diseases (CVDs) are the leading cause of global mortality, with type 2 diabetes mellitus (T2DM) and obesity significantly increasing the risk of CVD. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and dipeptidyl peptidase-4 inhibitors (DPP-4is) have gained attention for their potential cardioprotective effects. Therefore, this review aims to explore the molecular mechanisms underlying the cardiovascular benefits of these agents. A literature review was conducted searching PubMed databases from 1990 to January 2025, including research on the effects of GLP-1 RA and DPP-4i on cardiovascular health, specifically concerning atherosclerosis, coronary artery disease, vascular health, cardiac arrhythmias, myocardial infarction (MI), and heart failure, with a focus on the biochemical and molecular effects of these drugs. We analyzed 131 scientific publications, which indicate that GLP-1 RA and DPP-4i significantly reduce cardiovascular risk and major adverse cardiovascular events (MACEs), including atherosclerosis, myocardial infarction, and cardiac arrhythmias. These clinical outcomes are attributed to the mitigation of oxidative stress, inflammation, and endothelial dysfunction as well as improvement in mitochondrial function and lipid metabolism. GLP-1 RAs offer substantial cardiovascular benefits, making them valuable in managing T2DM and reducing CVD risk. Their integration into treatment regimens for CVD can reduce hospitalization rates, improve quality of life, and extend life expectancy. DPP-4is, while beneficial, are less effective in cardiovascular protection. Further research is needed to optimize therapeutic strategies and broaden the clinical application of these agents in cardiometabolic care. Full article

Background: The New Zealand pine bark has been demonstrated in vitro to inhibit digestive enzymes involved in carbohydrate digestion (alpha-amylase, alpha-glucosidase, and dipeptidyl-peptidase 4 (DPP-4)). Objective: This study aims to investigate the inhibitory effects of the New Zealand pine bark on sucrose uptake and glycaemic responses in humans. Methods: A single-blind, randomised, placebo-controlled, crossover trial was carried out involving healthy adults (n = 40 (M: 12, F: 28), 30.1 ± 1.3 years, BMI 23.4 ± 0.5 kg/m², HbA1c 32.5 ± 0.6 mmol/mol, FBG 4.7 ± 0.1 mmol/L). A control (75 g of sucrose powder only), and two doses of the pine bark extract (50 and 400 mg) were provided on separate occasions, with 75 g of sucrose mixed in 250 mL of water. Blood samples were collected at −10, 0, 15, 30, 45, 60, 90, and 120 min via a finger prick test. A linear mixed model for repeated measures (SPSS v30, IBM) was applied, and data presented as model-adjusted mean ± SEM. Results: Compared to control (247.5 ± 14.0 mmol/L⋅min), the iAUCglucose was significantly reduced with the 400 mg dose (211.8 ± 13.9 mmol/L⋅min, 14.4% reduction, and p = 0.037), but not with 50 mg dose (220.8 ± 14.2 mmol/L⋅min, 10.8% reduction, and p = 0.184). Compared to control (9.1 ± 0.2 mmol/L), glucose peak value was significantly reduced with the 50 mg dose (8.6 ± 0.2 mmol/L, 5.5% reduction, and p = 0.016) but not with the 400 mg dose (8.7 ± 0.2 mmol/L, 4.4% reduction, and p = 0.093). There were no statistically significant changes in postprandial insulin levels with the pine bark extract compared to control. Conclusions: The New Zealand pine bark extract attenuated sucrose uptake with improved glycaemic responses, and may therefore be useful as a hypoglycaemic adjunct to the diet. Full article

Chicken feathers constitute a major by-product from the poultry industry, with a potential environmental impact and significant difficulties in their management. This study aimed to develop a sustainable method to hydrolyse chicken feathers and evaluate the effects of microwave (MW) irradiation pre-treatment in the generation of bioactive hydrolysates by simple or sequential hydrolysis with Alcalase. The hydrolysate with MW irradiation pre-treatment and Alcalase (2%, 2 h) (MWA) showed the highest overall antioxidant activity and neprilysin-inhibitory activity (55%), whereas samples without MW irradiation pre-treatment exerted the highest inhibitory activity of dipeptidyl peptidase IV (DPP IV) and angiotensin-converting enzyme (ACE-I), with values close to 50 and 70%, respectively. Mass spectrometry in tandem of bioactive hydrolysates was performed, and an in silico approach was used to characterise the obtained sequences. These results confirmed that MW irradiation pre-treatment improved Alcalase hydrolysis, leading to the generation of bioactive peptides with potential multifunctional properties, including antioxidant, antidiabetic, and antihypertensive activities. Moreover, this study highlights the potential of combining MW irradiation and enzymatic hydrolysis as a sustainable strategy for the revalorisation of chicken feathers. Full article

Goat caseins are highly polymorphic proteins that affect milk functional properties. In this study, an in silico approach was employed to analyze the influence of goat casein allelic variants on the quantity and bioactivity potential of peptides released after enzymatic hydrolysis. The reported protein sequences from the most frequent allelic variants in Capra hircus caseins (α-S1, β, α-S2, and κ-casein) were analyzed in the BIOPEP-UWM database to determine the frequency of occurrence of bioactive fragments from each casein. After specific hydrolysis with pepsin, trypsin, and chymotrypsin A, important differences in the peptide profile and bioactivity potential were observed within and between the casein allelic variants. The β-casein A and C alleles, α-S1-casein allele E, and α-S2-casein allele F presented the highest bioactivity potential, and some allele-specific peptides were also released, highlighting the impact of genotype on the predicted bioactivity. The inhibition of angiotensin-converting enzyme (ACE-I) and dipeptidyl peptidase IV (DPP-IV) activities was the most frequent bioactivity of the released peptides, suggesting possible antihypertensive and antidiabetic effects. Once confirmed by experimental studies, the use of goat casein genotyping could direct efforts to enhance the functional quality of goat milk. Full article

Sheep milk is a rich source of bioactive compounds with significant potential in functional foods and biomedical applications. It contains high levels of proteins, peptides, and fatty acids with numerous health-promoting properties for the human body. Key components such as lactoferrin, proline, orotic acid, and conjugated linoleic acid (CLA) support the prevention and treatment of chronic diseases such as diabetes, cardiovascular disease, obesity, cancer, and neurodegenerative disorders. Bioactive peptides from sheep milk regulate blood glucose levels by inhibiting enzymes such as dipeptidyl peptidase-IV (DPP-IV) and α-glucosidase, while conjugated linoleic acid improves lipid metabolism and reduces inflammation. The high-quality proteins in sheep milk are essential for tissue regeneration and maintaining muscle mass, which is particularly beneficial for the elderly and infants who are allergic to cow milk. Recently, there has been an increasing interest in hydrogel dressings enriched with bioactive substances from sheep milk, which support wound healing by supporting collagen synthesis, reducing inflammation, and having antimicrobial properties. Such hydrogels are particularly promising for the treatment of chronic wounds, burns, and diabetic ulcers, making them a valuable tool in regenerative medicine. The aim of this manuscript is to review the current reports on bioactive components of sheep milk and their potential for biomedical applications. Full article

The discovery of new drugs offers valuable alternatives, particularly for treating diseases that are resistant to existing therapies or involving complex, multi-organ conditions such as metabolic syndrome. Although treatment algorithms are generally well established and primarily based on synthetic pharmaceuticals, they are increasingly being supplemented by biological and biosimilar agents. This trend is particularly evident in the development and advancement of anti-diabetic and hypolipemic therapies. This review explores advances in the treatment of hypercholesterolemia and hypertriglyceridemia, elevated lipoprotein(a) [Lp(a)], diabetes, and obesity associated with metabolic syndrome. It focuses mainly on biopharmaceuticals such as proteins and nucleotide-based drugs (antisense oligonucleotides, small interfering RNA), but also on dipeptidyl peptidase-4 (DPP-4) inhibitors classified as incretin drugs along with glucagon-like peptide-1 (GLP-1) analogues. Due to the substantial role of SGLT-2 (sodium/glucose cotransporter 2) inhibitors in novel diabetes therapies, especially for managing cardiovascular risk, this group of compounds was also included in this review. Many clinical data in the field of effectiveness of biopharmaceuticals in metabolic disorders are provided. Therefore, in this review, we mainly include a brief history of drug development and approval, first synthesis and structure modifications, which relevantly influence pharmacokinetics, and safety. We provide only brief comparison of biological drugs with metformin and sulphonylureas derivatives. Databases such as PubMed, Scopus, and Google Scholar are searched for the period between 2000 and 2024. Full article