One of the possible candidates for the treatment of diabetic cardiomyopathy is liraglutide, a glucagon-like peptide-1 receptor (GLP1R) agonist. In this study, the impacts of liraglutide on the integrin-linked kinase (ILK)-related PI3K/AKT axis in rats with type 2 diabetes induced via streptozotocin were examined. Twenty-four Wistar albino rats were distributed in four different groups, and a high-fat diet and streptozotocin were used to induce type 2 in two groups. Rats in the untreated control groups were administered 0.9% NaCl solution over a 6-week period, and those in the treatment groups were administered 0.9% NaCl for 3 weeks, followed by subcutaneous injection of liraglutide (150 μg/kg) for an additional 3 weeks. In the liraglutide-treated diabetic group, the heart-to-body weight ratio was significantly reduced, levels of cardiac biomarkers, troponin I and creatine-kinase-MB, were improved; activities of antioxidant enzymes, glutathione peroxidase and superoxide dismutase, were increased; and levels of malondialdehyde were decreased. Western blotting and immunohistochemical studies revealed increased levels of ILK, P-PI3K, P-AKT, and BCL2, as well as those of caspase 3, BAX, and P-PTEN, indicating mitigation of cardiomyocyte apoptosis. Our results show that liraglutide, by targeting GLP1Rs, enhances the expression of proteins in the ILK/PI3K/AKT/PTEN pathway and thereby exerts its cardioprotective effects in rats with DCM.

Cellular senescence is a hallmark of aging and contributes to age-related diseases, including diabetic nephropathy (DN). Additionally, macrophage-mediated inflammation has been linked with DKD. Therefore, we investigated the effect of macrophage depletion on kidney cell senescence in DN, focusing on the relationship between the GDF-15 and Klotho signaling pathways. Wistar albino rats (n = 24) were divided into four groups: healthy control, liposomal clodronate (LC)-treated healthy, diabetic, and LC-treated diabetic groups. Rats in the LC-treated healthy, diabetic, and LC-treated diabetic groups were intravenously administered LC once a week for 4 weeks. Rat models of type 2 diabetes were successfully established via the administration of streptozotocin and a high-fat diet, as evidenced by increased blood glucose levels, kidney weight to body weight (KW/BW) ratio, serum albumin, creatinine, and urea levels, kidney damage, and oxidative stress. However, LC-mediated macrophage depletion reduced the KW/BW ratio, improved serum and oxidative parameters, decreased inflammatory markers (IL-6 and TNF-α), and ameliorated oxidative stress. Additionally, LC treatment promoted macrophage polarization towards the anti-inflammatory phenotype, downregulated GDF-15 expression, upregulated Klotho expression, and ameliorated kidney damage. In conclusion, macrophage depletion combats kidney senescence by modulating Klotho and GDF-15, indicating their potential as novel targets in DN treatment.

Background: Diabetic nephropathy (DN) accelerates renal aging through chronic inflammation and metabolic dysregulation; however, the role of metformin in this process remains incompletely understood. This study investigated whether metformin attenuates diabetes-driven renal senescence through the modulation of the fatty acid-binding protein 4 (FABP4)/forkhead box protein O1 (FOXO1) axis and key immunometabolic enzymes. Methods: Thirty-two male Wistar rats were divided into healthy and diabetic groups and treated with either saline or metformin (200 mg/kg) for 10 weeks. Type 2 diabetes was induced by multiple low doses of streptozotocin (30 mg/kg, intraperitoneally) and high-fat diet. Renal function indices, lipid profile, inflammatory cytokines, succinate dehydrogenase (SDH), ATP-citrate lyase (ACLY), and senescence markers were measured, while FABP4 and FOXO1 expression, macrophage infiltration, and kidney histology were assessed using immunoassays and microscopy. Results: Metformin considerably reduced serum creatinine, urea, and blood urea nitrogen; normalized the lipid profile; suppressed interleukin (IL)-6 and tumor necrosis factor-α; and increased IL-10 levels. Additionally, it reversed DN-associated alterations in SDH and ACLY; downregulated FABP4, FOXO1, and P16^INK4a; decreased macrophage infiltration; promoted M2 polarization; and improved renal architecture. Conclusions: This study is the first to demonstrate that metformin mitigates diabetic renal senescence by simultaneously targeting the FABP4/FOXO1 axis and immunometabolic enzymes SDH and ACLY. These findings highlight the translational significance of metformin as a prototype for immunometabolic and immunosenescence-directed therapies in DN.

Background/Objectives: Cardiovascular disease increases with ageing and remains the leading cause of death worldwide. Cellular senescence contributes to cardiac dysfunction in the older population by secreting the senescence-associated secretory phenotype (SASP). Cardiac injury models induced by surgery have been shown to induce senescence in young adult rodents. However, surgical models are complex and associated with high mortality. Methods: We established a rat model of injury and senescence using isoproterenol (ISO). Male SD rats received ISO (100 mg/kg) for five days, then hearts were collected on days 10 and 28 after the first ISO dose. Results: ISO administration caused cardiac injury, manifested by inflammatory infiltration, fibrosis, and increased cardiomyocyte cross-sectional area. Cardiac injury was accompanied by an increase in the senescence markers SA-β-gal, p16 and p21, and DNA damage marker γH2AX. Moreover, the mRNA levels of p21 increased on day 10, along with several SASP factors, whereas the mRNA levels of p16 increased on day 28. Fibrosis, hypertrophy, and senescence persisted until day 28, indicating long-lasting cardiac remodeling and senescent cell accumulation. Conclusions: These findings suggest that ISO can provide a simple, cost-effective platform for studying senescence and cardiac injury. This model facilitates the study of timing, dosage, mechanisms and efficacy of senolytic interventions and may contribute to the development of senescence-targeted therapies.

Background: Opioid use disorder (OUD) remains a critical global health challenge, with highly potent synthetic opioids like fentanyl contributing to overdose deaths. The available treatments have limitations. The endocannabinoid system has emerged steadily as a therapeutic target for the opioid crisis due to its modulatory effects on opioid reward and withdrawal and its involvement in regulating inflammation. These studies investigate the potential of cannabidiol (CBD) and its synthetic derivative (L-1β IN-1) in mitigating fentanyl effects. Methods: C57BL/6 male mice were used in several behavioral assays: two-bottle choice (TBC) to measure fentanyl reward/seeking behaviors, hot plate to assess antinociception, and marble burying to evaluate compulsive/adverse effects. Additionally, a neurometabolic study was conducted to evaluate the impact of chronic high doses of fentanyl alone and in combination with CBD or L-1β-IN-1 on brain metabolic signatures. Results: The mice consistently preferred to drink fentanyl, and i.p. injections of 10 mg/kg CBD or 5–25 mg/kg of L-1β-IN-1 decreased the fentanyl preference scores to values below 0.5. The antinociceptive effects of pretreatment groups showed a trend of enhanced analgesic effects in the hot plate assay. However, they showed no significant changes in the marble-burying assay, suggesting that pretreatment with these compounds lacks acute stereotypic effects. The Fentanyl metabolomics revealed robust metabolic activation with fentanyl alone, while CBD or L-1β-IN-1 showed different profiles in modulating these fentanyl-induced metabolic signatures. Conclusions: These studies provide evidence about the in vivo behavioral and neurometabolic profiles of fentanyl after pretreatment with CBD and synthetic CBD, presenting them as possible pharmacological tools for OUD research.