Protective effects of GLP-1 on glomerular endothelium and its inhibition by PKCβ activation in diabetes

Effects of oral antidiabetic agents on the renin-angiotensin-aldosterone system

BACKGROUND

The renin-angiotensin-aldosterone system (RAAS) is a vital endocrine system that plays a crucial role in maintaining homeostasis. However, excessive activation of the RAAS can contribute to the pathogenesis of certain diseases. Prolonged hyperglycemia leads to overactivation of the RAAS through the production of inflammatory factors and other mechanisms, ultimately resulting in diabetic complications. Oral antidiabetic agents are the cornerstone of diabetes treatment, and the effects of oral antidiabetic agents on the RAAS have not been clearly summarized.

OBJECTIVE

To review the effects of various types of oral antidiabetic agents on the components of the RAAS.

RESULTS

Sodium-glucose cotransporter inhibitors (SGLT2i) inhibit glucose and sodium reabsorption, which increases the flow of Na+ to the macula densa, thereby inhibiting tubuloglomerular feedback (TGF) and subsequently decreasing renin production. GLP-1 receptor agonists (GLP-1RA) and dipeptidyl peptidase-4 inhibitors (DPP-4i) can directly inhibit angiotensin II (Ang II) or indirectly suppress it by modulating TGF. These agents also affect Ang II type 1 receptors (AT1R) and Ang II type 2 receptors (AT2R) to mitigate Ang II and can indirectly interact with Ang II through Na+/H+ exchanger isotope 3 (NHE3). Thiazolidinediones (TZDs), as PPAR-γ agonists, can enhance the expression of the renin gene, inhibit the production of angiotensin-converting enzyme (ACE), regulate the levels of AT1R and AT2R, and decrease aldosterone production. Metformin also inhibits the production of renin and aldosterone in patients with polycystic ovary syndrome (PCOS).

CONCLUSIONS

These oral agents, which exhibit diverse effects on the components of the RAAS, modulate the activity of these components to exert antihypertensive, anti-inflammatory, cardioprotective, and renoprotective effects, thereby offering several beneficial outcomes in the management of diabetes.

Renoprotective mechanisms of glucagon-like peptide-1 receptor agonists

Glucagon-like peptide-1 (GLP-1) is an incretin hormone, secreted from gut endocrine cells, which acts to potentiate nutrient-induced insulin secretion. Activation of its receptor, GLP-1R, decreases glucagon secretion and gastric emptying, thereby decreasing blood glucose and body weight. It is largely through these mechanisms that Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have transformed the treatment of type 2 diabetes. More recently, preclinical and clinical studies have reported that these agents have potent extra-pancreatic effects, exhibiting cardioprotective and renoprotective actions. The recent FLOW trial was the first multicentre clinical trial investigating the effect of GLP-1RAs on a primary renal outcome and reported robust evidence that GLP-1RAs are renoprotective. Studies in rodent models of renal injury have shown that gain and loss of GLP-1R signalling improves or deteriorates kidney function. However, the precise mechanisms responsible for renal benefits of GLP-1RAs are not yet fully understood. While prolonged activation of GLP-1 receptors (GLP-1R) has been shown to reverse diabetes-related disruptions in gene expression across various renal cell populations, GLP-1R expression in both rodent and human kidneys is thought to be primarily confined to certain vascular smooth muscle cells. This review discusses recent advances in our understanding of the effects of GLP-1 medicines on the kidney with a focus on indirect and direct mechanisms of action.

Endothelin receptor antagonists for diabetic kidney disease: back to the future?

INTRODUCTION

Diabetic kidney disease (DKD) is a leading cause of chronic kidney disease worldwide. Endothelin-1 (ET-1) is a potent vasoconstrictor secreted by vascular endothelial cells, actively involved in the pathophysiology of numerous cardiovascular diseases. Based on the differential downstream effects of ET-1 binding to its two distinct types of receptors (ETA/ETB) within the kidney, selective ETA receptor blockade has been long proposed as a promising treatment modality for DKD.

AREAS COVERED

This review aims to examine the available evidence base for the use of ERAs in the treatment of DKD, by critically reappraising available landmark trials and discussing their possible position in the context of current treatment of this disease.

EXPERT OPINION

Despite early enthusiasm and widespread expectations, endothelin receptor antagonists (ERAs) faded into obscurity following the release of the first randomized controlled trials (RCTs). More recent RCTs using different compounds have re-introduced ERAs as a promising treatment in the growing pharmaceutical armamentarium of DKD. While the future of DKD management will be based on a more personalized approach, new, robust evidence from appropriately designed RCTs is eagerly anticipated to clearly define the role of ERAs in DKD.

Control of Mitochondrial Quality: A Promising Target for Diabetic Kidney Disease Treatment

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD), affecting over 40% of patients with diabetes. DKD progression involves fibrosis and damage to glomerular and tubulointerstitial regions, with mitochondrial dysfunction playing a critical role. Impaired mitochondria lead to reduced adenosine triphosphate (ATP) production, damaged mitochondria accumulation, and increased reactive oxygen species (ROS), contributing to renal deterioration. Maintaining mitochondrial quality control (MQC) is essential for preventing cell death, tissue injury, and kidney failure. Recent clinical trials show that enhancing MQC can alleviate DKD. However, current treatments cannot halt kidney function decline, underscoring the need for new therapeutic strategies. Mitochondrial-targeted drugs show potential; however, challenges remain because of adverse effects and unclear mechanisms. Future research should aim to comprehensively explore therapeutic potential of MQC in DKD. This review highlights the significance of MQC in DKD treatment, emphasizing the need to maintain mitochondrial quality for developing new therapies.

Effects of Novel Antidiabetic Agents on Contrast-Associated Acute Kidney Injury in Diabetic Patients Undergoing Percutaneous Coronary Intervention

Contrast-associated acute kidney injury (CA-AKI) remains a serious complication after percutaneous coronary revascularization (PCI), with limited effective preventive strategies especially for diabetic patients. This study aimed to assess the effects of novel antidiabetic agents (NAD), i.e., glucagon-like peptide-1 receptor agonists (GLP-1RAs), sodium-glucose transporter-2 inhibitors (SGLT2i), and dipeptidyl peptidase-4 inhibitors (DPP4i), on the occurrence of this outcome in diabetic patients undergoing PCI. We enrolled 293 consecutive diabetic patients receiving NAD at the time of PCI (NAD group) and paired them with 293 diabetic individuals undergoing revascularization who were not on NAD (no-NAD group), matched according to age and sex. CA-AKI was defined as an increase in serum creatinine (SCr) ≥0.3 mg/dl or >50% from baseline within 48 to 72 hours after contrast exposure. A propensity score-adjusted logistic regression analysis was performed to account for potential selection bias. NAD treatment was associated with a significantly reduced incidence of CA-AKI than standard glucose-lowering therapies (4.1 vs. 8.5%, p = 0.023). Furthermore, patients using SGLT2i and GLP-1RAs exhibited a lower incidence of CA-AKI compared to those taking DPP4i. Both multivariate and propensity-score-adjusted regression analyses identified NAD therapy as an independent predictor of CA-AKI (OR 0.45, 95% CI 0.22-0.98, p = 0.040 and OR 0.48, 95% CI 0.23-0.98, p = 0.045). In conclusion, this study is the first to explore the potential benefit of all three NAD classes on CA-AKI incidence. The use of these agents is associated with a lower incidence of renal damage in diabetic patients undergoing PCI, with the greatest benefit observed with SGLT2i and GLP-1RAs use.

MiR-203 improved renal cell injury in diabetic nephropathy by targeting SOCS6/SOCS7 and inhibiting JAK/STAT pathway activation

This study investigates the role of miR-203 in regulating renal cell injury in diabetic nephropathy by targeting the suppressor of cytokine signaling (SOCS) proteins SOCS6 and SOCS7. Using NRK cells, we assessed apoptosis through flow cytometry and TUNEL assays, while real-time quantitative PCR (RT-PCR) quantified miRNA and mRNA expressions. Cell viability was measured using the CCK-8 assay, and cytokine levels were determined through ELISA. We also evaluated reactive oxygen species (ROS) and malondialdehyde (MDA) levels with specific assay kits. The dual luciferase assay confirmed the interaction of miR-203 with SOCS6 and SOCS7. Western blotting analyzed the protein levels of key signaling molecules including JAK1, p-JAK1, JAK2, p-JAK2, STAT3, and p-STAT3.Our findings revealed that high glucose (HG) treatment reduced miR-203 levels, leading to decreased NRK cell proliferation, increased cytokine concentrations (TNF-α, IL-1β, IL-4, IL-6), heightened ROS and MDA levels, and increased cell apoptosis. Notably, miR-203 mimics counteracted HG's detrimental effects, while miR-203 inhibitors exacerbated them. Mechanistically, miR-203 directly decreased SOCS6 and SOCS7 expression, thereby inhibiting JAK/STAT3 signaling. Thus, miR-203 provides protective effects against renal cell injury by modulating SOCS and their associated pathways.

Exploring factors predicting the effectiveness of oral semaglutide in Japanese individuals with type 2 diabetes switching from dipeptidyl peptidase 4 inhibitors: a pilot study

Introduction

Oral semaglutide is a glucagon-like peptide-1 receptor agonist (GLP-1 RA) approved for the treatment of type 2 diabetes mellitus (T2DM). Findings from randomized controlled trials (RCTs) and real-world studies indicate that oral semaglutide leads to significant improvements in HbA1c and body weight, comparable to those observed with injectable GLP-1 RAs. Consequently, oral semaglutide is expected to significantly reduce barriers to initiating GLP-1 RA therapy in individuals with diabetes and may lead to an increased transition from dipeptidyl peptidase-4 inhibitors (DPP-4is) to GLP-1 RA therapy. This study was conducted to prospectively investigate the clinical characteristics predicting the achievement of HbA1c < 7% (52 mmol/mol) in Japanese individuals with T2DM who switched from DPP-4is to oral semaglutide.

Methods

The study enrolled a total of 74 patients who switched from DPP-4is to oral semaglutide between December 2021 and October 2022, with the dose being uptitrated to achieve HbA1c < 7% (52 mmol/mol) in these patients.

Results

The study included a total of 44 individuals who achieved the target with oral semaglutide 3 mg (n=7), 7 mg (n=24), or 14 mg (n=13), and 17 individuals who did not (un-achieved group; n=17), based on their clinical characteristics and hematological findings. In the comparison between the Un-achieved group and the Achieved (3 to 14 mg) group, the proportions of "Current alcohol drinking (p = 0.030)" and "Current alcohol drinking and smoking (p = 0.029)" were higher in the Un-achieved group, whereas the proportion of "Taking 31 minutes or longer to have breakfast after drug administration (p = 0.022)" was higher in the Achieved (3 to 14 mg) group. A logistic regression analysis using the stepwise method identified "No current history of both smoking and alcohol drinking (0.083[0.014-0.485]; p = 0.006)" and "Taking 31 minutes or longer to eat breakfast after drug administration (0.117[0.029-0.480]; p = 0.003)" as factors predicting the achievement of the HbA1c < 7% (52 mmol/mol).

Conclusion

Study findings suggest when considering switching T2D patients from DPP-4is to oral semaglutide, a detailed assessment of "current alcohol drinking and smoking status" and "the duration between the administration of oral semaglutide and breakfast" may be useful as a predictive indicator for achieving HbA1c < 7% (52 mmol/mol).

Inappropriate diet and hygiene status affect the progression of diabetic kidney disease by causing dysbiosis

OBJECTIVE

Although the effects of an unhealthy diet on the risks of diabetes and its renal complications are well understood, the effects of hygiene status have not been fully elucidated.

RESEARCH METHODS AND PROCEDURES

We created four groups of mice according to the diet fed (standard [SD] or high-fat [HFD]) and their living environment (conventional [CV] or specific pathogen-free [SPF]), and characterized the extent of their kidney pathology, their gut microbiota, and their fecal short-chain fatty acid (SCFA) concentrations.

RESULTS

The body masses and glycated hemoglobin levels of the HFD and CV groups were significantly higher than those of the SD and SPF groups, respectively. The renal mRNA expression of markers of inflammation and fibrosis and the protein level of CD31 were higher in the HFD and CV groups than in the SD and SPF groups, respectively. Although the alpha diversities and total SCFA concentrations of the HFD and CV groups were significantly lower than those of the SD and SPF groups, respectively, the mRNA expression of genes involved in inflammation, innate immunity, tight junctions, and glucose transporters in the gut was only affected by HFD.

CONCLUSIONS

Gut microbial dysbiosis, owing to the combined effects of inappropriate diet and excessive hygiene, accompanied by lower intestinal SCFA production, may contribute to the development and/or progression of diabetes and diabetic kidney disease through the induction of inflammation and fibrosis.

Association of glucagon-like peptide-1 receptor agonists with cardiovascular and kidney outcomes in type 2 diabetic kidney transplant recipients

BACKGROUND

Cardiovascular disease is a leading cause of post-transplant mortality in kidney transplant recipients (KTRs), especially those with diabetes. Although glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have demonstrated cardiovascular and kidney benefits in the general population with type 2 diabetes mellitus (T2DM), evidence regarding their effects in diabetic KTRs is limited.

METHODS

This retrospective cohort study utilized data from the Global Collaborative Network in TriNetX, spanning January 1, 2006, to June 1, 2023. Propensity score matching (PSM) with 1:1 ratio was employed to create balanced cohorts. Adult KTRs with T2DM who received GLP-1 RAs within 3 months post-transplant were compared to a matched cohort of KTRs who did not. The primary outcome was all-cause mortality, with secondary outcomes including major adverse cardiovascular events (MACEs) and major adverse kidney events (MAKEs).

RESULTS

A total of 35,488 adult KTRs with T2DM (mean [SD] age, 57.7 [12.2] years; 57.7% men) were identified and 9.8% patients used GLP-1 RAs among 3 months post-transplant. Following PSM, 3564 GLP-1 RAs users were matched with an equal number of nonusers. After a median follow-up of 2.5 years, GLP-1 RAs users had lower risks of mortality (adjusted hazard ratio (aHR), 0.39; 95% CI 0.31-0.50), MACEs (aHR 0.66; 95% CI 0.56-0.79), and MAKEs (aHR 0.66; 95% CI 0.58-0.75). Adverse effects included higher risks of nausea, vomiting and diarrhea, while risks of suicide, hypoglycemia, retinopathy, and pancreatitis were not increased.

CONCLUSIONS

In KTRs with T2DM, GLP-1 RAs use was associated with substantial reductions in all-cause mortality, MAKEs, and MACEs compared to nonuse without increasing complications. However, the underutilization of GLP-1 RAs represents a significant opportunity to improve post-transplant outcomes in this high-risk population.

Non-linear relationship between urinary creatinine and diabetic kidney disease: implications for clinical practice

OBJECTIVE

This study aims to investigate the relationship between urinary creatinine (UCr) and the risk and severity of Diabetic Kidney Disease (DKD) in patients with Type 2 Diabetes Mellitus (T2DM). The goal is to establish UCr as a potential biomarker for early DKD detection and severity assessment.

METHODS

A retrospective cross-sectional analysis was conducted using medical records of T2DM patients. Patients were classified into groups with and without DKD, and relevant clinical data, including demographic, blood, and urine parameters, were collected. Logistic regression and receiver operating characteristic (ROC) curve analysis evaluated the association between UCr levels and DKD. Curve fitting and threshold effect model were used to further evaluate the relationship between UCr and the incidence and severity of DKD.

RESULTS

A total of 302 T2DM patients were analyzed, with 137 diagnosed with DKD. Significant differences in clinical parameters were observed between the DKD and non-DKD groups, particularly in UCr, urine albumin levels, and eGFR. UCr levels demonstrated a strong association with DKD. Moreover, a non-linear relationship was identified, with specific inflection points indicating different correlation patterns of UCr with DKD occurrence and progression.

CONCLUSION

The findings of this study highlight the potential of UCr as a valuable biomarker for early detection and assessment of DKD in T2DM patients. Incorporating UCr measurements into routine clinical practice could enhance early identification of patients at risk for kidney complications, leading to timely intervention and improved patient outcomes.

Exploring Liraglutide's mechanism in reducing renal fibrosis: the Fsp1-CoQ10-NAD(P)H pathway

Studies have confirmed that elevated glucose levels could lead to renal fibrosis through the process of ferroptosis. Liraglutide, a human glucagon-like peptide-1 (GLP-1) analogue, is a potential treatment option for diabetes. This study aimed to examine the potential of liraglutide (LIRA) in inhibiting ferroptosis and reducing high glucose-induced renal fibrotic injury in mice, and whether the Fsp1-CoQ10-NAD(P)H signal pathway is a mechanism for this effect. In our study, we used db/db mice to simulate Type 2 diabetes mellitus (T2DM). The mice were intraperitoneally injected with LIRA (200 µg/kg/d) daily for 6 weeks. Renal function, pathologic changes, lipid peroxidation levels, iron levels, and ferroptosis were assessed. First, LIRA ameliorated renal dysfunction and fibrosis in db/db mice. Second, LIRA inhibited lipid peroxidation by up-regulating T-SOD, GSH-Px, and GSH activities as well as down-regulating the levels of 8-OHDG, MDA, LPO, 4-HNE, 12-Lox, and NOX4 in db/db mice. In addition, LIRA attenuated iron deposition by decreasing the expression of TfR1 and increasing the expression of FPN1. Meanwhile, LIRA reduced high levels of high glucose-induced cell viability decline and intracellular lipid peroxidation. Furthermore, LIRA inhibited ferroptosis by adjusting the Fsp1-CoQ10-NAD(P)H pathway in vivo and in vitro. These findings suggested that LIRA attenuated kidney fibrosis injury in db/db mice by inhibiting ferroptosis through the Fsp1-CoQ10-NAD(P)H pathway.

Kidney effects of Glucagon-Like Peptide 1 (GLP1): from molecular foundations to a pharmacophysiological perspective

GLP1 receptor agonists (GLP1-RAs) are drugs that mimic the effects of the incretin hormone GLP1 and were initially introduced in medicine for the treatment of diabetes in 2005 and for obesity in 2014. Over time, data from secondary and exploratory objectives of large randomized controlled-trials suggested that GLP1-RAs could also exert renal action by slowing the progression of kidney disease in patients with and without diabetes. Based on this rationale, the Flow study (1 mg semaglutide vs placebo) was designed and recruitment began in 2019 until May 2021. The recently published results confirmed the effect of semaglutide in reducing the composite renal outcome. However, similar to SGLT2 inhibitors, the potential mechanisms behind the renal effects of GLP1-RAs still need to be elucidated. The aim of this review is to address the different physiological mechanisms of GLP1-RAs at the renal level, using evidence from experimental studies and current scientific literature.

One anastomosis gastric bypass ameliorates diabetic nephropathy via regulating the GLP-1-mediated Sirt1/AMPK/PGC1α pathway

BACKGROUND

Diabetic nephropathy (DN), a complication of diabetes, is the most leading cause of end-stage renal disease. Bariatric surgery functions on the remission of diabetes and diabetes-related complications. One anastomosis gastric bypass (OAGB), one of popular bariatric surgery, can improve diabetes and its complications by regulating the glucagon-like peptide-1 (GLP-1) level. Meanwhile, GLP-1 can alleviate renal damage in high-fat-diet-induced obese rats. However, the effect of OAGB on renal injury remains uncertain in DN.

METHODS

A diabetes model was elicited in rats via HFD feeding and STZ injection. The role and mechanism of OAGB were addressed in DN rats by the body and kidney weight and blood glucose supervision, oral glucose tolerance test (OGTT), enzyme-linked immunosorbent assay (ELISA), biochemistry detection, histopathological analysis, and western blot assays.

RESULTS

OAGB surgery reversed the increase in body weight and glucose tolerance indicators in diabetes rats. Also, OAGB operation neutralized the DN-induced average kidney weight, kidney weight/body weight, and renal injury indexes accompanied with reduced glomerular hypertrophy, alleviated mesangial dilation and decreased tubular and periglomerular collagen deposition. In addition, OAGB introduction reduced the DN-induced renal triglyceride and renal cholesterol with the regulation of fatty acids-related proteins expression. Mechanically, OAGB administration rescued the DN-induced expression of Sirt1/AMPK/PGC1α pathway mediated by GLP-1. Pharmacological block of GLP-1 receptor inverted the effect of OAGB operation on body weight, glucose tolerance, renal tissue damage, and fibrosis and lipids accumulation in DN rats.

CONCLUSION

OAGB improved renal damage and fibrosis and lipids accumulation in DN rats by GLP-1-mediated Sirt1/AMPK/PGC1α pathway.

New Insights into the Pleiotropic Actions of Dipeptidyl Peptidase-4 Inhibitors Beyond Glycaemic Control

Dipeptidyl peptidase-4 (DPP-4) is a multifunctional serine ectopeptidase that cleaves and modifies a plethora of substrates, including regulatory peptides, cytokines and chemokines. DPP-4 is implicated in the regulation of immune response, viral entry, cellular adhesion, metastasis and chemotaxis. Regarding its numerous substrates and extensive expression inside the body, multitasking DPP-4 has been assumed to participate in different pathophysiological mechanisms. DPP-4 inhibitors or gliptins are increasingly used for the treatment of type 2 diabetes mellitus. Several reports from experimental and clinical studies have clarified that DPP-4 inhibitors exert many beneficial pleiotropic effects beyond glycaemic control, which are mediated by anti-inflammatory, anti-oxidant, anti-fibrotic and anti-apoptotic actions. The present review will highlight the most recent findings in the literature about these pleiotropic effects and the potential mechanisms underlying these benefits, with a specific focus on the potential effectiveness of DPP-4 inhibitors in coronavirus disease-19 and diabetic kidney disease.

Emerging therapeutic landscape: Incretin agonists in chronic kidney disease management

The increasing incidence of chronic kidney disease (CKD) poses a significant public health concern, prompting heightened attention to its treatment. Incretins, including glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide, are intestinal peptides released after nutrient intake, known for their hypoglycemic effects in diabetes management. Recent advancements highlight the promising outcomes of GLP-1 receptor agonists in reducing CKD risk factors and improving renal outcomes. The multifaceted functions of GLP-1, such as its anti-obesity, anti-hypertensive, anti-hyperglycemic, anti-lipid, anti-inflammatory, and endothelial function protective properties, contribute to its potential as a therapeutic agent for CKD. Although experiments suggest the potential benefits of incretin in CKD, a comprehensive understanding of its specific mechanisms is still lacking. This review aims to provide a detailed examination of current evidence and potential future directions, emphasizing the promising yet evolving landscape of incretin agonists in the context of CKD.

Sodium butyrate improves renal injury in diabetic nephropathy through AMPK/SIRT1/PGC-1α signaling pathway

Diabetic nephropathy (DN) is a prototypical chronic energy metabolism imbalance disease. The AMPK/Sirt1/PGC-1α signaling pathway plays a pivotal role in regulating energy metabolism throughout the body. Gut microbiota ferment indigestible carbohydrates to produce a variety of metabolites, particularly short-chain fatty acids (SCFAs), which exert positive effects on energy metabolism. However, the potential for SCFAs to ameliorate DN-associated renal injury via the AMPK/Sirt1/PGC-1α pathway remains a matter of debate. In this study, we investigated the effects of sodium butyrate (NaB), a SCFA, on energy metabolism in mice with spontaneous DN at two different doses. Body weight, blood glucose and lipid levels, urinary protein excretion, liver and kidney function, interleukin-6 (IL-6) levels, and the expressions of AMPK, phosphorylated AMPK (p-AMPK), mitofusin 2 (MFN2), optic atrophy 1 (OPA1), and glucagon-like peptide-1 receptor (GLP-1R) were monitored in mice. Additionally, butyrate levels, gut microbiota composition, and diversity in colonic stool were also assessed. Our findings demonstrate that exogenous NaB supplementation can improve hyperglycemia and albuminuria, reduce renal tissue inflammation, inhibit extracellular matrix accumulation and glomerular hypertrophy, and could alter the gut microbiota composition in DN. Furthermore, NaB was found to upregulate the expressions of MFN2, OPA1, p-AMPK, and GLP-1R in DN renal tissue. These results suggest that NaB could improve the composition of gut microbiota in DN, activate the AMPK/Sirt1/PGC-1α signaling pathway, and enhance mitochondrial function to regulate energy metabolism throughout the body. Collectively, our findings indicate that NaB may be a novel therapeutic agent for the treatment of DN.

The role of glucagon-like peptide-1/GLP-1R and autophagy in diabetic cardiovascular disease

Diabetes leads to a significantly accelerated incidence of various related macrovascular complications, including peripheral vascular disease and cardiovascular disease (the most common cause of mortality in diabetes), as well as microvascular complications such as kidney disease and retinopathy. Endothelial dysfunction is the main pathogenic event of diabetes-related vascular disease at the earliest stage of vascular injury. Understanding the molecular processes involved in the development of diabetes and its debilitating vascular complications might bring up more effective and specific clinical therapies. Long-acting glucagon-like peptide (GLP)-1 analogs are currently available in treating diabetes with widely established safety and extensively evaluated efficacy. In recent years, autophagy, as a critical lysosome-dependent self-degradative process to maintain homeostasis, has been shown to be involved in the vascular endothelium damage in diabetes. In this review, the GLP-1/GLP-1R system implicated in diabetic endothelial dysfunction and related autophagy mechanism underlying the pathogenesis of diabetic vascular complications are briefly presented. This review also highlights a possible crosstalk between autophagy and the GLP-1/GLP-1R axis in the treatment of diabetic angiopathy.

Exendin-4, a glucagon-like peptide-1 receptor agonist, alleviates muscular dysfunction and wasting in a streptozotocin-induced diabetic mouse model compared to metformin

Diabetic muscular atrophy is becoming a fast-growing problem worldwide, including sarcopenia, which is associated with substantial mortality and morbidity risk. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been marketed and suggested to exert protective effects on not only glycemic control but also diabetic complications in diabetic patients. In this study, we investigated the therapeutic use of GLP-1RAs exendin-4, compared to antidiabetic drug metformin, for the intervention of muscular dysfunction during diabetic conditions using a streptozotocin (STZ)-induced diabetic mouse model. The results showed that both exendin-4 and metformin could effectively alleviate hyperglycemia in diabetic mice, and also counteract diabetes-induced muscle weight loss, weaker grip, and changes in muscle fiber cross-sectional area distribution. Unexpectedly, exendin-4, but not metformin, enhanced the increased kidney weight and histological change in diabetic mice. Taken together, these findings suggest that both exendin-4 and metformin could effectively improve the diabetic hyperglycemia and muscular dysfunction; but exendin-4 may aggravate the nephropathy in STZ-induced diabetic mice.

Chronic kidney disease combined with metabolic syndrome is a non-negligible risk factor

Metabolic syndrome (MetS) is a group of conditions characterized by hypertension (HTN), hyperglycaemia or insulin resistance (IR), hyperlipidaemia, and abdominal obesity. MetS is associated with a high incidence of cardiovascular events and mortality and is an independent risk factor for chronic kidney disease (CKD). MetS can cause CKD or accelerate the progression of kidney disease. Recent studies have found that MetS and kidney disease have a cause-and-effect relationship. Patients with CKD, those undergoing kidney transplantation, or kidney donors have a significantly higher risk of developing MetS than normal people. The present study reviewed the possible mechanisms of MetS in patients with CKD, including the disorders of glucose and fat metabolism after kidney injury, IR, HTN and the administration of glucocorticoid and calcineurin inhibitors. In addition, this study reviewed the effect of MetS in patients with CKD on important target organs such as the kidney, heart, brain and blood vessels, and the treatment and prevention of CKD combined with MetS. The study aims to provide strategies for the diagnosis, treatment and prevention of CKD in patients with MetS.

Efficacy and Safety of Vildagliptin for Type 2 Diabetes in Patients With Diabetic Kidney Disease

BACKGROUND/AIM

Vildagliptin is one of the dipeptidyl peptidase-4 (DPP-4) inhibitors that have been shown to improve hyperglycemia in clinical trials among patients with type 2 diabetes. However, few studies have examined the efficacy of vildagliptin in patients with diabetic kidney disease (DKD).

PATIENTS AND METHODS

Eight patients with DKD received oral vildagliptin 50-100 mg/day. The duration of diabetes was 6.7±5.9 years and observation period was 23.6±9.8 months. Changes in fasting blood glucose, and hemoglobin A1c (HbA1c), estimated glomerular filtration rate (eGFR), and urine protein-to-creatinine ratio (UPCR) were studied before and after the administration of vildagliptin.

RESULTS

Vildagliptin treatment significantly decreased fasting blood glucose and HbA1c, compared to baseline (132±56 mg/dl, p=0.036, 6.0±0.3, p=0.041, respectively). UPCR tended to be decreased, albeit without statistical significance. However, eGFR was decreased after the administration of vildagliptin. No significant adverse effects were observed in all patients during the study.

CONCLUSION

Although the sample size was limited and the observation period was brief, vildagliptin was found to be an effective and reasonably well-tolerated treatment for patients with DKD.

Plasma Asprosin Concentrations are Associated with Progression of Diabetic Kidney Disease

Purpose

To explore the expression of asprosin in subjects with pre-DKD and DKD and to analyze its relationship with kidney injury, inflammation, and glucose and lipid metabolism.

Methods

Based on urine albumin:creatinine ratio (UACr), participants were divided into DM, pre-DKD, and DKD groups. Relevant human physiological and biochemical parameters were detected in the three groups.

Results

We found relatively higher levels of asprosin in both pre-DKD and DKD groups than the DM group. Moreover, data from the Nephroseq database support increased gene expression of asprosin in kidney tissue from DKD patients. Further correlation analysis revealed that the plasma asprosin level was positively correlated with age, waist circumference, waist:hip ratio, systolic blood pressure, creatinine, UACr, triglycerides, HDL-c, fasting insulin, HOMA-IR, and the inflammatory marker G3P and negatively associated with eGFR. Multiple logistical regression analysis showed that asprosin concentration was significantly associated with pre-DKD and DKD after adjusting for sex, age, BMI, WHR, and HOMA-IR, while this correlation was lost after controlling for G3P.

Conclusion

Plasma asprosin is associated with kidney injury in diabetic conditions, and this association might be connected through inflammatory response. Further studies are needed to assess the role and mechanism of asprosin in DKD.

Effect of finerenone on nephrotic syndrome in patients with diabetic kidney disease

Introduction

Diabetic kidney disease (DKD) is an important complication of diabetes as it results in end-stage renal disease; hence, several drugs have been developed for its treatment. However, even with treatment with renin-angiotensin system inhibitors and sodium-glucose cotransporter-2 inhibitors, the residual risk of DKD remains. While this risk is an issue, the renoprotective effects of finerenone, a novel non-steroidal mineralocorticoid receptor antagonist, are becoming evident. High proteinuria increases the risk of cardiovascular death as well as renal failure. Hence, it is especially important to address cases of urine protein to nephrotic levels in DKD, however, no previous studies have assessed the safety and efficacy of finerenone in patients with DKD and nephrotic syndrome. Therefore, this study aimed to assess whether finerenone has a renoprotective effect in advanced DKD complicated by nephrotic syndrome.

Methods

Nine patients with DKD and nephrotic syndrome who received 10-20 mg/day of finerenone were retrospectively analyzed. The average observation period was 9.7 ± 3.4 months. Patients with serum potassium levels greater than 5.0 mEq/L at the start of finelenone were excluded. Changes in urinary protein levels, estimated glomerular filtration rate (eGFR), and serum potassium levels were studied before and after finerenone administration.

Results

The mean changes in the urinary protein creatinine ratio (UPCR) at baseline were 6.6 ± 2.0. After finerenone treatment, the mean UPCR decreased to -0.6 ± 3.9; however, this change was not statistically significant.The eGFR decline slope also tended to decrease with finerenone treatment (before vs. after: 3.1 ± 4.9 vs. -1.7 ± 3.2 mL/min/1.73 m2. Furthermore, finerenone did not increase serum potassium levels.

Conclusions

Patients treated with finerenone showed decreased UPCR; hence, it is suggested that finerenone may be effective in treating nephrotic syndrome in patients with DKD. These findings may be applicable to real-world clinical settings. Nonetheless, it is important to note that this study was a retrospective analysis of a single-center cohort and had a limited sample size, highlighting the need for additional large-scale investigations.

Effect of Sacubitril/Valsartan on Patients Having Heart Failure With Preserved Left Ventricular Ejection Fraction Undergoing Hemodialysis: A Long-term Observational Study

BACKGROUND/AIM

Sacubitril/valsartan (SV), a novel pharmacological class of angiotensin receptor neprilysin inhibitors, is effective in treating heart failure (HF) by inhibiting the degradation of natriuretic peptides and the renin-angiotensin-aldosterone system. However, no studies have observed the long-term effects of SV on patients with HF and preserved left ventricular ejection fraction (LVEF) undergoing hemodialysis (HD) over a long period.

PATIENTS AND METHODS

This single-center retrospective study of 21 months duration involved consecutive patients with HF and preserved LVEF undergoing HD, who received 50-200 mg/day. All patients were followed up regularly, and clinical, biochemical, and echocardiographic parameters were recorded at baseline and during follow-up. The efficacy and safety of SV were also analyzed.

RESULTS

This longitudinal study included nine patients, with a median age of 76 years. The median HD duration was 7 years. At baseline, the mean brain natriuretic peptide (BNP) was 133±73.6 pg/ml and that of LVEF was 66%±9%. After SV therapy, the systolic blood pressure, diastolic blood pressure, and heart rate decreased, albeit without statistical significance. BNP levels, LVEF, left atrial anteroposterior dimension, and left ventricular mass index did not change, compared to baseline values. No adverse effects were observed in any of the patients.

CONCLUSION

SV tended to decrease blood pressure and heart rate in patients with HF and preserved LVEF undergoing HD but did not alter cardiac function assessments, such as BNP or echocardiography.

Tirzepatide Reduces Fat Mass and Provides Good Glycaemic Control in Type 2 Diabetes Patients Undergoing Haemodialysis: A Single-Centre Retrospective Study

OBJECTIVE

Tirzepatide is an injectable peptide approved by the US Food and Drug Administration for the treatment of Type 2 diabetes (T2DM). Its weight-loss effect primarily targets fat reduction; however, such effect on patients with chronic kidney disease (CKD) undergoing haemodialysis (HD) has not been reported.

METHODS

Nine patients with CKD undergoing HD received weekly tirzepatide doses (2.5-7.5 mg) once a week. Evaluations encompassed tirzepatide's impact on dry weight (DW) and body composition assessed at baseline and study conclusion using bioelectrical impedance analysis. This longitudinal study included nine patients, with a median age of 53 years and median HD duration of 4 years.

RESULTS

Tirzepatide treatment significantly decreased glycated albumin compared with the value at baseline (22.7 ± 5.4 vs. 18.3 ± 2.5%, p = 0.028, respectively). Significant reductions were observed in DW (-1.0 kg, p = 0.024) and body mass index (-0.6 kg/m2, p = 0.050) following tirzepatide administration. Total fat mass was also reduced, but not significantly (- 2.51% from baseline, p = 0.214). In contrast, skeletal muscle mass was not decreased (-1.02% from baseline, p = 0.722). No serious side effects other than nausea were observed during the study period.

CONCLUSION

Tirzepatide effectively provides good glycaemic control in T2DM patients undergoing HD, decreasing DW by reducing body fat mass without increasing frailty risk.

Associations between cardiometabolic indices and the risk of diabetic kidney disease in patients with type 2 diabetes

BACKGROUND

This study was designed to assess the associations between emerging cardiometabolic indices-the atherogenic index of plasma (AIP), the stress hyperglycemia ratio (SHR), the triglyceride-glucose (TyG) index, and the homeostasis model assessment of insulin resistance (HOMA-IR)-and the incidence of diabetic kidney disease (DKD) in type 2 diabetes (T2D) patients.

METHODS

We consecutively enrolled 4351 T2D patients. The AIP, SHR, TyG index, and HOMA-IR were calculated from baseline parameters. DKD was defined as a urine albumin/creatinine ratio > 30 mg/g or an eGFR < 60 mL/min per 1.73 m. All participants were categorized into tertiles based on the cardiometabolic indices. Multivariate logistic regression models, restricted cubic splines, and receiver operating characteristic (ROC) curves were used for analysis.

RESULTS

A total of 1371 (31.5%) patients were diagnosed with DKD. A restricted cubic spline showed a J-shaped association of the AIP and TyG index with DKD, a log-shaped association between HOMA-IR and DKD, and a U-shaped association between the SHR and DKD incidence. Multivariate logistic regression revealed that individuals in the highest tertile of the four cardiometabolic indices had a significantly greater risk of DKD than did those in the lowest tertile (AIP: OR = 1.08, 95% CI = 1.02-1.14, P = 0.005; SHR: OR = 1.42, 95% CI = 1.12-1.81, P = 0.004; TyG index: OR = 1.86, 95% CI = 1.42-2.45, P < 0.001; HOMA-IR: OR = 2.24, 95% CI = 1.52-3.30, P < 0.001). The receiver operating characteristic curves showed that the HOMA-IR score was better than other indices at predicting the risk of DKD, with an optimal cutoff of 3.532.

CONCLUSIONS

Elevated AIP, SHR, TyG index and HOMA-IR are associated with a greater risk of DKD in patients with T2D. Among these indices, the HOMA-IR score demonstrated the strongest association with and predictive value for DKD incidence.

Bidirectional relation between dipeptidyl peptidase 4 and angiotensin II type I receptor signaling

Cardiometabolic diseases are often associated with heightened levels of angiotensin II (Ang II), which accounts for the observed oxidative stress, inflammation, and fibrosis. Accumulating evidence indicates a parallel upregulation of dipeptidyl dipeptidase 4 (DPP4) activity in cardiometabolic diseases, with its inhibition shown to mitigate oxidative stress, inflammation, and fibrosis. These findings highlight an overlap between the pathophysiological mechanisms used by Ang II and DPP4. Recent evidence demonstrates that targeted inhibition of DPP4 prevents the rise in Ang II and its associated molecules in experimental models of cardiometabolic diseases. Similarly, inhibitors of the angiotensin I-converting enzyme (ACE) or Ang II type 1 receptor (AT1R) blockers downregulate DPP4 activity, establishing a bidirectional relationship between DPP4 and Ang II. Here, we discuss the current evidence supporting the cross talk between Ang II and DPP4, along with the potential mechanisms promoting this cross regulation. A comprehensive analysis of this bidirectional relationship across tissues will advance our understanding of how DPP4 and Ang II collectively promote the development and progression of cardiometabolic diseases.

Protective Factors and the Pathogenesis of Complications in Diabetes

Chronic complications of diabetes are due to myriad disorders of numerous metabolic pathways that are responsible for most of the morbidity and mortality associated with the disease. Traditionally, diabetes complications are divided into those of microvascular and macrovascular origin. We suggest revising this antiquated classification into diabetes complications of vascular, parenchymal, and hybrid (both vascular and parenchymal) tissue origin, since the profile of diabetes complications ranges from those involving only vascular tissues to those involving mostly parenchymal organs. A major paradigm shift has occurred in recent years regarding the pathogenesis of diabetes complications, in which the focus has shifted from studies on risks to those on the interplay between risk and protective factors. While risk factors are clearly important for the development of chronic complications in diabetes, recent studies have established that protective factors are equally significant in modulating the development and severity of diabetes complications. These protective responses may help explain the differential severity of complications, and even the lack of pathologies, in some tissues. Nevertheless, despite the growing number of studies on this field, comprehensive reviews on protective factors and their mechanisms of action are not available. This review thus focused on the clinical, biochemical, and molecular mechanisms that support the idea of endogenous protective factors, and their roles in the initiation and progression of chronic complications in diabetes. In addition, this review also aimed to identify the main needs of this field for future studies.

PGC1-α in diabetic kidney disease: unraveling renoprotection and molecular mechanisms

Mitochondrial dysfunction represents a pivotal aspect of the pathogenesis and progression of diabetic kidney disease (DKD). Central to the orchestration of mitochondrial biogenesis is the peroxisome proliferator-activated receptor γ coactivator 1-α (PGC1-α), a master regulator with a profound impact on mitochondrial function. In the context of DKD, PGC1-α exhibits significant downregulation within intrinsic renal cells, precipitating a cascade of deleterious events. This includes a reduction in mitochondrial biogenesis, heightened levels of mitochondrial oxidative stress, perturbed mitochondrial dynamics, and dysregulated mitophagy. Concurrently, structural and functional abnormalities within the mitochondrial network ensue. In stark contrast, the sustained expression of PGC1-α emerges as a beacon of hope in maintaining mitochondrial homeostasis within intrinsic renal cells, ultimately demonstrating an impressive renoprotective potential in animal models afflicted with DKD. This comprehensive review aims to delve into the recent advancements in our understanding of the renoprotective properties wielded by PGC1-α. Specifically, it elucidates the potential molecular mechanisms underlying PGC1-α's protective effects within renal tubular epithelial cells, podocytes, glomerular endothelial cells, and mesangial cells in the context of DKD. By shedding light on these intricate mechanisms, we aspire to provide valuable insights that may pave the way for innovative therapeutic interventions in the management of DKD.

Effects of Oral Semaglutide on Renal Function in Diabetic Kidney Disease: A Short-term Clinical Study

BACKGROUND/AIM

In the SUSTAIN-6 trial, semaglutide reduced the risk of worsening nephropathy in patients with type 2 diabetes. The objective of this retrospective study was to elucidate the effect and safety of oral semaglutide (Rybelsus®) in patients with diabetic kidney disease (DKD).

PATIENTS AND METHODS

Six patients with DKD received 3 mg/day semaglutide orally. The observation period was 9.0±5.0 months. Changes in estimated glomerular filtration rate (eGFR), urinary protein, fasting blood glucose, and hemoglobin A1c were studied from 6 months before the administration of oral semaglutide until 6 months after administration.

RESULTS

The change in eGFR over the 6 months prior to semaglutide administration was -1.2±1.6 ml/min/1.73 m2, showing a trend for a decrease; although not statistically significant, the change at 6 months after oral semaglutide initiation showed improved eGFR (1-50.7±1.8 ml/min/1.73 m2). Proteinuria was not reduced after treatment with oral semaglutide. No significant adverse effects (including retinopathy) were observed in any patient during the study.

CONCLUSION

Despite the small sample size and short observation period, oral semaglutide was found to be a relatively well-tolerated drug for patients with DKD.

The Current Place of DPP4 Inhibitors in the Evolving Landscape of Type 2 Diabetes Management: Is It Time to Bid Adieu?

During the last decade, the landscape of type 2 diabetes (T2D) management has been completely transformed, moving from a glucose-centric perspective to a holistic approach that also takes into account weight control and organ protection. Dipeptidyl peptidase-4 inhibitors (DPP4i) are oral agents that have been used for the treatment of T2D for almost 20 years. Although they present an excellent safety profile, including the risk of hypoglycemia, they lack the spectacular cardiorenal benefits and weight-loss effects of the newer antidiabetic agents. This poses the question of whether they still deserve a place in the arsenal of drugs against T2D. In this article, we use a hypothetical case scenario to illustrate possible patient profiles where DPP4i could prove useful in the clinical setting. We discuss the advantages and disadvantages of the category, focusing on glycemic control, weight management, and cardiorenal protection, which are the pillars of modern T2D management, also considering its safety profile and cost-effectiveness. We conclude that in most cases, DPP4i present a more favorable risk-benefit ratio compared to sulfonylureas, which are still widely prescribed throughout the world. We also suggest that future research should clarify the reasons behind the contradictory findings between human and animal studies on cardiorenal effects of the class and identify subgroups of patients who would derive most benefit with DPP4i treatment.

Incretins and microvascular complications of diabetes: neuropathy, nephropathy, retinopathy and microangiopathy

Glucagon-like peptide-1 receptor agonists (GLP-1RAs, incretin mimetics) and dipeptidyl peptidase-4 inhibitors (DPP-4is, incretin enhancers) are glucose-lowering therapies with proven cardiovascular safety, but their effect on microvascular disease is not fully understood. Both therapies increase GLP-1 receptor agonism, which is associated with attenuation of numerous pathological processes that may lead to microvascular benefits, including decreased reactive oxygen species (ROS) production, decreased inflammation and improved vascular function. DPP-4is also increase stromal cell-derived factor-1 (SDF-1), which is associated with neovascularisation and tissue repair. Rodent studies demonstrate several benefits of these agents in the prevention or reversal of nephropathy, retinopathy and neuropathy, but evidence from human populations is less clear. For nephropathy risk in human clinical trials, meta-analyses demonstrate that GLP-1RAs reduce the risk of a composite renal outcome (doubling of serum creatinine, eGFR reduction of 30%, end-stage renal disease or renal death), whereas the benefits of DPP-4is appear to be limited to reductions in the risk of albuminuria. The relationship between GLP-1RAs and retinopathy is less clear. Many large trials and meta-analyses show no effect, but an observed increase in the risk of retinopathy complications with semaglutide therapy (a GLP-1RA) in the SUSTAIN-6 trial warrants caution, particularly in individuals with baseline retinopathy. Similarly, DPP-4is are associated with increased retinopathy risk in both trials and meta-analysis. The association between GLP-1RAs and peripheral neuropathy is unclear due to little trial evidence. For DPP-4is, one trial and several observational studies show a reduced risk of peripheral neuropathy, with others reporting no effect. Evidence in other less-established microvascular outcomes, such as microvascular angina, cerebral small vessel disease, skeletal muscle microvascular disease and autonomic neuropathies (e.g. cardiac autonomic neuropathy, gastroparesis, erectile dysfunction), is sparse. In conclusion, GLP-1RAs are protective against nephropathy, whereas DPP-4is are protective against albuminuria and potentially peripheral neuropathy. Caution is advised with DPP-4is and semaglutide, particularly for patients with background retinopathy, due to increased risk of retinopathy. Well-designed trials powered for microvascular outcomes are needed to clarify associations of incretin therapies and microvascular diseases.

Effects of liraglutide on extraglycemic inflammatory markers and renal hemodynamic parameters in diabetic kidney disease (DKD)

Diabetic kidney disease (DKD) was the leading cause of kidney disease, which has been a crucial public health. Liraglutide is a drug, widely used for DKD treatment globally. However, the extraglycemic inflammatory markers and renal hemodynamic parameters of DKD patients treated with liraglutide has been not reported. In this study, 160 patients with early DKD were enrolled, 80 cases in the control group and 80 cases in the treatment group, respectively. The individuals in the control group were treated with metformin, while the individuals in the treatment group were treated with liraglutide and metformin for 3 months. The urinary microalbumin and urinary creatinine was measured to calculate the ratio (UACR), while the Doppler ultrasound were measured before and after treatment. After 3 months of treatment, body mass index (BMI), waist circumference (WC) and low-density lipoprotein cholesterol (LDL) in the treatment group were significantly decreased compared with before and after treatment in the control group; the levels of cystatin and UACR in treatment group were lower than before treatment and control group; The end-diastolic blood flow velocity (EDV) of renal artery and segment artery in treatment group was significantly higher than that before treatment and control group; The levels of CRP, TNF-α and IL-6 in the treatment group after treatment were lower than those before treatment and those in the control group. After 3 months of treatment, blood cystatin in the treatment group decreased significantly compared with before treatment and after treatment in the control group, with statistical significance After 3 months of treatment, the EDV of renal artery and renal segment in treatment group was significantly higher than that before treatment and control group, the peak systolic blood flow velocity (PSV) and EDV of renal interlobar artery in treatment group were significantly higher than those before treatment and control group. The resistance index (RI) was significantly lower than that before treatment and control group. Liraglutide can reduce inflammatory indicators, renal artery blood flow and renal function indicators in early DKD patients.

Current findings on the efficacy of incretin-based drugs for diabetic kidney disease: A narrative review

Diabetic kidney disease (DKD) is the most common cause of chronic kidney disease (CKD), leading end-stage renal disease. Thus, DKD is one of the most important diabetic complications. Incretin-based therapeutic agents, such as glucagon-like peptide-1 (GLP-1) receptor agonizts and dipeptidyl peptidase-4 (DPP-4) inhibitors have been reported to elicit vasotropic actions, suggesting a potential for effecting reduction in DKD. Glucose-dependent insulinotropic polypeptide (GIP) is also classified as an incretin. However, the insulin action after GIP secretion is known to be drastically reduced in patients with type 2 diabetes. Therefore, GIP has been formally considered unsuitable as a treatment for type 2 diabetes in the past. This concept is changing as it has been reported that resistance to GIP can be reversed and its effect restored with improved glycemic control. The development of novel dual- or triple- receptor agonizts that can bind to the receptors, not only for GLP-1 but also to GIP and glucagon receptors, is intended to simultaneously address several metabolic pathways including protein, lipid, and carbohydrate metabolism. These led to the development of GIP receptor agonist-based drugs for type 2 diabetes. The possibility of combined GIP/GLP-1 receptor agonist was also explored. The novel dual GIP and GLP-1 receptor agonist tirzepatide has recently been launched (Mounjaro®, Lilly). We have revealed precise mechanisms of the renoprotective effect of GLP-1 receptor agonizts or DPP-4 inhibitors, while the long-term effect of tirzepatide will need to be determined and its potential effects on kidneys should be properly tested.

Effect of finerenone on diabetic kidney disease outcomes with estimated glomerular filtration rate below 25 mL/min/1.73 m2

Background

In the Finerenone in Reducing Cardiovascular Mortality and Morbidity in Diabetic Kidney Disease trial, finerenone reduced the risk of cardiovascular events in patients with chronic kidney disease (CKD) and type 2 diabetes, while in the Finerenone in Reducing Kidney Failure and Disease Progression in Diabetic Kidney Disease trial, it improved renal and cardiovascular outcomes in patients with advanced CKD. However, no previous studies have assessed patients with CKD and type 2 diabetes with an estimated glomerular filtration rate (eGFR) below 25 mL/min/1.73 m².

Methods

Nine patients with CKD and type 2 diabetes who received finerenone 10 mg/day were analyzed retrospectively. Changes in eGFR, urinary protein, and serum potassium levels were studied from 1 year before administration of finerenone until 6 months after administration.

Results

The mean baseline eGFR slope was -7.63 ± 9.84 (mL/min/1.73 m²/year). After finerenone treatment, the mean eGFR slope significantly improved -1.44 ± 3.17 (mL/min/1.73 m²/6 months, P=0.038). However, finerenone treatment did not significantly reduce proteinuria. Furthermore, finerenone did not increase serum potassium levels.

Conclusions

Patients treated with finerenone showed a significantly slower decline in eGFR. Furthermore, aside from the present study, no reports have indicated the effectiveness of finerenone in patients with advanced CKD with an eGFR below 25 mL/min/1.73 m². As confirmed in our clinical trials, the finding that finerenone is effective in a wide range of renal functions can be generalized to clinical practice. However, sample size in this study was small. Thus, further large-scale investigations will be needed.

Dietary Fat Modulation of Gut Microbiota and Impact on Regulatory Pathways Controlling Food Intake

Obesity is a multifactorial disease that continues to increase in prevalence worldwide. Emerging evidence has shown that the development of obesity may be influenced by taxonomic shifts in gut microbiota in response to the consumption of dietary fats. Further, these alterations in gut microbiota have been shown to promote important changes in satiation signals including gut hormones (leptin, ghrelin, GLP-1, peptide YY and CCK) and orexigenic and anorexigenic neuropeptides (AgRP, NPY, POMC, CART) that influence hyperphagia and therefore obesity. In this review, we highlight mechanisms by which gut microbiota can influence these satiation signals both locally in the gastrointestinal tract and via microbiota-gut-brain communication. Then, we describe the effects of dietary interventions and associated changes in gut microbiota on satiety signals through microbiota-dependent mechanisms. Lastly, we present microbiota optimizing therapies including prebiotics, probiotics, synbiotics and weight loss surgery that can help restore beneficial gut microbiota by enhancing satiety signals to reduce hyperphagia and subsequent obesity. Overall, a better understanding of the mechanisms by which dietary fats induce taxonomical shifts in gut microbiota and their impact on satiation signaling pathways will help develop more targeted therapeutic interventions in delaying the onset of obesity and in furthering its treatment.

Exendin-4 protects against high glucose-induced mitochondrial dysfunction and oxidative stress in SH-SY5Y neuroblastoma cells through GLP-1 receptor/Epac/Akt signaling

Mitochondrial dysfunction under diabetic condition leads to the development and progression of neurodegenerative complications. Recently, the beneficial effects of glucagon-like peptide-1 (GLP-1) receptor agonists on diabetic neuropathies have been widely recognized. However, molecular mechanisms underlying the neuroprotective effects of GLP-1 receptor agonists against high glucose (HG)-induced neuronal damages is not completely elucidated. Here, we investigated the underlying mechanisms of GLP-1 receptor agonist treatment against oxidative stress, mitochondrial dysfunction, and neuronal damages under HG-conditions mimicking a diabetic hyperglycemic state in SH-SY5Y neuroblastoma cells. We revealed that treatment with exendin-4, a GLP-1 receptor agonist, not only increased the expression of survival markers, phospho-Akt/Akt and Bcl-2, but also decreased the expression of pro-apoptotic marker, Bax, and reduced the levels of reactive oxygen species (ROS) defense markers (catalase, SOD-2, and HO-1) under HG conditions. The expressions of mitochondrial function associated genes, MCU and UCP3, and mitochondrial fission genes, DRP1 and FIS1, were decreased by exendin-4 compared to non-treated levels, while the protein expression levels of mitochondrial homeostasis regulators, Parkin and PINK1, were enhanced. In addition, blockade of Epac and Akt activities was able to antagonize these neuroprotective effects of exendin-4. Collectively, we demonstrated that stimulation of GLP-1 receptor propagates a neuroprotective cascade against the oxidative stresses and mitochondrial dysfunctions as well as augments survival through the Epac/Akt-dependent pathway. Therefore, the revealed mechanisms underlying GLP-1 receptor pathway by preserving mitochondrial homeostasis would be a therapeutic candidate to alleviate neuronal dysfunctions and delay the progression of diabetic neuropathies.

IgA nephropathy after COVID-19 vaccination and analysis of reported cases

Background

Immunoglobin A nephropathy (IgAN) is one of the most common forms of chronic glomerulonephritis and has been shown to occur in association with vaccinations. While various vaccines against COVID-19 have become widely used, their side effects, especially on IgAN following COVID-19 vaccines are still unclear. In this report, we describe the clinical courses and histopathologic findings of a newly diagnosed case of IgAN after receiving the mRNA-1273 (Moderna) COVID-19 vaccination.

Methods

This study presents a case of new-onset IgAN following mRNA-1273 COVID-19 (Moderna) vaccination. In addition, we review and analyze similar cases previously reported in the literature up to October 2022.

Results

Of the 52 cases reviewed, including our own, the majority of patients were female, and 64% of patients had initial onset IgAN. The most common manifestation was gross hematuria (87%), other associated symptoms were fever (44%), myalgia (8%), arthralgia (4%), and edema (4%). Many of these cases occurred after receiving Pfizer products as the second vaccination. Oral corticosteroids were used to 16 cases, and steroid pulse therapy was used to treat 7 cases.

Conclusion

While this is not a controlled study, it is important for physicians to consider the possibility that COVID-19 vaccines may provoke a flare of IgAN. Several therapeutic agents may be useful for treating COVID-19 vaccine-induced IgAN, although a specific mechanism or pathophysiological association cannot be confirmed without further research.

Predictive significance of glomerular insulin receptor substrate-1 in patients with diabetic kidney disease

Background

In rodents, glomerular expression of insulin receptor substrate 1 (IRS1) is decreased in diabetic kidney disease (DKD) and reduced associated functioning is involved in the development and progression of DKD. This study aimed to evaluate the significance of glomerular IRS1 expression in DKD patients, and investigated whether glomerular IRS1 expression can reflect renal pathology and predict renal outcomes.

Methods

This study included 10 patients who underwent renal biopsy and were diagnosed with DKD or minor glomerular abnormality (MGA). IRS1-positive cells were determined based on renal biopsy and immunostaining, and the associations of the number of these cells with baseline and prognostic parameters were analyzed.

Results

IRS1-positive cells were significantly decreased in DKD than in MGA. IRS1 positivity tended to be negatively correlated with global glomerulosclerosis and tubulointerstitial fibrosis. The rate of change in estimated glomerular filtration rate before and 12 months after renal biopsy was positively correlated to the number of IRS1-positive cells. Furthermore, a tendency towards negative correlation was observed between the number of glomerular IRS1-positive cells and the proteinuria.

Conclusions

This study shows the glomerular IRS1-positive cell count was significantly decreased in DKD, and that the degree IRS1 positivity was partially correlated with renal pathology and function.

Role of insulin signaling and its associated signaling in glomerulus for diabetic kidney disease

The number of patients with diabetic kidney disease (DKD) has been rising significantly over the last several decades and is one of the most frequent causes of chronic kidney disease (CKD) in the United States. Hyperglycemia accelerates development of DKD, a direct result of increased intracellular glucose availability. Two large clinical studies, the Diabetes Control and Complications Trial in type 1 diabetes and the United Kingdom Prospective Diabetes Study in type 2 diabetes showed that intensive glycemic control delayed the onset and the progression of DKD. On the other hand, it is reported that glycemic control alone is not sufficient to control DKD progression. Recent data support that insulin signaling and its associated signaling contribute significantly to preserve glomerular function. However, little is known about the key regulators of insulin signaling in glomerular component cells. In this review, we summarize the novel knowledge regarding the reno-protective effects of insulin signaling or its associated signaling in glomerular constituent cells on DKD.

Enarodustat Treatment for Renal Anemia in Patients With Non-dialysis Chronic Kidney Disease

BACKGROUND/AIM

Renal anemia is a major complication in patients with chronic kidney disease (CKD), leading to morbidity and mortality. Hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors (PHI), also called HIF stabilizers, increase endogenous erythropoietin production and are expected to be novel orally administrated agents for renal anemia in CKD. Enarodustat is being developed as an oral HIF-PHI. It was recently approved in Japan and clinical development is ongoing in the USA and South Korea. Therefore, there are only a few real-world data regarding treatment of renal anemia using enarodustat. This study evaluated the efficacy of enarodustat in patients with non-dialysis CKD.

PATIENTS AND METHODS

Nine patients (78±11 years old, male=6, female=3) were enrolled in this study. Patients received enarodustat as first-line therapy or changed from erythropoiesis stimulating agents (2-6 mg). The observation period was 4.8±2.0 months.

RESULTS

Levels of hemoglobin were effectively increased and maintained with enarodustat administration. C-reactive protein and serum ferritin were significantly decreased, but no change in renal function was observed. Furthermore, no serious adverse effects were recognized in all patients during the study.

CONCLUSION

Enarodustat is an effective and relatively well-tolerated agent for the treatment of renal anemia in patients with non-dialysis CKD.

The protective effects of SGLT-2 inhibitors, GLP-1 receptor agonists, and RAAS blockers against renal injury in patients with type 2 diabetes

Diabetic kidney disease is one of the most severe complications of type 2 diabetes mellitus. Patients with diabetic kidney disease have a worse prognosis in terms of mortality and morbidity, compared with patients who have diabetes alone. Strict control of blood pressure and blood glucose is the primary method for prevention of initial kidney damage and delaying further progression of existing damage. Other management approaches include the use of exogenous drugs that can effectively protect the kidneys from diabetes, such as sodium-glucose transporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and renin-angiotensin-aldosterone system blockers. These drugs may protect against kidney injury through various molecular mechanisms. This review focuses on renal impairment in patients with type 2 diabetes; it discusses the direct and indirect effects of sodium-glucose transporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and renin-angiotensin-aldosterone system blockers on diabetic kidney disease. Finally, it discusses the effects of combination treatment with two or three types of drugs in patients with chronic kidney disease.

Effects of incretin-based therapeutic agents including tirzepatide on renal outcomes in patients with type 2 diabetes: A systemic review and meta-analysis

Background

This meta-analysis was conducted to investigate the effects of incretin-based therapeutic agents, including the latest agent tirzepatide, on renal outcomes in patients with type 2 diabetes.

Methods

MEDLINE (via PubMed) and Cochrane databases were searched for studies involving incretin-based therapeutic agents up to July 2022. Randomized and controlled trials comparing incretin-based therapeutic agents with placebo or other antidiabetic agents, and reporting renal outcomes were selected. The inclusion criteria were items related to the effects on albuminuria and the kidney-specific composite outcomes. A network meta-analysis was conducted to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

Twelve trials consisting of 75,346 participants were included in this meta-analysis. Glucagon-like peptide-1 (GLP-1) receptor agonists reduced the risk of the kidney-specific composite outcome by 21% (HR 0.79, 95% CI 0.75-0.85), and worsening albuminuria by 24% (HR 0.76, 95% CI 0.71-0.82). In particular, the dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 receptor agonist tirzepatide remarkably reduced the risk of the kidney-specific composite outcome by 45% (HR 0.55, 95% CI 0.40-0.77), and worsening albuminuria by 62% (HR 0.38, 95% CI 0.24-0.61).

Conclusions

Among incretin-based therapeutic agents, tirzepatide was associated with a significantly reduced risk of diabetic kidney disease.

Multicentric IL-5-positive Castleman Disease With Nephrotic Syndrome Relapsed After Rituximab Treatment

BACKGROUND/AIM

To date, no reports of interleukin (IL)-5-producing Castleman disease with nephrotic syndrome and moreover no reports of relapse after remission with rituximab treatment, have been published.

CASE REPORT

A 67-year-old male presented to the Osaka Medical and Pharmaceutical University Hospital with a history of low-grade fever, papules, and nephrotic syndrome. Lymph nodes were palpated in the inguinal region. The patient showed anemia, eosinophilia, polyclonal hypergammaglobulinemia, and elevated interleukin (IL)-6 levels. Patient's serum IL-5 and IL-6 levels were measured using ELISA and immunohistochemical staining of lymph nodes was performed with antibodies specific to CD134. Histological examination confirmed diagnosis of a plasma cell variant of Castleman disease. After a total of four weekly doses of rituximab, urinary protein disappeared, and skin symptoms improved. However, one month after rituximab treatment, the skin rash worsened again, and eosinophils and IL-5 were elevated significantly.

CONCLUSION

This is the first report of recurrent Castleman disease with direct evidence of increased serum IL-5. It may be reasonable to use rituximab, an anti-CD20 antibody for treating the disease, however, for IL-5-producing cases the effect of rituximab may be partial.

Repurposing of Drugs for Cardiometabolic Disorders: An Out and Out Cumulation

Cardiometabolic disorders (CMD) is a constellation of metabolic predisposing factors for atherosclerosis such as insulin resistance (IR) or diabetes mellitus (DM), systemic hypertension, central obesity, and dyslipidemia. Cardiometabolic diseases (CMDs) continue to be the leading cause of mortality in both developed and developing nations, accounting for over 32% of all fatalities globally each year. Furthermore, dyslipidemia, angina, arrhythmia, heart failure, myocardial infarction (MI), and diabetes mellitus are the major causes of death, accounting for an estimated 19 million deaths in 2012. CVDs will kill more than 23 million individuals each year by 2030. Nonetheless, new drug development (NDD) in CMDs has been increasingly difficult in recent decades due to increased costs and a lower success rate. Drug repositioning in CMDs looks promising in this scenario for launching current medicines for new therapeutic indications. Repositioning is an ancient method that dates back to the 1960s and is mostly based on coincidental findings during medication trials. One significant advantage of repositioning is that the drug's safety profile is well known, lowering the odds of failure owing to undesirable toxic effects. Furthermore, repositioning takes less time and money than NDD. Given these facts, pharmaceutical corporations are becoming more interested in medication repositioning. In this follow-up, we discussed the notion of repositioning and provided some examples of repositioned medications in cardiometabolic disorders.

Toll-like receptors 2 and 4 stress signaling and sodium-glucose cotransporter-2 in kidney disease

Kidney disease is the 6th fastest-growing cause of death and a serious global health concern that urges effective therapeutic options. The inflammatory response is an initial reaction from immune and parenchymal cells in kidney diseases. Toll-like receptors (TLR) 2 and 4 are highly expressed by various kidney cells and respond to 'signaling danger' proteins, such as high mobility group box binding protein 1 (HMGB1) and prompt the progression of kidney disease by releasing inflammatory mediators. Burgeoning reports suggest that both SGLT2 and ER stress elevates TLR2/4 signaling via different axis. Moreover, SGLT2 signaling aggravates inflammation under the disease condition by promoting the NLR family pyrin domain-containing three inflammasomes and ER stress. Intriguingly, TLR2/4 downstream adaptors activate ER stress regulators. The above-discussed interactions imply that TLR2/4 does more than immune response during kidney disease. Here, we discuss in detail evidence of the roles and regulation of TLR2/4 in the context of a relationship between ER stress and SGLT2. Also, we highlighted different preclinical studies of SGLT2 inhibitors against TLR2/4 signaling in various kidney diseases. Moreover, we discuss the observational and interventional evidence about the relation between TLR2/4, ER stress, and SGLT2, which may represent the TLR2/4 as a potential therapeutic target for kidney disease.

Renal insulin resistance in type 2 diabetes mellitus and progression of chronic kidney disease: potential pathogenic mechanisms

INTRODUCTION

A bidirectional association exists between insulin resistance (IR) and chronic kidney disease (CKD) in Type 2 Diabetes Mellitus (T2DM). Baseline measures of IR are predictive of CKD progression, and uremia in progressive CKD is itself, in turn, associated with a worsening of IR. Pre-clinical research reveals that intrinsic IR in glomerular podocytes and the renal tubule may serve as a pathogenic driver of CKD in T2DM.

AREAS COVERED

The present manuscript takes as its point of departure, the recently identified prognostic utility of severe insulin resistance as a predictor of CKD in T2DM. Findings from a series of studies describing the association of IR with pathological alterations in both established, and less commonly assessed dynamic measures of renal impairment are discussed. Drawing upon the pre-clinical mechanistic evidence base, the cellular and molecular basis of intrinsic renal IR as a promoter of CKD is considered.

EXPERT OPINION

Measurement of insulin sensitivity may add value to profiling of renal risk in T2DM. Rational selection of therapeutic strategies targeting the enhancement of insulin sensitivity merits special attention regarding the personalized management of CKD in insulin resistance predominant T2DM.

Treatment of Renal Anemia in Patients With Hemodialysis Using Hypoxia-inducible Factor (HIF) Stabilizer, Roxadustat: A Short-term Clinical Study

BACKGROUND/AIM

Renal anemia is a major complication in patients with chronic kidney disease (CKD) and hemodialysis, increasing morbidity and mortality. Roxadustat is a novel oral hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor (PHI), which is administrated for renal anemia. Different from erythropoiesis-stimulating agents (ESAs), Roxadustat could increase erythropoietin physiologically, improving the therapeutic effects. It has not been so long since Roxadustat was approved by the European Commission (EC). Thus, only a few studies have reported on the treatment of renal anemia using Roxadustat.

PATIENTS AND METHODS

In this study, we evaluated the efficacy of Roxadustat in patients undergoing hemodialysis (HD). Nine patients under HD (72±10 years old) were enrolled in this study. Patients received Roxadustat first time or changed from ESAs (5-10 mg, 3 times a week after HD). Observation period was 5.3±2.9 months.

RESULTS

Roxadustat treatment effectively increased and maintained hemoglobin levels. Levels of ferritin and C-reactive protein tended to decrease, but the difference was not statistically significant. No significant adverse effects were observed in all patients during the study.

CONCLUSION

Roxadustat is effective and relatively tolerant for treating renal anemia in patients subjected to hemodialysis.

A Narrative Review of Diabetic Kidney Disease: Previous and Current Evidence-Based Therapeutic Approaches

Diabetic kidney disease (DKD) is one of the most important diabetic complications. DKD is also the most common cause of chronic kidney disease (CKD) and end-stage renal disease. This review focused on potential therapeutic drugs for which there is established evidence of treatment for DKD. The earliest evidence for DKD treatment was established with renin-angiotensin system (RAS) inhibitors; however, their efficacy was partial. Recently, the sodium-glucose co-transporter 2 (SGLT2) inhibitors, including empagliflozin (EMPA-REG Outcome), canagliflozin (CREDENCE trial), and dapagliflozin (DAPA-CKD), demonstrated a significant and clinically relevant reduction in the risks of albuminuria and progression of nephropathy, doubling of serum creatinine levels, and initiation of renal replacement therapy. Additionally, incretin-based therapeutic agents, such as glucagon-like peptide 1, liraglutide (LEADER), and dipeptidyl peptidase 4 inhibitors, linagliptin (CARMERINA) have elicited vasotropic actions, suggesting a potential for reducing the risk of DKD. Until recently, mineralocorticoid receptor antagonists (MRAs) have not been suitable for DKD treatment because of their adverse effect of hyperkalemia. In contrast, finerenone, a non-steroidal MRA, significantly reduced renal composite endpoint without severe hyperkalemia that would force its discontinuation (FIDELIO-DKD). Thus, the mainstay treatments of DKD are RAS inhibitors, SGLT2 inhibitors, incretin-based therapeutic agents, and non-steroidal MRA, or in other words, the DKD "fantastic four".

Clinical Analysis of the Renal Protective Effect of GLP-1 on Diabetic Patients Based on Edge Detection

With the rapid development of IoT technology, it is a new trend to combine edge computing with smart medicine in order to better develop modern medicine, avoid the crisis of information “sibling,” and meet the requirements of timeliness and computational performance of the massive data generated by edge devices. However, edge computing is somewhat open and prone to security risks, so the security and privacy protection of edge computing systems for smart healthcare is receiving increasing attention. The two groups were compared before and after treatment for blood glucose, blood lipids, blood pressure, renal function, serum advanced glycosylation end products (AGEs) and cyclic adenosine monophosphate (cAMP), serum oxidative stress indicators, and levels of cAMP/PKA signalling pathway-related proteins in peripheral blood mononuclear cells. The results of this study show that the reduction of AGEs, the improvement of oxidative stress, and the regulation of the cAMP/PKA signalling pathway may be associated with a protective effect against early DKD. By introducing the edge computing system and its architecture for smart healthcare, we describe the security risks encountered by smart healthcare in edge computing, introduce the solutions proposed by some scholars to address the security risks, and finally summarize the security protection framework and discuss the specific solutions for security and privacy protection under this framework, which will provide some help for the credible research of smart healthcare edge computing.

Renoprotective Effect of Liraglutide Is Mediated via the Inhibition of TGF-Beta 1 in an LLC-PK1 Cell Model of Diabetic Nephropathy

Background: Recently published research demonstrated direct renoprotective effects of the glucagon-like peptide-1 receptor agonist GLP 1 RA, but the relevant molecular mechanisms are still not clear. The aim of this research was to assess the effects of Liraglutide in a cell culture model of diabetic nephropathy on cell viability, antioxidant (GSH) and transforming growth factor beta 1 (TGF- β1) levels and extracellular matrix (ECM) expression. The metabolic activity in hyperglycemic conditions and the effect of Liraglutide treatment were assessed by measuring Akt, pAkt, GSK3β, pGSK3β, pSTAT3, SOCS3, iNOS and NOX4 protein expression with Western blot. F actin distribution was used to assess the structural changes of the cells upon treatment. Materials and methods: The cells were exposed to high glucose (HG30 mM) followed by 0.5 mM H2O2 and a combination of glucose and H2O2 during 24 h. Subsequently, the cells were treated with different combinations of HG30, H2O2 and Liraglutide. Cell viability was determined by an MTT colorimetric test, and the GSH, TGF-β1 concentration and ECM expression were measured using a spectrophotometric/microplate reader assay and an ELISA kit, respectively. Western blotting was used to detect the protein level of Akt, pAkt, GSK3β, pGSK3β, pSTAT3, SOCS3, iNOS and NOX4. The F-actin cytoskeleton was visualized with Phalloidin stain and subsequently quantified. Results: Cell viability was decreased as well as GSH levels in cells treated with a combination of HG30/H2O2, and HG30 alone (p < 0.001). The addition of Liraglutide improved the viability in cells treated with HG30, but it did not affect the cell viability in the cell treated with the addition of H2O2. GSH increased with the addition of Liraglutide in HG30/H2O2 (p < 0.001) treated cells, with no effect in cells treated only with HG30. TGF-β1 levels (p < 0.001) were significantly increased in HG30 and HG30/H2O2. The addition of Liraglutide significantly decreased the TGF-β1 levels (p < 0.01; p < 0.05) in all treated cells. The synthesis of collagen was significantly increased in HG30/H2O2 (p < 0.001), while the addition of Liraglutide in HG30/H2O2 significantly decreased collagen (p < 0.001). Akt signaling was not significantly affected by treatment. The GSK3b and NOX4 levels were significantly reduced (p < 0.01) after the peroxide and glucose treatment, with the observable restoration upon the addition of Liraglutide suggesting an important role of Liraglutide in oxidative status regulation and mitochondrial activity. The treatment with Liraglutide significantly upregulated STAT3 (p < 0.01) activity, with no change in SOCS3 indicating a selective regulation of the STAT 3 signaling pathway in glucose and the oxidative overloaded environment. A significant reduction in the distribution of F-actin was observed in cells treated with HG30/H2O2 (p < 0.01). The addition of Liraglutide to HG30-treated cells led to a significant decrease of distribution of F-actin (p < 0.001). Conclusion: The protective effect of Liraglutide is mediated through the inhibition of TGF beta, but this effect is dependent on the extent of cellular damage and the type of toxic environment. Based on the WB analysis we have revealed the signaling pathways involved in cytoprotective and cytotoxic effects of the drug itself, and further molecular studies in vitro and vivo are required to elucidate the complexity of the pathophysiological mechanisms of Liraglutide under conditions of hyperglycemia and oxidative stress.