The potential and pitfalls of GLP-1 receptor agonists for renal protection in type 2 diabetes

Glucagon-Like Peptide 1 Receptor Agonists and Sodium-Glucose Cotransporter 2 Inhibitors Improve Renal Resistive Index in Patients With Type 2 Diabetes: A 26-Week Prospective Observational Real-Life Study

Diabetic kidney disease (DKD) is one of the most life-threatening complications of diabetes and a leading cause of chronic kidney disease. Glucagon-like peptide 1 receptor agonists (GLP1-RAs) or sodium-glucose cotransporter 2 inhibitors (SGLT2is) appear to improve renal outcome in patients with Type 2 diabetes (T2D). In this context, the renal resistive index (RRI) is a useful doppler measure to study DKD and predict its evolution. The aim of this work was to study the effect of treatment with GLP1-RA or SGLT2i on RRI and the relationship between RRI and glycometabolic parameters. One hundred forty-five patients with T2D were enrolled in the study and treated for 26 weeks with once-weekly GLP1-RA (38 patients with dulaglutide and 39 with semaglutide), SGLT2i (40 patients), or other therapies (28 control patients). Clinical, anthropometric, and hematochemical parameters and RRI were measured at baseline (T0) and after 6 months of treatment (T6). Changes at 6 months were studied and compared by treatment group. Patients were predominantly male (58.6%), overweight (93.0%) or frankly obese (60.0%), with hypertension (90.0%) and high (> 0.64) or pathological (> 0.7) RRI values (82.0% or 37.0%, respectively). At baseline, RRI correlated positively with age, fasting blood glucose, glycated hemoglobin (HbA1c), triglycerides, and albuminuria and negatively with estimated-glomerular filtration rate (e-GFR). At T6, patients treated with either GLP1-RA or SGLT2i showed a significant improvement in RRI but not in albuminuria or e-GFR, compared with homologous at baseline. In particular, RRI normalized in 32% and 30% of patients on therapy with GLP1-RA and SGLT2i, respectively, while remaining almost unchanged in controls. Notably, the RRI improvement was independent of age, gender, diabetes duration, and changes in BMI, waist circumference, HbA1c, and e-GFR. In conclusion, RRI can be used to detect early kidney damage and follow the evolution of DKD. GLP1-RA and SGLT2i improve RRI, demonstrating benefits on cardiovascular risk and renal outcomes.

Syringaldehyde Alleviates Cardiac Hypertrophy Induced by Hyperglycemia in H9c2 Cells Through GLP-1 Receptor Signals

Background: Cardiac hypertrophy is a significant complication of diabetes, often triggered by hyperglycemia. Glucagon-like peptide-1 (GLP-1) receptor agonists alleviate cardiac hypertrophy, but their efficacy diminishes under GLP-1 resistance. Syringaldehyde (SA), a natural phenolic compound, may activate GLP-1 receptors and mitigate hypertrophy. This study explores SA's therapeutic potential in hyperglycemia-induced cardiac hypertrophy in H9c2 cardiomyocytes. Methods: H9c2 cells were exposed to high glucose to induce hypertrophy. Cells were treated with varying SA concentrations, and hypertrophic biomarkers were analyzed using ELISA, qPCR, and Western blot. Results: SA reduced cell size and hypertrophic biomarkers in a dose-dependent manner while increasing GLP-1 receptor expression and cAMP levels. These effects were attenuated in GLP-1-resistant cells, highlighting the role of GLP-1 receptor activation. AMPK activation was essential, as its inhibition abolished SA's effects. SA also decreased O-linked N-acetylglucosamine transferase (OGT) expression via AMPK activation, contributing to reduced hypertrophy. Conclusions: SA alleviates hyperglycemia-induced cardiac hypertrophy in H9c2 cells by activating the GLP-1 receptor and AMPK signaling pathway.

GLP-1 Receptor Agonists and Diabetic Kidney Disease: A Game Charger in the Field?

Kidney disease is a public health epidemic affecting 10% of the population worldwide with a constantly rising incidence, and it is an important contributor to morbidity and mortality. Type 2 diabetes mellitus (T2DM) is a chronic complex condition with a rising incidence worldwide. T2DM remains the principal cause of chronic kidney disease (CKD), which is related to a high risk for cardiovascular (CV) events, end-stage kidney disease (ESKD), and, overall, considerable morbidity and mortality. In the past few decades, various therapeutic treatments have targeted the culprit pathways for slowing CKD progression, with partial success. Thus, despite new advances in patients' treatment, progressive loss of kidney function or death from T2DM and CKD complications compel new therapeutic pathways. Renin-angiotensin-aldosterone-system-blocking agents have been the only treatment until recently. On top of this, sodium-glucose co-transporter 2 inhibitors along with finerenone showed an impressive ability to reduce the progression of kidney disease and cardiovascular events in diabetic patients with CKD. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) can play a special role and could be a game changer in this field. The latest FLOW trial confirmed multiple favorable clinical effects on renal, cardiovascular, and survival outcomes among high-risk patients treated with semaglutide and supports a significant therapeutic role for GLP-1RAs in this population, although larger-scale evaluation of their risks is needed, given their increasing use.

Liraglutide and resveratrol alleviated cyclosporin A induced nephrotoxicity in rats through improving antioxidant status, apoptosis and pro-inflammatory markers

The recent study delves into the role of both liraglutide and/or resveratrol on the nephropathic affection in rats treated with cyclosporine A (CsA). Rats were intoxicated with CsA (25 mg/kg) orally for 21 days and were supplemented with liraglutide (30 μg/kg) s/c daily and 20 mg/kg of resveratrol (20 mg/kg) orally. At the end of the experiment, serum samples and renal tissues were collected to determine renal damage markers, apoptotic markers, proinflammatory markers, and antioxidant status markers. Kidney function tests and antioxidant activity notably improved in the treated rats (CsA + Lir/CsA + Res/CsA + Lir + Res). Moreover, both Lir and/or Res enhanced Bcl-2 levels while down-regulating the Bax levels in rats treated with CsA. Interestingly, the immune-staining for tumor necrosis factor (TNF-α) was tested negative and mild positive in renal tissue of rats given Lir and/or Res while being treated with Cs A which indicated their anti-inflammatory effect that reduced the renal damage. The findings of this investigation revealed the ameliorative anti-inflammatory in addition to the antioxidant role of both liraglutide and resveratrol against the kidney damage caused due to CsA administration.

Sodium-glucose cotransporter 2 inhibitors and renin-angiotensin-aldosterone system, possible cellular interactions and benefits

Sodium glucose cotransporter 2 inhibitors (SGLT2is) are a newly developed class of anti-diabetics which exert potent hypoglycemic effects in the diabetic milieu. However, the evidence suggests that they also have extra-glycemic effects. The renin-angiotensin-aldosterone system (RAAS) is a hormonal system widely distributed in the body that is important for water and electrolyte homeostasis as well as renal and cardiovascular function. Therefore, modulating RAAS activity is a main goal in patients, notably diabetic patients, which are at higher risk of complications involving these organ systems. Some studies have suggested that SGLT2is have modulatory effects on RAAS activity in addition to their hypoglycemic effects and, thus, these drugs can be considered as promising therapeutic agents for renal and cardiovascular disorders. However, the exact molecular interactions between SGLT2 inhibition and RAAS activity are not clearly understood. Therefore, in the current study we surveyed the literature for possible molecular mechanisms by which SGLT2is modulate RAAS activity.

Real-world clinical evidence of oral semaglutide on metabolic abnormalities in subjects with type 2 diabetes: a multicenter retrospective observational study (the Sapporo-Oral SEMA study)

Oral semaglutide has potent anti-hyperglycemic efficacy in phase III trials. However, the complicated dosing instructions hamper to use this drug; therefore, we evaluated the efficacy and safety of oral semaglutide in subjects with type 2 diabetes in a real-world clinical setting. In this multi-center retrospective observational study, we analyzed subjects with type 2 diabetes newly treated with an oral semaglutide for >6 months at four medical centers located in Sapporo, Japan. The changes in glycated hemoglobin, body weight, and other metabolic parameters were evaluated and any adverse event leading to semaglutide discontinuation were recorded from February 2021 to December 2022. This study was registered with the University Hospital Medical Information Network Center (UMIN000050583). Of 543 subjects who met the inclusion criteria, data for 434 subjects (age 55.5 ± 12.6 years; body mass index 29.6 ± 6.0 kg/m2) were analyzed. After a 6 months of observation period, semaglutide 3 mg, 7 mg, or 14 mg was used by 55 (12.7%), 241 (55.5%), and 138 (31.8%) of subjects, respectively. Both glycated hemoglobin and body weight significantly improved: 7.65 ± 1.11% to 6.88 ± 0.91% (p < 0.001) and 80.2 ± 19.2 kg to 77.6 ± 19.2 kg (p < 0.001), respectively. Efficacy was also confirmed in the subgroup switched from other anti-hyperglycemic agents, including dipeptidyl peptidase-4 inhibitors. In total, 154 subjects had symptomatic gastrointestinal symptoms and 39 (7.2%) were discontinued semaglutide due to the adverse events. None of the participants experienced severe hypoglycemic events. Oral semaglutide in subjects with type 2 diabetes improved glycemic control and body weight in a real-world clinical setting.

Design and discovery of a highly potent ultralong-acting GLP-1 and glucagon co-agonist for attenuating renal fibrosis

The role of co-agonists of glucagon-like peptide-1 receptor (GLP-1R) and glucagon receptor (GCGR) in chronic kidney disease (CKD) remains unclear. Herein we found that GLP-1R and GCGR expression levels were lower in the kidneys of mice with CKD compared to healthy mice and were correlated with disease severity. Interestingly, GLP-1R or GCGR knockdown aggravated the progression of kidney injury in both diabetic db/db mice and non-diabetic mice undergoing unilateral ureteral obstruction (UUO). Based on the importance of GLP-1R and GCGR in CKD, we reported a novel monomeric peptide, 1907-B, with dual-agonism on both GLP-1R and GCGR. The data confirmed that 1907-B had a longer half-life than long-acting semaglutide in rats or cynomolgus monkeys (∼2-3 fold) and exhibited better therapeutic contribution to CKD than best-in-class monoagonists, semaglutide, or glucagon, in db/db mice and UUO mice. Various lock-of-function models, including selective pharmacological activation and genetic knockdown, confirmed that 1907-B's effects on ameliorating diabetic nephropathy in db/db mice, as well as inhibiting kidney fibrosis in UUO mice, were mediated through GLP-1 and glucagon signaling. These findings highlight that 1907-B, a novel GLP-1R and GCGR co-agonist, exerts multifactorial improvement in kidney injuries and is an effective and promising therapeutic option for CKD treatment.

Albuminuria-lowering effect of adding semaglutide on top of empagliflozin in individuals with type 2 diabetes: A randomized and placebo-controlled study

AIM

To investigate whether combined treatment with empagliflozin (a sodium-glucose cotransporter-2 inhibitor) and semaglutide (a glucagon-like peptide-1 receptor agonist) can reduce urinary albumin-creatinine ratio (UACR) compared to treatment with empagliflozin alone in individuals with type 2 diabetes (T2D) and albuminuria.

METHODS

We conducted a randomized, placebo-controlled, double-blind, parallel study including 60 individuals with T2D and albuminuria. All participants initiated open-label empagliflozin 25 mg once daily, on top of renin-angiotensin system inhibition, in a run-in period of 26 weeks. Subsequently, participants were randomized to semaglutide or placebo 1 mg once weekly for 26 weeks. The primary endpoint was change in UACR. Secondary endpoints were change in: (i) measured glomerular filtration rate (GFR); (ii) 24-hour systolic blood pressure; (iii) glycated haemoglobin (HbA1c) level; (iv) body weight; and (v) plasma renin and aldosterone levels.

RESULTS

Addition of semaglutide to empagliflozin provided no additional change in UACR from randomization to end-of-treatment. The mean (95% confidence interval) difference in UACR was -22 (-44; 10)% (P = 0.15) between treatment groups. Neither GFR, 24-hour blood pressure, body weight, nor plasma renin activity was changed with semaglutide. HbA1c (-8 [-13; -3] mmol/mol; P = 0.003) and plasma aldosterone (-30 [-50; -3] pmol/L; P = 0.035) were reduced with semaglutide compared to placebo.

CONCLUSIONS

Semaglutide added to empagliflozin did not change UACR, measured GFR, 24-hour systolic blood pressure, body weight or plasma renin levels in individuals with T2D and albuminuria. Semaglutide improved glycaemic control and plasma aldosterone levels compared to placebo.

Glucagon-like peptide-1 receptor signaling modifies the extent of diabetic kidney disease through dampening the receptor for advanced glycation end products-induced inflammation

Glucagon like peptide-1 (GLP-1) is a hormone produced and released by cells of the gastrointestinal tract following meal ingestion. GLP-1 receptor agonists (GLP-1RA) exhibit kidney-protective actions through poorly understood mechanisms. Here we interrogated whether the receptor for advanced glycation end products (RAGE) plays a role in mediating the actions of GLP-1 on inflammation and diabetic kidney disease. Mice with deletion of the GLP-1 receptor displayed an abnormal kidney phenotype that was accelerated by diabetes and improved with co-deletion of RAGE in vivo. Activation of the GLP-1 receptor pathway with liraglutide, an anti-diabetic treatment, downregulated kidney RAGE, reduced the expansion of bone marrow myeloid progenitors, promoted M2-like macrophage polarization and lessened markers of kidney damage in diabetic mice. Single cell transcriptomics revealed that liraglutide induced distinct transcriptional changes in kidney endothelial, proximal tubular, podocyte and macrophage cells, which were dominated by pathways involved in nutrient transport and utilization, redox sensing and the resolution of inflammation. The kidney-protective action of liraglutide was corroborated in a non-diabetic model of chronic kidney disease, the subtotal nephrectomised rat. Thus, our findings identify a novel glucose-independent kidney-protective action of GLP-1-based therapies in diabetic kidney disease and provide a valuable resource for exploring the cell-specific kidney transcriptional response ensuing from pharmacological GLP-1R agonism.

In vivo mapping of hemodynamic responses mediated by tubuloglomerular feedback in hypertensive kidneys

The kidney has a sophisticated vascular structure that performs the unique function of filtering blood and managing blood pressure. Tubuloglomerular feedback is an intra-nephron negative feedback mechanism stabilizing single-nephron blood flow, glomerular filtration rate, and tubular flow rate, which is exhibited as self-sustained oscillations in single-nephron blood flow. We report the application of multi-scale laser speckle imaging to monitor global blood flow changes across the kidney surface (low zoom) and local changes in individual microvessels (high zoom) in normotensive and spontaneously hypertensive rats in vivo. We reveal significant differences in the parameters of TGF-mediated hemodynamics and patterns of synchronization. Furthermore, systemic infusion of a glucagon-like-peptide-1 receptor agonist, a potential renoprotective agent, induces vasodilation in both groups but only alters the magnitude of the TGF in Sprague Dawleys, although the underlying mechanisms remain unclear.

The concomitant use of sodium-glucose co-transporter 2 inhibitors improved the renal outcome of Japanese patients with type 2 diabetes treated with glucagon-like peptide 1 receptor agonists

Aims

This study aimed to clarify the renal influence of glucagon-like peptide 1 receptor agonists (GLP1Ras) with or without sodium-glucose co-transporter 2 inhibitors (SGLT2is) on Japanese patients with type 2 diabetes mellitus (T2DM).

Methods

We retrospectively extracted 547 patients with T2DM who visited the clinics of members of Kanagawa Physicians Association. The progression of albuminuria status and/or a ≥ 15% decrease in the estimated glomerular filtration rate (eGFR) per year was set as the renal composite outcome. Propensity score matching was performed to compare GLP1Ra-treated patients with and without SGLT2i.

Results

After matching, 186 patients in each group were compared. There was no significant difference of the incidence of the renal composite outcomes (17% vs. 20%, P = 0.50); however, the annual decrease in the eGFR was significantly smaller and the decrease in the urine albumin-to-creatinine ratio was larger in GLP1Ra-treated patients with the concomitant use of SGLT2is than in those without it (-1.1 ± 5.0 vs. -2.8 ± 5.1 mL/min/1.73 m2, P = 0.001; and -0.08 ± 0.61 vs. 0.05 ± 0.52, P = 0.03, respectively).

Conclusion

The concomitant use of SGLT2i with GLP1Ra improved the annual decrease in the eGFR and the urine albumin-to-creatinine ratio in Japanese patients with T2DM.

Biology and Clinical Use of Glucagon-Like Peptide-1 Receptor Agonists in Vascular Protection

Glucagon-like peptide-1 receptor agonists (GLP1RA) are incretin agents initially designed for the treatment of type 2 diabetes mellitus but because of pleiotropic actions are now used to reduce cardiovascular disease in people with type 2 diabetes mellitus and in some instances as approved treatments for obesity. In this review we highlight the biology and pharmacology of GLP1RA. We review the evidence for clinical benefit on major adverse cardiovascular outcomes in addition to modulation of cardiometabolic risk factors including reductions in weight, blood pressure, improvement in lipid profiles, and effects on kidney function. Guidance is provided on indications and potential adverse effects to consider. Finally, we describe the evolving landscape of GLP1RA and including novel glucagon-like peptide-1-based dual/polyagonist therapies that are being evaluated for weight loss, type 2 diabetes mellitus, and cardiorenal benefit.

The Utilization of Glucagon-like Peptide 1 Agonists and Risk of Following External Eye Diseases in Type 2 Diabetes Mellitus Individuals: A Population-Based Study

The glucagon-like peptide 1 (GLP-1) agonist showed anti-hyperglycemic and anti-inflammatory effects, which may retard the risk of external eye disease. The protective effect of GLP-1 agonist and dry eye disease (DED) was found, while the relationship between GLP-1 agonist and other corneal diseases was not clear. Herein, we aim to evaluate the association between the usage of GLP-1 agonists and the development of the following external eye disease in type 2 diabetes mellitus (T2DM) patients. A retrospective cohort study using the National Health Insurance Research Database (NHIRD) of Taiwan was conducted. The T2DM patients were divided into those with GLP-1 treatment and those without GLP-1 treatment and matched with a 1:2 ratio. The main outcomes were the development of dry eye disease (DED), superficial keratitis, and infectious keratitis. The Cox proportional hazard regression was adopted to produce the adjusted hazard ratio (aHR) with a 95% confidence interval (CI) of external eye diseases between groups. There were 115, 54, and 11 episodes of DED, superficial keratitis, and infectious keratitis in the GLP-1 group. Another 280, 168, and 31 events of DED, superficial keratitis, and infectious keratitis were recorded in the control group. The GLP-1 group demonstrated a significantly lower incidence of DED (aHR: 0.853, 95% CI: 0.668-0.989, p = 0.0356) and superficial keratitis (aHR: 0.670, 95% CI: 0.475-0.945, p = 0.0107) compared to the control group. In the subgroup analyses, the correlation of GLP-1 agonist and DED development was more prominent in patients younger than 60 years old (p = 0.0018). In conclusion, the GLP-1 agonist treatments are significantly associated with a lower incidence of subsequent DED and superficial keratitis, while the relationship was not significant between GLP-1 agonist usage and infectious keratitis.

Effect of Intestinal Flora on Hyperuricemia-Induced Chronic Kidney Injury in Type 2 Diabetic Patients and the Therapeutic Mechanism of New Anti-Diabetic Prescription Medications

This article examined the current research on hyperuricemia (HUA) exacerbating diabetic kidney damage and novel anti-diabetic medications for treating these people. Hyperuricemia and type 2 diabetes (T2D), both of which are frequent metabolic disorders, are closely connected. Recent studies have shown that hyperuricemia can increase kidney injury in T2D patients by aggravating insulin resistance, by activating the renin-angiotensin-aldosterone system (RAAS), and by stimulating inflammatory factors, and the diversity, distribution, and metabolites of intestinal flora. Considering this, there are just a few of the research examining the effect of hyperuricemia on diabetic kidney injury via intestinal flora. Through the gut-kidney axis, intestinal flora primarily influences renal function. The primary mechanism is that variations in diversity, distribution, and metabolites of intestinal flora led to alterations in metabolites (such as short-chain fatty acids, Indoxyl sulfate and p-cresol sulfate, Trimethylamine N-oxide TMAO). This article reviewed the research and investigates the association between hyperuricemia and T2D, as well as the influence of hyperuricemia on diabetic kidney injury via intestinal flora. In addition, the current novel antidiabetic drugs are discussed, and their characteristics and mechanisms of action are reviewed. These novel antidiabetic drugs include SGLT2 inhibitors, GLP-1 receptor agonists, DDP-4 inhibitors, glucokinase (GK) enzyme activators (GK agonists), and mineralocorticoid receptor antagonists (MRA). Recent studies suggest that these new anti-diabetic medications may have a therapeutic effect on hyperuricemia-induced kidney impairment in diabetes patients via various mechanisms. Some of these medications may reduce blood uric acid levels, while others may improve kidney function by attenuating the overstimulation of RAAS or by decreasing insulin resistance and inflammation in the kidneys. These novel antidiabetic medicines may have a multifaceted approach to treating hyperuricemia-induced kidney impairment in diabetic patients; nevertheless, additional study is required to establish their efficacy and comprehend their specific mechanisms.

Novel Drugs for the Management of Diabetes Kidney Transplant Patients: A Literature Review

The management of diabetes and renal failure is changing thanks to the appearance of new drugs such as glucagon-like peptide 1 receptor agonists (GLP1-RA) and sodium-glucose cotransporter type 2 inhibitors (SGLT2i) that have benefits in terms of survival and cardiorenal protection. Based on the potential mechanisms of GLP1-RA, kidney transplant recipients (KTRs) could benefit from their effects. However, high-quality studies are needed to demonstrate these benefits, in the transplant population, especially those related to cardiovascular benefits and renal protection. Studies with SGLT2i performed in KTRs are much less potent than in the general population and therefore no benefits in terms of patient or graft survival have been clearly demonstrated in this population to date. Additionally, the most frequently observed side effects could be potentially harmful to this population profile, including severe or recurrent urinary tract infections and impaired kidney function. However, benefits demonstrated in KTRs are in line with a known potential effects in cardiovascular and renal protection, which may be essential for the outcome of transplant recipients. Better studies are still needed to confirm the benefits of these new oral antidiabetics in the renal transplant population. Understanding the characteristics of these drugs may be critical for KTRs to be able to benefit from their effects without being damaged. This review discusses the results of the most important published studies on KTRs with GLP1-RA and SGLT2i as well as the potential beneficial effects of these drugs. Based on these results, approximate suggestions for the management of diabetes in KTRs were developed.

Liraglutide abrogates nephrotoxic effects of chemotherapies

Acute kidney injury (AKI) is a common clinical complication. Cisplatin (Cis) is an effective chemotherapeutic drug; however, its acute nephrotoxicity often limits its application. The role of liraglutide (Lir), an agonist of the glucagon-like peptide-1 receptor (GLP-1R), has recently attracted increasing attention beyond glycemic regulation. This study showed that Lir significantly ameliorated Cis-induced kidney dysfunction and renal damage. However, this renoprotective effect was partially abolished in GLP-1R knockout (GLP-1R^-/-) mice. Furthermore, we synthesized Lir metabolites, GLP-1 (9-37) and GLP-1 (28-37), and found that they also exerted reno-protective effects that were not impaired in GLP-1R^-/- mice. We also demonstrated that Lir and its metabolites reduced cisplatin-induced apoptosis in human renal tubular epithelial cells (HK-2). After silencing GLP-1R expression in HK-2 cells with small interfering ribose nucleic acid (siRNA), the protective effect of Lir on HK-2 cells was inhibited, while the protective effects of GLP-1 (9-37) and GLP-1 (28-37) were not affected. Additionally, we demonstrated that Lir and its metabolites inhibited Cis-induced high-mobility group box 1 (HMGB1) nuclear-cytoplasmic translocation and release, and reduced inflammatory cytokines and HMGB1 receptor expression. The exogenous use of recombinant HMGB1 (rHMGB1) dramatically weakened the protective effects of Lir and its metabolites. In conclusion, our study shows that Lir significantly attenuated Cis-induced AKI through GLP-1R dependent and independent pathways, mediated by inhibiting nuclear-cytoplasmic translocation and release of HMGB1. Lir and its metabolites may be effective drugs for treating cisplatin-induced nephrotoxicity.

Renal outcomes with sodium-glucose cotransporters 2 inhibitors

Diabetic nephropathy (DN) is one of the most serious complications of diabetes. Therefore, delaying and preventing the progression of DN becomes an important goal in the clinical treatment of type 2 diabetes mellitus. Recent studies confirm that sodium-glucose cotransporters 2 inhibitors (SGLT2is) have been regarded as effective glucose-lowering drugs with renal protective effect. In this review, we summarize in detail the present knowledge of the effects of SGLT2is on renal outcomes by analyzing the experimental data in preclinical study, the effects of SGLT2is on estimated glomerular flitration rates (eGFRs) and urinary albumin-creatinine ratios (UACRs) from clinical trials and observational studies, and renal events (such as renal death or renal failure requiring renal replacement therapy) in some large prospective cardiovaslucar outcomes trials. The underlying mechanisms for renoprotective activity of SGLT2is have been demondtrated in multiple diabetic and nondiabetic animal models including kidney-specific effects and secondary kidney effects related to amelioration in blood glucose and blood pressure. In conclusion, these promising results show that SGLT2is act beneficially in terms of the kidney for diabetic patients.

Nephroprotective Properties of the Glucose-Dependent Insulinotropic Polypeptide (GIP) and Glucagon-like Peptide-1 (GLP-1) Receptor Agonists

Diabetes mellitus is the leading cause of chronic kidney disease, and about 30–40% of patients with diabetes will develop kidney disease. Incretin hormones have received attention during the past three decades not only as a pharmacotherapy for the treatment of type 2 diabetes, but also for their cardiorenometabolic effects. The main incretins are glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Additional to the pancreas, receptors for GLP-1 are widely distributed in various organs, causing positive effects on endothelial function and vascular atherogenesis. Along with glycemic control and weight reduction, GLP-1 receptor agonists also strongly improve cardiovascular and renal outcomes in patients with type 2 diabetes. Recently, a dual GIP and GLP-1 receptor agonist has been approved for the treatment of type 2 diabetes. Compared to GLP-1 receptor agonist semaglutide, dual GIP and GLP-1 receptor agonist tirzepatide showed a superior reduction in hemoglobin A1c and body weight. Preliminary results also suggest that tirzepatide improves kidney outcomes in adults with type 2 diabetes with increased cardiovascular risk. In this review, we present the nephroprotective properties of dual GIP and GLP-1 receptor agonists as a new drug to treat type 2 diabetes.

Identification of core genes and pathways between geriatric multimorbidity and renal insufficiency: potential therapeutic agents discovered using bioinformatics analysis

Background

Geriatric people are prone to suffer from multiple chronic diseases, which can directly or indirectly affect renal function. Through bioinformatics analysis, this study aimed to identify key genes and pathways associated with renal insufficiency in patients with geriatric multimorbidity and explore potential drugs against renal insufficiency.

Methods

The text mining tool Pubmed2Ensembl was used to detect genes associated with the keywords including "Geriatric", "Multimorbidity" and "Renal insufficiency". The GeneCodis program was used to specify Gene Ontology (GO) biological process terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Protein–protein interaction (PPI) networks were constructed using STRING and visualized in Cytoscape. Module analysis was performed using CytoHubba and Molecular Complex Detection (MCODE) plugins. GO and KEGG analysis of gene modules was performed using the Database for Annotation, Visualization and Integrated Discover (DAVID) platform database. Genes clustered in salient modules were selected as core genes. Then, the functions and pathways of core genes were visualized using ClueGO and CluePedia. Finally, the drug-gene interaction database was used to explore drug-gene interactions of the core genes to identify drug candidates for renal insufficiency in patients with geriatric multimorbidity.

Results

Through text mining, 351 genes associated with "Geriatric", "Multimorbidity" and "Renal insufficiency" were identified. A PPI network consisting of 216 nodes and 1087 edges was constructed and CytoHubba was used to sequence the genes. Five gene modules were obtained by MCODE analysis. The 26 genes clustered in module1 were selected as core candidate genes primarily associated with renal insufficiency in patients with geriatric multimorbidity. The HIF-1, PI3K-Akt, MAPK, Rap1, and FoxO signaling pathways were enriched. We found that 21 of the 26 selected genes could be targeted by 34 existing drugs.

Conclusion

This study indicated that CST3, SERPINA1, FN1, PF4, IGF1, KNG1, IL6, VEGFA, ALB, TIMP1, TGFB1, HGF, SERPINE1, APOA1, APOB, FGF23, EGF, APOE, VWF, TF, CP, GAS6, APP, IGFBP3, P4HB, and SPP1 were key genes potentially involved with renal insufficiency in patients with geriatric multimorbidity. In addition, 34 drugs were identified as potential agents for the treatment and management of renal insufficiency.

Recent Advances in the Emerging Therapeutic Strategies for Diabetic Kidney Diseases

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

Treatment of diabetes mellitus has borne much fruit in the prevention of cardiovascular disease

Cardiovascular (CV) disease is the most alarming complication of diabetes mellitus (DM), and a strategy aiming at cardiovascular event prevention in diabetes mellitus has long been debated. Large landmark clinical trials have shown cardiovascular benefits of intensive glycemic control as a 'legacy effect' in newly diagnosed type 2 diabetes mellitus. In contrast, we have learned that excessive intervention aimed at strong glycemic control could cause unexpected cardiovascular death in patients who are resistant to treatments against hyperglycemia. It has also been shown that the comprehensive multifactorial intervention for cardiovascular risk factors that was advocated in the current guideline provided substantial cardiovascular event reduction. The impact of classical antidiabetic agents launched before 1990s on cardiovascular events is controversial. Although there are many clinical or observational studies assessing the impact of those agents on cardiovascular events, the conclusions are inconsistent owing to variable patient backgrounds and concomitant antidiabetic agents among the studies. Moreover, most of them were not large-scale, randomized, cardiovascular outcome trials. In contrast, GLP-1RA (glucagon-like peptide-1 receptor agonist) and SGLT2 (sodium-glucose cotransporter 2) inhibitors have demonstrated undeniable cardiovascular benefits in large-scale, randomized, controlled trials. Whereas GLP-1RAs decrease atherosclerotic disease, especially stroke, SGLT2 inhibitors mainly prevent heart failure. SGLT2 inhibitors are superior to GLP-1RAs with respect to hard renal outcomes. Therefore, it can be said that drugs such as GLP-1RAs and SGLT2 inhibitors that prevent cardiovascular events, in addition to their glucose-lowering effect, are incredible novel tools that we have gained for use in diabetic treatment.

Update on the management of diabetes in long-term care facilities

The number of patients with diabetes is increasing among older adults in the USA, and it is expected to reach 26.7 million by 2050. In parallel, the percentage of older patients with diabetes in long-term care facilities (LTCFs) will also rise. Currently, the majority of LTCF residents are older adults and one-third of them have diabetes. Management of diabetes in LTCF is challenging due to multiple comorbidities and altered nutrition. Few randomized clinical trials have been conducted to determine optimal treatment for diabetes management in older adults in LTCF. The geriatric populations are at risk of hypoglycemia since the majority are treated with insulin and have different levels of functionality and nutritional needs. Effective approaches to avoid hypoglycemia should be implemented in these settings to improve outcome and reduce the economic burden. Newer medication classes might carry less risk of developing hypoglycemia along with the appropriate use of technology, such as the use of continuous glucose monitoring. Practical clinical guidelines for diabetes management including recommendations for prevention and treatment of hypoglycemia are needed to appropriately implement resources in the transition of care plans in this vulnerable population.

Mechanisms of podocyte injury and implications for diabetic nephropathy

Albuminuria is the hallmark of both primary and secondary proteinuric glomerulopathies, including focal segmental glomerulosclerosis (FSGS), obesity-related nephropathy, and diabetic nephropathy (DN). Moreover, albuminuria is an important feature of all chronic kidney diseases (CKDs). Podocytes play a key role in maintaining the permselectivity of the glomerular filtration barrier (GFB) and injury of the podocyte, leading to foot process (FP) effacement and podocyte loss, the unifying underlying mechanism of proteinuric glomerulopathies. The metabolic insult of hyperglycemia is of paramount importance in the pathogenesis of DN, while insults leading to podocyte damage are poorly defined in other proteinuric glomerulopathies. However, shared mechanisms of podocyte damage have been identified. Herein, we will review the role of haemodynamic and oxidative stress, inflammation, lipotoxicity, endocannabinoid (EC) hypertone, and both mitochondrial and autophagic dysfunction in the pathogenesis of the podocyte damage, focussing particularly on their role in the pathogenesis of DN. Gaining a better insight into the mechanisms of podocyte injury may provide novel targets for treatment. Moreover, novel strategies for boosting podocyte repair may open the way to podocyte regenerative medicine.

Glucagon-Like Peptide-1 Receptor Agonist Use in People Living with Type 2 Diabetes Mellitus and Chronic Kidney Disease: A Narrative Review of the Key Evidence with Practical Considerations

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are incretin-mimetic agents that are effective adjuncts in the treatment of diabetes. This class of medications is also associated with promoting weight loss and a low risk of hypoglycemia, and some have been shown to be associated with a significant reduction of major cardiovascular events. Mounting evidence suggests that GLP-1 RAs have benefits beyond reducing blood glucose that include improving kidney function in people living with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD), a common microvascular complication of T2DM. Several large clinical studies, the majority of which are cardiovascular outcome trials, indicate that GLP-1 RA therapy is safe and tolerable for people living with T2DM and compromised renal function, and also suggest that GLP-1 RAs may have renoprotective properties. Although evidence from clinical trials has shown GLP-1 RAs to be safe and efficacious in people living with T2DM and renal impairment, their use is uncommon in this patient population. With continuing developments in the field of GLP-1 RA therapy, it is important for physicians to understand the benefits and practical use of GLP-1 RAs, as well as the clinical evidence, in order to achieve positive patient outcomes. Here, we review evidence on GLP-1 RA use in people living with T2DM and CKD and summarize renal outcomes from clinical studies. We provide practical considerations for GLP-1 RA use to provide an added benefit to guide treatment in this high-risk patient population.

Effect of the Glucagon-Like Peptide-1 Receptor Agonists Semaglutide and Liraglutide on Kidney Outcomes in Patients With Type 2 Diabetes: Pooled Analysis of SUSTAIN 6 and LEADER

BACKGROUND

We assessed the effect of once-weekly semaglutide and once-daily liraglutide on kidney outcomes in type 2 diabetes.

METHODS

Pooled (n=12 637) and by-trial data from SUSTAIN 6 (Trial to Evaluate Cardiovascular and Other Long-Term Outcomes With Semaglutide in Subjects With Type 2 Diabetes; n=3297) and LEADER (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results; n=9340) were assessed for albuminuria change, annual slope of estimated glomerular filtration rate (eGFR) change, and time to persistent eGFR reduction (30%, 40%, 50%, and 57%) from baseline.

RESULTS

The median follow-up durations were 2.1 years for SUSTAIN 6 and 3.8 years for LEADER. In the pooled analysis, semaglutide/liraglutide lowered albuminuria from baseline to 2 years after randomization by 24% versus placebo (95% CI, 20%-27%; P<0.001). Significant reductions were also observed in by-trial data analyses (P<0.001 for all), the largest being with semaglutide 1.0 mg (33% [95% CI, 24%-40%]; P<0.001) at 2 years. With semaglutide 1.0 mg and liraglutide, eGFR slope decline was significantly slowed by 0.87 and 0.26 mL/min/1.73 m2/y (P<0.0001 and P<0.001), respectively, versus placebo. Effects appeared larger in patients with baseline eGFR <60 versus ≥60 mL/min/1.73 m2 (Pinteraction=0.06 and 0.008 for semaglutide 1.0 mg and liraglutide, respectively). Semaglutide/liraglutide significantly lowered risk of persistent 40% and 50% eGFR reductions versus placebo (hazard ratio [HR], 0.86 [95% CI, 0.75-0.99]; P=0.039 and HR, 0.80 [95% CI, 0.66-0.97]; P=0.023, respectively). Similar, nonsignificant, directional results were observed for 30% and 57% eGFR reductions (HR, 0.92 [95% CI, 0.84-1.02]; P=0.10 and HR, 0.89 [95% CI, 0.69-1.13]; P=0.34). In patients with baseline eGFR 30 to <60 mL/min/1.73 m2, the likelihood of persistent reduction for all thresholds was increased, ranging from HR 0.71 for 30% reduction (95% CI, 0.59-0.85; P=0.0003, Pinteraction=0.017) to 0.54 for 57% reduction (95% CI, 0.36-0.81; P=0.003, Pinteraction=0.035).

CONCLUSIONS

In patients with type 2 diabetes, semaglutide/liraglutide offered kidney-protective effects, which appeared more pronounced in patients with preexisting chronic kidney disease.

Therapeutic peptides: current applications and future directions

Peptide drug development has made great progress in the last decade thanks to new production, modification, and analytic technologies. Peptides have been produced and modified using both chemical and biological methods, together with novel design and delivery strategies, which have helped to overcome the inherent drawbacks of peptides and have allowed the continued advancement of this field. A wide variety of natural and modified peptides have been obtained and studied, covering multiple therapeutic areas. This review summarizes the efforts and achievements in peptide drug discovery, production, and modification, and their current applications. We also discuss the value and challenges associated with future developments in therapeutic peptides.

Glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors for cardiovascular and renal protection: A treatment approach far beyond their glucose-lowering effect

Findings from cardiovascular outcome trials on certain newer glucose-lowering drugs have shown clear cardiovascular and renal benefits. In this review, we provide an updated overview of glucagon-like peptide-1 (GLP-1) receptor agonists and sodium-glucose cotransporter 2 (SGLT-2) inhibitors in terms of cardiovascular and renal protection. Both drugs have been described as diabetes/disease-modifying drugs. There is robust evidence on the benefits of GLP-1 receptor agonists in renal disease and atherosclerotic cardiovascular disease-especially in stroke-which are mainly explained by their antiproteinuric effect. However, this class of drugs has only shown neutral effects on heart failure and further studies are necessary in order to assess their role in this disease. SGLT-2 inhibitors have shown strong benefits in heart failure hospitalizations and renal outcomes, mainly through limiting glomerular filtration rate deterioration, regardless of the presence of diabetes. Nonetheless, their effect on the prevention of major adverse atherosclerotic cardiovascular events and cardiovascular mortality seems to be limited to patients with type 2 diabetes and established cardiovascular disease. Evidence on the cardiovascular and renal benefits of GLP-1 receptor agonists and SGLT-2 inhibitors have significantly modified management plans and treatment choices for patients with type 2 diabetes. There is now a focus on a multifactorial approach that goes beyond the glucose-lowering effect of these drugs, which are the preferred choice in routine clinical practice. According to the current evidence, a patient-focused approach that includes both individualized glycemic control and cardiorenal prevention using GLP-1 receptor agonists and SGLT-2 inhibitors with proven cardiovascular and renal benefits is believed to be the best strategy for achieving the treatment goals of patients with type 2 diabetes. Despite the strong cardiovascular and renal benefits of these drugs, further research is required in order to clarify questions that remain unanswered.

Beneficial effects of liraglutide on peripheral blood vessels

Background/Aim. Macroangiopathy is the major cause of death and disability in type 2 diabetic patients. Studies have shown that liraglutide, a glucagon-like peptide 1 (GLP-1) receptor agonist, can protect cardiovascular system by inhibiting chronic inflammation of diabetes. However, a study about the effects of liraglutide on peripheral blood vessels and peripheral blood leukocytes has not been reported yet. The aim of this study was to determine vasculoprotective effect, vascular protection and mechanism of action of liraglutide in addition to its hypoglycemic effect. Methods. A total of 60 hospitalized patients with type 2 diabetes were recruited from December 2013 to December 2014 at the First Affiliated Hospital of Dalian Medical University, PR China. Before the treatment with liraglutide, height and weight were measured to calculate body mass index (BMI). Blood urea nitrogen (BUN) and so on were detected. Homeostasis model assessment of insulin resistance (HOMA-IR) and islet ? cell function (HOMA-?) were computed. After applying liraglutide for three months, all indexes were measured again. The effects of liraglutide on these indexes were analyzed by paired sample t-test. Results. After the treatment with liraglutide, values of glycosylated hemoglobin ? HbA1c (8.46 ? 1.62 vs. 7.26 ? 1.40%) and 2h postprandial blood glucose ? 2hPBG (11.95 vs. 9.6 mmol/L) decreased significantly (p < 0.05). Body weight (87.3 vs. 82.5 kg) and BMI (30.37 vs. 28.63 kg/m2) decreased by 5.5% and 5.7%, respectively (p < 0.05). Also, levels of triglycerides (TG) (2.57 ? 1.54 vs. 1.81 ? 0.70 mmol/L) and LDL-cholesterol (2.92 ? 0.78 vs. 1.89 ? 0.66 mmol/L) reduced significantly (p < 0.05). Ankle-brachial index (ABI) decreased from 1.24 ? 0.10 to 1.14 ? 0.06 cm/s by 8%, while brachial-ankle pulse wave velocity (ba-PWV) decreased from 1,442.15 ? 196.26 to 1,316.85 ? 146.63 cm/s by 8.7%, and both differences were statistically significant (p < 0.001). Conclusion. Liraglutide, with a good hypoglycemic effect, can significantly reduce postprandial blood glucose and HbA1c, but cannot significantly improve fasting plasma glucose, insulin resistance and islet ? cell function. It also considerably decreased body weight, BMI and TG. Liraglutide can significantly lower ba-PWV and ABI to protect peripheral blood vessels.

Efficacy and Safety of Semaglutide for the Management of Obese Patients With Type 2 Diabetes and Chronic Heart Failure in Real-World Clinical Practice

BACKGROUND

The impact of glucagon-like peptide-1 receptor agonists on patients with heart failure has not been fully described. Our main objective was to evaluate the safety and clinical and glycemic efficacy of once-weekly semaglutide in obese patients with type 2 diabetes and heart failure.

METHODS

In this observational, retrospective, real-world study, we enrolled outpatients with type 2 diabetes, obesity, and heart failure who started semaglutide and were followed-up on at 3, 6, and 12 months.

RESULTS

A total of 136 patients were included. From baseline to 12 months, there was a significant improvement on the Kansas City Cardiomyopathy Questionnaire total symptom score (59.0 ± 24.1 vs 79.9 ± 28.4 points, p<0.01), a reduction in the proportion of patients with New York Heart Association functional class III (40.4% to 16.2%, p<0.01), and a reduction in N-terminal pro-brain natriuretic peptide levels (969.5 ± 653.5 vs 577.4 ± 322.1 pg/mL, p<0.01). Emergency department visits due to heart failure, hospitalizations due to heart failure, and all-cause hospitalizations also declined. Additionally, significant reductions in glycated hemoglobin (-1.4%) and body weight (-12.7 kilograms) were observed as well as a de-intensification of antidiabetic therapy. Moreover, semaglutide was safe and well-tolerated.

CONCLUSION

In obese patients with type 2 diabetes and heart failure, the use of once-weekly semaglutide was safe and clinically efficacious, improving health and functional status. Nevertheless, more strong evidence on glucagon-like peptide-1 receptor agonists in heart failure is required.

Liraglutide protects against lethal renal ischemia-reperfusion injury by inhibiting high-mobility group box 1 nuclear-cytoplasmic translocation and release

Liraglutide, a glucagon-like peptide-1 receptor (GLP-1R) agonist, has been reported to exert protective effects against myocardial, hepatic, and gastric ischemia-reperfusion injury (IRI), but whether it can protect against renal IRI remains unknown. Here, a lethal renal IRI model was established with a 100% mortality rate in untreated mice. Treatment with liraglutide involving a regimen of multiple doses resulted in 100% survival, remarkable preservation of renal function, a significant reduction in pathological damage, and blunted upregulation of TNF-α, IL-1β, IL-6, MCP-1, TLR-2, TLR-4, and RAGE mRNA. We found that liraglutide treatment dramatically inhibited ischemia-induced nucleocytoplasmic translocation and release of HMGB1. This inhibition was associated with a marked decrease (~ 60%) in nuclear histone acetyltransferase activity. In addition, the protective effects of liraglutide on renal IRI were largely abolished by the administration of exogenous HMGB1. When the GLP-1R antagonist exendin (9-39) was given to mice before each liraglutide administration, or GLP-1R-/- mice were used for the renal IRI experiments, the protective effect of liraglutide on renal IRI was partially reversed. Moreover, liraglutide pretreatment significantly inhibited HMGB1 nucleocytoplasmic translocation during hypoxic culture of HK-2 cells in vitro, but the addition of exendin (9-39) significantly eliminated this inhibition. We demonstrate here that liraglutide can exert a strong protective effect on lethal renal IRI in mice. This protection appears to be related to the inhibition of HMGB1 nuclear-cytoplasmic translocation and release and partially depends on GLP-1R. Thus, liraglutide may be therapeutically useful for the clinical prevention and treatment of organ IRI.

Reno-Protective Effect of GLP-1 Receptor Agonists in Type1 Diabetes: Dual Action on TRPC6 and NADPH Oxidases

Diabetic kidney disease (DKD), a serious diabetic complication, results in podocyte loss and proteinuria through NADPH oxidases (NOX)-mediated ROS production. DUOX1 and 2 are NOX enzymes that require calcium for their activation which enters renal cells through the pivotal TRPC channels. Hypoglycemic drugs such as liraglutide can interfere with this deleterious mechanism imparting reno-protection. Herein, we aim to investigate the reno-protective effect of GLP1 receptor agonist (GLP1-RA), via its effect on TRPC6 and NADPH oxidases. To achieve our aim, control or STZ-induced T1DM Sprague-Dawley rats were used. Rats were treated with liraglutide, metformin, or their combination. Functional, histological, and molecular parameters of the kidneys were assessed. Our results show that treatment with liraglutide, metformin or their combination ameliorates DKD by rectifying renal function tests and protecting against fibrosis paralleled by restored mRNA levels of nephrin, DUOX1 and 2, and reduced ROS production. Treatment with liraglutide reduces TRPC6 expression, while metformin treatment shows no effect. Furthermore, TRPC6 was found to be directly interacting with nephrin, and indirectly interacting with DUOX1, DUOX2 and GLP1-R. Our findings suggest that treatment with liraglutide may prevent the progression of diabetic nephropathy by modulating the crosstalk between TRPC6 and NADPH oxidases.

Renoprotective Effects of Incretin-Based Therapy in Diabetes Mellitus

Glucagon-like peptide-1 (GLP-1) receptor agonists are recently discovered antidiabetic drugs with potent hypoglycemic effects. Among different mechanisms of activity, these compounds were shown to reduce blood glucose by suppression of glucagon secretion and stimulation of glucose-dependent insulin secretion. These antidiabetic agents have a minor risk of hypoglycemia and have been suggested as a second-line therapy to be added to metformin treatment to further optimize glycemic control in diabetes. More recently, scientific evidence suggests that GLP-1 receptor agonists may particularly afford protection from diabetic nephropathy through modulation of the molecular pathways involved in renal impairment and so improve renal function. This additional benefit adds further weight for these compounds to become promising drugs not only for glycemic control but also to prevent diabetic complications. In this review, we have updated evidence on the beneficial effects of GLP-1 receptor agonists on diabetic nephropathy and detailed the underlying pathophysiological mechanisms.

Exenatide Attenuates Obesity-Induced Mitochondrial Dysfunction by Activating SIRT1 in Renal Tubular Cells

Saturated free fatty acid (FFA)-induced lipotoxicity plays an important role in obesity-induced kidney injury. Exenatide, a Glucagon-like peptide-1 receptor agonist(GLP-1RA), protects against high-fat diet (HFD)-induced kidney injury. The precise mechanism needs to be further explored. This study investigated whether exenatide protects against FFA-induced tubular epithelial cells (TECs) lipotoxicity and elucidated its underlying mechanisms. Here, we show that exenatide treatment reversed HFD induced TECs injuries, including TECs apoptosis and SIRT1 downregulation. The efficacy of exenatide was better than simvastatin. In palmitate (PA)-stimulated HK2 cells, exenatide treatment reversed the downregulation of SIRT1 and prevented an increase in reactive oxygen species (ROS) production, a decrease in mitochondrial membrane potential, and mitochondrial apoptosis. The renal-protective effects of exenatide on the generation of mitochondrial ROS and mitochondrial apoptosis were blocked by inhibiting SIRT1 activation. Collectively, these findings show that exenatide was superior to simvastatin in the treatment of obesity-TECs injuries, the mechanism is partially through SIRT1 restoration, which directly reverses mitochondrial dysfunction and apoptosis.

Diabetes and kidney disease: emphasis on treatment with SGLT-2 inhibitors and GLP-1 receptor agonists

Kidney disease is a frequent microvascular complication of both type 1 and type 2 diabetes. Historic trials have demonstrated that a tight glycaemic control is the most powerful approach to decrease the chances of developing diabetic nephropathy. However, having an HbA1c < 7% does not completely suppress the risk of kidney disease. The observed residual risk is likely ascribable to two phenomena: 1- the presence of risk factors and alterations additive to and independent of glycaemia, and 2- the activation of long-lasting imbalances by periods of exposure to uncontrolled glycemia, a phenomenon referred to as metabolic memory or legacy effect. Long-lasting oxidative stress, epigenetic alterations, cellular senescence, and the resulting chronic low-grade inflammation are all candidate mechanisms explaining the development of nephropathy despite proper control of risk factors. Recently, two classes of drugs, i.e. glucagon-like peptide (GLP) 1 receptor agonists (RA) and sodium-glucose transporter 2 inhibitors (SGLT-i) have changed this scenario. Indeed, cardiovascular outcome and other trials have clearly shown a renoprotective effect for these drugs, well-beyond their glucose-lowering properties. In this review, we summarize: 1- selected key trials and mechanisms underlying the development of diabetic kidney disease and 2- the results relative to renal endpoints in clinical trials of GLP-1 RA and SGLT-2i. Then, we briefly discuss some of the hypotheses posited to explain the marked renoprotective properties of these two classes, evidencing the still existing gaps in knowledge and proposing future directions to further implement the use of these powerful, disease-modifying drugs.

Diabetic kidney disease in type 2 diabetes: a review of pathogenic mechanisms, patient-related factors and therapeutic options

The global prevalence of diabetic kidney disease is rapidly accelerating due to an increasing number of people living with type 2 diabetes. It has become a significant global problem, increasing human and financial pressures on already overburdened healthcare systems. Interest in diabetic kidney disease has increased over the last decade and progress has been made in determining the pathogenic mechanisms and patient-related factors involved in the development and pathogenesis of this disease. A greater understanding of these factors will catalyse the development of novel treatments and influence current practice. This review summarises the latest evidence for the factors involved in the development and progression of diabetic kidney disease, which will inform better management strategies targeting such factors to improve therapeutic outcomes in patients living with diabetes.

The Role of Cell Division Autoantigen 1 (CDA1) in Renal Fibrosis of Diabetic Nephropathy

The common kidney disease diabetic nephropathy (DN) accounts for significant morbidity and mortality in patients with diabetes, and its effective diagnosis in incipient stages is still lacking. Renal fibrosis is the main pathological feature of DN. Cell division autoantigen 1 (CDA1), a phosphorylated protein encoded by TSPYL2 on the X chromosome, plays a fibrogenic role by modulating the transforming growth factor-β (TGF-β) signaling, but the exact mechanism remains unclear. TGF-β signaling has been recognized as the key factor in promoting the development and progression of DN. At present, strict control of blood sugar and blood pressure can significantly lower the development and progression of DN in the early stages, and many studies have shown that blocking TGF-β signaling can delay the progress of DN. However, TGF-β is a multifunctional cytokine. Its direct intervention may result in increased side effects. Therefore, the targeted intervention of CDA1 not only can block the TGF-β signaling pathway but also can reduce these side effects. In this article, we review the main physiological roles of CDA1, with particular attention to its effect and potential mechanism in the renal fibrosis of DN.

Effect of once-weekly exenatide on estimated glomerular filtration rate slope depends on baseline renal risk: A post hoc analysis of the EXSCEL trial

The effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on renal outcomes in patients with type 2 diabetes at high cardiovascular risk are modest or neutral. However, GLP-1RAs may confer clinical benefits in those at high risk of progressive renal function loss. We examined the effects of once-weekly exenatide (EQW) on estimated glomerular filtration rate (eGFR) slope and urinary albumin:creatinine ratio (UACR) as a function of baseline UACR in 3503 EXSCEL participants (23.7%) with eGFR data available and 2828 participants (19.2%) with UACR change data available. EQW improved eGFR slope assessed via mixed model repeated measures, compared with placebo, in participants with baseline UACR >100 mg/g (0.79 mL/min/1.73 m² /year [95% confidence interval {CI} 0.24-1.34]) and UACR >200 mg/g (1.32 mL/min/1.73 m² /year [95% CI 0.57-2.06]), but not at lower UACR thresholds. EQW reduced UACR, compared with placebo, assessed via analysis of covariance, consistently across subgroups with baseline UACR >30 mg/g (28.2% reduction), baseline UACR >100 mg (22.5% reduction) and baseline UACR >200 mg (34.5% reduction). This post hoc EXSCEL analysis suggests that EQW reduces UACR, with improvement in eGFR slope specifically in participants with elevated baseline UACR.

Exenatide extended release in patients with type 1 diabetes with and without residual insulin production

AIMS

To test whether a long-acting GLP-1 receptor agonist would improve glucose control in patients with type 1 diabetes (T1D) and to determine whether the presence of residual beta cell function would affect the response. In addition, we sought to determine whether the drug would affect beta cell function.

METHODS

We performed a randomized placebo-controlled trial of exenatide extended release (ER) in participants with T1D with and without detectable levels of C-peptide. Seventy-nine participants were randomized to exenatide ER 2 mcg weekly, or placebo, stratified by the presence or absence of detectable C-peptide levels. The primary outcome was the difference in glycated haemoglobin (HbA1c) levels at 24 weeks. Participants were followed for another 6 months off study drug.

RESULTS

At week 24, the time of the primary outcome, the least squares (LS) mean HbA1c level was 7.76% (95% confidence interval [CI] 7.42, 8.10) in the exenatide ER group versus 8.0% (95% CI 7.64, 8.35) in the placebo group (P = 0.08). At week 12 the LS mean HbA1c levels were 7.71% (95% CI 7.37, 8.05) in the exenatide ER group versus 8.05% (95% CI 7.7, 8.4) in the placebo group (P = 0.01). The improvement at week 12 was driven mainly by those with detectable levels of C-peptide. Those treated with exenatide ER lost weight at 12 and 24 weeks compared to those treated with placebo (P <0.001 and P = 0.007). The total insulin dose was lower, but not when corrected for body weight, and was not affected by residual insulin production. Adverse events were more frequent with exenatide ER, but hypoglycaemia was not increased.

CONCLUSION

Treatment with exenatide ER may have short-term benefits in some individuals with T1D who are overweight or who have detectable levels of C-peptide, but short-term improvements were not sustained.

Renal protection with glucagon-like peptide-1 receptor agonists

There is an unmet need for renoprotective drugs for more pronounced reduction of albuminuria beyond that provided by renin-angiotensin system (RAS) blockers and for effective slowdown of eGFR decline independent of albuminuria. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have proven effective in reducing prespecified secondary composite kidney outcomes in cardiovascular outcome trials. However, GLP-1 RAs showed a prevailing anti-albuminuric effect, additional to that of RAS blockers, and a non-significant risk reduction in worsening of kidney function, at variance with sodium-glucose cotransporter 2 inhibitors. Mechanisms underlying renal protection with GLP-1 RAs are porly understood. Though treatment with GLP-1 RAs resulted in better glycaemic, blood pressure and body weight control versus placebo, correction for on-trial changes in these parameters did not significantly affect results. Anti-inflammatory/anti-oxidant effects via intracellular signalling through protein kinase A, natriuretic effect via inhibition of sodium-hydrogen exchanger 3 and reduction of hyperfiltration have been proposed as direct renoprotective effects.

Incretin-based therapies and renin-angiotensin system: Looking for new therapeutic potentials in the diabetic milieu

Incretin-based therapies include pharmacologic agents such as glucagon like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors which exert potent anti-hyperglycemic effects in the diabetic milieu. They are also shown to have extra-pancreatic effects. Renin-angiotensin system is part of the endocrine system which is widely distributed in the body and is closely involved in water and electrolyte homeostasis as well as renal and cardiovascular functions. Hence the renin-angiotensin system is the main target for treating patients with various renal and cardiovascular disorders. There is growing evidence that incretins have modulatory effects on renin-angiotensin system activity; thereby, can be promising therapeutic agents for the management of renal and cardiovascular disorders. But the exact molecular interactions between incretins and renin-angiotensin system are not clearly understood. In this current study, we have reviewed the possible molecular mechanisms by which incretins modulate renin-angiotensin system activity.

Chronic kidney disease as a cardiovascular risk factor

: Chronic kidney disease (CKD) is a public health threat with impact in cardiovascular risk. All forms of cardiovascular disease and mortality are more common in CKD. Treatment of cardiovascular risk factors, hypertension, dyslipidemia and diabetes is essential for cardiovascular and kidney protection. CKD is a marker of high or very high cardiovascular risk and its presence require early treatment and specific goals. Lifestyle is a pivotal factor, stopping smoking, reducing weight in the overweight or obese, starting regular physical exercise and healthy dietary pattern are recommended. Office BP should be lowered towards 130/80 mmHg or even lower if tolerated with sodium restriction and single pill combination, including angiotensin system blocker. Out-of-office BP monitoring, mainly 24-h assessment, is recommended. Diabetes requires treatment from the moment of diagnosis, but prediabetes benefits with lifestyle changes and metformin in patients stage 2 and 3a. iSGLT2 and GLP-1RA are initially recommended in T2D patients with high or very high cardiovascular risk. Concerning dyslipidemia, for patients in stage 4, LDL-C 55 mg/dl or less (1.4 mmol/l) and an LDL-C reduction of 50% or less from baseline is recommended. In stage 3, LDL-C goal is 70 mg/dl or less (1.8 mmol/l) and an LDL-C. reduction of at least 50% from baseline. Statins are the lipid-lowering therapy of choice with or without ezetimibe. Higher doses of statins are required as GFR declines. Available evidence suggests that combined PCSK9 inhibitors with maximally tolerated dose of statins may have an emerging role in treatment of dyslipidemia in CKD patients.

Pathophysiologic mechanisms in diabetic kidney disease: A focus on current and future therapeutic targets

Diabetic kidney disease (DKD) is the primary cause of chronic kidney disease around the globe and is one of the main complications in patients with type 1 and 2 diabetes. The standard treatment for DKD is drugs controlling hyperglycemia and high blood pressure. Renin angiotensin aldosterone system blockade and sodium glucose cotransporter 2 (SGLT2) inhibition have yielded promising results in DKD, but many diabetic patients on such treatments nevertheless continue to develop DKD, leading to kidney failure and cardiovascular comorbidities. New therapeutic options are urgently required. We review here the promising therapeutic avenues based on insights into the mechanisms of DKD that have recently emerged, including mineralocorticoid receptor antagonists, SGLT2 inhibitors, glucagon-like peptide-1 receptor agonist, endothelin receptor A inhibition, anti-inflammatory agents, autophagy activators and epigenetic remodelling. The involvement of several molecular mechanisms in DKD pathogenesis, together with the genetic and epigenetic variability of this condition, makes it difficult to target this heterogeneous patient population with a single drug. Personalized medicine, taking into account the genetic and mechanistic variability, may therefore improve renal and cardiovascular protection in diabetic patients with DKD.

GLP-1 Receptor Agonists and Diabetic Kidney Disease: A Call of Attention to Nephrologists

Type 2 diabetes mellitus (T2DM) represents the main cause of chronic kidney disease (CKD) and end-stage renal disease (ESKD), and diabetic kidney disease (DKD) is a major cause of morbidity and mortality in diabetes. Despite advances in the nephroprotective treatment of T2DM, DKD remains the most common complication, driving the need for renal replacement therapies (RRT) worldwide, and its incidence is increasing. Until recently, prevention of DKD progression was based around strict blood pressure (BP) control, using renin-angiotensin system blockers that simultaneously reduce BP and proteinuria, adequate glycemic control and control of cardiovascular risk factors. Glucagon-like peptide-1 receptor agonists (GLP-1RA) are a new class of anti-hyperglycemic drugs shown to improve cardiovascular and renal events in DKD. In this regard, GLP-1RA offer the potential for adequate glycemic control in multiple stages of DKD without an increased risk of hypoglycemia, preventing the onset of macroalbuminuria and slowing the decline of glomerular filtration rate (GFR) in diabetic patients, also bringing additional benefit in weight reduction, cardiovascular and other kidney outcomes. Results from ongoing trials are pending to assess the impact of GLP-1RA treatments on primary kidney endpoints in DKD.

Glucose and Blood Pressure-Dependent Pathways-The Progression of Diabetic Kidney Disease

The major clinical associations with the progression of diabetic kidney disease (DKD) are glycemic control and systemic hypertension. Recent studies have continued to emphasize vasoactive hormone pathways including aldosterone and endothelin which suggest a key role for vasoconstrictor pathways in promoting renal damage in diabetes. The role of glucose per se remains difficult to define in DKD but appears to involve key intermediates including reactive oxygen species (ROS) and dicarbonyls such as methylglyoxal which activate intracellular pathways to promote fibrosis and inflammation in the kidney. Recent studies have identified a novel molecular interaction between hemodynamic and metabolic pathways which could lead to new treatments for DKD. This should lead to a further improvement in the outlook of DKD building on positive results from RAAS blockade and more recently newer classes of glucose-lowering agents such as SGLT2 inhibitors and GLP1 receptor agonists.

Differential indication for SGLT-2 inhibitors versus GLP-1 receptor agonists in patients with established atherosclerotic heart disease or at risk for congestive heart failure

SGLT-2 inhibitors and most GLP-1 receptor agonists demonstrated cardiovascular superiority and reduction of cardiovascular and overall mortality. These results stand as a turning point in the management of diabetes, shifting the focus from controlling glucose levels to mastering the extra-glycemic effects of these new drugs. This narrative review will discuss recent CVOT with focus on SGLT-2 inhibitors and GLP-1 receptor agonists to distinguish relevant patients' characteristics as potential predictors for therapeutic efficacy. It will also examine their efficacy and safety, the differences in their cardiovascular and renal benefits, aiming to convey clinical suggestions for everyday practice.

Effect of GLP-1 Receptor Agonists in the Cardiometabolic Complications in a Rat Model of Postmenopausal PCOS

Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism and ovulatory dysfunction. Women with PCOS have an elevated prevalence of cardiometabolic risk factors that worsen after menopause. Liraglutide (Lira), a glucagon-like peptide-1 receptor agonist, has shown beneficial metabolic effects in small clinic trials in reproductive-age women with PCOS. We have shown that chronic hyperandrogenemia in an experimental model of postmenopausal PCOS is associated with an adverse cardiometabolic profile and upregulation of the intrarenal renin-angiotensin system (RAS). We analyzed the effect of Lira in the cardiometabolic profile, intrarenal RAS, and blood pressure (BP) in postmenopausal PCOS. Four-week-old female Sprague Dawley rats were treated with DHT or placebo for 17 months. Lira administration during the last 3 weeks caused a bigger reduction in food intake, body weight, fat mass, and homeostasis model assessment of insulin resistance index in PCOS than in control rats. Moreover, Lira improved dyslipidemia and elevated leptin levels in PCOS. In contrast, Lira decreased intrarenal expression of RAS components only in the control group. Lira transiently increased heart rate and decreased BP in control rats. However, Lira did not modify BP but increased heart rate in PCOS. The angiotensin-converting-enzyme inhibitor enalapril abolished the BP differences between PCOS and control rats. However, Lira coadministration with enalapril further reduced BP only in control rats. In summary, Lira has beneficial effects for several cardiometabolic risk factors in postmenopausal PCOS. However, hyperandrogenemia blunted the BP-lowering effect of Lira in postmenopausal PCOS. Androgen-induced activation of intrarenal RAS may play a major role mediating increases in BP in postmenopausal PCOS.