Clinical potential of canagliflozin in cardiovascular risk reduction in patients with type 2 diabetes

Autophagy and mitophagy as potential therapeutic targets in diabetic heart condition: Harnessing the power of nanotheranostics

Autophagy and mitophagy pose unresolved challenges in understanding the pathology of diabetic heart condition (DHC), which encompasses a complex range of cardiovascular issues linked to diabetes and associated cardiomyopathies. Despite significant progress in reducing mortality rates from cardiovascular diseases (CVDs), heart failure remains a major cause of increased morbidity among diabetic patients. These cellular processes are essential for maintaining cellular balance and removing damaged or dysfunctional components, and their involvement in the development of diabetic heart disease makes them attractive targets for diagnosis and treatment. While a variety of conventional diagnostic and therapeutic strategies are available, DHC continues to present a significant challenge. Point-of-care diagnostics, supported by nanobiosensing techniques, offer a promising alternative for these complex scenarios. Although conventional medications have been widely used in DHC patients, they raise several concerns regarding various physiological aspects. Modern medicine places great emphasis on the application of nanotechnology to target autophagy and mitophagy in DHC, offering a promising approach to deliver drugs beyond the limitations of traditional therapies. This article aims to explore the potential connections between autophagy, mitophagy and DHC, while also discussing the promise of nanotechnology-based theranostic interventions that specifically target these molecular pathways.

Mechanisms underlying the vasodilatory effects of canagliflozin in the rabbit thoracic aorta: Involvement of the SERCA pump and Kv channels

AIMS

Canagliflozin is an anti-diabetic agent and sodium glucose co-transporter-2 inhibitor. Despite numerous clinical trials demonstrating its beneficial effects on blood pressure, the cellular mechanisms underlying the effects of canagliflozin on vascular reactivity have yet to be clarified. We investigated the vasodilatory effect of canagliflozin on aortic rings isolated from rabbits.

MAIN METHODS

We used rabbit thoracic aortic rings and its arterial tone was tested by using wire myography system.

KEY FINDINGS

Canagliflozin caused concentration-dependent vasodilation in aortic rings pre-constricted with phenylephrine or high K⁺. However, the degree of canagliflozin-induced vasodilation of the aortic rings pre-constricted with high K⁺ was less than that of rings pre-constricted with phenylephrine. Application of 4-aminopyridine, a voltage-dependent K⁺ (Kv) channel inhibitor, reduced canagliflozin-induced vasodilation. However, pre-incubation of an inwardly rectifying K⁺ channel inhibitor, a large-conductance Ca²⁺-activated K⁺ channel inhibitor, and an ATP-sensitive K⁺ inhibitor did not modulate the vasodilatory effects of canagliflozin. Indeed, canagliflozin increased Kv currents in aortic smooth muscle cells. Pre-treatment with thapsigargin or cyclopiazonic acid, a sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA) pump inhibitors, reduced the vasodilatory effects of canagliflozin. Conversely, pre-treatment with a Ca²⁺ channel inhibitor, adenylyl cyclase/PKA inhibitors, and guanylyl cyclase/PKG inhibitors did not modulate the vasodilatory effects of canagliflozin. Endothelium removal, and pre-treatment with the nitric oxide synthase inhibitor L-NAME, and small- and intermediate-conductance Ca²⁺-activated K⁺ channel inhibitor apamin and TRAM-34, did not diminish the vasodilatory effects of canagliflozin.

SIGNIFICANCE

Our results indicate that canagliflozin induces vasodilation, which is dependent on the robust SERCA activity and Kv channel activation.

Role of Canagliflozin on function of CD34+ve endothelial progenitor cells (EPC) in patients with type 2 diabetes

BACKGROUND

Endothelial progenitor cells (EPCs) has been shown to be dysfunctional in both type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD) leading to poor regeneration of endothelium and renal perfusion. EPCs have been shown to be a robust cardiovascular disease (CVD) risk indicator. Effect of sodium glucose channel inhibitors (SGLT2i) such as Canagliflozin (CG) on a cellular biomarker such as CD34+ve progenitor cells, which may help predict CVD risk, in patients with T2DM with established CKD has not been explored.

METHODS

This is a pilot study where 29 subjects taking metformin and/or Insulin were enrolled in a 16 week, double blind, randomized placebo matched trial, with a low dose 100 mg CG as the intervention group compared to matched placebo. Type 2 diabetes subjects (30-70 years old), with hemoglobin A1c (HbA1c) of 7-10%, were enrolled. CD34+ve cell number, migratory function, gene expression along with vascular parameters such as arterial stiffness, serum biochemistry pertaining to cardio-metabolic health, resting energy expenditure and body composition were measured. Data were collected at week 0, 8 and 16. A mixed model regression analysis was done and p value less than 0.05 was considered statistically significant.

RESULTS

A significant expression of CXCR4 receptor with a concomittant increase in migratory function of CD34+ve cells was observed in CG treated group as compared to placebo group. Gene expression analysis of CD34+ve cells showed an increase in expression of antioxidants (superoxide dismutase 2 or SOD2, Catalase and Glutathione Peroxidase or GPX) and notable endothelial markers (PECAM1, VEGF-A, and NOS3). A significant reduction in glucose and HbA1c levels were observed along with improved systolic and diastolic blood pressure in the CG group. A significant increase in adiponectin (p = 0.006) was also noted in treatment group. Urinary exosomal protein leak in urine, examining podocyte health (podocalyxin, Wilm's tumor and nephrin) showed reduction with CG CONCLUSION: Low dose Canagliflozin has a beneficial effect on CD34+ cell function, serum biochemistry and urinary podocyte specific exosomes in type 2 diabetes.

Canagliflozin: metabolic, cardiovascular and renal protection

Patients with Type 2 Diabetes (T2D) are at risk of developing macrovascular (cardiac, cerebrovascular, peripheral arterial disease) and microvascular (nephropathy, neuropathy, retinopathy) complications. Glycemic control improves only microvascular outcomes. However, some SGLT-2 inhibitors and GLP1-R agonists have proven beneficial in macrovascular conditions. Canagliflozin is an SGLT2 inhibitor that provides sustained reductions in HbA1c, blood pressure and weight. Remarkably, as CANVAS program and CREDENCE trial demonstrated, canagliflozin promotes significant reductions in the frequency of atherosclerotic cardiovascular events, hospitalizations for heart failure and renal outcomes. In addition, real-world studies have confirmed the results of clinical trials in clinical practice. Therefore, canagliflozin should be considered a first-line therapy in the management of T2D patients in order to reduce both micro- and macrovascular complications.

Sodium glucose cotransporter 2 inhibitors: mechanisms of action in heart failure

Diabetes is a key independent risk factor in the development of heart failure (HF) and a strong, adverse prognostic factor in HF patients. HF remains the primary cause of hospitalisation for diabetics and, as previous studies have shown, when HF occurs in these patients, intensive glycaemic control does not directly improve the prognosis. Recent clinical studies assessing a new class of antidiabetic drugs, sodium-glucose cotransporter 2 inhibitors (SGLT2is) showed some unexpected beneficial results. Patients treated with SGLT2is had a significant decrease in both cardiovascular (CV) and all-cause mortality and less hospitalisations due to HF compared to those given a placebo. These significant clinical benefits occurred quickly after the drugs were administered and were not solely due to improved glycaemic control. These groundbreaking clinical trials’ results have already changed clinical practice in the management of patients with diabetes at high CV risk. These trials have triggered numerous experimental studies aimed at explaining the mechanisms of action of this unique group of drugs. This article presents the current state of knowledge about the mechanisms of action of SGLT2is developed for the treatment of diabetes and which, thanks to their cardioprotective effects, may, in the future, become a treatment for patients with HF.

CircRNA-0077930 from hyperglycaemia-stimulated vascular endothelial cell exosomes regulates senescence in vascular smooth muscle cells

Vascular smooth muscle aging leads to diabetic complications such as cardiovascular and kidney diseases or diabetic foot. Therefore, understanding the mechanism of smooth muscle cell senescence in a high-glucose (HG) environment is essential. The purpose of this study was to determine whether and how circRNA from human umbilical vein endothelial cell exosomes (HUVEC-Exos) under HG conditions regulates the senescence of vascular smooth muscle cells (VSMCs). Combining circRNA array analysis and bioinformatics, we postulated that the circRNA-0077930-miR-622-Kras CeRNA network plays an important role in inducing senescence in VSMCs. CircRNA-0077930 transmitted by HG-HUVEs-Exos induced senescence of VSMCs by down-regulation of miR-622 expression and up-regulation of Kras, p21, p53 and p16 expression. Moreover, the lactate dehydrogenase (LDH) activity was significantly increased while anti-oxidative stress marker (superoxide dismutase, SOD) activity was reduced in HG-HUVEC-Exos treatment VSMCs. Finally, HG-HUVEC-Exos with depleted-circRNA-0077930 is no longer able to induce cellular senescence in VSMCs. These findings provided a new light on the effective treatment of VSMC senescence. SIGNIFICANCE OF THE STUDY: Previous studies have shown that endothelial cell senescence is closely related to smooth muscle cell aging. Here, for the first time, we proved that the HG-HUVECs derived exosomes induced the VSMCs senescence by circRNA0077930-miR622-Kras CeRNA network. The circRNA-0077930-depleted exosomes would lose the ability to promote cellular senescence of VSMCs.