Role of Dapagliflozin and Liraglutide on Diabetes-Induced Cardiomyopathy in Rats: Implication of Oxidative Stress, Inflammation, and Apoptosis

Effect of extracellular matrix stiffness on efficacy of Dapagliflozin for diabetic cardiomyopathy

BACKGROUND

Extracellular matrix (ECM) stiffness is closely related to the progress of diabetic cardiomyopathy (DCM) and the response of treatment of DCM to anti-diabetic drugs. Dapagliflozin (Dapa) has been proven to have cardio-protective efficacy for diabetes and listed as the first-line drug to treat heart failure. But the regulatory relationship between ECM stiffness and treatment efficacy of Dapa remains elusive.

MATERIALS AND METHODS

This work investigated the effect of ECM stiffness on DCM progression and Dapa efficacy using both in vivo DCM rat model and in vitro myocardial cell model with high glucose injury. First, through DCM rat models with various levels of myocardial injury and administration with Dapa treatment for four weeks, the levels of myocardial injury, myocardial oxidative stress, expressions of AT1R (a mechanical signal protein) and the stiffness of myocardial tissues were obtained. Then for mimicking the stiffness of myocardial tissues at early and late stages of DCM, we constructed cell models through culturing H9c2 myocardial cells on the polyacrylamide gels with two stiffness and exposed to a high glucose level and without/with Dapa intervention. The cell viability, reactive oxygen species (ROS) levels and expressions of mechanical signal sensitive proteins were obtained.

RESULTS

The DCM progression is accompanied by the increased myocardial tissue stiffness, which can synergistically exacerbate myocardial cell injury with high glucose. Dapa can improve the ECM stiffness-induced DCM progression and its efficacy on DCM is more pronounced on the soft ECM, which is related to the regulation pathway of AT1R-FAK-NOX2. Besides, Dapa can inhibit the expression of the ECM-induced integrin β1, but without significant impact on piezo 1.

CONCLUSIONS

Our study found the regulation and effect of biomechanics in the DCM progression and on the Dapa efficacy on DCM, providing the new insights for the DCM treatment. Additionally, our work showed the better clinical prognosis of DCM under early Dapa intervention.

PLIN5 Suppresses Lipotoxicity and Ferroptosis in Cardiomyocyte via Modulating PIR/NF-κB Axis

Cardiomyocyte lipotoxicity and ferroptosis are the key to the development of diabetic cardiomyopathy (DCM). Perilipin 5 (PLIN5) is perceived as a significant target of DCM. This study aimed to focus on the role and mechanism of PLIN5 on lipotoxicity and ferroptosis in DCM.Following transfection, mouse cardiomyocytes HL-1 were induced by 0.1 mM palmitic acid (PA) to set up lipotoxic cardiomyocyte models. The cell viability and lipid accumulation were evaluated by cell counting kit-8 assay and Oil red O staining, respectively. Ferrous ion (Fe2+), glutathione (GSH), malondialdehyde (MDA), and reactive oxygen species (ROS) levels were determined to verify the effects of PLIN5 or Pirin (PIR) on ferroptosis. Quantitative real-time reverse transcription polymerase chain reaction or Western blot was performed for quantitative analysis.PLIN5 overexpression promoted the viability, GSH level, and expression of GPX4/PIR/intracellular P65, yet suppressed lipid accumulation, level of Fe2+/MDA/ROS, and expression of interleukin (IL)-1β/IL-18/intranuclear P65 in PA-stimulated HL-1 cells. PIR silencing counteracted the roles of PLIN5 overexpression in PA-stimulated HL-1 cells.PLIN5 suppresses lipotoxicity and ferroptosis in cardiomyocyte via modulating PIR/NF-κB axis, hinting its potential as a therapeutic target in DCM.

Research advances in the anti-inflammatory effects of SGLT inhibitors in type 2 diabetes mellitus

Diabetes mellitus is one of the most significant global burden diseases. It is well established that a chronic, systemic, low-grade inflammatory condition is strongly correlated with type 2 diabetes mellitus (T2D) and the development of target-organ damage (TOD). Sodium-glucose cotransporter inhibitors (SGLTis), novel oral drugs for the treatment of diabetes, act mainly by reducing glucose reabsorption in proximal renal tubules and/or the intestine. Several high-quality clinical trials and large observational studies have revealed that SGLTis significantly improve cardiovascular and renal outcomes in T2D patients. Increasing evidence suggests that this is closely related to their anti-inflammatory properties, which are mainly manifested by a reduction in plasma concentrations of inflammatory biomarkers. This review analyses the potential mechanisms behind the anti-inflammatory effects of SGLTis in diabetes and presents recent evidence of their therapeutic efficacy in treating diabetes and related TOD.

Novel thiazolidin-4-one benzenesulfonamide hybrids as PPARγ agonists: Design, synthesis and in vivo anti-diabetic evaluation

In the current study, two series of novel thiazolidin-4-one benzenesulfonamide arylidene hybrids 9a-l and 10a-f were designed, synthesized and tested in vitro for their PPARɣ agonistic activity. The phenethyl thiazolidin-4-one sulphonamide 9l showed the highest PPARɣ activation % by 41.7%. Whereas, the 3-methoxy- and 4-methyl-4-benzyloxy thiazolidin-4-one sulphonamides 9i, and 9k revealed moderate PPARɣ activation % of 31.7, and 32.8%, respectively, in addition, the 3-methoxy-3-benzyloxy thiazolidin-4-one sulphonamide 10d showed PPARɣ activation % of 33.7% compared to pioglitazone. Compounds 9b, 9i, 9k, 9l, and 10d revealed higher selectivity to PPARɣ over the PPARδ, and PPARα isoforms. An immunohistochemical study was performed in HepG-2 cells to confirm the PPARɣ protein expression for the most active compounds. Compounds 9i, 9k, and 10d showed higher PPARɣ expression than that of pioglitazone. Pharmacological studies were also performed to determine the anti-diabetic activity in rats at a dose of 36 mg/kg, and it was revealed that compounds 9i and 10d improved insulin secretion as well as anti-diabetic effects. The 3-methoxy-4-benzyloxy thiazolidin-4-one sulphonamide 9i showed a better anti-diabetic activity than pioglitazone. Moreover, it showed a rise in blood insulin by 4-folds and C-peptide levels by 48.8%, as well as improved insulin sensitivity. Moreover, compound 9i improved diabetic complications as evidenced by decreasing liver serum enzymes, restoration of total protein and kidney functions. Besides, it combated oxidative stress status and exerted anti-hyperlipidemic effect. Compound 9i showed a superior activity by normalizing some parameters and amelioration of pancreatic, hepatic, and renal histopathological alterations caused by STZ-induction of diabetes. Molecular docking studies, molecular dynamic simulations, and protein ligand interaction analysis were also performed for the newly synthesized compounds to investigate their predicted binding pattern and energies in PPARɣ binding site.

Dapagliflozin mitigates oxidative stress, inflammatory, and histopathological markers of aging in mice

Aging, a complex physiological process affecting all living things, is a major area of research, particularly focused on interventions to slow its progression. This study assessed the antiaging efficacy of dapagliflozin (DAPA) on various aging-related parameters in a mouse model artificially induced to age. Forty male Swiss albino mice were randomly divided into four groups of ten animals each. The control group (Group I) received normal saline. The aging model group (Group II) was administered D-galactose orally at 500mg/kg to induce aging. Following the aging induction, the positive control group received Vitamin C supplementation (Group III), while the DAPA group (Group IV) was treated with dapagliflozin. The inflammatory mediators (TNF-α and IL-1β) showed similar patterns of change. No statistically significant difference was observed between groups III and IV. Both groups had significantly lower values compared to GII, while it was significantly higher compared to GI. Glutathione peroxidase (GSH-Px) showed no statistically significant difference between groups GIII and GIV, but it was higher in GIII compared to GII and significantly lower in GIII compared to GI. The study demonstrated that dapagliflozin exerts a beneficial impact on many indicators of aging in mice. The intervention resulted in a reduction in hypertrophy in cardiomyocytes, an enhancement in skin vitality, a decrease in the presence of inflammatory mediators, and an improvement in the efficacy of antioxidants.

The anti-inflammatory and immunological properties of SGLT-2 inhibitors

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors (SGLT-2i) are antidiabetic oral drugs that act on proximal renal tubules promoting renal glucose excretion. Although SGLT-2i belong to the class of hypoglycemic agents, in the last years great interest has emerged in studying their pleiotropic effects, beyond their ability to lower glucose levels.

PURPOSE

In this review we are describing the anti-inflammatory and immunological properties of SGLT-2i; furthermore, we are addressing how the mechanisms associated with the aforementioned anti-inflammatory properties may contribute to the beneficial effects of SGLT-2i in diabetes.

METHODS

A systematic search was undertaken for studies related the properties of SGLT-2i in reducing the inflammatory milieu of acute and chronic disease by acting on the immune system, independently by glycemia.

RESULTS

Recently, some data described the anti-inflammatory and immunological properties of SGLT-2 in both pre-clinical and clinical studies. Numerous data confirmed the cardio- and -renal protective effects of SGLT-2i in patients with heart failure and kidney diseases, with or without diabetes.

CONCLUSIONS

SGLT-2i are promising drugs with anti-inflammatory and immunological properties. Despite the mechanism of action of SGLT-2i is not fully understood, these drugs demonstrated anti-inflammatory effects, which may help in keeping under control the variety of complications associated with diabetes.

Iron accumulation and lipid peroxidation: implication of ferroptosis in diabetic cardiomyopathy

Diabetic cardiomyopathy (DC) is a serious heart disease caused by diabetes. It is unrelated to hypertension and coronary artery disease and can lead to heart insufficiency, heart failure and even death. Currently, the pathogenesis of DC is unclear, and clinical intervention is mainly symptomatic therapy and lacks effective intervention objectives. Iron overdose mediated cell death, also known as ferroptosis, is widely present in the physiological and pathological processes of diabetes and DC. Iron is a key trace element in the human body, regulating the metabolism of glucose and lipids, oxidative stress and inflammation, and other biological processes. Excessive iron accumulation can lead to the imbalance of the antioxidant system in DC and activate and aggravate pathological processes such as excessive autophagy and mitochondrial dysfunction, resulting in a chain reaction and accelerating myocardial and microvascular damage. In-depth understanding of the regulating mechanisms of iron metabolism and ferroptosis in cardiovascular vessels can help improve DC management. Therefore, in this review, we summarize the relationship between ferroptosis and the pathogenesis of DC, as well as potential intervention targets, and discuss and analyze the limitations and future development prospects of these targets.

Dapagliflozin attenuates cardiac remodeling and dysfunction in rats with β-adrenergic receptor overactivation through restoring calcium handling and suppressing cardiomyocyte apoptosis

Background: Long-term β-adrenergic receptor (β-AR) activation can impair myocardial structure and function. Dapagliflozin (DAPA) has been reported to improve clinical prognosis in heart failure patients, whereas the exact mechanism remains unclear. Here, we investigated the effects of DAPA against β-AR overactivation toxicity and explored the underlying mechanism.Methods and Results: Rats were randomized to receive saline + placebo, isoproterenol (ISO, 5 mg/kg/day, intraperitoneally) + placebo, or ISO + DAPA (1 mg/kg/day, intragastrically) for 2-week. DAPA treatment improved cardiac function, alleviated myocardial fibrosis, prevented cardiomyocytes (CMs) apoptosis, and decreased the expression of ER stress-mediated apoptosis markers in ISO-treated hearts. In isolated CMs, 2-week ISO stimulation resulted in deteriorated kinetics of cellular contraction and relaxation, increased diastolic intracellular Ca2+ level and decay time constant of Ca2+ transient (CaT) but decreased CaT amplitude and sarcoplasmic reticulum (SR) Ca2+ level. However, DAPA treatment prevented abnormal Ca2+ handling and contractile dysfunction in CMs from ISO-treated hearts. Consistently, DAPA treatment upregulated the expression of SR Ca2+-ATPase protein and ryanodine receptor 2 (RyR2) but reduced the expression of phosphorylated-RyR2, Ca2+/calmodulin-dependent protein kinase II (CaMKII), and phosphorylated-CaMKII in ventricles from ISO-treated rats.Conclusion: DAPA prevented myocardial remodeling and cardiac dysfunction in rats with β-AR overactivation via restoring calcium handling and suppressing ER stress-related CMs apoptosis.

New insights into the molecular mechanisms of SGLT2 inhibitors on ventricular remodeling

Ventricular remodeling is a pathological process of ventricular response to continuous stimuli such as pressure overload, ischemia or ischemia-reperfusion, which can lead to the change of cardiac structure and function structure, which is central to the pathophysiology of heart failure (HF) and is an established prognostic factor in patients with HF. Sodium glucose cotransporter 2 inhibitors (SGLT2i) get a new hypoglycemic drug that inhibit sodium glucose coconspirator on renal tubular epithelial cells. Recently, clinical trials increasingly and animal experiments increasingly have shown that SGLT2 inhibitors have been largely applied in the fields of cardiovascular diseases, forinstance heart failure, myocardial ischemia-reperfusion injury, myocardial infarction, atrial fibrillation, metabolic diseases such as obesity, diabetes cardiomyopathy and other diseases play a cardiovascular protective role in addition to hypoglycemic. These diseases are association with ventricular remodeling. Inhibiting ventricular remodeling can improve the readmission rate and mortality of patients with heart failure. So far, clinical trials and animal experiments demonstrate that the protective effect of SGLT2 inhibitors in the cardiovascular field is bound to inhibit ventricular remodeling. Therefore, this review briefly investigates the molecular mechanisms of SGLT2 inhibitors on ameliorating ventricular remodeling, and further explore the mechanisms of cardiovascular protection of SGLT2 inhibitors, in order to establish strategies for ventricular remodeling to prevent the progress of heart failure.

Combination of Empagliflozin and Liraglutide protects heart against isoproterenol-induced myocardial infarction in rats

Cardiovascular benefit of new anti-hyperglycemic agent such as glucagon like peptide-1 receptor agonist (GLP-1RA) or sodium glucose co-transporter-2 inhibitor (SGLT2i) has been proven, with the proposed-mechanism that might be complementary. We investigated the effects of its combination on blood glucose profile and cardiac biomarkers. The rats were given lipid emulsion for 2 weeks, followed by a single dose of streptozotocin (STZ) 35 mg/kg BW, then treated with empagliflozin and/ liraglutide for 30 days while receiving isoproterenol (ISO) 85 mg/kg on day 29 and 30. The results showed no superior improvement on fasting blood glucose (FBG) and insulin sensitivity (KITT) in the combination group compared to empagliflozin/liraglutide group. However, the combination group showed a higher inhibition in almost all biomarkers, specifically against the elevation of CK-MB compared to one of these agents alone. The histopathological examination using H&E staining even showed a minimal inflammation and gap between cardiomyocytes. These findings may indicate the combination of empagliflozin and liraglutide has a better cardiac protection effect.

Oxidative Stress Management in Cardiorenal Diseases: Focus on Novel Antidiabetic Agents, Finerenone, and Melatonin

Oxidative stress is characterized by excessive production of reactive oxygen species together with exhausted antioxidant defenses. This constitutes a main pathophysiologic process that is implicated in cardiovascular and renal diseases. In particular, enhanced oxidative stress may lead to low-density lipoprotein accumulation and oxidation, endothelial cell activation, adhesion molecule overexpression, macrophage activation, and foam cell formation, promoting the development and progression of atherosclerosis. The deleterious kidney effects of oxidative stress are numerous, including podocytopathy, mesangial enlargement, renal hypertrophy, tubulointerstitial fibrosis, and glomerulosclerosis. The prominent role of oxidative mechanisms in cardiorenal diseases may be counteracted by recently developed pharmacotherapies such as novel antidiabetic agents and finerenone. These agents have demonstrated significant antioxidant activity in preclinical and clinical studies. Moreover, the use of melatonin as a treatment in this field has been experimentally investigated, with large-scale clinical studies being awaited. Finally, clinical implications and future directions in this field are presented.

Dapagliflozin Improves Diabetic Cardiomyopathy by Modulating the Akt/mTOR Signaling Pathway

Background

Dapagliflozin can significantly improve heart failure, and Cx43 is one of the molecular mechanisms of heart failure. This study investigated the effect of dapagliflozin on Cx43 and Akt/mTOR signaling pathway in ventricular myocytes.

Methods

A rat model of type 2 diabetes mellitus was established by high-fat diet combined with streptozotocin, and the animals were treated randomly with dapagliflozin. The morphological changes of the myocardium were observed by hematoxylin eosin staining, and the expression and distribution of Cx43 in ventricular myocytes were detected by immunohistochemistry. And Western blot determined the expressions of Cx43, Akt, mTOR, p62, and LC3 proteins in rat myocardium.

Results

Compared with the normal control group, the heart rate of diabetic rats decreased significantly (p < 0.05), QRS wave of ECG widened, and QT interval prolonged (p < 0.05). Dapagliflozin treatment in diabetic rats resulted in improvements in these ECG indexes (p < 0.05) with early administration group obtaining greater efficacy than the late administration group (p < 0.05). In the normal control group, the cardiomyocytes were arranged orderly, and the expression of Cx43 was dense, uniform, and regular, which was higher than that in the intercalated disc. In the diabetic control model group, the cardiomyocytes were enlarged and presented disorderly with detection of Cx43 in the cytoplasm. Early use of dapagliflozin better improved these myocardial tissue lesions. Of note, as diabetic rats exhibited decreased expression of Cx43, Akt, and mTOR (p < 0.05), increased p62 expression (p < 0.05), and decreased LC3-II/I ratio (p < 0.05), administration of dapagliflozin partially reversed the expression of the above proteins (p < 0.05) with greater improvement in the early administration group compared with the late administration group (p < 0.05).

Conclusions

Dapagliflozin increases the expression of Cx43 in cardiomyocytes of diabetic rats and thereby alleviates heart failure partly through regulating the Akt/mTOR signaling pathway.

Dapagliflozin Protects Methamphetamine-Induced Cardiomyopathy by Alleviating Mitochondrial Damage and Reducing Cardiac Function Decline in a Mouse Model

Background: Methamphetamine (METH)-induced cardiovascular toxicity has been attributed to its destructive effect on mitochondrial function at least to some extent. Previous studies highlighted the benefits of dapagliflozin (DAPA) on the cardiovascular system, but the response of METH-induced cardiomyopathy to DAPA is never addressed before. The present study aimed to investigate the potential ability of DAPA in preventing METH-induced cardiomyopathy.

Materials and Methods: C57BL/6 mice were randomly divided into control group (n = 24), METH group (n = 24), and METH + DAPA group (n = 24). The METH-induced cardiomyopathy group received intraperitoneal METH injections at gradually increasing doses thrice weekly for 14 weeks. Mice in the METH + DAPA group were simultaneously treated with DAPA 1 mg/kg/day by intragastric administration. Echocardiography was performed to assess cardiac function. Reactive oxygen species (ROS), JC-1, and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays were performed to evaluate oxidative stress, mitochondrial damage, and apoptosis, respectively. Mitochondrial and apoptosis-related protein expression was measured by western blotting.

Results: Mice exposed to METH exhibited reduced cardiac function (left ventricular ejection fraction [LVEF]: 56.51 ± 6.49 vs. 73.62 ± 1.42, p &lt; 0.01), fibrotic remodeling, and mitochondrial dysfunction, leading to apoptosis (apoptotic cells%: 7.4 ± 1.3 vs. 1.3 ± 0.5, p &lt; 0.01). DAPA significantly reduced mitochondrial dynamics and function, ROS, apoptosis (apoptotic cells%: 2.4 ± 0.8 vs. 7.4 ± 1.3, p &lt; 0.01), cardiac function decline (LVEF: 70.99 ± 4.936 vs. 56.51 ± 6.49, p &lt; 0.01), and fibrotic remodeling. These results indicated that DAPA could be considered as an effective therapeutic agent in the protection against METH-associated cardiomyopathy.

Conclusion: DAPA protects against METH-induced cardiomyopathy in mice by decreasing mitochondrial damage and apoptosis.

Dapagliflozin, Liraglutide, and Their Combination Attenuate Diabetes Mellitus-Associated Hepato-Renal Injury—Insight into Oxidative Injury/Inflammation/Apoptosis Modulation

In this study, we aim to explore the beneficial therapeutic impacts of dapagliflozin (Dapa), a highly potent, reversible, and selective sodium–glucose cotransporter-2 inhibitor, and liraglutide (Lira), a glucagon-like peptide-1 (GLP-1) receptor agonist, as hypoglycaemic agents for the management of diabetes mellitus (DM), as well as their combination against DM-induced complications, including hepato-renal injury. Indeed, the progression of DM was found to be associated with significant hepatic and renal injury, as confirmed by the elevated biochemical indices of hepatic and renal functions, as well as histopathological examination. Dapa, Lira, and their combination effectively attenuated DM-induced hepatic and renal injury, as confirmed by the recovery of hepatic and renal functional biomarkers. The administration of both drugs significantly reduced the tissue contents of MDA and restored the contents of GSH and catalase activity. Moreover, NF-κB and TNF-α expression at the protein and gene levels was significantly reduced in the liver and the kidney. This was in parallel with the significant reduction in the caspase-3 content in the liver and the kidney, as well as suppressed cleaved caspase-3 expression in the hepatic and renal specimens, as confirmed by immune–histochemical analysis. Notably, the combined Dapa/Lira treatment demonstrated an additive superior hepato-renal protective impact compared with the use of either drug alone. Thus, it appears that Dapa and Lira, through the coordinated modulation of oxidative, inflammatory, and apoptotic signalling, confer a significant hepato-renal protective impact against DM-induced complications and tissue injury.