Effect of Sodium-Glucose Co-Transporter 2 Inhibitor, Dapagliflozin, on Renal Renin-Angiotensin System in an Animal Model of Type 2 Diabetes

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.

Effects of SGLT2 inhibitors on parameters of renal venous congestion in intrarenal Doppler ultrasonography

Background

Cardiorenal syndrome is a common condition in clinical practice in which renal venous congestion (VC) plays an important role. Intrarenal Doppler ultrasound (IRD) is a non-invasive method to assess and quantify renal VC. The current study aims to investigate the effects of SGLT2 inhibitor (SGLT2i) therapy on IRD parameters of renal VC.

Methods

This prospective observational study included patients with chronic kidney disease (CKD) with or without type 2 diabetes mellitus and/or heart failure (HF) with reduced and preserved ejection fraction who had an indication for standard of care SGLT2i therapy. IRD, assessing venous impedance index (VII), and intrarenal venous flow pattern (IRVF) analysis were performed within the interlobar vessels of the right kidney before and 6 months after initiation of SGLT2i therapy.

Results

A number of 64 patients with CKD and a cardiorenal risk profile were included (mean eGFR 42.9 ml/min/1.73 m2; 56% with HF, and 38% with type 2 diabetes mellitus). 17 patients exhibited signs of VC in the IRD. VII was significantly correlated with levels of NT-proBNP, female gender, NYHA class, and was significantly negative correlated with body mass index. After 6 months, a notable decrease in the mean VII of the right interlobar veins by 0.13 (P < .01) was observed. Stratification according to IRVF pattern showed a significant shift towards reduced renal VC pattern after 6 months (P = .03).

Conclusions

In this study, SGLT2i therapy resulted in a reduction in renal VC as assessed by IRD. These findings underscore the potential haemodynamic benefits of SGLT2 inhibitors in cardiorenal syndrome and warrant further investigation into their clinical implications.

Solution is not simple; sodium-glucose cotransporter-2 inhibitor use in Conn syndrome

PURPOSE

In patients with bilateral primary hyperaldosteronism (PA) and those with unilateral PA who are unwilling or unable to undergo adrenalectomy an increase in plasma renin activity (PRA) provided by mineralocorticoid receptor antagonists (MRAs) therapy reflects sufficient antagonism for elevated aldosterone. Sodium-glucose cotransporter-2 inhibitors (SGLT2-i) have cardiovascular, renal protective properties and some clinical data have shown an increase in PRA levels with SGLT2-i. Here, we present our experience of using SGLT2-i in PA patients with suppressed PRA despite 100 mg/day spironolactone therapy.

CASES

We prospectively evaluate the laboratory values of seven patients who were diagnosed with bilateral hyperaldosteronism. All of them were diabetic and had an HbA1c <7% with metformin treatment alone. Spironolactone was started in all of the patients after diagnosis and although the dose was increased to 100 mg/day, PRA levels remained <1 ng/ml/h. Metformin treatment was changed to empagliflozin in all patients and PRA was checked again at the sixth month of treatment.

RESULTS

Metformin treatment was changed to empagliflozin in all patients and PRA was checked again at the sixth month of treatment. Mean PRA levels were 0.464 ± 0.189 ng/ml/h before the treatment change and increased to mean 3.257 ± 1.881 ng/ml/h in the sixth month ( P  = 0.008). The mean PRA was >1 ng/ml/h except for one patient in the sixth month of treatment.

CONCLUSION

Larger molecular and clinical studies are needed to understand whether the increase in PRA after empagliflozin treatment indicates interference, whether spironolactone treatment has become more effective, or whether empagliflozin has aldosterone receptor antagonism apart from its known effects.

Changes in serum levels of liver-related parameters, uric acid, and hemoglobin in patients with type 2 diabetes mellitus under treatment with tofogliflozin-a post-hoc analysis of the UTOPIA study

Aims/Introduction

The aim of the study was to evaluate the effects of tofogliflozin, a selective sodium-glucose cotransporter 2 inhibitor, on circulating levels of hepatic enzymes, uric acid and hemoglobin levels in patients with type 2 diabetes mellitus (T2DM).

Materials and methods

We evaluated longitudinal changes in circulating aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (γ-GTP), uric acid, and hemoglobin levels in tofogliflozin (n = 169) and conventional treatment groups (n = 170) using data obtained from the UTOPIA trial, a randomized prospective study conducted to evaluate the efficacy of tofogliflozin in preventing atherosclerosis.

Results

Within 104 weeks, tofogliflozin treatment, but not conventional treatment, significantly reduced AST, ALT, and γ-GTP levels. This reduction was significantly greater in the tofogliflozin group than in the conventional group. Stratified analysis showed that, in patients with obesity (defined as body mass index (BMI) ≥ 25.0 kg/m2), significant differences were observed in AST, ALT, and γ-GTP changes from baseline to 104 weeks between treatment groups. However, in patients without obesity, there were no significant differences in AST and γ-GTP changes from baseline to 104 weeks between treatment groups. Multivariable regression analysis showed that changes in BMI and HbA1c levels were independently associated with changes in AST, ALT, and γ-GTP levels. The reduction of uric acid and the increase of hemoglobin from baseline to 104 weeks were significantly greater in the tofogliflozin group than in the conventional group.

Conclusions

The beneficial effects of tofogliflozin on circulating levels of hepatic enzymes, uric acid, and Hb lasted for 2 years in patients with T2DM.

Clinical trial registration

UMIN000017607 (https://www.umin.ac.jp/icdr/index.html).

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-024-00693-x.

Narrative Review of Immunomodulatory and Anti-inflammatory Effects of Sodium-Glucose Cotransporter 2 Inhibitors: Unveiling Novel Therapeutic Frontiers

Sodium-glucose cotransporter 2 inhibitors (SGLT2 inhibitors) have evolved from their initial role as antidiabetic drugs to garner recognition for their remarkable cardio-protective and reno-protective attributes. They have become a crucial component of therapeutic guidelines for congestive heart failure and proteinuric chronic kidney disease (CKD). These benefits extend beyond glycemic control, because improvements in cardiovascular and renal outcomes occur swiftly. Recent studies have unveiled the immunomodulatory properties of SGLT2 inhibitors; thus, shedding light on their potential to influence the immune system and inflammation. This comprehensive review explores the current state of knowledge regarding the impact of SGLT2 inhibitors on the immune system and inflammation, focusing on preclinical and clinical evidence. The review delves into their antiinflammatory and immunomodulating effects, offering insights into clinical implications, and exploring emerging research areas related to their prospective immunomodulatory impact.

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.

Sodium-Glucose Cotransporter Protein 2 Inhibitors: Novel Application for the Treatment of Obesity-Associated Hypertension

Obesity is becoming increasingly prevalent in China and worldwide and is closely related to the development of hypertension. The pathophysiology of obesity-associated hypertension is complex, including an overactive sympathetic nervous system (SNS), activation of the renin-angiotensin-aldosterone system (RAAS), insulin resistance, hyperleptinemia, renal dysfunction, inflammatory responses, and endothelial function, which complicates treatment. Sodium-glucose cotransporter protein 2 (SGLT-2) inhibitors, novel hypoglycemic agents, have been shown to reduce body weight and blood pressure and may serve as potential novel agents for the treatment of obesity-associated hypertension. This review discusses the beneficial mechanisms of SGLT-2 inhibitors for the treatment of obesity-associated hypertension. SGLT-2 inhibitors can inhibit SNS activity, reduce RAAS activation, ameliorate insulin resistance, reduce leptin secretion, improve renal function, and inhibit inflammatory responses. SGLT-2 inhibitors can, therefore, simultaneously target multiple mechanisms of obesity-associated hypertension and may serve as an effective treatment for obesity-associated hypertension.

Cognitive Benefits of Sodium-Glucose Co-Transporters-2 Inhibitors in the Diabetic Milieu

Patients with diabetes are at higher risk of cognitive impairment and memory loss than the normal population. Thus, using hypoglycemic agents to improve brain function is important for diabetic patients. Sodium-glucose cotransporters-2 inhibitors (SGLT2i) are a class of therapeutic agents used in the management of diabetes that has some pharmacologic effects enabling them to fight against the onset and progress of memory deficits. Although the exact mediating pathways are not well understood, emerging evidence suggests that SGLT2 inhibition is associated with improved brain function. This study reviewed the possible mechanisms and provided evidence suggesting SGLT2 inhibitors could ameliorate cognitive deficits.

Antianginal effects of empagliflozin in patients with type 2 diabetes and refractory angina; a randomized, double-blind placebo-controlled trial (EMPT-ANGINA Trial)

INTRODUCTION

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are emerging antidiabetic agents with various potential cardiovascular benefits. The EMPT-ANGINA trial examined the effect of empagliflozin on the angina burden in those with concurrent type 2 diabetes mellitus (T2DM) and refractory angina (RA).

METHOD

In this 8-week, double-blind, randomized, placebo-controlled trial, 75 patients with T2DM and RA were randomly assigned to one of two groups: empagliflozin (n = 37) and placebo (n = 38). The primary outcome was an improvement in angina, which was assessed by the Seattle Angina Questionnaire (SAQ). The secondary outcomes of this study included alterations in the SAQ domains and exercise test components.

RESULTS

The mean age of individuals in the empagliflozin and placebo groups was 67.46 ± 9.4 and 65.47 ± 7.0 years, respectively (p = .304). Patients who received empagliflozin showed a significant improvement in both the primary endpoint, which was the SAQ Summary Score (192.73 ± 20.70 vs. 224 ± 25.36, p < .001) and the secondary endpoints. Exercise test components, including treadmill exercise duration, time till angina, 1 mm ST-segment depression onset, and heart rate (HR) recovery, were all significantly improved in the empagliflozin group. This positive impact was reached with no clinically significant changes in resting and exertion HR or blood pressure. There were no significant side effects in the empagliflozin group (p = .125).

CONCLUSION

Empagliflozin can be safely added as a metabolic modulator agent to existing antianginal medications in individuals with concurrent T2DM and RA to reduce angina symptoms and enhance exercise capacity with minimal side effects.

Pathomechanisms of Diabetic Kidney Disease

The worldwide occurrence of diabetic kidney disease (DKD) is swiftly rising, primarily attributed to the growing population of individuals affected by type 2 diabetes. This surge has been transformed into a substantial global concern, placing additional strain on healthcare systems already grappling with significant demands. The pathogenesis of DKD is intricate, originating with hyperglycemia, which triggers various mechanisms and pathways: metabolic, hemodynamic, inflammatory, and fibrotic which ultimately lead to renal damage. Within each pathway, several mediators contribute to the development of renal structural and functional changes. Some of these mediators, such as inflammatory cytokines, reactive oxygen species, and transforming growth factor β are shared among the different pathways, leading to significant overlap and interaction between them. While current treatment options for DKD have shown advancement over previous strategies, their effectiveness remains somewhat constrained as patients still experience residual risk of disease progression. Therefore, a comprehensive grasp of the molecular mechanisms underlying the onset and progression of DKD is imperative for the continued creation of novel and groundbreaking therapies for this condition. In this review, we discuss the current achievements in fundamental research, with a particular emphasis on individual factors and recent developments in DKD treatment.

Nonsteroidal Mineralocorticoid Receptor Antagonist (Finerenone) in Cardiorenal Disease

Nonsteroidal mineralocorticoid receptor antagonists (MRAs) present a promising therapeutic option in cardiorenal diseases, mitigating the limitations of steroidal MRAs. Finerenone, a third-generation nonsteroidal MRA, has demonstrated beneficial effects in heart failure (HF) and chronic kidney disease (CKD). Clinical trials, including FIDELIO-DKD and FIGARO-DKD, revealed finerenone's efficacy in improving kidney and cardiovascular (CV) outcomes. Patients with CKD and type 2 diabetes (T2DM) on finerenone experienced reduced rates of cardiovascular events, including hospitalization for HF. However, these trials excluded symptomatic HF patients, focusing on asymptomatic or early-stage HF. The ongoing FINEARTS-HF trial evaluates finerenone in HF with preserved ejection fraction (HFpEF). Additionally, studies exploring finerenone and sodium-glucose cotransporter 2 (SGLT2) inhibitors' (Empagliflozin) combination effects in CKD and T2DM (CONFIDENCE) and the selective MR modulator AZD9977 with another SGLT2 inhibitor (dapagliflozin) in HF and CKD (MIRACLE) aim to expand treatment options. While SGLT-2 inhibitors were shown to reduce hyperkalemia risk in FIDELIO-DKD and potentially lower new-onset HF incidence in FIGARO-DKD, further research is essential. So far, the evidence for the beneficial effect of finerenone in the spectrum of cardiorenal diseases is based only on the results of studies conducted in patients with T2DM, and clinical trials of finerenone in patients with nondiabetic kidney disease are ongoing. Nonsteroidal MRAs hold significant potential as pivotal treatment targets across the cardiorenal disease spectrum. This review will focus on the effects of finerenone on cardiorenal disease.

The Impact of SGLT2 Inhibitors in the Heart and Kidneys Regardless of Diabetes Status

Chronic Kidney Disease (CKD) and Cardiovascular Disease (CVD) are two devastating diseases that may occur in nondiabetics or individuals with diabetes and, when combined, it is referred to as cardiorenal disease. The impact of cardiorenal disease on society, the economy and the healthcare system is enormous. Although there are numerous therapies for cardiorenal disease, one therapy showing a great deal of promise is sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors. The SGLT family member, SGLT2, is often implicated in the pathogenesis of a range of diseases, and the dysregulation of the activity of SGLT2 markedly effects the transport of glucose and sodium across the luminal membrane of renal cells. Inhibitors of SGLT2 were developed based on the antidiabetic action initiated by inhibiting renal glucose reabsorption, thereby increasing glucosuria. Of great medical significance, large-scale clinical trials utilizing a range of SGLT2 inhibitors have demonstrated both metabolic and biochemical benefits via numerous novel mechanisms, such as sympathoinhibition, which will be discussed in this review. In summary, SGLT2 inhibitors clearly exert cardio-renal protection in people with and without diabetes in both preclinical and clinical settings. This exciting class of inhibitors improve hyperglycemia, high blood pressure, hyperlipidemia and diabetic retinopathy via multiple mechanisms, of which many are yet to be elucidated.

A systematic review on renal effects of SGLT2 inhibitors in rodent models of diabetic nephropathy

We have performed a systematic review of studies reporting on the renal effects of SGLT2 inhibitors in rodent models of diabetes. In 105 studies, SGLT2 inhibitors improved not only the glycemic control but also various aspects of renal function in most cases. These nephroprotective effects were similarly reported whether treatment with the SGLT2 inhibitor started concomitant with the onset of diabetes (within 1 week), early after onset (1-4 weeks) or after nephropathy had developed (>4 weeks after onset) with the latter probably having the greatest translational value. They were observed across various animal models of type 1 and type 2 diabetes/obesity (4 and 23 models, respectively), although studies in the type 2 diabetes model of db/db mice more often had negative data than in other models. Among possibly underlying pathophysiological mechanisms of nephroprotection, treatment with SGLT2 inhibitors had beneficial effects on lipid metabolism, blood pressure, glomerulosclerosis as well as renal tubular fibrosis, apoptosis, oxidative stress, and inflammation. These pathomechanisms highly influence atherosclerosis and renal health, which are two major factors that lead to an enhanced mortality in patients with diabetes and/or chronic kidney disease. Interestingly, renal SGLT2 inhibitor effects did not always correlate with those on glucose homeostasis, particularly in a limited number of direct comparative studies with other anti-diabetic treatments, indicating that nephroprotection may at least partly occur by mechanisms other than improving glycemic control. Our analyses did not provide evidence for different nephroprotective efficacy between SGLT2 inhibitors. Importantly, only four of 105 studies reported on female animals, and none provided direct comparative data between sexes. We conclude that more data on female animals and more direct comparative studies with other anti-diabetic compounds and combinations of treatments are needed.

Repurposing Drugs for Diabetes Mellitus as Potential Pharmacological Treatments for Sarcopenia - A Narrative Review

Sarcopenia, the age-related loss of muscle strength and mass or quality, is a common condition with major adverse consequences. Although the pathophysiology is incompletely understood, there are common mechanisms between sarcopenia and the phenomenon of accelerated ageing seen in diabetes mellitus. Drugs currently used to treat type 2 diabetes mellitus may have mechanisms of action that are relevant to the prevention and treatment of sarcopenia, for those with type 2 diabetes and those without diabetes. This review summarises shared pathophysiology between sarcopenia and diabetes mellitus, including the effects of advanced glycation end products, mitochondrial dysfunction, chronic inflammation and changes to the insulin signalling pathway. Cellular and animal models have generated intriguing, albeit mixed, evidence that supports possible beneficial effects on skeletal muscle function for some classes of drugs used to treat diabetes, including metformin and SGLT2 inhibitors. Most human observational and intervention evidence for the effects of these drugs has been derived from populations with type 2 diabetes mellitus, and there is a need for intervention studies for older people with, and at risk of, sarcopenia to further investigate the balance of benefit and risk in these target populations. Not all diabetes treatments will be safe to use in those without diabetes because of variable side effects across classes. However, some agents [including glucagon-like peptide (GLP)-1 receptor agonists and SGLT2 inhibitors] have already demonstrated benefits in populations without diabetes, and it is these agents, along with metformin, that hold out the most promise for further investigation in sarcopenia.

Luseogliflozin and caloric intake restriction increase superoxide dismutase 2 expression, promote antioxidative effects, and attenuate aortic endothelial dysfunction in diet-induced obese mice

AIMS/INTRODUCTION

The mechanisms underlying the effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors on aortic endothelial dysfunction in diet-induced obesity are not clearly understood. This study investigated whether SGLT2 inhibition by luseogliflozin improved free fatty acid (FFA)-induced endothelial dysfunction in high-fat diet (HFD)-induced obese mice.

MATERIALS AND METHODS

Mice were fed a control diet or high-fat diet for 8 weeks, and then each diet with or without luseogliflozin was provided for an additional 8 weeks under free or paired feeding. Afterward, the thoracic aortas were removed and utilized for the experiments.

RESULTS

Luseogliflozin treatment decreased body weight, fasting blood glucose, insulin, and total cholesterol in HFD-fed mice only under paired feeding but not under free feeding. Endothelial-dependent vasodilation under FFA exposure conditions was significantly lower in HFD-fed mice than in control diet-fed mice, and luseogliflozin treatment ameliorated FFA-induced endothelial dysfunction. Reactive oxygen species (ROS) production induced by FFA was significantly increased in HFD-induced obese mice. Luseogliflozin treatment increased the expression of superoxide dismutase 2 (SOD2), an antioxidative molecule, and reduced FFA-induced ROS production in the thoracic aorta. Superoxide dismutase reversed FFA-induced endothelial dysfunction in HFD-fed mice.

CONCLUSIONS

It was shown that caloric restriction is important for the effect of luseogliflozin on metabolic parameters and endothelial dysfunction. Furthermore, SGLT2 inhibition by luseogliflozin possibly ameliorates FFA-induced endothelial dysfunction by increasing SOD2 expression and decreasing reactive oxygen species production in the thoracic aorta.

SGLT2 Inhibitor—Dapagliflozin Attenuates Diabetes-Induced Renal Injury by Regulating Inflammation through a CYP4A/20-HETE Signaling Mechanism

Diabetic kidney disease (DKD) is a serious complication of diabetes, affecting millions of people worldwide. Inflammation and oxidative stress are key contributors to the development and progression of DKD, making them potential targets for therapeutic interventions. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have emerged as a promising class of drugs, with evidence demonstrating that they can improve renal outcomes in people with diabetes. However, the exact mechanism by which SGLT2i exert their renoprotective effects is not yet fully understood. This study demonstrates that dapagliflozin treatment attenuates renal injury observed in type 2 diabetic mice. This is evidenced by the reduction in renal hypertrophy and proteinuria. Furthermore, dapagliflozin decreases tubulointerstitial fibrosis and glomerulosclerosis by mitigating the generation of reactive oxygen species and inflammation, which are activated through the production of CYP4A-induced 20-HETE. Our findings provide insights onto a novel mechanistic pathway by which SGLT2i exerts their renoprotective effects. Overall, and to our knowledge, the study provides critical insights into the pathophysiology of DKD and represents an important step towards improving outcomes for people with this devastating condition.

Impact of Sodium-Glucose Cotransporter-2 Inhibitors on Cardiac Bioenergetic Properties and Cardiorespiratory Fitness: A Special Effect of SGLT2i In Heart Failure?

Recent clinical trials have highlighted the profound benefits of sodium-glucose linked transporter 2 inhibitors (SGLT2i) on cardiovascular mortality and hospitalization for heart failure patients. Modest improvements in glycemic, lipid, or blood pressure control are unlikely to contribute to these significant beneficial outcomes, generating much interest in the relevant mechanisms leading to outcome improvements. In this review, we discuss the current evidence supporting a shift in myocardial substrate utilization from carbohydrates and fat oxidation toward energy efficient ketone bodies in the failing heart and the role of SGLT2i in this key metabolic adaptation to optimize myocardial fuel energetics. Further insights into the effect of SGLT2i on the indices of cardiorespiratory fitness are outlined and provide important clues into their mechanism of benefit. This mechanistic discussion in the context of recent trials of SGLT2i denotes a promising treatment paradigm of heart failure in individuals with and without diabetes.

Sodium-glucose cotransporter inhibitors and kidney fibrosis: review of the current evidence and related mechanisms

Sodium-glucose cotransporter inhibitors (SGLT2i) are a new class of anti-diabetic drugs that have beneficial cardiovascular and renal effects. These drugs decrease proximal tubular glucose reabsorption and decrease blood glucose levels as a main anti-diabetic action. Furthermore, SGLT2i decreases glomerular hyperfiltration by a tubuloglomerular feedback mechanism. However, the renal benefits of these agents are independent of glucose-lowering and hemodynamic factors, and SGLT2i also impacts the kidney structure including kidney fibrosis. Renal fibrosis is a common pathway and pathological marker of virtually every type of chronic kidney disease (CKD), and amelioration of renal fibrosis is of utmost importance to reduce the progression of CKD. Recent studies have shown that SGLT2i impact many cellular processes including inflammation, hypoxia, oxidative stress, metabolic functions, and renin-angiotensin system (RAS) which all are related with kidney fibrosis. Indeed, most but not all studies showed that renal fibrosis was ameliorated by SGLT2i through the reduction of inflammation, hypoxia, oxidative stress, and RAS activation. In addition, less known effects on SGLT2i on klotho expression, capillary rarefaction, signal transducer and activator of transcription signaling and peptidylprolyl cis/trans isomerase (Pin1) levels may partly explain the anti-fibrotic effects of SGLT2i in kidneys. It is important to remember that some studies have not shown any beneficial effects of SGLT2i on kidney fibrosis. Given this background, in the current review, we have summarized the studies and pathophysiologic aspects of SGL2 inhibition on renal fibrosis in various CKD models and tried to explain the potential reasons for contrasting findings.

Links between Metabolic Syndrome and Hypertension: The Relationship with the Current Antidiabetic Drugs

Hypertension poses a significant burden in the general population, being responsible for increasing cardiovascular morbidity and mortality, leading to adverse outcomes. Moreover, the association of hypertension with dyslipidaemia, obesity, and insulin resistance, also known as metabolic syndrome, further increases the overall cardiovascular risk of an individual. The complex pathophysiological overlap between the components of the metabolic syndrome may in part explain how novel antidiabetic drugs express pleiotropic effects. Taking into consideration that a significant proportion of patients do not achieve target blood pressure values or glucose levels, more efforts need to be undertaken to increase awareness among patients and physicians. Novel drugs, such as incretin-based therapies and renal glucose reuptake inhibitors, show promising results in decreasing cardiovascular events in patients with metabolic syndrome. The effects of sodium-glucose co-transporter-2 inhibitors are expressed at different levels, including renoprotection through glucosuria, natriuresis and decreased intraglomerular pressure, metabolic effects such as enhanced insulin sensitivity, cardiac protection through decreased myocardial oxidative stress and, to a lesser extent, decreased blood pressure values. These pleiotropic effects are also observed after treatment with glucagon-like peptide-1 receptor agonists, positively influencing the cardiovascular outcomes of patients with metabolic syndrome. The initial combination of the two classes may be the best choice in patients with type 2 diabetes mellitus and multiple cardiovascular risk factors because of their complementary mechanisms of action. In addition, the novel mineralocorticoid receptor antagonists show significant cardio-renal benefits, as well as anti-inflammatory and anti-fibrotic effects. Overall, the key to better control of hypertension in patients with metabolic syndrome is to consider targeting multiple pathogenic mechanisms, using a combination of the different therapeutic agents, as well as drastic lifestyle changes. This article will briefly summarize the association of hypertension with metabolic syndrome, as well as take into account the influence of antidiabetic drugs on blood pressure control.

Heart Failure And Type 2 Diabetes Mellitus: Neurohumoral, Histological And Molecular Interconnections

Heart failure (HF) is a global healthcare burden and a leading cause of morbidity and mortality worldwide. Type 2 diabetes mellitus (T2DM) appears to be one of the major risk factors that significantly worsen HF prognosis and increase the risk of fatal cardiovascular outcomes. Despite a great knowledge of pathophysiological mechanisms involved in HF development and progression, hospitalization rates in patients with HF and concomitant T2DM remain elevated. In this review, we discuss the complex interplay between systemic neurohumoral regulation and local cardiac mechanisms participating in myocardial remodeling and HF development in T2DM with special attention to cardiomyocyte energy metabolism, mitochondrial function and calcium metabolism, cardiomyocyte hypertrophy and death, extracellular matrix remodeling.

The Neuronal and Non-Neuronal Pathways of Sodium-Glucose Cotransporter-2 Inhibitor on Body Weight-Loss and Insulin Resistance

With the emergence of sodium-glucose cotransporter 2 inhibitors (SGLT2i), the treatment of type 2 diabetes mellitus (T2DM) has achieved a new milestone, of which the insulin-independent mechanism could produce weight loss, improve insulin resistance (IR) and exert other protective effects. Besides the well-acknowledged biochemical processes, the dysregulated balance between sympathetic and parasympathetic activity may play a significant role in IR and obesity. Weight loss caused by SGLT-2i could be achieved via activating the liver-brain-adipose neural axis in adipocytes. We previously demonstrated that SGLT-2 are widely expressed in central nervous system (CNS) tissues, and SGLT-2i could inhibit central areas associated with autonomic control through unidentified pathways, indicating that the role of the central sympathetic inhibition of SGLT-2i on blood pressure and weight loss. However, the exact pathway of SGLT2i related to these effects and to what extent it depends on the neural system are not fully understood. The evidence of how SGLT-2i interacts with the nervous system is worth exploring. Therefore, in this review, we will illustrate the potential neurological processes by which SGLT2i improves IR in skeletal muscle, liver, adipose tissue, and other insulin-target organs via the CNS and sympathetic nervous system/parasympathetic nervous system (SNS/PNS).

Role of hypoxia inducible factor/vascular endothelial growth factor/endothelial nitric oxide synthase signaling pathway in mediating the cardioprotective effect of dapagliflozin in cyclophosphamide-induced cardiotoxicity

BACKGROUND

Cyclophosphamide (CP) is a commonly used chemotherapeutic and immunosuppressive alkylating agent. However, cardiac adverse effects of CP interfere with its clinical benefit. Cardio-oncology research is currently an important issue and finding effective cardiopreserving agents is a critical need. For the first time, we aimed to detect if dapagliflozin (DAP) could ameliorate CP-induced cardiac injury and investigated the role of hypoxia inducible factor α (HIF1α)/vascular endothelial growth factor (VEGF)/endothelial nitric oxide synthase (eNOS) pathway.

METHODS

Forty male Wistar albino rats were included in the current model. Studied groups are: control group; CP-induced cardiotoxicity group; CP group treated with DAP; CP group treated with DAP and administered a nitric oxide synthase inhibitor; nitro-ω-L-arginine (L-NNA) before DAP to explore the role of eNOS.

RESULTS

Our data revealed that CP could induce cardiac damage as manifested by significant increases in cardiac enzymes, blood pressure, malondialdehyde (MDA), tumor necrosis factor alpha (TNFα), HIF1α, sodium glucose co-transporter 2 (SGLT2) and cleaved caspase-3 levels with toxic histopathological changes. However, there are significant decreases in reduced glutathione (GSH), total antioxidant capacity (TAC), VEGF, and eNOS. On the opposite side, co-administration of DAP showed marked improvement of CP-induced cardiac damage that may be due to its ability to inhibit SGLT2, antioxidant, anti-inflammatory and anti-apoptotic properties. Results showed decreasing the cardioprotective effect of DAP on administration of L-NNA, reflecting the critical effect of eNOS in mediating such protection.

CONCLUSION

DAP could reduce CP cardiotoxicity based upon its ability to modulate SGLT2 and HIF1α/VEGF/eNOS signaling pathway.

Obesity-associated cardiometabolic complications in polycystic ovary syndrome: The potential role of sodium-glucose cotransporter-2 inhibitors

Polycystic Ovary Syndrome (PCOS) is the most common endocrine disorder in reproductive-age women. PCOS is characterized by androgen excess, oligo/anovulation, and polycystic appearance of the ovaries. Women with PCOS have an increased prevalence of multiple cardiovascular risk factors such as insulin resistance, hypertension, renal injury, and obesity. Unfortunately, there is a lack of effective, evidence-based pharmacotherapeutics to target these cardiometabolic complications. Sodium-glucose cotransporter-2 (SGLT2) inhibitors provide cardiovascular protection in patients with and without type 2 diabetes mellitus. Although the exact mechanisms of how SGLT2 inhibitors confer cardiovascular protection remains unclear, numerous mechanistic hypotheses for this protection include modulation of the renin-angiotensin system and/or the sympathetic nervous system and improvement in mitochondrial function. Data from recent clinical trials and basic research show a potential role for SGLT2 inhibitors in treating obesity-associated cardiometabolic complications in PCOS. This narrative review discusses the mechanisms of the beneficial effect of SGLT2 inhibitors in cardiometabolic diseases in PCOS.

Body fluid regulation via chronic inhibition of sodium-glucose cotransporter-2 in patients with heart failure: a post hoc analysis of the CANDLE trial

BACKGROUND

In patients with chronic heart failure (CHF) and type 2 diabetes (T2D), sodium-glucose cotransporter-2 (SGLT2) inhibition improves cardiorenal outcomes, but details of the effects on distinct subsets of body fluid volume remain incomplete.

METHODS

This was a post hoc analysis of patients with CHF and T2D in the CANDLE trial (UMIN000017669), an investigator-initiated, multi-center, randomized open-label trial that compared the effect of canagliflozin (100 mg, n = 113) with glimepiride (starting dose: 0.5 mg, n = 120) on changes in N-terminal pro-brain natriuretic peptide. The estimated plasma volume (ePV, calculated with the Straus formula) and estimated extracellular volume (eEV, determined by the body surface area) were compared between treatment groups at weeks 4, 12, and 24.

RESULTS

Among 233 patients analyzed, 166 (71.2%) had an ejection fraction (EF) > 50%. Reductions in ePV and eEV were observed only in the canagliflozin group until week 12 (change from baseline at week 12, ePV; - 7.63%; 95% confidence interval [CI], - 10.71 to - 4.55%, p < 0.001, eEV; - 123.15 mL; 95% CI, - 190.38 to - 55.92 mL, p < 0.001). While ePV stopped falling after week 12, eEV continued to fall until week 24 ([change from baseline at week 24] - [change from baseline at week 12], ePV; 1.01%; 95%CI, - 2.30-4.32%, p = 0.549, eEV; - 125.15 mL; 95% CI, - 184.35 to - 65.95 mL, p < 0.001).

CONCLUSIONS

Maintenance of a modest reduction in ePV and continuous removal of eEV via chronic SGLT2 inhibition suggests that favorable body fluid regulation contributes to the cardiorenal benefits of SGLT2 inhibitors in patients with CHF, irrespective of EF.

TRIAL REGISTRATION

UMIN000017669.

Pleiotropic effect of sodium-glucose cotransporter 2 inhibitors on blood pressure

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been incorporated as guideline-directed medical therapy for heart failure with reduced ejection fraction. Recent trials clearly established the efficacy of SGLT2 inhibitors on cardiac remodeling while preventing renal function decline in patients with or without diabetes mellitus. Blood pressure reduction during SGLT2 inhibitors use has been proposed through pleiotropic pathways and as a potential contributor that translates to cardiovascular benefits. The mechanisms underlying this decrease in blood pressure are not simply glycemic control. Orchestrating fluid status, modulation of sodium content and renin-angiotensin-activation system, anti-fibrosis and anti-inflammatory effect, ameliorating the characteristics of metabolic syndrome, as well as restoration of circadian rhythm all contributed to the BP lowering effect by SGLT2 inhibitors. Although SGLT2 inhibitors has not been demonstrated as anti-hypertensive agents thus far, their effects on BP alteration are clinically significant. In this review, we revisited the evidence correlating SGLT2 inhibitor use with blood pressure level. Future research directions will focus on the signaling pathway of SGLT2 inhibitors for fluid removal, atherosclerosis, vasoconstriction, and eventually hypertension.

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.

Effect of sodium-glucose cotransporter-2 inhibitors on aldosterone and renin levels in diabetes mellitus type 2 patients: a systematic review and meta-analysis

The effect of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on plasma aldosterone concentration (PAC) and plasma renin activity (PRA) levels are still inconclusive. This meta-analysis aimed to demonstrate the changes in PAC and PRA levels after the use of SGLT2i in type 2 diabetes patients. A search for relevant publications was performed using PubMed/Medline, Scopus, Cochrane, and Embase databases from their inception through May 2022. Inclusion criteria were studies that contained data on crude PAC and PRA levels before and after the use of SGLT2i in adult type 2 diabetes patients. Standardized mean difference (SMD) with a 95% confidence interval (95% CI) was calculated. Data was separately analyzed by study design: randomized controlled study (RCT) and non-randomized controlled study (non-RCT). Ten studies involving 380 patients were included with two RCT and eight non-RCT. Serum PAC levels showed no significant change after the use of SGLT2i in both RCT and non-RCT. Significantly higher PRA levels were observed after the use of SGLT2i in both RCT and non-RCT with SMD of 0.40 ng/mL/hr; 95% CI (0.06, 0.74) and SMD of 0.36 ng/mL/hr; 95%CI (0.17, 0.55), respectively. Subgroup analysis found significantly higher PRA levels after the use of SGLT2i (SMD 0.45 ng/mL/hr; 95% CI (0.18, 0.71)) only in subgroups that used for three months or less. The use of SGLT2i in diabetes mellitus type 2 patients can affect PRA levels, especially during short-term use. PRA levels should be interpreted with caution in this population.

Enhanced Cardiorenal Protective Effects of Combining SGLT2 Inhibition, Endothelin Receptor Antagonism and RAS Blockade in Type 2 Diabetic Mice

Treatments with sodium-glucose 2 cotransporter inhibitors (SGLT2i) or endothelin receptor antagonists (ERA) have shown cardiorenal protective effects. The present study aimed to evaluate the cardiorenal beneficial effects of the combination of SGLT2i and ERA on top of renin-angiotensin system (RAS) blockade. Type 2 diabetic mice (db/db) were treated with different combinations of an SGLT2i (empagliflozin), an ERA (atrasentan), and an angiotensin-converting enzyme inhibitor (ramipril) for 8 weeks. Vehicle-treated diabetic mice and non-diabetic mice were included as controls. Weight, blood glucose, blood pressure, and kidney and heart function were monitored during the study. Kidneys and heart were collected for histological examination and to study the intrarenal RAS. Treatment with empagliflozin alone or combined significantly decreased blood glucose compared to vehicle-treated db/db. The dual and triple therapies achieved significantly greater reductions in diastolic blood pressure than ramipril alone. Compared to vehicle-treated db/db, empagliflozin combined with ramipril or in triple therapy significantly prevented GFR increase, but only the triple combination exerted greater protection against podocyte loss. In the heart, empagliflozin alone or combined reduced cardiac isovolumetric relaxation time (IVRT) and left atrium (LA) diameter as compared to vehicle-treated db/db. However, only the triple therapy was able to reduce cardiomyocyte area. Importantly, the add-on triple therapy further enhanced the intrarenal ACE2/Ang(1-7)/Mas protective arm of the RAS. These data suggest that triple therapy with empagliflozin, atrasentan and ramipril show synergistic cardiorenal protective effects in a type 2 diabetic mouse model.

Repurposing SGLT2 Inhibitors for Neurological Disorders: A Focus on the Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a substantially increasing incidence rate. It is characterized by repetitive behavior, learning difficulties, deficits in social communication, and interactions. Numerous medications, dietary supplements, and behavioral treatments have been recommended for the management of this condition, however, there is no cure yet. Recent studies have examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitors in neurodevelopmental diseases, based on their proved anti-inflammatory effects, such as downregulating the expression of several proteins, including the transforming growth factor beta (TGF-β), interleukin-6 (IL-6), C-reactive protein (CRP), nuclear factor κB (NF-κB), tumor necrosis factor alpha (TNF-α), and the monocyte chemoattractant protein (MCP-1). Furthermore, numerous previous studies revealed the potential of the SGLT2 inhibitors to provide antioxidant effects, due to their ability to reduce the generation of free radicals and upregulating the antioxidant systems, such as glutathione (GSH) and superoxide dismutase (SOD), while crossing the blood brain barrier (BBB). These properties have led to significant improvements in the neurologic outcomes of multiple experimental disease models, including cerebral oxidative stress in diabetes mellitus and ischemic stroke, Alzheimer's disease (AD), Parkinson's disease (PD), and epilepsy. Such diseases have mutual biomarkers with ASD, which potentially could be a link to fill the gap of the literature studying the potential of repurposing the SGLT2 inhibitors' use in ameliorating the symptoms of ASD. This review will look at the impact of the SGLT2 inhibitors on neurodevelopmental disorders on the various models, including humans, rats, and mice, with a focus on the SGLT2 inhibitor canagliflozin. Furthermore, this review will discuss how SGLT2 inhibitors regulate the ASD biomarkers, based on the clinical evidence supporting their functions as antioxidant and anti-inflammatory agents capable of crossing the blood-brain barrier (BBB).

Empagliflozin Is Not Renoprotective in Non-Diabetic Rat Models of Chronic Kidney Disease

Gliflozins (sodium-glucose transporter-2 inhibitors) exhibited renoprotective effects not only in diabetic but also in non-diabetic patients with chronic kidney disease (CKD). Controversial results were reported in experimental non-diabetic models of CKD. Therefore, we examined empagliflozin effects in three CKD models, namely, in fawn-hooded hypertensive (FHH) rats, uninephrectomized salt-loaded (UNX + HS) rats, and in rats with Goldblatt hypertension (two-kidney, one-clip 2K1C) that were either untreated or treated with empagliflozin (10 mg/kg/day) for eight weeks. Plethysmography blood pressure (BP) was recorded weekly, and renal parameters (proteinuria, plasma urea, creatinine clearance, and sodium excretion) were analyzed three times during the experiment. At the end of the study, blood pressure was also measured directly. Markers of oxidative stress (TBARS) and inflammation (MCP-1) were analyzed in kidney and plasma, respectively. Body weight and visceral adiposity were reduced by empagliflozin in FHH rats, without a significant effect on BP. Experimentally induced CKD (UNX + HS and 2K1C) was associated with a substantial increase in BP and relative heart and kidney weights. Empagliflozin influenced neither visceral adiposity nor BP in these two models. Although empagliflozin increased sodium excretion, suggesting effective SGLT-2 inhibition, it did not affect diuresis in any experimental model. Unexpectedly, empagliflozin did not provide renoprotection because proteinuria, plasma urea, and plasma creatinine were not lowered by empagliflozin treatment in all three CKD models. In line with these results, empagliflozin treatment did not decrease TBARS or MCP-1 levels in either model. In conclusion, empagliflozin did not provide the expected beneficial effects on kidney function in experimental models of CKD.

Cardiovascular protection by SGLT2 inhibitors - Do anti-inflammatory mechanisms play a role?

BACKGROUND

Metabolic syndrome and related metabolic disturbances represent a state of low-grade inflammation, which accelerates insulin resistance, type 2 diabetes (T2D) and cardiovascular disease (CVD) progression. Among antidiabetic medications, sodium glucose co-transporter (SGLT) 2 inhibitors are the only agents which showed remarkable reductions in heart failure (HF) hospitalizations and major cardiovascular endpoints (MACE) as well as renal endpoints regardless of diabetes status in large randomized clinical outcome trials (RCTs). Although the exact mechanisms underlying these benefits are yet to be established, growing evidence suggests that modulating inflammation by SGLT2 inhibitors may play a key role.

SCOPE OF REVIEW

In this manuscript, we summarize the current knowledge on anti-inflammatory effects of SGLT2 inhibitors as one of the mechanisms potentially mediating their cardiovascular (CV) benefits. We introduce the different metabolic and systemic actions mediated by these agents which could mitigate inflammation, and further present the signalling pathways potentially responsible for their proposed direct anti-inflammatory effects. We also discuss controversies surrounding some of these mechanisms.

MAJOR CONCLUSIONS

SGLT2 inhibitors are promising anti-inflammatory agents by acting either indirectly via improving metabolism and reducing stress conditions or via direct modulation of inflammatory signalling pathways. These effects were achieved, to a great extent, in a glucose-independent manner which established their clinical use in HF patients with and without diabetes.

Meta-analysis of the effect of sodium-dependent glucose transporter 2 inhibitors on C-reactive protein in type 2 diabetes

BACKGROUND

As novel hypoglycemic drugs, the effects of sodium-dependent glucose transporter 2 inhibitors (SGLT-2I) on inflammatory factors such as C-reactive protein (CRP) remain unclear.

METHODS

We conducted a meta-analysis of studies on SGLT-2I in the treatment of type 2 diabetes (T2DM) to observe the changes of CRP in patients with T2DM. We searched 4 electronic databases (CNKI, PubMed, EMBASE, and Cochrane Library) for articles published up to December 31, 2021. Studies were analyzed using a random-effects model to obtain standard deviation mean differences (SMDs) and 95% confidence intervals (CIs). Sensitivity and subgroup analyses were performed. Publication bias was evaluated using funnel plots and Egger test.

RESULTS

We included data from 927 patients in 13 confirmatory trials that showed a significant decrease in CRP among patients with T2DM treated with SGLT-2I. The decrease was more significant with than without SGLT-2I. In subgroup analysis according to nationality, medication, and comorbidities, CRP reduction was associated with nationality, SGLT-2I type, and the presence of comorbidities. Sensitivity analysis showed that our results were reliable and found no evidence of substantial publication bias.

CONCLUSIONS

SGLT-2I could reduce CRP levels in patients with T2DM.

REGISTRATION

International Prospective Register for Systematic Reviews (PROSPERO) number CRD42021268079.

Reactive Oxygen Species Scavenging Nanomedicine for the Treatment of Ischemic Heart Disease

Ischemic heart disease (IHD) is the leading cause of disability and mortality worldwide. Reactive oxygen species (ROS) have been shown to play key roles in the progression of diabetes, hypertension, and hypercholesterolemia, which are independent risk factors that lead to atherosclerosis and the development of IHD. Engineered biomaterial-based nanomedicines are under extensive investigation and exploration, serving as smart and multifunctional nanocarriers for synergistic therapeutic effect. Capitalizing on cell/molecule-targeting drug delivery, nanomedicines present enhanced specificity and safety with favorable pharmacokinetics and pharmacodynamics. Herein, the roles of ROS in both IHD and its risk factors are discussed, highlighting cardiovascular medications that have antioxidant properties, and summarizing the advantages, properties, and recent achievements of nanomedicines that have ROS scavenging capacity for the treatment of diabetes, hypertension, hypercholesterolemia, atherosclerosis, ischemia/reperfusion, and myocardial infarction. Finally, the current challenges of nanomedicines for ROS-scavenging treatment of IHD and possible future directions are discussed from a clinical perspective.

Correlation between albuminuria and interstitial injury marker reductions associated with SGLT2 inhibitor treatment in diabetic patients with renal dysfunction

Background

We investigated the effects of sodium–glucose cotransporter 2 inhibitor (SGLT2i) administration focusing on its involvement in tubulo-interstitial disorders in diabetic kidney.

Methods

Enrolled patients with diabetic kidney disease received a mean dose of 52.3 mg of an SGLT2i (ipragliflozin) daily. Blood and urine were sampled at 0, 1, and 12 months (M).

Results

Non-renal-dysfunction patients (NRD: baseline eGFR ≥ 60 mL/min/1.73 m², n = 12) and renal-dysfunction patients (RD: baseline eGFR < 60 mL/min/1.73 m², n = 9) were analyzed separately. The median urine albumin-to-Cr ratio (ACR) was significantly decreased at 1 M in both groups (NRD: 163.1 at 0 M vs 118.5 mg/g Cr at 1 M, RD: 325.2 at 0 M vs 136.0 mg/g Cr at 1 M). In the RD, but not the NRD group, reduction of urine monocyte chemotactic protein-1 (MCP-1) by SGLT2i showed a significant difference between high-responders (HR: − 25.7 ± 11.4%) and low-responders (LR: 59.2 ± 17.0%), defined by ACR reduction at 1 M. Univariate analysis showed a significant correlation between the reduction of ACR and MCP-1 (R = 0.683, p = 0.042) in RD.

Conclusion

SGLT2i exerted an anti-albuminuric effect regardless of the presence/absence of renal dysfunction. However, the anti-albuminuric effect of SGLT2i in patients with renal dysfunction appears more closely associated with amelioration of tubulo-interstitial disorders compared to patients without renal dysfunction.

The action of curcumin against damage resulting from cerebral stroke: a systematic review

Stroke is the second leading cause of morbidity and mortality globally. Treatments for stroke are limited, and preventive treatments are scarce. Curcumin (CUR) has several biological effects, as described in the literature, which highlight its antioxidant and neuroprotective effects. Therefore, this qualitative systematic review aimed to investigate the effects of CUR on damage caused by stroke in rodent models. A systematic search was performed on three databases PubMed, Scopus, and Web of Science. In addition, the risk-of-bias and quality of the studies were assessed using SYRCLE and Collaborative Approach for Meta-Analysis and Review of Animal Data from Experimental Studies, respectively. The selection, inclusion, and exclusion criteria were established by the authors. At the end of our systematic search of the three databases, we found a total of 728 articles. After excluding duplicates and triplicates and reading the abstracts, keywords, and full texts, 53 articles were finally included in this systematic review. CUR exerts several beneficial effects against the damage caused by both ischemic and hemorrhagic stroke, via different pathways. However, because of its low bioavailability, Free-form CUR only exerted significant effects when it was administered at high concentrations. In contrast, when CUR was administered using nanostructured systems, positive responses were observed even at low concentrations. The mechanisms of action of CUR, free or in nanostructure, are extremely important for the recovery of injured brain tissue after a stroke; CUR has neuroprotective, antioxidant, anti-inflammatory, and anti-apoptotic effects and helps to maintain the integrity of the blood-brain barrier. Finally, we concluded that CUR presents an extremely important and significant response profile against the damage caused by stroke, making it a possible therapeutic candidate for individuals affected by this disease.

Effect of sodium-glucose cotransporter-2 inhibitors on blood pressure in patients with heart failure: a systematic review and meta-analysis

Background

Recent studies have shown that sodium-glucose cotransporter-2 inhibitors (SGLT2i) can achieve significant improvement in blood pressure in people with diabetes. Furthermore, randomized controlled trials (RCTs) have established that SGLT2i have a cardioprotective effect in adults with heart failure (HF). Therefore, we performed this systematic review an meta-analysis to determine the effect of SGLT2i on blood pressure in patients with HF.

Methods

We used the Medline, Cochrane Library, Embase, and PubMed databases to identify RCTs (published through to April 29, 2022) that evaluated the effect of SGLT2i on HF. The primary endpoint was defined as change in blood pressure. Secondary composite outcomes were heart rate, hematocrit, body weight, and glycated hemoglobin. The N-terminal pro-brain natriuretic peptide level, Kansas City Cardiomyopathy Questionnaire scores, and estimated glomerular filtration rate were also evaluated.

Results

After a literature search and detailed evaluation, 16 RCTs were included in the quantitative analysis. Pooled analyses showed that SGLT2i were associated with a statistically significant reduction in systolic blood pressure of 1.68 mmHg (95% confidence interval [CI] − 2.7, − 0.66; P = 0.001; I² = 45%) but not diastolic blood pressure (mean difference [MD] −1.06 mmHg; 95% CI −3.20, 1.08; P = 0.33; I² = 43%) in comparison with controls. Furthermore, SGLT2i decreased body weight (MD − 1.36 kg, 95% CI − 1.68, − 1.03; P < 0.001; I² = 61%) and the glycated hemoglobin level (MD − 0.16%, 95% CI − 0.28, −0.04, P = 0.007; I² = 91%) but increased hematocrit (MD 1.63%, 95% CI 0.63, 2.62, P = 0.001; I² = 100%). There was no significant between-group difference in heart rate (MD − 0.35; 95% CI − 2.05, 1.35, P = 0.69; I² = 0).

Conclusions

SGLT2i decreased systolic blood pressure in patients with HF but had no effect on diastolic blood pressure. These inhibitors may have numerous potentially beneficial clinical effects in patients with HF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01574-w.

Kidney Angiotensin in Cardiovascular Disease: Formation and Drug Targeting

The concept of local formation of angiotensin II in the kidney has changed over the last 10-15 years. Local synthesis of angiotensinogen in the proximal tubule has been proposed, combined with prorenin synthesis in the collecting duct. Binding of prorenin via the so-called (pro)renin receptor has been introduced, as well as megalin-mediated uptake of filtered plasma-derived renin-angiotensin system (RAS) components. Moreover, angiotensin metabolites other than angiotensin II [notably angiotensin-(1-7)] exist, and angiotensins exert their effects via three different receptors, of which angiotensin II type 2 and Mas receptors are considered renoprotective, possibly in a sex-specific manner, whereas angiotensin II type 1 (AT1) receptors are believed to be deleterious. Additionally, internalized angiotensin II may stimulate intracellular receptors. Angiotensin-converting enzyme 2 (ACE2) not only generates angiotensin-(1-7) but also acts as coronavirus receptor. Multiple, if not all, cardiovascular diseases involve the kidney RAS, with renal AT1 receptors often being claimed to exert a crucial role. Urinary RAS component levels, depending on filtration, reabsorption, and local release, are believed to reflect renal RAS activity. Finally, both existing drugs (RAS inhibitors, cyclooxygenase inhibitors) and novel drugs (angiotensin receptor/neprilysin inhibitors, sodium-glucose cotransporter-2 inhibitors, soluble ACE2) affect renal angiotensin formation, thereby displaying cardiovascular efficacy. Particular in the case of the latter three, an important question is to what degree they induce renoprotection (e.g., in a renal RAS-dependent manner). This review provides a unifying view, explaining not only how kidney angiotensin formation occurs and how it is affected by drugs but also why drugs are renoprotective when altering the renal RAS. SIGNIFICANCE STATEMENT: Angiotensin formation in the kidney is widely accepted but little understood, and multiple, often contrasting concepts have been put forward over the last two decades. This paper offers a unifying view, simultaneously explaining how existing and novel drugs exert renoprotection by interfering with kidney angiotensin formation.

Modulation of Reactive Oxygen Species Homeostasis as a Pleiotropic Effect of Commonly Used Drugs

Age-associated diseases represent a growing burden for global health systems in our aging society. Consequently, we urgently need innovative strategies to counteract these pathological disturbances. Overwhelming generation of reactive oxygen species (ROS) is associated with age-related damage, leading to cellular dysfunction and, ultimately, diseases. However, low-dose ROS act as crucial signaling molecules and inducers of a vaccination-like response to boost antioxidant defense mechanisms, known as mitohormesis. Consequently, modulation of ROS homeostasis by nutrition, exercise, or pharmacological interventions is critical in aging. Numerous nutrients and approved drugs exhibit pleiotropic effects on ROS homeostasis. In the current review, we provide an overview of drugs affecting ROS generation and ROS detoxification and evaluate the potential of these effects to counteract the development and progression of age-related diseases. In case of inflammation-related dysfunctions, cardiovascular- and neurodegenerative diseases, it might be essential to strengthen antioxidant defense mechanisms in advance by low ROS level rises to boost the individual ROS defense mechanisms. In contrast, induction of overwhelming ROS production might be helpful to fight pathogens and kill cancer cells. While we outline the potential of ROS manipulation to counteract age-related dysfunction and diseases, we also raise the question about the proper intervention time and dosage.

SGLT2 inhibition effect on salt-induced hypertension, RAAS, and Na+ transport in Dahl SS rats

Na+-glucose cotransporter-2 (SGLT2) inhibitors are the new mainstay of treatment for diabetes mellitus and cardiovascular diseases. Despite the remarkable benefits, the molecular mechanisms mediating the effects of SGLT2 inhibitors on water and electrolyte balance are incompletely understood. The goal of this study was to determine whether SGLT2 inhibition alters blood pressure and kidney function via affecting the renin-angiotensin-aldosterone system (RAAS) and Na+ channels/transporters along the nephron in Dahl salt-sensitive rats, a model of salt-induced hypertension. Administration of dapagliflozin (Dapa) at 2 mg/kg/day via drinking water for 3 wk blunted the development of salt-induced hypertension as evidenced by lower blood pressure and a left shift of the pressure natriuresis curve. Urinary flow rate, glucose excretion, and Na+- and Cl--to-creatinine ratios increased in Dapa-treated compared with vehicle-treated rats. To define the contribution of the RAAS, we measured various hormones. Despite apparent effects on Na+- and Cl--to-creatinine ratios, Dapa treatment did not affect RAAS metabolites. Subsequently, we assessed the effects of Dapa on renal Na+ channels and transporters using RT-PCR, Western blot analysis, and patch clamp. Neither mRNA nor protein expression levels of renal transporters (SGLT2, Na+/H+ exchanger isoform 3, Na+-K+-2Cl- cotransporter 2, Na+-Cl- cotransporter, and α-, β-, and γ-epithelial Na+ channel subunits) changed significantly between groups. Furthermore, electrophysiological experiments did not reveal any difference in Dapa treatment on the conductance and activity of epithelial Na+ channels. Our data suggest that SGLT2 inhibition in a nondiabetic model of salt-sensitive hypertension blunts the development of salt-induced hypertension by causing glucosuria and natriuresis without changes in the RAAS or the expression or activity of the main Na+ channels and transporters.NEW & NOTEWORTHY The present study indicates that Na+-glucose cotransporter-2 (SGLT2) inhibition in a nondiabetic model of salt-sensitive hypertension blunts the development and magnitude of salt-induced hypertension. Chronic inhibition of SGLT2 increases glucose and Na+ excretion without secondary effects on the expression and function of other Na+ transporters and channels along the nephron and hormone levels in the renin-angiotensin-aldosterone system. These data provide novel insights into the effects of SGLT2 inhibitors and their potential use in hypertension.

Role of Sodium-Glucose Co-Transporter 2 Inhibitors in the Regulation of Inflammatory Processes in Animal Models

Sodium-glucose co-transporter 2 inhibitors, also known as gliflozins, were developed as a novel class of anti-diabetic agents that promote glycosuria through the prevention of glucose reabsorption in the proximal tubule by sodium-glucose co-transporter 2. Beyond the regulation of glucose homeostasis, they resulted as being effective in different clinical trials in patients with heart failure, showing a strong cardio-renal protective effect in diabetic, but also in non-diabetic patients, which highlights the possible existence of other mechanisms through which gliflozins could be exerting their action. So far, different gliflozins have been approved for their therapeutic use in T2DM, heart failure, and diabetic kidney disease in different countries, all of them being diseases that have in common a deregulation of the inflammatory process associated with the pathology, which perpetuates and worsens the disease. This inflammatory deregulation has been observed in many other diseases, which led the scientific community to have a growing interest in the understanding of the biological processes that lead to or control inflammation deregulation in order to be able to identify potential therapeutic targets that could revert this situation and contribute to the amelioration of the disease. In this line, recent studies showed that gliflozins also act as an anti-inflammatory drug, and have been proposed as a useful strategy to treat other diseases linked to inflammation in addition to cardio-renal diseases, such as diabetes, obesity, atherosclerosis, or non-alcoholic fatty liver disease. In this work, we will review recent studies regarding the role of the main sodium-glucose co-transporter 2 inhibitors in the control of inflammation.

Characteristics and molecular mechanisms through which SGLT2 inhibitors improve metabolic diseases: A mechanism review

Metabolic diseases, such as diabetes, gout and hyperlipidemia are global health challenges. Among them, diabetes has been extensively investigated. Type 2 diabetes mellitus (T2DM), which is characterized by hyperglycemia, is a complex metabolic disease that is associated with various metabolic disorders. The newly developed oral hypoglycemic agent, sodium-glucose cotransporter 2 (SGLT2) inhibitor, has been associated with glucose-lowering effects and it affects metabolism in various ways. However, the potential mechanisms of SGLT2 inhibitors in metabolic diseases have not fully reviewed. Many of the effects beyond glycemic control must be considered off-target effects. Therefore, we reviewed the effects of SGLT2 inhibition on metabolic diseases such as obesity, hypertension, hyperlipidemia, hyperuricemia, fatty liver disease, insulin resistance, osteoporosis and fractures. Moreover, we elucidated their molecular mechanisms to provide a theoretical basis for metabolic disease treatment.

Effect of Empagliflozin on Sphingolipid Catabolism in Diabetic and Hypertensive Rats

The profile of sphingomyelin and its metabolites shows changes in the plasma, organs, and tissues of patients with cardiovascular, renal, and metabolic diseases. The objective of this study was to investigate the effect of empagliflozin on the levels of sphingomyelin and its metabolites, as well as on the activity of acid and neutral sphingomyelinase (aSMase and nSMase) and neutral ceramidase (nCDase) in the plasma, kidney, heart, and liver of streptozotocin-induced diabetic and Angiotensin II (Ang II)-induced hypertension rats. Empagliflozin treatment decreased hyperglycemia in diabetic rats whereas blood pressure remained elevated in hypertensive rats. In diabetic rats, empagliflozin treatment decreased sphingomyelin in the plasma and liver, ceramide in the heart, sphingosine-1-phosphate (S1P) in the kidney, and nCDase activity in the plasma, heart, and liver. In hypertensive rats, empagliflozin treatment decreased sphingomyelin in the plasma, kidney, and liver; S1P in the plasma and kidney; aSMase in the heart, and nCDase activity in the plasma, kidney, and heart. Our results suggest that empagliflozin downregulates the interaction of the de novo pathway and the catabolic pathway of sphingolipid metabolism in the diabetes, whereas in Ang II-dependent hypertension, it only downregulates the sphingolipid catabolic pathway.

Targeting Features of the Metabolic Syndrome Through Sympatholytic Effects of SGLT2 Inhibition

PURPOSE OF REVIEW

The moderate glucose-lowering effect of sodium glucose co-transporter 2 (SGLT2) inhibitors is unlikely to explain SGLT2 inhibitor-mediated beneficial outcomes, and unravelling the underlying mechanisms is a high priority in the research community. Given the dominant pathophysiologic role of the sympathetic nervous system activation in conditions such as hypertension and perturbed glucose homeostasis, it is pertinent to postulate that SGLT2 inhibitors may exert their beneficial effects at least in part via sympathetic inhibition.

RECENT FINDINGS

SGLT2 inhibitors have shown enormous potential to improve cardiovascular outcomes in patients with type 2 diabetes, and their therapeutic potential is currently being investigated in a range of associated comorbidities such as heart failure and chronic kidney disease. Indeed, recent experimental data in relevant animal models highlight a bidirectional interaction between sympathetic nervous system activation and SGLT2 expression, and this facilitates several of the features associated with SGLT2 inhibition observed in clinical trials including improved glucose metabolism, weight loss, increased diuresis, and lowering of blood pressure. Currently available data highlight the various levels of interaction between the sympathetic nervous system and SGLT2 expression and explores the potential for SGLT2 inhibition as a therapeutic strategy in conditions commonly characterised by sympathetic activation.

MicroRNAs and their delivery in diabetic fibrosis

The global prevalence of diabetes mellitus was estimated to be 463 million people in 2019 and is predicted to rise to 700 million by 2045. The associated financial and societal costs of this burgeoning epidemic demand an understanding of the pathology of this disease, and its complications, that will inform treatment to enable improved patient outcomes. Nearly two decades after the sequencing of the human genome, the significance of noncoding RNA expression is still being assessed. The family of functional noncoding RNAs known as microRNAs regulates the expression of most genes encoded by the human genome. Altered microRNA expression profiles have been observed both in diabetes and in diabetic complications. These transcripts therefore have significant potential and novelty as targets for therapy, therapeutic agents and biomarkers.

Can sodium-glucose co-transporter-2 (SGLT-2) inhibitor reduce the risk of adverse complications due to COVID-19? - Targeting hyperinflammation

Sodium-glucose co-transporter-2 (SGLT-2) inhibitors are antidiabetic drugs with numerous pleiotropic and positive clinical effects, particularly regarding a reno-cardiovascular protective effect. More recent studies, including from our laboratory, have highlighted some novel anti-inflammatory activity of SGLT-2 inhibitors. This may confer a theoretical advantage in mitigating excessive cytokine production and inflammatory response associated with serious COVID-19 infection. Specifically, earlier research has demonstrated that SGLT-2 inhibitors are associated with a notable decrease in inflammatory indicators, for example, C-reactive protein, ferritin, and interleukin-6. Furthermore, SGLT-2 inhibitors exhibit a favourable impact on the vascular endothelium function; this could pertinence the prophylaxis of the thrombotic issues that arise in SARS-CoV-2. This review provides an overview of the COVID-19 indirect immune response mechanisms impacting the cardiovascular system and the possible effect of SGLT-2 inhibitors on the management of COVID-19.

Antioxidant Roles of SGLT2 Inhibitors in the Kidney

The reduction-oxidation (redox) system consists of the coupling and coordination of various electron gradients that are generated thanks to serial reduction-oxidation enzymatic reactions. These reactions happen in every cell and produce radical oxidants that can be mainly classified into reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS modulate cell-signaling pathways and cellular processes fundamental to normal cell function. However, overproduction of oxidative species can lead to oxidative stress (OS) that is pathological. Oxidative stress is a main contributor to diabetic kidney disease (DKD) onset. In the kidney, the proximal tubular cells require a high energy supply to reabsorb proteins, metabolites, ions, and water. In a diabetic milieu, glucose-induced toxicity promotes oxidative stress and mitochondrial dysfunction, impairing tubular function. Increased glucose level in urine and ROS enhance the activity of sodium/glucose co-transporter type 2 (SGLT2), which in turn exacerbates OS. SGLT2 inhibitors have demonstrated clear cardiovascular benefits in DKD which may be in part ascribed to the generation of a beneficial equilibrium between oxidant and antioxidant mechanisms.

Extending the ambit of SGLT2 inhibitors beyond diabetes: a review of clinical and preclinical studies on non-diabetic kidney disease

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are novel antidiabetic agents with overwhelming cardiorenal protection. Recent trials focusing on the nephroprotective role of SGLT2i have underscored its success as a phenomenal agent in halting the progression of kidney disease in patients with and without Type 2 diabetes mellitus. Multitudes of pleiotropic effects on tubules have raised hopes for reasonable nephroprotection beyond the purview of the hyperglycemic milieu.

AREA COVERED

This review summarizes various animal and human data as evidence for the utility of SGLT2i in non-diabetic chronic kidney disease (CKD). Web-based medical database entries were searched. On the premise of existing evidence, we have discussed mechanisms likely contributing to nephroprotection by SGLT2i in patients with non-diabetic CKD.

EXPERT OPINION

Further elucidation of mechanisms of nephroprotection offered by SGLT2i is required to extend its use as a nephroprotective agent. The use of non-traditional markers of kidney damage in future studies would improve the evaluation of their role in attenuating CKD progression. Emerging animal data support the early use of SGLT2i in states of modest proteinuria for superior outcomes. Future long-term trials in patients should aim to address the time of intervention with SGLT2i during the natural disease course of CKD for best outcomes.

Dapagliflozin Guards Against Cadmium-Induced Cardiotoxicity via Modulation of IL6/STAT3 and TLR2/TNFα Signaling Pathways

Cadmium (Cd) is a common environmental pollutant that leads to severe cardiotoxic hazards. Several studies were carried out to protect the myocardium against Cd-induced cardiotoxicity. Up till now, no researches evaluated the protective effect of dapagliflozin (DAP) against Cd induced cardiotoxicity. Thus, we aimed to explore the role of DAP in such model with deep studying of the involved mechanisms. 40 male Wistar albino rats were included in current study. Cd (5 mg/kg/day) was administered orally for 7 days to induce cardiotoxicity with or without co-administration of DAP in three different doses (2.5, 5, 10 mg/kg/day) orally for 7 days. Our data revealed that Cd could induce cardiotoxicity with significant increase in serum cardiac enzymes, heart weight, tissue malondialdehyde (MDA), tumor necrosis factor alpha (TNFα), nuclear factor kappa B (NFκB), toll like receptor2 (TLR2), interleukin 6 (IL6) and caspase3 immunoexpression with abnormal histopathological changes. In addition, Cd significantly decreased the level of heme oxygenase1 (HO1), nuclear factor erythroid 2-related factor 2 (Nrf2), signal transducer and activator of transcription (STAT3), reduced glutathione (GSH), glutathione peroxidase (GPx), and total antioxidant capacity (TAC). Co-administration of DAP could ameliorate Cd cardiotoxicity with significant improvement of the biochemical and histopathological changes. We found that DAP had protective properties against Cd induced cardiotoxicity and this may be due to its anti-oxidant, anti-inflammatory, anti-apoptotic properties and modulation of IL6/STAT3 and TLR2/TNFα-signaling pathways.