Unleashing the pathological role of epithelial-to-mesenchymal transition in diabetic nephropathy: The intricate connection with multifaceted mechanism.

Renal epithelial-to-mesenchymal transition (EMT) is a process in which epithelial cells undergo biochemical changes and transform into mesenchymal-like cells, resulting in renal abnormalities, including fibrosis. EMT can cause diabetic nephropathy through triggering kidney fibrosis, inflammation, and functional impairment. The diverse molecular pathways that drive EMT-mediated renal fibrosis are not utterly known. Targeting key signaling pathways involved in EMT may help ameliorate diabetic nephropathy and improve renal function. In such settings, understanding precisely the complicated signaling networks is critical for developing customized therapies to intervene in EMT-mediated diabetic nephropathy.

The art and science of research methodology, biostatistics, manuscript writing, and publication ethics: An invigorating training for improving research aptitudes in southern Indian biomedical institutions.

The basic concepts of research are learned through systematic literature searches which form the basis of a research statement and research topic. Then the research question, hypothesis, aim, and objectives, as well as the experimental design, are developed. Given the context provided, the primary focus is on the importance of adequately training postgraduates and young research investigators in research methodology and project development. It is evident that there is a lack of proper training in these areas, and the rapid expansion of colleges in India exacerbates this issue. To address this, research students must receive comprehensive instruction in scientific research methodology, experimental design, statistics, scientific writing, publishing, and research ethics. Our team has been conducting workshops and symposia for more than two decades to improve the current teaching methods in these areas. Most recently, we organized a series of national and international workshops and seminars in multiple states across India to fortify the core concepts of scientific research for students and faculty members. This report highlights the key aspects of these workshops and the positive outcomes experienced by participants.

Mechanistic insights into the beneficial effects of curcumin on insulin resistance: Opportunities and challenges.

The past couple of decades in particular have seen a rapid increase in the prevalence of type 2 diabetes mellitus (T2DM), a debilitating metabolic disorder characterised by insulin resistance. The insufficient efficacy of current management strategies for insulin resistance calls for additional therapeutic options. The preponderance of evidence suggests potential beneficial effects of curcumin on insulin resistance, while modern science provides a scientific basis for its potential applications against the disease. Curcumin combats insulin resistance by increasing the levels of circulating irisin and adiponectin, activating PPARγ, suppressing Notch1 signalling, and regulating SREBP target genes, among others. In this review, we bring together the diverse areas pertaining to our current understanding of the potential benefits of curcumin on insulin resistance, associated mechanistic insights, and new therapeutic possibilities.

A Unifying Perspective in Blunting the Limited Oral Bioavailability of Curcumin: A Succinct Look.

BACKGROUND: Curcumin is a polyphenolic compound derived from rhizomes of Curcuma longa, the golden spice. Curcumin has drawn much attention in recent years of biomedical research owing to its wide variety of biologic and pharmacologic actions. It exerts antiproliferative, antifibrogenic, anti-inflammatory, and antioxidative effects, among various imperative pharmacologic actions. In spite of its well-documented efficacies against numerous disease conditions, the limited systemic bioavailability of curcumin is a continuing concern. Perhaps, the poor bioavailability of curcumin may have curtailed its significant development from kitchen to clinic as a potential therapeutic agent. Subsequently, there have been a considerable number of studies over decades researching the scientific basis of curcumin's reduced bioavailability and eventually improvement of its bioavailability employing a variety of therapeutic approaches, for instance, in combination with piperine, the bio-active constituent of black pepper. Piperine has remarkable potential to modulate the functional activity of metabolic enzymes and drug transporters, and thus there has been a great interest in the therapeutic application of this widely used spice as alternative medicine and bioavailability enhancer. Growing body of evidence supports the synergistic potential of curcumin against numerous pathologic conditions when administered with piperine. CONCLUSION: In light of current challenges, the major concern pertaining to poor systemic bioavailability of curcumin, its improvement, especially in combination with piperine, and the necessity of additional research in this setting are together described in this review. Besides, the recent advances in the potential therapeutic rationale and efficacy of curcumin-piperine combination, a promising duo, against various pathologic conditions are delineated.

Unraveling the Differentially Articulated Axes of the Century-Old Renin-Angiotensin-Aldosterone System: Potential Therapeutic Implications.

Among numerous choices in cardiovascular therapies used for the management of hypertension and heart failure, drugs affecting the renin-angiotensin-aldosterone system (RAAS) hold substantial therapeutic roles. Therapies aimed at modifying the RAAS and its overactivation are employed for the management of various insidious disorders. In the pharmacologic perspective, RAAS is one of the frequently manipulated systems for the management of hypertension, heart failure, myocardial infarction, and renal disease. The RAAS pharmacologic interventions principally include the ACE inhibitors, the angiotensin II-AT1 receptor blockers, the mineralocorticoid receptor antagonists, and the direct renin inhibitors. In addition, therapeutic implication of ACE2/angiotensin (1-7)/Mas receptor activation using various ligands is being explored owing to their anti-inflammatory, anti-fibrotic, vasodilatory, and cardiovascular defensive roles. Moreover, being considered as the counter-regulatory arm of AT1 receptor, the potential role of AT2 receptor activation using selective AT2 receptor agonist is currently investigated for its efficacy in pulmonary complications. As an important regulator of fluid volume, blood pressure, and cardiovascular-renal function, the RAAS has been documented as a diversified intricate system with several therapeutic possibilities coupled with their fundamental structural and functional modulatory roles in cardiovascular, renal, and other systems. The RAAS possesses a number of regulatory, deregulatory, and counter-regulatory axes of physiopathologic importance in health and disease. The counter-regulatory arms of the RAAS might play an essential role in mitigating cardiovascular, renal, and pulmonary pathologies. In light of this background, we sought to explore the classical and counter-regulatory axes/arms of the RAAS and their imperative roles in physiologic functions and disease pathogenesis.

Dysregulation of the renin-angiotensin system in septic shock: Mechanistic insights and application of angiotensin II in clinical management.

Synergistic physiologic mechanisms involving the renin-angiotensin system (RAS), the sympathetic nervous system, and the arginine-vasopressin system play an integral role in blood pressure homeostasis. A subset of patients with sepsis experience septic shock with attendant circulatory, cellular, and metabolic abnormalities. Septic shock is associated with increased mortality because of an inadequacy to maintain mean arterial blood pressure (MAP) despite volume resuscitation and the use of vasopressors. Vasodilatory shock raises the dose of vasopressors required to maintain a MAP of > 65 mm Hg. The diminished response to endogenous angiotensin II in sepsis-induced vasoplegia may be related to the aberrant RAS activation that stimulates a proinflammatory beneficial antibacterial response, increasing the secretion of proinflammatory cytokines that downregulate AT-1 receptors expression. Moreover, excessive systemic upregulation of nitric oxide synthase, stimulation of prostaglandin synthesis, and activation of ATP-sensitive potassium channels followed by reduced vascular entry of calcium ions are putative mechanisms in the reduced responsiveness to vasopressors. However, intravenous angiotensin II in catecholamine-resistant septic shock patients showed substantial evidence of raising the MAP to target hemodynamic levels, thus allowing time to treat underlying conditions. Nevertheless, evidence of catecholamine-sparing effect by adding angiotensin II, aimed at increasing the therapeutic index of vasopressor therapy, does not show an attenuation of end-organ damage. The use of angiotensin II in septic shock has not been evaluated in patients who are not catecholamine resistant. This, in conjunction with an evolving definition of catecholamine resistance, provides an opportunity for further evaluation of exogenous angiotensin II in septic shock.

The physiologic and physiopathologic roles of perivascular adipose tissue and its interactions with blood vessels and the renin-angiotensin system.

The perivascular adipose tissue (PVAT) refers to an ectopic local deposit of connective tissue that anatomically surrounds most of the blood vessels. While it was initially known only as a structural support for vasculature, the landmark findings of Soltis and Cassis (1991), first demonstrating that PVAT reduces the contractions of norepinephrine in the isolated rat aorta, brought the potential vascular role of PVAT into the limelight. This seminal work implied the potential ability of PVAT to influence vascular responsiveness. Several vasoactive/vasocrine substances influencing vascular homeostasis were successively shown to be released from PVAT that include both adipocyte-derived relaxing and contracting factors. The PVAT is currently recognized as a metabolically active endocrine organ and is eventually considered as the 'protagonist' in vascular homeostasis. It plays prominent defending and opposing roles in vascular function, while the actual vascular influences of PVAT vary with an increase in adiposity. Recent studies have presented compelling evidence implicating the pivotal role of PVAT in the local activation of the renin-angiotensin system (RAS), which substantially impacts vascular physiology and physiopathology. Current findings have advanced our understanding of the role of PVAT in favorably or adversely modulating the vascular function through differential RAS activation. Given that adipocytes also produce major RAS components locally to influence vascular function, this review provides a scientific basis to distinctly understand the key role of PVAT in regulating the autocrine and paracrine functions of vascular RAS components and its potential as an emerging therapeutic target for mitigating cardiovascular complications.

Mechanistic insights into hyperuricemia-associated renal abnormalities with special emphasis on epithelial-to-mesenchymal transition: Pathologic implications and putative pharmacologic targets.

Though the pathogenesis of hyperuricemia-induced renal complications is not precisely known, hyperuricemia has been recognized as an independent risk factor for renal disease. While the clinical implication of hyperuricemia in renal disease has been a contemporary topic of debate, growing body of bench and clinical evidences certainly suggest a causative role of high uric acid in renal abnormalities by implicating diverse pathologic and molecular mechanisms. Urate crystals after having deposited in the kidney could cause hyperuricemia nephropathy leading to glomerular hypertrophy and tubulointerstitial fibrosis, while high serum uric acid might predict progressive renal damage and dysfunction. Hyperuricemia could be associated with manifestation of tubular injury and macrophage infiltration as well as an increased expression of inflammatory mediators. This review sheds light on the mechanistic aspects pertaining to hyperuricemia-associated renal abnormalities. Besides, the renal detrimental actions of high uric acid possibly mediated through its potential role on oxidative stress, renal inflammation, endothelial dysfunction, glycocalyx shedding, endothelial-to-mesenchymal transition and more specifically on the renal epithelial-to-mesenchymal transition have been addressed. Moreover, this review discusses a number of potential targets such as endothelin-1, TLR4/NF-kB, PI3K/p-Akt, Wnt5a/Ror2, NLRP3 inflammasome, NADPH oxidase, ERK1/2, enhancer of zeste homolog 2, serum response factor and Smad3/TGF-ß signalling pathways, among others, implicated in hyperuricemia-associated renal abnormalities. This review finally apprises a number of bench and clinical studies which supporting a notion that the pharmacologic reduction of high uric acid might have a therapeutic value in the management of renal abnormalities, with an emphasis on febuxostat and its renal pleiotropic actions.

A potential role of the renin-angiotensin-aldosterone system in epithelial-to-mesenchymal transition-induced renal abnormalities: Mechanisms and therapeutic implications.

Epithelial-to-mesenchymal transition (EMT) is an orchestrated event where epithelial cells progressively undergo biochemical changes and transition into mesenchymal-like cells by gradually losing their epithelial characteristics. EMT plays a crucial pathologic role in renal abnormalities, especially renal fibrosis. A number of bench studies suggest the potential involvement of renin-angiotensin-aldosterone system (RAAS) in renal EMT process and associated renal abnormalities. EMT appears to be an important pathologic mechanism for the deleterious renal effects of angiotensin II and aldosterone, the two major RAAS components. Mechanistically, the renal RAAS-TGF-ß-Smad3 signalling pathway plays an important pathologic role in EMT-associated renal abnormalities. Intriguingly, the RAAS antagonists such as losartan, telmisartan, eplerenone, and spironolactone have the potential to prevent renal EMT in bench studies. This review describes the key mechanistic role of RAAS overactivation in EMT-induced renal abnormalities. Moreover, drugs interrupting the RAAS at different levels in the cascade ameliorating the EMT-associated renal abnormalities are described.

Molecular targets of fenofibrate in the cardiovascular-renal axis: A unifying perspective of its pleiotropic benefits.

The activation of peroxisome proliferator-activated receptor α (PPARα) is a key pharmacological drug target for dyslipidemic management. Dyslipidemia is associated with abnormal serum lipid profiles viz. elevated total cholesterol, high triglyceride, elevated low-density lipoprotein cholesterol, and reduced high-density lipoprotein cholesterol levels. Fenofibrate, a third-generation fibric acid derivative, is an activator of PPARα indicated for the treatment of mixed dyslipidemia and hypertriglyceridemia in adults. Fenofibrate is considered an important lipid-lowering medication employed in patients afflicted with atherogenic dyslipidemia. Intriguingly, recent bench studies have demonstrated an array of cardiovascular and renal pleiotropic beneficial activities of fenofibrate, besides its foremost lipid-lowering action. The activation of PPARα by fenofibrate could negatively regulate the cardiomyocyte hypertrophy. In addition, fenofibrate has been suggested to have a protective effect against experimental ischemia/reperfusion injury in the myocardium in part via endoplasmic reticulum stress inhibition. Fenofibrate has also been shown to suppress arrhythmias in isolated rat hearts subjected to ischemic/reperfusion-induced cardiac injury. Moreover, in a rat model of metabolic syndrome and myocardial ischemia, fenofibrate therapy has been shown to restore antioxidant protection and improve myocardial insulin resistance. Furthermore, studies have highlighted the pleiotropic vascular endothelial protective and antihypertensive actions of fenofibrate. Interestingly, recent bench studies have demonstrated renoprotective actions of fenofibrate by implicating diverse mechanisms. This review sheds light on the current perspectives and molecular mechanistic aspects pertaining to the cardiovascular pleiotropic actions of fenofibrate. Additionally, the renal pleiotropic actions of fenofibrate by focusing its possible modulatory role on renal fibrosis, inflammation and renal epithelial-to-mesenchymal transition have been enlightened.

A Contemporary Overview of PPARα/γ Dual Agonists for the Management of Diabetic Dyslipidemia.

BACKGROUND: Diabetes mellitus and concomitant dyslipidemia, being referred to as 'diabetic dyslipidemia', are the foremost detrimental factors documented to play a pivotal role in cardiovascular illness. Diabetic dyslipidemia is associated with insulin resistance, high plasma triglyceride levels, low HDL-cholesterol concentration and elevated small dense LDL-cholesterol particles. Maintaining an optimal glucose and lipid levels in patients afflicted with diabetic dyslipidemia could be a major task that might require a well-planned diet-management system and regular physical activity, or otherwise an intake of combined antidiabetic and antihyperlipidemic medications. Synchronized treatment which efficiently controls insulin resistance-associated diabetes mellitus and co-existing dyslipidemia could indeed be a fascinating therapeutic option in the management of diabetic dyslipidemia. Peroxisome proliferator-activated receptors α/γ (PPARα/γ) dual agonists are such kind of drugs which possess therapeutic potentials to treat diabetic dyslipidemia. Nevertheless, PPARα/γ dual agonists like muraglitazar, naveglitazar, tesaglitazar, ragaglitazar and aleglitazar have been reported to have undesirable adverse effects, and their developments have been halted at various stages. On the other hand, a recently introduced PPARα/γ dual agonist, saroglitazar is an emerging therapeutic agent of glitazar class approved in India for the management of diabetic dyslipidemia, and its treatment has been reported to be generally safe and well tolerated. CONCLUSION: Some additional and new compounds, at initial and preclinical stages, have been recently reported to possess PPARα/γ dual agonistic potentials with considerable therapeutic efficacy and reduced adverse profile. This review sheds light on the current status of various PPARα/γ dual agonists for the management of diabetic dyslipidemia.

Effects of pre and post-treatments with dipyridamole in gentamicin-induced acute nephrotoxicity in the rat.

This study investigated the pretreatment and post-treatment effects of dipyridamole (20 mg/kg/day, p.o.) in gentamicin-induced acute nephrotoxicity in rats. Rats were administered gentamicin (100 mg/kg/day, i.p.) for 8 days. Gentamicin-administered rats exhibited renal structural and functional changes as assessed in terms of a significant increase in serum creatinine and urea and kidney weight to body weight ratio as compared to normal rats. Renal histopathological studies revealed a marked incidence of acute tubular necrosis in gentamicin-administered rats. These renal structural and functional abnormalities in gentamicin-administered rats were accompanied with elevated serum uric acid level, and renal inflammation as assessed in terms of decrease in interleukin-10 levels. Dipyridamole pretreatment in gentamicin-administered rats afforded a noticeable renoprotection by markedly preventing renal structural and functional abnormalities, renal inflammation and serum uric acid elevation. On the other hand, dipyridamole post-treatment did not significantly prevent uric acid elevation and renal inflammation, and resulted in comparatively less protection on renal function although it markedly reduced the incidence of tubular necrosis. In conclusion, uric acid elevation and renal inflammation could play key roles in gentamicin-nephrotoxicity. Dipyridamole pretreatment markedly prevented gentamicin-induced acute nephrotoxicity, while its post-treatment resulted in comparatively less renal functional protection.

Prevalence and prevention of cardiovascular disease and diabetes mellitus.

Noncommunicable diseases (NCDs) have become important causes of mortality on a global scale. According to the report of World Health Organization (WHO), NCDs killed 38 million people (out of 56 million deaths that occurred worldwide) during 2012. Cardiovascular diseases accounted for most NCD deaths (17.5 million NCD deaths), followed by cancers (8.2 million NCD deaths), respiratory diseases (4.0 million NCD deaths) and diabetes mellitus (1.5 million NCD deaths). Globally, the leading cause of death is cardiovascular diseases; their prevalence is incessantly progressing in both developed and developing nations. Diabetic patients with insulin resistance are even at a greater risk of cardiovascular disease. Obesity, high cholesterol, hypertriglyceridemia and elevated blood pressure are mainly considered as major risk factors for diabetic patients afflicted with cardiovascular disease. The present review sheds light on the global incidence of cardiovascular disease and diabetes mellitus. Additionally, measures to be taken to reduce the global encumbrance of cardiovascular disease and diabetes mellitus are highlighted.

Effect of edaravone in diabetes mellitus-induced nephropathy in rats.

Edaravone, a synthetic-free radical scavenger, has been reported to reduce ischemia-reperfusion-induced renal injury by improving tubular cell function, and lowering serum creatinine and renal vascular resistance. The present study investigated the effect of edaravone in diabetes mellitus-induced nephropathy in rats. A single administration of streptozotocin (STZ, 55 mg/kg, i.p.) was employed to induce diabetes mellitus in rats. The STZ-administered diabetic rats were allowed for 10 weeks to develop nephropathy. Mean body weight, lipid alteration, renal functional and histopathology were analysed. Diabetic rats developed nephropathy as evidenced by a significant increase in serum creatinine and urea, and marked renal histopathological abnormalities like glomerulosclerosis and tubular cell degeneration. The kidney weight to body weight ratio was increased. Moreover, diabetic rats showed lipid alteration as evidenced by a signifi cant increase in serum triglycerides and decrease in serum high-density lipoproteins. Edaravone (10 mg/kg, i.p., last 4-weeks) treatment markedly prevented the development of nephropathy in diabetic rats by reducing serum creatinine and urea and preventing renal structural abnormalities. In addition, its treatment, without significantly altering the elevated glucose level in diabetic rats, prevented diabetes mellitus-induced lipid alteration by reducing serum triglycerides and increasing serum high-density lipoproteins. Interestingly, the renoprotective effect of edaravone was comparable to that of lisinopril (5 mg/kg, p.o, 4 weeks, standard drug). Edaravone prevented renal structural and functional abnormalities and lipid alteration associated with experimental diabetes mellitus. Edaravone has a potential to prevent nephropathy without showing an anti-diabetic action, implicating its direct renoprotection in diabetic rats.

Chronic oral administration of low-dose combination of fenofibrate and rosuvastatin protects the rat heart against experimentally induced acute myocardial infarction.

Fenofibrate and rosuvastatin at low doses might have experimental pleiotropic benefits. This study investigated the combined effect of low doses of fenofibrate and rosuvastatin in isoproterenol-induced experimental myocardial infarction. Rats administered isoproterenol (85 mg/kg/day, s.c.) for 2 days (day 29 and day 30) of 30 days experimental protocol developed significant myocardial infarction that was accompanied with high myocardial oxidative stress and lipid peroxidation, elevated serum markers of cardiac injury, lipid abnormalities, and elevated circulatory levels of C-reactive protein. Pretreatment with low doses of fenofibrate (30 mg/kg/day p.o., 30 days) and rosuvastatin (2 mg/kg/day p.o., 30 days) both alone or in combination markedly prevented isoproterenol-induced myocardial infarction and associated abnormalities while the low-dose combination of fenofibrate and rosuvastatin was more effective. Histopathological study in isoproterenol control rat heart showed necrosis with edema and acute inflammation at the margins of necrotic area. The rat heart from low-dose fenofibrate and rosuvastatin pretreated group showed scanty inflammation and no ischemia. In conclusion, fenofibrate and rosuvastatin pretreatment in low doses might have a therapeutic potential to prevent the pathogenesis of myocardial infarction. Moreover, their combined treatment option might offer superior therapeutic benefits via a marked reduction in myocardial infarct size and oxidative stress, suggesting a possibility of their pleiotropic cardioprotective action at low doses.

Cardiovascular drugs-induced oral toxicities: A murky area to be revisited and illuminated.

Oral health is an imperative part of overall human health. Oral disorders are often unreported, but are highly troublesome to human health in a long-standing situation. A strong association exists between cardiovascular drugs and oral adverse effects. Indeed, several cardiovascular drugs employed clinically have been reported to cause oral adverse effects such as xerostomia, oral lichen planus, angioedema, aphthae, dysgeusia, gingival enlargement, scalded mouth syndrome, cheilitis, glossitis and so forth. Oral complications might in turn worsen the cardiovascular disease condition as some reports suggest an adverse correlation between periodontal oral disease pathogenesis and cardiovascular disease. These are certainly important to be understood for a better use of cardiovascular medicines and control of associated oral adverse effects. This review sheds lights on the oral adverse effects pertaining to the clinical use of cardiovascular drugs. Above and beyond, an adverse correlation between oral disease and cardiovascular disease has been discussed.