Nicousamide normalizes renovascular hypertension in two-kidney one-clip hypertensive rats

Salubrious effects of ulinastatin and quercetin alone or in combination in endothelial dysfunction and vascular dementia

BACKGROUND

Vascular dementia is the second most prevalent form of dementia. Hypertension is the leading risk factor for endothelial dysfunction and the progression of dementia that is of vascular origin. This study investigates the role of ulinastatin (UTI) and quercetin alone as well as in combination in hypertension-induced endothelial dysfunction and vascular dementia (VaD).

METHOD

Two-kidney one-clip (2K1C) renovascular model was set up to induce hypertension in the Albino Wistar rats (males). Rats were assessed for mean arterial blood pressure, behavioral function (Morris water maze, attention set-shifting tests), vascular endothelial function, and biochemical levels (aortic superoxide anion and serum nitrite/nitrate), as well as brains' thiobarbituric acid reactive species-TBARS, reduced glutathione-GSH, interleukin-6, 10, tumor necrosis factor-TNF-α and acetylcholinesterase-AChE). UTI (10,000 U/kg, ip) and quercetin (60 mg/kg) were used alone and in combination for treatment. Donepezil (0.5 mg/kg) was used as a positive control.

RESULTS

2K1C rats showed impairment in learning, memory, executive functioning, and reversal learning. These rats further showed endothelial dysfunction as well as an increase in mean arterial blood pressure, brains' oxidative stress, inflammation, and AChE-activity. Treatment with UTI and quercetin alone as well in combination significantly attenuated the 2K1C model induced impairments in the behavioural, biochemical, and endothelial parameters.

CONCLUSION

2K1C renovascular hypertension-induced impairment in behavioural, biochemical, and endothelial parameters were attenuated by the treatment with UTI and quercetin alone as well as in combination. Therefore, the utility of these agents might be studied further to understand their full potential in hypertension-induced VaD.

Recent Advances in the Knowledge of Naturally-derived Bioactive Compounds as Modulating Agents of the Renin-angiotensin-aldosterone System: Therapeutic Benefits in Cardiovascular Diseases

BACKGROUND

One of the biggest challenges to public health worldwide is to reduce the number of events and deaths related to the cardiovascular diseases. Numerous approaches have been applied to reach this goal, and drug treatment intervention has been indispensable along with an effective strategy for reducing both cardiovascular morbidity and mortality. Renin-angiotensin-aldosterone system (RAAS) blockade is currently one of the most important targets of cardiovascular drug therapy. Many studies have proven the valuable properties of naturally-derived bioactive compounds to treat cardiovascular diseases.

METHODS

The goal of this review, therefore, is to discuss the recent developments related to medicinal properties about natural compounds as modulating agents of the RAAS, which have made them an attractive alternative to be available to supplement the current therapy options.

RESULTS

Data has shown that bioactive compounds isolated from several natural products act either by inhibiting the angiotensin-converting enzyme or directly by modulating the AT1 receptors of angiotensin II, which consequently changes the entire classical axis of this system.

CONCLUSION

While there are a few evidence about the positive actions of different classes of secondary metabolites for the treatment of cardiovascular and renal diseases, data is scarce about the clinical assays established to demonstrate their value in humans.

Nicousamide protects kidney podocyte by inhibiting the TGFβ receptor II phosphorylation and AGE-RAGE signaling

Nicousamide, a clinical phase II renal protective new drug, has been demonstrated to have renal protective effect on diabetic nephropathy (DN) by experimental animal model. Its known molecular mechanisms include AGE formation blocking and moderately decreasing the blood pressure. Nicousamide shows potential on attenuating albuminuria, thereby suggests it might have protective effect on podocytes. The aim of present study was to investigate whether nicousamide could protect integrity of podocytes, and further its protection mechanisms. Sprague-Dawley (SD) rats were induced to DN by streptozotocin, and nicousamide (20 and 40 mg/kg) was orally administrated for 20 weeks. Every five weeks, the albuminuria was measured, and renal pathology was evaluated at the end of experiment. Real-time PCR and immunofluorescence were used to test expression of podocyte marker nephrin, CD2AP and podocine in rat kidney tissues. Western blot was used to test the activation and phosphorylation of TGFβ1-smad signaling pathway. surface plasmon resonance (SPR) technology was used to analyze whether nicousamide can interact with TGFβ1 receptor II (TGFβ RII) and receptor for advanced glycation endproducts (RAGE). Results demonstrate that nicousamide significantly reduces albuminuria and ameliorate the glomerulosclerosis in DN rats. RT-PCR and immunofluorescence demonstrate that nicousamide can increase the expression of podocyte markers and keep podocyte effacement. Phosphorylation of TGFβ RII and smad2 in rat kidney was inhibited by nicousamide dose dependently. SPR demonstrate that nicousamide have strong binding capability with hRAGE with Kd approximate 6 μM. These results indicate a protective effect of nicousamide against podocyte injury, and this effect might contribute from suppression of TGFβ-involved fibrosis and AGE-RAGE signaling activation.