Synergistic effect of micronutrients and metformin in alleviating diabetic nephropathy and cardiovascular Dysfunctioning in diabetic rat

Vitamin B1 and calcitriol enhance glibenclamide suppression of diabetic nephropathy: Role of HMGB1/TLR4/NF-κB/TNF-α/Nrf2/α-SMA trajectories

Glibenclamide is one of the most prescribed insulin secretagogues in diabetes due to its low cost, but its efficacy on suppressing diabetic complications is limited. Here, we examine whether addition of either vitamin B1 or calcitriol to glibenclamide could produce more suppression of diabetic nephropathy. Type 2 diabetes was induced by high fructose (10 % in drinking water), high salt (3 % in diet), and high fat diet (25 % in diet) for 3 weeks, followed by single dose of STZ (40 mg/kg, i.p.). Diabetic rats were treated with either glibenclamide (0.6 mg/kg), vitamin B1 (70 mg/kg), glibenclamide/vitamin B1, calcitriol (0.1 μg/kg), or glibenclamide/calcitriol. Addition of either vitamin B1 or calcitriol to glibenclamide therapy enabled more suppression of diabetic nephropathy development as evidenced by more preserved creatinine clearance and less renal damage scores. Combination therapy resulted in mild enhancement in the effect of glibenclamide on glucose tolerance without affecting the area under the curve. Combination therapy was associated with more suppression of inflammatory cascades as evidenced by reducing the expression of high mobility group box-1 (HMGB1), toll-like receptor-4 (TLR4), nuclear factor-kappa B (NF-κB), and tumor necrosis factor-α (TNF-α). In addition, combination therapy enhanced the antioxidant mechanisms as evidenced by increased expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and glutathione content and reducing malondialdehyde and nitric oxide levels. Furthermore, combination therapy provided more suppression of fibrotic pathways as appear from reducing collagen deposition and the expression of α- smooth muscle actin (α-SMA). In conclusion, addition of vitamin B1 or calcitriol to glibenclamide therapy can enhance the therapeutic efficiency of glibenclamide in suppressing diabetic nephropathy progression to the same extend, the protective effect is mediated through modulating HMGB1/TLR4/NF-κB/TNF-α/Nrf2/α-SMA trajectories.

Metformin beyond an anti-diabetic agent: A comprehensive and mechanistic review on its effects against natural and chemical toxins

In addition to the anti-diabetic effect of metformin, a growing number of studies have shown that metformin has some exciting properties, such as anti-oxidative capabilities, anticancer, genomic stability, anti-inflammation, and anti-fibrosis, which have potent, that can treat other disorders other than diabetes mellitus. We aimed to describe and review the protective and antidotal efficacy of metformin against biologicals, chemicals, natural, medications, pesticides, and radiation-induced toxicities. A comprehensive search has been performed from Scopus, Web of Science, PubMed, and Google Scholar databases from inception to March 8, 2023. All in vitro, in vivo, and clinical studies were considered. Many studies suggest that metformin affects diseases other than diabetes. It is a radioprotective and chemoprotective drug that also affects viral and bacterial diseases. It can be used against inflammation-related and apoptosis-related abnormalities and against toxins to lower their effects. Besides lowering blood sugar, metformin can attenuate the effects of toxins on body weight, inflammation, apoptosis, necrosis, caspase-3 activation, cell viability and survival rate, reactive oxygen species (ROS), NF-κB, TNF-α, many interleukins, lipid profile, and many enzymes activity such as catalase and superoxide dismutase. It also can reduce the histopathological damages induced by many toxins on the kidneys, liver, and colon. However, clinical trials and human studies are needed before using metformin as a therapeutic agent against other diseases.

Ameliorative effect of Nigella sativa conjugated silver nanoparticles against chromium-induced hepatotoxicity and renal toxicity in mice

Hexavalent chromium induces oxidative stress in the liver and kidney. Therefore an in vivo study was designed to investigate the modulatory effect of biosynthesized AgNP against Cr (VI) induced hepatotoxicity and nephrotoxicity. The organs index, serum level of ALT, AST, ALP, MDA, total protein and creatinine were measured. The histopathology and micrometry of the liver and kidney were examined. The liver index was significantly increased (0.098 ± 0.13 g) with slight increase in kidney index in Cr exposed group. The serum level of ALT (163.0 ± 5.5 U/L), AST (484.0 ± 10.7 U/L), ALP (337.6 ± 9.6 U/L), MDA (641.2 ± 29.2 U/L), and creatinine (2.9 ± 0.2 mg/dL) were significantly increased (P ≤ 0.05) with significant decrease in total protein level (2.9 ± 0.2 g/dL) (P ≤ 0.05) in chromium treated group. In histopathology, distorted hepatic cords, necrosis, damaged glomerulus and Bowman's capsule were observed. Micrometric studies of the liver and kidney showed significant increase in size of hepatocytes (1188.2 ± 467.7 µ²) and their nuclei (456.4 ± 206.7 µ²), ACSA of Bowman's capsule (11835.5 ± 336.7 µ²) and glomerulus (9051.8 ± 249.8 µ²⁾ in Cr (VI) treated group. The size of brush border (10.1 ± 3.0 µ) was significantly reduced in Cr (VI) treated group however the ACSA of lumen was not significantly changed. With the administration of NSSE and Nigella sativa AgNPs, decreased the oxidative damage caused by Cr (V).

The Nicotinamide/Streptozotocin Rodent Model of Type 2 Diabetes: Renal Pathophysiology and Redox Imbalance Features

Diabetic nephropathy (DN) is a common complication of diabetes mellitus. While there has been a great advance in our understanding of the pathogenesis of DN, no effective managements of this chronic kidney disease are currently available. Therefore, continuing to elucidate the underlying biochemical and molecular mechanisms of DN remains a constant need. In this regard, animal models of diabetes are indispensable tools. This review article highlights a widely used rodent model of non-obese type 2 diabetes induced by nicotinamide (NA) and streptozotocin (STZ). The mechanism underlying diabetes induction by combining the two chemicals involves blunting the toxic effect of STZ by NA so that only a percentage of β cells are destroyed and the remaining viable β cells can still respond to glucose stimulation. This NA-STZ animal model, as a platform for the testing of numerous antidiabetic and renoprotective materials, is also discussed. In comparison with other type 2 diabetic animal models, such as high-fat-diet/STZ models and genetically engineered rodent models, the NA-STZ model is non-obese and is less time-consuming and less expensive to create. Given that this unique model mimics certain pathological features of human DN, this model should continue to find its applications in the field of diabetes research.

Effects of Metformin on Renal Function, Cardiac Function, and Inflammatory Response in Diabetic Nephropathy and Its Protective Mechanism

Objective. To investigate the effect of metformin on renal function, cardiac function, and inflammatory response in diabetic nephropathy and its protective mechanism. Methods. A total of 88 patients with diabetic nephropathy who were admitted to our hospital from April 2019 to October 2020 were recruited and grouped according to different treatment methods, namely, the experimental group ( $n=44$ ) and the control group ( $n=44$ ). The patients in the experimental group were treated with metformin, and the patients in the control group were treated with liraglutide injection (nonmetformin). Left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), left ventricular end-systolic diameter (LVESD), and inflammatory response (hs-CRP, TNF-α, IL-6) were compared. Results. Compared with corresponding values before treatment, BUN, Scr, hs-CRP, TNF-α, IL-6, LVEDD, and LVESD were decreased after treatment, whereas LVEF was increased (all $P<0.05$ ), with significant change in the experimental group (all $P<0.001$ ). Conclusion. Metformin can effectively improve the level of renal function and cardiac function in patients with diabetic nephropathy and help patients control and reduce the body’s inflammatory response, and its therapeutic efficacy is superior to that of liraglutide injection.