Leaf Extracts of Anchomanes difformis Ameliorated Kidney and Pancreatic Damage in Type 2 Diabetes

Natural Products in Renal-Associated Drug Discovery

The global increase in the incidence of kidney failure constitutes a major public health problem. Kidney disease is classified into acute and chronic: acute kidney injury (AKI) is associated with an abrupt decline in kidney function and chronic kidney disease (CKD) with chronic renal failure for more than three months. Although both kidney syndromes are multifactorial, inflammation and oxidative stress play major roles in the diversity of processes leading to these kidney malfunctions. Here, we reviewed various publications on medicinal plants with antioxidant and anti-inflammatory properties with the potential to treat and manage kidney-associated diseases in rodent models. Additionally, we conducted a meta-analysis to identify gene signatures and associated biological processes perturbed in human and mouse cells treated with antioxidants such as epigallocatechin gallate (EGCG), the active ingredient in green tea, and the mushroom Ganoderma lucidum (GL) and in kidney disease rodent models. We identified EGCG- and GL-regulated gene signatures linked to metabolism; inflammation (NRG1, E2F1, NFKB1 and JUN); ion signalling; transport; renal processes (SLC12A1 and LOX) and VEGF, ERBB and BDNF signalling. Medicinal plant extracts are proving to be effective for the prevention, management and treatment of kidney-associated diseases; however, more detailed characterisations of their targets are needed to enable more trust in their application in the management of kidney-associated diseases.

Local anaesthetic procaine derivatives protect rat against diabetic nephropathy via inhibition of DPP-4, inflammation and oxidative stress

Diabetic nephropathy (DN) is a serious devastating disease. However, the current clinical options to treat DN are not adequate. Thus, in the present study, we intend to develop novel series of procaine-embedded thiazole-pyrazoles as protective agent against DN. The compounds were tested for inhibition of dipeptidyl peptidase (DPP)-4, -8, and - 9 enzyme subtypes, where they selectively and potently inhibit DPP-4 as compared to other subtypes. The top three ranked DPP-4 inhibitors (8i, 8e and 8k) were further screened for inhibitory activity against NF-ĸB transcription. Among these three, compound 8i was identified as the most potent NF-ĸB inhibitor. The pharmacological benefit of compound 8i was further established in streptozotocin-induced diabetic nephropathy in rats. Compound 8i showed marked improvements in blood glucose, ALP, ALT, total protein, serum lipid profile such as total cholesterol, triglyceride, HDL levels and renal functions such as urine volume, urinary protein excretion, serum creatinine, blood urea nitrogen and creatinine clearance as compared to nontreated diabetic control group. It also reduces oxidative stress (MDA, SOD and GPx) and inflammation (TNF-α, IL-1β and IL-6) in the rats as compared to disease control group rats. This study demonstrated the discovery of procaine-embedded thiazole-pyrazole compounds as a novel class of agent against diabetic nephropathy.

A Review of Medicinal Plants with Renoprotective Activity in Diabetic Nephropathy Animal Models

Diabetic nephropathy (DN), also recognized as diabetic kidney disease, is a kidney malfunction caused by diabetes mellitus. A possible contributing factor to the onset of DN is hyperglycemia. Poorly regulated hyperglycemia can damage blood vessel clusters in the kidneys, leading to kidney damage. Its treatment is difficult and expensive because its causes are extremely complex and poorly understood. Extracts from medicinal plants can be an alternative treatment for DN. The bioactive content in medicinal plants inhibits the progression of DN. This work explores the renoprotective activity and possible mechanisms of various medicinal plant extracts administered to diabetic animal models. Research articles published from 2011 to 2022 were gathered from several databases including PubMed, Scopus, ProQuest, and ScienceDirect to ensure up-to-date findings. Results showed that medicinal plant extracts ameliorated the progression of DN via the reduction in oxidative stress and suppression of inflammation, advanced glycation end-product formation, cell apoptosis, and tissue injury-related protein expression.

Lactobacillus-fermented yogurt exerts hypoglycemic, hypocholesterolemic, and anti-inflammatory activities in STZ-induced diabetic Wistar rats

Hyperglycemia is a symptom of type 2 diabetes mellitus, a chronic metabolic disease characterized by elevated blood glucose concentrations. Antidiabetic drugs are common treatments for this metabolic disorder; however, they may have unpleasant side effects. This study hypothesized that probiotic fermented products could preserve nutritional value, maintain metabolic homeostasis, and attenuate the inflammatory response associated with diabetes while reducing side effects. Lactobacillus plantarum KU985438 and Lactobacillus rhamnosus KU985439 showed the lowest alfa-amylase enzyme (α-amylase) activity among 8 lactobacilli tested. These 2 strains were used to develop functional fermented milk products, and their antidiabetic efficacy was tested in induced diabetic Wistar rats. The treatment of diabetic rats with L. plantarum KU985438 or L. rhamnosus KU985439 fermented yogurt resulted in a considerable reduction in blood glucose concentrations (136.79% and 145.17%, respectively) and α-amylase concentrations (56.84% and 56.84%, respectively) compared with conventional treatments. Diabetes relief began after 4 days of yogurt consumption compared with drug-based treatment. Significant improvements in both liver and kidney enzyme concentrations were also observed, in addition to a significant increase in high-density lipoprotein cholesterol concentrations and improved lipid profiles. Inhibition in nuclear factor κB and an increase in Bcl-2 concentrations were also detected. Histopathological examination of both hepatic and pancreatic cells revealed the positive effects of the studied treatment compared with standard treatment. Therefore, the selected Lactobacilli, which has hypoglycemic potential, could be used to produce functional nutraceutical antidiabetic supplements.

Oxidative Stress and NRF2/KEAP1/ARE Pathway in Diabetic Kidney Disease (DKD): New Perspectives

Diabetes mellitus (DM) is one of the most debilitating chronic diseases worldwide, with increased prevalence and incidence. In addition to its macrovascular damage, through its microvascular complications, such as Diabetic Kidney Disease (DKD), DM further compounds the quality of life of these patients. Considering DKD is the main cause of end-stage renal disease (ESRD) in developed countries, extensive research is currently investigating the matrix of DKD pathophysiology. Hyperglycemia, inflammation and oxidative stress (OS) are the main mechanisms behind this disease. By generating pro-inflammatory factors (e.g., IL-1,6,18, TNF-α, TGF-β, NF-κB, MCP-1, VCAM-1, ICAM-1) and the activation of diverse pathways (e.g., PKC, ROCK, AGE/RAGE, JAK-STAT), they promote a pro-oxidant state with impairment of the antioxidant system (NRF2/KEAP1/ARE pathway) and, finally, alterations in the renal filtration unit. Hitherto, a wide spectrum of pre-clinical and clinical studies shows the beneficial use of NRF2-inducing strategies, such as NRF2 activators (e.g., Bardoxolone methyl, Curcumin, Sulforaphane and their analogues), and other natural compounds with antioxidant properties in DKD treatment. However, limitations regarding the lack of larger clinical trials, solubility or delivery hamper their implementation for clinical use. Therefore, in this review, we will discuss DKD mechanisms, especially oxidative stress (OS) and NRF2/KEAP1/ARE involvement, while highlighting the potential of therapeutic approaches that target DKD via OS.

Nephroprotective Plants: A Review on the Use in Pre-Renal and Post-Renal Diseases

Kidney diseases are expected to become the fifth leading cause of death by 2040. Several physiological failures classified as pre-, intra-, and post-renal factors induce kidney damage. Diabetes, liver pathologies, rhabdomyolysis, and intestinal microbiota have been identified as pre-renal factors, and lithiasis or blood clots in the ureters, prostate cancer, urethral obstructions, prostate elongation, and urinary tract infections are post-renal factors. Additionally, the nephrotoxicity of drugs has been highlighted as a crucial factor inducing kidney injuries. Due to the adverse effects of drugs, it is necessary to point to other alternatives to complement the treatment of these diseases, such as nephroprotective agents. Plants are a wide source of nephroprotective substances and can have beneficial effects in different levels of the physiological pathways which lead to kidney damage. In traditional medicines, plants are used as antioxidants, anti-inflammatories, diuretics, and anticancer agents, among other benefits. However, the mechanism of action of some plants empirically used remains unknown and scientific data are required to support their nephroprotective effects. The present work reviewed the plants with a beneficial effect on kidney diseases. The classification of nephroprotective plants according to the clinical definition of pre-renal, intrinsic, and post-renal factors is proposed to orient their use as complementary treatments.

The relationship between B-cell lymphoma 2, interleukin-1β, interleukin-17, and interleukin-33 and the development of diabetic nephropathy

BACKGROUND

Diabetic nephropathy (DN) is among the main complications of diabetes mellitus and has been a major factor of renal failure. This study was designed to address the association between beta-cell lymphoma-2 (Bcl-2), interleukin (IL)-1β, IL-17, and IL-33 and the development of DN.

METHODS

In this study, 20 healthy volunteers and 100 patients were enrolled. According to their biochemical markers, the patients were categorized into five groups: diabetic, chronic renal disease, diabetic chronic renal disease, end-stage renal disease, and diabetic end-stage renal disease.

RESULTS

Our results showed a noticeable elevation in IL-1β and IL-17 levels and a reduction in IL-33 and Bcl-2 levels in all investigated groups compared with those in the healthy group. Positive correlations were found between IL-1β and fasting blood sugar and between creatinine levels and IL-17, HbA1c%, and sodium levels. However, negative correlations were found between IL-33 and urea and sodium concentrations and between Bcl-2 and HbA1c% and creatinine levels.

CONCLUSIONS

The present data revealed a marked relationship between Bcl-2, IL-1β, IL-17, and IL-33 levels and the onset and progression of DN. Understanding the molecular pathways of these processes could be translated into the development of therapeutic strategies.

Ameliorative effects of Anchomanes difformis aqueous extract against oxidative stress in the testes and epididymis of streptozotocin-induced diabetic male Wistar rats

Hyperglycemia is a central trait of diabetes mellitus (DM) and is linked to an increase in free radical generation and oxidative stress in the testes, resulting in testicular tissue damage and male infertility. Synthetic medicines are commonly used to manage diabetes; however, they are costly and associated with adverse effects. As a result, the search for a safer and affordable alternative from medicinal plants that contain antioxidants has become imperative to scavenge free radicals caused by hyperglycaemia, thereby alleviating male reproductive dysfunction. Therefore, the present aimed to investigate the ameliorative effects of Anchomanes difformis aqueous extract against oxidative stress in the testes and epididymis of streptozotocin-induced diabetic male Wistar rats. A total of 64 male Wistar rats (eight weeks old) weighing 180 ± 10 mg/kg were divided into seven groups at random. Type 2 diabetic mellitus (T2DM) was induced by streptozotocin (STZ) and a 10% fructose injection intraperitoneally using 40 mg/kg body weight rats. The levels of malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD) activity, reduced glutathione (GSH) concentration, and ferric reducing antioxidant (FRAP) as well as 2, 2-diphenyl-1-picrylhydrazyl (DPPH) values were used to establish the testicular oxidative status. It was found that A. difformis extract significantly (p < 0.05) lowered MDA levels in diabetic rats. Both CAT and SOD activity were significantly (p < 0.05) lower following induction of DM and increased (p < 0.05) after treating with A. difformis. The findings of this study show that A. difformis extract could be a promising source of lead compounds for the development of a therapeutic agent to treat male infertility caused by DM complications.

NADH/NAD+ Redox Imbalance and Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common and severe complication of diabetes mellitus. If left untreated, DKD can advance to end stage renal disease that requires either dialysis or kidney replacement. While numerous mechanisms underlie the pathogenesis of DKD, oxidative stress driven by NADH/NAD⁺ redox imbalance and mitochondrial dysfunction have been thought to be the major pathophysiological mechanism of DKD. In this review, the pathways that increase NADH generation and those that decrease NAD⁺ levels are overviewed. This is followed by discussion of the consequences of NADH/NAD⁺ redox imbalance including disruption of mitochondrial homeostasis and function. Approaches that can be applied to counteract DKD are then discussed, which include mitochondria-targeted antioxidants and mimetics of superoxide dismutase, caloric restriction, plant/herbal extracts or their isolated compounds. Finally, the review ends by pointing out that future studies are needed to dissect the role of each pathway involved in NADH-NAD⁺ metabolism so that novel strategies to restore NADH/NAD⁺ redox balance in the diabetic kidney could be designed to combat DKD.