Metformin ameliorates diabetic nephropathy in a rat model of low-dose streptozotocin-induced diabetes

Role of Metformin in Preventing New-Onset Chronic Kidney Disease in Patients with Type 2 Diabetes Mellitus

Background: Recent evidence supports the protective role of metformin on kidney function in patients with type 2 diabetes mellitus. However, its potential to prevent new-onset chronic kidney disease (CKD) in patients with type 2 diabetes mellitus with normal renal function remains unclear. Therefore, this study aimed to investigate whether metformin could prevent the development of new-onset CKD in such patients. Methods: This retrospective, observational, multicenter cohort study included 316,693 patients with type 2 diabetes mellitus. After matching using the inverse probability of treatment weighting, 9109 metformin users and 1221 nonusers were analyzed. The primary outcomes were an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2, urinary albumin-to-creatinine ratio of ≥30 mg/g, and a composite outcome defined as new-onset CKD. Results: The multivariable Cox survival model showed that metformin users had significantly better renal outcomes, with a notably lower risk of sustained eGFR of <60 mL/min/1.73 m2 (hazard ratio (HR), 0.71; 95% confidence interval (CI), 0.56-0.90) and new CKD onset (HR, 0.78; 95% CI, 0.65-0.94). Conclusions: Metformin plays a key role in delaying renal events in individuals with type 2 diabetes mellitus and in those with initially normal renal function.

Metformin effectively alleviates the symptoms of Alzheimer in rats by lowering amyloid β deposition and enhancing the insulin signal

Alzheimer's disease (AD) exhibits distinct biochemical and histopathological attributes, encompassing cellular, neuronal, and oxidative impairment. There is also an abnormal buildup, misfolding and clumping of amyloid β (Aβ). The present study aimed to explore the influence of the antihyperglycemic agent metformin on rats with AD-like symptoms, while also elucidating the intricate relationship between insulin resistance and AD. The rats were categorized into five groups: a control group, a saline-administered group, a metformin-treated group, AD-model rats, and AD-rats treated with a 200 mg/kg dose of metformin. Cognitive impairment was rated using the classical labyrinth test. Moreover, serum biochemical parameters, encompassing glucose levels, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Glycated hemoglobin (HbA1c), lipid profile, kidney, and liver function, were evaluated. Additionally, oxidative, antioxidant, and neurotransmitter parameters were measured in hippocampus tissues. Also, the Aβ and insulin receptor substrate 2 (IRS-2) were measured by immunoblotting. Besides hippocampal histopathology, glial fibrillary acidic protein (GFAP) and calretinin immunoreactivity were monitored. The study findings disclosed deficits in memory and learning capabilities among AD rats. Furthermore, AD-afflicted rats exhibited heightened glucose levels, elevated HOMA-IR and HbA1c values, alongside compromised liver, and kidney functions. Additionally, an upsurge in oxidative stress coincided with a notable reduction in the antioxidant system and neurotransmitters activities. The levels of Aβ deposition increased, while IRS-2 expression subsided, accompanied by alterations in the hippocampal structure and neuronal damage. These changes were paralleled by an intensification in GFAP reactivity and a detracting in calretinin reactivity. Metformin was altogether able to move forward cognitive execution by means of bringing down oxidative stress and Aβ conglomeration. Furthermore, metformin was able to improve neurotransmitters and insulin signals. AD, glucose impairment, and brain insulin resistance are completely interlinked, and future AD medications may be inspired by diabetic medication.

Tiliroside protects against diabetic nephropathy in streptozotocin-induced diabetes rats by attenuating oxidative stress and inflammation

BACKGROUND

Diabetic nephropathy (DN), affecting half of diabetic patients and contributing significantly to end-stage kidney disease, poses a substantial medical challenge requiring dialysis or transplantation. The nuanced onset and clinical progression of kidney disease in diabetes involve consistent renal function decline and persistent albuminuria.

AIM

To investigate Tiliroside's (Til) protective effect against diabetic nephropathy (DN) in rats under diabetic conditions.

METHODS

Five groups of six rats each were included in this study: Rats treated with DMSO by intraperitoneal injection as controls, those treated with STZ by intraperitoneal injection, those treated with STZ + Til (25 mg/kg body weight [bwt]) or Til (50 mg/kg bwt), and those treated with anti-diabetic medication glibenclamide (600 μg/kg bwt). Biochemical markers, fasting blood glucose, food intake, kidney weight, antioxidant enzymes, inflammatory and fibrotic markers, and renal injury were monitored in different groups. Molecular docking analysis was performed to identify the interactions between Til and its targeted biomarkers.

RESULTS

Til significantly reduced biochemical markers, fasting blood glucose, food intake, and kidney weight and elevated antioxidant enzymes in diabetic rats. It also mitigated inflammatory and fibrotic markers, lessened renal injury, and displayed inhibitory potential against crucial markers associated with DN as demonstrated by molecular docking analysis.

CONCLUSION

These findings suggest Til's potential as a therapeutic agent for DN treatment, highlighting its promise for future drug development.

The effects of Cannabis sativa and cannabinoids on the inhibition of pancreatic lipase - An enzyme involved in obesity

INTRODUCTION

Obesity is a chronic noncommunicable disease characterized by excessive body fat that can have negative health consequences. Obesity is a complex disease caused by a combination of genetic, environmental, and lifestyle factors. It is characterized by a discrepancy between caloric intake and expenditure. Obesity increases the risk of acquiring major chronic diseases, including heart disease, stroke, cancer, and Type 2 diabetes mellitus (T2DM). Currently, the inhibition of pancreatic lipases (PL) is a promising pharmacological therapy for obesity and weight management. In this study, the inhibition of pancreatic lipase by Cannabis sativa (C. sativa) plant extract and cannabinoids was investigated.

METHODS

The inhibitory effect was assessed using p-nitrophenyl butyrate (pNPB), and the results were obtained by calculating the percentage relative activity and assessed using one-way analysis of variance (ANOVA). Kinetic studies and spectroscopy techniques were used to evaluate the mode of inhibition. Diet-induced; and diabetic rat models were studied to evaluate the direct effects of C. sativa extract on PL activity.

RESULTS

Kinetic analyses showed that the plant extracts inhibited pancreatic lipase, with tetrahydrocannabinol (THC) and cannabinol (CBN) being the potential cause of the inhibition noted for the C. sativa plant extract. CBN and THC inhibited the pancreatic lipase activity in a competitive manner, with the lowest residual enzyme activity of 52 % observed at a 10 μg/mL concentration of CBN and 39 % inhibition at a 25 μg/mL concentration of THC. Circular dichroism (CD) spectroscopy revealed that the inhibitors caused a change in the enzyme's secondary structure. At low concentrations, THC showed potential for synergistic inhibition with orlistat. C.sativa treatment in an in vivo rat model confirmed its inhibitory effects on pancreatic lipase activity.

CONCLUSION

The findings in this study provided insight into the use of cannabinoids as pancreatic lipase inhibitors and the possibility of using these compounds to develop new pharmacological treatments for obesity.

Potentials of Natural Antioxidants in Reducing Inflammation and Oxidative Stress in Chronic Kidney Disease

Chronic kidney disease (CKD) presents a substantial global public health challenge, with high morbidity and mortality. CKD patients often experience dyslipidaemia and poor glycaemic control, further exacerbating inflammation and oxidative stress in the kidney. If left untreated, these metabolic symptoms can progress to end-stage renal disease, necessitating long-term dialysis or kidney transplantation. Alleviating inflammation responses has become the standard approach in CKD management. Medications such as statins, metformin, and GLP-1 agonists, initially developed for treating metabolic dysregulation, demonstrate promising renal therapeutic benefits. The rising popularity of herbal remedies and supplements, perceived as natural antioxidants, has spurred investigations into their potential efficacy. Notably, lactoferrin, Boerhaavia diffusa, Amauroderma rugosum, and Ganoderma lucidum are known for their anti-inflammatory and antioxidant properties and may support kidney function preservation. However, the mechanisms underlying the effectiveness of Western medications and herbal remedies in alleviating inflammation and oxidative stress occurring in renal dysfunction are not completely known. This review aims to provide a comprehensive overview of CKD treatment strategies and renal function preservation and critically discusses the existing literature's limitations whilst offering insight into the potential antioxidant effects of these interventions. This could provide a useful guide for future clinical trials and facilitate the development of effective treatment strategies for kidney functions.

Bidirectional modulation of TCA cycle metabolites and anaplerosis by metformin and its combination with SGLT2i

BACKGROUND

Metformin and sodium-glucose-cotransporter-2 inhibitors (SGLT2i) are cornerstone therapies for managing hyperglycemia in diabetes. However, their detailed impacts on metabolic processes, particularly within the citric acid (TCA) cycle and its anaplerotic pathways, remain unclear. This study investigates the tissue-specific metabolic effects of metformin, both as a monotherapy and in combination with SGLT2i, on the TCA cycle and associated anaplerotic reactions in both mice and humans.

METHODS

Metformin-specific metabolic changes were initially identified by comparing metformin-treated diabetic mice (MET) with vehicle-treated db/db mice (VG). These findings were then assessed in two human cohorts (KORA and QBB) and a longitudinal KORA study of metformin-naïve patients with Type 2 Diabetes (T2D). We also compared MET with db/db mice on combination therapy (SGLT2i + MET). Metabolic profiling analyzed 716 metabolites from plasma, liver, and kidney tissues post-treatment, using linear regression and Bonferroni correction for statistical analysis, complemented by pathway analyses to explore the pathophysiological implications.

RESULTS

Metformin monotherapy significantly upregulated TCA cycle intermediates such as malate, fumarate, and α-ketoglutarate (α-KG) in plasma, and anaplerotic substrates including hepatic glutamate and renal 2-hydroxyglutarate (2-HG) in diabetic mice. Downregulated hepatic taurine was also observed. The addition of SGLT2i, however, reversed these effects, such as downregulating circulating malate and α-KG, and hepatic glutamate and renal 2-HG, but upregulated hepatic taurine. In human T2D patients on metformin therapy, significant systemic alterations in metabolites were observed, including increased malate but decreased citrulline. The bidirectional modulation of TCA cycle intermediates in mice influenced key anaplerotic pathways linked to glutaminolysis, tumorigenesis, immune regulation, and antioxidative responses.

CONCLUSION

This study elucidates the specific metabolic consequences of metformin and SGLT2i on the TCA cycle, reflecting potential impacts on the immune system. Metformin shows promise for its anti-inflammatory properties, while the addition of SGLT2i may provide liver protection in conditions like metabolic dysfunction-associated steatotic liver disease (MASLD). These observations underscore the importance of personalized treatment strategies.

Empagliflozin alone and in combination with metformin mitigates diabetes-associated renal complications

Diabetes mellitus is a major public health concern, often leading to undiagnosed micro- and macrovascular complications, even in patients with controlled blood glucose levels. Recent evidence suggests that empagliflozin and metformin have renoprotective effects in addition to their hypoglycemic action. This study investigated the potential protective effect of empagliflozin and metformin on diabetic renal complications. Forty-two adult male Sprague Dawley rats were randomized into six groups: normal control, diabetic control, metformin (250 mg/kg), empagliflozin (10 mg/kg), and combination therapy groups. Type 2 diabetes was induced in rats by a single intraperitoneal injection of streptozotocin (40 mg/kg) following two weeks of 10% fructose solution in their drinking water. Blood glucose, creatinine, urea nitrogen, inflammatory markers (IL-6, TNF-α), and renal tissue caspase-3 were assessed after eight weeks. Blood glucose, urea, creatinine, serum IL-6, TNF-α, and tissue caspase-3 were significantly decreased in the treatment groups compared to the diabetic group. The histopathological findings revealed that treatment with empagliflozin and/or metformin improved the damage in the renal tissue caused by diabetes-induced nephropathy. Moreover, co-administration of empagliflozin and metformin resulted in even better outcomes. Our data revealed that empagliflozin and metformin could improve renal function and decrease inflammation and apoptosis in diabetic animals, delaying the progression of diabetic nephropathy. Combined treatment with metformin and empagliflozin proved to have an additive protective action on renal tissue.

Nephroprotective Effect of Hibiscus Sabdariffa Leaf Flavonoid Extracts via KIM-1 and TGF-1β Signaling Pathways in Streptozotocin-Induced Rats

Diabetes-induced kidney damage represents a substantial health hazard, emphasizing the imperative to explore potential therapeutic interventions. This study investigates the nephroprotective activity of flavonoid-rich extracts from Hibiscus sabdariffa leaves in streptozotocin-induced diabetic rats. The flavonoid-rich extracts of H. sabdariffa leaves was obtained using a standard procedure. The animals were induced with streptozotocin and thereafter treated with both low (LDHSFL) and high doses (HDHSFL) of flavonoid-rich extracts from H. sabdariffa leaves and metformin (MET), and other groups are diabetic control (DC) and normal control (NC). The study assesses diverse renal parameters, encompassing kidney redox stress biomarkers, serum electrolyte levels, kidney inflammatory biomarkers, serum concentrations of creatinine, urea, and uric acid, kidney phosphatase activities, renal histopathology, and relative gene expressions of kidney injury molecule-1 (KIM-1) and transforming growth factor beta-1 (TGF-1β), comparing these measurements with normal and diabetic control groups (NC and DC). The findings indicate that the use of extracts from H. sabdariffa leaves markedly (p < 0.05) enhanced renal well-being by mitigating nephropathy, as demonstrated through the adjustment of various biochemical and gene expression biomarkers, indicating a pronounced antioxidative and anti-inflammatory effect, improved kidney morphology, and mitigation of renal dysfunction. These findings suggest that H. sabdariffa leaf flavonoid extracts exhibit nephroprotective properties, presenting a potential natural therapeutic approach for the treatment of diabetic nephropathy.

Methylglyoxal and Advanced Glycation End Products (AGEs): Targets for the Prevention and Treatment of Diabetes-Associated Bladder Dysfunction?

Methylglyoxal (MGO) is a highly reactive α-dicarbonyl compound formed endogenously from 3-carbon glycolytic intermediates. Methylglyoxal accumulated in plasma and urine of hyperglycemic and diabetic individuals acts as a potent peptide glycation molecule, giving rise to advanced glycation end products (AGEs) like arginine-derived hydroimidazolone (MG-H1) and carboxyethyl-lysine (CEL). Methylglyoxal-derived AGEs exert their effects mostly via activation of RAGE, a cell surface receptor that initiates multiple intracellular signaling pathways, favoring a pro-oxidant environment through NADPH oxidase activation and generation of high levels of reactive oxygen species (ROS). Diabetic bladder dysfunction is a bothersome urological complication in patients with poorly controlled diabetes mellitus and may comprise overactive bladder, urge incontinence, poor emptying, dribbling, incomplete emptying of the bladder, and urinary retention. Preclinical models of type 1 and type 2 diabetes have further confirmed the relationship between diabetes and voiding dysfunction. Interestingly, healthy mice supplemented with MGO for prolonged periods exhibit in vivo and in vitro bladder dysfunction, which is accompanied by increased AGE formation and RAGE expression, as well as by ROS overproduction in bladder tissues. Drugs reported to scavenge MGO and to inactivate AGEs like metformin, polyphenols, and alagebrium (ALT-711) have shown favorable outcomes on bladder dysfunction in diabetic obese leptin-deficient and MGO-exposed mice. Therefore, MGO, AGEs, and RAGE levels may be critically involved in the pathogenesis of bladder dysfunction in diabetic individuals. However, there are no clinical trials designed to test drugs that selectively inhibit the MGO-AGEs-RAGE signaling, aiming to reduce the manifestations of diabetes-associated bladder dysfunction. This review summarizes the current literature on the role of MGO-AGEs-RAGE-ROS axis in diabetes-associated bladder dysfunction. Drugs that directly inactivate MGO and ameliorate bladder dysfunction are also reviewed here.

Swertiamarin mitigates nephropathy in high-fat diet/streptozotocin-induced diabetic rats by inhibiting the formation of advanced glycation end products

CONTEXT

The molecular mechanism by which Swertiamarin (SM) prevents advanced glycation end products (AGEs) induced diabetic nephropathy (DN) has never been explored.

OBJECTIVE

To evaluate the effect of SM in preventing the progression of DN in high fat diet-streptozotocin-induced diabetic rats.

MATERIALS AND METHODS

After 1 week of acclimatisation, the rats were divided randomly into five groups as follows: (1) Control group, which received normal chow diet; (2) High-fat diet (HFD) group which was fed diet comprising of 58.7% fat, 27.5% carbohydrate and 14.4% protein); (3) Aminoguanidine (AG) group which received HFD + 100 mg/k.b.w.AG (intraperitoneal); (4) Metformin (Met) group which received HFD + 70 mg/k.b.w. the oral dose of Met and (5) SM group which was supplemented orally with 50 mg/k.b.w.SM along with HFD. After 12 weeks all HFD fed animals were given a single 35 mg/k.b.w. dose of streptozotocin with continuous HFD feeding for additional 18 weeks. Later, various biochemical assays, urine analyses, histopathological analysis of kidneys, levels of AGEs, expression of various makers, and in-silico analysis were performed.

RESULTS

The diabetic group demonstrated oxidative stress, increased levels of AGEs, decreased renal function, fibrosis in the renal tissue, higher expression of the receptor for advanced glycation end products (RAGE), which were ameliorated in the SM treated group. In-silico analysis suggests that SM can prevent the binding of AGEs with RAGE.

CONCLUSIONS

SM ameliorated DN by inhibiting the oxidative stress induced by AGEs.HighlightsSM reduces the levels of hyperglycaemia-induced advanced glycation end products in serum and renal tissue.SM prevents renal fibrosis by inhibiting the EMT in the kidney tissue.The in-silico analysis proves that SM can inhibit the binding of various AGEs with RAGE, thereby inhibiting the AGE-RAGE axis.

Simvastatin mitigates diabetic nephropathy by upregulating farnesoid X receptor and Nrf2/HO-1 signaling and attenuating oxidative stress and inflammation in rats

Diabetic nephropathy is one of the complications of diabetes that affects the kidney and can result in renal failure. The cholesterol-lowering drug simvastatin (SIM) has shown promising effects against diabetic nephropathy (DN). This study evaluated the protective role of SIM on DN, pointing to the involvement of farnesoid X receptor (FXR) and Nrf2/HO-1 signaling in attenuating inflammatory response, oxidative injury, and tissue damage in streptozotocin-induced diabetic rats. SIM was supplemented orally for 8 weeks, and samples were collected for analysis. SIM effectively ameliorated hyperglycemia, kidney hypertrophy, body weight loss, and tissue injury and fibrosis in diabetic animals. SIM mitigated oxidative stress (OS), inflammatory response, and cell death, as evidenced by the suppressed malondialdehyde, nitric oxide, myeloperoxidase, NF-kB, TNF-α, IL-1β, CD68, Bax, and caspase-3 in the diabetic kidney. These effects were linked to suppressed Keap1, upregulated FXR, Nrf2, and HO-1, and enhanced antioxidant defenses and Bcl-2. The in silico findings revealed the binding affinity of SIM with NF-kB, caspase-3, Keap1, HO-1, and FXR. In conclusion, SIM protects against DN by attenuating hyperglycemia, kidney injury, fibrosis, inflammation, and OS, and upregulating antioxidants, FXR, and Nrf2/HO-1 signaling.

Alzheimer's disease-related brain insulin resistance and the prospective therapeutic impact of metformin

Besides COVID-19, two of the most critical outbreaks of our day are insulin resistance, type 2 diabetes mellitus (T2DM), and Alzheimer's disease (AD). Each disease's pathophysiology is well established. Furthermore, a substantial overlap between them has coexisted. Uncertainty remains on whether T2DM and AD are parallel illnesses with the same origin or separate illnesses linked through violent pathways. The current study was aimed at testing whether the insulin resistance in the brain results in AD symptoms or not. Insulin resistance was induced in the brains of rats using a single intracerebroventricular streptozotocin (STZ) dose. We then measured glucose, insulin receptor substrate 2 (IRS-2), amyloid β (Aβ) deposition, and tau phosphorylation in the brain to look for signs of insulin resistance and AD. The results of this study indicated that a single dose of STZ was able to induce insulin resistance in the brain and significantly decline IRS-2. This resistance was accompanied by obvious memory loss, Aβ deposition, and tau phosphorylation, further visible diminishing in neurotransmitters such as dopamine and acetylcholine. Furthermore, oxidative stress was increased due to the antioxidant system being compromised. Interestingly, the pancreas injury and peripheral insulin resistance coexisted with brain insulin resistance. Indeed, the antidiabetic metformin was able to enhance all these drastic effects. In conclusion, brain insulin resistance could lead to AD and vice versa. These are highly linked syndromes that could influence peripheral organs. Further studies are required to stabilize this putative pathobiology relationship between them.

Long-term effects of warm water immersion on kidney tissue damage in diabetic rats

Objectives

This study aimed to investigate the effects of Warm Water Immersion (WWI) on inflammation, kidney function, and kidney tissue damage in rats with diabetes mellitus (DM).

Materials and Methods

Forty male rats were divided into four groups: Healthy Control (HC), Diabetic Control (DC), Diabetic Rats treated with WWI (DW), and Healthy Rats treated with WWI (HW). Daily 15-minute WWI sessions at 43 °C were administered for eight weeks. Various parameters including lipids, fasting blood sugar (FBS), HbA1C, insulin, advanced glycation end products (AGEs), HSP70, glomerular filtration rate (GFR), urinary albumin excretion, creatinine, blood urea nitrogen (BUN), oxidative stress, anti-oxidant parameters, and gene expression of RAGE, VEGF, and TGFß1 were assessed. Histological examination of kidney tissue was also conducted.

Results

Significant reductions in FBS, AGEs, glutathione, superoxide dismutase (SOD), and nitric oxide (NO) levels were observed in the DW group compared to DC. Expression of RAGE, VEGF, and TGFß1 genes decreased in DW. Triglycerides, total cholesterol, and LDL cholesterol were lower in DW. Insulin, HDL cholesterol, catalase, total anti-oxidant capacity (TAC), and tissue HSP70 were higher in DW. Histological assessment revealed reduced kidney damage in DW compared to DC.

Conclusion

WWI for eight weeks shows promise in mitigating diabetic nephropathy in rats, suggesting its potential as a non-invasive adjunctive therapy for managing diabetes complications.

Toxicological Assessment and Anti-diabetic Effects of Combined Extract of Chirata, Fenugreek and Sesame on Regulating TNF-α, TGF-β and Oxidative Stress in Streptozotocin Induced Diabetic Rats

BACKGROUND

Swertia chirayita, Trigonella foenum-gracum and Sesamum indicum are used as traditional medicines to treat diabetes mellitus. A collection of metabolic illnesses known as diabetes mellitus (DM) involves chronic hyperglycemia caused by flaws in insulin secretion, function, or both. Innate immunity and inflammation both play important roles in the etiology of diabetes- related microvascular problems.

OBJECTIVE

This study aims to examine the anti-diabetic effects and the acute toxicity of combined extract (1:1:1) of Swertia chirayita, Trigonella foenum-gracum and Sesamum indicum. To address the demand for higher effectiveness and safety, the current effort aims to construct anti-diabetic preparations containing methanolic extract from herbal medications.

METHODS

The OECD 423 method was used to investigate acute toxicity in rats. Rats were used as test subjects, and rats were given a 35 mg/kg BW injection of streptozotocin to develop diabetes. The diabetic control group was given Glibenclamide 0.25 mg/kg BW, while the experimental group's diabetic rats received 125 mg/kg BW and 250 mg/kg BW of a combined methanolic extract of all plants. Among the measurements looked at were acute oral toxicity, behavioral changes, body weight, serum glucose levels, lipid profiles, oxidative stress, renal function tests, and inflammatory mediators. All the rat groups' histopathologies of the kidney, liver, and stomach were compared. The data were evaluated using analysis of variance, and a post hoc test was then carried out.

RESULTS

The combined extracts' medium lethal doses (LD50) were higher than 2000 mg/kg, indicating that they are not poisonous under the conditions that can be observed. Streptozotocin-induced diabetic rats' elevated blood glucose was found to be considerably lower (p 0.01) in the treated group of rats. In the treated group of rats, it was discovered that the damage and disarray in the cells typical of Streptozotocin-induced DM had been repaired. The treated group of rats returned to normal levels of the lipid profile, hyperglycemia, decreased serum protein and liver glycogen, increased liver function, and kidney function markers seen in the rats of the DM control group.

CONCLUSION

The evaluated combined methanolic extract can be considered safe for use in rats. Combining methanolic extract from all selected medicinal plants (Swertia chirayita, Trigonella foenum-gracum and Sesamum indicum) has a potential anti-diabetic effect and can be safely developed as an alternative medicine.

Hypoglycemia and anxiolysis mediated by levofloxacin treatment in diabetic rats

Purpose

The present study was designed to determine the effect of levofloxacin (LVX) treatment on the blood glucose level, insulin sensitivity, anxiety level, nitrite and MDA level of STZ induced diabetic rats.

Methods

Wistar rats were used in the present study. The rats were made diabetic by the administration of single dose of STZ (45 mg/kg, i.p.) and NAD (50 mg/kg, i.p.). The rats with the blood glucose level greater than 200 mg/dl were considered as diabetic (confirmed at day-3 of STZ-NAD administration). The non-diabetic rats were considered as control and received saline.Diabetic rats received metformin (50 mg/kg, p.o.) and LVX (20, 25, 30 and 35 mg/kg, i.p.) daily for 14 days (starting from the day at which STZ was injected). Following administration on 14th day,the blood sample was collected and the rats were subjected to behavioral assays for the determination of locomotor activity and anxiety level. Plasma was separated and used for the estimation ofnitrite and malondialdehyde (MDA)level. On 15th day OGTT was performed in the overnight fasted rats for the assessment of insulin sensitivity.

Results

The results obtained suggested that the administration of STZ-NAD induced the hyperglycemia at day-3 of administration. Diabetic rats displayed the significant increase in blood glucose, anxiety related behavior, MDA level while significant decrease in the insulin sensitivity and plasma nitrite level. Daily administration of metformin to the diabetic rats decreased the blood glucose level, increased the time spent at the center of open field, reversed the anxiety related behavior in LDT and EPM, did not affect the plasma nitrite level, decreased the plasma MDA level, decreased the fasting glucose level and AUC in OGTT assay. LVX (30 and 35 mg/kg) treatment significantly decreased the blood glucose level of diabetic rats. LVX (20, 25 and 30 mg/kg) treatment significantly decreased the number of square crossing while LVX (20, 25, 30 and 35) treatment significantly increased the time spent at the center of the field by the diabetic rats. LVX (20 and 35 mg/kg) treatment significantly reversed the STZ induced anxiety in LDT while LVX (20, 30 and 35 mg/kg) treatment significantly reversed the STZ induced anxiety in EPM test. LVX (20, 25 and 35 mg/kg) treatment significantly increased the plasma nitrite level and LVX (20-35 mg/kg) treatment significantly decreased the MDA level of diabetic rats. Further only LVX (35 mg/kg) treatment significantly decreased the fasting glucose level and increased the AUC of diabetic rats.

Conclusion

In conclusion, STZ-NAD administration increased the blood glucose level, anxiety related behavior, decreased the plasma nitrite and increased the MDA level. LVX administration potentiated the diabetogenic effects of STZ-NAD in rats. Daily administration of LVX decreased the blood glucose level of diabetic rats. LVX administration alleviated the STZ induced anxiety in OFT, LDT and EPM test. LVX administration increased the plasma nitrite level and decreased the lipid peroxidation in diabetic rats.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01234-0.

Roflumilast ameliorates diabetic nephropathy in rats through down-regulation of JAK/STAT signaling pathway

Roflumilast is a potent selective inhibitor of the phosphodiesterase-4 enzyme which greatly manifest an anti-inflammatory activity in chronic obstructive pulmonary patients. Inflammation is a prominent factor in the prevalence of diabetic nephropathy, one of the most prevalent microvascular complications of Diabetes Mellitus. The present study was undertaken to assess the potential role of roflumilast in diabetic nephropathy. The model was developed by feeding a high-fat diet for four weeks and following streptozotocin (30 mg/kg) injection intraperitoneally. The rats with > 13.8 mmol/L blood glucose were treated with roflumilast (0.25, 0.5, 1 mg/kg) and standard metformin (100 mg/kg) orally once a day for eight weeks. Roflumilast (1 mg/kg) remarkably improved renal damage, indicated by an increase in 16% albumin, a decrease in 5% serum creatinine, 12% BUN, 19% HbA1c, and 34% blood glucose. It also significantly improves the oxidative stress levels, which was indicated by a decrease in 18% MDA level and an increase in GSH, SOD, and catalase by 6%, 4%, and 5%, respectively. In addition, Roflumilast (1 mg/kg) decreased the HOMA-IR index by 28% and increased the pancreatic β-cells functioning by 30%. Moreover, significant improvement in histopathological abnormalities were observed in roflumilast treatment groups. Roflumilast treatment was shown to down-regulate the gene expressions of TNF-α (2.1-fold), NF-kB (2.3-fold), MCP-1 (2.5-fold), fibronectin (2.7-fold), collagen IV (2.7-fold), STAT 1(1.06-fold), and STAT 3 (1.20-fold) and upregulated the expression of the Nrf2 (1.43-fold) gene. Roflumilast manifested a potential role in diabetic nephropathy as a renoprotective agent. Roflumilast effectively down-regulates the JAK/STAT pathway and restores renal functions.

DPP-4i versus SGLT2i as modulators of PHD3/HIF-2α pathway in the diabetic kidney

RATIONALE

Renal hypoxia is one of the currently highlighted pathophysiologic mechanisms of diabetic nephropathy (DN). Both hypoxia-inducible factor-1α (HIF-1α) and HIF-2α are major regulators of renal adaptive responses to hypoxia.

OBJECTIVES

This study aims to compare the effects of vildagliptin (a dipeptidyl peptidase-IV inhibitor, DPP-4i) and empagliflozin (a sodium-glucose cotransporter 2 inhibitor, SGLT2i) on the differential expression of renal HIF-1α/2α. Tissue expression of prolylhydroxylase 3 (PHD3), a key regulator of HIF-2α stability, was also highlighted in a diabetic nephropathy rat model. Type 1 diabetes mellitus was induced and diabetic rats were treated with either Vildagliptin or Empagliflozin (10 mg/kg/d each) for 12 weeks. Improvements in the kidney functional and histopathological parameters were addressed and correlated to changes in the renal expression of HIF-1α/2α, and PHD3. Urinary KIM-1 concentration was tested as a correlate to HIF pathway changes.

FINDINGS

Both vildagliptin- and empagliflozin-treated groups exhibited significant improvement in the functional, pathological, and ultra-structural renal changes induced by chronic diabetes. Compared to the untreated group, renal gene expression of HIF-1α was decreased while that of HIF-2α was increased in both treated groups, with significantly greater effects observed with SGLT2i. Renal PHD3 immune-reactivity was also decreased by both drugs, again with better efficacy for the SGLT2i. Importantly, improvements in the diabetic kidney biochemical and structural biomarkers were significantly correlated to PHD3 reductions and HIF-2α increments.

CONCLUSIONS

Both DPP-4i and SGLT2i could delay the progression of DN through their differential modulating effects on the PHD3/ HIF-2α pathway with significantly better efficacy for SGLT2i.

Short-Chain Fatty-Acid-Producing Micro-Organisms Regulate the Pancreatic FFA2-Akt/PI3K Signaling Pathway in a Diabetic Rat Model Affected by Pumpkin Oligosaccharides

Herein, we applied the Illumina MiSeq pyrosequencing platform to amplify the V3-V4 hypervariable regions of the 16 S rRNA gene of the gut microbiota (GM) and a gas chromatograph-mass spectrometer to detect the metabolites after supplementation with pumpkin oligosaccharides (POSs) to determine the metabolic markers and mechanisms in rats with type 2 diabetes (T2D). The POSs alleviated glucolipid metabolism by decreasing the serum low-density lipoprotein (LDL), total cholesterol (TC), and glucose levels. These responses were supported by a shift in the gut microbiota, especially in the butyric-acid-producing communities. Meanwhile, elevated total short-chain fatty acid (SCFA), isovaleric acid, and butyric acid levels were observed after supplementation with POSs. Additionally, this work demonstrated that supplementation with POSs could reduce TNF-α and IL-6 secretion via the FFA2-Akt/PI3K pathway in the pancreas. These results suggested that POSs alleviated T2D by changing the SCFA-producing gut microbiota and SCFA receptor pathways.

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.

Rodent models to study type 1 and type 2 diabetes induced human diabetic nephropathy

INTRODUCTION

Diabetic nephropathy (DN), an outcome of prolonged diabetes, has affected millions of people worldwide and every year the incidence and prevalence increase substantially. The symptoms may start with mild manifestations of the disease such as increased albuminuria, serum creatinine levels, thickening of glomerular basement membrane, expansion of mesangial matrix to severe pathological symptoms such as glomerular lesions and tubulointerstitial fibrosis which may further proceed to cardiovascular dysfunction or end-stage renal disease.

PERSPECTIVE

Numerous therapeutic interventions are being explored for the management of DN, however, these interventions do not completely halt the progression of this disease and hence animal models are being explored to identify critical genetic and molecular parameters which could help in tackling the disease. Rodent models which mostly include mice and rats are commonly used experimental animals which provide a wide range of advantages in understanding the onset and progression of disease in humans and also their response to a wide range of interventions helps in the development of effective therapeutics. Rodent models of type 1 and type 2 diabetes induced DN have been developed utilizing different platforms and interventions during the last few decades some of which mimic various stages of diabetes ranging from early to later stages. However, a rodent model which replicates all the features of human DN is still lacking. This review tries to evaluate the rodent models that are currently available and understand their features and limitations which may help in further development of more robust models of human DN.

CONCLUSION

Using these rodent models can help to understand different aspects of human DN although further research is required to develop more robust models utilizing diverse genetic platforms which may, in turn, assist in developing effective interventions to target the disease at different levels.

A sulfonamide chalcone AMPK activator ameliorates hyperglycemia and diabetic nephropathy in db/db mice

Diabetic nephropathy (DN) is a serious complication of diabetes mellitus (DM), which currently lacks effective treatments. AMP-activated protein kinase (AMPK) stimulation by chalcones, a class of polyphenols abundantly found in plants, is proposed as a promising therapeutic approach for DM. This study aimed to identify novel chalcone derivatives with improved AMPK-stimulating activity in human podocytes and evaluate their mechanisms of action as well as in vivo efficacy in a mouse model of DN. Among 133 chalcone derivatives tested, the sulfonamide chalcone derivative IP-004 was identified as the most potent AMPK activator in human podocytes. Western blot analyses, intracellular calcium measurements and molecular docking simulation indicated that IP-004 activated AMPK by mechanisms involving direct binding at allosteric site of calcium-dependent protein kinase kinase β (CaMKKβ) without affecting intracellular calcium levels. Interestingly, eight weeks of intraperitoneal administration of IP-004 (20 mg/kg/day) significantly decreased fasting blood glucose level, activated AMPK in the livers, muscles and glomeruli, and ameliorated albuminuria in db/db type II diabetic mice. Collectively, this study identifies a novel chalcone derivative capable of activating AMPK in vitro and in vivo and exhibiting efficacy against hyperglycemia and DN in mice. Further development of AMPK activators based on chalcone derivatives may provide an effective treatment of DN.

Ameliorative effects of Orlistat and metformin either alone or in combination on liver functions, structure, immunoreactivity and antioxidant enzymes in experimentally induced obesity in male rats

Background

Prevalence of obesity is increasing worldwide. Obesity is associated with incidences of metabolic disorders and cardiovascular diseases and the risk of having it rose sharply during the COVID-19 pandemic. Obesity is associated with oxidative stress, inflammatory markers and hepatic disorders and has become one of the silent killer diseases affecting global health.

Methods

This study examined the effects of obesity on liver functions (ALT, AST and LDH), lipid profile (TG, TC, HDL-c, LDL-c and vLDL-c), tumour necrosis factor alpha (TNF-α), inflammatory marker, C-reactive protein (CRP), leptin hormone and antioxidant enzymes (CAT, SOD and GPx) and lipid peroxidation marker (MDA) in liver homogenates besides histological structure of the liver tissues and assessment of DNA damage. Fifty male Wistar rats were used and they were divided into five treatment groups: I-Control group, II-high-fat diet (HFD) treated group (Obesity) group, III-HFD plus Orlistat (ORL), IV-HFD plus metformin (Met) and V- HFD plus ORL plus Met.

Results

Experimentally-induced obesity caused a significant increase in liver enzymes including lipid markers (triglycerides and total cholesterol), inflammatory markers, tumour markers and lipid peroxidation markers and a concurrent decline in antioxidant enzymes and damage of liver main structures characterised by presence of congestion and accumulation of mononuclear inflammatory cells in blood sinusoids. In contrast, groups treated with either ORL or Met or both group, we recorded restoration of normal hepatic structures and a decline in DNA damage, liver enzymes and antioxidant levels. The best restoration and amelioration were observed in the group treated with a combination of ORL and Met.

Conclusion

Our findings indicated the synergistic effect of ORL and Met in ameliorating hepatic functions and lipid profile, alleviating inflammation, genotoxicity and side effects of experimentally-induced obesity.

Possible mitigating effect of adropin on lung injury in diabetic rats: Targeting the role of Rho A/Rho-associated kinase pathway

This study evaluated possible mitigating effect of adropin on lung injury in diabetic rats, targeting role of Rho A/Rho-associated kinase pathway. Rats were allocated into four groups: control, adropin, diabetic, and diabetic+adropin groups. At the termination of the experiment, serum fasting glucose, insulin and adropin levels and insulin resistance were calculated. Wet/dry ratio, histopathological, immunohistochemical analyses, and relative real time gene expression of lung tissue was determined. Interleukin-6, tumor necrosis factor alpha, malondialdehyde, 8-Oxo-2'-deoxyguanosine, reduced glutathione, superoxide dismutase, Bcl-2, BAX, myeloperoxidase, intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and transforming growth factor-β were determined in lung tissue. Adropin treatment in diabetic rats notably attenuated hyperglycemia and insulin resistance. Also, it mitigated diabetic lung injury via suppressing effect on Rho A/ROCK pathway, apoptosis, inflammatory reactions, oxidative stress, and fibrosis of lung tissue. Adropin can be considered as a promising therapeutic agent for treating diabetic lung injury.

Pharmacological management of youth with type 2 diabetes and diabetic kidney disease: a comprehensive review of current treatments and future directions

INTRODUCTION

Diabetic kidney disease (DKD) is a leading cause of mortality in people with type 2 diabetes (T2D), and over 50% of individuals with youth-onset T2D will develop DKD as a young adult. Diagnosis of early-onset DKD remains a challenge in young persons with T2D secondary to a lack of available biomarkers for early DKD, while the injuries may still be reversible. Furthermore, multiple barriers exist to initiate timely prevention and treatment strategies for DKD, including a lack of Food and Drug Administration approval of medications in pediatrics; provider comfort with medication prescription, titration, and monitoring; and medication adherence.

AREAS COVERED

Therapies that have promise for slowing DKD progression in youth with T2D include metformin, renin-angiotensin-aldosterone system inhibitors, glucagon-like peptide-1 receptor agonists, sodium glucose co-transporter 2 inhibitors, thiazolidinediones, sulfonylureas, endothelin receptor agonists, and mineralocorticoid antagonists. Novel agents are also in development to act synergistically on the kidneys with the aforementioned medications. We comprehensively review the available pharmacologic strategies for DKD in youth-onset T2D including mechanisms of action, potential adverse effects, and kidney-specific effects, with an emphasis on published pediatric and adult trials.

EXPERT OPINION

Large clinical trials evaluating pharmacologic interventions targeting the treatment of DKD in youth-onset T2D are strongly needed.

Metformin and Canagliflozin Are Equally Renoprotective in Diabetic Kidney Disease but Have No Synergistic Effect

Diabetic Kidney Disease (DKD) is a major microvascular complication for diabetic patients and is the most common cause of chronic kidney disease (CKD) and end-stage renal disease. Antidiabetic drugs, such as metformin and canagliflozin, have been shown to exert renoprotective effects. Additionally, quercetin recently showed promising results for the treatment of DKD. However, the molecular pathways through which these drugs exert their renoprotective effects remain partly unknown. The current study compares the renoprotective potential of metformin, canagliflozin, metformin + canagliflozin, and quercetin in a preclinical rat model of DKD. By combining streptozotocin (STZ) and nicotinamide (NAD) with daily oral N(ω)-Nitro-L-Arginine Methyl Ester (L-NAME) administration, DKD was induced in male Wistar Rats. After two weeks, rats were assigned to five treatment groups, receiving vehicle, metformin, canagliflozin, metformin + canagliflozin, or quercetin for a period of 12 weeks by daily oral gavage. Non-diabetic vehicle-treated control rats were also included in this study. All rats in which diabetes was induced developed hyperglycemia, hyperfiltration, proteinuria, hypertension, renal tubular injury and interstitial fibrosis, confirming DKD. Metformin and canagliflozin, alone or together, exerted similar renoprotective actions and similar reductions in tubular injury and collagen accumulation. Renoprotective actions of canagliflozin correlated with reduced hyperglycemia, while metformin was able to exert these effects even in the absence of proper glycemic control. Gene expression revealed that the renoprotective pathways may be traced back to the NF-κB pathway. No protective effect was seen with quercetin. In this experimental model of DKD, metformin and canagliflozin were able to protect the kidney against DKD progression, albeit in a non-synergistic way. These renoprotective effects may be attributable to the inhibition of the NF-κB pathway.

NQO1 alleviates renal fibrosis by inhibiting the TLR4/NF-κB and TGF-β/Smad signaling pathways in diabetic nephropathy

OBJECTIVE

Diabetic nephropathy (DN) is one of the main complications of diabetes, and inflammation and fibrosis play an important role in its progression. NAD(P)H: quinone oxidoreductase 1 (NQO1) protects cells from oxidative stress and damage caused by toxic quinones. In the present study, we aimed to investigate the protective effects of NQO1 against diabetes-induced renal inflammation and fibrosis and the underlying mechanisms.

METHODS

In vivo, the kidneys of type 2 diabetes model db/db mice were infected with adeno-associated virus vectors to induce NQO1 overexpression. In vitro, human renal tubular epithelial (HK-2) cells transfected with NQO1 pcDNA3.1(+) were cultured under high-glucose (HG) conditions. Gene and protein expression was assessed by quantitative real-time PCR, Western blotting, immunofluorescence, and immunohistochemical staining. Mitochondrial reactive oxygen species (ROS) were detected with MitoSOX Red.

RESULT

Our study revealed that the expression of NQO1 was markedly downregulated and that Toll-like receptor (TLR)4 and TGF-β1 expression was upregulated in vivo and in vitro under diabetic conditions. Overexpression of NQO1 suppressed proinflammatory cytokine (IL-6, TNF-α, MCP-1) secretion, extracellular matrix (ECM) (collagen IV, fibronectin) accumulation and epithelial-mesenchymal transition (EMT) (α-SMA, E-cadherin) in the db/db mouse kidneys and HG-cultured HK-2 cells. Furthermore, NQO1 overexpression ameliorated HG-induced TLR4/NF-κB and TGF-β/Smad pathways activation. Mechanistic studies demonstrated that a TLR4 inhibitor (TAK-242) suppressed the TLR4/NF-κB signaling pathway, proinflammatory cytokine secretion, EMT and ECM-related protein expression in HG-exposed HK-2 cells. In addition, we found that the antioxidants N-acetylcysteine (NAC) and tempol increased the expression of NQO1 and decreased the expression of TLR4, TGF-β1, Nox1, and Nox4 and ROS production in HK-2 cells cultured under HG conditions.

CONCLUSIONS

These data suggest that NQO1 alleviates diabetes-induced renal inflammation and fibrosis by regulating the TLR4/NF-κB and TGF-β/Smad signaling pathways.

Is metformin neuroprotective against diabetes mellitus-induced neurodegeneration? An updated graphical review of molecular basis

Diabetes mellitus (DM) is a metabolic disease that activates several molecular pathways involved in neurodegenerative disorders. Metformin, an anti-hyperglycemic drug used for treating DM, has the potential to exert a significant neuroprotective role against the detrimental effects of DM. This review discusses recent clinical and laboratory studies investigating the neuroprotective properties of metformin against DM-induced neurodegeneration and the roles of various molecular pathways, including mitochondrial dysfunction, oxidative stress, inflammation, apoptosis, and its related cascades. A literature search was conducted from January 2000 to December 2022 using multiple databases including Web of Science, Wiley, Springer, PubMed, Elsevier Science Direct, Google Scholar, the Core Collection, Scopus, and the Cochrane Library to collect and evaluate peer-reviewed literature regarding the neuroprotective role of metformin against DM-induced neurodegenerative events. The literature search supports the conclusion that metformin is neuroprotective against DM-induced neuronal cell degeneration in both peripheral and central nervous systems, and this effect is likely mediated via modulation of oxidative stress, inflammation, and cell death pathways.

Exogenous glutamine ameliorates diabetic nephropathy in a rat model of type 2 diabetes mellitus through its antioxidant and anti-inflammatory activities

This study aimed to evaluate the effects of glutamine (Gln) on diabetic nephropathy and other complications in a rat model of type 2 diabetes mellitus. Streptozotocin/nicotinamide induced diabetic rats were enrolled as an animal model of type 2 diabetes mellitus. Animals were divided into control, diabetic, and Gln (1000 mg/l in drinking water, eight weeks) treated diabetic groups. Gln alleviated renal inflammatory and oxidative stress biomarkers (tumour necrosis factor-alpha, interleukin 6, glutathione peroxidase, total superoxide dismutase, and glutathione), decreased serum uric acid and creatinine, and restored renal histopathological changes (glomerular volume, sclerosis, and leukocyte infiltration). Additionally, Gln ameliorated other complications, including systemic oxidative stress (serum malondialdehyde and nitric oxide, serum and liver glutathione, glutathione peroxidase, and total superoxide dismutase, and liver catalase), insulin resistance, hyperglycaemia, and hyperlipidaemia. Collectively, Gln attenuates diabetic nephropathy and other complications in type 2 diabetes mellitus in rats through its antioxidant and anti-inflammatory activities.

Intestinal microbiome diversity of diabetic and non-diabetic kidney disease: Current status and future perspective

A significant portion of the health burden of diabetic kidney disease (DKD) is caused by both type 1 and type 2 diabetes which leads to morbidity and mortality globally. It is one of the most common diabetic complications characterized by loss of renal function with high prevalence, often leading to acute kidney disease (AKD). Inflammation triggered by gut microbiota is commonly associated with the development of DKD. Interactions between the gut microbiota and the host are correlated in maintaining metabolic and inflammatory homeostasis. However, the fundamental processes through which the gut microbiota affects the onset and progression of DKD are mainly unknown. In this narrative review, we summarised the potential role of the gut microbiome, their pathogenicity between diabetic and non-diabetic kidney disease (NDKD), and their impact on host immunity. A well-established association has already been seen between gut microbiota, diabetes and kidney disease. The gut-kidney interrelationship is confirmed by mounting evidence linking gut dysbiosis to DKD, however, it is still unclear what is the real cause of gut dysbiosis, the development of DKD, and its progression. In addition, we also try to distinguish novel biomarkers for early detection of DKD and the possible therapies that can be used to regulate the gut microbiota and improve the host immune response. This early detection and new therapies will help clinicians for better management of the disease and help improve patient outcomes.

Metformin: new applications for an old drug

Metformin is a biguanide, evolved as one of the most widely used medicines. The applications of this component include but are not limited to reducing blood glucose, weight loss, and polycystic ovary syndrome. Studies about other probable indications have emerged, indicating that this agent can also be utilized for other purposes. In this review, applications of metformin are noticed based on the current evidence. Metformin commonly is used as an off-label drug in non-alcoholic fatty liver disease (NAFLD), but it worsens inflammation and should not be used for this purpose, according to the latest research. Metformin decreased the risk of death in patients with liver cirrhosis. It is an effective agent in the prevention and improvement of survival in patients suffering hepatocellular carcinoma. There is evidence of the beneficial effects of metformin in colorectal cancer, early-stage prostate cancer, breast cancer, urothelial cancer, blood cancer, melanoma, and bone cancer, suggesting metformin as a potent anti-tumor agent. Metformin shows neuroprotective effects and provides a potential therapeutic benefit for mild cognitive impairment and Alzheimer's disease (AD). It also has been shown to improve mental function and reduce the incidence of dementia. Another condition that metformin has been shown to slow the progression of is Duchenne muscular dystrophy. Regarding infectious diseases, tuberculosis (TB) and coronavirus disease (COVID-19) are among the conditions suggested to be affected by metformin. The beneficial effects of metformin in cardiovascular diseases were also reported in the literature. Concerning renal function, studies showed that daily oral administration of metformin could ameliorate kidney fibrosis and normalize kidney structure and function. This study reviewed the clinical and preclinical evidence about the possible benefits of metformin based on recent studies. Numerous questions like whether these probable indications of metformin can be observed in non-diabetics, need to be described by future basic experiments and clinical studies.

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.

Exploring the Epigenetic Regulated Modulation of Fibroblast Growth Factor 21 Involvement in High-Fat Diet Associated Parkinson's Disease in Rats

Imbalance in brain glucose metabolism and epigenetic modulation during the disease course of insulin resistance (IR) associated with Parkinson's disease (PD) risk remains a prime concern. Fibroblast growth factor 21 (FGF21), the metabolic hormone, improves insulin sensitivity and elicits anti-diabetic properties. Chronic stress during brain IR may modulate the FGF21 expression and its dynamic release via epigenetic modifications. Metformin regulates and increases the expression of FGF21 which can be modulating in obesity, diabetes, and IR. Hence, this study was designed to investigate the FGF21 expression modulation via an epigenetic mechanism in PD and whether metformin (MF), an autophagy activator, and sodium butyrate (NaB), a pan histone deacetylase inhibitor, alone and in combination, exert any therapeutic benefit in PD pathology exacerbated by high-fat diet (HFD). Our results portray that the combination treatment with MF and NaB potentially attenuated the abnormal lipid profile and increased motor performance for the rats fed with HFD for 8 weeks followed by intrastriatal 6-hydroxy dopamine administration. The enzyme-linked immunosorbent assay (ELISA) estimations of C-reactive protein, tumor necrosis factor-α, interleukin-1 beta and 6, and FGF21 exhibited extensive downregulation after treatment with the combination. Lastly, mRNA, western blot, histological, and cresyl violet staining depicted that the combination treatment can restore degenerated neuronal density and increase the protein level compared to the disease group. The findings from the study effectively conclude that the epigenetic mechanism involved in FGF21 mediated functional abnormalities in IR-linked PD pathology. Hence, combined treatment with MF and NaB may prove to be a novel combination in ameliorating IR-associated PD in rats, probably via the upregulation of FGF21 expression.

The Effects of Metformin Treatment on Diabetic Albino Rats' Pancreas, Liver, and Kidney Histology

Metformin, an oral hypoglycemic drug, has traditionally been considered the standard therapy for hyperglycemia. Metformin's several modes of action include inhibition of hepatic gluconeogenesis, anti-glucagon activity, and insulin-sensitizing effect. This study aims to assess the effectiveness of Metformin on the liver, pancreatic, and kidney tissues of alloxan-induced diabetic albino rats. Twenty mature albino white male rats were allocated at random into two groups. Intraperitoneal injections of alloxan monohydrate were utilised to induce diabetic Mellitus type II in the first ten rats. The second group of rats were injected intraperitoneally with normal saline. Both groups were then separated into four subgroups: Group 1 consisted of non-diabetic rats that were only administered distilled water (control), Group 2 consisted of non-diabetic rats that were administered metformin at a dose of 1000 mg/kg/day, and Group 3 consisted of diabetic control animals that were administered alloxan intravenously and distilled water orally, but were not given any medications. After seven days of DM induction, diabetic rats were administered Metformin at a dose of 1000 mg/kg/day orally. After one month of therapy, the animals were slaughtered and their organs were harvested. Compared to the control group, the histological results of pancreatic tissue were normal in the treatment groups. In contrast, liver and kidney sections from non-diabetic control, non-diabetic, and diabetic animals given 1000 mg/kg/day of Metformin had normal histology. Still, both tissues of untreated diabetic control mice exhibited lymphocyte infiltration. Metformin has been found to have significant blood glucose lowering properties and the capacity to protect several organs from the negative consequences of diabetes.

Agomelatine improves streptozotocin-induced diabetic nephropathy through melatonin receptors/SIRT1 signaling pathway

INTRODUCTION

Diabetic nephropathy (DN) is a major cause of end-stage renal disease (ESRD). Agomelatine, a melatonin receptor agonist, has a potent anti-inflammatory activity. The current study aimed to determine the ameliorative anti-inflammatory effect of agomelatine against DN.

METHODS

We used 10 % fructose with streptozotocin (STZ) to induce DN in male Wistar rats. Diabetic rats were treated with agomelatine in presence or absence of melatonin receptor antagonist (luzindole) or Sirtuin1 (SIRT1) inhibitor (EX527). SIRT1 expression was measured by qRT-PCR and immunohistochemical analysis. The expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), 5'adenosine monophosphate-activated protein kinase (AMPK), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion protein-1 (VCAM-1), and monocyte chemoattractant protein-1 (MCP-1) were measured using ELISA. Histological assessment was performed using hematoxylin and eosin-stained renal sections.

RESULTS

Fructose and STZ treatment induced diabetes, insulin resistance, and renal damage accompanied by reduced SIRT1 expression, increased NFκB activation, and decreased AMPK phosphorylation in the kidney. Agomelatine treatment improved kidney histology and function and upregulated SIRT1 expression (2-fold). Inhibition of melatonin receptors and SIRT1 activity increased NFκB phosphorylation (2.13 and 1.98-folds, respectively), reduced AMPK activation (0.51 and 0.53-folds, respectively), increased inflammatory markers ICAM-1 (2.16 and 2.23-folds, respectively), VCAM-1 (2.19 and 2.26-folds, respectively), and MCP-1(2.84 and 3.12-folds, respectively), and inhibited the ameliorative effect of agomelatine on kidney structure and function.

CONCLUSION

Our findings reveal the ameliorative anti-inflammatory activity of agomelatine against STZ-induced DN and this effect is SIRT1- and melatonin receptor-dependent. Therefore, agomelatine may be beneficial to prevent the development of ESRD from diabetes mellitus.

Coadministration of L-alanine and L-glutamine ameliorate blood glucose levels, biochemical indices and histological features in alloxan-induced diabetic rats

We evaluated the effects of supplementation of L-alanine and L-glutamine on blood glucose levels and biochemical parameters in alloxan-induced diabetic rat. Forty-nine animals were distributed into seven equal groups. Except for the non-diabetic control, diabetes was induced in all groups by intravenous alloxan injection followed by daily supplementation with amino acids for 14 days. Weight and blood glucose were monitored during supplementation, while biochemical parameters such as liver and renal functions, lipid profile, and antioxidant markers were evaluated post-intervention. A significant increase (p < .05) in weight and decrease in blood glucose were observed in the amino acid(s) treated groups. The supplementation with both amino acids restored important tissue antioxidants, liver and kidney functions and rescued islets cells degeneration. Histopathological examinations of important tissues showed the restoration of alloxan-induced physiopathological changes by the amino acids. Thus, these amino acids might serve as nutraceuticals for the management and treatment of diabetes. PRACTICAL APPLICATIONS: The discovery and production of antidiabetic bioactive compounds are often challenging, and the existing antidiabetic drugs are expensive. Amino acids are key regulators of glucose metabolism, insulin secretion, and insulin sensitivity; thus, they can play a crucial role in alleviating diabetes. Here, we present findings that strongly suggest the potential of pure amino acids (L-alanine and L-glutamine) for the management and treatment of diabetes. We show that these amino acids, when supplemented singly or coadministered can lower blood glucose levels and restore several other biochemical parameters implicated in diabetes. Hence, these cheap amino acids may be consumed as nutraceuticals or food supplements by diabetics for the treatment/management of diabetes. Foods rich in these amino acids may also be consumed as part of the diet of diabetic patients.

Reno-protective effects of GLP-1 receptor agonist and anti-platelets in experimentally induced diabetic kidney disease in male albino rats

Objectives

The prevalence of chronic kidney disease in diabetics is progressively increasing with an increased risk of fatal complications.

Materials and Methods

Sixty male albino rats were used in the study, and type 2 diabetes mellitus were induced. Diabetic rats were divided randomly into 5 groups, the control diabetic group and 4 treated groups were treated with metformin (group3), dulaglutide (group 4), metformin & cilostazol (group 5), and the last group was treated with dulaglutide & cilostazol (group 6). At the end of the experiment, the weight of rats and systolic blood pressure were estimated. After overnight fasting, the serum levels of blood glucose, lipid profile, and kidney function were measured. After scarification, gene expression of eNOS and NFKB in kidney tissue were estimated and kidney tissues were examined for histopathology.

Results

Diabetic rats showed a significant increase in body weight, blood pressure, serum blood glucose, lipid profile, and impaired kidney function. Metformin and dulaglutide are associated with a significant decrease in blood pressure, blood glucose level, serum lipid profile, and improved kidney function. These changes are associated with a significant increase in anti-oxidative markers, and decreased inflammatory and fibrotic markers, especially with the addition of cilostazol.

Conclusion

Metformin and dulaglutide have been shown to ameliorate kidney damage in diabetics by stimulating the anti-oxidant defense system, normalizing kidney functional parameters, and improving histopathological changes. The addition of cilostazol to metformin or dulaglutide increased some of their anti-oxidants and anti-inflammatory properties.

Vitamin D and Swimming Exercise Prevent Obesity in Rats under a High-Fat Diet via Targeting FATP4 and TLR4 in the Liver and Adipose Tissue

The prevalence of obesity has risen in the last decades, and it has caused massive health burdens on people's health, especially metabolic and cardiovascular issues. The risk of vitamin D insufficiency is increased by obesity, because adipose tissue alters both the requirements for and bioavailability of vitamin D. Exercise training is acknowledged as having a significant and long-term influence on body weight control; the favorable impact of exercise on obesity and obesity-related co-morbidities has been demonstrated via various mechanisms. The current work illustrated the effects of vitamin D supplementation and exercise on obesity induced by a high-fat diet (HFD) and hepatic steatosis in rats and explored how fatty acid transport protein-4 (FATP4) and Toll-like receptor-4 antibodies (TLR4) might be contributing factors to obesity and related hepatic steatosis. Thirty male albino rats were divided into five groups: group 1 was fed a normal-fat diet, group 2 was fed an HFD, group 3 was fed an HFD and given vitamin D supplementation, group 4 was fed an HFD and kept on exercise, and group 5 was fed an HFD, given vitamin D, and kept on exercise. The serum lipid profile adipokines, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) were analyzed, and the pathological changes in adipose and liver tissues were examined. In addition, the messenger-ribonucleic acid (mRNA) expression of FATP4 and immunohistochemical expression of TLR4 in adipose and liver tissues were evaluated. Vitamin D supplementation and exercise improved HFD-induced weight gain and attenuated hepatic steatosis, along with improving the serum lipid profile, degree of inflammation, and serum adipokine levels. The expression of FATP4 and TLR4 in both adipose tissue and the liver was downregulated; it was noteworthy that the group that received vitamin D and was kept on exercise showed also improvement in the histopathological picture of this group. According to the findings of this research, the protective effect of vitamin D and exercise against obesity and HFD-induced hepatic steatosis is associated with the downregulation of FATP4 and TLR4, as well as a reduction in inflammation.

Investigation of the Chemical Composition, Antihyperglycemic and Antilipidemic Effects of Bassia eriophora and Its Derived Constituent, Umbelliferone on High-Fat Diet and Streptozotocin-Induced Diabetic Rats

This study was designed to investigate the chemical profile, antihyperglycemic and antilipidemic effect of total methanolic extract (TME) of Bassia eriophora and isolated pure compound umbelliferone (UFN) in high-fat diet (HFD)- and streptozotocin (STZ)- induced diabetic rats. TME was subjected to various techniques of chromatography to yield UFN. Diabetes was induced after eight weeks of HFD by administration of STZ (40 mg/kg) intraperitoneally, and experimental subjects were divided into five groups. The diabetic control showed an increase in levels of blood glucose throughout the experiment. Treatments were initiated in the other four groups with glibenclamide (GLB) (6 mg/kg), TME (200 mg/kg and 400 mg/kg) and isolated UFN (50 mg/kg) orally. The effect on blood glucose, lipid profile and histology of the pancreatic and adipose tissues was assessed. Both 200 and 400 mg/kg of TME produced a comparably significant decrease in blood glucose levels and an increase in insulin levels with GLB. UFN began to show a better blood sugar-lowering effect after 14 days of treatment, comparatively. However, both 400 mg/kg TME and UFN significantly returned blood glucose levels in diabetic rats compared to normal rats. Analysis of the lipid profile showed that while HFD + STZ increased all lipid profile parameters, TME administration produced a significant decrease in their levels. Histopathological examinations showed that treatment with TME and UFN revealed an improved cellular architecture, with the healthy islets of Langerhans and compact glandular cells for pancreatic cells distinct from damaged cells in non-treated groups. Conversely, the adipose tissue displayed apparently normal polygonal fat cells. Therefore, these results suggest that TME has the potential to ameliorate hyperglycemia conditions and control lipid profiles in HFD + STZ-induced diabetic rats.

Recent Progress in the Diagnosis and Management of Type 2 Diabetes Mellitus in the Era of COVID-19 and Single Cell Multi-Omics Technologies

Type 2 diabetes mellitus (T2DM) is one of the world's leading causes of death and life-threatening conditions. Therefore, we review the complex vicious circle of causes responsible for T2DM and risk factors such as the western diet, obesity, genetic predisposition, environmental factors, and SARS-CoV-2 infection. The prevalence and economic burden of T2DM on societal and healthcare systems are dissected. Recent progress on the diagnosis and clinical management of T2DM, including both non-pharmacological and latest pharmacological treatment regimens, are summarized. The treatment of T2DM is becoming more complex as new medications are approved. This review is focused on the non-insulin treatments of T2DM to reach optimal therapy beyond glycemic management. We review experimental and clinical findings of SARS-CoV-2 risks that are attributable to T2DM patients. Finally, we shed light on the recent single-cell-based technologies and multi-omics approaches that have reached breakthroughs in the understanding of the pathomechanism of T2DM.

A Glimpse of Inflammation and Anti-Inflammation Therapy in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common complication of diabetes mellitus and a major cause of end-stage kidney disease (ESKD). The pathogenesis of DKD is very complex and not completely understood. Recently, accumulated evidence from in vitro and in vivo studies has demonstrated that inflammation plays an important role in the pathogenesis and the development of DKD. It has been well known that a variety of pro-inflammatory cytokines and related signaling pathways are involved in the procession of DKD. Additionally, some anti-hyperglycemic agents and mineralocorticoid receptor antagonists (MRAs) that are effective in alleviating the progression of DKD have anti-inflammatory properties, which might have beneficial effects on delaying the progression of DKD. However, there is currently a lack of systematic overviews. In this review, we focus on the novel pro-inflammatory signaling pathways in the development of DKD, including the nuclear factor kappa B (NF-κB) signaling pathway, toll-like receptors (TLRs) and myeloid differentiation primary response 88 (TLRs/MyD88) signaling pathway, adenosine 5′-monophosphate-activated protein kinase (AMPK) signaling pathways, inflammasome activation, mitochondrial DNA (mtDNA) release as well as hypoxia-inducible factor-1(HIF-1) signaling pathway. We also discuss the related anti-inflammation mechanisms of metformin, finerenone, sodium-dependent glucose transporters 2 (SGLT2) inhibitors, Dipeptidyl peptidase-4 (DPP-4) inhibitors, Glucagon-like peptide-1 (GLP-1) receptor agonist and traditional Chinese medicines (TCM).

Therapeutic Potential of MgO and MnO Nanoparticles Within the Context of Thyroid Profile and Pancreatic Histology in a Diabetic Rat Model

Magnesium oxide (MgO) and manganese oxide (MnO) have been reported to be effective against Diabetes Mellitus (DM). However, their nanoparticulate form has not been evaluated for antidiabetic effect. MgO and MnO nanoparticles (15–35 nm) were synthesized and subsequently characterized by ultraviolet-visible spectroscopy (UV-VIS), zeta sizer, and scanning electron microscopy. 6–7 weeks old rats weighing 200–220 mg were divided into 07 equal groups (n = 8), namely, negative control (NC), positive control (PC), standard control (Std-C), MgO high dose group (MgO-300) and low dose group (MgO-150), and MnO nanoparticle high dose (MnO-30) and low dose group (MnO-15). Diabetes was chemically induced (streptozotocin 60 mg/kg B.W) in all groups except the NC. Animals were given CMD and water was ad libitum. Nanoparticles were supplemented for 30 days after the successful induction of diabetes. Blood and tissue samples were collected after the 30^th day of the trial. The mean serum glucose, insulin, and glucagon levels were improved maximally in the MgO-300 group followed by MgO-150 and MnO-30 groups. Whereas the MnO-15 group fails to show any substantial improvement in the levels of glucose, insulin, and glucagon as compared to the positive control group. Interesting the serum triiodothyronine, thyroxine, and thyroid-stimulating hormone levels were markedly improved in all the nanoparticle treatment groups and were found to be similar to the standard control group. These results highlight the modulatory properties of MgO and MnO nanoparticles and merit further studies delineating the molecular mechanisms through which these nanoparticles induce antidiabetic effects.

Optimization of germination and ultrasonic-assisted extraction for the enhancement of γ-aminobutyric acid in pumpkin seed

Germination and ultrasonic-assisted extraction (UAE) are economical and effective methods to enhance bioactive compounds in plant seeds. We optimized the germination parameters and UAE parameters by using response surface methodology to maximize the recovery of γ-aminobutyric acid (GABA) in pumpkin seeds. The optimal germination conditions were as follows: soaking the seeds at 28°C for 6 h with 0.2% CaCl2, 3.8 mg/ml monosodium glutamate, and 4.0 mg/ml vitamin B6, then germination at 30°C for 61.6 h. The optimal conditions for UAE were as follows: 1:75 (w/v) material-to-solvent ratio, 220 W ultrasonic power, and ultrasonic treatment at 50°C for 14.4 min, which afforded an extraction yield of 2679 ± 10 mg/100 g. Moreover, the GABA-enhanced extract showed the potential of hypolipidemic effect in type 2 diabetes rats. These results confirmed that a combination of germination and UAE increased the GABA yield from pumpkin seeds and provided a basis for GABA-enhanced production to improve lifestyle-associated diseases.

Potential of honey against the onset of autoimmune diabetes and its associated nephropathy, pancreatitis, and retinopathy in type 1 diabetic animal model

Honey has been used as a traditional remedy for various health benefits. This study investigated the potential of honey against the onset of autoimmune diabetes and its associated secondary complications in type 1 diabetic (T1D) experimental animals. Autoimmune diabetes was induced in Sprague Dawley rats, and at the same time, the rats were treated with honey or metformin. Sandwich ELISAs were used to estimate blood glucose, hemoglobin A1C (HbA1c), total cholesterol, and triglycerides. Histopathological examinations determined the T1D-induced lesions on kidneys, pancreas, cornea, and retina. Treatment of rats with honey during the course of T1D induction showed a significant reduction in fasting-blood-glucose and HbA1c (p < 0.01), and total lipid profile was also improved (p < 0.05). Not only these, but honey also reduced the T1D-induced lesions in the kidney, pancreas, and cornea/retina (p < 0.05). Metformin showed similar effects and was used as a positive control. In conclusion, honey showed therapeutic potential against the onset of autoimmune diabetes, as it reduces blood glucose/HbA1c and improves the lipid profile by reducing the plasma levels of total cholesterol, low-density lipoproteins (LDL), very low-density lipoprotein (VLDL), and triglycerides. Moreover, it also showed protective potential against the development of diabetic nephropathy, pancreatitis, and retinopathy.

Metformin for Cardiovascular Protection, Inflammatory Bowel Disease, Osteoporosis, Periodontitis, Polycystic Ovarian Syndrome, Neurodegeneration, Cancer, Inflammation and Senescence: What Is Next?

Diabetes is accompanied by several complications. Higher prevalence of cancers, cardiovascular diseases, chronic kidney disease (CKD), obesity, osteoporosis, and neurodegenerative diseases has been reported among patients with diabetes. Metformin is the oldest oral antidiabetic drug and can improve coexisting complications of diabetes. Clinical trials and observational studies uncovered that metformin can remarkably prevent or alleviate cardiovascular diseases, obesity, polycystic ovarian syndrome (PCOS), osteoporosis, cancer, periodontitis, neuronal damage and neurodegenerative diseases, inflammation, inflammatory bowel disease (IBD), tuberculosis, and COVID-19. In addition, metformin has been proposed as an antiaging agent. Numerous mechanisms were shown to be involved in the protective effects of metformin. Metformin activates the LKB1/AMPK pathway to interact with several intracellular signaling pathways and molecular mechanisms. The drug modifies the biologic function of NF-κB, PI3K/AKT/mTOR, SIRT1/PGC-1α, NLRP3, ERK, P38 MAPK, Wnt/β-catenin, Nrf2, JNK, and other major molecules in the intracellular signaling network. It also regulates the expression of noncoding RNAs. Thereby, metformin can regulate metabolism, growth, proliferation, inflammation, tumorigenesis, and senescence. Additionally, metformin modulates immune response, autophagy, mitophagy, endoplasmic reticulum (ER) stress, and apoptosis and exerts epigenetic effects. Furthermore, metformin protects against oxidative stress and genomic instability, preserves telomere length, and prevents stem cell exhaustion. In this review, the protective effects of metformin on each disease will be discussed using the results of recent meta-analyses, clinical trials, and observational studies. Thereafter, it will be meticulously explained how metformin reprograms intracellular signaling pathways and alters molecular and cellular interactions to modify the clinical presentations of several diseases.

Sex-specific effects of metformin and liraglutide on renal pathology and expression of connexin 45 and pannexin 1 following long-term high-fat high-sugar diet

The comparative effects of the two commonly used antidiabetic drugs metformin and liraglutide on renal pathology and expression of connexin 45 (Cx45) and pannexin 1 (Panx1) in adult obese rats fed high-fat high-sugar diet (HFHSD) were studied. Considering recent data on the profound influence of sex on metformin and liraglutide effects, we compared the effects of both drugs between male and female animals. 44-week-old Sprague-Dawley rats were separated into 4 groups that were fed: standard diet, HFHSD, HFHSD treated with metformin (s.c., 50 mg/kg/day) and HFHSD treated with liraglutide (s.c., 0.3 mg/kg/day). Treatment with metformin or liraglutide lasted for 14 weeks. Histology and immunohistochemistry were performed to quantify renal pathological changes and Cx45 and Panx1 expression. HFHSD caused thickening of the Bowman's capsule (BC). Both metformin and liraglutide failed to ameliorate the BC thickening; metformin even worsened it. Effects on the tubulointerstitial fibrosis score, BC thickness and Cx45 and Panx1 expression were sex-dependent. We found a 50% increase in mitochondria in proximal tubules of metformin- and liraglutide-treated HFHSD-fed rats, but these effects were not dependent on the sex. This is a first study showing that the effects of metformin and liraglutide on kidney pathology in rats fed HFHSD are mostly sex-dependent and that these effects are not necessarily beneficial. Both drugs changed the Cx45 and Panx 1 expression; hence their effects could be related to amelioration of disruptions in intercellular communication.

Effect of silymarin and metformin on the sperm parameters and histopathological changes of testes in diabetic rats: An experimental study

BACKGROUND

Oxidative stress is a major contributor to diabetes, which can lead to testicular damage and infertility.

OBJECTIVE

This study aimed to compare the effects of metformin as a chemical drug with silymarin as an herbal agent on the sperm parameters and histopathological changes of testes in diabetic rats.

MATERIALS AND METHODS

Thirty-two male Wistar rats (250-270 gr) were randomly divided into four groups: 1) control; 2) diabetic; 3) diabetic+metformin 200 mg/kg; and 4) diabetic+silymarin 100 mg/kg. Daily injections were administered intraperitoneally for 56 days. At the end of the treatment, blood sampling was performed for biochemical assessment. Then, the rats were sacrificed and their left testis and epididymis were cut for sperm analysis as well as histopathology and morphometric evaluation.

RESULTS

Diabetes was associated with a reduced sperm count, motility, viability, maturity, and chromatin quality of sperm (p ≤ 0.001). It was also associated with a higher malondialdehide level and lower total antioxidant capacity level of serum in comparison with the control group (p ≤ 0.001). There was a significant difference in the seminiferous tubule diameter, germinal epithelium height, and testicular histopathological alterations in the diabetic rats compared with the control rats (p ≤ 0.001). Treatment with metformin and silymarin improved the above-mentioned parameters and this improvement was more substantial in silymarin-treated animals (p ≤ 0.001).

CONCLUSION

In diabetic rats, metformin and silymarin improved sperm parameters, sperm DNA integrity, seminiferous tubule diameter, germinal epithelium thickness, and testicular histopathological complications; this improvement was more substantial in the silymarin-treated group. So, the findings of this study suggest that silymarin is more effective than metformin in treating diabetic-induced infertility.

Potential Interaction of Fresh Garlic with Metformin during Ischemia-Reperfusion Induced Cardiac Injury in Diabetic Rats

Methods

The study was undertaken on both normoglycemic and alloxan (90 mg/kg) induced diabetic Sprague Dawley rats weighing 150–250 g. At the completion of the treatment phase (30 days for garlic, 250 mg/kg, oral; 10 days for MET, 70 mg/kg, oral), rats were anesthetized and mounted on the modified Langendorff's apparatus. IRI was produced by myocardial no-flow global ischemia. Developed tension (DT) and heart rate (HR) were recorded both before and after ischemia. The perfusate was collected to estimate the leakage of cardiac biomarkers (Creatine Kinase-MB: CK-MB and Lactate dehydrogenase: LDH). Hearts were removed from the setup and utilized to prepare heart tissue homogenate (HTH) and histological slides. The endogenous antioxidants, superoxide dismutase (SOD) and catalase (CAT), in addition to oxidative thiobarbituric acid substances (TBS), were estimated in HTH.

Results

The hemodynamic parameters, including percentage recovery in HR and DT, were found significantly higher in animals pretreated with garlic and MET in diabetic rats (DR). Both SOD and CAT enzyme activities increased significantly while TBS levels were reduced in the HTH of animals treated with garlic and MET. The cardiac markers CK-MB and LDH levels also increased in HTH with a corresponding decrease in the perfusate. The histopathological changes in the heart and pancreas demonstrated noticeable protection of the tissues due to pretreatment with garlic and MET. Taken together, these findings advocate that reactive oxygen species derived from hyperglycemia execute an important function in myocardial global IRI; the therapy of garlic homogenate was found to be effective in alleviating these toxic effects.

Conclusion

The combined therapy of MET and garlic provided synergistic cardioprotection, implying that garlic seems to possess promise in lowering toxic parameters by protecting diabetic induced myocardial injury.