Histopathological study of the combination of metformin and garlic juice for the attenuation of gentamicin renal toxicity in rats

Combined effect of metformin and gallic acid on inflammation, antioxidant status, endoplasmic reticulum (ER) stress and glucose metabolism in fructose-fed streptozotocin-induced diabetic rats

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Metformin, gallic acid and a combination of both improved glucose metabolism and antioxidant status in diabetic rats.

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Metformin, gallic acid and a combination of both lowered levels of IL-6 and TNF-α in liver and pancreas of diabetic rats.

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Metformin, gallic acid and a combination of both decreased the expression of ATF4 in liver and pancreas of diabetic rats.

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Metformin/GA combination appeared more effective than metformin only and gallic acid only.

Over time, diabetes patients usually need combination therapy involving two or more agents, including phytonutrients to attain therapeutic targets. The purpose of this research is to elucidate the combined effect of metformin and gallic acid (GA) on glucose metabolism, inflammation as well as oxidative and endoplasmic reticulum (ER) stresses in fructose-fed diabetic rats. Thirty-five rats of Wistar strain were arbitrarily distributed into five groups, each containing seven animals as follows: normal control, diabetic control, groups administered 100 mg/kg bw metformin only, 50 mg/kg bw gallic acid only and a combination of both. Experimental animals were made diabetic by single injection of 40 mg/kg streptozotocin (intraperitoneally) subsequent to 14 days administration of 10 % fructose prior. Treatment of rats continued for 21 days following diabetes confirmation. Glucose and insulin levels as well as lipid profile were evaluated in the serum, while activities of catalase and superoxide dismutase were estimated in both liver and pancreas. In addition, levels of malondialdehyde, interleukin-6 and tumor necrosis factor-alpha, as well as expression of activating transcription factor-4 were evaluated in liver and pancreas of diabetic rats. Activities of glucose-6-phosphatase and glucokinase were also determined in liver of diabetic animals. Metformin only, GA only and combination of metformin and GA significantly improved antioxidant status and glucose homeostasis while inflammation and endoplasmic reticulum stress were significantly ameliorated in diabetic rats. Metformin/GA combination appeared to improve glucose metabolism by increasing insulin level and ameliorating the dysregulated activities of glucose metabolizing enzymes and ER stress better than either metformin only or GA only. It could be concluded that coadministration of metformin/GA produced a combined effect in ameliorating diabetes in Wistar rats and could be considered in treatment of diabetes.

Effect of hydroalcoholic Allium atroviolaceum L. on the pathology of testicular tissue in cyclophosphamide-treated mice

Background

The most important side effects of Cyclophosphamide, as an anticancer broad-spectrum drug, are the negative effects on the reproduction and fertility because of oxidative stress. Considering the antioxidant properties of medicinal plants, especially those of the Allium genus, this paper studied the effect of hydroalcoholic extract of Allium atroviolaceum L. on the pathology of testicular tissue in CP-treated mice.

Methods

Groups of this experimental study consisted of normal saline recipients; three groups receiving A. atroviolaceum extract at 50, 100, 200 mg/kg; three groups receiving A. atroviolaceum extract at 50, 100, and 200 mg/g and 6.6 mg/kg of Cyclophosphamide; and a group given Cyclophosphamide at 1.6 mg/kg. All injections were performed intra-peritoneally. After 30 days, the testicular histological profile as well as the number of spermatozoa, the number of primary and round spermatocytes, and the number of spermatogonia were investigated.

Results

Cyclophosphamide treatment significantly reduced the lumen diameter, the seminiferous tubule diameter, the epithelial thickness, as well as decreased the quantity of spermatozoa and round and primary spermatocytes compared to the control group. Cyclophosphamide groups treated with A. atroviolaceum extract at 50, 100 and 200 mg/kg in a significant manner improved these variables (P < 0.001).

Conclusion

A. atroviolaceum extract can significantly improve Cyclophosphamide-induced toxicity and pathological process on testicular tissue. It seems that this plant, with high antioxidant capacity, can be considered a complementary therapy for Cyclophosphamide to prevent undesirable effects on the reproductive system.

Diabetes mellitus and renal failure: Prevention and management

Nowadays, diabetes mellitus (DM) and hypertension are considered as the most common causes of end-stage renal disease (ESRD). In this paper, other than presenting the role of DM in ESRD, glucose metabolism and the management of hyperglycemia in these patients are reviewed. Although in several large studies there was no significant relationship found between tight glycemic control and the survival of ESRD patients, it is recommended that glycemic control be considered as the main therapeutic goal in the treatment of these patients to prevent damage to other organs. Glycemic control is perfect when fasting blood sugar is less than 140 mg/dL, 1-h postprandial blood glucose is less than 200 mg/dL, and glycosylated hemoglobin (HbA1c) is 6-7 in patients with type 1 diabetes and 7-8 in patients with type 2 diabetes. Administration of metformin should be avoided in chronic renal failure (CRF) because of lactic acidosis, the potentially fatal complication of metformin, but glipizide and repaglinide seem to be good choices.

Protection of renal tubular cells by antioxidants: current knowledge and new trends

Acute renal damage mainly develops following toxic or ischemic insults and is defined as acute. These damages have largely been attributed to oxidative stress. Recently much attention has been directed toward decreased renal tubular cell regeneration during tubular cell injury. Antioxidants have recently been the focus of researchers and scientists for prevention and treatment of various oxidative stress-related conditions, including renal toxicities. Although free radicals are known to contribute in kidney injury and abundant researches, particularly laboratory trials, have shown the beneficial effects of antioxidants against these complications, long term clinical trials do not uniformly confirm this matter, especially for single antioxidant consumption such as vitamin C. The aim of this paper is to discuss the possible explanation of this matter.

Atherosclerosis: process, indicators, risk factors and new hopes

Background:

Atherosclerosis is the major cause of morbidities and mortalities worldwide. In this study we aimed to review the mechanism of atherosclerosis and its risk factors, focusing on new findings in atherosclerosis markers and its risk factors. Furthermore, the role of antioxidants and medicinal herbs in atherosclerosis and endothelial damage has been discussed and a list of important medicinal plants effective in the treatment and prevention of hyperlipidemia and atherosclerosis is presented.

Methods:

The recently published papers about atherosclerosis pathogenesis and herbal medicines effective in the treatment and prevention of hyperlipidemia and atherosclerosis were searched.

Results:

Inflammation has a crucial role in pathogenesis of atherosclerosis. The disease is accompanied by excessive fibrosis of the intima, fatty plaques formation, proliferation of smooth muscle cells, and migration of a group of cells such as monocytes, T cells, and platelets which are formed in response to inflammation. The oxidation of low density lipoprotein (LDL) to Ox-LDL indicates the first step of atherosclerosis in cardiovascular diseases. Malondialdehyde factor shows the level of lipoperoxidation and is a sign of increased oxidative pressure and cardiovascular diseases. In special pathological conditions such as severe hypercholesterolemia, peroxynitrite concentration increases and atherosclerosis and vascular damage are intensified. Medicinal plants have shown to be capable of interacting these or other pathogenesis factors to prevent atherosclerosis.

Conclusions:

The pathogenesis factors involved in atherosclerosis have recently been cleared and the discovery of these factors has brought about new hopes for better prevention and treatment of atherosclerosis.

Metformin and diabetic kidney disease: a mini-review on recent findings

Metformin, an oral anti-diabetic agent in the biguanide class is a widely prescribed drug to treat high blood glucose in patients with type 2 diabetes mellitus. Metformin has three different roles, including blood glucose regulatory effect, protection of kidney tubular cell by acting as an effective antioxidant and finally ameliorative effect on diabetic kidney disease through saving the podocytes. Therefore, diabetic patients may benefit from all of these three distinct ameliorative effects.

Anethum graveolens and hyperlipidemia: A randomized clinical trial

BACKGROUND

It has been established that hyperlipidemia increases the incidence and mortality associated with coronary heart disease. In this study, the effects of Dill (Anethum graveolens) were evaluated on lipid profile of hypercholesterolemic patients.

MATERIALS AND METHODS

In this clinical study, 91 hyperlipidemic patients were randomly designated into two groups. One group received gemfibrozil (900 mg daily) and the other group received Dill tablet (six tablets daily) for 2 months. The blood lipids including total cholesterol, triglyceride and high density lipoprotein (HDL)-cholesterol from each group were assessed at the beginning and end of the trial.

RESULTS

Use of gemfibrozil brought about increased HDL-cholesterol by 3.91% (P < 0.05) and reduced triglyceride and total cholesterol by 32.7% (P < 0.05) and 9.41% (P < 0.05), respectively. Applying Dill tablet for 2 months resulted in reduction of total cholesterol up to 18% (P < 0.05) and triglyceride by 7.38% (P < 0.05). However, circulating HDL-cholesterol was not affected by this treatment. In this study, gemfibrozil decreased triglyceride and increased HDL-cholesterol more than anethum (P < 0.05). Anethum decreased total cholesterol more than gemfibrozil (P < 0.05). Patients treated with anethum did not report any side effects.

CONCLUSION

The results of this trial indicate that Dill might be beneficial for hypercholesterolemic and hypertriglycemic patients.

Metformin: Current knowledge

Diabetes mellitus is a group of metabolic disorders in which the blood glucose is higher than normal levels, due to insufficiency of insulin release or improper response of cells to insulin, resulting in high blood pressure. The resultant hyperglycemia produces sever complications. Metformin drug has been shown to prevent diabetes in people who are at high risk and decrease most of the diabetic complications. Recent reports on metformin, not only indicate some implications such as renoprotective properties have been suggested for metformin, but some reports indicate its adverse effects as well that are negligible when its benefits are brought into account. We aimed here to review the new implications of metformin and discuss about the concerns in the use of metformin, referring to the recently published papers.

A double blind clinical trial on the efficacy of honey drop in vernal keratoconjunctivitis

Purpose. This trial was designed to evaluate the efficacy and safety of topical honey eye drops in patients with diagnosed VKC. Methods. This clinical trial was conducted on 60 patients with diagnosed VKC. The patients were selected and randomly allocated between two groups of 30. Patients in two groups received honey eye drop (60% in artificial tear) or placebo, other than cromolyn and fluorometholone 1% eye drops, to be used topically in each eye, four times per day. The patients were examined with slit lamp and torch at baseline and the follow-up visits on the 1st, 3rd, and 6th months of the study for redness, limbal papillae, and intraocular pressure. Results. Out of 60 patients who completed the study, 19 patients (31.7%) were female. There was significant increase in eye pressure and reduction in redness as well as limbal papillae, following the consumption of the honey drop in honey group compared to placebo control group (P < 0.05). At the end of trial, one patient in honey group and 7 ones in placebo group had limbal papillae (P < 0.05). Conclusion. Topical honey eye drops, when used along with Cromolyn and Fluorometholone eye drops, might be beneficial for the treatment of VKC.

Oxidative stress and hypertension: Possibility of hypertension therapy with antioxidants

Hypertension is a major risk factor for myocardial infarction, heart failure, stroke, peripheral arterial disease, and aortic aneurysm, and is a cause of chronic kidney disease. Hypertension is often associated with metabolic abnormalities such as diabetes and dyslipidemia, and the rate of these diseases is increasing nowadays. Recently it has been hypothesized that oxidative stress is a key player in the pathogenesis of hypertension. A reduction in superoxide dismutase and glutathione peroxidase activity has been observed in newly diagnosed and untreated hypertensive subjects, which are inversely correlated with blood pressure. Hydrogen peroxide production is also higher in hypertensive subjects. Furthermore, hypertensive patients have higher lipid hydroperoxide production. Oxidative stress is also markedly increased in hypertensive patients with renovascular disease. If oxidative stress is indeed a cause of hypertension, then, antioxidants should have beneficial effects on hypertension control and reduction of oxidative damage should result in a reduction in blood pressure. Although dietary antioxidants may have beneficial effects on hypertension and cardiovascular risk factors, however, antioxidant supplementation has not been shown consistently to be effective and improvement is not usually seen in blood pressure after treatment with single or combination antioxidant therapy in subjects thought to be at high risk of cardiovascular disease. This matter is the main focus of this paper. A list of medicinal plants that have been reported to be effective in hypertension is also presented.

Effect of normobaric hyperoxia on gentamicin-induced nephrotoxicity in rats

OBJECTIVES

Gentamicin sulphate (GS) nephrotoxicity seems to be related to the generation of reactive oxygen species. There is evidence that oxygen preconditioning increases the activity of antioxidant enzymes.

MATERIALS AND METHODS

Forty eight female rats were divided into 6 groups (n=8) as follows: group 1 was the control, group 2 received daily GS, groups 3,4 and 5 received oxygen 2 hr/day for 2 days, 4 hr/day for 2 days, 4 hr/day for 4 days, recpectively and then received daily GS, group 6 received oxygen 2 hr/day for 2 days and then received 2 hr oxygen before daily GS injection. Oxygen (with 90% purity) used at the flow rate of 4 l/min. GS administred for 8 days (100 mg/kg, IP). Tissue sections prepared from the left kidney, stained with PAS method and then studied hisopathologically and stereologically. The right kidneys were homogenized and the supernatants were prepared. Serum MDA, creatinine and urea, renal MDA, gluthatione and catalase activity were measured. The data were analyzed by Mann-Whitney U test at the significant level of P<0.05.

RESULTS

Oxygen therapy significantly improves serum creatinine and urea, preserve tubular volume density, reduce tubular necrosis in groups 4 and 6 compared to group 2. Oxygen therapy significantly increases renal catalase in groups 4 and 6 compared to group 2.

CONCLUSION

Pretreatment with normobaric hyperoxia and daily oxygen therapy improved gentamicin nephrotoxicity possibly via inhibition of lipid peroxidation and increasing the renal catalase activity but could not restore any parameter at the same levels as control group.

Ameliorative effect of melatonin against contrast media induced renal tubular cell injury

BACKGROUND AND OBJECTIVE

Reactive oxygen species (ROS) is a mediator of renal damage. Melatonin is a potent-free radical scavenger. Our objective was to test whether melatonin would protect against the nephrotoxicity of contrast media.

METHODS

In an experimental study 40 adult male Wistar rats were randomly divided into four equal groups including: 1) Control group (No drug), 2) Contrast media group (10 ml/kg iodixanol i.v. single dose), 3) Contrast media and melatonin (first 10 ml/kg iodixanol then 10 ml/kg/day melatonin by i.p. injection on days 3, 4 and 5) and 4) Contrast media and melatonin pretreatment group (melatonin 10 ml/ kg/day by i.p. injection on 1, 2 and 3 days, then 10 ml/kg iodixanol by i.v. injection on third day. The blood creatinine and BUN as well as the histological changes were evaluated for severity of renal injury (degeneration, vacuolization of tubular renal cells, dilatation of tubular lumen and presence of debris in the lumens), by scoring from one to four.

RESULTS

Contrast media significantly increased the creatinine and BUN and renal injury (p<0.05). Melatonin prevented and reversed the injury induced by contrast media (P<0.05). Pretreatment with melatonin reduced the renal injury induced by contrast media (P<0.05).

CONCLUSION

Melatonin is an effective drug to prevent contrast-induced renal injury. Therefore its usage (especially pretreatment) might be beneficial in patients who are planning to use contrast media agents.