Antioxidant properties of Trifolium resupinatum and its therapeutic potential for Alzheimer's disease.

INTRODUCTION: Alzheimer's disease (AD) is the most common cause of dementia and is characterized by a progressive deterioration in cognitive function, which typically begins with impairment in memory. Persian clover (Trifolium resupinatum) is an annual plant found in central Asia. Due to its contents (high flavonoid and isoflavones), extensive researches have been done on its therapeutic properties, such as multiple sclerosis (MS) treatment. In this study, we investigate the neuroprotective effects of this plant on Streptozotocin (STZ)-induced AD in rats. MATERIAL AND METHODS: This research aimed to evaluate the neuroprotective effect of Trifolium resupinatum on the spatial learning and memory, superoxide dismutase (SOD), expressions of ß amyloid 1-42 (Ab 1-42 ), and b amyloid 1-40 (Ab 1-40 ) in the hippocampus of STZ-induced Alzheimer rats. RESULTS: Our data showed that Trifolium resupinatum extract administration for two weeks before and one week after AD induction significantly improves maze escape latency ( p = 0.027, 0.001 and 0.02 in 100, 200, and 300 mg of the extract, respectively) and maze retention time ( p = 0.003, 0.04 and 0.001 in 100, 200, and 300 mg of the extract, respectively). Also, the administration of this extract significantly increases the SOD levels from 1.72+0.20 to 2.31+0.45 ( p = 0.009), 2.48+0.32 ( p = 0.001) and 2.33+0.32 ( p = 0.007) and decreases the expressions of Ab 1-42 ) ( p = 0.001 in all concentrations of the extract) and Ab 1-40 ) ( p = 0.001 in all concentrations of the extract) in the rat's hippocampus. CONCLUSIONS: This study suggests that the alcoholic extract of Trifolium resupinatum has anti-Alzheimer and neuroprotective effects on rats.

Allium jesdianum hydro alcoholic extract ameliorates diabetic nephropathy by suppressing connective tissue growth factor (CTGF) and receptor for advanced glycation endproducts (RAGE) gene expression in diabetic rats with streptozotocin.

OBJECTIVES: Diabetic nephropathy is one of the major complications of diabetes, the use of medicinal plants is increasing due to fewer side effects. This study was designed to examine antidiabetic effects of Allium jesdianum (A. jesdianum) ethanolic extract and evaluate its effects on oxidative stress markers and the expression of connective tissue growth factor (CTGF) and receptor for advanced glycation endproducts (RAGE) genes in the kidney of type 1 diabetic rats. METHODS: In this study, we randomly divided 24 rats into four groups with six rats in each group as follows: Cnt group: normal control receiving normal saline, Dibt group: diabetic control receiving normal saline daily, Dibt + A. jesdianum 250 group: diabetic rats receiving A. jesdianum at a dose of 250 mg/kg bw daily, Dibt + A. jesdianum 500 group: diabetic rats receiving A. jesdianum at a dose of 500 mg/kg bw daily. To induce diabetes, we used 55 mg/kg bw dose of streptozotocin intraperitoneally. The concentration of fasting blood glucose (FBG) and serum urea, creatinine and albumin, SOD, MDA (using spectrophotometric methods) and gene expression of CTGF and RAGE in kidney tissue (using real-time PCR methods) were quantified in the diabetic rats that received A. jesdianum for 42 days, and were compared to control rats. RESULTS: The results showed that in the diabetic group the FBG and serum urea, creatinine and expression of kidney CTGF and RAGE genes and the levels of SOD and MDA significantly increased and serum albumin significantly decreased compared to the Cnt group (p<0.001). Administration of A. jesdianum significantly improved the FBG and serum urea, creatinine and albumin compared to Dibt group (p<0.05). It was shown the A. jesdianum significantly decrease the kidney expression levels of CTGF and RAGE genes and improve oxidative stress (increased SOD and decreased MDA) in the kidney tissues when compared to Dibt group (p<0.001). Also, it was found that the beneficial effects of the A. jesdianum were dose-dependent. CONCLUSIONS: The results of this study showed that administration of A. jesdianum for 42 days has beneficial anti-diabetic and anti-nephropathic effects in diabetic rats and can be used as an adjunct therapy in the treatment of diabetes.

Antidiabetic and protective effects of Scrophularia striata ethanolic extract on diabetic nephropathy via suppression of RAGE and S100A8 expression in kidney tissues of streptozotocin-induced diabetic rats.

Background The present study was conducted to examine the antidiabetic effects of Scrophularia striata ethanolic extract and to evaluate its effects on oxidative stress markers and RAGE and S100A8 gene expressions in the kidney of type 1 diabetic rats. Methods A total of 36 rats (weight 200-250 g) were randomly assigned into six groups as follows: Cnt, Cnt + S. striata 100, and Cnt + S. striata 200 that received normal saline, 100 mg/kg bw, and 200 mg/kg bw of ethanol extract of S. striata, respectively; and group Dibt, Dibt + S. striata 100, and Dibt + S. striata 200 that received normal saline, 100 mg/kg bw, and 200 mg/kg bw of ethanol extract of S. striata, respectively. Type 1 diabetes was induced in rats by a single injection of streptozotocin (55 mg/kg bw). After 60 days of treatment, biochemical factors and oxidative stress markers (superoxide dismutase [SOD] and malondialdehyde [MDA]) were measured using spectrophotometric methods. RAGE and S100A8 gene expressions were analyzed using real-time polymerase chain reaction. Results Diabetes significantly impairs serum and urine fasting blood glucose (FBG), lipid profile, creatinine, urea, and albumin parameters. After the treatment with S. striata extract, these parameters are close to the normal range. It was shown that the S. striata extract significantly decreased the kidney expression levels of RAGE and S100A8 genes and improved oxidative stress markers (SOD and MDA) in the kidney tissues when compared with the diabetic control group. It was also found that the beneficial effects of the S. striata were dose dependent. Conclusions The ethanolic extract of S. striata has beneficial antidiabetic effects. Moreover, by reducing RAGE and S100A8 gene expressions and by improving oxidative stress, S. striata might be used as adjuvant treatment for diabetic complications.