Chrysin mitigated obesity by regulating energy intake and expenditure in rats.

BACKGROUND AND AIM: Chrysin is a flavonoid found in plant extracts from Passiflora species, honey and propolis. It has demonstrated anti-adipogenic activity in vitro but there are no studies substantiating the anti-obesity activity of chrysin in vivo. EXPERIMENTAL PROCEDURE: The pancreatic lipase (PL) inhibitory potential of chrysin was determined by preliminary in silico screening and further confirmed by in vitro PL inhibitory assay and oral fat tolerance test (OFTT). The effect of chrysin on acute feed intake and sucrose preference test was determined in normal rats. Obesity was induced by feeding of high fructose diet (HFD) to the rats. The rats were divided into six groups: normal control, HFD control, orlistat and three doses of chrysin (25, 50 and 100 mg/kg body weight). Body weight, body mass index (BMI), abdominal circumference/thoracic circumference (AC/TC) ratio, calorie intake, adiposity index, fecal cholesterol, locomotor activity and histopathology of the adipose tissue of the rats were evaluated. RESULTS: Chrysin showed good affinity to PL with competitive type of inhibition. It significantly reduced serum triglycerides in OFTT. Chrysin also significantly reduced acute feed intake and sucrose preference in rats. Chrysin significantly decreased the body weight, BMI, AC/TC ratio, adiposity index, calorie intake while it significantly increased the fecal cholesterol and locomotor activity of the rats. Chrysin was found to reduce the size of the adipocytes when compared to the HFD control group. CONCLUSION: Thus, chrysin exerted anti-obesity effect by inhibiting PL, reducing sucrose preference, reducing calorie intake and increasing the locomotor activity of rats.

Punica granatum improves renal function in gentamicin-induced nephropathy in rats via attenuation of oxidative stress.

BACKGROUND: Gentamicin is widely used as an antibiotic for the treatment of gram negative infections. Evidences indicates that oxidative stress is involved in gentamicin-induced nephrotoxicity. In Ayurvedic medicine, Punica granatum Linn. is considered as 'a pharmacy unto itself". It has been claimed in traditional literature, to treat various kidney ailments due to its antioxidant potential. OBJECTIVE: To explore the possible mechanism of action of methanolic extract of P.granatum leaves (MPGL) in exerting a protective effect on gentamicin-induced nephropathy. MATERIAL AND METHODS: Animals were administered with gentamicin (80 mg/kg/day i.m.) and simultaneously with MPGL (100, 200 and 400 mg/kg p.o.) or metformin (100 mg/kg p.o.) for 8 days. A satellite group was employed in order to check for reversibility of nephrotoxic effects post discontinuation of gentamicin administration. At the end of the study, all the rats were sacrificed and serum-urine parameters were investigated. Antioxidant enzymes and tumor necrosis factor alpha (TNF-α) levels were determined in the kidney tissues along with histopathological examination of kidneys. RESULTS: Increase in serum creatinine, urea, TNF-α, lipid peroxidation along with fall in the antioxidant enzymes activity and degeneration of tubules, arterioles as revealed by histopathological examination confirmed the manifestation of nephrotoxicity caused due to gentamicin. Simultaneous administration of MPGL and gentamicin protected kidneys against nephrotoxic effects of gentamicin as evidenced from normalization of renal function parameters and amelioration of histopathological changes. CONCLUSION: Data suggests that MPGL attenuated oxidative stress associated renal injury by preserving antioxidant enzymes, reducing lipid peroxidation and inhibiting inflammatory mediators such as TNF-α.

Plumbagin reduces obesity and nonalcoholic fatty liver disease induced by fructose in rats through regulation of lipid metabolism, inflammation and oxidative stress.

BACKGROUND: Chronic consumption of fructose causes obesity and nonalcoholic fatty liver disease (NAFLD). Currently available therapies have limitations; hence there is a need to screen new molecules. Plumbagin is a naphthoquinone present in the roots of Plumbago species which has hypolipidemic and hepatoprotective activities. METHODS: Rats were divided into five groups: normal control, disease control, orlistat, plumbagin (0.5 mg/kg and 1 mg/kg body weight). The normal control group received standard diet and drinking water while the remaining groups received fructose in drinking water alongwith the standard diet for 16 weeks. Orlistat and plumbagin were administered orally from the 9th week-16th week. The body weight, calorie intake and weights of visceral adipose tissue and liver were determined. Blood glucose, insulin, lipid profile and liver function tests were determined. Antioxidant and inflammatory parameters, lipids and collagen were determined in the liver. Gene expression of SREBP-1c and PPAR-α were determined in the liver. The histopathology of the adipose tissue and liver were also studied. RESULTS: Fructose feeding resulted in a significant increase in the body weight gain, calorie intake, visceral fat, liver weight, blood glucose and insulin and caused dyslipidemia which was mitigated by plumbagin. Plumbagin exerted antioxidant, anti-inflammatory and anti-fibrotic effects in the liver and reduced the hepatic lipids. Plumbagin reduced the gene expression of SREBP-1c and increased that of PPAR-α. Plumbagin reduced the hypertrophy of adipocytes and ameliorated the degenerative changes in the liver. CONCLUSION: Plumbagin thus seems to be a promising molecule for the management of obesity and NAFLD.

Agmatine attenuates chronic unpredictable mild stress-induced anxiety, depression-like behaviours and cognitive impairment by modulating nitrergic signalling pathway.

Agmatine, a neurotransmitter/neuromodulator, has shown to exert numerous effects on the CNS. Chronic stress is a risk factor for development of depression, anxiety and deterioration of cognitive performance. Compelling evidences indicate an involvement of nitric oxide (NO) pathway in these disorders. Hence, investigation of the beneficial effects of agmatine on chronic unpredictable mild stress (CUMS)-induced depression, anxiety and cognitive performance with the involvement of nitrergic pathway was undertaken. Mice were subjected to a battery of stressors for 28days. Agmatine (20 and 40mg/kg, i.p.) alone and in combination with NO modulators like L-NAME (15mg/kg, i.p.) and l-arginine (400mg/kg i.p.) were administered daily. The results showed that 4-weeks CUMS produces significant depression and anxiety-like behaviour. Stressed mice have also shown a significant high serum corticosterone (CORT) and low BDNF level. Chronic treatment with agmatine produced significant antidepressant-like behaviour in forced swim test (FST) and sucrose preference test, whereas, anxiolytic-like behaviour in elevated plus maze (EPM) and open field test (OFT) with improved cognitive impairment in Morris water maze (MWM). Furthermore, agmatine administration reduced the levels of acetylcholinesterase and oxidative stress markers. In addition, agmatine treatment significantly increased the BDNF level and inhibited serum CORT level in stressed mice. Treatment with L-NAME (15mg/kg) potentiated the effect of agmatine whereas l-arginine abolished the anxiolytic, antidepressant and neuroprotective effects of agmatine. Agmatine showed marked effect on depression and anxiety-like behaviour in mice through nitrergic pathway, which may be related to modulation of oxidative-nitrergic stress, CORT and BDNF levels.