Acute and sub-acute toxicity study of ethanol extract from Nectandra leucantha Nees & Mart. (Lauraceae) barks.

Nectandra leucantha has been used in traditional medicine. Several metabolites isolated from N. leucantha extracts displayed immunomodulatory, antileishmanial properties, but the determination of the toxicological profile in mammals has not previously been performed. In this study, the ethanol extract from N. leucantha barks (EENl) was characterized by HPLC/HRESIMS. To study acute toxicity, female mice received EENl in a single dose of 100, 300, 1000, or 2000 mg/kg bw. Later, sub-acute toxicity was introduced in female and male mice by oral gavage at 100, 500 or 1000 mg/kg bw for 28 consecutive days. Hematological and biochemical profiles from the blood as well as histological analysis from the liver and kidney were performed. The HPLC/HRESIMS analysis of the EENl revealed the presence of six neolignans chemically related to dehydrodieugenol B. In the oral acute and sub-chronic studies, EENl did not produce in all doses evaluated any alteration in behavior, biochemical, hematological, body weight gain and food intake or sudden death in Swiss mice. In addition, histopathological data did not reveal any disturbance in liver and kidney morphology after 28 days of EENl treatment. Our results indicate that EENl at dosage levels up to 2000 mg/kg bw is non-toxic and can be considered safe for mammals.

Hexane fraction from Brazilian Morus nigra leaves improved oral carbohydrate tolerance and inhibits α-amylase and α-glucosidase activities in diabetic mice.

Morus nigra, popularly known as mulberry, has been traditionally used as anti-diabetic herbal medication. This study focused on hexane fraction from Brazilian M. nigra leaves (Hex-Mn) effects on digestion and absorption of carbohydrate in diabetic mice. The high-performance liquid chromatography (HPLC) analysis was performed, and showed the presence of flavonoids isoquercetin and kaempferol-3-O-rhamnoside. Hex-Mn did not alter oral glucose tolerance test; however, it prevented hyperglycemia in oral sucrose and starch tolerance test in diabetic mice. Also, Hex-Mn was more efficient to inhibit the α-glucosidase, showing lower inhibitory effect on α-amylase activity in vitro. The results suggest that Hex-Mn may delay the carbohydrate digestion, but not glucose transport through brush border membrane of the intestine, which contribute with reduction in postprandial hyperglycemia in mice. Hex-Mn has antihyperglycemic effect by attenuating the carbohydrate digestion in diabetic mice, which could be explained, at least in part, by the presence of isoquercetin and kaempferol-3-O-rhamnoside.

Brazilian Morus nigra Attenuated Hyperglycemia, Dyslipidemia, and Prooxidant Status in Alloxan-Induced Diabetic Rats.

Morus nigra has been used popularly for several proposes, including diabetic. In an attempt to support medicinal value, the acute hypoglycemic, hypolipidemic, and antioxidant effects of the ethanolic extract of Morus nigra (EEMn 200 or 400 mg/kg b.w.) were evaluated in normal and alloxan-induced diabetic treated for 14 days. Serum biochemical and antioxidant analysis were performed at the end of experiment. Oral glucose tolerance test was performed at 10th and 15th days. Chromatographic analysis by HPLC-DAD of EEMn was performed. Insulin was used as positive control to glycemic metabolism as well as fenofibrate to lipid metabolism. EEMn (400 mg/kg/day) reduced fasting and postprandial glycaemia, improved oral glucose tolerance, and reduced lipolysis and proteolysis in diabetic rats. EEMn decreased the blood levels of total cholesterol and increased HDL level when compared to the diabetic control rats. At higher levels, EEMn reduced triglycerides and VLDL levels in diabetic rats. Also, EEMn reduced malondialdehyde and increased the reduced glutathione levels in liver of diabetic rats. Chromatographic analysis identified the presence of the flavonoids rutin, isoquercetin, and kaempferitrin. Acute EEMn treatment reduced hyperglycemia, improved oral glucose tolerance, and minimized dyslipidemia and oxidative stress leading to a reduction in atherogenic index in alloxan-induced diabetic rats.

Safflower (Catharmus tinctorius L.) oil supplementation in overnourished rats during early neonatal development: effects on heart and liver function in the adult.

Carthamus tinctorius L. (common name: safflower) is an herb whose extracted oil (safflower oil) has been employed in both alternative and conventional medicine in the treatment of disease. Overnutrition during early postnatal life can increase the lifetime risk of obesity and metabolic syndrome. Here we investigate the effect of safflower oil supplementation given during a critical early developmental stage on the eventual occurrence of metabolic disease in overnourished rats. Groups of overnourished or adequately nourished rats were randomly assigned into 2 additional groups for supplementation with either safflower oil (SF) or vehicle for 7 to 30 days. Murinometric data and weights were examined. Serum was collected for measurement of glucose, cholesterol, high-density lipoprotein cholesterol, and triglycerides. Heart and liver oxidative status were also measured. Overnutrition for 7-30 days induced a significant increase in body weight and in values for abdominal circumference, thoracic circumference, body length, and body mass index. SF supplementation did not attenuate the effect of overnutrition on any of these parameters. In addition, overnutrition increased levels of glucose, triglycerides, and very low-density lipid compared with normal controls, but SF supplementation had no effect on these parameters. Measures of oxidative status in heart or liver were not influenced by overnutrition. However, oxidative measures were altered by SF supplementation in both of these organs. The present study reveals that nutritional manipulation during early development induces detrimental effects on metabolism in the adult that are not ameliorated by supplemental SF.