Aims: This work aimed to investigate the effects of Bauhinia monandra ethanolic extract (E) on blood glucose levels (G), insulin and lipids of control (C) and prenatal malnourished (M) rats. Samples: Animals (from 90 days) were on standard or isocaloric high glucose diet (67%, w/w) during 30 days.
Study Design: Animals received 0.1% DMSO (2.5 ml/kg, po.) or E (500 mg/kg, po.). Glucose tolerance was evaluated in blood following glucose overload (1.5 g/kg, po.).
Place and Duration of Study: Departamento de Bioquímica and Departamento de Fisiologia e Farmacologia, Universidade Federal de Pernambuco, between January 2006 and February 2007.
Methodology: In acute tests, glucose tolerance and serum insulin were evaluated in C and M receiving DMSO or E. Lipids and hepatic enzymes were analyzed before DMSO or E application. Glucose was orally administered by gavage, for glucose tolerance; thirty minutes later, E or DMSO was given. Blood samples were collected for glucose and insulin measurements. In the chronic assay, glucose tolerance, lipids and hepatic enzymes were studied in groups C or M receiving DMSO or E. The group M receiving E had a diet rich in glucose (30 days). Glucose tolerance, lipids, and hepatic enzymes were evaluated before and after diet rich in glucose treatment with E. Serum insulin was measured by chemiluminescence; also, aspartate and alanine aminotransferases were analyzed after high dietary glucose. Serum total cholesterol and triglycerides were estimated with an auto analyzer.
Results: In control rats, acute E administration reduced G, but did not change insulin secretion; in M rats, it induced insulin peak. In chronic study, animals on high glucose diet with E showed lower G; prenatal malnourished rats revealed higher insulin levels. Cholesterol, triglycerides and alanine aminotransferase did not change by intrauterine malnutrition or E.
Conclusion: Results indicated that E may act on beta-cells and stimulate insulin secretion.
The high cost of feed ingredients such as corn is one of the most important factors in livestock production. If agricultural by-products such as Vigna unguiculata husk could replace corn starch in animal feed, the cost of raising livestock would be cheaper. Some indices of carbohydrate metabolism in rats maintained on heat-treated Vigna unguiculata husk were investigated to ascertain the extent of carbohydrate metabolism in rats maintained on the husk. Forty-six weanling albino rats (31.11 g±3.32 g) were divided into seven groups of equal average weight. The groups were then assigned to seven experimental diets. The rats were fed on their respective experimental diets and water ad libitum. Blood pyruvate and lactate concentrations, glucose 6-phosphatase activities in selected tissues, and serum lipid profiles were determined. The results revealed that the concentrations of pytuvate (0.86 mg per 100 ml blood) and lactate (12.96 mg per 100 ml blood) in rats fed 50% inclusion level of 90-minute boiled husk were not significantly different (p =.05) from the respective values (0.85 mg per 100 ml blood and 12.53 mg per 100 ml blood) in rats fed the control diet. Also, 50% inclusion level of 90-minute boiled husk caused no significant changes in the lipid profiles. With the exception of rats maintained on the control diet, the liver (37.46 nmol/hr/mg Protein) and kidney (19.02 nmol/hr/mg Protein) concentrations of glucose 6-phosphatase activities in rats fed 50% inclusion level of 90-minute boiled husk were significantly lower (p = 0.05) than the concentrations in the liver and kidney of rats maintained on other diets. The findings show that diets based on 50% inclusion level of 90-minute boiled husk are well metabolized. Therefore, 50% replacement of corn starch by 90-minute boiled Vigna unguiculata pod husk may be considered as a way of reducing the cost of livestock production.
The modulatory effect of different concentrations of ethanol extract of matured leaves of M. esculenta, Crantz at 200, 600, 1000 and 1400 µg/ml was investigated in vitro on mitochondrial membrane permeability transition pore in liver, kidney and heart of diabetic animals in the absence and presence of 20 µM exogenous Ca2+. The extract at these concentrations had no significant (p< 0.05) effect on mitochondrial membrane permeability transition (MPT) pore of the three organs in the absence of Ca2+. However, in the presence of Ca2+, the extract exhibited significant (p< 0.05) inhibition of mitochondrial membrane transition pore opening: liver by 62.66%, 42.47%, 22.44% and 17.63% at 1400, 1000, 600, and 200 µg/ml, respectively. In the heart, inhibition of MMPT pore opening was by 92.86%, 71.43%, 64.29% and 57.14% at 200, 600, 1400, and 1000 µg/ml, respectively. In the kidney, the extract also inhibited mitochondrial membrane transition pore opening in a concentration-dependent manner by 92.65%, 91.18%, 89.71% and 72.06% at 1400, 1000, 600, and 200 µg/ml, respectively. Caspase-3 activity in vitro was also reduced with increasing extract concentrations; thus confirming that the extract inhibits MMPT pore opening in the presence of Ca2+. The extract may be able to protect these organs against damage, resulting from Ca2+ overload that may trigger cell death, and as such it may be useful in the management of diseases related to tissue wastage such as cardiomyopathy and nephropathy which are associated with Type 2 diabetes mellitus.
Background: Oxidative stress is involved in the developing of several diseases including diabetes followed by the majority of severe acute illness and/or contra complications. Current studies indicated increasing plasma viscosity with progressing microangiopathy among diabetic cases.
Objectives: To evaluate whether antioxidant nutrients biomarkers of selenium, vitamin A and vitamin E are associated with alterations of blood viscosity in pre-diabetes (PD).
Materials and Methods: Whole blood samples were collected from (20) PD non obese subjects with blood HbA c1 (5.7-6.4%) and (20) control healthy subjects. Different biomolecules were assessed including selenium concentration in both plasma and red blood cells (RBCs), glutathione peroxidase activity in RBCs, plasma lipids, vitamin A and vitamin E plasma concentration, and the blood viscosity.
Results: Comparing to control healthy subjects, blood viscosity was significantly increased, selenium was not altered in the plasma of PD, subjects but it was markedly decreased in RBCs and negative correlation with the elastic component of whole blood viscosity. Mean RBCs, glutathione activity was reduced. Vitamin A and vitamin E plasma levels were correlated with blood viscosity. Plasma viscosity correlated strongly with increased cholesterol level (r=0.67, P 0.002) and triglycerides concentration (r=0.66 , P 0.005).
Conclusion: Blood viscosity increased in PD and this may be contributed to reduced nutritional antioxidants.
Aims: To purify and characterize a novel chito-specific lectin from Benincasa hispida fruit.
Study Design: Protein purification and characterization using biochemical and biophysical techniques under various denaturing conditions.
Place and Duration of Study: Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, India, from July 2013 to Jan 2015.
Methodology:Benincasa hispida fruit was used as lectin source and purified using chitin affinity and gel filtration chromatographic techniques. The hemagglutinating activity was detected with rabbit erythrocytes. Conformational studies were carried out using steady-state fluorescence, Circular dichroism and FTIR spectroscopic methods.
Results: The protein exists as a homodimer of 34 kDa as determined using gel filtration chromatography and MALDI-TOF/TOF and the subunit was 17 kDa as estimated from SDS-PAGE. Circular dichroism spectroscopic studies showed that BhL has high content of β-sheets (40%). The fluorimetric titrations with chitobiose and chitotriose sugars yielded the association constants Ka as 1.2 x102 M-1 and 1x104 M-1 at 37ºC, respectively, indicating high affinity of the lectin towards the latter sugar. Lectin also bound adenine with estimated binding constant 1 x 104 M-1 implying its physiological role in plants. The native protein has total six Trp residues out of which, two are exposed on the surface and are in electropositive environment as revealed by fluorescence quenching with KI. The lectin exhibited thermostability upto 80°C retaining 50% of hemagglutination activity and showed fairly compact and stable structure as observed in the far-UV CD spectra. Also, the lectin remained active even after incubating in 6M GDn-HCl for 24 h, or at extreme pH or in 50% organic solvents.
Conclusion: The present study revealed that the chito-specific lectin purified from B. hispida has novel structural and functional stability at higher temperature, in a broad pH range, and also in the presence of higher concentrations of chemical denaturants. Binding to adenine indicates its importance in plant physiology.