Reduced adiposity in bitter melon (Momordica charantia) fed rats is associated with lower tissue triglyceride and higher plasma catecholamines

Slower weight gain and less visceral fat had been observed when rats fed a high-fat diet were supplemented with freeze-dried bitter melon (BM) juice; the metabolic consequences and possible mechanism(s) were further explored in the present study. In a 4-week experiment, rats were fed a low-fat (70 g/kg) or a high-fat (300 g/kg) diet with or without BM (7.5 g/kg or 0.75%). BM-supplemented rats had lower energy efficiency, visceral fat mass, plasma glucose and hepatic triacylglycerol, but higher serum free fatty acids and plasma catecholamines. In the second experiment, 7-week BM supplementation in high-fat diet rats led to a lowering of hepatic triacylglycerol (P<0.05) and steatosis score (P<0.05) similar to those in rats fed a low-fat diet. BM supplementation did not affect serum and hepatic cholesterol. However, plasma epinephrine and serum free fatty acid concentrations were increased (P<0.05). In the third experiment, BM(7.5 and 15 g/kg) and 1.5 % BM lowered triacylglycerol concentration in red gastrocnemius and tibialis anterior (P<0.05) muscle, but a dose-response effect was not observed. These data suggest that chronic BM feeding leads to a general decrease in tissue fat accumulation and that such an effect is mediated in part by enhanced sympathetic activity and lipolysis. BM or its bioactive ingredient(s) could be used as a dietary adjunct in the control of body weight and blood glucose. © The Authors 2005.published_or_final_versio

Alisol B 23-acetate induces autophagic-dependent apoptosis in human colon cancer cells via ROS generation and JNK activation

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Nutrients, supplements safety and toxicity

Invited Talk 4Conference Theme: Food Safety: from Experience to PerspectivesObtaining adequate amount of essential nutrients at different stages of life is critical to normal development and health maintenance. The feeling of inadequacy, however, is pervasive even in affluent societies. This sentiment has spawned the exponential use of dietary supplements (including nutrients, nutraceuticals and herbal products) worldwide. Such consumer behaviour perhaps precipitates from the views that science has not fully unveiled needs of the human body and that if something is good, more are better. When it comes to inadequate intake of essential nutrient(s), the positive benefits of ...postprin

The validation of BMI as an obesity criterion in Chinese adults

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Oxyresveratrol supplementation to C57bl/6 mice fed with a high-fat diet ameliorates obesity-associated symptoms

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Isolation of leptin-binding peptides from a random peptide phage library

Leptin plays a role in regulating the body weight in mice. Injection of recombinant mouse leptin expressed in Escherichia coli reduced the food intake and body weight in normal, ob/ob and diet-induced obesity mice. Hyperglycemia, hyperinsulinemia and hypothermia can also be corrected in ob/ob mice after leptin injection. Leptin is a 16-kDa secretory protein comprising 167 amino acids produced in adipose tissue and is secreted to blood stream. In this study, a recombinant mouse leptin was generated and purified from a baculovirus expression system. This protein was used to identify putative ligands using a phage library of random peptides. Three leptin-binding phage clones were found, which were characterized by DNA sequencing and ELISA methods. The amino acid sequences of the reactive peptides are: LAYCSDPVRCLVWWY, MFWlSAVSFVDHALV and LVLVLSAFLCCGVG. All three clones bound to recombinant human and mouse leptins. These peptides may be useful tools to study leptin-receptor interaction, food intake and body weight regulation.postprin

Effects of essential amino acids on food and water intake of rats

This study examined the effects of selected groups of essential amino acids (EAAs), given by gavage, on short-term food and water intake. Amino acid groups were selected on the basis of their common physiologic functions in relation to current hypotheses on the role of amino acids in food intake control, and the quantities given were based on the proportions in 1.5 g of the EAA content of albumin. The complete EAA mixture (1.5 g) suppressed food intake by an average of 60 and 37% during the 1st and 2nd h of feeding, respectively, but had no influence on feeding in the subsequent 12 h. Total daily (14 h) intake was decreased by 9%. With the exception of the aromatic amino acid (Phe + Tyr + Trp, 0.34 g) group, all groups significantly decreased food intake by a comparable magnitude (32%) during the 1st h. In this time period, rats given the EAAs, Arg + Met + Val (0.38 g), and Arg + His + Lys (0.44 g) mixtures increased their water intake, whereas intake by rats given the Phe + Tyr + Trp + Thr (0.46 g) and Ile + Leu + Val (0.45 g) mixtures was unchanged. Thus, the food intake suppression caused by EAAs was not accounted for by an equal effect of its component amino acid groups. As well, food intake suppression by amino acid groups was not explained by increased water consumption, nor was it simply related to the quantity of nitrogen provided by the treatment.published_or_final_versio

Resting metabolic rate and thermic effects of a sucrose-sweetened soft drink during the menstrual cycle in young Chinese women

The resting metabolic rate (RMR) and thermic effects (TEF) of a sucrose- sweetened soft drink in a group (n = 19) of ovulating young Chinese women were determined by indirect calorimetry in the midfollicular and midluteal phases of the menstrual cycle. Urinary luteinizing hormone surge was used to confirm ovulation. The RMR was measured twice in each phase and found to be similar (F(1,18) = 0.863) across the follicular (5018 kJ/24 h) and the luteal (5098 kJ/24 h) phases. Within each phase and on separate days, subjects were given water (280 mL) or sucrose-sweetened soft drink (539 kJ). Soft drink, but not water, consumption increased energy expenditure over a period of 45 min. Compared with the follicular phase, a small but significant increase in TEF (kJ/45 min) was observed in the luteal phase (t = 2.434, p < 0.05). Energy expenditure after drinking the soft drink, however, was similar in the two phases. RMR was positively correlated with TEF (r = 0.613, p < 0.01) and net TEF (r = 0.648, p < 0.005) in the luteal but not the follicular phase. In ovulating women, the thermic effect of sucrose is influenced by the phase of the menstrual cycle.published_or_final_versio