Current Protein and Peptide Science - Volume 12, Issue 4, 2011

Energy balance of mammals is a complex system that involves a great variety of factors: ingestion of calorie containing substances has to be counterbalanced by various components of the overall metabolic rate and energy expenditure (e.g., heat loss). When this balance is well established, it means an optimal development and later stable maintenance of body weight, well-regulated body temperature [1, 2] and Read More

Aging affects energy homeostasis and fuel metabolism in a form of either an increased body mass and glucose intolerance that may lead to obesity and type 2 diabetes or loss of appetite that also may seriously compromise health status. The data, obtained mainly in rat, suggest that aging suppresses the expression and action of potent orexigenic peptides such as predominantly neuropeptides NPY and orexins and peripher Read More

Ghrelin is a stomach-derived peptide discovered as a ligand of the orphan G-protein coupled receptor. Ghrelin is now recognized as a major orexigenic neuropeptide. Immunohistochemical studies demonstrated that centrally administered ghrelin induced c-fos protein expression in many areas in the brain. Indeed, centrally administered ghrelin has various effects such as stimulating feeding, arousal, increasing gastric acid Read More

Anapyrexia, which is a regulated fall in core temperature, is beneficial for animals and humans when the oxygen supply is limited, e.g., hypoxic, ischemic, or histotoxic hypoxia, since at low body temperature the tissues require less oxygen due to Q10. Besides hypoxia, anapyrexia can be induced various exogenous and endogenous substances, named cryogens. However, there are only a few reports investigating endogen Read More

Several peptides are produced and released from endocrine cells scattered within the gastric oxyntic and the small intestinal mucosa. These peptide hormones are crucially involved in the regulation of gastrointestinal functions and food intake by conveying their information to central regulatory sites located in the brainstem as well as in the forebrain, such as hypothalamic nuclei. So far, ghrelin is the only known horm Read More

Aging in mammals associates with the development of peripheral insulin resistance. Additionally, adiposity usually increases with aging and this could play a relevant role in the gradual impairment of insulin action. In fact, fat accretion leads to changes in the expression and circulating concentrations of factors originated in adipose tissue like leptin, resistin and inflammatory cytokines which have been shown to modulat Read More

With advancing age most aspects of the peptidergic regulation of energy balance are altered. The alteration involves both the peripheral peptides derived from the adipose tissue or the gastrointestinal tract and the peptides of the central nervous system (brainstem and hypothalamus). In general, the expression of orexigenic peptides and their receptors decreases with age, while that of the anorexic ones rather increases, Read More

Cations are specifically recognized by numerous proteins. Cations may play a structural role, as cofactors stabilizing their binding partners, or a functional role, as cofactors activating their binding partners or being themselves involved in enzymatic reactions. Despite their small size, their charge density and their specific interaction with highly charged residues allow them to induce significant conformational changes on th Read More