Batokines: Mediators of Inter-Tissue Communication (a Mini-Review)

Purpose of Review This review highlights aspects of brown adipose tissue (BAT) communication with other organ systems and how BAT-to-tissue cross-talk could help elucidate future obesity treatments. Recent Findings Until recently, research on BAT has focused mainly on its thermogenic activity. New research has identified an endocrine/paracrine function of BAT and determined that many BAT-derived molecules, termed “batokines,” affect the physiology of a variety of organ systems and cell types. Batokines encompass a variety of signaling molecules including peptides, metabolites, lipids, or microRNAs. Recent studies have noted significant effects of batokines on physiology as it relates whole-body metabolism and cardiac function. This review will discuss batokines and other BAT processes that affect the liver, cardiovascular system, skeletal muscle, immune cells, and brown and white adipose tissue. Summary Brown adipose tissue has a crucial secretory function that plays a key role in systemic physiology.

Involvement of the Orexinergic System in Feeding

To know the processes involved in feeding, the dysregulation of hypothalamic neuropeptides promoting anorexigenic/orexigenic mechanisms must be investigated. Many neuropeptides are involved in this behavior and in overweight/obesity. Current pharmacological strategies for the treatment of obesity are unfortunately not very effective and, hence, new therapeutic strategies must be investigated and developed. Due to the crucial role played by orexins in feeding behavior, the aim of this review is to update the involvement of the orexinergic system in this behavior. The studies performed in experimental animal models and humans and the relationships between the orexinergic system and other substances are mentioned and discussed. Promising research lines on the orexinergic system are highlighted (signaling pathways, heterogeneity of the hypothalamic orexinergic neurons, receptor-receptor interaction, and sex differences). Each of the orexin 1 and 2 receptors plays a unique role in energy metabolism, exerting a differential function in obesity. Additional preclinical/clinical studies must be carried out to demonstrate the beneficial effects mediated by orexin receptor antagonists. Because therapies applied are in general ineffective when they are directed against a single target, the best option for successful anti-obesity treatments is the development of combination therapies as well as the development of new and more specific orexin receptor antagonists.

Regulation of homeostasis by neuropeptide Y: involvement in food intake

: Obesity leads to several metabolic disorders and, unfortunately, current pharmacological treatments for obesity are not very effective. In feeding mechanisms, the hypothalamus and some neuropeptides play an important role. Many data show that neuropeptide Y (NPY) is involved in these mechanisms. The aim of this review is to update the physiological actions mediated by the orexigenic peptide NPY, via its receptors, in the control of food intake and to review its involvement in food intake disorders. The relationships between NPY and other substances involved in food intake mechanisms, hypothalamic and extra-hypothalamic pathways involved in feeding and the potential pharmacological strategies to treat obesity will be discussed. Some research lines, focused on NPY, to be developed in the future are suggested. Neuropeptide systems are associated with redundancy and then therapies directed against a single target are generally ineffective. For this reason, other targets for the treatment of obesity are mentioned. It seems that combination therapies are the best option for successful anti-obesity treatments: new and more specific NPY receptor antagonists must be tested as anti-obesity drugs alone and in combination therapies.

The Isolation and Identification of α-Glucosidase and Lipase Inhibitors from Samoan Plant Extracts

<p>There is a growth in the problems relating to diabetes and obesity within the Pacific region. A recent study found that nearly 20% of the Samoan population suffer from type 2 diabetes. The same study found that rates of obesity are correspondingly high, at 53% of the male population and almost 77% of the female population. Healthcare costs are high, and so this study was initiated to focus specifically on an economical, available and socially acceptable way of introducing anti-diabetic and anti-obesity treatments. Inspired by ethnobotanical interests relating to the unknown potential of plants within the Pacific Island region, a set of five Samoan plants were selected for evaluation of their potential to provide leads for anti-diabetic or anti-obesity treatments. The work presented here was carried out in collaboration with the Scientific Research Organisation of Samoa (SROS) which collected plant samples and provided the extracts used for the present study. This study focused on the biological activity of the five selected Samoan plant extracts; Myristica fatua, Barringtonia samoensis, Barringtonia asiatica, Annona muricata and Neisosperma oppositifolia against pancreatic lipase and α-glucosidase enzymes. The enzyme bioassays were optimised and used to validate and identify potential anti-diabetic and anti-obesity treatments from compounds isolated and identified from the samples using LC-MS/MS and NMR spectroscopy. Two main fractions were carried forward for further fractionation and in vitro bioassay screening; one against lipase and the other against α- glucosidase. The known compound threo-dihydroguaiaretic acid was identified and isolated from Myristica fatua having the most potent lipase inhibition whereas a mixture of compounds containing alkaloids and the compound nirathin was obtained from Neisosperma oppositifolia in a fraction that exhibited the highest α-glucosidase inhibition. The kinetic modelling of both fractions were used to identify threo-dihydroguaiaretic acid having a mixed inhibition and the compound mixture inhibiting α-glucosidase competitively.</p>

The Isolation and Identification of α-Glucosidase and Lipase Inhibitors from Samoan Plant Extracts

<p>There is a growth in the problems relating to diabetes and obesity within the Pacific region. A recent study found that nearly 20% of the Samoan population suffer from type 2 diabetes. The same study found that rates of obesity are correspondingly high, at 53% of the male population and almost 77% of the female population. Healthcare costs are high, and so this study was initiated to focus specifically on an economical, available and socially acceptable way of introducing anti-diabetic and anti-obesity treatments. Inspired by ethnobotanical interests relating to the unknown potential of plants within the Pacific Island region, a set of five Samoan plants were selected for evaluation of their potential to provide leads for anti-diabetic or anti-obesity treatments. The work presented here was carried out in collaboration with the Scientific Research Organisation of Samoa (SROS) which collected plant samples and provided the extracts used for the present study. This study focused on the biological activity of the five selected Samoan plant extracts; Myristica fatua, Barringtonia samoensis, Barringtonia asiatica, Annona muricata and Neisosperma oppositifolia against pancreatic lipase and α-glucosidase enzymes. The enzyme bioassays were optimised and used to validate and identify potential anti-diabetic and anti-obesity treatments from compounds isolated and identified from the samples using LC-MS/MS and NMR spectroscopy. Two main fractions were carried forward for further fractionation and in vitro bioassay screening; one against lipase and the other against α- glucosidase. The known compound threo-dihydroguaiaretic acid was identified and isolated from Myristica fatua having the most potent lipase inhibition whereas a mixture of compounds containing alkaloids and the compound nirathin was obtained from Neisosperma oppositifolia in a fraction that exhibited the highest α-glucosidase inhibition. The kinetic modelling of both fractions were used to identify threo-dihydroguaiaretic acid having a mixed inhibition and the compound mixture inhibiting α-glucosidase competitively.</p>

Mediators of relations of obesity treatment-associated changes in mood and weight: extending cross-sectional research

Significant cross-sectional associations between mood and weight have been made in women; however, data on associated longitudinal effects and their psychological and behavioral mechanisms are required to inform obesity treatments that mostly have limited success beyond the very short term. Women participating in behavioral obesity treatments were assessed on psychological and behavioral measures, and weight change over 12 months. A treatment focused on physical activity and self-regulation (n = 67) had significantly better improvements than a treatment centered around weight-loss education (n = 64) on measures of mood (overall mood, depression, anxiety), self-regulation, emotional eating, eating behaviors, physical activity, and weight in women with obesity. Incorporating a lagged variable design, 12-month weight loss was significantly predicted (separately) by changes in overall negative mood, depression, and anxiety. When changes in measures of self-regulation, emotional eating, and eating behaviors were sequentially entered as mediators, mood change–weight change relationships were rendered non-significant. Significant mediation paths were: mood change→self-regulation change→weight change, and mood change→self-regulation change→eating behavior change→weight change. They were unaffected by the treatment group. Findings contributed to both theory and obesity intervention architectures via a design sensitive to the dynamic psychological and behavioral changes occurring within weight-loss processes.