D. Tafuri

Orexin-A controls sympathetic activity and eating behavior

It is extremely important for the health to understand the regulatory mechanisms of energy expenditure. These regulatory mechanisms play a central role in the pathogenesis of body weight alteration. The hypothalamus integrates nutritional information derived from all peripheral organs. This region of the brain controls hormonal secretions and neural pathways of the brainstem. Orexin-A is a hypothalamic neuropeptide involved in the regulation of feeding behavior, sleep-wakefulness rhythm, and neuroendocrine homeostasis. This neuropeptide is involved in the control of the sympathetic activation, blood pressure, metabolic status, and blood glucose level. This minireview focuses on relationship between the sympathetic nervous system and orexin-A in the control of eating behavior and energy expenditure. The “thermoregulatory hypothesis” of food intake is analyzed, underlining the role played by orexin-A in the control of food intake related to body temperature. Furthermore, the paradoxical eating behavior induced orexin-A is illustrated in this minireview.

Olanzapine blocks the sympathetic and hyperthermic reactions due to cerebral injection of orexin A.

Since experiments regarding a possible relation between olanzapine and orexin A has been scarcely reported in international literature, this experiment tested the effect of olanzapine on the sympathetic and thermogenic effects induced by orexin A. The firing rates of the sympathetic nerves to interscapular brown adipose tissue (IBAT), along with IBAT, colonic temperatures and heart rate were monitored in urethane-anesthetized male Sprague-Dawley rats before an injection of orexin A (1.5 nmol) into the lateral cerebral ventricle and over a period of 150 min after the injection. The same variables were monitored in rats with an intraperitoneal administration of olanzapine (10mg/kg bw), injected 30 min before the orexin administration. The results show that orexin A increases the sympathetic firing rate, IBAT, colonic temperatures and heart rate. This increase is blocked by the injection of olanzapine. These findings indicate that olanzapine affects the complex reactions related to activation of orexinergic system.

Quetiapine lowers sympathetic and hyperthermic reactions due to cerebral injection of orexin A

Since no experiment regarding a possible relation between quetiapine and orexin A has been reported in international literature, this experiment tested the effect of quetiapine on the sympathetic and thermogenic effects induced by orexin A. The firing rates of the sympathetic nerves to interscapular brown adipose tissue (IBAT), along with IBAT, colonic temperatures and heart rate were monitored in urethane-anesthetized male Sprague-Dawley rats before an injection of orexin A (1.5 nmol) into the lateral cerebral ventricle and over a period of 150 min after the injection. The same variables were monitored in rats with an intraperitoneal administration of quetiapine (5 or 10 mg/kg bw), injected 30 min before the orexin administration. The results show that orexin A increases the sympathetic firing rate, IBAT, colonic temperatures and heart rate. This increase is delayed or reduced by the injection of quetiapine. These findings indicate that quetiapine affects the complex reactions related to activation of orexinergic system. Possible influences on the control of body weight and temperature are discussed.

Metabolic and cardiopulmonary effects of detraining after a structured exercise training programme in young PCOS women

Objectiveu2003 The aim of the present study was to determine if the favourable cardiopulmonary and metabolic benefits induced by exercise training (ET) programme are maintained after its cessation.

Role of Orexin in Obese Patients in the Intensive Care Unit

Understanding the regulation of appetite and energy expenditure mechanisms is essential for the health and disease. The recognition that the distribution of these regulatory mechanisms plays a central role in the pathogenesis of obesity and associated metabolic syndrome is not new, and it is even more interesting to understand what happens in an obese patient in the Intensive Care Unit (ICU). This review focuses on the catabolic role of orexin, which paradoxically coexists with its anabolic feeding-inducing role. The goal of this review is to provide insight into the biological mechanism governing orexin’s role in energy expenditure, discuss its significance in the context of ICU. Mammals possess a specialized tissue termed Brown Adipose Tissue (BAT) that expends calories to counteract hypothermia. The ability to enhance energy expenditure by manipulating BAT activity is attractive from a therapeutic standpoint, in light of the discovery of metabolically active BAT in adult humans. The finding of a relationship between BAT and orexins levels suggests new research on the possible roles of orexins in many anomalies of energy expenditure, including those of obese patients in the ICU.

Oral contraceptives versus physical exercise on cardiovascular and metabolic risk factors in women with polycystic ovary syndrome: a randomized controlled trial

Although oral contraceptives (OCs) are one the most widespread therapy in young polycystic ovary syndrome (PCOS) women and physical exercise represents a crucial first step in the treatment of overweight and obese PCOS, no studies were performed to compare the effects on cardiovascular risk (CVR) of OCs and physical exercise in PCOS.

Modifications of Activity of Autonomic Nervous System, and Resting Energy Expenditure in Women Using Hormone-Replacement Therapy

Menopause is a significant period characterized by physiological change. Hormonal changes are largely related to estrogen depletion and subsequent cessation of ovarian function. This study analyzed vegetative modulation, expressed as heart rate variability (HRV) power spectral analysis, resting energy expenditure, and body composition in women in post-menopause with and without hormone-replacement therapy (HRT). 87 Sedentary women were enrolled, 41 (age: 53-54) women with BMI of 21.6 ± 2.6 kg/m2 were on HRT and 46 (age: 52-63) with BMI of 22.4 ± 1.8 kg/m2 were not. This experiment marks aspects regarding the relationship between the autonomic nervous system and body weight in HRT and menopause.

Dietary Supplements Use in Competitive and Non-Competitive Boxer: An Exploratory Study

Intensity training, talent, and an adequate diet represent the crucial factors for the success of athletes. Unfortunately, athletes prefer intaking substances to quicker and easier increase their performance compared to traditional training. For this reason there has been a significant spread of enhancing substances drugs and dietary supplements (DS), although, as already broadly evidenced, the abuse of those substances could seriously damage athletes’ health. Indeed, DS could contain substances that are not declared on the label, which are banned by the World Anti-Doping Agency (WADA). This exploratory study aims to investigate DS phenomenon, specifically, we want to describe this phenomenon among boxers, analyzing typologies of DS intaken, knowledge about DS, main reasons for justifying DS abuse, and places where boxers buy them and potential consultants about suggesting their consumption. Data were collected through a total of 214 anonymous self-report questionnaires administered to boxers in Campania (Italy), 169 questionnaires were considered valid. The study collects data exclusively for male athletes. Indeed, the results demonstrate that boxers, mainly men (88.4% of the sample), practice sport mostly for fun and they intake DS for balancing out nutritional deficiencies and having more energy. Mineral salts (N=88) and vitamins (N=85) are broadly intaken compared to other substances. The consumption of DSis recommended by coach in the competitive athletes (N=33), against non-competitive boxer whom consultant is the doctor (N=25). Boxers mostly buy the supplements in the drugstore. In summary, the results demonstrate that boxers widely intake DS for improving their performance. Also, implications for research and practice are discussed.