Dietary energy restriction is the only proven method for extending lifespan and slowing aging in mammals, while maintaining health and vitality. Although the first experiments in this area were conducted over 60 y ago in rodents, possible applicability to primates has only been examined in controlled studies since 1987. Our project at the National Institute on Aging began with 3-0 male rhesus and 30 male squirrel monkeys of various ages over their respective life spans.
Dietary caloric restriction is the most reproducible means of extending longevity and maintaining health and vitality. It has been shown to be relevant to a wide rage of species, including primates. Examination of key markers of the calorically restricted phenotype, such as plasma insulin, dehydroepiandrosterone sulfate, and body temperature, suggest that they may predict longevity in humans as well. However, most people would be unwilling or unable to adopt the 30% to 40% reduction in food intake necessary to achieve optimal health and longevity benefits.
JAMA: the journal of the American Medical Association
CONTEXT: Prolonged calorie restriction increases life span in rodents. Whether prolonged calorie restriction affects biomarkers of longevity or markers of oxidative stress, or reduces metabolic rate beyond that expected from reduced metabolic mass, has not been investigated in humans. OBJECTIVE: To examine the effects of 6 months of calorie restriction, with or without exercise, in overweight, nonobese (body mass index, 25 to <30) men and women.
DHEA and DHEAS are steroids synthesized in human adrenals, but their function is unclear. In addition to adrenal synthesis, evidence also indicates that DHEA and DHEAS are synthesized in the brain, further suggesting a role of these hormones in brain function and development. Despite intensifying research into the biology of DHEA and DHEAS, many questions concerning their mechanisms of action and their potential involvement in neuropsychiatric illnesses remain unanswered.
To fall in love is the first step in pair formation in humans and is a complex process which only recently has become the object of neuroscientific investigation. The little information available in this field prompted us to measure the levels of some pituitary, adrenal and gonadal hormones in a group of 24 subjects of both sexes who had recently (within the previous six months) fallen in love, and to compare them with those of 24 subjects who were single or were part of a long-lasting relationship.
Early-stage romantic love involves reorganization of neurohormonal systems and behavioral patterns marked by mutual influences between the partners' physiology and behavior. Guided by the biobehavioral synchrony conceptual frame, we tested bidirectional influences between the partners' hormones and conflict behavior at the initiation of romantic love. Participants included 120 new lovers (60 couples) and 40 singles.
Yoga represents a fascinating mind-body approach, wherein body movements (asana), breathing exercises (pranayama) and meditation are integrated into a single multidimensional practice. Numerous beneficial mental and physical effects have been classically ascribed to this holistic ancient method. The purpose of the present study has been to examine the effects of long-term yoga practice on Subjective Sleep Quality (SSQ) and on several hormonal parameters of the hypothalamus-pituitary-adrenal (HPA) axis.
OBJECTIVE: this analysis was to investigate the effects of dehydroepiandrosterone (DHEA) on cardiovascular risk factors in older women with frailty characteristics. DESIGN, SETTING AND PARTICIPANTS: the study was a double-blind, randomised, placebo-controlled trial of 99 women (mean 76.6 +/- 6.0 year) with the low DHEA-S level and frailty. INTERVENTION: participants received 50 mg/day DHEA or placebo for 6 months; all received calcium (1,000-1,200 mg/day diet) and supplement (combined) and cholecalciferol (1,000 IU/day).
Ductal morphogenesis of the mammary gland occurs largely in the early pubertal period under the influence of ovarian sex hormones. In this study we characterized developing ductal structures in breast tissue of 14 female prepubertal or early pubertal rhesus monkeys (average age, 2.6 +/- 0.1 years). Serum estradiol concentrations ranged from < 5.0 to 61.2 pg/ml, while progesterone concentrations were low in all animals (< 0.6 ng/ml). No corpora lutea were seen on ovarian histology.