Search results for "hormone"
showing 10 items of 2056 documents
Estrogenic Modulation of Longevity by Induction of Antioxidant Enzymes
2010
In many species including humans, females live longer than males. We and others have observed that mitochondria from females of Wistar rats and of OF1 mice produce half the amount of peroxide produced by males. We attributed this to a change in the expression of antioxidant, longevity-related genes. We have found that in those species in which females live longer than males, estrogens activate longevity-related genes, particularly antioxidant ones. It should be emphasized that estrogens do not act as antioxidants because of their phenolic ring but rather they act indirectly; that is, they behave as hormones and bind to estrogen receptors, which eventually leads to the upregulation of the ex…
Changes in Exercise Performance and Hormonal Concentrations Over a Big Ten Soccer Season in Starters and Nonstarters
2004
As a consequence of the physiological demands experienced during a competitive soccer season, the antagonistic relationship between anabolic and catabolic processes can affect performance. Twenty-five male collegiate soccer players were studied throughout a season (11 weeks) to investigate the effects of long-term training and competition. Subjects were grouped as starters (S; n = 11) and nonstarters (NS; n = 14). Measures of physical performance, body composition, and hormonal concentrations (testosterone [T] and cortisol [C]) were assessed preseason (T1) and 5 times throughout the season (T2-T6). Starters and NS participated in 83.06% and 16.95% of total game time, respectively. Nonstarte…
Postembryonic development of Zophobas atratus Fab. (Coleoptera: Tenebrionidae) under crowded or isolated conditions and effects of juvenile hormone a…
1995
Abstract Pupation in Zophobas atratus is dependent on isolation and this provides a model for study of the onset of metamorphosis in beetles. We have analyzed the effects of isolation vs grouping on certain developmental parameters; the number of larval instars; their duration and weight. Sex differences were detected, such as the occurrence of regressive moults in females. Moreover, the development of Z. atratus is discussed in relation to Tenebrio molitor , the physiological timing of which appeared in part extendable to Z. atratus . Experiments show that 4–6 days of isolation are required for commencement of metamorphosis, as indicated by an immobile crooked posture observed at the end o…
Field application of the juvenile hormone analogue fenoxycarb against hopper bands of Locusta migratoria capito in Madagascar
1997
Summary Field trials have been carried out to examine the suitability of the JHA fenoxycarb in locust control. Laboratory tests have shown that a variety of JHAs, including fenoxycarb, applied to last instar larvae increased mortality, induced morphogenetic defects during metamorphosis, reduced fertility and provoked solitarisation of gregarious hoppers. The phase shift was indicated by green coloration and the acquisition of morphological and behavioural characteristics typical for solitary locusts. The present field experiments should clarify whether or not the effects observed in the laboratory are also observed with hopper bands in their natural habitat and if swarm formation and emigra…
Appetite and Obesity
2011
Orexin (hypocretin) plays an important role in promoting wakefulness [1]. It stimulates wakefulness when injected in the cerebral ventricles, in the periventricular nucleus, dorsomedial hypothalamus, or lateral hypothalamus [2, 3]. Orexinergic neurons originate from the lateral hypothalamus and have projections to most parts of the central nervous system including the brain stem. The lack of orexin and/or orexin receptors is linked to narcolepsy [4–6].
Leptin and Leptin Receptor Are Expressed in the Human Endometrium and Endometrial Leptin Secretion Is Regulated by the Human Blastocyst1
2000
Embryonic implantation is a crucial event for the human reproductive function. Cytokines and paracrine molecules have been proposed as putative local regulators of this process. The leptin or the OB protein has been linked to the reproductive function and inflammatory response. In the present study, we describe for the first time the expression of leptin and leptin receptor (long form) in the secretory endometrium and that endometrial leptin secretion is regulated in vitro by the human blastocyst. Leptin and leptin receptor messenger RNA and protein were identified in secretory endometrium and in cultured endometrial epithelial cells (EECs) by RT-PCR, Western blot, and immunohistochemistry.…
Impairment of leptin/leptin receptor pathway in nasal epithelium from allergic turbinates
2016
BACKGROUND: Allergic rhinitis (AR) is characterized by a remodeling of nasal epithelium. Leptin adipokine has been already identified as a marker of homeostasis in human bronchial epithelial of asthmatics. TGF-β is a multi-functional cytokine and conflicting findings exist regarding its role in the remodeling responses of the upper airways in allergic rhinitis. OBJECTIVE: We sought to investigate ex-vivo the expression of leptin/leptin receptor pathway and TGF-β in human nasal epithelium. METHODS: 41 biopsies of inferior turbinates obtained from allergic patients with AR (A, n = 20) and from healthy control subjects (C, n = 21) were analyzed for leptin/leptin receptor and for TGF-β 1, 2, 3 …
Neuroendocrine Regulation Of The IL-27-Dependent Immune Response In Macrophages
2013
Abstract The central nervous system has the ability for modulating immune responses, but the molecular mechanisms of such interactions are only partly understood. Interleukin-27 (IL-27) is a heterodimeric protein and structurally related to the IL-12 family of cytokines. IL-27 is composed of the subunits EBI3 and p28. The biological functions of IL-27 have been described as either anti-inflammatory or pro-inflammatory depending on the experimental models studied. In the current study, we investigated how production of Interleukin-27 (IL-27) is regulated by neuroendocrine hormones. We focused our work on the subunit p28, since EBI3 is also present in IL-35 and therefore is not a specific com…
Adipokines and Lipoproteins: Modulation by Antihyperglycemic and Hypolipidemic Agents
2014
Abstract Adipose tissue is an endocrine organ that secretes a number of hormones and metabolically active substances that impact energy metabolism and insulin sensitivity. These inflammatory markers are collectively referred to as adipocytokines, or adipokines. Adipose tissue's functional capacity and metabolic activity vary among individuals, thus partly explaining the incomplete overlap between obesity and the metabolic syndrome. The functional failure of adipose tissues results in changed energy delivery and impaired glucose consumption, triggering self-regulatory mechanisms to maintain homeostasis. Antihyperglycemic, hypolipidemic, antiobesity, and angiotensin II receptor blocker drugs …
Postnatal Overfeeding in Rodents by Litter Size Reduction Induces Major Short- and Long-Term Pathophysiological Consequences
2013
Numerous studies have demonstrated that the early postnatal environment can influence body weight and energy homeostasis into adulthood. Rodents raised in small litters have been shown to be a useful experimental model to study the short- and long-term consequences of early overnutrition, which can lead to modifications not only in body weight but also of several metabolic features. Postnatal overfeeding (PNOF) induces early malprogramming of the hypothalamic system, inducing acquired persisting central leptin and insulin resistance and an increase in orexigenic signals. Visceral white adipose tissue, lipogenic activity, and inflammatory status are increased in PNOF rodents, while brown adi…