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1.
In this study, metabolic changes of several adipose depots as caused by aging were investigated. Key enzyme activity of glutaminolysis, pentose-phosphate pathway and Krebs cycle were measured. The rates of lipogenesis from 3H2O, lipoprotein lipase (LPL) activity and rate of lipolysis in vitro were also determined. The results obtained indicate a reduced capacity for lipogenesis in several adipose depots by aging. The authors concluded that hypertrophy of adipose tissue reported during aging is possible due to increased LPL activity and reduced rate of lipolysis.  相似文献   

2.
Hyperinsulinism in infancy: from basic science to clinical disease   总被引:14,自引:0,他引:14  
Ion channelopathies have now been described in many well-characterized cell types including neurons, myocytes, epithelial cells, and endocrine cells. However, in only a few cases has the relationship between altered ion channel function, cell biology, and clinical disease been defined. Hyperinsulinism in infancy (HI) is a rare, potentially lethal condition of the newborn and early childhood. The causes of HI are varied and numerous, but in almost all cases they share a common target protein, the ATP-sensitive K+ channel. From gene defects in ion channel subunits to defects in beta-cell metabolism and anaplerosis, this review describes the relationship between pathogenesis and clinical medicine. Until recently, HI was generally considered an orphan disease, but as parallel defects in ion channels, enzymes, and metabolic pathways also give rise to diabetes and impaired insulin release, the HI paradigm has wider implications for more common disorders of the endocrine pancreas and the molecular physiology of ion transport.  相似文献   

3.
4.
Genetic mediated physiological processes that rely on both pharmacological and nutritional principles hold great promise for the successful therapeutic targeting of reduced carbohydrate craving, body-friendly fat loss, healthy body recomposition, and overall wellness. By integrating an assembly of scientific knowledge on inheritable characteristics and environmental mediators of gene expression, we review the relationship of genes, hormones, neurotransmitters, and nutrients as they correct unwanted weight gain coupled with unhappiness. In contrast to a simple one-locus, one-mechanism focus on pharmaceuticals alone, we hypothesize that the use of nutrigenomic treatment targeting multi-physiological neurological, immunological, and metabolic pathways will enable clinicians to intercede in the process of lipogenesis by promoting lipolysis while attenuating aberrant glucose cravings. In turn, this approach will enhance wellness in a safe and predictable manner through the use of a Genetic Positioning System (GPS) Map. The GPS Map, while presently incomplete, ultimately will serve not only as a blueprint for personalized medicine in the treatment of obesity, but also for the development of strategies for reducing many harmful addictive behaviors and promoting optimal health by using substances compatible with the body’s immune system.  相似文献   

5.
Gut hormones: emerging role in immune activation and inflammation   总被引:1,自引:0,他引:1  
Gut inflammation is characterized by mucosal recruitment of activated cells from both the innate and adaptive immune systems. In addition to immune cells, inflammation in the gut is associated with an alteration in enteric endocrine cells and various biologically active compounds produced by these cells. Although the change in enteric endocrine cells or their products is considered to be important in regulating gut physiology (motility and secretion), it is not clear whether the change plays any role in immune activation and in the regulation of gut inflammation. Due to the strategic location of enteric endocrine cells in gut mucosa, these gut hormones may play an important role in immune activation and promotion of inflammation in the gut. This review addresses the research on the interface between immune and endocrine systems in gastrointestinal (GI) pathophysiology, specifically in the context of two major products of enteric endocrine systems, namely serotonin (5‐hydroxytryptamine: 5‐HT) and chromogranins (Cgs), in relation to immune activation and generation of inflammation. The studies reviewed in this paper demonstrate that 5‐HT activates the immune cells to produce proinflammatory mediators and by manipulating the 5‐HT system it is possible to modulate gut inflammation. In the case of Cgs the scenario is more complex, as this hormone has been shown to play both proinflammatory and anti‐inflammatory functions. It is also possible that interaction between 5‐HT and Cgs may play a role in the modulation of immune and inflammatory responses. In addition to enhancing our understanding of immunoendocrine interaction in the gut, the data generated from the these studies may have implications in understanding the role of gut hormone in the pathogenesis of both GI and non‐GI inflammatory diseases which may lead ultimately to improved therapeutic strategies in inflammatory disorders.  相似文献   

6.
Neuroscience and Behavioral Physiology - Melanocortins form a class of regulatory peptide currently under active study; these include such biologically active substances as adrenocorticotropic...  相似文献   

7.
Nowadays, in industrialised societies, it is fashionable for women to be slim. However, throughout history, this has not always been the case, especially as "cellulite" (cellulitis) was full of typically feminine symbols. The ideal feminine silhouette has changed with the rhythm of cultures. Cellulitis is an inappropriate term used by women to describe curves which they judge to be too plump and not very aesthetic, mostly around the thighs and hips. This lipodystrophy of the adipose tissue represents approximately 25% of a woman's body weight. It is clinically characterised by an "orange peel" skin surface, which is a result of the excessive development of the volume of the adipocytes organised in lobules within the walls of the unstretchable conjunctive tissue. This phenomenon is associated with an insufficiency of the venous tonus and an increase in the capillary permeability, which both contribute to an increase in the infiltration of water in the tissue. In reality, the understanding of cellulite has truly progressed with research based on adipocyte functions. An adipocyte is a metabolically active cell which plays a central role in the control of the energetic balance of the organism. In order to assume this role, it possesses all the enzymatic equipment necessary for synthesis (lipogenesis) and for triglyceride storage, mobilisation and liberation as free fatty acids (lipolysis). During these last few years, as well as this role as an energetic reserve which manages lipogenesis/lipolysis balance, the adipocyte has acquired the status of an endocrine and paracrine cell through the identification of numerous secreted factors. When we look back at the history of slimming products launched on the market since the 1980's, we can notice the role of the adipocyte tool and understand its functions in the choice of active ingredients, the development of complementary actions, the importance of the texture, the evolution of methods used to evaluate the efficacy on human volunteers and of course, we must not forget the women satisfaction and the power of seduction through words.  相似文献   

8.
Summary The rates of lipolysis and lipogenesis in adipocytes, isolated from biopsy samples of subcutaneous fat, was assessed by estimation of glycerol release during a 30-min incubation, and of the incorporation of13C-glucose into lipids during a 1-h incubation at 37° C, respectively. The subjects were six highly-qualified, active endurance sportsmen, eight former endurance sportsmen of international class, and six untrained young men. In the active sportsmen the basal rate of lipolysis was about half of that in the previously-active sportsmen and the untrained subjects, but after the addition of adrenaline (10–4 or 5 × 10–4 mol · l–1) the lipolysis rate was the highest. No differences were observed in the lipolytic rates in the former sportsmen compared to the untrained subjects. Gases of a comparatively high level of lipogenesis were found in the trained subjects. The addition of insulin (9 U · ml–1) to isolated adipocytes caused a significant augmentation of individual rates of lipogenesis in the active sportsmen and the untrained persons but not in the previously-active sportsmen. In comparison with the active sportsmen, the previously active sportsmen revealed an increased basal rate of lipolysis and a reduced sensitivity to the lipogenic action of insulin. These findings suggest that these changes may have had significance in avoiding an increase of adipose tissue after a decrease in energy expenditure due to a change in physical activity.  相似文献   

9.
脂肪组织不仅是能量储存器官,还具有复杂的内分泌功能,可分泌多种蛋白,称为“脂肪因子”,脂联素即是其中之一.血液中脂联素较其他脂肪因子高出许多,具有改善胰岛素抵抗、增加胰岛素敏感性、调节糖类、脂质代谢、抗动脉粥样硬化和保护心肌等作用,越来越多的研究发现脂联素在自身免疫性疾病如类风湿关节炎(RA)中也有重要作用,对RA发病中涉及的软骨细胞、滑膜成纤维细胞均有影响,并与病情活动相关,或许可成为RA的潜在治疗靶点.  相似文献   

10.
Resident peritoneal cells of BALB/c mice were found to release two types of mediators influencing physiological interferon synthesis, a nondialysable stimulator and a dialysable low molecular inhibitor. The influence of macrophage secreted, biologically active substances on interferon production is discussed. Their participation in the induction of physiological interferons is considered.  相似文献   

11.
As a result of the metabolic activities of numerous anaerobic microorganisms with sterols, bile acids and steroid hormones as substrates in connection with the enterohepatic circulation of these compounds, the intestine may be considered as an “endocrine” active site or organ. The review summarizes transformations of steroids by anaerobic intestinal bacteria, the physiological and supposed pathophysiological meaning thereof. The aim is to recommend further investigation in this field with respect to both the elucidation of the reactions and biological responses.  相似文献   

12.
One decade has passed since seminal publications described macrophage infiltration into adipose tissue (AT) as a key contributor to inflammation and obesity-related insulin resistance. Currently, a PubMed search for ‘adipose tissue inflammation’ reveals over 3500 entries since these original reports. We now know that resident macrophages in lean AT are alternatively activated, M2-like, and play a role in AT homeostasis. In contrast, the macrophages in obese AT are dramatically increased in number and are predominantly classically activated, M1-like, and promote inflammation and insulin resistance. Mediators of AT macrophage (ATM) phenotype include adipokines and fatty acids secreted from adipocytes as well as cytokines secreted from other immune cells in AT. There are several mechanisms that could explain the large increase in ATMs in obesity. These include recruitment-dependent mechanisms such as adipocyte death, chemokine release, and lipolysis of fatty acids. Newer evidence also points to recruitment-independent mechanisms such as impaired apoptosis, increased proliferation, and decreased egress. Although less is known about the homeostatic function of M2-like resident ATMs, recent evidence suggests roles in AT expansion, thermoregulation, antigen presentation, and iron homeostasis. The field of immunometabolism has come a long way in the past decade, and many exciting new discoveries are bound to be made in the coming years that will expand our understanding of how AT stands at the junction of immune and metabolic co-regulation.  相似文献   

13.
Elemental selenium and glutathione reductase   总被引:9,自引:0,他引:9  
Selenium is an essential trace element important to several metabolic processes, although selenium in the chemical form of elemental selenium (Se degree) is commonly believed to be biologically inert. Recent data shows that colloidal suspensions of red amorphous elemental selenium are more easily reduced than previously thought, and that such reductions can potentially take place under biological conditions. The enzyme glutathione reductase, already known to be involved in selenium metabolism, is a good candidate to mediate the reduction of colloidal selenium to hydrogen selenide (H2Se), a compound of established biological activity. The implications of this hypothesis include the possibility that elemental selenium may be biologically active at least under some conditions, and that glutathione reductase may function in selenium metabolism primarily by maintaining the glutathione concentration in a reduced state.  相似文献   

14.
Bykova A  Baker E 《Natural immunity》1998,16(5-6):198-206
This paper outlines research that has led to the concept of the inevitable participation of the immune system in an organism's chemical homeostasis. This function of the immune system is tentatively named the 'immune mechanism of the chemical homeostasis' (IMCH). It is based on the theory of a permanent physiological synthesis of antibodies to endogenous biologically active substances. Minimal accumulation of biologically active substances as a result of the influence of different factors specifically activates the immune system in order to maintain its chemical homeostasis. The concept suggests the necessity of widening the notion of the range of the immune system's censorial functions. The concept explains the preexistence of immunocompetent cells preadapted to biologically active substances and autoantibodies specific to them; the natural clonality of the B lymphocyte pool; the polyclonal lymphocyte activation triggered by mitogens, foreign proteins, erythrocytes, and microbes, and tolerance to drugs.  相似文献   

15.
Adipose tissue is the primary energy reservoir in the body and an important endocrine organ that plays roles in energy homeostasis, feeding, insulin sensitivity, and inflammation. While it was tacitly assumed that fat in different anatomical locations had a common origin and homogenous function, it is now clear that regional differences exist in adipose tissue characteristics and function. This is exemplified by the link between increased deep abdominal or visceral fat, but not peripheral adipose tissue and the metabolic disturbances associated with obesity. Regional differences in fat function are due in large part to distinct adipocyte populations that comprise the different fat depots. Evidence accrued primarily in the last decade indicates that the distinct adipocyte populations are generated by a number of processes during and after development. These include the production of adipocytes from different germ cell layers, the formation of distinct preadipocyte populations from mesenchymal progenitors of mesodermal origin, and the production of adipocytes from hematopoietic stem cells from the bone marrow. This review will examine each of these process and their relevance to normal adipose tissue formation and contribution to obesity-related diseases.  相似文献   

16.
Peptide hormones, usually considered to be endocrine factors responsible for communication between tissues remotely located from each other, are increasingly being found to be synthesized in developing tissues, where they act locally. Several hormones are now known to be produced in developing tissues that are unrelated to the endocrine gland of origin in the adult. These hormones are synthesized locally, and are active as differentiation and survival factors, before the developing adult endocrine tissue becomes functional. There is increasing evidence for paracrine and/or autocrine actions for these factors during development, thus, placing them among the conventional growth and differentiation factors. We review the evidence for the view that thyroid hormones, growth hormone, prolactin, insulin, and parathyroid hormone-related protein are developmental growth and differentiation factors.  相似文献   

17.
The use of increasingly refined techniques in endocrinologic research resulted in a challenge to the classical concept of hormones. The regulatory activity of the highly complicated neuroendocrine system is mediated not only by hormones but by neurotransmitters, paracrine substances, and possibly by substances secreted into the gastrointestinal lumen as well. The system is divided into the central and peripheral nervous system and the endocrine system. The latter consists of the endocrine glands and the disseminated endocrine system. Research into the activities of the system will result in important advances in the fields of physiology, pathophysiology and pathology.  相似文献   

18.
Today, there are still uncertainties about the role of exogenous fat on body fat regulation. Early models of energy utilization (for example, Kleiber's, early 20th century) failed to take into account the nature of substrate oxidized in the control of food intake, whereas more recent models (e.g., Flatt's model, end of 20th century) did. Excess body fat storage is ultimately a problem of chronic positive energy balance mediated by a poor control of energy intake or/and a blunted total energy expenditure. Excess fat storage can stem from exogenous fat and to a more limited extent by nonfat substrates precursors transformed into body fat, mostly from carbohydrates, a process known as de novo lipogenesis. When considered over periods of weeks, months or years, total fat balance is closely related to energy balance. Over periods of days, the net change in fat balance is quantitatively limited as compared to the size of endogenous fat storage. The issues discussed in this article primarily include the stimulation of de novo lipogenesis after acute or prolonged CHO overfeeding and whether de novo lipogenesis is a risk factor for obesity development.  相似文献   

19.
The skin is an organ closely related to the endocrine system. The endocrine system has an important role in the skin development and its normal physiology. Skin, pilosebaceous unit, eccrine, and apocrine sweat glands have hormonal receptors and are targets of hormones. On the other hand, the skin synthesizes a variety of hormones and thus it may be considered as an endocrine organ. This article is an overview of the effects of some hormones on the skin.  相似文献   

20.
Mitochondrial reactive oxygen species (mROS) have emerged as signaling molecules in physiology primarily as a result of studies of uncoupling mechanisms in mitochondrial respiration. The discovery that this mechanism negatively regulates mROS generation in many cell types has drawn the attention of the scientific community to the pathological consequences of excess mROS production. From reports of the energetic fluxes in cells grown under normal conditions, the hypothesis that mROS are an integrated physiological signal of the metabolic status of the cell has emerged. Here, we consider recent studies that support this point of view in two key nutrient sensors of the body, beta cells and the hypothalamus, which are the main coordinators of endocrine and nervous controls of energy metabolism and adipose tissue, which is of paramount importance in controlling body weight and, therefore, the development of obesity and type 2 diabetes. In this context, finely balanced mROS production may be at the core of proper metabolic maintenance, and unbalanced mROS production, which is largely documented, might be an important trigger of metabolic disorders.  相似文献   

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