骨骼的内分泌功能

既往认为骨骼是支持机体基本结构和参与运动及钙磷代谢的主要器官。近年发现组成骨骼的成骨细胞和破骨细胞能合成和分泌多种骨调节蛋白、生长因子、脂肪因子、炎症因子和心血管活性肽等多种生物活性物质,以旁/自分泌方式调节骨骼系统功能,并能通过血液循环远距分泌的方式,调节机体能量代谢、炎症反应和内分泌稳态等。     

脂肪组织蛋白质组学研究进展

脂肪组织不仅是机体的能量储存库,而且也是重要的内分泌器官。脂肪组织分泌多种激素和细胞因子,参与调节机体多种生理和病理过程。目前飞速发展的蛋白质组学技术,为深入研究脂肪发育的分子机制及其代谢紊乱发生的遗传机理提供了有力的工具。对蛋白质组学在脂肪组织中的研究进展进行了综述,为脂肪组织的发育调控及代谢疾病的治疗提供了新的思路。     

脂肪组织的免疫功能

脂肪组织不仅是能量的储备器官,也是一个重要的内分泌器官.它协助神经系统和其他内分泌器官维持机体的内平衡.近年来,一些研究表明脂肪组织与免疫反应有着密切的联系.人们发现脂肪细胞分泌的瘦素不仅调节机体的能量代谢和控制脂肪的积累,还参与调节单核细胞、巨噬细胞和淋巴细胞的免疫功能,是一种作用广泛的细胞因子.脂肪细胞分泌的其他因子如脂联素也有免疫调节作用.免疫刺激还会作用于淋巴结周围的脂肪组织,引起这些脂肪细胞发生脂解作用.脂肪组织与免疫系统的相互作用,进一步表明生命是由各系统组成的一个有机统一体.随着对这一领域的研究不断深入,可能为某些疾病的治疗提供新的途径.     

综述与专论: 运动调节骨源性因子改善阿尔茨海默病的机制

阿尔茨海默病 （Alzheimer’s disease， AD） 作为一种神经退行性疾病会引起中枢神经病变。骨骼和大脑的紧密联系揭示出骨骼和AD之间的内在关联。骨骼作为骨内分泌器官逐渐受到重视。骨骼可分泌骨源性因子（SOST、OCN、OPN）、生成小胶质样细胞以及骨髓干细胞，这些骨源性因子和来源于骨骼的细胞通过血脑屏障调节大脑的生理特性，改善AD的代谢过程。运动刺激骨骼内分泌功能，调节骨源性因子分泌和表达水平，最终延缓AD病理变化并改善AD认知功能水平。本文侧重于阐述骨源性因子对AD的改善作用，以及运动刺激骨骼内分泌改善AD过程的新方法和新视角，为脑骨交互研究提供新思路。     

补体系统及其在肝损伤再生中的作用

补体系统是机体免疫防御机制的重要组成部分,参与免疫识别和防御。近年来,系统研究发现补体除免疫调节外,还具有参与生殖发育、成骨、组织和器官再生等重要生理机能的作用。多项研究报道了补体活化和各种肝损伤／再生的关系,对此进行综述,以期促进对补体多样性功能的了解。     

骨骼肌的内分泌功能

长期以来,骨骼肌被认为是一种效应器官,接受神经和体液的调节。近年大量实验研究资料发现骨骼肌也具有分泌活性物质的功能,能表达、合成和分泌多种生物信号分子,包括调节肽、细胞因子和生长因子等,也是一种重要的内分泌器官。骨骼肌分泌的活性物质以旁分泌和／或自分泌方式调节骨骼肌的生长、代谢和运动功能;甚至以血液循环内分泌的方式调节机体远隔器官组织的功能。骨骼肌生成和分泌的活性物质在运动系统疾病和某些全身性疾病的发病中具有重要的作用。本文将对骨骼肌分泌的主要活性物质及其生理和病理生理学意义进行综述。     

对骨细胞生物学功能的最新认识

骨细胞长久以来都被看作是一种终末分化的、代谢隋性的、深埋在骨基质之中的占位细胞．并不具有重要的生理作用和功能。然而近些年的研究发现,骨细胞是一种活跃的多功能细胞,参与机体诸多生物学过程的调控。骨细胞的生物学功能可以大致归纳为以下六类：调节骨重建平衡、感知和转导力学刺激、参与机体的神经-内分泌调节、与肌肉组织有密切的相互作用、降解与合成骨基质及调控骨组织内储存的钙和其他生物活性物质。     

脂肪分泌组学的研究进展

分泌蛋白是由细胞主动运输到细胞外的一大类具有重要生物学功能的蛋白,主要参与细胞信号转导、细胞的增殖、分化及凋亡等多种生物学过程.细胞、组织、器官及个体分泌的所有蛋白称为分泌组.脂肪组织曾被认为只是机体内能量储藏的地方,但现在发现它还是体内最大的内分泌器官.近年来,由于蛋白质组学技术的快速发展,脂肪分泌组研究已成为脂肪生...     

脂肪因子与代谢综合征关系的研究进展

代谢综合症是一系列代谢和心血管功能失调的临床特征,包括中心性肥胖、高血压、血脂异常、高血糖及胰岛素抵抗等,其发病机制及如何预防及控制代谢综合症正日益成为目前的学术热点。目前已经公认,脂肪不仅是能量存储器官,也是一个重要的内分泌器官。脂肪组织分泌的生物活性分子被称为脂肪因子。近年来的研究表明,脂肪因子广泛参与肥胖、2型糖尿病、高血压病及心血管疾病等一系列代谢相关性疾病的病理生理过程。脂肪因子能通过介导一系列的信号转导通路,并广泛参与机体复杂的代谢平衡网络的调节。脂肪因子的失衡能导致机体发生对胰岛素敏感性改变等一系列的生物学反应,从而在肥胖和代谢综合症的病理过程中发挥重要的作用。本文综述了脂肪因子与代谢综合征的关系的研究进展。     

神经内分泌讲座（二）：———促甲状腺激素分泌的神经内分泌调节

甲状腺是人及动物体内十分重要的内分泌器官。它分泌的甲状腺激素调节机体的代谢、生长发育等过程。甲状腺的功能又受到下丘脑－腺垂体－甲状腺轴的调节,而下丘脑又受脑的其它部位的功能控制。因此,通过下丘脑的神经内分泌作用,将神经系统的活动与甲状腺的内分泌功能有...     

Neural regulation of bone remodeling: Identifying novel neural molecules and pathways between brain and bone

The metabolism and homeostasis of the skeletal system have historically been considered to be associated with the endocrine system. However, this view has been expanded with the recognition of several neural pathways playing important roles in the regulation of bone metabolism via central relays. In particular, bone metabolism and homeostasis have been reported to be precisely modulated by the central neural signaling. Initiated by the finding of leptin, the axis of neural regulation on bone expands rapidly. The semaphorin–plexin system plays an important role in the cross-talk between osteoclasts and osteoblasts; a complex system has also been identified and includes neuropeptide Y and cannabinoids. These findings facilitate our understanding of the central neuropeptides and neural factors in the modulation of bone metabolism and homeostasis, and these neuronal pathways also represent an area of research scenario that identifies the novel regulation between brain and bone. These regulatory mechanisms correlate with other homeostatic networks and demonstrate a more intricate and synergetic bone biology than previously envisioned. As such, this review summarizes the current knowledge of the neural regulation of bone metabolism and homeostasis, as well as its role in skeletal diseases and discusses the emerging challenges presented in this field.     

Endocrine functions of brain in adult and developing mammals

The main prerequisite for organism’s viability is the maintenance of the internal environment despite changes in the external environment, which is provided by the neuroendocrine control system. The key unit in this system is hypothalamus exerting endocrine effects on certain peripheral organs and anterior pituitary. Physiologically active substances of neuronal origin enter blood vessels in the neurohemal parts of hypothalamus where no blood-brain barrier exists. In other parts of the adult brain, the arrival of physiologically active substances is blocked by the blood-brain barrier. According to the generally accepted concept, the neuroendocrine system formation in ontogeny starts with the maturation of peripheral endocrine glands, which initially function autonomously and then are controlled by the anterior pituitary. The brain is engaged in neuroendocrine control after its maturation completes, which results in a closed control system typical of adult mammals. Since neurons start to secrete physiologically active substances soon after their formation and long before interneuronal connections are formed, these cells are thought to have an effect on brain development as inducers. Considering that there is no blood-brain barrier during this period, we proposed the hypothesis that the developing brain functions as a multipotent endocrine organ. This means that tens of physiologically active substances arrive from the brain to the systemic circulation and have an endocrine effect on the whole body development. Dopamine, serotonin, and gonadotropin-releasing hormone were selected as marker physiologically active substances of cerebral origin to test this hypothesis. In adult animals, they act as neurotransmitters or neuromodulators transmitting information from neuron to neuron as well as neurohormones arriving from the hypothalamus with portal blood to the anterior pituitary. Perinatal rats—before the blood-brain barrier is formed—proved to have equally high concentration of dopamine, serotonin, and gonadotropin-releasing hormone in the systemic circulation as in the adult portal system. After the brain-blood barrier is formed, the blood concentration of dopamine and gonadotropin-releasing hormone drops to zero, which indirectly confirms their cerebral origin. Moreover, the decrease in the blood concentration of dopamine, serotonin, and gonadotropin-releasing hormone before the brain-blood barrier formation after the microsurgical disruption of neurons that synthesize them or inhibition of dopamine and serotonin synthesis in the brain directly confirm their cerebral origin. Before the blood-brain barrier formation, dopamine, serotonin, gonadotropin-releasing hormone, and likely many other physiologically active substances of cerebral origin can have endocrine effects on peripheral target organs—anterior pituitary, gonads, kidney, heart, blood vessels, and the proper brain. Although the period of brain functioning as an endocrine organ is not long, it is crucial for the body development since physiologically active substances exert irreversible effects on the targets as morphogenetic factors during this period. Thus, the developing brain from the neuron formation to the establishment of the blood-brain barrier functions as a multipotent endocrine organ participating in endocrine control of the whole body development.     

多糖对肠道功能调节作用的研究进展

肠道是机体重要的消化器官,亦是共生微生物群的主要寄居场所,在维持机体正常生命活动如免疫和内分泌功能中发挥着重要作用。 肠道功能紊乱与疾病的发生以及发展过程密切相关。近年来,多项研究结果显示,多糖具有肠道功能调节作用,包括通过作用于肠道黏膜 参与机体免疫过程、保护肠道屏障结构和功能的完整性、调节肠道菌群组成以及刺激肠道内分泌。从伴随疾病过程中的肠道功能紊乱的角度, 对多糖调节肠道功能的作用机制进行综述。     

Cardiac endocrine function is an essential component of the homeostatic regulation network: physiological and clinical implications

The discovery of cardiac natriuretic hormones required a profound revision of the concept of heart function. The heart should no longer be considered only as a pump but rather as a multifunctional and interactive organ that is part of a complex network and active component of the integrated systems of the body. In this review, we first consider the cross-talk between endocrine and contractile function of the heart. Then, based on the existing literature, we propose the hypothesis that cardiac endocrine function is an essential component of the integrated systems of the body and thus plays a pivotal role in fluid, electrolyte, and hemodynamic homeostasis. We highlight those studies indicating how alterations in cardiac endocrine function can better explain the pathophysiology of cardiovascular diseases and, in particular of heart failure, in which several target organs develop a resistance to the biological action of cardiac natriuretic peptides. Finally, we emphasize the concept that a complete knowledge of the cardiac endocrine function and of its relation with other neurohormonal regulatory systems of the body is crucial to correctly interpret changes in circulating natriuretic hormones, especially the brain natriuretic peptide.     

骨骼的新认识——骨内分泌

骨骼被认为是一个动态结缔组织,具有重塑能力,以维持钙稳态和造血等功能。大量的研究显示,骨骼不仅作为结构支架,也作为内分泌器官调控代谢过程。除了传统的OPG、SOST、DKK等在骨形成、骨构成、骨重建以及骨稳态中扮演重要角色,骨骼还分泌特异性激素--骨钙素(osteocalcin, OCN)和成纤维细胞生长因子23(fibroblast growth factor 23, FGF23)。其中,骨钙素可促进β细胞增殖、胰岛素分泌、提高胰岛素敏感性,还可调节脂肪细胞、男性性腺内分泌活动和神经系统活性;成纤维细胞生长因子23通过对肾调节维持血磷内稳态。     

脂肪组织功能失调在动脉血栓相关疾病中的作用

肥胖与代谢综合征是传统心血管疾病的危险因素.多项临床研究表明,肥胖也会增加患血栓性疾病(如急性心肌梗死和脑卒中)的风险.脂肪组织与血小板反应性增加和高凝状态形成以及纤溶功能降低等存在着重要联系.脂肪组织还是一个高度活跃的内分泌器官,其表达和分泌具有重要功能的脂肪因子和脂质代谢物参与调控全身代谢.深入地了解脂肪组织的内分...     

A neuro (endo)crine regulation of bone remodeling

Bone remodeling is the normal physiologic process that is used by vertebrates to maintain a constant bone mass during the period bracketed by the end of puberty and the onset of gonadal failure in later life. Besides the well-characterized and critical process of local regulation of bone remodeling, achieved by autocrine and paracrine mechanisms, recent genetic studies have shown that there is a central control of bone formation, mediated by a neuroendocrine mechanism. This central regulation involves leptin, an adipocyte-secreted hormone that controls body weight, reproduction and bone remodeling, and which binds to and exerts its effect through the cells of the hypothalamic nuclei in the brain. This genetic result in mice is in line with clinical observations in humans and generates a whole new direction of research in bone physiology. BioEssays 22:970-975, 2000.     

Interactions between the immune and neuroendocrine systems: clinical implications

The endocrine and immune systems are interrelated via a bidirectional network in which hormones affect immune function and, in turn, immune responses are reflected in neuroendocrine changes. This bidirectional communication is possible because both systems share a common "chemical language" that results from a sharing of common ligands (hormones and cytokines) and their specific receptors. Cytokines are important partners in this crosstalk. They play a role in modulating the hypothalamo-pituitary-adrenal (HPA) axis responses at all three levels: the hypothalamus, the pituitary gland and the adrenals. Acute effects of cytokines are produced at the central nervous system level, particularly the hypothalamus, whereas pituitary and adrenal actions are slower and are probably involved during prolonged exposure to cytokines such as during chronic inflammation or infection. Several mechanisms have been proposed by which peripheral cytokines may gain access to the brain. They include an active transport through the blood-brain barrier, a passage at the circumventricular organ level, as well as a neuronal pathway through the vagal nerve. The immune-neuroendocrine interactions are involved in numerous physiological and pathophysiological conditions and the interactions with the HPA axis may represent a mechanism through which the immune system, by stimulating the production of glucocorticoids, avoids an overshoot of inflammatory response. They may also be involved in the state of hypogonadism, of hypothyroidism and growth inhibition which can occur during inflammatory and infectious diseases. The crosstalk between the immune and endocrine systems is important to homeostasis, since the interactions can produce various appropriate adaptative responses when homeostasis is threatened.     

蜜蜂脂肪体的形态和功能研究进展

脂肪体是昆虫体内的一种多功能器官,近似于脊椎动物的肝脏,分布于昆虫腹部、胸部甚至头部腔体中,以腹部脂肪体最为发达。蜜蜂脂肪体有外周脂肪体和围脏脂肪体两种类型,由营养细胞、尿酸盐细胞和绛色细胞组成。同其他昆虫中类似,脂肪体在蜜蜂的生命活动中扮演着重要的角色,其形态和功能随发育阶段、季节和劳动分工的变化而变化。脂肪体结构相对简单,但生理功能非常复杂。脂肪体最主要的功能是能量物质的储存和代谢,其不仅是蜜蜂营养物质(即脂质、碳水化合物和蛋白质)的中央储存库,而且是营养代谢的中间站,具有多种能量和物质相互转换的酶系,承担代谢水的供应并合成嘌呤和嘧啶及许多重要的蛋白质。同时,脂肪体是昆虫发育和行为调控过程中各种激素和营养信号的交换中心,脂肪体激素和营养信号参与调控蜜蜂脂肪体发育、营养物质代谢、生殖及劳动分工。脂肪体兼具能量储存和释放、生物合成和分解、营养感知调节、代谢信号整合、内分泌调节、免疫和解毒、磁场感受、提高抗寒能力、保护体腔内器官等多种功能。鉴于脂肪体的重要作用,蜜蜂脂肪体形态和功能的研究成果可以对昆虫营养信号通路的解析、蜂产品高产良种的选育和蜜蜂病害防治的研究提供参考和思路。