Cytokines in diseases of the endocrine system

Cytokines, the polypeptide mediators of the immune system, were shown to exert numerous actions on endocrine functions. Bidirectional links based on the sharing of mediators and receptors between the immune and neuroendocrine systems lead to the concept of the immune-neuroendocrine system that seems to constitute an important and sophisticated regulatory system in the homeostasis. Several cytokines were found to be involved in the pathogenesis of diseases of the endocrine system. In this brief review, we attempt to present a general outline of the local actions of cytokines on cells of endocrine organs with an emphasis on disease etiology (pituitary tumours and autoimmune endocrine diseases in particular).     

Stress and auto-immune endocrine diseases

Auto-immunity may occur in all endocrine tissues, with a particular prevalence in thyroid and pancreatic islets. The most demonstrative clinical expressions of this auto-immunity are Graves' disease and insulin-dependent diabetes. In the former, extensive data are available upon the immunological disorders seen in peripheral blood as well as in the thyroid itself. The predisposal profile of such diseases is quite well delineated (genetic markers in HLA system, organ-specific T suppressive deficiency). On the other hand, the mechanisms implicated in the onset of auto-immunity are still questioned, the classical viral infection being scarcely demonstrated. Clinical observation registers frequent stressful life events just before the onset of these diseases, but there are few convincing data in the literature. The recent findings on the close relations between the immune system and the central nervous system lead to conceive an actual psychoneuro-endocrine-immune axis. This axis might explain the eventual priming effect of stress in patients predisposed for an organ-specific auto-immunity.     

Coeliac disease in endocrine diseases of autoimmune origin

Abstract Coeliac disease (CD, sometimes called gluten-sensitive enteropathy or nontropical sprue) is an inflammatory disorder of the small intestine of autoimmune origin. It occurs in genetically predisposed people and is induced by a gluten protein, which is a component of wheat. The prevalence of histologically confirmed CD is estimated in screening studies of adults in the United States and Europe to be between 0.2% and 1.0%. The results of previous studies have indicated that the prevalence of CD is increased in patients with other autoimmune disorders such as: autoimmune thyroid diseases, type 1 diabetes mellitus, and Addison's disease. A coincidence of the above diseases constitutes autoimmune polyglandular syndrome (APS). The high prevalence of CD in APS is probably due to the common genetic predisposition to the coexistent autoimmune diseases. The majority of adult patients have the atypical or silent type of the disease. This is the main reason why CD so often goes undiagnosed or the diagnosis is delayed. CD, if undiagnosed and untreated, is associated with many medical disorders including haematological (anaemia), metabolical (osteopenia/osteoporosis), obstetric-gynaecological (infertility, spontaneous abortions, late puberty, early menopause), neurological (migraine, ataxia, epilepsy) as well as with an increased risk of malignancy, especially: enteropathy-associated T-cell lymphoma, small intestine adenocarcinoma, and oesophageal and oropharyngeal carcinomas. Early introduction of a gluten-free diet and lifelong adherence to this treatment decreases the risk of these complications.     

心血管系统内分泌研究进展

心脏和血管的各种细胞分泌的生物活性分子,在心血管系统的功能稳态中具有重要的调节作用。新的活性肽的发现不仅提高了人们对疾病的认识,而且以新的活性多肽为靶点防治心血管疾病可能具有广阔的临床应用前景。心血管系统分泌的活性多肽不仅种类繁多,而且功能复杂,其功能复杂性不仅与其受体和受体亚型的组织分布和表达有关,还与其基因转录的剪切方式有关。此外,活性多肽的功能多样性还与其前体来源的其他片段以及活性多肽对受体的多选择性有关。     

The gastrointestinal endocrine system

Gastrointestinal endocrinology is the study of the hormonal regulation of digestion. A number of characterized polypeptide hormones have been localized in specific gastroenteropancreatic endocrine cells. The fact that some of these hormones are also found in nerve and brain cells has given rise to the concept of a gut-brain axis. The functional capacities of these endocrine cells are determined by their anatomic location; the luminal exposure of gastroenteric endocrine cells represents an additional avenue for stimulation and release that is not open to pancreatic endocrine cells. Gastroenteropancreatic hormones regulate carbohydrate metabolism, gastric acid secretion, pancreatic exocrine and gallbladder function, gastrointestinal motility and blood flow. These important regulatory hormones may in turn be controlled by a series of gastroduodenal releasing hormones.Diabetes mellitus is the most important metabolic disorder related to a gastroenteropancreatic hormone imbalance. Most tumours producing these hormones are of pancreatic origin and produce a number of hormones; insulinomas and gastrinomas are detected readily because of the serious metabolic distrubances they cause. Other instances of altered circulating concentrations of these hormones result from rather than cause the disease.The challenge of future study is to determine if postprandial changes in the plasma concentrations of these hormones are sufficient or necessary, or both, for the control of digestion.     

X-ray semeiotics of cranial involvement in endocrine diseases]

The incidence and type of x-ray semeiotics of the skull involvement were studied in 703 patients with endocrine diseases (26 with acromegaly, 36 with hypercorticism, 104 with thyrotoxicosis, 23 with hypothyrosis, 98 with primary hyperparathyrosis, 302 with diabetes mellitus, 114 with hypogonadism). Craniogram analysis involved study of the thickness and structure of the vault bones, shape and size of the skull, status of the sutures, internal plate relief, changes of the base of the skull, of the sella turcica first of all, and facial bones. The characteristic x-ray symptom complexes of the involvement of the skull in some endocrine diseases were distinguished.     

趋化因子及趋化因子受体3在自身免疫疾病中的作用

人体在防御和清除入侵病原体等异物时,有一种使白细胞趋集的功能,有一些低分子量的物质能引起这种功能称之为趋化剂或趋化因子。这些小蛋白因其有定向细胞趋化作用而得名。经研究表明,趋化因子受体3（CXCR3）趋化因子可能在自身免疫内分泌疾病中起到致病作用。此外,血清中CXCR3趋化因子的判定可能辅助检测免疫活性。CXCR3和优先参与趋化Th1细胞的因子。该受体连接的趋化因子10（CXCL10）不仅参与白细胞募集,还诱导T细胞增殖的异源体和抗原的刺激。趋化因子10正调节Th1细胞产物并且负调节Th2细胞的产物。免疫反应纤维结合素（INF）产物可增强特异的炎症反应。当被激活或者发现炎症和肿瘤细胞后趋化因子受体3-B在内皮细胞中表达并且其结合的趋化因子10,趋化因子9和趋化因子11激活后产生血管抑制作用。     

Acute effects of acephate and methamidophos on acetylcholinesterase activity, endocrine system and amino acid concentrations in rats

Acute effects of acephate (Ace) and methamidophos (Met) on acetylcholinesterase activity, endocrine system and amino acid concentrations were studied in rats. The rats were injected intraperitoneally with Ace (500 mg/kg) or Met (5 mg/kg) and then sacrificed at 15 or 60 min after the injection (A15 and A60 for Ace and M15 and M60 for Met). The primary aim of this study was to determine whether the mammalian toxicity of Ace is solely due to its conversion to Met or the protection of Ace against Met-inhibited AChE is also an important factor. The second aim of this study was to study the effects of Ace and Met on the endocrine system and amino acid concentrations and whether or not these effects correlate with AChE inhibition and Met accumulation. The Ace or Met injected animals did not exhibit the signs of organophosphate (OP) poisoning within 15 min after the injection, but exhibited tremors at 45 min after the injection. Blood and brain AChE activity in A15 and M15 rats exhibited 55 to 75% inhibition while the enzyme activity in A60 and M60 rats exhibited 80 to 95% inhibition. Ace was metabolized to Met in rats both in vivo and in vitro. A 5 rats had significantly higher Met concentration in their liver, brain and adrenal glands compared to M 5 rats, and A60 rats had significantly higher Met concentrations in their blood, liver, brain and adrenal glands compared to M60 rats. Thus, tissue Met concentrations in Ace-treated rats were significantly higher than in Met-treated rats and the inhibition of AChE activity was not consistent with the amount of metabolically formed Met, supporting the hypothesis that the Ace protection plays a role in the overall toxicity. Ace and Met both impaired circulating blood hormone and amino acid concentrations in rats. The endocrine effects of Ace and Met differed from their cholinergic effects, and were not proportional to the amount of Met present in different tissues obtained from the treatment groups. Plasma ACTH concentration was elevated in M60 rats but not in A60 rats. Thus, Ace may indirectly protect the pituitary against the toxic effects of Met. Unlike plasma ACTH levels, serum corticosterone and aldosterone levels were elevated in both A60 and M60 rats. Therefore, the effect of Met on the adrenal cortex may be mediated by the pituitary gland, while the effect of Ace may be due to direct Ace-gland interaction. The decrease in the levels of some of the serum amino acids showed an increase in the energy demands in the treatment groups.     

Trauma and the endocrine system

The endocrine system may be the target of different types of trauma with varied consequences. The present article discusses trauma of the hypothalamic–pituitary axes, adrenal glands, gonads, and pancreas. In addition to changes in circulating hormone levels due to direct injury to these structures, there may be an endocrine response in the context of the stress caused by the trauma.     

Acute intestinal diseases in Northern Africa]

Analysis of morbidity of dysentery and the rest diarrheal affections according to the books for primary recording of patients at one of the large administrative territories of the Northern Africa showed that official statistics reflected only 1/13 of dysentery patients who applied for medical aid (18.2 and 236.3 per 100 000 residents, respectively). Morbidity index of the rest of diarrheal affections constituted 2424.5 per 100 000. The mean lethality in diarrhea affections (including dysentery) was 1.7%. The fact that in the examination of 439 persons who came in contact with the patients suffering from typhoid fever the causative agents of dysentery were isolated in 19 (4.3%) indicated their wide circulation among the population.     

Evolution of the reproductive endocrine system in chordates

The cephalochordate, amphioxus, is phylogenetically placed at the most primitive position in the chordate clade. Despite many studies on the endocrine system of amphioxus, definitive evidence has not been reported for the presence an endocrine system comparable to the pituitary-gonadal axis, which is important in the regulation of reproduction in vertebrates. Recent genome analyses in the amphioxus, Branchiostoma floridae, showed that it does not have any pituitary hormone genes except the thyrostimulin gene. Thyrostimulin is a heterodimeric glycoprotein hormone consisting of α and β subunits, and is present in various organs of vertebrates. Analyses of a phylogenetic tree and a synteny suggest that amphioxus' thyrostimulin is an ancestral type of the glycoprotein hormones in chordates. In addition, genes for sex steroidogenic enzymes belonging to the CYP family were found in the genome sequences. The conversion pathway of sex steroids from cholesterol to estrogen, androgen, and major sex steroids was also identified in the gonads of amphioxus in vitro. Furthermore, we demonstrated the expression of genes encoding thyrostimulin and sex steroidogenic enzymes by an in situ hybridization technique. Here, we discuss the evolution of hormones and reproductive functions in the neuroendocrine control system of chordates.     

Electromagnetic fields and human endocrine system

Extremely low frequency electromagnetic fields (ELF EMF) are commonly present in daily life all over the world. Moreover, EMF are used in the physiotherapy of many diseases because of their beneficial effects. There is widespread public concern that EMF may have potential consequences for human health. Although experimental animal studies indicate that EMF may influence secretion of some hormones, the data on the effects of EMF on human endocrine system are scarce. Most of the results concentrate on influence of EMF on secretion of melatonin. In this review, the data on the influence of EMF on human endocrine system are briefly presented and discussed.