运动、医务监督综合处方对单纯性肥胖青少年女学生血瘦素、血脂、血糖、胰岛素的影响

目的观察有氧运动、医务监督综合减肥处方对单纯性肥胖青少年女学生血瘦素、血脂、血糖、胰岛素的影响。方法对单纯性肥胖青少年女学生采取有氧运动、合理饮食、心理矫正和医务监督等疗法,进行为期10个月减肥活动,测定试验前、中、后血瘦素及相关激素变化。结果单纯性肥胖青少年女学生血瘦素、胰岛素、血脂、血糖和胆固醇水平明显高于正常组,且瘦素水平与肥胖程度和胰岛素呈正相关,减肥后瘦素及相关激素水平明显下降(P均<0.05)。结论综合减肥处方能有效降低体质量,改善肥胖青少年女学生体内胰岛素和瘦素抵抗作用,从而起到调节异常内分泌代谢的作用。     

精神分裂症患儿利司培酮治疗前后血清瘦素和白细胞介素-1β变化的意义

目的探讨精神分裂症患儿利司培酮治疗前后血清瘦素和白细胞介素-1β(IL-1β)水平的变化及意义。方法观察组31例精神分裂症患儿,利司培酮治疗前和治疗8周后分别测量身高、体质量以计算体质量指数(BMI),用放射免疫法检测其空腹血清瘦素和IL-1β。选取31例健康儿童作为对照组。结果观察组治疗后BMI、血清瘦素水平均明显上升,与治疗前相比差异均有显著性(P均<0.05);观察组血清IL-1β水平在治疗前与对照组相比明显增高,治疗后明显下降,与治疗前相比差异有显著性(P<0.05)。结论首发精神分裂症患儿血清IL-1β水平明显升高,利司培酮治疗后易出现药源性肥胖,低IL-1β水平可能是瘦素抵抗的原因之一。     

Leptin and Its Emerging Role in Children and Adolescents

Leptin is an adipocyte-secreted hormone which plays a key role in energy homeostasis. Recent “proof of concept” studies involving leptin administration to humans support its critical role in regulating energy homeostasis, neuroendocrine and immune function as well as insulin resistance in states of energy/ caloric deprivation. Moreover, interventional studies in leptin deficient children and observational studies in normal girls and boys support a role for leptin as a permissive factor for the initiation of puberty in children. The potential clinical usefulness of leptin in several disease states in children and adolescents, including hypothalamic amenorrhea, eating disorders and syndromes of insulin resistance is still under investigation.     

Differential regulation of leptin receptor but not orexin in the hypothalamus of the lactating rat

During lactation, hypothalamic levels of neuropeptide Y (NPY) and agouti related protein (AGRP) mRNA are increased, while pro-opiomelanocortin (POMC) mRNA is decreased. Serum leptin levels are also decreased during lactation. These changes may underlie the large increases of both food and water intake that occur in concert with milk production. However, additional hypothalamic substances, such as the novel peptide, orexin, may be involved. In addition, in the presence of chronically suppressed levels of serum leptin, there may be a change in leptin receptor expression in the hypothalamus. The objectives of the present study were to determine if orexin and leptin receptor mRNA levels were changed during lactation. Rats were studied on dioestrus of the oestrous cycle or on day 10 postpartum (the lactating animals were suckling eight pups). Orexin mRNA levels in the lateral hypothalamus did not differ between dioestrus and lactation. There was a significant increase in leptin receptor mRNA levels in the supraoptic nucleus during lactation compared to dioestrus. Furthermore, leptin receptor protein, as determined by immunocytochemistry, was colocalized in virtually all vasopressin and oxytocin cells in the supraoptic nucleus. Lactating animals exhibited a decrease in leptin receptor mRNA in the ventromedial hypothalamic nucleus whereas no change was apparent in other hypothalamic areas compared to the dioestrus animals. These results demonstrate that changes in orexin do not appear to contribute to the increase in food intake during lactation. It is likely that the increases in NPY and ARGP, coupled with the decrease in POMC, are primarily responsible for sustaining the chronic hyperphagia of lactation. The changes observed in leptin receptor expression in the hypothalamus, along with the suppression of serum leptin levels, also suggest that the leptin signalling system may play a significant role in the regulation of food and water intake during lactation.     

Voluntary sucrose ingestion, like corticosterone replacement, prevents the metabolic deficits of adrenalectomy

We tested whether corticosterone replacement causes increased sucrose drinking in adrenalectomized (ADX) rats compared to sham-ADX (sham) rats. ADX rats given high doses of corticosterone drank as much sucrose as sham rats, whereas at three lower doses of corticosterone, drinking was similar between groups and was only approximately 40% of that ingested by shams. Compared to sham rats, ADX rats drinking saline, or saline and saccharin, gain weight more slowly, contain less white adipose tissue, and have higher sympathetic outflow as assessed by uncoupling protein content in brown adipose tissue. Allowing sucrose as well as saline to drink restored all of these variables to normal in ADX rats with no- or low-corticosterone. All endpoints from sucrose-drinking ADX rats with no-or low-corticosterone were indistinguishable from those in water-drinking shams. By contrast, sucrose-drinking ADX rats that were given high doses of corticosterone exhibited the usual catabolic effects of corticosterone on body weight gain and, unlike sucrose-drinking shams, were obese. We conclude that (i) high corticosterone stimulates the potability of sucrose and inhibits sympathetic stimulation of uncoupling protein; (ii) sucrose, without corticosterone, normalizes metabolic deficits in ADX rats probably through actions mediated both peripherally and by the central nervous system; and (iii) ADX rats have a distinct sucrose appetite.     

The effect of leptin on luteinizing hormone release is exerted in the zona incerta and mediated by melanin-concentrating hormone

The adipose hormone, leptin, not only restrains appetite, but also influences energy expenditure. One such influence is to promote sexual maturation and fertility. The neuromodulatory circuits that mediate this effect are not well known but the present study suggests that one mediator could be melanin-concentrating hormone (MCH). We show that the long-form receptor (Ob-Rb) is expressed in the zona incerta of the rat and that administration of leptin (both 0.5 microg and 1.0 microg/side) into this area of ovariectomized, oestrogen-primed rats stimulated the release of luteinizing hormone (LH) within 1 h, the effect enduring for a further 1 h. Injections of leptin into the arcuate nucleus induced a smaller, transient rise in LH while injections into the paraventricular and ventromedial nuclei were without effect. MCH neurones are present in the zona incerta and administration of this hormone into the medial preoptic area (mPOA) stimulates LH release, therefore we investigated the possibility that MCH might mediate this effect of leptin. An injection of MCH antiserum into mPOA prevented the rise in LH normally induced by leptin injected into the zona incerta. In addition, melanocortin receptor antagonists ([D-Arg8]ACTH(4-10) and [Ala6]ACTH(4-10)), previously shown to inhibit the stimulatory effect of MCH on LH release, also inhibited the effect of leptin. We propose that one route by which leptin may promote reproductive activity is by enhancing MCH release from fibres within the mPOA. Speculative mechanisms for the action of MCH include the following possibilities: MCH may be acting on the specific MCH receptor which in turn interacts with a melanocortin or melanocortin-like receptor; MCH may bind directly to one of the melanocortin receptors; or melanocortin antagonists may interact with the MCH receptor.     

沙格列汀联合二甲双胍对新诊断2型糖尿病患者血清炎症因子及胰岛β细胞功能的影响分析

将2型糖尿病患者共80例分为对照组(n=40)和观察组(n=40),对照组患者给予二甲双胍治疗,观察组患者给予沙格列汀联合二甲双胍治疗。两组患者治疗后空腹及餐后2小时血糖、肿瘤坏死因子-α(TNF-a)水平较治疗前均明显降低(P<0.05),可溶性类肿瘤坏死因子细胞凋亡弱诱导剂(sTWEAK)较治疗前明显升高(P<0.05),且对照组与观察组患者治疗后血糖控制指标及炎症因子间差异有显著性(P<0.05),且观察组患者的糖化血红蛋白达标率更高;两组患者治疗后胰岛素抵抗指数(HOMA-IR)水平均明显降低(P<0.05)而胰岛β细胞功能指数(HOMA-β)明显升高(P<0.05),且与对照组患者相比,观察组患者的上述指标变化更显著(P<0.05)。因此,沙格列汀联合二甲双胍可以纠正新诊断2型糖尿病患者炎症因子水平、改善胰岛β细胞功能,有效控制血糖。