甘精胰岛素与瑞格列奈能互补

甘精胰岛素是一种较为理想的基础胰岛素，和其它胰岛素一样，主要作用是调节糖代谢，通过促进骨骼肌和脂肪等周围组织摄取葡萄糖、抑制肝糖元而降低血糖。同时，甘精胰岛素还具有抑制脂肪分解，抑制蛋白质水解及促进蛋白质合成作用，从而减少血糖来源，发挥有效降低血糖的作用。甘精胰岛素是一种长效胰岛素，经皮下注射后释放缓慢，继之吸收入血的过程也比较缓慢，     

创伤应激后的糖代谢

创伤应激后，机体原有糖代谢平衡紊乱，糖原分解加快，糖原合成减少，糖异生加强，无氧酵解增多，糖利用抑制。创伤早期血糖升高的主要原因是糖原分解，也可能与糖异生有关；当机体进入代谢起涨期后，糖原分解殆尽．糖原合成不足，此时血糖升高主要来源于糖异生，糖摄取利用障碍也可能是原因之一。本文主要从糖原分解与合成、糖异生、糖酵解、糖摄取等环节综述创伤应激后的糖代谢特点。     

防治妊娠期代谢综合征中改善胰岛素抵抗的研究进展

<正>胰岛素抵抗(insulin resistance,IR)是指机体对一定量胰岛素的生物学反应低于预计水平的一种现象,即胰岛素敏感细胞对胰岛素介导的葡萄糖摄取和利用的抵抗,它反映的是胰岛素的糖代谢效应。胰岛素的生理效应很广泛,包括介导葡萄糖摄取、氧化及贮存、促进蛋白质、脂肪合成、抑制糖原异生和脂肪分解等,对胰岛素敏感的靶器官是肝脏、     

必需微量元素在糖尿病营养治疗中的潜在重要性

无论Ｉ型和ＩＩ型糖尿病均存在机体组织中几种必需微量元素浓度的改变，其中某些变化与葡萄糖体内平衡失调有关，可通过适当补充微量营养素加以纠正。机体补充某些微量营养素后或许对糖代谢有改善作用，本文对这方面的经周密控制的动物实验和人体研究结果进行综述。     

葡萄糖酸铬对实验性糖尿病小鼠肝PAS反应的影响

应用PAS反应观察了葡萄糖酸铬治疗的四氧嘧啶性糖尿病小鼠肝糖原变化。实验Ⅰ组铬每日口服剂量为10μg/kg体重,实验Ⅱ组为5μg/kg体重,另设正常对照组及糖尿病对照组。实验周期为4周。结果实验组肝糖原明显增多,实验Ⅰ组更为明显。实验结果提示葡萄糖酸铬可能通过促进肝糖原的合成和周围组织中葡萄糖的利用起到抗糖尿病作用。     

中成药中芬氟拉明的液相色谱-质谱测定法

芬氟拉明能使下丘脑和间脑区释放5-羟色胺，并阻断5-羟色胺的再摄取，从而抑制食欲；能减少脂肪吸收、合成以及过多脂肪的积聚，促进周围脂肪的分解；还能加速外围组织对葡萄糖的摄取，降低血糖。我国规定中药中不允许添加此类西药。另外，目前，测定芬氟拉明没有国际标准，并用此方法对部分产品进行了测定。     

生长激素诱导的胰岛素抵抗研究进展

生长激素日益广泛地应用于外科临床，但在其使用过程中对机体糖代谢有显著的影响。本文就生长激素导致机体糖代谢异常、胰岛素抵抗的机制及可能采用的纠正进行了综述。     

运动强度及方式对葡萄糖摄取影响的分子机制研究进展

运动疗法作为2型糖尿病预防和治疗的重要手段,可明显改善包括骨骼肌与脂肪在内的外周组织对胰岛素的抵抗。运动能够促进骨骼肌对葡萄糖的摄取,改善糖耐量,提高胰岛素的敏感性。运动对胰岛素抵抗和葡萄糖摄取的影响与骨骼肌中相关信号传导通路的蛋白表达与活性增强有关。研究表明,运动强度可能是影响葡萄糖代谢相关信号通路活性的主要因素,本文主要针对不同运动强度及方式对葡萄糖摄取相关信号通路的分子机制进行概述,为有效在临床上进行运动疗法奠定理论基础。     

名词解释

69 [代谢综合征 (MS) ]是多种代谢成分异常聚集的病理状态 ,诸代谢异常成分的标准国际上未有统一 ,多数标准中代谢异常成分有 (1)腹部肥胖或超重。 (2 )动脉粥样硬化性血脂异常 ,高甘油三酯 (TG)、高血脂、低密度脂蛋白 胆固醇 (LDL C)增高及高密度脂蛋白 胆固醇(HDL C)低下。 (3)高血压。 (4)胰岛素抗抗 (IR)及 /或葡萄糖耐量异常等。70 [胰岛素抵抗 (IR) ]是指胰岛素在周围组织摄取和清除葡萄糖的作用减低 ,机体为维持正常血糖 ,胰岛 β细胞代偿性分泌胰岛素 ,使胰岛素增加 ,引起高胰岛素血症。71[糖耐量 ]机体处理葡萄糖的能力称…     

胆汁郁积的机理

一、肝细胞的胆汁分泌机理胆汁系由肝细胞通过毛细胆管分泌入胆道,此一分泌过程的障碍或胆道阻塞,则导致胆汁郁积。目前认为肝细胞摄取胆红素可能有两种方式,一是非结合胆红素白蛋白复合体到达肝血窦后迅速分离,非结合胆红素以非离子扩散方式经过肝细胞膜进入细胞内,再与细胞内特殊胞浆蛋白结合。另一种可能是肝细胞膜有特异性受体摄取胆红素,再进入细胞内与特殊胞浆蛋白结合。这种特殊胞浆蛋白已分离出来,命名为Y和Z蛋白,这两种蛋白在肝细胞摄取胆红素的过程中起重要作用。非结合胆红素在肝细胞内要与葡萄糖醛酸结合转变为结合胆红素后才能从胆道排出。正常人胆汁中的胆红素98～99％是结合的,主要是胆红素葡萄糖醛酯。结合的部位于肝脏微粒体中,胆红素与葡萄糖醛酸结合,要经过一系列酶的催化作     

Insulin sensitivity in septic cancer-bearing patients.

Resistance to insulin's effect on glucose metabolism is a well-documented phenomenon. The magnitude of resistance to insulin's antilipolytic action is usually less than the resistance to insulin's action on glucose metabolism. In sepsis, resistance to the antilipolytic effect of insulin may be more prominent than resistance to insulin's action on glucose metabolism. Therefore, free fatty acid (FFA) turnover, FFA concentration, glucose tissue uptake, and endogenous glucose production were measured in nine septic cancer-bearing patients and six healthy volunteers during a constant glucose load at two different insulin concentrations. During infusion of glucose alone, plasma insulin concentration in patients and control subjects were, respectively 33 +/- 7 mU/L and 23 +/- 4 mU/L. When plasma glucose was clamped at the low normal range these values were, respectively, 85 +/- 17 mU/L and 28 +/- 5 mU/L (p less than 0.05). Glucose tissue uptake and endogenous glucose production were not significantly different in patients and control subjects in both parts of the study. FFA turnover and FFA concentrations were significantly higher in the patients compared with the control subjects (p less than 0.001) in both parts of the study. It is concluded that in septic cancer-bearing patients, resistance to insulin's effect on FFA turnover is more pronounced than resistance to its inhibiting effect on endogenous glucose production and its stimulating effect on glucose tissue uptake.     

Metabolic actions of insulin in men and women

Insulin is an important regulator of glucose, lipid, and protein metabolism. It suppresses hepatic glucose and triglyceride production, inhibits adipose tissue lipolysis and whole-body and muscle proteolysis, and stimulates glucose uptake in muscle. In this review we discuss what is currently known about the control of substrate metabolism by insulin in men and women. The data available so far indicate that women are more sensitive to insulin with regards to glucose metabolism (both in the liver and in muscle), whereas there are no differences between men and women in insulin action on lipolysis. Potential differences exist in the regulation of plasma triglyceride concentration and protein metabolism by insulin and in changes in insulin action in response to stimuli (e.g., weight loss and exercise) that are known to alter insulin sensitivity. However, these areas have not been studied comprehensively enough to draw firm conclusions.     

Effets métaboliques différentiels des sucres

Main products of alimentary polysaccharides hydrolysis are glucose, fructose and galactose. These monosaccharides are absorbed by intestinal cells and delivered into the circulation via specific transporters. Glucose metabolism and its regulation in most important tissues of the body are briefly described and it is underlined that glucose is not only a fuel for the tissues but also an informative molecule which control glycolytic and lipogenic gene expression in liver and adipose tissue. The metabolism of galactose is briefly described. In contrast, the metabolism and the metabolic effects of fructose are detailled, underlining its beneficial effects at low concentration (hepatic glucose uptake) and its deletorious effects when consumed in excess (hepatic steatosis, insulin resistance, inflammation, hyperuricemia).     

Effects of vitamin B6 deficiency on liver, kidney, and adipose tissue enzymes associated with carbohydrate and lipid metabolism, and on glucose uptake by rat epididymal adipose tissue.

Adipose tissue and liver from vitamin B6-deficient rats have an increased lipogenic capacity. Whether this phenomenon is accompanied by changes in the activities of certain enzymes involved in the metabolism of carbohydrate and lipid, or by altered transport of glucose into adipocytes, has been studied. Five glycolytic enzymes (hexokinase, phosphoglucose isomerase, phosphofructokinase, aldolase, and pyruvate kinase), two pentose phosphate pathway enzymes (glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase), malic enzyme, and ATP citrate lyase were measured in the epididymal adipose tissue, livers and kidneys of vitamin B6-deficient and control rats. Vitamin B6 deficiency did not significantly affect the glycolytic enzyme levels in the tissues studied, or the dehydrogenases measured in adipose tissue and kidneys. Liver glucose-6-phosphate dehydrogenase, and adipose tissue and liver malic enzyme were significantly lowered in deficient rats compared to ad libitum and pair-fed controls. Adipose tissue and liver ATP citrate lyase activities were also significantly decreased by vitamin B6 deficiency. In the presence of insulin, the uptake of glucose and 3-O-methyl glucose, a non-metabolizable sugar, by fat pads from deficient rats was greater than uptake by fat pads from control rats. These observations suggest that the increased glucose utilization by adipose tissue and liver of vitamin B6-deficient rats is not directly related to changes in the enzymes studied, but in the case of adipose tissue, may be explained, at least in part, by enhanced glucose uptake.     

Ameliorating effects of L-carnitine on diabetic podocyte injury

High glucose levels can change podocyte gene expression and subsequently induce podocyte damage through altered glucose metabolism. l-Carnitine is known to play a beneficial role in diabetes; however, there are no studies on the effects of l-carnitine on podocyte alteration under high glucose conditions. This study investigated whether l-carnitine can attenuate diabetic podocyte injury through the prevention of loss of slit diaphragm proteins. The l-carnitine treatment group showed increased glucose uptakes compared to the control group, suggesting that glucose utilization in the podocytes was increased by l-carnitine. l-Carnitine treatment also prevented decreased mRNA expressions of nephrin and podocin in the high glucose-stimulated podocytes. However, mRNA expressions of CD2AP and α-actinin-4 were not significantly changed by the high glucose conditions. When these data are taken together, l-carnitine can increase glucose uptake in podocytes under high glucose conditions, and its mechanism may be at least partly related to the up-regulation of nephrin and podocin. Our results help clarify the beneficial effects of l-carnitine in diabetic nephropathy.     

Manipulation of the functional activity of the gut by dietary and other means (antibiotics/probiotics) in ruminants

The mucosa of the gut is some of the most metabolically active tissue in the body. This paper discusses the methodology used to assess enterocyte cell metabolism and nutrient uptake in the reticulorumen and small intestine of ruminant species. Metabolism of volatile fatty acids and glucose by this tissue may limit the availability of essential nutrients to peripheral tissues, and the extent to which this may vary between concentrate-based and forage-based diets is discussed. Factors that affect the development and expression of metabolite uptake by the enterocyte are considered in addition to the influence that manipulation of the microbial flora of the gut by the use of antibiotic growth promoters or probiotics may have upon this process. Data are presented to show that the use of antibiotic compounds in ruminant feeds can influence the rate of cell turnover in the small intestine and the rate of glucose uptake by isolated brush border vesicles.     

Physiological effects of caffeine in the rat: extracellular cyclic AMP status, growth pattern and glucose metabolism in adipose tissue

The authors investigated the effect of moderate caffeine intake on overall cyclic adenosine monophosphate (AMP) metabolism in the rat and its relationship to growth and glucose metabolism in adipose tissue. Male Sprague-Dawley weanling rats were divided into control and treatment groups. The latter received caffeine via drinking water (0.06 mg/ml H2O) during a 4-week period whereas controls received water only. At weekly intervals, urinary cyclic AMP excretion, food intake and weight gain were measured. Plasma cyclic AMP caffeine and glucose were determined at moment of death and in vitro lipogenesis and glycogen synthesis from [6-14C]glucose in epididymal adipose tissue were assayed. Although urinary cyclic AMP excretion was negatively correlated to caffeine intake during the 2nd week of the experiment, this did not reach significant levels, nor did this trend continue into the 4th week. Growth pattern and food efficiency were similar in both groups as were blood glucose and cyclic AMP values at moment of death. In vitro glycogen synthesis from [6-14C] glucose in adipose tissue showed a 40% increase, this parameter being positively correlated with plasma caffeine concentration. Glucose uptake and lipogenesis were unaltered in epididymal fat pads. These data suggest that regular intake of a moderate dose of caffeine leads to homeostasis of overall cyclic AMP metabolism and of selected physiological parameters under study. Alteration of glycogen synthesis in adipose tissue is discussed in relation to documented effects of caffeine ingestion on catecholamine secretion.     

Whole-body and adipose tissue glucose metabolism in response to short-term fasting in lean and obese women

BACKGROUND: Alterations in glucose metabolism during early fasting may be an important trigger of the hormonal and metabolic responses to fasting. OBJECTIVE: The purpose of this study was to determine whether glucose metabolism in response to brief starvation differs in lean and abdominally obese women. DESIGN: We evaluated whole-body glucose metabolism by use of stable-isotope tracer methods and glucose uptake in subcutaneous abdominal adipose tissue by use of arteriovenous balance in 7 lean [58 +/- 2 kg; body mass index (BMI; in kg/m(2)): 21 +/- 5] and 6 abdominally obese (96 +/- 2 kg; BMI: 36 +/- 1) women after 14 and 22 h of fasting. RESULTS: Between 14 and 22 h of fasting, whole-body glucose production and disposal declined in both groups (P < 0.05), but the reduction was 50% greater in lean than in obese women (P < 0.05). The decline in glucose uptake at 22 h of fasting was also lower in obese (0.11 +/- 0.04 micromol*100 g(-1) x min(-1)) than in lean (0.26 +/- 0.03 micromol x 100 g(-1) x min(-1)) women (P < 0.05). Decreases in plasma insulin and leptin concentrations between 14 and 22 h of fasting were also lower in obese than in lean women (insulin: 20 +/- 3% and 32 +/- 5%; leptin: 18 +/- 3% and 37 +/- 6%; both P < 0.05). CONCLUSIONS: The normal decline in glucose production and uptake that occurs during early fasting is blunted in women with abdominal obesity. These alterations in glucose metabolism are associated with a blunted decline in circulating concentrations of both insulin and leptin, which may explain some of the differences in the metabolic response to fasting observed between lean and abdominally obese persons.     

西布曲明对肥胖小鼠葡萄糖代谢的影响

目的:探讨西布曲明干预对高脂饮食诱导肥胖ICR小鼠葡萄糖代谢的影响。方法:高脂饲料喂养雄性ICR小鼠8周,建立肥胖小鼠模型。西布曲明(7 mg.kg-1.day-1)灌胃干预8周。然后行腹腔注射葡萄糖耐量试验(IPGTT)、胰岛素耐量试验(ITT)及microPET显像;测量小鼠的体重、脂肪组织重量及血生化指标;实时荧光定量RT-PCR方法检测肌肉组织中糖代谢相关基因的相对表达量。结果:西布曲明干预组小鼠体重显著减轻(P<0.05),皮下脂肪、内脏脂肪重量显著降低(P值均小于0.01),空腹血糖显著降低(P<0.05)。ITT试验中,西布曲明干预组小鼠各时间点血糖均低于对照组,差异在90分钟时有显著性(P<0.05);血糖的曲线下面积也显著低于对照组(P<0.05)。另外,西布曲明干预组小鼠的棕色脂肪摄取葡萄糖增多(P<0.05),但肌肉组织内糖代谢相关基因GLUT4、GYS1、HK2、PGC1、IRS1和MSTN的表达量没有显著改变。结论:西布曲明可以减轻小鼠体重,减少白色脂肪重量,增加棕色脂肪代谢能力并在一定程度上改善肥胖小鼠的胰岛素敏感性;西布曲明改善肥胖小鼠葡萄糖代谢的作用可能与肌肉组织中的GLUT4、GYS1、HK2、PGC1、IRS1和MSTN的表达水平无关。     

In vivo response to alpha(1)-adrenoreceptor stimulation in human white adipose tissue

OBJECTIVE: Recent studies in rats suggest an important effect of alpha(1)-adrenoreceptor stimulation on glucose uptake in white adipocytes. It is not known if alpha(1)-adrenoreceptor stimulation elicits similar metabolic effects in humans. RESEARCH METHODS AND PROCEDURES: Three microdialysis catheters in abdominal subcutaneous adipose tissue were perfused with 0.00, 0.01, 0.10, 1.00, and 10.00 microM isoproterenol, phenylephrine, or phenylephrine plus 100 microM propranolol. Dialysate concentrations of ethanol, glycerol, glucose, and lactate were measured for estimating blood flow (ethanol-dilution technique), lipolysis, and glycolysis, respectively. RESULTS: Phenylephrine, with or without propranolol, did not elicit a change in ethanol ratio. In contrast, the ethanol ratio decreased markedly with isoproterenol. Dialysate glucose concentration decreased with phenylephrine with and without propranolol and increased with isoproterenol. Phenylephrine caused a dose-dependent increase in dialysate glycerol concentration, with a maximal effect similar to that of isoproterenol. The effect was attenuated with propranolol. DISCUSSION: Our findings suggest that alpha(1)-adrenoreceptor stimulation by phenylephrine increases glucose uptake and metabolism in human abdominal adipose tissue. Furthermore, phenylephrine elicits a marked increase in lipolytic activity in white adipose tissue through beta-adrenoreceptor activation.