The vascular endothelium plays a role in insulin action

The endocrine system relies on the vasculature for delivery of hormones throughout the body, and the capillary microvasculature is the site where the hormones cross from the blood into the target tissue. Once considered an inert wall, various studies have now highlighted the functions of the capillary endothelium to regulate transport and therefore affect or maintain the interstitial environment. The role of the capillary may be clear in areas where there is a continuous endothelium, yet there also appears to be a role of endothelial cells in tissues with a sinusoidal structure. Here we focused on the most common endocrine disorder, diabetes, and several of the target organs associated with the disease, including skeletal muscle, liver and pancreas. However, it is important to note that the ability of hormones to cross the endothelium to reach their target tissue is a component of all endocrine functions. It is also a consideration in organs throughout the body and may have greater impact for larger hormones with target tissues containing a continuous endothelium. We noted that the blood levels do not always equal interstitial levels, which is what the cells are exposed to, and discussed how this may change in diseases such as obesity and insulin resistance. The capillary endothelium is, therefore, an essential and understudied aspect of endocrinology and metabolism that can be altered in disease, which may be an appropriate target for treatment.     

The good,the bad,and the ugly facets of insulin resistance

Insulin is a potent anabolic hormone, and binding to its receptor activates downstream intracellular signaling pathways that regulate the nutrient metabolism, fluid homeostasis, growth, ionic transport, maintenance of vascular tone, and other functions. Insulin resistance (IR) is a condition characterized by subnormal cellular response to physiological levels of insulin. The IR is divided into three types (prereceptor, receptor, and postreceptor) based on the site of pathology. Beta cells attempt to overcome the IR by increasing the release of insulin, leading to hyperinsulinemia. IR is the predisposing factor for many metabolic and cardiovascular disorders. From the evolutionary perspective, the presence of IR offers a survival advantage in the face of starvation or stress. In this brief review, we discuss the different facets of insulin resistance and appraise the readers about the hitherto neglected beneficial advantages.     

黄芪丹参对多囊卵巢综合征大鼠雄激素/胰岛素受体表达影响的研究

目的：研究黄芪联合丹参对多囊卵巢综合征（PCOS）模型大鼠雄激素(AR)及胰岛素受体（INSR）表达的影响。方法：通过对大鼠注射外源性雄激素建立高雄激素无排卵模型，将建模成功的大鼠随机分为黄芪组、丹参组、黄芪＋丹参联合组以及模型组，每组10只，分别以黄芪、丹参、黄芪＋丹参联合用药行不同干预治疗，模型组用生理盐水灌胃。比较各组大鼠血清雄激素、胰岛素水平；卵巢AR、INSR mRNA及蛋白水平。结果：1）与模型组比较，黄芪组血清睾酮水平明显下降，丹参组血清胰岛素水平明显下降；联合组血清睾酮及胰岛素水平均明显下降。2）与模型组比较，黄芪组INSR蛋白水平明显下降，丹参组INSR蛋白水平明显上升；黄芪＋丹参联合组AR蛋白水平明显下降，同时INSR蛋白水平明显升高。3）与模型组比较，黄芪组AR mRNA水平明显下降，丹参组INSR mRNA水平明显上升；黄芪＋丹参联合组AR mRNA水平明显下降，同时卵巢INSR mRNA水平明显升高。结论：黄芪可改善PCOS的高雄激素状态，丹参可改善PCOS的高胰岛素状态，联合用药兼具抗雄激素及降低胰岛素的作用，AR、INSR表达的改变是其可能的作用机制之一。     

Resistant Starch Content in Foods Commonly Consumed in the United States: A Narrative Review

Resistant starch (RS; types 1 to 5) cannot be digested in the small intestine and thus enters the colon intact, with some types capable of being fermented by gut microbes. As a fiber, types 1, 2, 3, and 5 are found naturally in foods, while types 2, 3, and 4 can be added to foods as a functional ingredient. This narrative review identifies RS content in whole foods commonly consumed in the United States. Scientific databases (n=3) were searched by two independent researchers. Ninety-four peer-reviewed articles published between 1982 and September 2018 were selected in which the RS was quantified and the food preparation method before analysis was suitable for consumption. The RS from each food item was adjusted for moisture if the RS value was provided as percent dry weight. Each food item was entered into a database according to food category, where the weighted mean±weighted standard deviation was calculated. The range of RS values and overall sample size for each food category were identified. Breads, breakfast cereals, snack foods, bananas and plantains, grains, pasta, rice, legumes, and potatoes contain RS. Foods that have been cooked then chilled have higher RS than cooked foods. Foods with higher amylose concentrations have higher RS than native varieties. The data from this database will serve as a resource for health practitioners to educate and support patients and clients interested in increasing their intake of RS-rich foods and for researchers to formulate dietary interventions with RS foods and examine associated health outcomes.     

Variations in insulin requirements can be an early indicator of sepsis in burn patients

IntroductionA >25% increase in daily insulin dosing is suggestive of possible sepsis in burn patients, however, no conclusive evidence is available regarding the time point at which insulin dosing begins to increase. The purpose of this study is to determine the exact time point at which the insulin requirement increases among non-diabetic burn patients with sepsis.MethodsA retrospective chart review in non-diabetic burn patients with ≥20% total body surface area burned (TBSA) during 2010–2018 who received a blood culture for suspected sepsis. Absolute insulin dosing at intervals (0, 24, 48, 72, and 96 h prior to blood culture) were Box–Cox transformed and compared vs.?96 h reference using mixed-effects models accounting for within-patient dependencies.ResultsFifty-eight patients (84% males, age 44 ± 17 years, TBSA% 49 ± 17.5) were included. When cube root of daily insulin dosing was regressed on each time point in a mixed-effects model, statistically significant increase in insulin dosing compared to baseline was observed for ?48 (p = 0.018), ?24 (p = 0.011), and 0 h (p = 0.008).ConclusionDaily insulin dosing increases 48 h prior to development of other clinical signs of sepsis and can be used as a sensitive early marker.     

脂联素对高脂饮食诱导的胰岛素抵抗子宫内膜癌裸鼠移植瘤生长的影响

目的 探讨脂联素对高脂饮食诱导裸鼠胰岛素抵抗子宫内膜癌移植瘤生长的影响。方法 40只裸鼠随机分成高脂组和普食组，每组20只，分别喂养高脂饲料（high-fat diet，HFD）和普通饲料（normal diet，ND），10周后测定裸鼠空腹血糖（fasting blood glucose，FBG）和空腹血胰岛素（fasting serum insulin，FINS）水平，计算胰岛素抵抗指数（HOMA-IR），建立胰岛素抵抗裸鼠模型。第11周接种子宫内膜癌HEC-1B细胞，待瘤体长至0.5 cm时，两组随机选取10只裸鼠腹腔注射脂联素（adiponectin，APN）分为HFD+APN组、ND+APN组；其余裸鼠分别注射0.9%氯化钠分为HFD组、ND组；14周后，测定各组血糖和血脂的代谢情况。结果 高脂组裸鼠10周后的平均体重、体长、FBG、FINS、HOMA-IR均大于普食组，糖耐量试验和胰岛素耐量试验结果显示血糖水平亦高于普食组（均P＜0.05）；接种子宫内膜癌HEC-1B细胞后均成瘤，建模成功。HFD+APN组和ND+APN组移植瘤平均重量和体积增长速度均分别低于HFD组和ND组（均P<0.05）。HFD组和HFD+APN组14周后的FINS、HOMA-IR、TC和TG均较ND组和ND+APN明显升高（均P<0.01），且HFD组明显高于HFD+APN组（均P<0.01）；HFD+APN组的血脂联素水平低于ND+APN组（P<0.01），HFD组则低于ND组（P<0.05）。结论 脂联素可改善高脂饮食导致的胰岛素抵抗，抑制子宫内膜癌移植瘤生长。     

多囊卵巢综合征与相关微小RNA的研究进展

微小RNA(mi RNAs)是一组小分子非编码RNA,在转录后水平调控基因的表达。mi RNAs水平与糖尿病、胰岛素抵抗相关;多囊卵巢综合征(PCOS)患者外周血以及卵泡液中存在某些mi RNAs,提示mi RNAs可能作为PCOS相关的潜在生物标志物。研究发现,PCOS肥胖患者血清mi R-21、mi R-27b、mi R-103和mi R-155这4种mi RNAs的表达明显增加;而mi R-222、mi R-146a和mi R-30c这3种mi RNAs具有作为PCOS的血清生物标志物的某种可能性。卵泡液表达丰富的成熟mi RNAs,PCOS患者卵泡液中mi R-132和mi R-320表达显著低水平;mi R-224、mi R-376a和mi R-143这3种mi RNAs也可能作为PCOS病理生理机制研究的靶标。由于PCOS的异质性,不同研究得到的mi RNAs表达谱也不完全相同,所以对与PCOS相关的mi RNAs尚需进一步研究。     

Non alcoholic fatty liver disease and risk of incident diabetes in subjects who are not obese

Background and aims

It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.