高脂饲料诱导的大鼠胰岛素抵抗及其与血清瘦素的关系

摄入大量脂肪被认为是胰岛素抵抗（insulin resistance,IR)形成的一个主要因素，本工作根据Storlien LH的配方制作高脂饲料，分别喂饲成年雄性SD大鼠30d和／或60d，用Kraegen EW方法建立正糖钳技术评估IR，观察IR形成和发展过程中基础血清瘦素和胰岛素刺激下血清瘦素的变化。结果喂饲大鼠高脂饲料30d形成IR，其血糖，血清瘦素水平，肩胛区脂肪、肾周脂肪、附睾脂肪垫重量均较对照组显著升高（均P＜0．01），但血清胰岛素水平与对照组比较无差别；喂饲大鼠高脂饲料60d,IR程度和高血糖水平与30d高脂组仍一样，血清瘦素水平和三处脂肪重量进一步升高（P＜0．001和0．01），出现高胰岛素血症（P＜0．05）；但喂饲高脂30和60天动物体重增长和正糖钳实验中灌流胰岛素2h后的血清瘦素水平与对照组无差别。结果：提示高脂饲料可诱导正常成年大鼠形成IR，体脂增高，高血糖，高瘦素血症是这类IR大鼠的特征，而高瘦素血症可能是IR形成的原因，而高胰岛素血症是IR的结果。     

高脂饮食诱发血糖升高的动物模型中瘦素与胰岛素变化的关系

高脂饲料喂养大鼠,诱发胰岛素抵抗形成血糖升高,以研究瘦素与糖尿病的关系。将大鼠分为正常和高脂饲料喂养组,于喂养前及喂养30、60d时测血糖、瘦素与胰岛素水平,行高胰岛素正常血糖钳夹试验,最后分离分离脂肪称重。结果：高脂饮食组具有明显的胰岛素抵抗,有50％血糖升至8．3mmol/L以上;形成糖尿病的大鼠体重与对照组无明显区别;高脂饮食组瘦素与胰岛素水平与对照组比较有明显差异;所有大鼠瘦素水平与体重、胰岛素、血糖均呈正相关。结论：（1）高脂饮食是导致胰岛素抵抗形成糖尿病的诱因之一;（2）体脂含量与糖尿病正相关;（3）瘦素抵抗与胰岛素抵抗形成糖尿病的发病机制可能有关;（4）瘦素水平随着鼠龄的增加而增高,且参与体重的调节。     

瘦素抵抗的免疫调节作用及其与肿瘤发生的关系

瘦素是一种内分泌激素,与受体结合后发挥调节食欲、能量代谢、生殖和造血等多种生物学作用.瘦素抵抗与肿瘤发生发展密切相关,除对肿瘤细胞的增殖及凋亡等发挥作用外,还参与调节肿瘤局部微环境中多种免疫细胞的数目与功能,通过调控抗肿瘤免疫活性参与肿瘤发生发展.目前已发现瘦素抵抗的免疫调节作用在多种类型肿瘤中发挥功能,对肿瘤的诊断与防治具有重要意义.     

Obesity, insulin resistance and cancer risk

Obesity is a known cause of metabolic syndrome which includes Type II diabetes, hypertension, and dyslipidemia. It is well documented that insulin resistance contributes to the mortality and the incidence of metabolic syndromes including central obesity, dyslipidemia, hyperglycemia and hypertension. Both obesity and diabetes are emerging topics for researchers to consider as having a possible causal association with cancer since the two factors have been viewed as risk factors for cancer. The present paper introduced the hypothesis of a possible causal relationship between obesity, insulin resistance and cancer and reviews relevant existing studies in this area. More efforts and studies are needed to clarify the mechanisms and the common risk factors which might be incorporated into interventions to prevent cancer and cardiovascular diseases as top causes of death.     

子痫前期患者血清内脂素、肿瘤坏死因子α水平与胰岛素抵抗的相关性

目的:探讨子痫前期患者血清内脂素及肿瘤坏死因子-α(TNF-α)与胰岛素抵抗(IR)的关系。方法:根据子痫前期分类标准选取重度子痫前期患者30例、轻度子痫前期患者30例及正常孕妇40例。采用酶联免疫吸附试验(ELISA)法检测孕妇血清内脂素和TNF-α浓度,血浆葡萄糖氧化酶法测定空腹血糖(FBG),放射免疫法测定空腹胰岛素(FIns),全自动生化分析仪测定血浆甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)水平。通过计算平均动脉压(MAP)、体质量指数(BMI)和胰岛素抵抗指数(HOMA-IR),分析子痫前期患者血清内脂素、TNF-α水平与IR的关系。结果:重度、轻度子痫前期患者的血清内脂素和TNF-α浓度低于正常孕妇(P0.05),且重度子痫前期患者的血清内脂素和TNF-α浓度低于轻度子痫前期患者(P0.05);血清内脂素与TNF-α、HDL-C呈正相关(P0.05),与MAP、FIns呈负相关(P0.05);血清TNF-α与HDL-C呈正相关(P0.05),与BMI、TG、MAP、FIns呈负相关(P0.05)。多元逐步线性回归分析显示,FBG、FIns和HOMA-IR是影响血清内脂素及TNF-α水平的相关因素。结论:子痫前期患者血清内脂素、TNF-α水平与IR密切相关。     

多种脂源性细胞因子与2型糖尿病患者胰岛素抵抗相关

目的探讨2型糖尿病(T2DM)患者多种脂源性细胞因子与胰岛素抵抗作用关系。方法选择T2DM患者40例,根据BMI水平分为每20例为1组的obesity组和non-obesity组及正常对照组20人,检测血清空腹胰岛素(FINs)、空腹血糖(FPG)、血浆脂质(TG、TC、LDL、HDL)、脂联素(APN)、C1q/TNF相关蛋白3(CTRP3)、瘦素(leptin)及肿瘤坏死因子(TNF-α)等指标,根据HOMA公式,计算HOMA-AR并分析各指标之间相关性。结果 1)与正常对照组比较,T2DM组血清APN和CTRP3水平明显降低,leptin和TNF-α水平升高;与non-obesity组比较,obesity组APN和CTRP3的水平明显降低(P0.05或P0.01),leptin水平升高(P0.05);2)相关分析发现,APN浓度与年龄、BMI、FPG、TC、TG、LDL、FINs和HOMA-IR呈负相关(P0.05);CTRP3与FPG、FINs和HOMA-AR呈负相关(P0.05),与TG呈正相关(P0.05);leptin与FPG呈负相关(P0.05);TNF-α与FPG呈正相关(P0.05)。结论2型糖尿病患者血清中低APN、CTRP3和高leptin水平与肥胖和HOMA-IR密切相关可能是发病因子,其中FPG和TG作为独立因子,可作为评价胰岛素抵抗程度的新的敏感指标。     

Follicular hyperandrogenism and insulin resistance in polycystic ovary syndrome patients with normal circulating testosterone levels

Polycystic ovary syndrome (PCOS) is a common reproductive disease with high heterogeneity. The role of excess androgen in PCOS etiology remains disputed, since around 20%–50% of PCOS women do not display hyperandrogenemia. The microenvironment of the ovary critically influences follicular development. In the present study, we assessed the role of androgen in PCOS by investigating whether excessive follicular fluid androgen was present in PCOS patients with normal serum androgen levels and influenced by follicular fluid insulin resistance (IR). Follicular fluid samples of 105 women with PCOS and 105 controls were collected. Levels of steroid hormones, glucose and insulin in the follicular fluid were examined and compared with data from serum biochemistry tests. We found that 64.9% (63/97) of PCOS patients with normal serum androgen levels displayed abnormally high follicular fluid androgen level. The follicular fluid androgen level was positively correlated with follicular fluid IR within a certain range and follicular fluid estrogen-to-testosterone (E2/T) ratio was significantly reduced in these patients. These results indicated that there existed a subgroup of PCOS patients who displayed excessive follicular fluid androgen and IR despite their normal circulating testosterone (T) levels. Our study highlights the importance of ovary hyperandrogenism and IR in the etiology of PCOS.     

新生儿血清瘦素水平变化与胰岛素和生长激素关系的研究

目的　探讨新生儿血清瘦素来源及其与胰岛素和生长激素的关系。方法　采用放射免疫法检测 80例新生儿静脉血和脐血瘦素水平 ,根据不同胎龄新生儿出生体重值分为大于胎龄儿 (LGA)组 2 8例 ,适于胎龄儿 (AGA)组 36例 ,小于胎龄儿 (SGA)组 16例 ;采用Rohrer′s指数 =出生体重 (g)× 10 0 /身长 (cm) 3 估测新生儿营养状态。结果　早产儿血清瘦素水平明显低于足月儿 (0 6 6± 1 0 3ng/mlvs 3 5 9± 2 16ng/ml,P <0 0 1) ;AGA儿血清瘦素水平 (3 0 6± 0 96ng/m1)明显低于LGA儿(4 0 3± 2 2 2ng/m1) ,而高于SGA儿 (1 13± 1 98ng/m1) ;足月新生儿血清瘦素水平与Rohrer′s指数、新生儿体重、胎龄 ,血清胰岛素、生长激素水平呈显著正相关。结论　新生儿体内瘦素主要来源于自身脂肪组织 ,它反映新生儿的生长营养状态 ,推测瘦素可能通过胰岛素、生长激素共同调节新生儿的生长发育 ,在胎儿和新生儿生长发育中起重要作用。     

Surgical outcome of synchronous second primary cancer in patients with gastric cancer

PURPOSE: In order to improve the likelihood of curative and safe gastric surgery, this study investigated the clinical features and surgical outcomes of gastric cancer with a synchronous cancer. PATIENTS AND METHODS: The clinicopathological data of 10,090 gastric cancer patients at Samsung Medical Center from September 1994 to December 2006 were retrospectively analyzed. Of them, 90 patients with gastric cancer and a synchronous second primary cancer underwent simultaneous surgery for gastric cancer and second primary cancer. The clinicopathological characteristics of the patients, surgical outcome, and prognosis were examined. RESULTS: The most common synchronous second primary cancer was colorectal cancer (37 patients), followed by hepatocellular carcinoma (13 patients), renal cell carcinoma (11 patients), and pancreatic carcinoma (5 patients). The incidence of a second primary cancer in the gastric cancer patients was higher than the incidence in the general population. Stage I gastric cancer patients had more synchronous cancers than stage II patients (59 vs. 31). Postoperative complications were encountered in 7 patients. Four patients underwent reoperation. Two patients died from hepatic failure and leakage of esophagojejunal anastomosis. The 5-year survival rate of stage I and II gastric cancer was 61% and 39%, respectively. CONCLUSION: Since gastric cancer patients with a synchronous second primary cancer are not rare, the possibility of synchronous cancers in gastric cancer patients should be considered. The prognosis of early stage gastric cancer patients with a synchronous second primary cancer was influenced more by the presence of the second primary cancer than by the gastric cancer itself.     

胃癌患者血清Gas、leptin测定的临床意义

目的:探讨了胃癌患者血清胃泌素(Gas)、瘦素(leptin)水平的变化及意义.方法:应用放射免疫分析测定了32例胃癌患者血清中Gas、leptin水平的变化,并与35例正常健康人作比较.结果:胃癌患者血清Gas和leptin水平非常显著地高于正常人组(P＜0.01)且两者呈明显的正相关.结论:检测胃癌患者血清Gas、leptin水平的变化对疾病的预后观察具有重要的临床价值.     

Serum leptin and adiponectin levels and their association with allergic sensitization

Background: Obesity and respiratory allergies have increased in parallel in industrialized countries. We have recently shown an association between obesity and allergic sensitization whereby obesity diminished the protective effect of childhood farm contact. Objective: To assess whether taking obesity into account allergic sensitization is associated with adipokine levels in blood and whether this effect is modified by childhood farm contact. Methods: Serum samples of 231 adult participants (age 18–45 years) of the Lower Saxony Lung Study were analysed for leptin and adiponectin by ELISA. Subjects were elected to represent equal‐sized groups with respect to obesity (<30 vs≥30 kg/m²), childhood farm contact, specific IgE to ubiquitous allergens and sex. Multiple logistic regression models were adjusted for potential confounders. Results: Leptin levels were positively related to the prevalence of sensitization (highest vs lowest quartile odds ratio 6.7, 95% confidence interval 2.0–22.4). For adiponectin levels, a weak, not statistically significant inverse association with sensitization was shown (highest vs lowest quartile 0.4, 0.2–1.1). The association between leptin and sensitization appeared to be more pronounced in subjects with farm contact; however, the effect modification was not statistically significant. Conclusion: These findings suggest that adipokines might be involved in the causal pathway between obesity and allergic sensitization.     

Growth hormone secretion is impaired but not related to insulin sensitivity in non-obese patients with polycystic ovary syndrome

BACKGROUND: The aim of the study was to elucidate the relationship between growth hormone (GH) secretion and insulin resistance in polycystic ovary syndrome (PCOS) patients. In order to exclude the influence of obesity on these parameters, only non-obese PCOS patients were studied. METHODS: Eleven PCOS patients and 11 controls with a body mass index (BMI) 相似文献   

Evidence of subpopulations with different levels of insulin resistance in women with polycystic ovary syndrome

BACKGROUND: Polycystic ovary syndrome (PCOS) is non-uniformly associated with insulin resistance (IR). We examined IR in women with PCOS. METHODS: Sixty-nine PCOS women were subjected to the insulin suppression test (IST) to determine their steady-state plasma glucose (SSPG) as a direct measure of insulin sensitivity. RESULTS: SSPG exhibited a multimodal distribution suggesting the existence of subpopulations. The heterogeneous distribution of plasma glucose at 180 min (P = 0.011), with three modes, suggested differences in the plasma glucose level trajectories during the IST. Hence, the population was separated into three groups: (i) (n = 33), subjects with SSPG < or = 152.5 mg/dl, corresponding to the first to fifth deciles; (ii) (n = 29), subjects in the interval 152.5 mg/dl < SSPG < or = 300 mg/dl; (iii) (n = 7), subjects with SSPG > 300 mg/dl, corresponding to the tenth decile. Plasma glucose distributions at 180 min showed differences in their mean values and ranges among groups (P < 0.0001). The trajectories of the groups differed significantly during the IST (P < 0.0001). CONCLUSIONS: insulin sensitivity in our patients exhibited a discontinuous distribution, implying that PCOS is a heterogeneous disorder possessing subpopulations regarding IR.     

Associations of single nucleotide polymorphisms in the adiponectin gene with adiponectin levels and cardio-metabolic risk factors in patients with cancer

Objectives: The aims of this study are to (1) study the influence of polymorphisms in adiponectin gene on adiponectin levels and potential associations with breast, prostate and colon cancer; (2) investigate the associations of adiponectin levels with other adipokines and breast, prostate and colon cancers. Subjects: We measured fasting adiponectin, leptin, insulin, Sex steroids in 132 (66 females, 66 males) cancer patients and 68 age and sex matched apparently healthy subjects. Body Mass Index (BMI) and waist circumference were used as indices of obesity. Insulin Resistance was assessed using Homeostasis Model Assessment (HOMA). Three single nucleotide polymorphisms (SNP rs182052 (G-10066-A), SNP rs1501299 (276G > T), SNP rs224176 (45T > G) in adiponectin gene were studied using Real Time Polymerase Chain Reaction. Results: GG genotype of SNP rs1501299 was significantly associated with higher levels of adiponectin (OR=1.2, 95%CI(1.03–1.3), p = 0.02); breast (OR=8.6, 95%CI(1.03–71), p = 0.04), colon cancers (OR= 12, 95%CI(1.2–115), p = 0.03). GT genotype was also associated significantly with colon cancer (OR=2.6, 95%CI (1.1–6), p = 0.03). However SNP rs224176 was associated with only breast cancer. Conclusion: Our results demonstrate that adiponectin gene SNP rs1501299 and SNP rs224176 may be the predisposing factors in some cancers but our results differ from what has been reported in other populations suggesting a complex relationship between genetic variations and phenotypic adiponectin levels.     

Psychological insulin resistance in geriatric patients with diabetes mellitus

Objective

To determine the extent to which geriatric patients with diabetes mellitus experience psychological insulin resistance (PIR).

Methods

A total of 67 unselected geriatric patients with diabetes (mean age 82.8 ± 6.7 years, diabetes duration 12.2 [0.04–47.2] years, 70.1% female) were recruited in a geriatric care center of a university hospital.A comprehensive geriatric assessment (CGA) was performed including WHO-5, Hospital Anxiety and Depression Scale (HADS), Mini Mental State Examination (MMSE) and Barthel-Index. We assessed PIR using the Barriers of Insulin Treatment Questionnaire (BIT) and the Insulin Treatment Appraisal Scale in a face-to-face interview.

Results

Insulin-naïve patients (INP) showed higher PIR scores than patients already on insulin therapy (BIT-sum score: 4.3 ± 1.4 vs. 3.2 ± 1.0; p < 0.001). INP reported in the BIT increased fear of injection and self-testing (2.4 ± 2.4 vs. 1.3 ± 0.8; p = 0.016), expect disadvantages from insulin treatment (2.7 ± 1.6 vs. 1.9 ± 1.4; p = 0.04), and fear of stigmatization by insulin injection (5.2 ± 2.3 vs. 3.6 ± 2.6; p = 0.008). Fear of hypoglycemia, however, did not differ significantly (6.3 ± 2.8 vs. 5.1 ± 3.1; p = 0.11). Depression was not shown to be a barrier to insulin therapy.

Conclusion

INP with diabetes have a significantly more negative attitude toward insulin therapy in comparison to patients already on insulin.

Practice implications

Systematic assessment of barriers of insulin therapy, individualized diabetes treatment plans and information of patients may help to overcome such negative attitudes, leading to quicker initiation of therapy, improved adherence to treatment and a better quality of life.     

The relationship between anti-Mullerian hormone, androgen and insulin resistance on the number of antral follicles in women with polycystic ovary syndrome

BACKGROUND: Anti-Müllerian hormone (AMH) is a biomarker that predicts the number of antral follicles and is involved in follicle arrest for women with polycystic ovary syndrome (PCOS). We investigated the association between the characteristic hyperandrogenemia, insulin resistance (IR), AMH, and the morphology and size of ovaries for women with PCOS. METHODS: A total of 99 Taiwanese women with PCOS who were willing to undergo vaginal ultrasonography were enrolled in this cross-sectional study. RESULTS: The number of antral follicles and the ovarian volume showed a significant correlation with AMH, total testosterone and the free androgen index, but not with age, body mass index (BMI) or the homeostasis model assessment of insulin resistance (HOMA-IR). AMH had a significant negative association with both BMI and HOMA-IR. Multiple stepwise regression analysis demonstrated that AMH, BMI and total testosterone were independently related to the number of antral follicles. AMH and total testosterone were the main determinants for ovarian volume in a stepwise regression model. CONCLUSIONS: Our results suggest that not only the AMH level, but also obesity, IR and elevated androgen levels may relate to the development of the large size of antral follicle pool and ovarian volume in women with PCOS. Obesity and IR may enhance the follicular excess through the dysregulation of AMH or through the pathway of hyperandrogenemia. These findings might partly explain why adequate body weight management and improvement in IR can improve the ovulatory function for women with PCOS.     

子痫前期患者血清及胎盘中IGF-I、瘦素水平变化及相关性研究

目的:探讨子痫前期患者血清及胎盘中胰岛素样生长因子-I(IGF-I)、瘦素(leptin)水平变化及其相互关系。方法:采用酶联免疫吸附法及免疫组织化学法分别检测80例重度子痫前期患者和50例正常妊娠妇女血清及胎盘组织中IGF-1、leptin的水平。结果:轻度和重度子痫前期组孕妇分娩前和脐静脉血IGF-I水平均明显低于对照组孕妇,leptin水平均明显高于对照组孕妇,且随子痫前期的病情加重,分娩前和脐静脉血IGF-I水平亦随之降低,leptin水平亦随之增加,各组两两比较有显著性差异(P<0.05)。在对照组、轻度子痫前期组、重度子痫前期组胎盘组织中IGF-I和leptin的表达比较有显著性差异(P<0.05)。结论:IGF-I和leptin可能参与了子痫前期的发生发展过程,且可作为监测患者病情变化的参考指标。     

Caveolae与胰岛素抵抗

Caveolae（小凹结构）是细胞质膜上一种富含胆固醇和鞘脂的特异性囊状结构脂筏。近年来研究发现其特异蛋白Caveolins（小窝蛋白）与胰岛素抵抗关系密切。Caveolins通过与胰岛素受体相互作用,参与体内葡萄糖、脂肪代谢等方面来调节胰岛素敏感性,是治疗糖尿病的新位点。     

脂肪肝与胰岛素抗性的关系

目的探讨脂肪肝与胰岛素抗性的关系。方法对30例诊断为脂肪肝患者作回顾性分析。结果多数患者合并胰岛素抗性综合征(高血压、肥胖症、糖尿病、高脂血症),18例接受口服葡萄糖耐量试验(OGTT)中,1例确诊为Ⅱ型糖尿病,17例患者中3例空腹血糖减损(IFG),1例糖耐量减退(IGT)及13例糖耐量正常(NGT)具有较正常人为高的血浆胰岛素(INS)浓度,胰岛素抗性脂数为8.91±1.52%。结论脂肪肝与胰岛素抗性所致的代谢紊乱关系紧密,呈正相关系。     

Contribution of leptin to the formation of neuroleptic obesity in patients with schizophrenia during antipsychotic therapy

We studied the dynamics of serum leptin level and some anthropometric values in patients with schizophrenia treated with risperidone, olanzapine, and clozapine showed gender-dependent specific correlations between the studied parameters. Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 9, pp. 324–326, September, 2008