【作者】 林爱清；

【导师】 李明龙；

【作者基本信息】 山东大学 ， 老年医学， 2010， 硕士

【摘要】 目的：通过观察新诊断的老年糖尿病患者胰岛素分泌的特点,测定血清中胰淀素、褪黑素含量,探讨胰淀素和褪黑素与老年糖尿病患者胰岛β细胞功能之间的关系,研究老年糖尿病发生的可能机制。方法：收集初诊2型糖尿病(T2DM)患者70例,其中老年起病糖尿病组(EOD组；年龄≥60岁)37例,成年起病糖尿病组(AOD组；25岁≤年龄<60岁)33例,均行口服葡萄糖耐量试验(OGTT),根据OGTT试验各时点血糖、胰岛素值计算血糖曲线下面积(AUCg)、胰岛素曲线下面积(AUCi)、30min胰岛素增量与葡萄糖增量比值(△I30／△G30),胰岛β细胞功能指数(HOMA-p)及胰岛素抵抗指数(HOMA-IR)。采用酶联免疫(ELISA)法检测患者空腹血清胰淀素、褪黑素水平,与老年健康对照组(EHC组；30例)相比较。同时测定所有受试者的空腹血清甘油三脂(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C),测量血压、身高、体质量、腰围及臀围,计算体质指数(BMI)及腰臀比(WHR),并对结果进行统计分析。结果：1.与AOD组相比,EOD组OGTT2 h血糖[(15.17±3.03)vs(13.59±2.76)mmol／L,P<0.05]、2 h胰岛素[(73.34±43.39)vs(64.22±29.75)uIU／ml,P<0.05]及HOMA-IR[(4.20±1.67)vs(3.49±1.83),P<0.05]明显升高,而HOMA-β[(58.20±24.89)vs(81.20±40.80),P<0.01]、△I30／／△G30(2.62±0.43)vs(3.37±0.58),P<0.01]明显降低。EOD组AUCg、AUCi均较AOD组略高,但差异无统计学意义(P>0.05)。2.EOD组血清胰淀素水平显著高于AOD组[(21.57±15.88)Vs(19.8±13.18)ng/L,P<0.05]和EHC组[(21.57±15.88)vs(17.82±12.15)ng/L,P<0.01],AOD组与EHC组比较,血清胰淀素水平偏高,但无统计学意义(P>0.05)。EOD组血清褪黑素水平显著低于AOD组[(6.56±1.32)vs(8.17±1.23)pg/ml,P<0.05]和EHC组[(6.56±1.32)vs(7.65±1.39)pg／ml,P<0.01],EHC组与AOD组比较,血清褪黑素水平稍低,但无统计学意义(P>0.05)。3.血清胰淀素与HOMA-IR(r=0.498,P=0.016)、空腹血清胰岛素(Fins)(r=0.517,P=0.031)、AUCi(r=0.516,P=0.021)呈正相关(P<0.05),与HOMA-β(r=-0.461,P=0.003)呈负相关,与空腹血糖(FBG)、血脂及AUCg、△I30／△G30、WHR、BMI均未见明显相关性。4.血清褪黑素与与HOMA-p(r=0.403,P=0.016)、HDL-C(r=0.416,P=0.018)呈正相关；与HOMA-IR(r=0.549,P=0.019)、AUCi(r=-0.521,P=0.014)、WHR(r=-0.514,P=0.023)、FBG(r=-0.345,P=0.032)、LDL-C(r=0.479,P=0.012)呈负相关,与AUCg、BMI、△I30／／△G30均未见明显相关性。结论：1、老年T2DM患者存在明显的胰岛β细胞功能下降及胰岛素早相分泌受损,同时存在一定程度的胰岛素抵抗及胰岛素释放高峰延迟,提示胰岛β细胞功能异常是老年糖尿病患者糖代谢紊乱的主要原因。2、与健康老年人相比,老年起病糖尿病患者血清胰淀素水平明显增高,褪黑素水平明显降低,提示高胰淀素血症及低褪黑素血症可能与老年糖尿病的发病机制有关。3、血清胰淀素水平与胰岛β细胞功能呈负相关关系,与肥胖、胰岛素抵抗呈正相关关系,提示血清胰淀素水平可作为评价胰岛β细胞功能的指标之一。4、血清褪黑素水平与胰岛β细胞功能呈正相关关系,同时与血脂、胰岛素抵抗指数等存在负相关关系,推测其有可能成为评价胰岛β细胞功能的新指标之一。更多还原

【Abstract】 Objective The present study was to explore the relationship between isletβ-cell function and the serum levels of amylin and melatonin by observing the feature of isletβ-cell function and measuring the serum levels of amylin and melatonin in newly diagnosed elderly diabetic patients, furtherly to explore the possible mechanism of senile diabetes.Methods 70 newly diagnosed subjects with type 2 diabetes were divided into elderly-onset diabetes group (EOD, aged 60 to 94) and adult-onset diabetes group (AOD, aged 25 to 59 years), oral glucose tolerance test (OGTT) was detected and the area under the curve of glucose (AUCg)、the area under the curve of insulin (AUCi)、the function of pancreatic beta-cell(HOMA-β)、the ratio of the increment of insulin to that of serum glucose of the initial 30 minutes(△I30/△G30) and the homeostasis model assessment of insulin resistance (HOMA-IR) after OGTT was calculated. The levels of serum amylin and melatonin of all patients were determined with ELISA, compared with that of 30 healthy aged subjects(elderly healthy control group, EHC). For all of the subjects, fasting serum triglycerid (TG)、total cholesterol(TC)、high density lipoprotein cholesterol (HDL-C)、low density lipoprotein cholesterol (LDL-C) and blood pressure were measured and body mass index (BMI), waist/hip ratio(WHR) were calculated.Results 1. Compared with AOD group, EOD group had lower value of HOMA-β[(58.20±24.89) vs (81.20±40.80), P＜0.01] and△I30/△G30[(2.62±0.43) vs (3.37±0.58), P＜0.01], but had higher values of OGTT 2 h serum glucose[(15.17±3.03) vs (13.59±2.76) mmol/L, P＜0.05], serum insulin[(73.34±43.39) vs (64.22±29.75) uIU/ml, P＜0.05] and HOMA-IR[(4.20±1.67) vs (3.49±1.83), P＜0.05], though the values of AUCg and AUCi were higher in EOD group than that in AOD group, no significant difference was found.2. The serum amylin level in EOD group was obviously higher than that in AOD group[(21.57±15.88) vs (19.8±13.18) ng/L, P＜0.05] and EHC group[(21.57±15.88) vs (17.82±12.15) ng/L, P＜0.01].There wasn’t obvious difference between AOD group and EHC group on serum amylin level(P＞0.05).The serum melatonin level in EOD group was obviously lower than that in AOD group[(6.56±1.32) vs (8.17±1.23) pg/ml, P＜0.05] and EHC group[(6.56±1.32) vs (7.65±1.39) pg/ml, P＜0.01]; There wasn’t obvious difference between AOD group and EHC group on serum melatonin level(P＞0.05).3. The correlation analysis results showed that:serum amylin level had positive correlation with HOMA-IR(r= 0.498, P= 0.016), fasting serum insulin(r= 0.517, P= 0.031), AUCi(r= 0.516, P= 0.021) and had negative correlation with HAMA-β(r=-0.461, P= 0.003). The serum amylin had no significant correlation with AUCg, FBG, blood lipids,△I30/△G30, WHR and BMI(P＞0.05).4. The level of serum melatonin had positive correlation with HAMA-β(r= 0.403, P= 0.016) and HDL-C(r= 0.416, P= 0.018) and had negative correlation with HOMA-IR(r=-0.549, P= 0.019), AUCi(r=-0.521, P= 0.014), WHR(r=-0.514, P = 0.023), fasting blood glucose(r=-0.345, P= 0.032) and LDL-C(r=-0.479, P= 0.012), the serum melatonin had no significant correlation with AUCg,△I30/△G30 and BMI(P＞0.05).Conclusion 1. Newly diagnosed elderly diabetic patients have obviousβ-cell deterioration and impaired early-phase insulin secretion, at the same time have a certain degree of insulin resistance and delayed peak of insulin release, suggesting that isletβ-cell dysfunction is the main reason of glucose metabolism disorder in elderly diabetic patients.2. Compared with the healthy elderly, the elderly-onset diabetic patients had significantly higher level of amylin and lower level of melatonin, suggesting that the increased serum amylin and decreased serum melatonin may be related to the pathogenesis of senile diabetes.3. The serum amylin level had significant negative correlation relationship with islets beta-cell function and had positive correlation relationship with obesity and insulin resistance, it is one of useful markers which estimate the function of pancreaticβ-cells.4. The serum melatonin level had positive correlation with pancreatic beta-cell function and had negative correlation relationship with blood lipids and insulin resistance index, speculating that it may become a new index of evaluation of isletβ-cell function.更多还原