中药黄芩甙与黄连素对糖尿病鼠醛糖还原酶活性作用的观察

利用糖尿病ＳＤ大鼠动物模型，观察了中药黄芩甙、黄连素及的醛糖还原酶抑制剂Ｓｏｒｂｉｎｉｌ对大鼠组织醛糖还原酶活性和肾脏病变的影响。     

糖尿病患者红细胞醛糖还原酶活性的初步观察

利用ＤＥＡＥ－纤维素柱层析法对２３例糖尿病患者红细胞醛糖还原酶活性进行了测定，并对其性质做了时一步分析。结果发现，糖尿病红细胞醛糖还原活性明显升高，酶活性升主七血糖值呈正相关，高血压糖时醛糖还原酶不仅对多种底物的Ｋｍ值（包括葡萄糖）显著下降，而且对醛糖还原酶抑制剂Ｓｏｒｂｉｎｉｌ的抑制不敏感。因此，红细胞ＡＲ活性测定可以作为判断糖尿病慢性并发症病情及评估醛糖还原抑制剂疗效的一项重要指标。     

黄芩苷对糖尿病大鼠组织醛糖还原酶活性及肾脏细胞凋亡的影响

目的研究醛糖还原酶(AR)、凋亡相关蛋白Bcl-2和Bax与糖尿病肾病(DN)的关系,探讨醛糖还原酶抑制剂(ARIs)对DN的治疗作用。方法雄性Wistar大鼠40只,随机分为正常对照组、糖尿病组、依帕司他组、黄芩苷组,每组10只。除正常对照组外,其余各组大鼠腹腔注射STZ(60mg/kg),72h后建立糖尿病大鼠模型。依帕司他组灌胃依帕司他10mg.kg-1.d-1,黄芩苷组灌胃黄芩苷150mg.kg-1.d-1。16w后处死大鼠,测定晶体、肾脏组织AR活性,观察Bcl-2、Bax的表达,取部分肾皮质病理观察、电镜观察细胞凋亡的形态学变化。结果与正常对照组相比,糖尿病组晶体、肾脏皮质AR活性明显升高(P<0.001),两治疗组AR活性明显较糖尿病组降低(P<0.01),而血糖无明显变化。糖尿病组肾脏Bcl-2、Bax蛋白表达增加,治疗组的Bcl-2蛋白表达较糖尿病组增多,而Bax蛋白表达较糖尿病组减少。透射电镜下见糖尿病组肾脏肾小管上皮细胞呈典型的凋亡形态学改变,治疗组大鼠肾组织细胞凋亡改变明显减轻。糖尿病组肾小球基底膜增厚,系膜区域扩大,治疗组病变减轻。结论ARIs通过抑制AR活性,调节Bax、Bcl-2的表达抑制细胞凋亡,延缓DN的发展。黄芩苷对AR抑制作用与依帕司他相似。     

荧光法动态观察糖尿病大鼠红细胞醛糖还原酶活性

目的比较测定醛糖还原酶(AR)活性的两种荧光法(碱终止法和酸终止法)的差异,应用其中较好的一种动态观察糖尿病(DM)大鼠红细胞AR活性。方法SD大鼠随机等分为四组正常对照组和DM20、40、60d组,用辅酶(NADPH或NADP)、DL甘油醛、磷酸缓冲液等组成各自的反应体系,比较碱终止法和酸终止法测定AR活性的灵敏度和重复性,择其优者测定各组大鼠红细胞AR活性。结果NADP和NADPH浓度相同时酸终止法所测荧光值较高;辅酶浓度在0～400μmol/L时标准曲线呈线性;酸终止法标准曲线的批内和批间变异系数分别为0.83%和2.28%,碱终止法为17.88%和16.69%,两法所测标本的批内和批间变异系数分别为4.25%、7.12%和1.13%、13.07%;高氯酸可消除血红蛋白对荧光的影响;DM组AR活性较正常对照增高(P<0.05),且随病程延长活性增加,但DM组间AR活性无统计学差异;血糖与AR活性正相关(r=0.873)。结论酸终止法较碱终止法简便、灵敏、准确、稳定。DM大鼠红细胞AR活性增高,并随病程延长有增加的趋势;提示AR活性的动态观察有可能作为糖尿病并发症发展进程的监测指标。     

黄芩苷对糖尿病大鼠组织醛糖还原酶活性及视网膜细胞凋亡的影响

取大鼠40只,随机分为NC组、DM组、依帕司他治疗组、黄芩苷治疗组。治疗16周后,测定视网膜组织醛糖还原酶（AR）活性及Bcl-2和Bax蛋白表达水平,发现AR活性在DM组明显升高,治疗组明显降低（P均〈0.01）。视网膜Bcl-2、Bax蛋白表达在DM组明显增加,治疗组明显减少。结果表明AR激活促进Bcl-2、Bax蛋白的表达,诱导细胞凋亡,参与DR的发生发展。醛糖还原酶抑制剂抑制AR活性,降低Bax、Bcl-2的表达,从而抑制细胞凋亡,延缓DR的发展。     

糖尿病患者红细胞醛糖还原酶测定的方法学探讨

糖尿病患20人、健康对照15人,分别应用三种方法测定其红细胞AR,同时测定血糖。结果：三种方法测定的AR值糖尿病组均显高于正常对照,AR值与血糖均相关,柱层析法、荧光法,与ELISA测定的AR水平均有良好的相关性（γ值分别为0．91,0．82,P值均＜0．01）。结论：糖尿病患红细胞AR不仅活性增加,而且水平也升高。     

川芎嗪对糖尿病鼠醛糖还原酶活性及视网膜细胞凋亡影响

雄性Wistar大鼠40只，随机平均分为4组，正常对照组、糖尿病组、糖尿病依帕司他（10mg／kg／d）治疗组、糖尿病川芎嗪（100mg／kg／d）治疗组，蝮腔注射链脲佐菌素（65mg／kg）诱发糖尿病。16周后，处死大鼠，分离晶体，测定组织AR活性，观察视网膜Bcl-2、Bax的表达。结果：1．与正常对照组相比，糖尿病组AR活性明显升高（P〈0．001），依帕司他治疗组、川芎嗪治疗组AR活性较糖尿病组明显降低（P〈0．01），而血糖无明显变化。2．糖尿病组视网膜Bcl-2、Bax蛋白表达明显增加，依帕司他治疗组、川芎嗪治疗组的Bcl-2、Bax蛋白表达较糖尿病组明显减少。结沦：1．AR过度激活通过促进Bcl～2、Bax蛋白的表达诱导细胞凋亡，而参与DR的发生与发展。2．ARts通过抑制醛糖还原酶活性，调节Bax、Bcl-2的表达抑制细胞凋亡，延缓DR的发展。3．川芎嗪对AR抑制作用与典型ARIs依帕司他相似，且价格低、副作用少，值得临床推荐应用。     

川芎嗪对糖尿病鼠醛糖还原酶活性及视网膜细胞凋亡影响

雄性Wistar大鼠40只,随机平均分为4组,正常对照组、糖尿病组、糖尿病依帕司他(10mg/kg/d)治疗组、糖尿病川芎嗪(100mg/kg/d)治疗组,腹腔注射链脲佐菌素(65mg/kg)诱发糖尿病.16周后,处死大鼠,分离晶体,测定组织AR活性,观察视网膜Bcl-2、Bax的表达.结果1.与正常对照组相比,糖尿病组AR活性明显升高(P＜0.001),依帕司他治疗组、川芎嗪治疗组AR活性较糖尿病组明显降低(P＜0.01),而血糖无明显变化.2.糖尿病组视网膜Bcl-2、Bax蛋白表达明显增加,依帕司他治疗组、川芎嗪治疗组的Bcl-2、Bax蛋白表达较糖尿病组明显减少.结论1.AR过度激活通过促进Bcl-2、Bax蛋白的表达诱导细胞凋亡,而参与DR的发生与发展.2.ARts通过抑制醛糖还原酶活性,调节Bax、Bcl-2的表达抑制细胞凋亡,延缓DR的发展.3.川芎嗪对AR抑制作用与典型ARIs依帕司他相似,且价格低、副作用少,值得临床推荐应用.     

糖尿病患者红细胞醛糖还原酶测定的方法学探讨

糖尿病患者20人、健康对照15人,分别应用三种方法测定其红细胞AR,同时测定血糖.结果三种方法测定的AR值糖尿病组均显著高于正常对照,AR值与血糖均相关,柱层析法、荧光法,与ELISA测定的AR水平均有良好的相关性(γ值分别为0.91,0.82,P值均＜0.01).结论糖尿病患者红细胞AR不仅活性增加,而且水平也升高.     

Ⅱ型糖尿病患者红细胞的醛糖还原酶活性与细胞损伤

应用荧光法测定了15例无并发症的Ⅱ型糖尿病患者红细胞内醛糖还原酶的活性,患者的酶活性明显高于正常对照。同时用气相色谱法测量了红细胞内糖醇的浓度,患者的山梨醇和果糖的浓度明显高于对照,而两者的肌醇浓度差异无显著性。患者全血还原型谷胱甘肽和氧化型谷胱甘肽的浓度明显低于正常对照。实验结果提示:醛糖还原酶的激活加速了多元醇代谢途径,但山梨醇在细胞内的蓄积加速它向果糖转化,从而缓解山梨醇的堆积和细胞损伤。     

醛糖还原酶基因内含子多态性与2型糖尿病肾病的相关性研究

209例2型糖尿病人和84名健康对照者的醛糖还原酶基因第8内含子第95位点AC多态性研究发现基因型AA的频度,糖尿病肾病患者是7%,明显高于非肾病组(1%)和健康对照组(1%)。这提示,该酶第8内含子基因型AA可能是糖尿病肾病的危险因子。     

Polyol pathway and diabetic nephropathy revisited: Early tubular cell changes and glomerulopathy in diabetic mice overexpressing human aldose reductase

Aims/Introduction: The polyol pathway has long been involved in the pathogenesis of diabetic nephropathy. It remains still unclear, however, how the polyol pathway is implicated in this process. We explored the effects of the enhanced polyol pathway on renocortical tubular cells and glomeruli in experimentally‐induced diabetes. Materials and Methods: Transgenic mice (Tg) overexpressing human aldose reductase were made diabetic by streptozotocin and followed for 8 weeks. Renocortical pathology, expressions of tonicity‐responsive enhancer binding protein (TonEBP) and carboxymethyllysine of advanced glycation end‐products, were examined. Wild‐type non‐transgenic mice (Wt) were also made diabetic and served as controls. Results: Diabetic Tg showed augmented expression of TonEBP in renocortical tubular cells with vacuolated degenerative changes. These structural changes were associated with pronounced deposition of carboxymethyllysine. There was a significant increase in kidney weight, glomerular size, and mesangial area in diabetic animals and there was a trend for more severe changes in these measures in diabetic transgenic mice compared with those in control diabetic mice. Treatment with aldose reductase inhibitor significantly prevented polyol accumulation, mesangial expansion and expressions of TonEBP and carboxymethyllysine in diabetic Tg, but its effects on the renal structure were equivocal in control diabetic Wt. Conclusions: Our findings suggest that tubuloglomerular change might contribute to early diabetic nephropathy under the influence of the enhanced polyol pathway. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00071.x , 2010)     

红细胞醛糖还原酶测定荧光法的建立及临床应用

红细胞醛糖还原酶测定荧光法的实验探讨。方法利用ＮＡＤＰＨ、ＤＬ－甘油醛 ,磷酸缓冲液和适量红细胞溶血液组成的反应体系,建立了一种红细胞醛糖还原酶的荧光测定法,并对酶反应最适条件进行了实验探讨。     

醛糖还原酶基因5’端(AC)n多态性对2型糖尿病患者红细胞醛糖还原酶活性的影响

目的　探讨醛糖还原酶 (AR)基因 5’端 (AC) n 的多态性对 2型糖尿病 (DM )红细胞AR活性的影响。方法　 16 3例 2型DM分为无微血管病变 (NDC)组 (6 6例 )和微血管病变 (DMAP)组(97例 ) ,正常对照 (CON)组 42例 ;另按AR基因 5’端 (AC) n 的等位基因类型分为DM携带Z 2等位基因 (DZ 2 )组 (5 4例 )、DM携带Z - 2等位基因 (DZ - 2 )组 (35例 )、DM同时携带Z 2和Z - 2等位基因 (Z 2 /Z - 2 )组 (18例 )、DM不携带Z 2和Z - 2等位基因 (X/X)组 (5 6例 )、对照者携带Z 2等位基因 (NZ 2 )组 (2 1例 )和对照者携带Z - 2等位基因 (NZ - 2 )组 (7例 )。用改良Sriratava法测定AR活性并比较其在各组间的差异。结果　DMAP组、NDC组和CON组间的AR活性 (ARA)差异有显著性 ,DMAP组最高 ,NDC组次之 ,CON组最低 (P <0 .0 0 1)。DM组携带Z - 2和Z 2等位基因各亚组中 ,DZ - 2组ARA最高 ,Z - 2 /Z 2和X/X组居中 ,DZ 2组最低 ,差异有显著性统计学意义(P <0 .0 0 1)。DZ - 2和NZ - 2组的ARA分别高于DZ 2和NZ 2组 ,DZ - 2和DZ 2组的ARA分别高于NZ - 2和NZ 2组 (P均 <0 .0 0 1)。结论　AR的激活对DMAP的发生和发展起重要作用。Z - 2等位基因可能是AR的激活因子 ,Z 2等位基因则为其抑制因子。     

筋脉通对糖尿病大鼠坐骨神经传导速度、醛糖还原酶及山梨醇浓度的影响

目的观察中药复方筋脉通对糖尿病大鼠坐骨神经传导速度、坐骨神经组织和红细胞内醛糖还原酶活性(AR)及山梨醇(SNS)浓度的影响,并探讨其作用机理。方法采用链脲佐菌素(STZ)糖尿病(DM)大鼠模型,给予中药复方筋脉通灌胃,并以氨基胍为对照,疗程8周。观察该制剂对糖尿病大鼠坐骨神经传导速度、坐骨神经组织和红细胞醛糖还原酶活性(AR)及对山梨醇(SNS)浓度的影响。结果经筋脉通治疗后,糖尿病大鼠坐骨神经传导速度增快,坐骨神经和红细胞SNS浓度、坐骨神经AR明显降低,和对照组比较有显著性差异(P<0.05～0.01)。红细胞内AR有降低的趋势,但无统计学意义。对血糖有下降作用。结论提示筋脉通对改善糖尿病神经病变有一定的疗效。     

Increased erythrocyte aldose reductase activity in type 1 diabetic patients.

Elevated erythrocyte sorbitol levels have been demonstrated in diabetic patients. In order to explain the enhanced sorbitol formation, it has been suggested that aldose reductase might be activated by hyperglycaemia. Although aldose reductase activity has been reported to be increased in some tissues of diabetic patients, the effects of varying concentrations of glucose on the enzyme activity in vivo are unknown. To determine whether or not erythrocyte aldose reductase activity is increased in diabetic patients and is affected by glucose levels, we collected blood samples from 10 Type 1 diabetic patients while fasting and 2 h after a standard meal. We measured the activity of erythrocyte aldose reductase after partial purification by column chromatography. The results showed that erythrocyte aldose reductase activity was significantly increased in diabetic patients as compared with non-diabetic subjects (7.3 +/- 0.7 (+/- SE) vs 5.2 +/- 0.3 u l-erythrocytes-1, p less than 0.05). No correlation, however, was observed between fasting plasma glucose levels and the enzyme activity, and acute elevation of the blood glucose level did not affect the enzyme activity.     

Neutrophil aldose reductase activity as a potential marker for neuropathy and cataract in diabetes.

Aldose reductase activity can be measured in the neutrophil and it has been proposed that this may be a marker for risk of complications in diabetes. We have studied aldose reductase activity in neutrophil, nerve, and lens in diabetic patients undergoing sural nerve biopsy or cataract extraction. A correlation was demonstrated between lens and neutrophil aldose reductase activity (r = 0.53, p = 0.01) but no correlations were demonstrated between nerve aldose reductase activities and nerve morphometry, nerve function or neutrophil aldose reductase activity. No significant difference was found between neutrophil aldose reductase activities in groups of patients with severe neuropathy, or cataract, or no complications (24 (interquartile range 16-32) vs 24 (16-40) vs 24 (16-40) nmol NADPH min-1 10(8)-cells-1). In a group of 56 Type 1 diabetic patients screened within 6 years of diagnosis, multiple regression analysis failed to show any relationship between neutrophil aldose reductase activity and abnormalities of neurophysiological function. These results suggest that neutrophil aldose reductase activity cannot be used as a marker for the development of cataract or neuropathy in diabetes.     

醛糖还原酶基因启动子区C(-106)T多态与糖尿病肾病的相关性

对2型糖尿病伴有糖尿病肾病患者（DN）70例、不伴DN患者64例和85例正常对照研究显示，醛糖还原酶启动子区C（-106）T的CC基因型是中国北方汉人发生DN的危险因子。