锰超氧化物歧化酶基因Ala(-9)Val多态性与2型糖尿病视网膜病变的相关性

目的 探讨锰超氧化物歧化酶(manganese superoxide dismutase,Mn-SOD)基因Ala(-9)Val多态性与2型糖尿病视网膜病变发生的关联性.方法 应用PCR-直接测序方法检测了中国湖北地区汉族264例2型糖尿病患者和198名正常对照者的Mn-SOD基因Ala(-9)Val多态性(GCT→GTT).结果 (1)2型糖尿病组与正常对照组比较,VV基因型频率(72.7%vs 67.2%,P>0.05)与V等位基因频率(76.1%vs71.0%,P>0.05)差异无统计学意义.(2)在2型糖尿病者中,有糖尿病视网膜病变(diabetic retinopathy,DR)组 VV基因型频率为79.2%,与无糖尿病视网膜病变(non-diabetic retinopathy,NDR)组(66.9%)比较,差异有统计学意义(x2=5.015,P=0.025);V等位基因频率在DR组为82.4%,NDR组为70.5%,差异亦有统计学意义(x2=10.253,P=0.001);NDR组与正常对照组比较,VV基因型频率(66.9%vs67.2%,P>0.05)及V等位基因频率(70.5%vs 71.0%,P>0.05)差异无统计学意义,V等位基因与2型糖尿病视网膜病发生相关(OR=1.96,95%CI:1.29-2.97).(3)基因型为VV型的2型糖尿病患者其Nn-SOD水平较AA型、AV型患者低,差异有统计学意义(P=0.025),其总超氧化物歧化酶有增加趋势,但差异无统计学意义(P>0.05).结论 Mn-SOD基因Ala(-9)Val多态性与2型糖尿病发病无关,但可能参与了2型糖尿病视网膜病变的发生、发展过程.     

The polymorphism of manganese superoxide dismutase is associated with diabetic nephropathy in Japanese type 2 diabetic patients

 We evaluated the relationship of an alanine or valine polymorphism at amino acid sequence 16 [Val(16)Ala] of manganese superoxide dismutase (Mn-SOD) with diabetes and diabetic nephropathy in Japanese type 2 diabetic patients. Val(16)Ala genotyping of Mn-SOD was done by polymerase chain reaction-restriction fragment length polymorphism with a restriction enzyme (Bsaw I) in 478 Japanese type 2 diabetic patients and 261 nondiabetic Japanese healthy subjects. The genotype distribution of diabetic and nondiabetic subjects was then compared, and the association of genotype with diabetic nephropathy was evaluated in the diabetic patients. The allele frequency and genotype of the diabetic patients were not different from those of the healthy nondiabetic subjects. The VV type showed a significantly higher frequency in the diabetic patients with nephropathy than did the AA or VA type [VV type: normoalbuminuria 70.8%, microalbuminuria 84.8% (P = 0.0057), macroalbuminuria 84.1% (P = 0.0128)]. Furthermore, logistic regression analysis showed that this polymorphism is associated with diabetic nephropathy independently (odds ratio = 0.461925, P = 0.03). Accordingly, the Val(16)Ala polymorphism of Mn-SOD may be unrelated to the etiology of type 2 diabetes, but it seems to be associated with diabetic nephropathy in Japanese type 2 diabetic patients. Received: August 5, 2002 / Accepted: December 3, 2002 Correspondence to:Y. Tanaka     

Manganese superoxide dismutase gene polymorphism (V16A) is associated with diabetic retinopathy in Slovene (Caucasians) type 2 diabetes patients

Substantial data indicate that oxidative stress is involved in the development of diabetic retinopathy. Two candidate genes that affect the oxidative stress are manganese mitochondrial superoxide dismutase (Mn-SOD) and endothelial nitric oxide synthase (eNOS). The aim of the present study was to examine the role of the V16A polymorphism of the Mn-SOD gene and the 4a/b polymorphism of the eNOS gene in the development of diabetic retinopathy in Caucasians with type 2 diabetes. In this cross sectional case-control study 426 unrelated Slovene subjects (Caucasians) with type 2 diabetes mellitus were enrolled: 283 patients with diabetic retinopathy and the control group of 143 subjects with type 2 diabetes of duration of more than 10 years who had no clinical signs of diabetic retinopathy. A significantly higher frequency of the VV genotype of the V16A polymorphism of the Mn-SOD was found in patients with diabetic retinopathy compared to those without diabetic retinopathy (OR=2.1, 95% whereas the 4a/b polymorphism of the eNOS gene failed to yield an association with diabetic retinopathy. We may conclude that the VV genotype of the V16A polymorphism of the Mn-SOD gene was associated with diabetic retinopathy in Caucasians with type 2 diabetes, therefore it might be used as a genetic marker of diabetic retinopathy in Caucasians.     

Leukocyte lipid peroxidation, superoxide dismutase and catalase activities of type 2 diabetic patients with retinopathy

Increased oxidative stress might play an important role in the initiation and progression of diabetic complications. The present study has been undertaken to investigate whether there is any relationship between retinopathy degree and leukocyte superoxide dismutase (SOD) and catalase (CAT) activities and lipid peroxidation (LPO) in diabetic individuals with type 2 diabetic retinopathy. Patients were groupped with respect to the degree of retinopathy. Leukocyte malondialdehyde (MDA) levels, and SOD and CAT activities were measured in patients with type 2 diabetes mellitus (n=41) and nondiabetic healthy controls (n=23). Leukocyte LPO of the type 2 diabetic patients with retinopathy was significantly increased (p < 0.001), whereas SOD and CAT activities were decreased (p<0.001 and p<0.001, respectively) compared to those of controls. MDA concentrations rose while SOD and CAT activities fell with increasing severity of diabetic retinopathy, altough there was no significant difference in comprasion of the parameters mentioned above between the diabetic patients with and without retinopathy. Our results show that leukocytes in patients with type 2 diabetic retinopathy are affected by oxidative stress which might be contribute to pathogenesis of diabetic retinopathy. Prospective studies are needed to evaulate the relationship between the leukocyte antioxidants status and DR.     

Association analysis of nine candidate gene polymorphisms in Indian patients with type 2 diabetic retinopathy

Background  

Diabetic retinopathy (DR) is classically defined as a microvasculopathy that primarily affects the small blood vessels of the inner retina as a complication of diabetes mellitus (DM).It is a multifactorial disease with a strong genetic component. The aim of this study is to investigate the association of a set of nine candidate genes with the development of diabetic retinopathy in a South Indian cohort who have type 2 diabetes mellitus (T2DM).     

糖尿病视网膜病MTHFR基因多态性及其与血浆同型半胱氨酸水平的关系

目的：研究亚甲基四氢叶酸还原酶（methylenetetrahydrofolate reductase,MTHFR）基因多态性及血浆同型半胱氨酸水平与2型糖尿病视网膜病的关系。方法：应用聚合酶链反应－限制性内切酶片段长度多态性技术检测208例2型糖尿病患者（其中110例伴视网膜病）及57名正常对照的MTHFR C677T基因型，采用高效液相色谱法测定血浆同型半胱氨酸水平。结果：糖尿病视网膜病组MTHFR基因TT纯合基因型、CT杂合基因型及T等位基因频率（分别为28．18％、41．82％、49．09％）均明显高于糖尿病不伴视网膜病组（分别为18．37％、29．59％、33．16％）及正常对照组（分别为17．54％、28．07％、31．58％），基因型和等位基因频率分布差异均有显著性（P＜0．01），而MTHFR基因多态性在糖尿病不伴视网膜病组与正常对照组之间差异无显著性（P＞0．05），T等位基因与糖尿病视网膜病的发生密切相关（OR＝1．94，95％CI；1．31－2．88）。糖尿病视网膜病组、糖尿病不伴视网膜病组及正常对照组中，MTHFR基因有C677T突变者血浆同型半胱氨酸水平均显著高于无基因突变者。结论：MTHFR基因C677T位碱基突变致血浆同型半胱氨酸水平升高可能是糖尿病视网膜病发病的重要遗传因素。     

Oxidative stress and overexpression of manganese superoxide dismutase in patients with Alzheimer''s disease

Substantial evidence supports the hypothesis that oxygen free radicals are involved in various neurodegenerative disorders. To assess the presence of oxidative stress in Alzheimer's disease (AD) we examined the activity of the enzyme copper-zinc superoxide dismutase (CuZnSOD) in red blood cells, the levels of the mitochondrial inducible enzyme manganese superoxide dismutase (MnSOD) mRNA in lymphocytes, and the total radical-trapping antioxidant capacity (TRAP) in plasma of AD patients and in a group of age-matched non-demented controls. We found that CuZnSOD activity (P<0.01 vs. controls) was significantly increased as well as the MnSOD mRNA levels while the total antioxidant status (P<0.001 vs. controls) was decreased in AD patients. These findings support the role of oxidative alterations in the pathogenetic mechanism underlying AD neurodegeneration.     

Differential expression of manganese containing superoxide dismutase in patients with breast cancer in Taiwan

This study used Western blot analysis to measure the expression of superoxide dismutases (Mn-SOD and Cu/Zn-SOD) in breast cancer tissues from 57 patients. Mn-SOD expression in the breast cancer tissues averaged 1.5-fold higher than in the adjacent tumor-free tissues (p <0.05). There was no significant difference in Cu/Zn-SOD expression between neoplastic and tumor-free breast tissues. This study shows a significant increase of Mn-SOD expression in breast cancer tissues. The authors speculate that up-regulation of Mn-SOD expression induced by oxidative stress or local inflammation may contribute a selective growth advantage to tumor cells compared to their normal counterparts.     

Urinary 6-sulfatoxymelatonin level in diabetic retinopathy patients with type 2 diabetes

Melatonin is a powerful antioxidant. Decreased melatonin excretion has been reported to be associated with several oxidative stress-related diseases. The urinary metabolite of melatonin, 6-sulfatoxymelatonin (aMT6s), has proved to be a very reliable index of melatonin production. The present study aims to evaluate the level of urinary aMT6s in patients with type 2 diabetes mellitus and diabetic retinopathy. Urine samples were collected from 10 patients with diabetes and no diabetic retinopathy (NDR), 19 patients with nonproliferative diabetic retinopathy (NPDR), 38 patients with proliferative diabetic retinopathy (PDR), and 16 subjects without diabetes mellitus, who served as controls. The level of aMT6s in specimens was assayed by a commercial aMT6s ELISA kit, creatinine levels were also measured for each sample to get urinary aMT6s/creatinine ratio. Creatinine-adjusted urinary aMT6s values were compared among four groups. The urinary aMT6s (mean ± SD) levels were 9.95 ± 2.42, 9.90 ± 2.28, 8.40 ± 1.84 and 5.58 ± 1.33 ng/mg creatinine in the controls and in patients with NDR, NPDR, or PDR, respectively. The urinary aMT6s level of the PDR group was significantly lower than that of the control, NDR and DR groups. No significant difference was found among the control, NDR and DR groups. After adjustment for various factors (age, smoking, cancer, and coronary heart disease) that may influence the aMT6s level, the odds-ratio of urinary aMT6s comparing PDR patients to controls was 0.246 (95% confidence interval = 0.108-0.558, P = 0.001). Therefore, the urinary aMT6s level is significantly decreased in diabetic patients with PDR but not in diabetic patients without PDR, which indicates that decreased urinary aMT6s level may be associated with the pathogenesis of PDR.     

2型糖尿病及其肾病与血管生成素2基因多态性的关联分析

目的 研究2型糖尿病(type 2 diabetes mellitus,T2DM)及其肾病(diabetic nephropathy,DN)发生、发展与血管生成素2(angiopoietin-2,Ang-2)基因多态性的关联性.方法 应用等位基因特异聚合酶链反应检验无亲缘关系汉族人群的2型糖尿病及其肾病患者221例、正常对照104名Ang-2基因单核苷酸多态性(single nucleotide polymorphism,SNP)759T/G、1078A/G、1233A/G在病例组中的频率,并用尿白蛋白排泄率、炎症标志物单核细胞趋化蛋白浓度变化探讨上述SNP与T2DM、DN发生发展的关联.结果 (1) Ang-2 759 T/G、1078 A/G基因型频率和等位基因频率在各组中的差异无统计学意义,而1233 A/G基因型频率和等位基因频率的差异有统计学意义(P＜0.05);(2)在校正年龄和性别等因素后,1233A/GSNP G等位基因患T2DM和DN的风险分别是A等位基因的2.265倍(95％ CI:1.223～1.402,P=0.031)和1.789倍(95％ CI:0.889～1.021,P=0.012);(3) Ang-2 1233A/G G等位基因与DN发生相关(r=1.321,OR=1.427,95％ CI:2.324～4.177,P=0.034).结论 Ang-2 1233A/G SNP与2型糖尿病的发生有关;AG+ GG基因型和等位基因G可能是DN发生、发展的风险因素.     

Ghrelin基因多态性与2型糖尿病的相关性

目的探讨ghrelin基因多态性与2型糖尿病之间的关系。方法进行ghrelin基因C408A和G346A的多态性分析,同时进行生化指标和临床参数的检测。结果正常对照组(NGT组)C408A基因型CC、CA、AA的基因型频率分别为75.4%、24.0%及0.6%。2型糖尿病组(DM组)中CC、CA及AA的基因型频率分别为70.8%、28.2%及1.0%。NGT组CC基因型者总胆固醇水平明显高于CA AA基因型者(P<0.05);DM组CC基因型者血尿酸水平明显高于CA AA基因型者(P<0.05)。在所有的受试者中未发现G346A多态性存在。结论Ghrelin基因C408A分布与等位基因频率没有明显的差异;本组人群中未发现ghrelinG346A多态性存在;C408A多态性与总胆固醇和尿酸水平相关。     

Association between polymorphism of the angiotensin I converting enzyme gene and hypertension in Turkish type II diabetic patients

It has been suggested that an insertion/deletion (I/D) polymorphism in intron 16 of the angiotensin converting enzyme (ACE) gene may be associated with essential hypertension. The aim of this study was to examine the association between ACE I/D polymorphism with blood pressure level and hypertension status in Turkish type 2' diabetic subjects. Hundred and seven hypertensive (78 female, 29 male) and 132 normotensive type 2 diabetic subjects (73 female, 59 male) and 138 sex and age matched control subjects (87 female, 51 male) without diabetes and hypertension were included into the study. The I/D polymorphism was determined by polymerase chain reaction (PCR). There were no statistically difference in genotypic and allelic frequencies of the ACE I/D polymorphism between the hypertensive and normotensive diabetic patients and control subjects. Also no significant differences was detected in systolic and diastolic blood pressure among three different genotypes. ACE I/D polymorphism does not seem to play an important role in the development of hypertension in Turkish type 2 diabetic subjects, but prospective studies may show an association between ACE gene polymorphism and the development of hypertension in diabetic subjects.     

非病毒载体介导Mn-SOD基因在小鼠肝脏的高表达

目的:研究非病毒载体介导Mn-SOD基因在小鼠肝脏的转染效率。方法:构建Mn-SOD真核表达质粒gWiz/Mn-SOD,通过肠系膜上静脉分支注射阳离子脂质体/质粒混合物,采用RT-PCR、Westernblot、SOD活力测定以及免疫组织化学染色等方法,观察小鼠肝脏Mn-SOD基因表达情况。结果:经肠系膜上静脉分支注射质粒/脂质体混合物几乎不对肝脏造成损伤,注射后8h即可检测到小鼠肝脏有明显的外源性Mn-SODmRNA和蛋白表达;转染前及转染后72h肝细胞线粒体SOD活性分别是(29±17)U/g和(272±56)U/g(P<0.01);免疫组化显示小鼠肝细胞转染率达70%。结论:阳离子脂质体可介导非病毒载体gWiz/Mn-SOD在小鼠肝脏高效安全表达。     

PPP1R3基因多态性与中国汉族人群2型糖尿病的相关性研究

目的　旨在研究 1型蛋白磷酸酶骨骼肌特异的糖原靶向调节亚单位基因 (PPP1R3)Asp90 5Tyr以及 3′ -UTR5bpD/I多态性与安徽省汉人群的 2型糖尿病 (T2DM )相关性。方法　运用PCR -RFLP法对安徽省合肥地区 36 6例汉族受试者 (T2DM患者 2 6 2例 ,健康成人 10 4例 )进行基因型测定。结果　 (1)PPP1R3基因Asp90 5Tyr以及 3′ -UTR 5bpD/I多态性的基因型及等位基因频率在T2DM与健康对照组间分布均没有显著性差异 (P >0 .0 5 )。 (2 )PPP1R3基因Asp90 5Tyr以及3′ -UTR 5bpD/I多态性间呈连锁不平衡 ,其分布频率在不同人群中不尽相同。结论　PPP1R3基因Asp90 5Tyr以及 3′ -UTR 5bpD/I多态性可能在安徽省合肥地区 2型糖尿病发病中不起重要作用。两种多态性的分布表现明显的种族性。     

Polymorphisms in manganese superoxide dismutase and catalase genes: functional study in Hong Kong Chinese asthma patients

BACKGROUND: Reactive oxygen species may contribute to the pathogenesis of asthma. Functional genetic polymorphisms of antioxidant enzymes, superoxide dismutase (SOD) and catalase are good candidates for asthma susceptibility. OBJECTIVE: To investigate the association of the manganese-containing form of SOD (MnSOD) gene at amino acid position 16 (Val16Ala) and catalase gene in the promoter at A-21T and C-262T polymorphisms and asthma in a Hong Kong Chinese population. METHODS: The association study was conducted in a case-control design in asthma patients (n=251) and healthy controls (n=316) by genotyping. The functional significance was assessed by determining erythrocyte SOD and catalase activity. RESULTS: The Val allele of MnSOD at Val16Ala and the A allele of catalase gene at A-21T were not different between patients and controls, while the C allele of catalase gene at C-262T was found to be significantly different between patients and controls (P=0.033). The less frequent variant of catalase gene (-262T) was found to be protective from the development of asthma in a Hong Kong Chinese non-smoking population (adjusted odds ratio=0.35, 0.15-0.85; P=0.017). Asthma patients had elevated erythrocyte SOD and catalase activities in comparison with healthy controls (P<0.01). However, their activities were not associated with different genotypes within healthy controls or asthma patients. CONCLUSION: This is the first report showing that SOD and catalase functional activities are not associated with their respective genetic polymorphisms but related to the presence of asthma in a Hong Kong Chinese population.     

糖尿病视网膜病变基因多态性荟萃分析新进展

糖尿病视网膜病变是成年人主要致盲的眼病之一.近年来,随着糖尿病患者的不断增加,糖尿病视网膜病变的患病率也逐年递增,国内外对于此疾病的研究也越来越多,在病因学研究中,基因多态性已成为研究的热点.将多个研究进行大样本荟萃分析可以获得更有意义的结论.本文对近几年来糖尿病视网膜病变患者的基因多态性经过荟萃分析得到的有效结果进行总结.