Resistin gene 3'-untranslated region +62G-->A polymorphism is associated with hypertension but not diabetes mellitus type 2 in a German population

OBJECTIVES: Resistin, a peptide hormone produced by adipocytes, has been associated with diabetes mellitus type 2 (DM-2) in some rodent models. In humans the exact function of resistin remains unknown. Some, but not all studies have found associations between polymorphisms in the resistin gene with DM-2. Recently a 3'-untranslated region +62G-->A polymorphism of the resistin gene has been associated with decreased risk for DM-2 and for hypertension in diabetics in a Chinese population. Purpose of the present study was to examine for the first time in a German Caucasian population the possible association between this polymorphism and DM-2, hypertension, lipoprotein levels, resistin levels as well as atherosclerosis. DESIGN, SETTING AND SUBJECTS: A total of 818 subjects participated in the study. The presence of the +62G-->A polymorphism of the resistin gene was investigated using polymerase chain reaction-restriction fragment length polymorphism in 384 subjects with DM-2 [224 men, 160 women, age 63.4 +/- 10.6 years, body mass index (BMI) 28.7 +/- 5.1 kg m(-2)] and in 434 nondiabetic age- and sex-matched control subjects (248 men, 186 women, age 64.4 +/- 6.5 years, BMI 26.5 +/- 3.7 kg m(-2)). RESULTS: Thirty-four subjects were found to be carrying the +62G-->A polymorphism in the control and 24 in the diabetic group (allelic frequencies 4% and 3.2% respectively). Subjects with DM-2 were not found to have a different frequency of the genotypes (93.75% and 6.258%, for GG:GA/AA respectively) than the control subjects (92.2% and 7.8% for GG:GA/AA respectively) (OR 0.75, 95% CI 0.44-1.3, P = 0.31). In the total cohort, carriers of the A allele had a higher prevalence of hypertension (OR 1.82, 95% CI 1.03-3.21, P = 0.039). When analysed separately, the control group showed a strong association between the presence of the A allele and hypertension (OR 2.92, 95% CI 1.38-6.15, P = 0.005), whilst no such association could be established in the diabetic group (OR 1.05, 95% CI 0.43-2.54, P = 0.92). Multiple regression analysis confirmed that the presence of the A variant is associated with hypertension in control but not in diabetic subjects, independent of age and BMI. The polymorphism had no significant influence on the presence of atherosclerotic disease, BMI, and on triglyceride, HDL and LDL cholesterol levels, both, in the control and the diabetic groups. There was no difference in the serum resistin levels between the 62G-->A variant carriers and noncarriers. CONCLUSIONS: In conclusion, the present data suggest that in a German Caucasian population the +62G-->A polymorphism of the resistin gene is associated with hypertension but not with DM-2.     

抵抗素基因+299G/A多态性与T2DM并高血压病的相关性

目的研究抵抗素基因＋299G／A多态性与中国北方地区汉族人群2型糖尿病（T2DM）并高血压病的关系。方法采用聚合酶链式反应-限制性片段长度多态性技术检测北方地区汉族人群261例T2DM患者的抵抗素基因内含子2区299G／A突变。结果T2DM组GG、GA、AA基因型及G／A等位基因频率与非T2DM组比较有显著统计学差异（P〈0．01）；T2DM组GG基因型携带者空腹血糖明显高于AA基因型携带者（P〈0．05）。多元线性逐步回归分析显示，抵抗素基因＋299G／A与收缩压、舒张压无明显相关性。结论抵抗素基因＋299G／A多态性与T2DM有关．与高血压病元明显相关性。     

Resistin gene polymorphisms and progression of glycaemia in southern Chinese: a 5-year prospective study

OBJECTIVE: Human resistin gene (RETN) polymorphisms have been found to be associated with type 2 diabetes (T2DM), insulin resistance and/or obesity. We evaluated, in a 5-year prospective study, whether RETN polymorphisms could predict the progression of glycaemia in southern Chinese. DESIGN AND PATIENTS: We conducted a systematic search for variants in RETN in 70 southern Chinese subjects. This was followed by the genotyping in 624 unrelated nondiabetic subjects of two polymorphisms, -420C-->G and +62G-->A, previously reported in cross-sectional studies to be associated with T2DM in Asians, to examine their relationship with the progression of glycaemia in this cohort. RESULTS: We identified 15 polymorphisms, including 2 novel but rare polymorphisms (-319G-->A and +63G-->C). Compared to subjects with the CC genotype, -420GG subjects had higher 2-h glucose (7.7 +/- 1.8 vs. 7.2 +/- 2.0 mmol/l, P = 0.011) and insulin (101.6 +/- 69.5 vs. 79.8 +/- 59.5 mU/l, P = 0.021) during an oral glucose tolerance test. Carriers of the +62A allele had higher body mass indices (25.3 +/- 4.0 vs. 24.5 +/- 3.6 kg/m(2) in GG, P = 0.02). The presence of the allele -420G (OR 2.15, 95% CI 1.28-3.60, P = 0.004) or +62A (OR1.86, 95% CI 1.08-3.21, P = 0.025) predicted the progression of glycaemia at Year 5, after adjustment for sex, age or body mass index. The haplotype G-A also conferred a higher risk of progression in glycaemia (P = 0.002). CONCLUSION: Our study would support the role of the resistin gene in obesity, insulin resistance and progression of glycaemia in southern Chinese.     

Association of Resistin Gene 3'-Untranslated Region EX4-44G-->A Polymorphism with Obesity- and Insulin-Related Phenotypes in Turkish Type 2 Diabetes Patients

Resistin, an adipocyte-secreted hormone, has been associated with obesity, insulin resistance and type 2 diabetes mellitus (T2DM) in some, but not all, rodent models. In humans, the exact function of resistin is unkown. Because 3'-untranslated region (3'-UTR) single nucleotide substitutions (SNPs) have been shown to affect gene expression, we examined the EX4-44G-->A SNP in the 3'-UTR of exon 3 within the resistin gene. The objective of this study was to investigate, for the first time in a Turkish study group, whether the 3'-UTR EX4-44G-->A variation in the resistin gene influences the development of T2DM, obesity and insulin-related phenotypes. We analyzed the genotype frequencies of the EX4-44G-->A polymorphism of the resistin gene in 116 type 2 diabetic and 102 normal subjects. Serum lipids, obesity-related and insulin-related phenotypes were analyzed. No significant difference for genotypic frequencies were observed for the BseRI restriction site in type 2 diabetic patients as compared to controls. Waist-to-hip ratio, BMI, body fat and apoAI levels were found to be affected by resistin genotype. In the control group, BMI (p < 0.01), HIS (p < 0.05) and BF (p < 0.05) levels were found to be elevated, whereas HOMA beta-cell index (p < 0.01) and apo AI (p < 0.05) levels were found to be decreased in GG genotype carriers. In the diabetic group, the GG genotype carriers were found to have higher BMI levels (p < 0.001), waist-to-hip ratio (p < 0.05), body fat (p < 0.01), HOMA (p < 0.001) and fasting insulin (p < 0.05), but lower HbA1c levels in comparison to GC + AA carriers. These data suggest that, in the Turkish study group, the EX4-44G-->A polymorphism of the resistin gene is associated with insulin and obesity-related phenotypes.     

The codon 17 polymorphism of the CTLA4 gene in type 2 diabetes mellitus

Several studies have demonstrated an association of CTLA4 (IDDM12) alanine-17 with type 1 diabetes, but CTLA4 variants have not yet been investigated in type 2 diabetes. The CTLA4 exon 1 polymorphism (49 A/G) was analyzed in 300 Caucasian patients with type 2 diabetes and 466 healthy controls. All patients were negative for glutamate decarboxylase and islet cell antibodies. CTLA4 alleles were defined by PCR, single-strand conformational polymorphism, and restriction length fragment polymorphism analysis using BBV:I. The distribution of alleles as well as the genotypic and phenotypic frequencies were similar among patients and controls [AA, 42 vs. 39%; AG, 47 vs. 46%; GG, 11 vs. 15%, P = not significant (n.s.); A/G, 65/35% vs. 62/38%, P = n.s.; alanine/threonine 92/58% vs. 85/61%, P = n.s.]. However, detailed analysis of clinical and biochemical parameters revealed a tendency of GG (alanine/alanine) toward younger age at disease manifestation (46.8 +/- 0.8 vs. 49.5 +/- 0.8 yr, mean +/- SEM), lower body mass index (21.4 +/- 0.5 vs. 24.4 +/- 0.5 kg/m(2), P = 0.042), and basal C-peptide level (0.33 +/- 0.07 vs. 0.53 +/- 0.07nmol/L), as well as earlier start of insulin treatment (5.8 +/- 1.2 vs. 8.7 +/- 0.6 yr) and higher portion of patients on insulin (71 vs. 61%). Patients with the AA genotype were significantly less likely to develop microangiopathic lesions (P < 0.0005). No differences were found for hypertension or family history of type 2 diabetes. In conclusion, CTLA4 alanine-17 does not represent a major risk factor for type 2 diabetes. Additional studies on larger groups and different ethnic groups are warranted to clarify the association of the GG genotype with faster ss-cell failure and the lower rate of microvascular complications in AA carriers.     

Gender-specific differences in the association of adiponectin gene polymorphisms with body mass index

OBJECTIVE: Adiponectin gene polymorphisms are associated with obesity, metabolic syndrome and type 2 diabetes (T2D). The study evaluated possible associations of +45T/G and -11391G/A adiponectin gene polymorphisms with body mass index (BMI), waist circumferences (WC), and blood pressure in diabetic and non-diabetic Iranians. METHODS: This cross-sectional study involved two groups of subjects: 243 diabetic patients and 173 non-diabetic subjects recruited from Rafsanjan city in the south-east of Iran. RESULTS: No significant association was found between +45T/G and -11391G/A adiponectin gene polymorphisms and systolic or diastolic blood pressure. However, male carriers of the TT genotype of +45T/G had a significantly higher mean BMI than male GG homozygotes (p = 0.018). Also, male carriers of the GG genotype of -11391G/A had significantly higher mean BMI than male GA or AA homozygotes (p = 0.041). Female carriers of the GG genotype of -11391G/A had significantly higher mean WC than female GA or AA homozygotes (p = 0.038). CONCLUSIONS: We observed a significantly higher BMI in women, and GA or AA carriers of -11391G/A polymorphism. Also, there was a significantly lower WC in females and GG carriers of +45T/G. These results point to a gender-specific impact of the studied genotypes on BMI and WC.     

Effect of polymorphisms in the PPARGC1A gene on body fat in Asian Indians

OBJECTIVE: To evaluate whether polymorphisms in the peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PPARGC1A) gene were related to body fat in Asian Indians. METHODS: Three polymorphisms of PPARGC1A gene, the Thr394Thr, Gly482Ser and +A2962G, were genotyped on 82 type 2 diabetic and 82 normal glucose tolerant (NGT) subjects randomly chosen from the Chennai Urban Rural Epidemiology Study using PCR-RFLP, and the nature of the variants were confirmed using direct sequencing. Linkage disequilibrium (LD) was estimated from the estimates of haplotypic frequencies using an expectation-maximization algorithm. Visceral, subcutaneous and total abdominal fat were measured using computed tomography, whereas dual X-ray absorptiometry was used to measure central abdominal and total body fat. RESULTS: None of the three polymorphisms studied were in LD. The genotype (0.59 vs 0.32, P=0.001) and allele (0.30 vs 0.17, P=0.007) frequencies of Thr394Thr polymorphism were significantly higher in type 2 diabetic subjects compared to those in NGT subjects. The odds ratio for diabetes (adjusted for age, sex and body mass index) for the susceptible genotype, XA (GA+AA) of Thr394Thr polymorphism, was 2.53 (95% confidence intervals: 1.30-5.04, P=0.009). Visceral and subcutaneous fat were significantly higher in NGT subjects with XA genotype of the Thr394Thr polymorphism compared to those with GG genotype (visceral fat: XA 148.2+/-46.9 vs GG 106.5+/-51.9 cm(2), P=0.001; subcutaneous fat: XA 271.8+/-167.1 vs GG 181.5+/-78.5 cm(2), P=0.001). Abdominal (XA 4521.9+/-1749.6 vs GG 3445.2+/-1443.4 g, P=0.004), central abdominal (XA 1689.0+/-524.0 vs GG 1228.5+/-438.7 g, P<0.0001) and non-abdominal fat (XA 18763.8+/-8789.4 vs GG 13160.4+/-4255.3 g, P<0.0001) were also significantly higher in the NGT subjects with XA genotype compared to those with GG genotype. The Gly482Ser and +A2962G polymorphisms were not associated with any of the body fat measures. CONCLUSION: Among Asian Indians, the Thr394Thr (G --> A) polymorphism is associated with increased total, visceral and subcutaneous body fat.     

瘦素受体基因Lys109Arg多态性与非酒精性脂肪性肝病的关系

目的探讨瘦素受体基因Lys109Arg多态性与非酒精性脂肪性肝病(NAFLD)的关系。方法收集180 例接受体检的成年人,分成2组:(1)NAFLD组117例,男77例,女40例,平均年龄(50．4±13．1)岁;(2)对照组63例,男32例,女31例,平均年龄(49．1±14．5)岁。同时测定身高、体重、臀围、腰围、腹壁脂肪厚度、体脂含量、血压。入选对象均签署知情同意书。试验对象进行空腹采血,血标本用于检测丙氨酸氨基转移酶、甘油三酯、高密度脂蛋白和血糖水平。结果NAFLD患者和正常对照组LEPR基因Lys109Lys、Lys109Arg和Arg109Arg多态性分布差异无统计学意义(x2=1．409,P=0．494)。腹壁脂肪厚度LEPR基因Lys109Lys携带者平均为(4．1± 0．4)cm,Lys109Arg平均为(2．8±0．6)cm,Arg109Arg平均为(2．7±0．7)cm,LEPR基因Lys109Lys携带者明显高于Lys109Arg和Arg109Arg携带者,差异有统计学意义(F 5．197,P=0．006)。血清胆固醇水平LEPR 基因Lys109Lys携带者平均为(5．1±0．4)mmol／L,Lys109Arg平均为(25．5±6．9)mmol／L,Arg109Arg平均为(27．2±8．4)mmol／L,LEPR基因Lys109Lys携带者明显降低,差异有统计学意义(F=8．164,P=0．005)。结论瘦素受体基因Lys109Arg多态性可能参与腹壁脂肪的分布和胆固醇代谢的调节,至于是否参与NAFLD的发病机制尚待进一步研究。     

Klotho gene promoter polymorphism and cognitive impairment

Aim:   To study the association between the klotho gene polymorphism and cognitive impairment in community-living men and women.
Methods:   The subjects consisted of 2234 community-living Japanese men and women aged 40–79 years. The klotho gene promoter polymorphism G- 395 A was identified and cognitive function was assessed using the Japanese Wechsler Adult Intelligence Scales – Revised Short Forms ( JWAIS-R SF) and Mini-Mental State Examination (MMSE). Brain infarction and atrophy were assessed by brain magnetic resonance imaging (MRI). The differences in cognitive function, infarction and atrophy were compared between the GG type and GA/AA type of the klotho gene G- 395 A polymorphism.
Results:   The distribution of the klotho gene G- 395 A polymorphism was GG 1639 (73.4%), GA 539 (24.1%), and AA 56 (2.5%). There was no significant difference in intelligence quotient (IQ) between the GG type and GA/AA type in the subjects aged 40–59 years. However, the IQ level was significantly different in terms of the klotho genotype for subjects aged 60–79 years ( P  = 0.004). The mean and SE of IQ levels of the subjects with the GG type and the GA/AA type at nucleotide −395 were 99.8 ± 0.5 and 102.6 ± 0.8, respectively. There were also significant differences in three subtests of JWAIS-R SF – Information, Similarities, and Picture Completion – for subjects aged 60–79 years. Also, the MMSE score was slightly lower for the GG type than for the GA/AA type ( P  = 0.099). However, there were no differences in the findings of brain MRI.
Conclusion:   There were statistically significant differences in cognitive function for klotho gene promoter polymorphism G- 395 A only in subjects aged 60 or over. This polymorphism may be associated with age-related cognitive impairment.     

The absence of evidence for major effects of the frequent SNP +299G>A in the resistin gene on susceptibility to insulin resistance syndrome associated with Japanese type 2 diabetes

Resistin, specifically secreted from adipocytes, antagonizes insulin and represents a promising candidate gene for type 2 diabetes. We reported that a frequent single nucleotide polymorphism (SNP) +299G>A in this gene is not associated with type 2 diabetes. To determine whether this SNP affects insulin resistance syndrome associated with type 2 diabetes, we examined its effects on susceptibility to obesity, hyperlipidemia and hypertension in type 2 diabetic subjects and on susceptibility to type 2 diabetes by interaction with other frequent genes involved in lipid metabolism, namely, beta3-adrenergic receptor (b3AR) Trp64Arg, phosphodiesterase 3B (PDE3B) c.1389G>A or lysosomal acid lipase (LAL) Thr-6Pro. The 99 type 2 diabetic and 99 control subjects were typed by PCR direct sequencing or PCR-RFLP. No differences in frequencies of obesity, hyperlipidemia and hypertension were found between the type 2 diabetic subjects with G/G and those with G/A or A/A genotypes of the resistin SNP. When the combination of the resistin SNP with each of b3AR, PDE3B and LAL SNPs was assessed, no association with type 2 diabetes was evident. Therefore, the frequent SNP +299G>A in the resistin gene is unlikely to have major effects on susceptibility to insulin resistance syndrome associated with type 2 diabetes in Japanese subjects.     

-308 Nco I polymorphism of tumour necrosis factor alpha in overweight Caucasians

We investigated whether a polymorphism in the promoter region of the TNFalpha gene (-308 A/G) is associated with reduced weight loss in obese Australian subjects on an energy restricted diet. 189 healthy subjects and 91 subjects with type II diabetes were genotyped for the -308 Nco I polymorphism using PCR-RFLP techniques. A subset of these subjects (211 females and 45 males), were placed on a 30% energy restricted diet (6200 kJ) for 12 weeks. Subjects were assessed every 2 weeks and changes in body weight, waist circumference and BMI were used as determinants of weight loss. Fasting plasma was analysed for glucose, insulin, lipids and free fatty acids. 64% of subjects were GG homozygotes, 31% were AG heterozygotes and 5% were AA homozygotes. There was no significant difference between the allele frequency in healthy subjects (0.21) and type 2 diabetic patients (0.24). The presence of the -308 A/G polymorphism did not significantly influence initial BMI, the amount of weight lost (GG, 8.1+/-0.65 kg, AG, 6.9+/-0.77 kg, AA, 7.6+/-0.12 kg), waist circumference or any metabolic variable. The AA variant at position -308 in the promoter region of the TNFalpha gene does not influence the amount of weight lost in overweight and obese men and women on a 30% energy restricted diet.     

Association between COX-2-1195G>A polymorphism and gastrointestinal cancer risk: A meta-analysis

AIM To perform a meta-analysis to investigate the association between cyclooxygenase-2(COX-2)-1195GA gene polymorphism and gastrointestinal cancers. METHODS Publications related to the COX-2-1195GA gene polymorphism and gastrointestinal cancers published before July 2016 were retrieved from Pub Med, EMBASE, Web of Science, China Biological Medicine Database, China National Knowledge Infrastructure, and CQVIP Database. Meta-analysis was performed using Stata11.0 software. The strength of the association was evaluated by calculating the combined odds ratios(ORs) and the corresponding 95%CIs. The retrieved publications were excluded or included one by one for sensitivity analysis. In addition, the funnel plot, Begg's rank correlation test, and Egger's linear regression method were applied to analyse whether the included publications had publication bias. RESULTS A total of 24 publications related to the COX-2-1195GA gene polymorphism were included, including 28 studies involving 11043 cases and 18008 controls. The meta-analysis results showed that the COX-2-1195GA gene polymorphism significantly correlated with an increased risk of gastrointestinal cancers, particularly gastric cancer(A vs G: OR = 1.35; AA/AG vs GG: OR = 1.54; AA vs GG/AG: OR = 1.43; AA vs GG: OR = 1.80; AG vs GG: OR = 1.35). Compared to the Caucasian population in America and Europe, the COX-2-1195GA gene polymorphism in the Asian population(A vs G: OR = 1.30; AA/AG vs GG: OR= 1.50; AA vs GG/AG: OR = 1.35; AA vs GG: OR = 1.71; AG vs GG: OR = 1.37) significantly increased gastrointestinal cancer risk. The sensitivity analysis(P 0.05) and the false positive report probability(P 0.2) confirmed the reliability of the results. CONCLUSION The results showed that the COX-2-1195GA gene polymorphism might be a potential risk factor for gastrointestinal cancers. Further validation by a large homogeneous study is warranted.     

Resistin and type 2 diabetes: regulation of resistin expression by insulin and rosiglitazone and the effects of recombinant resistin on lipid and glucose metabolism in human differentiated adipocytes

Resistin, an adipocyte secreted factor, has been suggested to link obesity with type 2 diabetes in rodent models, but its relevance to human diabetes remains uncertain. Although previous studies have suggested a role for this adipocytokine as a pathogenic factor, its functional effects, regulation by insulin, and alteration of serum resistin concentration by diabetes status remain to be elucidated. Therefore, the aims of this study were to analyze serum resistin concentrations in type 2 diabetic subjects; to determine the in vitro effects of insulin and rosiglitazone (RSG) on the regulation of resistin, and to examine the functional effects of recombinant human resistin on glucose and lipid metabolism in vitro. Serum concentrations of resistin were analyzed in 45 type 2 diabetic subjects and 34 nondiabetic subjects. Subcutaneous human adipocytes were incubated in vitro with insulin, RSG, and insulin in combination with RSG to examine effects on resistin secretion. Serum resistin was increased by approximately 20% in type 2 diabetic subjects compared with nondiabetic subjects (P = 0.004) correlating with C-reactive protein. No other parameters, including adiposity and fasting insulin levels, correlated with serum resistin in this cohort. However, in vitro, insulin stimulated resistin protein secretion in a concentration-dependent manner in adipocytes [control, 1215 +/- 87 pg/ml (mean +/- SEM); 1 nM insulin, 1414.0 +/- 89 pg/ml; 1 microM insulin, 1797 +/- 107 pg/ml (P < 0.001)]. RSG (10 nM) reduced the insulin-mediated rise in resistin protein secretion (1 nM insulin plus RSG, 971 +/- 35 pg/ml; insulin, 1 microM insulin plus RSG, 1019 +/- 28 pg/ml; P < 0.01 vs. insulin alone). Glucose uptake was reduced after treatment with 10 ng/ml recombinant resistin and higher concentrations (P < 0.05). Our in vitro studies demonstrated a small, but significant, reduction in glucose uptake with human recombinant resistin in differentiated preadipocytes. In human abdominal sc adipocytes, RSG blocks the insulin-mediated release of resistin secretion in vitro. In conclusion, elevated serum resistin in human diabetes reflects the subclinical inflammation prevalent in type 2 diabetes. Our in vitro studies suggest a modest effect of resistin in reducing glucose uptake, and suppression of resistin expression may contribute to the insulin-sensitizing and glucose-lowering actions of the thiazolidinediones.     

Tumor necrosis factor [alpha ] -238 and -308 polymorphisms do not associate with insulin resistance in hypertensive subjects

It is well established that, as a group, patients with essential hypertension are characterized by insulin resistance. Previous studies have shown that a biallelic polymorphism in the tumor necrosis factor (TNF)alpha promoter position -308 and -238 might be involved in the insulin resistance state in diabetic and/or nondiabetic subjects. We determined these polymorphisms in 235 nondiabetic hypertensive subjects and 246 unrelated normotensive controls. Fasting plasma glucose, insulin, lipoprotein, leptin, and TNFalpha concentrations were measured, in addition to plasma glucose and insulin responses to a 75-g oral glucose tolerance test (OGTT). Insulin sensitivity was also determined by an insulin suppression test in 69 hypertensive and 76 normotensive individuals. The results showed no association of these genotypic distributions between hypertensive and normotensive individuals both at -308 (GG, GA, and AA were 80.9%, 17.9%, and 1.3% in hypertensives, 84.2%, 15.4%, and 0.4% in normotensives, chi(2) = 1.68, P =.432) and at -238 (GG, GA, and AA were 98.3%, 1.7%, and 0% in hypertensives, 96.7%, 3.3%, and 0% in normotensives, chi(2) = 1.19, P =.276) sites. These results did not change even after adjustment for values of age and body mass index (BMI). Anthropometric measurements, fasting plasma glucose, insulin, lipoprotein concentrations, glucose, and insulin responses to OGTT, TNFalpha, and leptin concentrations were similar between the genotype at the -308 site both in hypertensive and normotensive groups. Insulin sensitivity, either measured by an insulin suppression test or homeostasis model assessment (HOMA) index, did not differ between the genotype at the -308 site in subjects with hypertension or normotension. Fasting plasma TNFalpha (10.2 alpha 0.5 pg/mL v 10.1 +/- 0.5 pg/mL, P =.928) concentrations did not differ between hypertensive and normotensive subjects even after adjustment for body fat and BMI values. We conclude that TNFalpha promoter gene polymorphisms at position -238 and -308 do not play a major role in the pathogenesis of insulin resistance in Chinese subjects with or without hypertension.     

北京地区汉族妇女瘦素受体基因Gln223Arg多态性和骨密度的关系

目的　探讨瘦素受体基因Gln2 2 3Arg多态性与青年妇女骨峰值和绝经后骨质疏松妇女骨密度的关系。方法　筛选 2 19例健康青年妇女和 10 2例绝经后骨质疏松妇女 ,用双能X线吸收测定法检测研究对象腰椎和髋部的骨密度 ,用PCR 限制性片段长度多态性分析方法检测研究对象的瘦素受体基因Gln2 2 3Arg的基因型。 结果　本研究人群中瘦素受体基因Gln2 2 3Arg基因型及基因频率的分布符合Hardy Weinberg定律 ,提示本研究人群是一个平衡群体。青年妇女组瘦素受体基因Gln2 2 3Arg的GG基因型组腰椎 2～ 4的骨密度高于GA和AA基因型组 [(1.2 13± 0 .12 7) g/cm2 比(1.15 4± 0 .12 4 ) g/cm2 ,P <0 .0 5 ],在股骨颈、Ward三角区、大转子部位各基因型组间骨密度值无统计学差异 ;10 2例绝经后骨质疏松妇女中LEPR基因Gln2 2 3Arg各基因型组间在腰椎 2～ 4、股骨颈、Ward三角区、大转子部位的骨密度值均无统计学差异。偏相关分析进一步表明青年妇女组的瘦素受体基因多态性与腰椎 2～ 4的骨密度相关 (r =- 0 .15 1,P <0 .0 5 )。结论　瘦素受体基因Gln2 2 3Arg的多态性与青年妇女腰椎 2～ 4骨峰值的获得和维持有关 ,可能是骨峰值独立的影响因素 ,等位基因G可能是骨量的保护因子 ,可作为预测汉族妇女骨质疏松发生危险性的遗传     

A single-nucleotide polymorphism in C-type natriuretic peptide gene may be associated with hypertension.

We conducted an association study between genetic variants of C-type natriuretic peptide gene (CNP) and hypertension in a Japanese population. We found four genetic variants, two in the promoter region, one missense mutation, and one in the 3'-untranslated region (3'-UTR), and genotyped all four variants in 2,006 subjects recruited from the Suita study. One of the variants, G2628A in 3'-UTR, was found to be associated with blood pressure. Multiple logistic analyses indicated that the genotype of the G2628A polymorphism (GG=1, GA+AA=2) (p=0.0034), sex (p=0.0288), alcohol consumption (p=0.0002), age (p<0.0001), and body mass index (p<0.0001) were predictors of hypertension. The odds ratio of the GA+AA genotype over the GG genotype for hypertension was 1.40 (p=0.0034, 95% confidence interval (CI) 1.12-1.75). Multiple logistic analyses in a younger subpopulation aged below 65 years indicated that the odds ratio of the GA+AA genotype over the GG genotype for hypertension was 1.58 (p=0.0024, 95%CI 1.18-2.12). Thus, the CNP G2628A polymorphism made an even greater contribution to hypertension in the younger subpopulation.     

Association of CTLA-4 polymorphism with positive anti-GAD antibody in Japanese subjects with type 1 diabetes mellitus

OBJECTIVE: CTLA-4, expressed on activated T cells, is thought to be a negative regulator of T cell function. Its gene (2q33) may confer genetic susceptibility to type 1 diabetes mellitus (IDDM12). The present study was undertaken to clarify the role of CTLA-4 gene polymorphism in Japanese subjects with type 1 diabetes and its effect on their clinical features. SUBJECTS AND METHODS: In 117 Japanese subjects with type 1 diabetes, the CTLA-4 exon 1 polymorphism (49 A/G) was defined by PCR-RFLP analysis. Anti-GAD antibodies (GAD-Ab) and fasting serum C-peptide were also determined. 141 healthy age- and sex-matched subjects served as controls. RESULTS: The frequency of each polymorphism was not different between the type 1 diabetic subjects and the controls; AA 21, AG 42 and GG 54 for the diabetic subjects, and AA 22, AG 47 and GG 72 for the controls. The frequency of the GG genotype was higher in the diabetic subjects with positive GAD-Ab (greater than 8 U/ml) (67%) than in the GAD-Ab negative subjects (39%) (P < 0.05). The prevalence of positive GAD-Ab declined with the duration of diabetes. In the diabetic subjects with disease duration of less than 5 years (n = 40), the frequency of the GG genotype was also higher in the GAD-Ab positive subjects (71%) (P < 0.05). In the analysis of all the diabetic subjects, there was a strong association between positive GAD-Ab and beta cell function (P < 0.0001). CONCLUSIONS: There was no evidence that the CTLA-4 exon 1 polymorphism (49 A/G) confers genetic susceptibility to type 1 diabetes mellitus in our case-control study in Japanese subjects. However, the frequency of positive GAD-Ab was higher in the GG subjects. CTLA-4 polymorphism might contribute to the clinical heterogeneity of type 1 diabetes mellitus in Japanese subjects.     

The G1057D polymorphism of IRS-2 gene and its relationship with obesity in conferring susceptibility to type 2 diabetes in Asian Indians

OBJECTIVE: To investigate the association of insulin receptor substrate-2 (IRS-2) G1057D polymorphism with type 2 diabetes and obesity in Asian Indians. METHODS: The study comprised of 1193 normal glucose tolerant (NGT) subjects and 1018 subjects with type 2 diabetes, aged >/=20 years with an average body mass index of 23.7+/-4.6 and 25.3+/-4.2 kg/m(2), respectively. The subjects were unrelated and randomly selected from the Chennai Urban Rural Epidemiology Study (CURES), a population-based study in Chennai in southern India. The G1057D polymorphism of the IRS-2 gene was genotyped using PCR-RFLP assay. RESULTS: The genotype frequency of the IRS-2 G1057D polymorphism was significantly different between the NGT and type 2 diabetic groups (P=0.0007) in the total study subjects and among the obese subjects (P=0.00007). Logistic regression analysis showed that the DD genotype showed an increased susceptibility to diabetes with an odds ratio (adjusted for age and sex) of 2.19 (95% CI: 1.34-3.57, P=0.002) when compared to the GG+GD genotype, among the obese subjects, but not in non obese subjects. In order to explore possible interaction with obesity, logistic regression analysis was performed and the coefficient corresponding to the interaction parameter (genotype x obesity) was significant (P=0.0001). CONCLUSION: In Asian Indians, the DD genotype increases susceptibility to type 2 diabetes by interacting with obesity.     

Hyperresistinemia is associated with coexistence of hypertension and type 2 diabetes

Numerous studies have demonstrated that high blood pressure substantially increases the risk of microvascular and macrovascular complications in patients with type 2 diabetes mellitus (T2DM). Currently, we found that serum resistin, an adipocyte- and monocyte-derived cytokine, was positively correlated with several components of the metabolic syndrome, including hypertension in T2DM. To investigate the association of resistin with an etiologic difference among subjects with hypertension with T2DM, hypertension without T2DM, and normotensive T2DM, we analyzed 210 subjects, including 91 with hypertension with T2DM, 55 with hypertension without T2DM, and 64 with normotensive T2DM. Serum resistin level was higher in subjects with hypertension with T2DM, followed by subjects with normotensive T2DM and hypertension without T2DM, irrespective of antihypertensive treatment status (20.9+/-17.6 and 14.0+/-8.9 versus 11.2+/-7.6 ng/mL, respectively; P<0.01). Simple regression analysis revealed that resistin positively correlated with blood pressure (systolic blood pressure: r=0.29, P<0.01; diastolic blood pressure: r=0.21, P<0.05) and intima-media thickness (r=0.27; P<0.05) in patients with T2DM but not in subjects with hypertension without T2DM. Multiple regression analysis, adjusted for age, gender, body mass index, fasting glucose, high-density lipoprotein cholesterol, white blood cell counts, and glomerular filtration rate, further revealed that resistin was an independent factor for high blood pressure in patients with T2DM (P<0.05). In vitro gene expression analysis in human coronary endothelial cells revealed that resistin induced fatty acid binding protein, a key molecule of insulin resistance, diabetes, and atherosclerosis. These results suggest that hyperresistinemia would contribute to the pathogenesis of hypertension in patients with T2DM, significantly linked to vascular complications and cardiovascular events.     

瘦素受体基因Gln223Arg多态性与阻塞性睡眠呼吸暂停低通气综合征的关系

目的　探讨瘦素受体 (Lepr)基因Gln2 2 3Arg多态性与阻塞性睡眠呼吸暂停低通气综合征 (OSAHS)之间的关系。方法　采用聚合酶链反应 限制性片段长度多态性 (PCR RFLP)方法 ,测定181例中国北方地区汉族人Gln2 2 3Arg多态性的基因型 (其中OSAHS组 10 3例 ,非OSAHS对照组 78例 ) ,同时测定体重指数 (BMI)、颈围 (NC)、腰臀比 (WHR)以及醒后血压 (Bp)、醒后心率 (HR)、多导睡眠图 (PSG)。其中OSAHS组 6 0例 ,非OSAHS对照组 4 0例进行了血清空腹血糖 (FBG)、甘油三酯 (TG)、胆固醇 (Chol)、空腹真胰岛素 (TI)及血清瘦素 (Lep)的测定。结果　携带瘦素受体GG基因型的OSAHS患者颈围明显较 (GA +AA)基因型颈围大 [(41 4 6± 0 34)cmvs (39 85± 0 70 )cm ,P =0 0 31];Gln2 2 3Arg多态性与北方地区汉族人OSAHS无显著相关性 (χ2 =0 783,P =0 6 76 ) ;Gln2 2 3Arg不同基因型与OSAHS的总体脂、Bp、Lep、TI、FBG、TG、Chol及PSG各参数间不存在相关性 (P >0 0 5 )。结论　Lepr基因Gln2 2 3Arg多态性可能参与了OSAHS颈部脂肪选择性分布的调节 ,但其在北方地区汉族OSAHS的发病中可能无重要作用 ;目前的研究未发现Gln2 2 3Arg的基因型与OSAHS的BMI、高血压、FBG、TI、Lep、TG、Chol水平以及PSG参数之间存在相关性。