The Leu72Met polymorphism of the GHRL gene prevents the development of diabetic nephropathy in Chinese patients with type 2 diabetes mellitus.

The preproghrelin (GHRL) Leu72Met polymorphism (rs 696217) is associated with obesity, reduced glucose-induced insulin secretion in healthy or diabetic subjects, and reduced serum creatinine (Scr) levels in type 2 diabetes. We evaluated the association of the Leu72Met polymorphism with measures of insulin sensitivity in non-diabetic control individuals and type 2 diabetics, and whether this variation contributes to the development of diabetic nephropathy (DN) in type 2 diabetes. A case-control study was performed of 291 non-diabetic control subjects and 466 patients with type 2 diabetes, of whom 238 had DN with overt albuminuria (DN group; albuminuric excretion rate [AER] ≥ 300 mg/24 h) and 228 did not have DN, but had diabetes for more than 10 years (non-DN group). Genotyping was performed using a TaqMan PCR assay. The Leu/Leu, Leu/Met, and Met/Met genotype frequencies were significantly different between the non-DN and DN groups (p = 0.011). The frequency of the variant genotypes (Leu/Met, Met/Met) was significantly lower in the DN group than the non-DN group (23.5 vs. 36.0 %, p = 0.003). Met/Met non-diabetic control subjects had lower BMI and Scr levels and higher eGFR level than Leu/Leu or Leu/Met individuals (p < 0.05). Leu/Met and Met/Met type 2 diabetics had significantly lower AER and Scr levels and higher eGFR level than Leu/Leu type 2 diabetics (all p < 0.001). The GHRL Leu72Met polymorphism may help to maintain normal renal function and may protect against the development of DN by reducing albuminuria and improving renal function in Chinese patients with type 2 diabetes.

Mutations in KCNJ11 are associated with the development of autosomal dominant, early-onset type 2 diabetes.

AIMS/HYPOTHESIS: More than 90% of Chinese familial early-onset type 2 diabetes mellitus is genetically unexplained. To investigate the molecular aetiology, we identified and characterised whether mutations in the KCNJ11 gene are responsible for these families. METHODS: KCNJ11 mutations were screened for 96 familial early-onset type 2 diabetic probands and their families. Functional significance of the identified mutations was confirmed by physiological analysis, molecular modelling and population survey. RESULTS: Three novel KCNJ11 mutations, R27H, R192H and S116F117del, were identified in three families with early-onset type 2 diabetes mellitus. Mutated KCNJ11 with R27H or R192H markedly reduced ATP sensitivity (E23K>R27H>C42R>R192H>R201H), but no ATP-sensitive potassium channel currents were detected in the loss-of-function S116F117del channel in vitro. Molecular modelling indicated that R192H had a larger effect on the channel ATP-binding pocket than R27H, which may qualitatively explain why the ATP sensitivity of the R192H mutation is seven times less than R27H. The shape of the S116F117del channel may be compressed, which may explain why the mutated channel had no currents. Discontinuation of insulin and implementation of sulfonylureas for R27H or R192H carriers and continuation/switch to insulin therapy for S116F117del carriers resulted in good glycaemic control. CONCLUSIONS/INTERPRETATION: Our results suggest that genetic diagnosis for the KCNJ11 mutations in familial early-onset type 2 diabetes mellitus may help in understanding the molecular aetiology and in providing more personalised treatment for these specific forms of diabetes in Chinese and other Asian patients.

Mitochondrial DNA mutations in diabetes mellitus patients in Chinese Han population.

BACKGROUND AND OBJECTIVE: Mutations of mitochondrial DNA are associated with diabetes mellitus (DM). The present case-control study aimed to investigate the mutations of mitochondrial DNA in DM patients of Chinese Han ethnicity. METHODS AND RESULTS: A total of 770 DM patients and 309 healthy control individuals were enrolled. The mitochondrial DNA was extracted from blood cells and analyzed by the polymerase chain reaction-restriction fragment length polymorphism assay. In the diabetes group, there were 13 (1.69%) individuals carrying the mt3243 A → G mutation while none of the healthy control had this mutation. Though the 14709, 3316, 3394, and 12026 mutation variants were identified in 9, 17, 18 and 28 in DM patients respectively, there were no significant differences compared with control group. And the 3256, 8296, 8344, 8363, 3426 and 12258 mutations were not detected in either group. In the diabetes group, two double mutations were identified: A3243G+T3394C and A3243G+A12026G. CONCLUSION: Our data suggested that mitochondrial gene tRNA(Leu(UUR)) 3243 A → G mutation may be one risk of prevalence of DM and associated with worse clinical status in Chinese Han population.

Serum Proteome Changes in Healthy Subjects with Different Genotypes of NOS1AP in the Chinese Population.

Type 2 diabetes and its chronic complications have become a worldwide epidemic nowadays. However, its molecular mechanism is still unknown. We have previously identified a novel variant rs12742393 of NOS1AP for type 2 diabetes susceptibility in the Chinese population. In this study, we analyzed the total serum profiling among three genotypes of rs12742393 to discover potential crosstalk under the variant and the disease through proteomic analyses for the first time. We used OFFGEL peptide fractionation, LC-MS/MS analysis, and label-free quantification to profile the fasting human serum samples of the genotypes in rs12742393 (n = 4, for CC, AC, and AA, resp.). Four proteins were identified, including apoA4, alpha1-ACT, HABP2, and keratin 10, with blood levels changed significantly between CC and AA homozygotes of rs12742393. Compared with AA group, the levels of apoA4 increased (P = 0.000265), whereas the concentration of alpha1-ACT, HABP2, and keratin 10 decreased in CC group (P = 0.011116, 0.021175, and 0.015661, resp.). Then we selected additional fasting serum samples for ELISA and western blot validation. However, no significant differences were identified by neither ELISA nor western blot (P > 0.05). The protein profiling changes between the genotypes of rs12742393 indicated that this SNP might play a role in the development of type 2 diabetes.

High serum level of fibroblast growth factor 21 is an independent predictor of non-alcoholic fatty liver disease: a 3-year prospective study in China.

BACKGROUND & AIMS: Fibroblast growth factor 21 (FGF21), a hormone predominantly secreted by the liver, has been shown to be positively associated with the severity of non-alcoholic fatty liver disease (NAFLD) in cross-sectional studies. We investigated the prospective association of FGF21 with NAFLD development in a 3-year prospective study involving a population-based cohort comprising 808 Chinese subjects. METHODS: Serum FGF21 levels at baseline and follow-up were measured using an enzyme-linked immunosorbent assay. Independent predictors of NAFLD development were identified using multiple logistic regressions. The predicting accuracy of the models was evaluated using area under the receiver-operating characteristic (ROC) curves (AUCs). RESULTS: In subjects who had progressed to NAFLD, the baseline FGF21 concentration (319.12 pg/ml [172.65, 518.78]) was significantly higher than that in subjects who did not develop NAFLD (199.10 pg/ml [123.56, 322.80]) (p <0.001). At follow-up, significant increase of FGF21 level was observed in those subjects who developed NAFLD (p <0.05). Baseline FGF21 was an independent predictor of NAFLD (OR: 7.102 [95% CI 2.488-20.270]; p <0.001), together with body mass index (BMI) (OR: 1.489 [95% CI 1.310-1.691]; p <0.001). The ROC-AUC was 0.816 (95% CI 0.766-0.867) for the FGF21 Model, which was calculated with FGF21 and BMI. FGF21 Model <0.13 can be used to rule out (sensitivity=85.71%, negative likelihood ratio=0.23) and ≥0.30 can be rule in (specificity=86.34%, positive likelihood ratio=3.66) ultrasonography-diagnosed NAFLD after 3 years. CONCLUSIONS: High serum FGF21 concentration was an independent predictor of NAFLD in humans. The FGF21 Model and its cut-offs may be useful for early diagnosis and intervention of NAFLD.

Genetic variations in APPL2 are associated with overweight and obesity in a Chinese population with normal glucose tolerance.

BACKGROUND: APPL1 and APPL2 are two adaptor proteins, which can mediate adiponectin signaling via binding to N terminus of adiponectin receptors in muscle cells. Genes encoding adiponectin and adiponectin receptors contribute to insulin resistance and the risk of obesity, and genetic variants of APPL1 are associated with body fat distribution. However, the association between genetic variations of APPL2 and metabolic traits remains unknown. In the current study, we aimed to test the impacts of APPL2 genetic variants on obesity in a Chinese population with normal glucose tolerance. METHODS: We genotyped six single nucleotide polymorphisms (SNPs) in APPL2 in 1,808 non-diabetic subjects. Overweight and obesity were defined by body mass index (BMI). Obesity-related anthropometric parameters were measured, including height, weight, waist circumference, hip circumference. BMI and waist-hip ratio (WHR) were calculated. RESULTS: We found significant evidence of association with overweight/obesity for rs2272495 and rs1107756. rs2272495 C allele and rs1107756 T allele both conferred a higher risk of being overweight and obese (OR 1.218, 95% CI 1.047-1.416, p = 0.011 for rs2272495; OR 1.166, 95% CI 1.014-1.341, p = 0.031 for rs1107756). After adjusting multiple comparisons, only the effect of rs2272495 on overweight/obesity remained to be significant (empirical p = 0.043). Moreover, we investigated the effects of these SNPs on obesity-related quantitative traits in all participants. rs2272495 was associated with BMI (p = 0.015), waist circumference (p = 0.006), hip circumference (p = 0.025) as well as WHR (p = 0.047) under a recessive model. Similar associations were found for rs1107756 except for WHR. CONCLUSION: This study suggests that genetic variations in APPL2 are associated with overweight and obesity in Chinese population with normal glucose tolerance.

Associations of common variants at APLN and hypertension in Chinese subjects with and without diabetes.

BACKGROUND: Apelin, the endogenous ligand for the APJ receptor, has a potent hypotensive effect via a nitric oxide-dependent mechanism in vivo. The aim of the study was to investigate the association between the common variants of apelin gene (APLN) and hypertension, which was reported recently in a Chinese Han population with and without diabetes. METHODS: Three single nucleotide polymorphisms (SNPs) on APLN were genotyped in 3156 diabetic patients and 3736 nondiabetic individuals. For non-diabetic subjects, 1779 were enrolled in stage 1 and 1757 were recruited for validation. A meta-analysis combining the two stages was carried out to obtain the overall effect. RESULTS: In diabetic patients, no significant associations of the three SNPs with hypertension were observed. In contrast, we found that rs2235306 was associated with hypertension in non-diabetic males after adjusting for covariates (OR = 1.19, P = 0.039) while rs2235307 and rs3115759 displayed no evidence of association in both genders. One haplotype, C-C-A, also showed an association with hypertension (OR = 1.47, P = 0.032) only in men. However, analysis in stage 2 and meta-analysis did not support these findings. CONCLUSIONS: We conclude that common variants on APLN are not associated with the prevalence of hypertension in the Chinese.

Polymorphic variations in manganese superoxide dismutase (MnSOD), glutathione peroxidase-1 (GPX1), and catalase (CAT) contribute to elevated plasma triglyceride levels in Chinese patients with type 2 diabetes or diabetic cardiovascular disease.

Manganese superoxide dismutase (MnSOD), glutathione peroxidase-1 (GPX1), and catalase (CAT) provide the primary antioxidant defense system. Impaired antioxidant defense increases oxidative stress and contributes to the development of type 2 diabetes and diabetic cardiovascular disease (CVD). We preformed a case-control study in Chinese type 2 diabetes patients, to determine if the MnSOD Val16Ala (T→C), GPX1 Pro198Leu (C→T), and CAT -262C/T (C→T) functional polymorphisms contribute to the development of type 2 diabetes or diabetic CVD. Patients with type 2 diabetes (n = 168) were divided into the non-CVD group (n = 83, >10 year since diagnosis) and CVD group (n = 85, history of ischemic CVD). Genotyping was performed using PCR-restriction fragment length polymorphism (PCR-RFLP) or PCR-based direct sequencing. The genotypic distribution in the non-CVD- and CVD-group and the clinical parameters in genotypic groups were not significantly different in the three polymorphic sites, respectively. Among eight genotypic combinations, the most common TT+CC+CC genotype (59.5%) was associated with higher triglyceride levels than the TT+CT+CC genotype, the second frequent one (14.9%; 1.77 ± 0.12 vs. 1.21 ± 0.11 mmol/l, P = 0.001), and all non-TT+CC+CC genotypes (40.5%; 1.77 ± 0.12 vs. 1.43 ± 0.12 mmol/l, P = 0.048). In the CVD group, significantly elevated triglyceride levels were also observed in patients with TT+CC+CC compared to patients with TT+CT+CC (2.00 ± 0.18 vs. 1.37 ± 0.16 mmol/l, P = 0.018) or non-TT+CC+CC genotypes (2.00 ± 0.18 vs. 1.65 ± 0.19 mmol/l, P = 0.070). The common MnSOD, GPX1, and CAT TT+CC+CC genotype may contribute to hypertriglyceridemia in Chinese patients with type 2 diabetes or diabetic CVD.

Phenotypic heterogeneity in Chinese patients with hepatocyte nuclear factor-1ß mutations.

AIMS/HYPOTHESIS: The aim of this study was to investigate clinical spectrum of hepatocyte nuclear factor-1ß (HNF-1ß) mutation in Chinese diabetic patients with renal dysfunction and/or structure abnormalities. MATERIALS AND METHODS: A total of 104 diabetic patients with renal structural abnormalities and/or non-diabetic renal dysfunction were recruited and HNF-1ß mutation was screened by direct sequencing. RESULTS: Three heterozygous missense mutations including c.494G>A (p.R165H), c.662A>T (p.D221V) and c.780G>C (p.E260D) were identified. Progression of diabetes and mild decline of renal function were observed in the mutation carriers during the follow-up. The p.R165H mutation carrier had severe ß-cell dysfunction and different extrapancreatic phenotypes. Compared with type 2 diabetes and normoglycemics, the p.R165H mutation carrier had a lower basal C-peptide (0.30, 0.61±0.07 and 0.50±0.04 nmol/L for p.R165H, type 2 diabetes and normoglycemics, respectively) and low values of acute C-peptide response to arginine (0.15, 0.48±0.18 and 0.76±0.08 nmol/L for p.R165H, type 2 diabetes and normoglycemics, respectively). CONCLUSION: Patients with the HNF-1ß mutation in our population can have different pancreatic and extrapancreatic phenotypes. The exact contributions of mutations to the phenotypes await functional confirmation.

Determination of diabetic retinopathy prevalence and associated risk factors in Chinese diabetic and pre-diabetic subjects: Shanghai diabetic complications study.

BACKGROUND: The prevalence of diabetic retinopathy is not well studied in the Chinese pre-diabetic population, also known as impaired glucose regulation. Hence, we investigated the prevalence of and risk factors associated with retinopathy in diabetic and pre-diabetic subjects from Chinese communities. METHODS: A total of 3736 Chinese subjects were recruited from urban communities in Shanghai. The participants were classified as normal glucose tolerance, impaired glucose regulation (IGR) and diabetes based on the 75 g oral glucose tolerance test. The levels of diabetic retinopathy (DR) were assessed with non-mydriatic retinal photographs according to the Diabetic Retinopathy Disease Severity Scale. RESULTS: The prevalence of diabetic retinopathy in patients with diabetes and impaired glucose regulation subjects was 9.4% and 2.5%, respectively. In subjects with IGR, hypertension (odds ratio: 3.54, p = 0.028), including elevated systolic and diastolic blood pressure and obesity (odds ratio: 3.53, p = 0.028) were significantly associated with diabetic retinopathy after age and sex adjustments. The factors associated with retinopathy in diabetes included diabetes duration, blood glucose levels, glycated hemoglobin levels, and the presence of albuminuria. Diabetic retinopathy was significantly associated with fasting plasma glucose in known diabetes, whereas in newly-diagnosed subjects, diabetic neuropathy was closely correlated to postprandial plasma glucose. CONCLUSIONS: Hyperglycemia was a strong risk factor for diabetic retinopathy. In pre-diabetic subjects, diabetic retinopathy was also associated with hypertension and obesity.

Association between an increment of 30-minute postchallenge plasma glucose and urine albumin excretion exists in postmenopausal women but not in premenopausal women.

OBJECTIVE: Usually, the increment of 30-minute postchallenge plasma glucose (ΔG30-0) represents the highest glucose spike in the population with normal glucose regulation (NGR). The aim of this study was to explore the differences in ΔG30-0 and urinary albumin excretion, a marker for widespread vascular damage, between premenopausal and postmenopausal women, and the relationship between ΔG30-0 and urinary albumin excretion. METHODS: A population-based cross-sectional study, consisting of 5,289 participants aged 20 to 75 years from six different communities, was conducted in Shanghai between 2007 and 2008. We assessed postchallenge blood glucose and insulin at 0-, 30-, and 120-minute urinary albumin and creatinine. ΔG30-0 was calculated as 30-minute postchallenge glucose minus fasting plasma glucose, and the albumin-to-creatinine ratio (ACR) was used to reflect urinary albumin excretion. Among these, the data of 2,240 women with NGR were analyzed. RESULTS: (1) Postmenopausal women had higher ΔG30-0 and ACR than did premenopausal women (3.55 ± 1.52 mmol/L vs 3.21 ± 1.49 mmol/L and 6.92 [4.91-10.99] mg/g vs 6.18 [4.17-10.07] mg/g, respectively; all P < 0.001). (2) Multivariable logistic regression showed that ΔG30-0 was independently associated with increased ACR in postmenopausal women with NGR (odds ratio, 1.10; P = 0.048) but not in premenopausal women. (3) The main factor associated with ΔG30-0 was the early-phase glucose disposition index drawn from the multivariable linear regression, which explained approximately 19% and 28% of the variation of ΔG30-0 in premenopausal and postmenopausal women, respectively (both P < 0.001). CONCLUSIONS: In the NGR population, postmenopausal women have higher ΔG30-0 and ACR compared with premenopausal women. The relationship between ΔG30-0 and increased urine albumin excretion existed in postmenopausal women.

CPVL/CHN2 genetic variant is associated with diabetic retinopathy in Chinese type 2 diabetic patients.

OBJECTIVE: Diabetic nephropathy and retinopathy are two important microvascular diabetes complications with a high concordance rate in diabetic patients. A recent genome-wide association study in type 1 diabetic patients of European descent identified four loci to be associated with diabetic nephropathy. The aim of this study was to test the effects of single nucleotide polymorphisms (SNPs) from these four loci on diabetic nephropathy and retinopathy in Chinese type 2 diabetic patients. RESEARCH DESIGN AND METHODS: In stage 1, we recruited 1,276 type 2 diabetic patients, including 378 patients with diabetic nephropathy but no retinopathy, 374 patients with diabetic retinopathy but no nephropathy, 244 patients with both diabetic retinopathy and nephropathy, and 280 control subjects with diabetes for >10 years and no diabetic retinopathy or nephropathy. Fifty-five SNPs from four loci (CPVL/CHN2, FRMD3, CARS, and IRS2) were genotyped. The SNPs that showed associations to diabetic retinopathy or nephropathy were genotyped in stage 2 samples for replication. RESULTS: SNPs from CPVL/CHN2 and FRMD3 were associated with diabetic retinopathy with rs39059 and rs10868025 as the top SNPs (odds ratio [OR] 1.292, 95% CI 1.097-1.523, P = 0.0022, for rs39059; 1.201, 1.014-1.422, P = 0.0343, for rs10868025) in stage 1 samples. In stage 2 analysis, only rs39059 showed similar effect to diabetic retinopathy (OR 1.269, 0.989-1.628, P = 0.0689), and meta-analysis showed a significant association between rs39059 and diabetic retinopathy, with an OR of 1.285 (1.120-1.474, P = 0.0003). CPVL/CHN2 rs39059 was also associated with levels of diabetic retinopathy (P = 0.0007 for trend). However, no association was detected between these SNPs and diabetic nephropathy. CONCLUSIONS: In this study, we found CPVL/CHN2 rs39059 was associated with diabetic retinopathy in the Chinese type 2 diabetic patients.

Functional characterization of insulin receptor gene mutations contributing to Rabson-Mendenhall syndrome - phenotypic heterogeneity of insulin receptor gene mutations.

Rabson-Mendenhall syndrome (RMS) is a rare disorder that presents as severe insulin resistance as a result of mutations present in the insulin receptor (INSR). A Chinese girl with RMS presented with profound diabetes, hyperinsulinemia, acanthosis nigricans, hirsutism, and abnormalities of teeth and nails. Direct sequencing of the patient's INSR detected heterozygote mutations at Arg83Gln (R83Q) and Ala1028Val (A1028V), with the former representing a novel mutation. Functional studies of Chinese hamster ovary (CHO) cells transfected with wild-type (WT) and mutant forms of INSR were performed to evaluate the effects of these mutations on receptor expression and activation. Receptor expression, insulin binding activity, and phosphorylation of the R83Q variant were comparable to WT. In contrast, expression of the A1028V receptor was much lower than that of WT INSR, and impairment of insulin binding and autophosphorylation were nearly commensurate with the decrease in expression detected. Reductions in the phosphorylation of IRS-1, Akt, and Erk1/2 (60%, 40%, and 50% of WT, respectively) indicate that the A1028V receptor contributes to impaired signal transduction. In conclusion, INSR mutations associated with RMS were identified. Moreover, the A1028V mutation associated with a decrease in expression of INSR potentially accounts for loss of function of the INSR.

Non-alcoholic fatty liver disease's prevalence and impact on alanine aminotransferase associated with metabolic syndrome in the Chinese.

BACKGROUND AND AIM: Non-alcoholic fatty liver disease (NAFLD) is becoming a major public health hazard in China. The present study aimed to estimate the prevalence of NAFLD, NAFLD with abnormal serum alanine aminotransferase (ALT) levels, and determine the potential associations of ALT levels with the components of metabolic syndrome (MetS) in the absence or presence of NAFLD in Chinese adults. METHODS: A population-based cross-sectional survey was conducted with 2226 participants. Physical examinations, laboratory tests and hepatic ultrasounds were performed. Individuals were further stratified into higher or lower ALT subgroups with the upper quartiles of ALT in this population. The MetS was identified according to the criteria of the Chinese Joint Committee for Developing Chinese Guidelines (JCDCG). RESULTS: The standardized prevalence of NAFLD was 23.3% (NAFLD with abnormal ALT levels, 3.1%), 26.5% (NAFLD with abnormal ALT levels, 5.1%) in males, and 19.7% (NAFLD with abnormal ALT levels, 0.9%) in females. Multivariate logistic analysis revealed that higher ALT was significantly associated with elevated triglyceride (TG) in the non-NAFLD participants, independent of age, smoking status, drinking status, and other MetS-related measures with odds ratios (95% confidence intervals) of 3.4 (1.6-7.1) and 2.3 (1.4-3.7) in males and females, respectively. On the other hand, the higher ALT was statistically associated with elevated TG and hyperglycemia in the NAFLD cases with odds ratios of 2.2 to 2.5 (P<0.05). CONCLUSIONS: The prevalence of NAFLD has become epidemic in Shanghai adults. NAFLD combined with ALT levels may be used to identify the individuals at the different risk levels of metabolic disorders.

A common polymorphism of CYP4A11 is associated with blood pressure in a Chinese population.

Variants of the human CYP4A11, which belongs to the cytochrome P450, family 4, have been reported to be associated with hypertension in general populations. However, data in the Chinese population are limited. This study sought to assess the effect of CYP4A11 on the prevalence of hypertension and blood pressure in a Chinese population. Three tagging single nucleotide polymorphisms, rs9332982, rs4660980 and rs3890011, were genotyped in 1734 community-based participants. Individuals with secondary hypertension were excluded. Sex-pooled and sex-specific analysis for genotype-phenotype association were both conducted. We found rs9332982 T allele was nominally associated with higher prevalence of hypertension in women after adjustment for covariates (OR: 1.38, 95%CI: 1.06-1.81, P = 0.0183). The significance did not retain after Bonferroni correction. In blood pressure analysis restricted to normotensive individuals, rs4660980 was associated with both systolic (ß = -3.17, P = 0.0011) and diastolic blood pressure (ß = -1.75, P = 0.0010) in men. A common variant on CYP4A11 was associated with blood pressure in a Chinese population. Future studies are needed to confirm our findings.

Lack of association between genetic polymorphisms within DUSP12 - ATF6 locus and glucose metabolism related traits in a Chinese population.

BACKGROUND: Genome-wide linkage studies in multiple ethnic populations found chromosome 1q21-q25 was the strongest and most replicable linkage signal in the human chromosome. Studies in Pima Indian, Caucasians and African Americans identified several SNPs in DUSP12 and ATF6, located in chromosome 1q21-q23, were associated with type 2 diabetes. METHODS: We selected 19 single nucleotide polymorphisms (SNPs) that could tag 98% of the SNPs with minor allele frequencies over 0.1 within DUSP12-ATF6 region. These SNPs were genotyped in a total of 3,700 Chinese Han subjects comprising 1,892 type 2 diabetes patients and 1,808 controls with normal glucose regulation. RESULTS: None of the SNPs and haplotypes showed significant association to type 2 diabetes in our samples. No association between the SNPs and quantitative traits was observed either. CONCLUSIONS: Our data suggests common SNPs within DUSP12-ATF6 locus may not play a major role in glucose metabolism in the Chinese.

Variants from GIPR, TCF7L2, DGKB, MADD, CRY2, GLIS3, PROX1, SLC30A8 and IGF1 are associated with glucose metabolism in the Chinese.

BACKGROUND: Recent meta-analysis of genome-wide association studies in European descent samples identified novel loci influencing glucose and insulin related traits. In the current study, we aimed to evaluate the association between these loci and traits related to glucose metabolism in the Chinese. METHODS/PRINCIPAL FINDINGS: We genotyped seventeen single nucleotide polymorphisms (SNPs) from fifteen loci including GIPR, ADCY5, TCF7L2, VPS13C, DGKB, MADD, ADRA2A, FADS1, CRY2, SLC2A2, GLIS3, PROX1, C2CD4B, SLC30A8 and IGF1 in 6,822 Shanghai Chinese Hans comprising 3,410 type 2 diabetic patients and 3,412 normal glucose regulation subjects. MADD rs7944584 showed strong association to type 2 diabetes (p = 3.5×10(-6), empirical p = 0.0002) which was not observed in the European descent populations. SNPs from GIPR, TCF7L2, CRY2, GLIS3 and SLC30A8 were also associated with type 2 diabetes (p = 0.0487∼2.0×10(-8)). Further adjusting age, gender and BMI as confounders found PROX1 rs340874 was associated with type 2 diabetes (p = 0.0391). SNPs from DGKB, MADD and SLC30A8 were associated with fasting glucose while PROX1 rs340874 was significantly associated with OGTT 2-h glucose (p = 0.0392∼0.0014, adjusted for age, gender and BMI), the glucose-raising allele also showed association to lower insulin secretion. IGF1 rs35767 showed significant association to both fasting and 2-h insulin levels as well as insulin secretion and sensitivity indices (p = 0.0160∼0.0035, adjusted for age, gender and BMI). CONCLUSIONS/SIGNIFICANCE: Our results indicated that SNPs from GIPR, TCF7L2, DGKB, MADD, CRY2, GLIS3, PROX1, SLC30A8 and IGF1 were associated with traits related to glucose metabolism in the Chinese population.

[No association of vascular endothelial growth factor A gene rs9369425 polymorphism with glucose metabolism in Chinese Han population].

OBJECTIVE: To investigate the relationship between the vascular endothelial growth factor A gene (VEGFA) rs9369425 single nucleotide polymorphism (SNP) and type 2 diabetes in Chinese Han population. METHODS: One thousand eight hundred and ninety two type 2 diabetes patients and 1808 controls with normal glucose were recruited in this study. Phenotypes including body mass index, waist, waist hip ratio, plasma glucose and serum insulin levels of blood obtained both at 0 and 120 minute during standard 75-gram glucose oral glucose tolerance tests, were analyzed. Insulin resistance and beta cell function were assessed by homeostasis model assessment (HOMA-IR and HOMA-B). Genotyping was performed by time-of-light mass spectrum using a Sequenom platform. RESULTS: The frequencies of minor allele G in the diabetic patients and controls were 10.8% and 11.3% respectively. No significant difference of allele distribution was detected between the cases and controls (P=0.5086). No significant difference (P>0.05) was detected on the association between rs9369425 SNP and clinical phenotypes. CONCLUSION: VEGFA rs9369425 was not associated with type 2 diabetes in Chinese Han population. Whether there is association in any other loci in this gene remained to be investigated.

Fibroblast growth factor 21 levels are increased in nonalcoholic fatty liver disease patients and are correlated with hepatic triglyceride.

BACKGROUND & AIMS: Fibroblast growth factor 21 (FGF21), a hormone primarily secreted by the liver in response to peroxisome proliferator-activated receptor-α (PPARα) activation, has recently been shown to possess beneficial effects on lipid metabolism and hepatic steatosis in animal models. This study investigated the association of FGF21 with nonalcoholic fatty liver disease (NAFLD) in Chinese patients. METHODS: Serum FGF21 levels were determined by enzyme-linked immunosorbent assay (ELISA) in 224 NAFLD and 124 control subjects, and their association with parameters of adiposity, glucose, and lipid profiles and levels of liver injury markers was studied. Besides serum concentrations, the mRNA expression of FGF21 in the liver tissue was also quantified by real-time PCR in 17 subjects with different degrees of steatosis, and was correlated with the levels of intrahepatic lipid. The protein levels of FGF21 were determined by quantitative ELISA. RESULTS: Serum FGF21 levels in patients with NAFLD (402.38 pg/ml [242.03, 618.25]) were significantly higher than those in control subjects (198.62 pg/ml [134.96, 412.62]) (p<0.01). In human liver tissues, FGF21 mRNA expression increased with the degree of steatosis. Both FGF21 mRNA expression and serum FGF21 concentrations were positively correlated with intrahepatic triglyceride (TG) having r = 0.692 and r = 0.662, respectively, at p<0.01. Furthermore, the increased expression of FGF21 was accompanied by elevated protein levels in liver tissues. CONCLUSIONS: These results support the role of FGF21 as a key regulator of hepatic lipid metabolism in humans, and suggest that serum FGF21 can be potentially used as a biomarker for NAFLD.

Comparison of body mass index with body fat percentage in the evaluation of obesity in Chinese.

OBJECTIVE: To evaluate the present Chinese body mass index (BMI) criteria with body fat percentage (BF%) in determining obesity in Chinese population. METHODS: A total of 4 907 subjects (age: 20-90 yrs) were enrolled in the baseline survey of a longitudinal epidemiological study, and 2 638 of them were reevaluated in 5.5 years later. The Chinese BMI and WHO BF% were used to define obesity, respectively. RESULTS: The diagnostic agreement between the Chinese BMI and WHO BF% definitions for obesity was poor for both men (kappa: 0.210, 95% CI: 0.179-0.241) and women (kappa: 0.327, 95% CI: 0.296-0.358). However, BMI had a good correlation with BF% both in men (r: 0.785, P<0.01) and women (r: 0.864, P<0.01). The age and sex-adjusted relative risks (RR) for incidence of type 2 diabetes (T2DM) were significantly higher in subjects with intermediate BF% (BF%:20.1%-25% for men, 30.1%-35% for women) (RR: 2.35, 95% CI: 1.23-4.48) and high BF%(BF%>25% for men and > 35% for women)(RR: 2.89, 95% CI: 1.43-5.81), or in subjects with high BMI (BMI>or=28 kg/m(2)) (RR: 2.46, 95% CI: 1.31-4.63) when compared to those with low BF% (BF%