The n-3 long-chain PUFAs modulate the impact of the GCKR Pro446Leu polymorphism on triglycerides in adolescents

Dietary n-3 long-chain PUFAs (LC-PUFAs) are associated with improvement in the parameters of the metabolic syndrome (MetS). Glucokinase regulatory protein (GCKR) is a key protein regulating intracellular glucose disposal. Our aim was to investigate: i) the relationship between the GCKR rs1260326 (Pro446Leu) polymorphism and parameters of the MetS; and ii) a potential influence of n-3 and n-6 LC-PUFA levels on this relationship in the HELENA study (1,155 European adolescents). Linear regression analyses were performed to study the association between rs1260326 and the outcomes of interest. Interactions between rs1260326 and LC-PUFA levels on outcomes were explored. The T allele of rs1260326 was associated with higher serum TG concentrations compared with the C allele. In contrast to n-6 LC-PUFA levels, a significant interaction (P = 0.01) between rs1260326 and total n-3 LC-PUFA levels on serum TG concentrations was observed. After stratification on the n-3 LC-PUFA median values, the association between rs1260326 and TG concentration was significant only in the group with high n-3 LC-PUFA levels. In conclusion, this is the first evidence that n-3 LC-PUFAs may modulate the impact of the GCKR rs1260326 polymorphism on TG concentrations in adolescents. Several molecular mechanisms, in link with glucose uptake, could explain these findings.     

Associations between a Polymorphism in the Pleiotropic GCKR and Age-Related Phenotypes: The HALCyon Programme

Background

The glucokinase regulatory protein encoded by GCKR plays an important role in glucose metabolism and a single nucleotide polymorphism (SNP) rs1260326 (P446L) in the gene has been associated with several age-related biomarkers, including triglycerides, glucose, insulin and apolipoproteins. However, associations between SNPs in the gene and other ageing phenotypes such as cognitive and physical capability have not been reported.

Methods

As part of the Healthy Ageing across the Life Course (HALCyon) collaborative research programme, men and women from five UK cohorts aged between 44 and 90+ years were genotyped for rs1260326. Meta-analysis was used to pool within-study genotypic associations between the SNP and several age-related phenotypes, including body mass index (BMI), blood lipid levels, lung function, and cognitive and physical capability.

Results

We confirm the associations between the minor allele of the SNP and higher triglycerides and lower glucose levels. We also observed a triglyceride-independent association between the minor allele and lower BMI (pooled beta on z-score = −0.04, p-value = 0.0001, n = 16,251). Furthermore, there was some evidence for gene-environment interactions, including physical activity attenuating the effects on triglycerides. However, no associations were observed with measures of cognitive and physical capability.

Conclusion

Findings from middle-aged to older adults confirm associations between rs1260326 GCKR and triglycerides and glucose, suggest possible gene-environment interactions, but do not provide evidence that its relevance extends to cognitive and physical capability.     

Regio-distribution of stearic acid is not conserved in chylomicrons after ingestion of randomised, stearic acid-rich fat in a single meal

Stearic acid from conventional food is well absorbed, but the fate of synthetic randomized stearic acid in fat absorption and subsequent metabolism is unclear. In this study, we examined the postprandial triglyceridemia following an ingestion of randomized stearic acid-rich fat. Following a 12-h fast, nine healthy young males ate a hamburger meal with 16.7 g of stearic acid (30% in triacylglycerol (TAG) sn-2 position, fully randomized). Postprandial blood samples were collected for 450 min, and the stearic acid content in chylomicron (CM, Svedberg flotation rate >400) TAG and the proportion of stearic acid in the sn-2 position were measured by tandem mass spectrometry at peak (180 min) and late (360 min) triglyceridemia. Of all stearic acid in CM TAG, 23% and 22% were in the sn-2 position at peak and late triglyceridemia (P<.004 and P<.001, respectively). This suggests a 68% and 62% conservation of sn-2 stearic acid, respectively. Peak postprandial TAG concentration and incremental area under the TAG curve showed a higher correlation with the fasting CM TAG (r=0.88, P<.01 and r=0.72, P<.05, respectively) than with total fasting plasma TAG (r=0.73, P<.05 and r=0.24, nonsignificant, respectively). In an earlier study, we showed that the absorption efficiency of the stearic acid of the meal was normal, with only marginal amounts of mainly sn-1,3 stearic acid found in the feces. In conclusion, we showed that sn-2 stearic acid is underrepresented in the postprandial CM TAG following an ingestion of fully randomized fat.     

Causal Relationship between Adiponectin and Metabolic Traits: A Mendelian Randomization Study in a Multiethnic Population

Background

Adiponectin, a secretagogue exclusively produced by adipocytes, has been associated with metabolic features, but its role in the development of the metabolic syndrome remains unclear.

Objectives

We investigated the association between serum adiponectin level and metabolic traits, using both observational and genetic epidemiologic approaches in a multiethnic population assembled in Canada.

Methods

Clinical data and serum adiponectin level were collected in 1,157 participants of the SHARE/SHARE-AP studies. Participants were genotyped for the functional rs266729 and rs1260326 SNPs in ADIPOQ and GCKR genes.

Results

Adiponectin level was positively associated with HDL cholesterol and negatively associated with body mass index, waist-to-hip ratio, triglycerides, fasting glucose, fasting insulin, systolic and diastolic pressure (all P<0.002). The rs266729 minor G allele was associated with lower adiponectin and higher HOMA-IR (P = 0.004 and 0.003, respectively). The association between rs266729 SNP and HOMA-IR was no longer significant after adjustment for adiponectin concentration (P = 0.10). The rs266729 SNP was associated with HOMA-IR to an extent that exceeded its effect on adiponectin level (0.15 SD 95% C.I. [0.06, 0.24], P<0.001). There was no significant interaction between rs266729 SNP and ethnicity on adiponectin or HOMA-IR. In contrast, the SNP rs1260326 in GCKR was associated with HOMA-IR (P<0.001), but not with adiponectin level (P = 0.67).

Conclusion

The association of the functional promoter polymorphism rs266729 with lower serum adiponectin and increased insulin resistance in diverse ethnic groups may suggest a causal relationship between adiponectin level and insulin resistance.     

Common functional variants of APOA5 and GCKR accumulate gradually in association with triglyceride increase in metabolic syndrome patients

The common functional variants of the apolipoprotein A5 (APOA5) and the glucokinase regulatory protein genes (GCKR) have been shown to associate with increased fasting triglyceride (TG) levels. Albeit the basic association has been extensively investigated in several populations of different origin, less is known about quantitative traits of them. In our study accumulation rates of four APOA5 (T-1131, IVS3 + G476A, T1259C and C56G) and two GCKR (C1337T and rs780094) functional SNPs were analyzed in patients stratified into four TG quartile groups. Randomly selected 325 metabolic syndrome patients were separated into four quartile (q) groups based on the TG levels as follows q1: TG <1.38 mmol/l; q2: 1.38–1.93 mmol/l; q3: 1.94–2.83 mmol/l; and q4: TG >2.83 mmol/l. We observed significant stepwise increase of prevalence rates of minor allele frequencies in the four plasma TG quartiles for three APOA5 SNPs: −1131C (q1: 4.94%; q2: 8.64%; q3: 11.6%; q4: 12.3%), IVS3 + 476A (q1: 4.32%; q2: 7.4%; q3: 10.36%; q4: 11.1%), and 1259C (q1: 4.94%; q2: 7.41%; q3: 10.4%; q4: 11.7%). The haplotype analysis revealed, that the frequency of APOA5*2 haplotype gradually increased in q2, q3 and q4 (q1: 9.87%; q2: 14.8%; q3: 18.3%; q4: 21%). The distribution of the homozygotes of the two analyzed GCKR variants resembled to the APOA5 pattern. Contrary to the hypothetically predictable linear association coming from the current knowledge about the APOA5 and GCKR functions, the findings presented here revealed a unique, TG raise dependent gradual accumulation of the functional variants of in MS patients. Thus, the findings of the current study serve indirect evidence for the existence of rare APOA5 and GCKR haplotypes in metabolic syndrome patients with higher TG levels, which contribute to the complex lipid metabolism alteration in this disease.     

Association of Genetic Variants with Isolated Fasting Hyperglycaemia and Isolated Postprandial Hyperglycaemia in a Han Chinese Population

Background

Though multiple single nucleotide polymorphisms (SNPs) associated with type 2 diabetes have been identified, the genetic bases of isolated fasting hyperglycaemia (IFH) and isolated postprandial hyperglycaemia (IPH) were still unclear. In present study, we aimed to investigate the association of genome-wide association study-validated genetic variants and IFH or IPH in Han Chinese.

Methods/Principal Findings

We genotyped 27 validated SNPs in 6,663 unrelated individuals comprising 341 IFH, 865 IPH, 1,203 combined fasting hyperglycaemia and postprandial hyperglycaemia, and 4,254 normal glycaemic subjects of Han ancestry. The distributions of genotype frequencies of FTO, CDKAL1 and GCKR were significant different between individuals with IFH and those with IPH (SNP(p_trend): rs8050136(0.0024), rs9939609(0.0049), rs7756992(0.0122), rs780094(0.0037)). Risk allele of FTO specifically increased the risk of IFH (rs8050136: OR 1.403 [95% CI 1.125–1.750], p = 0.0027; rs9939609: 1.398 [1.120–1.744], p = 0.0030). G allele of CDKAL1 specifically increased the risk of IPH (1.217 [1.092–1.355], p = 0.0004). G allele of GCKR increased the risk of IFH (1.167 [0.999–1.362], p = 0.0513), but decreased the risk of IPH (0.891 [0.801–0.991], p = 0.0331). In addition, TCF7L2 and KCNQ1 increased the risk of both IFH and IPH. When combined, each additional risk allele associated with IFH increased the risk for IFH by 1.246-fold (p<0.0001), while each additional risk allele associated with IPH increased the risk for IPH by 1.190-fold (p<0.0001).

Conclusion/Significance

Our results indicate that genotype distributions of variants from FTO, GCKR, CDKAL1 were different between IPH and IFH in Han Chinese. Variants of genes modulating insulin sensitivity (FTO, GCKR) contributed to the risk of IFH, while variants of genes related to beta cell function (CDKAL1) increase the risk of IPH.     

A common variant in the adiponectin gene and polycystic ovary syndrome risk

In this study, we explored whether polymorphisms in insulin receptor (INSR), adiponectin (ADIPOQ), parathyroid hormone (PTH), and vitamin D receptor (VDR) genes are associated with polycystic ovary syndrome (PCOS). A total of 362 subjects, including 181 women with PCOS and 181 controls were enrolled in this case-control study. Two SNPs (rs2059806 and rs1799817) in the INSR gene, two SNPs (rs2241766 and rs1501299) in the ADIPOQ gene, one SNP (rs6256) in the PTH gene, and one SNP (rs757343) in the VDR gene were analyzed using PCR-RFLP method. We observed no significant difference in genotype and allele frequencies between the women with PCOS and controls for the rs2059806, rs1799817, rs1501299, rs6256, and rs757343 polymorphisms either before or after adjustment for confounding factors including age and BMI. However, the ADIPOQ rs2241766 “TT” genotype compared with “TG and GG” genotypes was associated with a 1.93-fold increased risk for PCOS (P = 0.006, OR = 1.93, 95% CI = 1.20–3.11), and the differences remained significant after adjustment for age and BMI (P = 0.039, OR = 1.72, 95% CI = 1.03–2.86). Furthermore, the ADIPOQ rs2241766 “T” allele was significantly overrepresented in women with PCOS than controls (P = 0.006; OR = 1.80, 95% CI = 1.18–2.70), and the difference remained significant after Bonferroni correction. Our findings suggest that the ADIPOQ rs2241766 “TT” genotype is a marker of increased PCOS susceptibility. This study also indicates for the first time that there are no significant association between INSR rs2059806, PTH rs6256, and VDR rs757343 gene polymorphisms and PCOS risk. However, these data remain to be confirmed in larger studies and in other populations.     

Genetic variation in the GCKR gene is associated with non-alcoholic fatty liver disease in Chinese people

Recent genome-wide association studies reported that GCKR rs780094 polymorphism is associated with elevated fasting serum triglyceride levels and elevated levels of C-reactive protein (CRP). There are a ample of data on the association between circulating triglyceride, CRP concentrations and risk of non-alcoholic fatty liver (NAFLD). To determine whether the GCKR rs780094 polymorphism contributes to the development of non-alcoholic fatty liver, a case?Ccontrol study was performed in 903 Chinese subjects. Among study population, 436 patients with B-mode ultrasound-proven NAFLD (318 with steatosis hepatis I°, 90 with steatosis hepatis II° and 28 with steatosis hepatis III°) and 467 controls were genotyped by using TaqMan allelic discrimination assays. We confirmed the association of GCKR rs780094 with NAFLD in Chinese people (OR = 1.607, 95% CI 1.139?C2.271, P _[dom] = 7.2 × 10^?3). In this study, polymorphism in GCKR rs780094 was not significantly associated with the degree of fatty infiltration of the liver. In addition, the T-allele of GCKR rs780094 was significantly associated with increasing fasting triglyceride (P _[add] = 3.8 × 10^?4) and CRP (P _[add] = 2.9 × 10^?4) concentrations after adjusting for age, gender, and BMI. The association with NAFLD remained significant after adjustment for triglyceride, while adjustment for CRP abolished the association. Genetic variation in GCKR gene rs780094 polymorphism contributes to the risk of NAFLD in Chinese people. The effect of genotype on NAFLD is probably mediated through chronic low-grade systemic inflammation rather than through dislipidemia.     

Associations between matrilin-1 gene polymorphisms and adolescent idiopathic scoliosis curve patterns in a Korean population

Adolescent idiopathic scoliosis (AIS) is a complex disorder with an unclear etiology and pathogenesis. In previous studies, genome-wide linkage and genetic association analyses have been carried out to find genetic factors linked with AIS. In this study, we examined whether the susceptibility to AIS is associated with MATN1 gene polymorphisms in a Korean population, which included 166 individuals with AIS and 126 controls. We found that there were no statistically significant associations between any of the MATN1-linked allele or genotype frequencies between AIS and controls. However, statistically significant associations were found at single nucleotide polymorphism (SNP) rs1065755 when comparing the curve patterns of AIS with the controls. The A allele of SNP rs1065755 was associated with a higher risk of AIS than the allele G in the genotype–phenotype (curve pattern) analysis (P = 0.029). In addition, the frequency of the A allele of SNP rs1065755 in AIS with double major curves was higher than in controls (P = 0.021, ORs = 2.56 within 95% CI = 1.12–5.83). Additionally, among the predicted common haplotypes, the frequency of the haplotype GATT (31.3%) in AIS with double major curves was higher than in controls (15.2%) (P = 0.024, ORs = 2.54 within 95% CI = 1.11–5.84). We conclude that the A allele of SNP rs1065755 in the MATN1 gene is associated with AIS.     

Effects of genetic variants in ADCY5, GIPR, GCKR and VPS13C on early impairment of glucose and insulin metabolism in children

Objective

Recent genome-wide association studies identified novel candidate genes for fasting and 2 h blood glucose and insulin levels in adults. We investigated the role of four of these loci (ADCY5, GIPR, GCKR and VPS13C) in early impairment of glucose and insulin metabolism in children.

Research Design and Methods

We genotyped four variants (rs2877716; rs1260326; rs10423928; rs17271305) in 638 Caucasian children with detailed metabolic testing including an oGTT and assessed associations with measures of glucose and insulin metabolism (including fasting blood glucose, insulin levels and insulin sensitivity/secretion indices) by linear regression analyses adjusted for age, sex, BMI-SDS and pubertal stage.

Results

The major allele (C) of rs2877716 (ADCY5) was nominally associated with decreased fasting plasma insulin (P = 0.008), peak insulin (P = 0.009) and increased QUICKI (P = 0.016) and Matsuda insulin sensitivity index (P = 0.013). rs17271305 (VPS13C) was nominally associated with 2 h blood glucose (P = 0.009), but not with any of the insulin or insulin sensitivity parameters. We found no association of the GIPR and GCKR variants with parameters of glucose and insulin metabolism. None of the variants correlated with anthropometric traits such as height, WHR or BMI-SDS, which excluded potential underlying associations with obesity.

Conclusions

Our data on obese children indicate effects of genetic variation within ADCY5 in early impairment of insulin metabolism and VPS13C in early impairment of blood glucose homeostasis.     

SNP rs2243828 in MPO associated with myeloperoxidase level and atrial fibrillation risk in Chinese Han population

Previous studies shown that myeloperoxidase (MPO) level is higher in patients with atrial fibrillation (AF); however, no genetic evidence between MPO and AF risk in human population was observed. Therefore, the present study was aimed to investigate the association between rs2243828, a variant in promoter region of MPO and the risk of AF in Chinese GeneID population. The results demonstrated that the minor G allele of rs2243828 showed a significant association with AF in two independent population (GeneID‐north population with 694 AF cases and 710 controls, adjusted P_‐adj = 6.25 × 10^?3 with an odds ratio was 0.77, GeneID‐central population with 1106 cases and 1501 controls, P_‐adj = 9.88 × 10^?5 with an odds ratio was 0.75). The results also showed G allele was significantly associated with lower plasma concentration of myeloperoxidase in general population. We also observed a significant difference of odds ratio between subgroups of hypertension and non‐hypertension. Therefore, our findings identified variant in MPO associated with risk of AF and it may give strong evidence to link the inflammation with the incidence of AF.     

<Emphasis Type="Italic">MLXIPL</Emphasis> variant in individuals with low and high triglyceridemia in white population in Central Europe

We tested the hypothesis that the MLXIPL rs3812316 variant predicts plasma triglyceride (TG) levels. We compared three groups of adult individuals: 162 persons with TG > 10 mmol/L, 266 persons with TG < 0.65 mmol/L, and 2,043 population-based controls (range of TG concentrations 0.7–8.7 mmol/L). We found a small difference in the frequency of the Gln allele carriers between population controls (20.4%) and persons with low TG (26.3%, P = 0.033). We found no difference between individuals with high TG and population controls, and there was no association between the MLXIPL variant and plasma TG levels among the population controls.     

Association of type 2 diabetes susceptibility genes (TCF7L2, SLC30A8, PCSK1 and PCSK2) and proinsulin conversion in a Chinese population

TCF7L2 and SLC30A8 have been found to be associated with type 2 diabetes mellitus (T2DM) as well as with impaired proinsulin processing recently, enzymes encoded by PCSK1 and PCSK2 are reported to play an important role in the process of proinsulin conversion. To investigate whether the single nucleotide polymorphisms (SNPs) of TCF7L2, SLC30A8, PCSK1 and PCSK2 were associated with T2DM as well as with proinsulin conversion in a Han Chinese population from Chongqing. A case–control study was performed in Han Chinese subjects with normal control (n = 152) and T2DM (n = 227), we genotyped rs7903146 and rs11196218 at TCF7L2, rs13266634 at SLC30A8, rs3811951 at PCSK1 and rs2021785 at PCSK2. Plasma levels of proinsulin were measured with an Enzyme Linked Immunosorbent Assay (ELISA). Genotype distribution and associations with T2DM and fasting levels of proinsulin and proinsulin/insulin ratios were analyzed. We confirmed the association of risk allele of rs2021785 at PCSK2 with type 2 diabetes also existed in Han Chinese population [OR = 1.4489 with 95% CI (1.0285, 2.0412), P = 0.0335]. Rs13266634 at SLC30A8 had a tendency to be associated with fasting plasma levels of proinsulin (P = 0.0639 in additive model). We did not find the significant association between other SNPs and T2DM or fasting levels of proinsulin or proinsulin/insulin ratios. Our results provide evidence that the association of PCSK2 and T2DM was also existed in Han Chinese population in Chongqing. We were underpowered to detect the association between other SNPs and T2DM or proinsulin conversion.     

Replication study of novel risk variants in six genes with type 2 diabetes and related quantitative traits in the Han Chinese lean individuals

To replicating the associations of type 2 diabetes (T2D) and six novel reported variants in Han Chinese lean individuals of first episode T2D, a total of six high risk single nucleotide polymorphisms (SNPs) from the BCL11A, DUSP9, IRS1, CENTD2, ADRA2A, and CDKAL1 genes were examined. Candidate six SNPs were genotyped in 761 T2D patients and 433 control subjects, and associations between the six SNPs and Body Mass Index (BMI), Fasting Plasma Glucose (FPG) and Two Hours Oral Glucose Tolerance Test (2hOGTT) were also investigated. CDKAL1 provided the strongest evidence for replication, where rs7754840 was associated with T2D (odds ratio = 1.54, per copy of the risk C allele, P = 8.10 × 10⁻⁷). SNP rs5945326 at DUSP9 showed modest significance (odds ratio = 0.81, per copy of the protective G allele, P = 0.02). After adjusting the confounders of age, gender and BMI, the above results remain significant for both rs7754840 (P < 1.0 × 10⁻⁴) and rs5945326 (P = 0.043) respectively. After correcting for multiple testing, however, only the association between T2D and rs7754840 at CDKAL1 (P < 1×10⁻⁴) remains significant. In addition, the risk C allele of CDKAL1 rs7754840 was significantly associated with increased FPG levels (P = 3.8 × 10⁻⁴). The association between genetic variant in CDKAL1 gene was detected in the Han Chinese lean individuals. The correlation between rs7754840-C allele and increased FPG levels is consistent with the potential function of CDKAL1 gene in pancreatic islets.     

Glucokinase regulatory protein genetic variant interacts with omega-3 PUFA to influence insulin resistance and inflammation in metabolic syndrome

Glucokinase Regulatory Protein (GCKR) plays a central role regulating both hepatic triglyceride and glucose metabolism. Fatty acids are key metabolic regulators, which interact with genetic factors and influence glucose metabolism and other metabolic traits. Omega-3 polyunsaturated fatty acids (n-3 PUFA) have been of considerable interest, due to their potential to reduce metabolic syndrome (MetS) risk.

Objective

To examine whether genetic variability at the GCKR gene locus was associated with the degree of insulin resistance, plasma concentrations of C-reactive protein (CRP) and n-3 PUFA in MetS subjects.

Design

Homeostasis model assessment of insulin resistance (HOMA-IR), HOMA-B, plasma concentrations of C-peptide, CRP, fatty acid composition and the GCKR rs1260326-P446L polymorphism, were determined in a cross-sectional analysis of 379 subjects with MetS participating in the LIPGENE dietary cohort.

Results

Among subjects with n-3 PUFA levels below the population median, carriers of the common C/C genotype had higher plasma concentrations of fasting insulin (P = 0.019), C-peptide (P = 0.004), HOMA-IR (P = 0.008) and CRP (P = 0.032) as compared with subjects carrying the minor T-allele (Leu446). In contrast, homozygous C/C carriers with n-3 PUFA levels above the median showed lower plasma concentrations of fasting insulin, peptide C, HOMA-IR and CRP, as compared with individuals with the T-allele.

Conclusions

We have demonstrated a significant interaction between the GCKR rs1260326-P446L polymorphism and plasma n-3 PUFA levels modulating insulin resistance and inflammatory markers in MetS subjects. Further studies are needed to confirm this gene-diet interaction in the general population and whether targeted dietary recommendations can prevent MetS in genetically susceptible individuals.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00429195","term_id":"NCT00429195"}}NCT00429195     

Effects of a genetic variant rs13266634 in the zinc transporter 8 gene (SLC30A8) on insulin and lipid levels before and after a high-fat mixed macronutrient tolerance test in U.S. adults

BackgroundThe common C-allele of rs13266634 (c.973C>T or p.Arg325Trp) in SLC30A8 (ZNT8) is associated with increased risk of type 2 diabetes. While previous studies have examined the correlation of the variant with insulin and glucose metabolism, the effects of this variant on insulin and lipid responses after a lipid challenge in humans remain elusive. The goal of this study was to determine whether the C-allele had an impact on an individual’s risk to metabolic syndromes in U.S. adults.MethodWe studied the genotypes of rs13266634 in 349 individuals aged between 18 and 65 y with BMI ranging from 18.5 to 45 kg/m². The subjects were evaluated for insulin, glucose, HbA1c, ghrelin, and lipid profiles before and after a high-fat mixed macronutrient tolerance test (MMTT).ResultsWe found that the effects of variants rs13266634 on glucose and lipid metabolism were sex-dimorphic, greater impact on males than on females. Insulin incremental area under the curve (AUC) after MMTT was significantly decreased in men with the CC genotype (p < 0.05). Men with the CC genotype also had the lowest fasting non-esterified fatty acid (NEFA) concentrations. On the other hand, the TT genotype was associated with a slower triglyceride removal from the circulation in men after MMTT. The reduced triglyceride removal was also observed in subjects with BMI ≥ 30 carrying either the heterozygous or homozygous T-allele. Nevertheless, the SNP had little effect on fasting or postprandial blood glucose and cholesterol concentrations.ConclusionWe conclude that the CC genotype negatively affects insulin response after MMTT while the T-allele may negatively influence lipolysis during fasting and postprandial blood triglyceride removal in men and obese subjects, a novel finding in this study.     

Acute effects of Amomum villosum Lour. fruit extract on postprandial glycemia and insulin secretion: A single-blind,placebo-controlled,crossover study in healthy subjects

BackgroundAmomum villosum Lour., (Zingiberaceae) an herbaceous plant in the ginger family, has been used to treat various diseases. In a single-blind, randomized, crossover study, we assessed the postprandial blood insulin and blood glucose responses in healthy subjects (n = 40) after the Amomum villosum water extract (AVE) (5 g/person) or a placebo (5 g/person) consumption.MethodsDuring each treatment course, the healthy subject consumed a regular late afternoon meal, followed by fasting for 12 h, and arrived at the clinical study center the next morning. Blood insulin and blood glucose levels were assessed at 0, 30, 60, 90, and 120 min after AVE consumption. Between each treatment, the subjects accomplished one week of a washout period.ResultsThe AVE intake demonstrated a significant (67.26%) decline in postprandial blood glucose AUC_{0–120 min} (incremental area under the curve from 0 to 120 min) versus the placebo (P = 0.011). Furthermore, AVE reduced postprandial blood insulin AUC_{0–120 min} by 59.95% compared to the placebo group (P < 0.003), supporting the blood glucose results.ConclusionThis study revealed that AVE consumption significantly reduced postprandial insulin and glucose levels in healthy individuals, due in part to inhibition of α-glucosidase, and glucose transport.     

SNPs in SNCA,MCCC1, DLG2, GBF1 and MBNL2 are associated with Parkinson's disease in southern Chinese population

Numerous single nucleotide polymorphisms (SNPs), which have been identified as susceptibility factors for Parkinson's disease (PD) as per genome‐wide association studies, have not been fully characterized for PD patients in China. This study aimed to replicate the relationship between 12 novel SNPs of 12 genes and PD risk in southern Chinese population. Twelve SNPs of 12 genes were detected in 231 PD patients and 249 controls, using the SNaPshot technique. Meta‐analysis was used to assess heterogeneity of effect sizes between this study and published data. The impact of SNPs on gene expression was investigated by analysing the SNP‐gene association in the expression quantitative trait loci (eQTL) data sets. rs8180209 of SNCA (allele model: P = .047, OR = 0.77; additive model: P = .047, OR = 0.77), rs2270968 of MCCC1 (dominant model: P = .024, OR = 1.52), rs7479949 of DLG2 (recessive model; P = .019, OR = 1.52), rs10748818 of GBF1 (additive model: P < .001, OR = 0.37), and rs4771268 of MBNL2 (recessive model: P = .003, OR = 0.48) were replicated to be significantly associated with the increased risk of PD. Noteworthy, a meta‐analysis of previous studies suggested rs8180209, rs2270968, rs7479949 and rs4771268 were in line with those of our cohort. Our study replicated five novel functional SNPs in SNCA, MCCC1, DLG2, GBF1 and MBNL2 could be associated with increased risk of PD in southern Chinese population.     

Association of IFN‐γ polymorphisms with ankylosing spondylitis risk

The case‐control study was designed to investigate the genetic effects of interferon‐gamma (IFN‐γ) rs2069727 and rs1861494 polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese Han population. Blood samples were collected from 108 AS patients and 110 healthy controls. IFN‐γ polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). Hardy‐Weinberg equilibrium (HWE) test was performed in control group. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using chi‐square test to evaluate the association between AS susceptibility and IFN‐γ polymorphisms, and the results were adjusted by logistic regressive analysis. The frequency of rs2069727 CC genotype was much higher in cases than that in controls, suggested its significant association with increased AS risk (adjusted OR = 5.899, 95% CI = 1.563‐22.261; P = .009). In addition, C allele also showed close association with increased risk of AS (adjusted OR = 2.052, 95% CI = 1.286‐1.704, P  = 0 .003). While the genotype and allele frequencies of IFN‐γ rs1861494 polymorphism were not significantly different between patients and controls (P  > 0.05 for all), IFN‐γ rs2069727 polymorphism is significantly associated with increased AS risk in a Chinese Han Population.