Genetic Factors in Type 2 Diabetes: The End of the Beginning?

Asymmetric synthesis of the fully functionalized six-membered A-ring of siphonol A

A synthetic study toward the construction of the fully functionalized six-membered A-ring of siphonol A is described. The salient features include the introduction of a six-membered ring system through a HWE reaction, the construction of a stereocenter at C5 via a hetero-Diels-Alder reaction, and the installation of the fully functionalized six-membered A-ring of siphonol A through photolytic decarboxylation.

Partners in diabetes epidemic: A global perspective

There is a recent increase in the worldwide prevalence of both obesity and diabetes. In this review we assessed insulin signaling, genetics, environment, lipid metabolism dysfunction and mitochondria as the major determinants in diabetes and to identify the potential mechanism of gut microbiota in diabetes diseases. We searched relevant articles, which have key information from laboratory experiments, epidemiological evidence, clinical trials, experimental models, meta-analysis and review articles, in PubMed, MEDLINE, EMBASE, Google scholars and Cochrane Controlled Trial Database. We selected 144 full-length articles that met our inclusion and exclusion criteria for complete assessment. We have briefly discussed these associations, challenges, and the need for further research to manage and treat diabetes more efficiently. Diabetes involves the complex network of physiological dysfunction that can be attributed to insulin signaling, genetics, environment, obesity, mitochondria and stress. In recent years, there are intriguing findings regarding gut microbiome as the important regulator of diabetes. Valid approaches are necessary for speeding medical advances but we should find a solution sooner given the burden of the metabolic disorder - What we need is a collaborative venture that may involve laboratories both in academia and industries for the scientific progress and its application for the diabetes control.

Leu72Met Polymorphism in Ghrelin Gene: A Potential Risk Factor for Hypertension in Type 2 Diabetes Patients

OBJECTIVE

Ghrelin (GHRL) is known to be engaged in metabolic and cardiovascular processes. There is evidence suggesting its involvement in the regulation of blood pressure and hypertension. The purpose of this preliminary case-control study was to determine the involvement of the Leu72Met (rs696217) polymorphism in the GHRL gene in type 2 diabetes (T2DM).

METHODS

The Leu72Met polymorphism was genotyped in 820 individuals with T2DM and 400 healthy subjects by the PCR-RFLP technique. The polymorphism distribution was first compared in those withT2DM and controls, then in subgroups of participants representing different clinical phenotypes.

RESULTS

No significant association was identified between Leu72Met and T2DM. The distribution of polymorphism was analyzed in subgroups of individuals with different clinical phenotypes (hypertension, diabetic nephropathy, obesity). In this analysis, rs696217 was associated with hypertension. The presence of T allele was associated with higher risk of hypertension (OR = 2.50, 95% CI 1.68-3.73, p < 0.001). When adjusted for age, gender and BMI, the association was still significant (OR = 2.62, 95% CI 1.83-3.96, p < 0.001). A post hoc power calculations based on a minor allele frequency revealed the power of 97% for comparison between HY+ and HY- subgroups.

CONCLUSION

This is the first study demonstrating that the ghrelin Leu72Met SNP is associated with hypertension in Caucasians with T2DM. If confirmed in larger studies in different populations, it may be a novel potential risk factor for hypertension in individuals withT2DM.

Higher Waist Hip Ratio Genetic Risk Score Is Associated with Reduced Weight Loss in Patients with Severe Obesity Completing a Meal Replacement Programme

Background: A better understanding of the influence of genetic factors on the response to lifestyle interventions in people with obesity may allow the development of more personalised, effective and efficient therapeutic strategies. We sought to determine the influence of six obesity-related genetic risk scores on the magnitude of weight lost by patients with severe obesity who completed a dietary intervention. Methods: In this single-centre prospective cohort study, participants with severe and complicated obesity who completed a 24-week, milk-based meal replacement programme were genotyped to detect the frequency of common risk alleles for obesity and type 2 diabetes-related traits. Genetic risk scores (GRS) for six of these traits were derived. Participants with a potentially deleterious monogenic gene variant were excluded from the analysis. Results: In 93 patients completing the programme who were not carrying a known obesity-related gene mutation, 35.5% had diabetes, 53.8% were female, mean age was 51.4 ± 11 years, mean body mass index was 51.5 ± 8.7 and mean total weight loss percent at 24 weeks was 16 ± 6.3%. The waist-hip ratio (WHR) GRS was inversely associated with percentage total weight loss at 24 weeks (adjusted β for one standard deviation increase in WHR GRS -11.6 [-23.0, -0.3], p = 0.045), and patients in the lowest tertile of WHR GRS lost more weight. Conclusions: Patients with severe and complicated obesity with a genetic predisposition to central fat accumulation had less weight loss in a 24-week milk-based meal replacement programme, but there was no evidence for influence from the five other obesity-related genetic risk scores on the response to dietary restriction.

Pediatric Preventive Care in Middle-High Resource Countries-The Padova Chart for Health in Children

Importance

The Padova Chart for Health in Children (PCHC) aims to gather the evidence of healthcare promotion and protection for chidren and adolescents (i.e., aged <18 y) into a single document in order to guide families, healthcare providers and social actors on healthy choices. No more than 2% of Europeans and North Americans aged <30 y have a healthy lifestyle. This, together with metabolic and brain plasticity during childhood, creates the ideal opportunity to implement preventive strategies. Guided interventions promoting healthy lifestyle in children and families therefore have a key role in abating the unprecedented pandemic of non-communicable diseases (NCDs) in adulthood.

Observations

The PCHC is divided into four sections: nutrition, cardiovascular health, respiratory health, and mental and social health. Each section is structured in an ALICE approach (assessment, lobbying, intervention, call-for-action, evaluation): assessment of necessity, describing relevance to healthcare; lobbying to identify those who can effect the proposed interventions; interventions involving family, school and peers; a call-for-action to define priorities among the proposed interventions; and objective evaluation measures that can be applied on a population basis.

Conclusions and Relevance

Interventions promoting health in childhood require joint action from multiple institutional, local and family representatives, with the shared goal of promoting health across the entire age group. These lifestyle interventions have the potential to change the lifetime risk trajectory for NCDs.

Clinical Study on the Relationship between the SNP rs8192675 (C/C) Site of SLC2A2 Gene and the Hypoglycemic Effect of Metformin in Type 2 Diabetes

This study investigates the correlation between the gene polymorphism of rs8192675 (C/C) locus of SLC2A2 in patients with type 2 diabetes (T2DM) and the efficacy of metformin. For this purpose, we have selected 110 T2DM patients (T2DM group) and 110 healthy people (control group) who were treated in our hospital from January 2019 to January 2020 as the research subjects. PCR-restriction fragment length polymorphism (PCR-RFLP) method detects the distribution frequency of gene polymorphism. The patients in the T2DM group were treated with metformin and followed up for 90 days to analyze the relationship between the efficacy of metformin and the SLC2A2 gene polymorphism. The genotypes of SLC2A2 rs8192675 in the control group and in the T2DM group conformed to the Hardy–Weinberg equilibrium law. Compared with the control group, the CT type and the CC type at rs8192675 in the T2DM group were significantly higher (P < 0.05). For rs8192675, there was no significant difference in TT, CT, CC FPG, 2hPBG, and HbA1c levels before treatment (P > 0.05); after metformin treatment, the reduction in FPG, 2hPBG, and HbA1c in CC patients was lower than that of TT and CT patients (P < 0.05). SLC2A2 gene polymorphism site rs8192675 CC type T2DM patients are sensitive to metformin and have a better hypoglycemic effect.

Mitochondrial haplogroups have a better correlation to insulin requirement than nuclear genetic variants for type 2 diabetes mellitus in Taiwanese individuals

AIMS/INTRODUCTION

Identifying diabetes-susceptible genetic variants will help to provide personalized therapy for the management of type 2 diabetes. Previous studies have reported a genetic risk score (GRS), computed by the sum of nuclear DNA (nDNA) risk alleles, that may predict the future requirement for insulin therapy. Although mitochondrial dysfunction has a close association with insulin resistance (IR), there are few studies investigating whether genetic variants of mitochondrial DNA (mtDNA) will affect the clinical characteristics of type 2 diabetes.

MATERIALS AND METHODS

Mitochondrial haplogroups were determined using mtDNA whole genome next generation sequencing and 13 single nucleotide polymorphisms (SNPs) in nDNA susceptibility loci of 13 genes in 604 Taiwanese subjects with type 2 diabetes. A GRS of nDNA was computed by summation of the number of risk alleles. The correlation between the mtDNA haplogroup and the clinical characteristics of type 2 diabetes was assessed by logistic regression analysis. The results were compared with the GRS subgroups for the risk of insulin requirement.

RESULTS

Mitochondrial haplogroups modulate the clinical characteristics of type 2 diabetes, in which patients harboring haplogroup D4, compared with those harboring non-D4 haplotypes, were less prone to require insulin treatment, after adjusting for age, gender, and diabetes duration. However, there was no association between insulin requirement and GRS calculated from nuclear genetic variants.

CONCLUSIONS

Mitochondrial haplogroups, but not nuclear genetic variants, have a better association with the insulin requirement. The results highlight the role of mitochondria in the management of common metabolic diseases.

Renalase gene Glu37Asp polymorphism affects susceptibility to diabetic retinopathy in type 2 diabetes mellitus

AIMS

Renalase (RNLS) is an enzyme with monoamine oxidase activity that metabolizes circulating catecholamines. The RNLS gene Asp37Glu missense polymorphism (rs2296545) has been associated with hypertension, cardiac hypertrophy and dysfunction, and stroke. The purpose of our study was to investigate the potential involvement of this polymorphism in the microvascular complications of type 2 diabetes (T2DM).

METHODS

In this case-control study, the polymorphism was genotyped in 860 patients with T2DM and 400 healthy controls. The genotype and allele distribution was compared in subgroups of patients: with diabetic nephropathy (DN+) (n = 405) versus DN- (independently of the presence of DR) and, similarly, patients with diabetic retinopathy (DR+) (n = 328) versus DR- (independently of the presence of DN).

RESULTS

No significant association was detected between analyzed polymorphism and DN. In contrast, the retinopathy subgroup showed a significantly higher frequency of G allele (OR 1.4, 95% CI 1.16-1.72, p = 0.0005) and GG genotype (OR 1.86, 95% CI 1.26-2.75, p = 0.001) than DR- patients. The effect of RNLS Glu37Asp polymorphism on DR remained significant after adjustments for age, gender, BMI, and duration of T2DM (p = 0.005).

CONCLUSIONS

This is the first study to investigate RNLS gene polymorphism in microvascular complications of T2DM. The results suggest that RNLS rs2296545 SNP might be considered a risk factor for diabetic retinopathy in T2DM patients. This can provide new insight into the role of renalase gene in the pathophysiology of microvascular complications of diabetes.

The relationship between ambient temperature and fasting plasma glucose, temperature-adjusted type 2 diabetes prevalence and control rate: a series of cross-sectional studies in Guangdong Province, China

Background

There existed evidence that type 2 diabetes mellitus (T2DM) prevalence and control rate have seasonal variation. Our study aimed to examine the ambient temperature and fasting plasma glucose (FPG) association and estimate temperature-adjusted T2DM prevalence and control rate.

Methods

Four cross-sectional health surveys with 26,350 respondents were conducted in Guangdong Province from 2007 to 2015. Multistage cluster sampling was used to recruit study participants. The data of demographic characteristics, lifestyle factors, diet and use of hypoglycemic medicine, height, weight, FPG and meteorological information were collected. And an inverse distance-weighted method was employed to estimate daily temperature exposures at the individual’ s residential district/county. Base on World Health Organization 2006 criteria, participants were divided into normal fasting glucose (NFG) participants (n = 23,877), known T2DM patients (n = 916) and newly detected T2DM patients (n = 1557). Generalized additive mixed model was employed to evaluate the nonlinear associations between temperature and FPG among different T2DM subgroups. The T2DM prevalence and control rate were estimated based on temperature-FPG association.

Results

The curves of temperature and FPG were downward parabola for total, NFG and known T2DM groups, while it was “U”-shaped for newly detected T2DM patients. When temperature decreased from 30 °C to 4 °C, the FPG significantly increased 0.24 (95%CI: 0.15, 0.33) mmol/L, 0.10 (95%CI: 0.06, 0.14) mmol/L and 1.34 (95%CI: 0.56, 2.12) mmol/L in total, NFG and known T2DM groups, respectively. Compared to 19 °C, newly detected T2DM patients’ FPGs were increased 0.73 (95%CI: 0.13, 1.30) mmol/L at 4 °C and 0.53 (0.00, 1.07) mmol/L at 30 °C. The model-estimated temperature-adjusted T2DM prevalence had a down and up trend, with 9.7% at 5 °C, 8.9% at 20 °C and 9.4% at 30 °C, respectively. At 5, 10, 15, 20, 25 and 30 °C, the model-estimated temperature-adjusted T2DM control rates were 33.2, 35.4, 38.2, 43.6, 49.1 and 55.2%.

Conclusion

Temperature was negatively associated with FPG for NFG and known T2DM subgroups, while their association was U-shape for newly detected T2DM patients. Hence, the temperature-adjusted T2DM prevalence show a dip/peak pattern and T2DM control rate display a rising trend when temperature increase. Our findings suggest temperature should be considered in T2DM clinic management and epidemiological survey.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11563-5.

Comparison of the effects of sibling and parental history of type 2 diabetes on metabolic syndrome

The aim of this study was to investigate the associations between sibling history, parental history and simultaneous sibling and parental history of diabetes, and the presence of the metabolic syndrome (MetS) and its components. Our study comprised 5000 participants from Taiwan Biobank until April, 2014. The participants were stratified into four groups according to sibling and/or parental family history (FH) of DM. MetS was defined as having 3 of the following 5 abnormalities based on the standard of the NCEP ATP III and modified criteria for Asians. The prevalence of MetS and its traits was estimated and compared among the four familial risk strata. Multivariate logistic regression analysis showed participants with sibling FH of DM [vs. no FH of DM; odds ratio (OR) 1.815; 95% confidence interval (CI) 1.293 to 2.548; p = 0.001], participants with parental FH of DM (vs. no FH of DM; OR 1.771; 95% CI 1.468 to 2.135; p < 0.001), and participants with simultaneous sibling and parental FH of DM (vs. no FH of DM; OR 2.961; 95% CI 2.108 to 4.161; p < 0.001) were significantly associated with MetS. A synergistic effect of sibling FH of DM and parental FH of DM on the association of MetS was also observed. In a nationally representative sample of Taiwan adults, a simultaneous sibling and parental history of diabetes shows a significant, independent association with MetS and its components, except for abdominal obesity. The association highlights the importance of obtaining stratified FH information in clinical practice and may help to identify individuals who should be targeted for screening and early prevention of MetS.

Association between ABCC8 Ala1369Ser Polymorphism (rs757110 T/G) and Type 2 Diabetes Risk in an Iranian Population: A Case-Control Study

OBJECTIVE

Glucose metabolism increases ATP/ADP ratio within the β-cells and causes ATP-sensitive K+ (KATP) channel closure and consequently insulin secretion. The enhanced activity of the channel may be a mechanism contributing to the reduced first-phase of insulin secretion observed in T2DM. There is no study to date in the Kurdish ethnic group regarding the relationship between SNP Ala1369Ser (rs757110 T/G) of SUR1 gene and T2DM, and additionally, the results of this association in other populations are inconsistent. Therefore, our aim in this study was to explore the possible association between SNP Ala1369Ser and type 2 diabetes in an Iranian Kurdish ethnic group.

METHODS

In this study, we checked out the frequency of alleles and genotypes of SNP Ala1369Ser in T2DM individuals (207 patients; men/women: 106/101) and non-T2DM subjects (201 controls; men/women: 97/104), and their effects on anthropometric, clinical, and biochemical parameters. Genomic DNA was extracted from the leukocytes of blood specimens using a standard method. We amplified the ABCC8 rs757110 polymorphic site (T/G) using a polymerase chain reaction (PCR) method and a designed primer pair. To perform the PCR-RFLP method, the amplicons were subjected to restriction enzymes and the resulting fragments separated by gel electrophoresis.

RESULTS

The frequency of the G-allele of Ala1369Ser polymorphism was significantly (0.01) higher in the case group than the control group (19% vs. 9%, respectively). In the dominant model (TT vs. TG+GG), there was a significant relationship between this SNP and an increased risk of T2DM (P = 0.00). T2DM patients with TG+GG genotypes had significantly higher fasting plasma insulin and HOMA-IR than those who had the TT genotype (P = 0.02 and 0.01, respectively).

CONCLUSION

Our study is the first study to investigate the association between Ala1369Ser ABCC8 genetic variation and T2DM in the Kurdish population of western Iran. The obtained results clearly show that Ala1369Ser polymorphism of ABCC8 is associated with an increased risk of T2DM in this population.

Genetic locus responsible for diabetic phenotype in the insulin hyposecretion (ihs) mouse

Diabetic animal models have made significant contributions to understanding the etiology of diabetes and to the development of new medications. Our research group recently developed a novel diabetic mouse strain, the insulin hyposecretion (ihs)mouse. The strain involves neither obesity nor insulitis but exhibits notable pancreatic β-cell dysfunction, distinguishing it from other well-characterized animal models. In ihs mice, severe impairment of insulin secretion from pancreas has been elicited by glucose or potassium chloride stimulation. To clarify the genetic basis of impaired insulin secretion, beginning with identifying the causative gene, genetic linkage analysis was performed using [(C57BL/6 × ihs) F₁ × ihs] backcross progeny. Genetic linkage analysis and quantitative trait loci analysis for blood glucose after oral glucose loading indicated that a recessively acting locus responsible for impaired glucose tolerance was mapped to a 14.9-Mb region of chromosome 18 between D18Mit233 and D18Mit235 (the ihs locus). To confirm the gene responsible for the ihs locus, a congenic strain harboring the ihs locus on the C57BL/6 genetic background was developed. Phenotypic analysis of B6.ihs-(D18Mit233-D18Mit235) mice showed significant glucose tolerance impairment and markedly lower plasma insulin levels during an oral glucose tolerance test. Whole-genome sequencing and Sanger sequencing analyses on the ihs genome detected two ihs-specific variants changing amino acids within the ihs locus; both variants in Slc25a46 and Tcerg1 were predicted to disrupt the protein function. Based on information regarding gene functions involving diabetes mellitus and insulin secretion, reverse-transcription quantitative polymerase chain reaction analysis revealed that the relative abundance of Reep2 and Sil1 transcripts from ihs islets was significantly decreased whereas that of Syt4 transcripts were significantly increased compared with those of control C57BL/6 mice. Thus, Slc25a46, Tcerg1, Syt4, Reep2 and Sil1 are potential candidate genes for the ihs locus. This will be the focus of future studies in both mice and humans.

Mitochondrial Dysfunction, Insulin Resistance, and Potential Genetic Implications

Insulin resistance (IR) is fundamental to the development of type 2 diabetes (T2D) and is present in most prediabetic (preDM) individuals. Insulin resistance has both heritable and environmental determinants centered on energy storage and metabolism. Recent insights from human genetic studies, coupled with comprehensive in vivo and ex vivo metabolic studies in humans and rodents, have highlighted the critical role of reduced mitochondrial function as a predisposing condition for ectopic lipid deposition and IR. These studies support the hypothesis that reduced mitochondrial function, particularly in insulin-responsive tissues such as skeletal muscle, white adipose tissue, and the liver, is inextricably linked to tissue and whole body IR through the effects on cellular energy balance. Here we discuss these findings as well as address potential mechanisms that serve as the nexus between mitochondrial malfunction and IR.

Associations of KCNQ1 Polymorphisms with the Risk of Type 2 Diabetes Mellitus: An Updated Meta-Analysis with Trial Sequential Analysis

BACKGROUND

Previous studies have examined the role of the KQT-like subfamily Q member1 (KCNQ1) gene polymorphisms on the risk of type 2 diabetes mellitus (T2DM), but the findings are inconclusive.

OBJECTIVE

To examine the association between the KCNQ1 gene polymorphisms and the risk of T2DM using an updated meta-analysis with an almost tripled number of studies.

METHODS

Five electronic databases, such as PubMed and Embase, were searched thoroughly for relevant studies on the associations between seven most studied KCNQ1 gene polymorphisms, including rs2237892, rs2237897, rs2237895, rs2283228, rs231362, rs151290, and rs2074196, and T2DM risk up to September 14, 2019. The summary odds ratios (ORs) with their 95% confidence intervals (CIs) were applied to assess the strength of associations in the random-effects models. We used the trial sequential analysis (TSA) to measure the robustness of the evidence.

RESULTS

49 publications including 55 case-control studies (68,378 cases and 66,673 controls) were finally enrolled. In overall analyses, generally, increased T2DM risk was detected for rs2237892, rs2237895, rs2283228, rs151290, and rs2074196, but not for rs231362 under all genetic models. The ORs and 95% CIs for allelic comparison were 1.23 (1.14-1.33) for rs2237892, 1.21 (1.16-1.27) for rs2237895, 1.27 (1.11-1.46) for rs2237897, 1.25 (1.09-1.42) for rs2283228, 1.14 (1.03-1.27) for rs151290, 1.31 (1.23-1.39) for rs2074196, and 1.16 (0.83, 1.61) for rs231362. Stratified analyses showed that associations for rs2237892, rs2237895, rs2283228, and rs151290 were more evident among Asians than Caucasians. TSA demonstrated that the evidence was sufficient for all polymorphisms in this study. The genotypes of the three SNPs (rs2237892, rs2283228, and rs231362) were significantly correlated with altered KCNQ1 gene expression.

CONCLUSION

This meta-analysis suggested that KCNQ1 gene polymorphisms (rs2237892, rs2283228, rs2237895, rs151290, and rs2074196) might be the susceptible factors for T2DM, especially among Asian population.

Association of Genetic Variants of KCNJ11 and KCNQ1 Genes with Risk of Type 2 Diabetes Mellitus (T2DM) in the Indian Population: A Case-Control Study

Type 2 diabetes mellitus (T2DM) is a polygenic metabolic disease described by hyperglycemia, which is caused by insulin resistance or reduced insulin secretion. The interaction between various genetic variants and environmental factors triggers T2DM. The aim of this study was to find risk associated with genetic variants rs5210 and rs2237895 of KCNJ11 and KCNQ1 genes, respectively, in the development of T2DM in the Indian population. A total number of 300 cases of T2DM and 100 control samples were studied to find the polymorphism in KCNJ11 and KCNQ1 through PCR-RFLP. The genotype and allele frequencies in T2DM cases were significantly different compared to the control population. KCNJ11 rs5210 and KCNQ1 rs2237895 variants were found to be significantly associated with risk of T2DM in dominant (KCNJ11: OR, 2.07; 95% CI, 1.30-3.27; p - 0.001; KCNQ1: OR, 2.33; 95% CI, 1.46-3.70; p - 0.0003) and codominant models (KCNJ11: OR, 1.76; 95% CI, 1.09-2.84; p - 0.020; KCNQ1: OR, 1.85; 95% CI, 1.16-2.95; p - 0.009). We also compared clinicopathological characteristics between cases and control and observed a significant difference in all the parameters except HDL, gender, and family history. In this study, clinicopathological data with a carrier of a variant allele of both KCNJ11 and KCNQ1 genes were also analysed, and a significant association was found between the carrier of a variant allele with gender and PPG in KCNJ11 and with triglyceride in KCNQ1. We confirm the significant association of KCNJ11 (rs5210) and KCNQ1 (rs2237895) gene polymorphism with T2DM, indicating the role of these variants in developing risk for T2DM in Indian population.

Glucose Uptake Stimulatory and PTP1B Inhibitory Activities of Pimarane Diterpenes from Orthosiphon stamineus Benth

Seven pimarane diterpenes (1–7) were isolated from Orthosiphon stamineus Benth. by assay-guided isolation. All of the isolates possessed a 2-deoxy-2-((7-nitro-2,1,3-benzoxadiazol-4-yl)amino)-d-glucose uptake effect in 3T3-L1 adipocytes at concentrations of 5 and 10 μM. Most of them showed potent inhibition against protein tyrosine phosphatase 1B with IC₅₀ values ranging from 0.33 to 9.84 μM. In the kinetic study, all inhibition types were exposed for the examined potencies, including mixed-competitive (1), non-competitives (3 and 5), competitive (6), and uncompetitive (7). The results suggested that O. stamineus and its pimarane diterpenes might exert the hypoglycemic effect via the insulin signaling pathway targeting inhibition of protein tyrosine phosphatase 1B (PTP1B) activity.

Challenges and Legal Gaps of Genetic Profiling in the Era of Big Data

Profiling of individuals based on inborn, acquired, and assigned characteristics is central for decision making in health care. In the era of omics and big smart data, it becomes urgent to differentiate between different data governance affordances for different profiling activities. Typically, diagnostic profiling is in the focus of researchers and physicians, and other types are regarded as undesired side-effects; for example, in the connection of health care insurance risk calculations. Profiling in a legal sense is addressed, for example, by the EU data protection law. It is defined in the General Data Protection Regulation as automated decision making. This term does not correspond fully with profiling in biomedical research and healthcare, and the impact on privacy has hardly ever been examined. But profiling is also an issue concerning the fundamental right of non-discrimination, whenever profiles are used in a way that has a discriminatory effect on individuals. Here, we will focus on genetic profiling, define related notions as legal and subject-matter definitions frequently differ, and discuss the ethical and legal challenges.

Light at night exacerbates metabolic dysfunction in a polygenic mouse model of type 2 diabetes mellitus

AIMS

Electric lighting is beneficial to modern society; however, it is becoming apparent that light at night (LAN) is not without biological consequences. Several studies have reported negative effects of LAN on health and behavior in humans and nonhuman animals. Exposure of non-diabetic mice to dim LAN impairs glucose tolerance, whereas a return to dark nights (LD) reverses this impairment. We predicted that exposure to LAN would exacerbate the metabolic abnormalities in TALLYHO/JngJ (TH) mice, a polygenic model of type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We exposed 7-week old male TH mice to either LD or LAN for 8-10 weeks in two separate experiments. After 8 weeks of light treatment, we conducted intraperitoneal glucose tolerance testing (ipGTT) followed by intraperitoneal insulin tolerance testing (ipITT). In Experiment 1, all mice were returned to LD for 4 weeks, and ipITT was repeated.

KEY FINDINGS

The major results of this study are i) LAN exposure for 8 weeks exacerbates glucose intolerance and insulin resistance ii) the effects of LAN on insulin resistance are reversed upon return to LD, iii) LAN exposure results in a greater increase in body weight compared to LD exposure, iv) LAN increases the incidence of mice developing overt T2DM, and v) LAN exposure decreases survival of mice with T2DM.

SIGNIFICANCE

In conclusion, LAN exacerbated metabolic abnormalities in a polygenic mouse model of T2DM, and these effects were reversed upon return to dark nights. The applicability of these findings to humans with T2DM needs to be determined.

Phenotypic characterization of a novel type 2 diabetes animal model in a SHANXI MU colony of Chinese hamsters

PURPOSE

Developing animal models for human diseases is critical for studying complex diseases such as type 2 diabetes mellitus (T2DM). Since inbred colonies of Chinese hamsters tend toward spontaneous development of diabetes, we investigated them as a possible model.

METHODS

We regarded individuals with fasting blood glucose (FBG) higher than 6.0 mmol/L and post-prandial blood glucose (PBG) higher than 7.0 mmol/L as diabetic based on the mean and 95% frequency distribution values of FBG and PBG. Diabetic hamsters were characterized based on metabolic profiles, histopathological features, and changes in the expression of genes involved in glucose and lipid metabolism.

RESULTS

Metabolic analyses showed that diabetic hamsters exhibited mild hyperglycemia, hypertriglyceridemia, glucose intolerance, and insulin resistance. Histopathological analysis revealed that cell nuclei migrated inward in skeletal muscle and obvious partial liver lipid deposition and focal necrosis was found. We additionally observed mild injury, atrophy, and occasional vacuolization in islet cells. Changes in the expression of several genes related to glucose and lipid metabolism were observed. Decreased expression of adiponectin and GLUT4 and increased expression of PPARγ, Akt, and leptin was observed in skeletal muscle. Decreased expression of adiponectin with increased expression of PPARγ and leptin was observed in the liver.

CONCLUSIONS

These results indicate that we have established a spontaneous diabetic hamster line that closely mimics human T2DM, which may hold potential for further research on the pathogenesis and treatment of this disease.

Neuroimaging endophenotypes of type 2 diabetes mellitus: a discordant sibling pair study

Background

Type 2 diabetes mellitus (T2DM) is characterized by notable familial aggregation involving common variants of many genes, and its heritability leads to a high prevalence in the siblings of affected individuals compared with the general population. Endophenotypes are objective, heritable, quantitative traits that appear to reflect the genetic risk for polygenic disorders at more biologically tractable levels. Based on a sibling pair design, we aimed to find the neuroimaging endophenotypes of T2DM and investigate the role of inherent neurological disorders in the pathogenesis and deterioration of T2DM.

Methods

Twenty-six pairs of diagnosed T2DM patients with unaffected siblings and 26 unrelated controls were included in this study. Both high-resolution structural MRI and three-dimensional pseudo-continuous arterial spin labelling (3D-pCASL) MRI data were acquired with a 3.0 T MRI system. Voxel-based morphometry (VBM) analysis was performed on the structural T1W images, and cerebral blood flow (CBF) maps were obtained. All data were processed with the SPM8 package under the MATLAB 7.6 operation environment.

Results

The T2DM patients and their unaffected siblings shared significant atrophy in the right inferior/middle temporal gyrus, and left insula, in addition to elevated CBF in the right prefrontal lobe. Several regions with abnormal CBF in siblings, including the right inferior/middle temporal gyrus, left insula, left operculum, right supramarginal gyrus, right prefrontal lobe, and bilateral anterior cingulate cortex, also presented significant atrophy in T2DM patients.

Conclusions

The shared brain regions with grey matter (GM) loss and CBF increases may serve as neuroimaging endophenotypes of T2DM, and the regions with abnormal CBF in siblings indicate an increased risk for T2DM.

Physicians' Perspective on Diabetes Mellitus Management within the Context of Personalized Medicine Era in Tabuk Governorate, Saudi Arabia

BACKGROUND:

Minimizing the number of therapy failures and decreasing the diabetic complications can be achieved by the application of personalising diabetes therapy, based on patient`s genetics, however, currently, personalised Medicine (PM) in diabetes mellitus management is not extensively applied.

AIM:

To assess the knowledge, attitudes, and willingness of physicians in practising of PM in diabetes management.

METHODS:

A cross-sectional analytical study was implemented among 126 physicians from six different governmental hospitals and 12 primary care centres selected by the stratified random sampling technique in the Tabuk region of Saudi Arabia. A structured self-administered questionnaire was utilised for data collection. A simple scoring system (scale of 5 points) was utilised to assess knowledge and willingness. Likert scale was applied to evaluate the attitudes towards practising PM in DM management by the fixed choice response formats.

RESULTS:

The majority of the participants (97.62%) claimed not receiving any PM and/or genomic medicine training. Most of them (82.54%) expressed unsatisfactory knowledge concerning personalised DM, whereas the medium level of attitudes was reported among 57.14% of them and a good level of willingness had been observed among 76.98% of the physicians.

CONCLUSION:

Emphasizing on essential personalised DM management knowledge aspects should be given a considerable priority. Fortunately, positive attitudes and goodwill of physicians towards PM are encouraging and should be supported by policymakers.

Novel murine model of congenital diabetes: The insulin hyposecretion mouse

AIMS/INTRODUCTION

Diabetic animal models have made an enormous contribution to our understanding of the etiology of diabetes and the development of new medications. The aim of the present study was to develop and characterize a novel, non-obese murine strain with spontaneous diabetes - the insulin hyposecretion (ihs) mouse.

MATERIALS AND METHODS

During the development of the ICGN.B6-Tns2WT strain as the control for the ICGN-Tns2nph congenital nephrotic strain, diabetic mice were discovered and named ihs mice. Intraperitoneal insulin tolerance test, oral glucose tolerance test and an insulin secretion experiment by the pancreas perfusion system were carried out on ihs mice. The pancreatic islets were examined histologically, and the mRNA expression of pancreatic β-cell-specific genes or genes associated with monogenic diabetes was examined by RT-qPCR.

RESULTS

The ihs mice showed several distinctive diabetes-related characteristics: (i) the onset of diabetes was observed only in the male mice; (ii) there were no differences in insulin content between the ihs and control mice; (iii) impaired insulin secretion was elicited by glucose, potassium chloride and sulfonylureas; (iv) there was a significant reduction of relative β-cell volume with no signs of inflammation or fibrosis; (v) they showed a normal glycemic response to exogenous insulin; and (vi) the mice were not obese.

CONCLUSIONS

The ihs mouse provides a novel murine model of congenital diabetes that shows insulin secretion failure. This model allows not only an analysis of the progression of diabetes, but also the identification of unknown genes involved in insulin secretion.

Identification of risk factors affecting impaired glucose metabolism among the adult population of district Srinagar

BACKGROUND

The World has seen an emerging trend of diabetes among adolescents and moderately aged people over the last decade. The aim of the study was to identify the risk factors associated with impaired glucose metabolism and the prevalence of impaired glucose metabolism among the adult population of district Srinagar.

METHODS

Multi-stage cluster random sampling design was used and from each household, participants were selected using a Kish grid method. Socio-demographic and clinical data were collected. The participants were then subjected to fasting venous blood glucose estimation.

RESULTS

Age, waist circumference, hip circumference, weight, and body mass index were all statistically significant between normoglycemic participants and those with impaired glucose metabolism (p < 0.018). On logistic regression, subjects who had a higher BMI were more likely to develop Impaired glucose metabolism (OR = 3.52, OR 95% CI = 1.25-9.87); Moreover, consumption of carbonated drinks, (3-6 times/week OR = 4.40, OR 95% CI = 2.06-9.40; >6 times/week OR = 11.04, OR 95% CI = 0.86-140.66) was found to be a potential risk factor. Participants with a family history of diabetes were more susceptible to develop impaired glucose metabolism (OR = 6.41, OR 95% CI = 3.22-12.78). The risk effect of these factors was even stronger before adjusting for age, sex, family history of diabetes, and BMI in participants.

CONCLUSION

Risk factors for impaired glucose metabolism include increasing age, obesity, and higher consumption of carbonated drinks, hypertension, smoking behavior, high-calorie diet intake and positive family history of diabetes.

Established and emerging strategies to crack the genetic code of obesity

Tremendous progress has been made in the genetic elucidation of obesity over the past two decades, driven largely by technological, methodological and organizational innovations. Current strategies for identifying obesity-predisposing loci/genes, including cytogenetics, linkage analysis, homozygosity mapping, admixture mapping, candidate gene studies, genome-wide association studies, custom genotyping arrays, whole-exome sequencing and targeted exome sequencing, have achieved differing levels of success, and the identified loci in aggregate explain only a modest fraction of the estimated heritability of obesity. This review outlines the successes and limitations of these approaches and proposes novel strategies, including the use of exceptionally large sample sizes, the study of diverse ethnic groups and deep phenotypes and the application of innovative methods and study designs, to identify the remaining obesity-predisposing genes. The use of both established and emerging strategies has the potential to crack the genetic code of obesity in the not-too-distant future. The resulting knowledge is likely to yield improvements in obesity prediction, prevention and care.

Type 2 Diabetes-Associated Genetic Polymorphisms as Potential Disease Predictors

Diabetes is a major cause of mortality worldwide. There are several types of diabetes, with type 2 diabetes mellitus (T2DM) being the most common. Many factors, including environmental and genetic factors, are involved in the etiology of the disease. Numerous studies have reported the role of genetic polymorphisms in the initiation and development of T2DM. While genome-wide association studies have identified around more than 200 susceptibility loci, it remains unclear whether these loci are correlated with the pathophysiology of the disease. The present review aimed to elucidate the potential genetic mechanisms underlying T2DM. We found that some genetic polymorphisms were related to T2DM, either in the form of single-nucleotide polymorphisms or direct amino acid changes in proteins. These polymorphisms are potential predictors for the management of T2DM.

Mechanisms of Insulin Action and Insulin Resistance

The 1921 discovery of insulin was a Big Bang from which a vast and expanding universe of research into insulin action and resistance has issued. In the intervening century, some discoveries have matured, coalescing into solid and fertile ground for clinical application; others remain incompletely investigated and scientifically controversial. Here, we attempt to synthesize this work to guide further mechanistic investigation and to inform the development of novel therapies for type 2 diabetes (T2D). The rational development of such therapies necessitates detailed knowledge of one of the key pathophysiological processes involved in T2D: insulin resistance. Understanding insulin resistance, in turn, requires knowledge of normal insulin action. In this review, both the physiology of insulin action and the pathophysiology of insulin resistance are described, focusing on three key insulin target tissues: skeletal muscle, liver, and white adipose tissue. We aim to develop an integrated physiological perspective, placing the intricate signaling effectors that carry out the cell-autonomous response to insulin in the context of the tissue-specific functions that generate the coordinated organismal response. First, in section II, the effectors and effects of direct, cell-autonomous insulin action in muscle, liver, and white adipose tissue are reviewed, beginning at the insulin receptor and working downstream. Section III considers the critical and underappreciated role of tissue crosstalk in whole body insulin action, especially the essential interaction between adipose lipolysis and hepatic gluconeogenesis. The pathophysiology of insulin resistance is then described in section IV. Special attention is given to which signaling pathways and functions become insulin resistant in the setting of chronic overnutrition, and an alternative explanation for the phenomenon of ‟selective hepatic insulin resistanceˮ is presented. Sections V, VI, and VII critically examine the evidence for and against several putative mediators of insulin resistance. Section V reviews work linking the bioactive lipids diacylglycerol, ceramide, and acylcarnitine to insulin resistance; section VI considers the impact of nutrient stresses in the endoplasmic reticulum and mitochondria on insulin resistance; and section VII discusses non-cell autonomous factors proposed to induce insulin resistance, including inflammatory mediators, branched-chain amino acids, adipokines, and hepatokines. Finally, in section VIII, we propose an integrated model of insulin resistance that links these mediators to final common pathways of metabolite-driven gluconeogenesis and ectopic lipid accumulation.

Meta-analysis of association between TCF7L2 polymorphism rs7903146 and type 2 diabetes mellitus

BACKGROUND

Large scale association studies have found a significant association between type 2 diabetes mellitus (T2DM) and transcription factor 7-like 2 (TCF7L2) polymorphism rs7903146. However, the quality of data varies greatly, as the studies report inconsistent results in different populations. Hence, we perform this meta-analysis to give a more convincing result.

METHODS

The articles, published from January 1st, 2000 to April 1st, 2017, were identified by searching in PubMed and Google Scholar. A total of 56628 participants (34232 cases and 22396 controls) were included in the meta-analysis. A total of 28 studies were divided into 4 subgroups: Caucasian (10 studies), East Asian (5 studies), South Asian (5 studies) and Others (8 studies). All the data analyses were analyzed by the R package meta.

RESULTS

The significant association was observed by using the dominant model (OR = 1.41, CI = 1.36 - 1.47, p < 0.0001), recessive model (OR = 1.58, CI = 1.48 - 1.69, p < 0.0001), additive model(CT vs CC) (OR = 1.34, CI = 1.28-1.39, p < 0.0001), additive model(TT vs CC) (OR = 1.81, CI = 1.69-1.94, p < 0.0001)and allele model (OR = 1.35, CI = 1.31-1.39, p < 0.0001).

CONCLUSION

The meta-analysis suggested that rs7903146 was significantly associated with T2DM in Caucasian, East Asian, South Asian and other ethnicities.

Two variants on T2DM susceptible gene HHEX are associated with CRC risk in a Chinese population

Increasing amounts of evidence has demonstrated that T2DM (Type 2 Diabetes Mellitus) patients have increased susceptibility to CRC (colorectal cancer). As HHEX is a recognized susceptibility gene in T2DM, this work was focused on two SNPs in HHEX, rs1111875 and rs7923837, to study their association with CRC. T2DM patients without CRC (T2DM-only, n=300), T2DM with CRC (T2DM/CRC, n=135), cancer-free controls (Control, n=570), and CRC without T2DM (CRC-only, n=642) cases were enrolled. DNA samples were extracted from the peripheral blood leukocytes of the patients and sequenced by direct sequencing. The χ² test was used to compare categorical data. We found that in T2DM patients, rs1111875 but not the rs7923837 in HHEX gene was associated with the occurrence of CRC (p= 0.006). for rs1111875, TC/CC patients had an increased risk of CRC (p=0.019, OR=1.592, 95%CI=1.046-2.423). Moreover, our results also indicated that the two variants of HEEX gene could be risk factors for CRC in general population, independent on T2DM (p< 0.001 for rs1111875, p=0.001 for rs7923837). For rs1111875, increased risk of CRC was observed in TC or TC/CC than CC individuals (p<0.001, OR= 1.780, 95%CI= 1.385-2.287; p<0.001, OR= 1.695, 95%CI= 1.335-2.152). For rs7923837, increased CRC risk was observed in AG, GG, and AG/GG than AA individuals (p< 0.001, OR= 1.520, 95%CI= 1.200-1.924; p=0.036, OR= 1.739, 95%CI= 0.989-3.058; p< 0.001, OR= 1.540, 95%CI= 1.225-1.936). This finding highlights the potentially functional alteration with HHEX rs1111875 and rs7923837 polymorphisms may increase CRC susceptibility. Risk effects and the functional impact of these polymorphisms need further validation.

The rs7903146 Variant in the TCF7L2 Gene Increases the Risk of Prediabetes/Type 2 Diabetes in Obese Adolescents by Impairing β-Cell Function and Hepatic Insulin Sensitivity

OBJECTIVE

In this study, we aimed to explore the mechanism by which TCF7L2 rs7903146 risk allele confers susceptibility to impaired glucose tolerance (IGT) or type 2 diabetes (T2D) in obese adolescents.

RESEARCH DESIGN AND METHODS

The rs7903146 variant in the TCF7L2 gene was genotyped in a multiethnic cohort of 955 youths. All subjects underwent an oral glucose tolerance test with the use of the Oral Minimal Model to assess insulin secretion, and 33 subjects underwent a hyperinsulinemic-euglycemic clamp. In 307 subjects, a follow-up oral glucose tolerance test was repeated after 3.11 ± 2.36 years.

RESULTS

The TCF7L2 rs7903146 risk allele was associated with higher 2-h glucose levels in Caucasians (P = 0.006) and African Americans (P = 0.009), and a trend was seen also in Hispanics (P = 0.072). Also, the T allele was associated with decreased β-cell responsivity and IGT (P < 0.05). Suppression of endogenous hepatic glucose production was lower in subjects with the risk variant (P = 0.006). Finally, the odds of showing IGT/T2D at follow-up were higher in subjects carrying the minor allele (odds ratio 2.224; 95% CI 1.370-3.612; P = 0.0012).

CONCLUSIONS

The rs7903146 variant in the TCF7L2 gene increases the risk of IGT/T2D in obese adolescents by impairing β-cell function, and hepatic insulin sensitivity predicts the development of IGT/T2D over time.

A novel polymorphism in protein kinase AMP-activated catalytic subunit alpha 2 (PRKAA2) is associated with type 2 diabetes in the Han Chinese population

BACKGROUND

It has been proposed that the energy-sensing enzyme AMP-activated protein kinase (AMPK) is a key agent in the pathophysiology of type 2 diabetes mellitus (T2DM). The gene encoding protein kinase AMP-activated catalytic subunit alpha 2 (PRKAA2) is located at one of the Asian T2DM loci (1p32). Therefore, the aim of the present study was to test for the association of common variants in PRKAA2 with T2DM in the Han Chinese population.

METHODS

We genotyped 221 T2DM patients and 111 controls to assess possible associations of two tagging single nucleotide polymorphisms (tSNPs) in the PRKAA2 gene with T2DM.

RESULTS

The clinical characteristics of T2DM cases compared with controls differed significantly. No significant association was observed with the rs2143754 polymorphism whereas the rs2746342 polymorphism exhibited a highly significant association with T2DM. Fasting plasma glucose (FPG) of subjects carrying the G/G genotype of the rs2746342 polymorphism was higher than that of subjects carrying the T allele (P = 0.0049). These associations were magnified in the presence of the G/G genotype of the rs2143754 polymorphism.

CONCLUSIONS

The rs2746342 polymorphism is significantly associated with susceptibility to T2DM and seems to interact with the rs2143754 polymorphism in the modulation of FPG in the Han Chinese population.

FTO Genotype and Type 2 Diabetes Mellitus: Spatial Analysis and Meta-Analysis of 62 Case-Control Studies from Different Regions

Type 2 diabetes mellitus (T2DM) is a global health problem that results from the interaction of environmental factors with genetic variants. Although a number of studies have suggested that genetic polymorphisms in the fat mass and obesity-associated (FTO) gene are associated with T2DM risk, the results have been inconsistent. To investigate whether FTO polymorphisms associate with T2DM risk and whether this association is region-related, we performed this spatial analysis and meta-analysis. More than 60,000 T2DM patients and 90,000 controls from 62 case-control studies were included in this study. Odds ratios (ORs), 95% confidence intervals (CIs) and Moran's I statistic were used to estimate the association between FTO rs9939609, rs8050136, rs1421085, and rs17817499, and T2DM risk in different regions. rs9939609 (OR = 1.15, 95% CI 1.11-1.19) and rs8050136 (OR = 1.14, 95% CI 1.10-1.18) conferred a predisposition to T2DM. After adjustment for body mass index (BMI), the association remained statistically significant for rs9939609 (OR = 1.11, 95% CI 1.05-1.17) and rs8050136 (OR = 1.08, 95% CI 1.03-1.12). In the subgroup analysis of rs9939609 and rs8050136, similar results were observed in East Asia, while no association was found in North America. In South Asia, an association for rs9939609 was revealed but not for rs8050136. In addition, no relationship was found with rs1421085 or rs17817499 regardless of adjustment for BMI. Moran's I statistic showed that significant positive spatial autocorrelations existed in rs9939609 and rs8050136. Studies on rs9939609 and rs8050136 focused on East Asia and South Asia, whereas studies on rs1421085 and rs17817499 were distributed in North America and North Africa. Our data suggest that the associations between FTO rs9939609, rs8050136 and T2DM are region-related, and the two single-nucleotide polymorphisms contribute to an increased risk of T2DM. Future studies should investigate this issue in more regions.

The FOXO1 Gene-Obesity Interaction Increases the Risk of Type 2 Diabetes Mellitus in a Chinese Han Population

Here, we aimed to study the effect of the forkhead box O1-insulin receptor substrate 2 (FOXO1-IRS2) gene interaction and the FOXO1 and IRS2 genes-environment interaction for the risk of type 2 diabetes mellitus (T2DM) in a Chinese Han population. We genotyped 7 polymorphism sites of FOXO1 gene and IRS2 gene in 780 unrelated Chinese Han people (474 cases of T2DM, 306 cases of healthy control). The risk of T2DM in individuals with AA genotype for rs7986407 and CC genotype for rs4581585 in FOXO1 gene was 2.092 and 2.57 times higher than that with GG genotype (odds ratio [OR] = 2.092; 95% confidence interval [CI] = 1.178-3.731; P = 0.011) and TT genotype (OR = 2.571; 95% CI = 1.404-4.695; P = 0.002), respectively. The risk of T2DM in individuals with GG genotype for Gly1057Asp in IRS2 gene was 1.42 times higher than that with AA genotype (OR = 1.422; 95% CI = 1.037-1.949; P = 0.029). The other 4 single nucleotide polymorphisms (SNPs) had no significant association with T2DM (P > 0.05). Multifactor dimensionality reduction (MDR) analysis showed that the interaction between SNPs rs7986407 and rs4325426 in FOXO1 gene and waist was the best model confirmed by interaction analysis, closely associating with T2DM. There was an increased risk for T2DM in the case of non-obesity with genotype combined AA/CC, AA/AC or AG/AA for rs7986407 and rs4325426, and obesity with genotype AA for rs7986407 or AA for rs4325426 (OR = 3.976; 95% CI = 1.156-13.675; P value from sign test [P(sign)] = 0.025; P value from permutation test [P(perm)] = 0.000-0.001). Together, this study indicates an association of FOXO1 and IRS2 gene polymorphisms with T2DM in Chinese Han population, supporting FOXO1-obesity interaction as a key factor for the risk of T2DM.

Diabesity: A Polygenic Model of Dietary-Induced Obesity from Ad Libitum Overfeeding of Sprague–Dawley Rats and Its Modulation by Moderate and Marked Dietary Restriction

This study compared the effects of ad libitum (AL) overfeeding and moderate or marked dietary restriction (DR) on the pathogenesis of a metabolic syndrome of diabesity comprised of age-related degenerative diseases and obesity in a outbred stock of Sprague–Dawley (SD) rats [Crl:CD (SD) IGS BR]. SD rats were fed Purina Certified Rodent Diet AL (group 1), DR at 72–79% of AL (group 2), DR at 68–72% of AL (group 3) or DR at 47–48% of AL (group 4) for 106 weeks. Interim necropsies were performed at 13, 26, and 53 weeks, after a 7-day 5-bromo-2-deoxyuridine (BrdU)-filled minipump implantation. Body weights, organ weights, carcass analysis, in-life data including estrous cyclicity, and histopathology were determined. At 6–7 weeks of age SD rats had 6% body fat. AL-feeding resulted in hypertriglyceridemia, hypercholesterolemia, and dietary-induced obesity (DIO) by study week 14, with 25% body fat that progressed to 36–42% body fat by 106 weeks. As early as 14 weeks, key biomarkers developed for spontaneous nephropathy, cardiomyopathy, and degenerative changes in multiple organ systems. Early endocrine disruption was indicated by changes in metabolic and endocrine profiles and the early development and progression of lesions in the pituitary, pancreatic islets, adrenals, thyroids, parathyroids, liver, kidneys, and other tissues. Reproductive senescence was seen by 9 months with declines in estrous cyclicity and pathological changes in the reproductive organs of both sexes fed AL or moderate DR, but not marked DR. The diabesity syndrome in AL-fed, DIO SD rats was readily modulated or prevented by moderate to marked DR. Moderate DR of balanced diets resulted in a better toxicology model by significantly improving survival, controlling adult body weight and obesity, reducing the onset, severity, and morbidity of age-related renal, endocrine, metabolic, and cardiac diseases. Moderate DR feeding reduces study-to-study variability, increases treatment exposure time, and increases the ability to distinguish true treatment effects from spontaneous aging. The structural and metabolic differences between the phenotypes of DIO and DR SD rats indicated changes of polygenic expression over time in this outbred stock. AL-overfeeding of SD rats produces a needed model of DIO and diabesity that needs further study of its patterns of polygenic expression and phenotype.

Blood sugar level follows perceived time rather than actual time in people with type 2 diabetes

The current study investigates whether perceived time has an effect on blood glucose level in people with type 2 diabetes. The hypothesis is that perceived time will have a greater influence over blood glucose level than actual time. Changes in blood glucose levels were measured in 46 participants with diabetes while they completed simple tasks during a 90-min period. Participants' perception of time was manipulated by having them refer to clocks that were either accurate or altered to run fast or slow. Blood glucose levels changed in accordance with how much time they believed had passed instead of how much time had actually passed. These results are an example of the influence psychological processes can directly exert on the body.

Prevalence of Type II diabetes in District Dir Lower in Pakistan

Objective:

To investigate the prevalence of type II diabetes and pre-diabetes and its risk factors in the District Dir Lower Pakistan.

Methods:

This study was a population based cross--sectional analysis of 1650 individuals of age 20--80 years, using cluster random sampling technique. After an overnight fast, diabetes and pre-diabetes were analyzed according to the World Health Organization recommendation.

Results:

The prevalence of diabetes and prediabetes was 11.1% and 16.0%, respectively. Type II diabetes was found 11.0% in female and 11.2% in male subjects. Stepwise multiple logistic regression showed that growing age, positive family history, body mass index (obesity), hypertension, exercise (less physical activates), education, monthly income, are statistically significant risk factors with type II diabetes.

Conclusion:

Our results suggest that type II diabetes has become a main health problem in District Dir Lower and better strategies are required to handle this problem.

Mitochondrial biogenesis is decreased in skeletal muscle of pig fetuses exposed to maternal high-energy diets

Mitochondria plays an important role in the regulation of energy homeostasis. Moreover, mitochondrial biogenesis accompanies skeletal myogenesis, and we previously reported that maternal high-energy diet repressed skeletal myogenesis in pig fetuses. Therefore, the aim of this study was to evaluate the effects of moderately increased maternal energy intake on skeletal muscle mitochondrial biogenesis and function of the pig fetuses. Primiparous purebred Large White sows were allocated to a normal energy intake group (NE) as recommended by the National Research Council (NRC) and a high energy intake group (HE, 110% of NRC recommendations). On day 90 of gestation, fetal umbilical vein blood and longissimus (LM) muscle were collected. Results showed that the weight gain of sows fed HE diet was higher than NE sows on day 90 of gestation (P<0.05). Maternal HE diet increased fetal umbilical vein serum triglyceride and insulin concentrations (P<0.05), and tended to increase the homeostasis model assessment index (P=0.08). Furthermore, HE fetuses exhibited increased malondialdehyde concentration (P<0.05), and decreased activities of antioxidative enzymes (P<0.05) and intracellular NAD+ level (P<0.05) in LM muscle. These alterations in metabolic traits of HE fetuses were accompanied by reduced mitochondrial DNA amount (P<0.05) and down-regulated messenger RNA expression levels of genes responsible for mitochondrial biogenesis and function (P<0.05). Our results suggest that moderately increased energy supply during gestation decreases mitochondrial biogenesis, function and antioxidative capacity in skeletal muscle of pig fetuses.

Association of ADIPOQ variants with type 2 diabetes mellitus susceptibility in ethnic Han Chinese from northeast China

AIMS/INTRODUCTION

To investigate the association between two single nucleotide polymorphisms (SNPs; rs3774261 and rs822393) in the ADIPOQ gene and type 2 diabetes mellitus in Han Chinese from northeast China.

MATERIALS AND METHODS

The present study comprised 993 type 2 diabetes mellitus patients and 966 unrelated controls from northeastern China. Two SNPs were sequenced using SNPscan. The distribution of genotype frequencies of the two SNPs in ADIPOQ between cases and controls, and in subgroups stratified based on body mass index, were compared using logistic regression analysis. Linear regression was used to analyze the association between each SNP and clinical indicators.

RESULTS

The GG genotype of rs3774261 increased the risk of type 2 diabetes mellitus compared with the AA genotype in participants with a body mass index <24 (P = 0.021; odds ratio 1.636, 95% CI 1.708-2.484). Rs822393 was correlated with glycosylated hemoglobin (P = 0.043) in controls. Rs3774261 had an association with diastolic blood pressure (P = 0.017) in controls, and in controls with a body mass index <24; rs3774261 also had an association with both systolic blood pressure (P = 0.025) and diastolic blood pressure (P = 0.043).

CONCLUSIONS

The present results confirm the association between ADIPOQ variants and type 2 diabetes mellitus in northeastern China. However, additional larger replication studies are required to validate these findings.

Association between single nucleotide polymorphisms of delta/notch-like epidermal growth factor (EGF)-related receptor (DNER) and Delta-like 1 Ligand (DLL 1) with the risk of type 2 diabetes mellitus in a Chinese Han population

The aim of the study was to investigate the association between single nucleotide polymorphisms (SNPs), rs1861612 of delta/notch-like Epidermal Growth Factor (EGF)-related receptor (DNER) and rs1884190 in the Delta-like 1 ligand (DLL1) gene and type 2 diabetes mellitus (T2DM) susceptibility in a Chinese Han population. DNER rs1861612 and DLL1 rs1884190 polymorphisms were genotyped in patients with T2DM and age- and sex-matched T2DM-free controls from a Chinese Han population. A total of 298 patients with T2DM and 500 controls were enrolled in this study. We found that TC and TT genotypes of rs1861612 and variant T were associated with a significantly increased risk of T2DM. In contrast, the AG and AA genotypes of rs1884190 were not significantly associated with the risk of T2DM, even after further stratification analysis based on age or sex. Our results showed that DNER rs1861612 C to T change and variant T genotype may contribute to T2DM in a Chinese Han population.

Polymorphism in microRNA-binding site in HNF1B influences the susceptibility of type 2 diabetes mellitus: a population based case-control study

Background

Recent genome-wide association studies (GWAS) have identified many SNPs associated with type 2 diabetes mellitus (T2DM). However, the functional roles for most of the SNPs have not been elucidated. MicroRNAs (miRNAs) are key regulators of gene expression involved in the development and progression of various diseases including T2DM. In this study, we investigated whether commonly occurring SNPs modulate miRNA-directed regulation of gene expression, and whether such SNPs in miRNA-binding sites are associated with the susceptibility for T2DM.

Methods

Genotypes of eleven 3′ untranslated region (UTR) SNPs of seven susceptibility genes for T2DM were determined in 353 T2DM patients and 448 control subjects. In addition, the interactions of miRNAs with the 3′UTR in the hepatocyte nuclear factor 1β (HNF1B) gene were investigated using luciferase reporter assays.

Results

One 3′UTR SNP (rs2229295) in the HNF1B gene was significantly associated with T2DM, and the frequency of an A allele (rs2229295) in T2DM patients was decreased compared with that in controls. Luciferase reporter assays showed that the SNP (rs2229295) altered the binding of two miRNAs (hsa-miR-214-5p and hsa-miR-550a-5p).

Conclusions

We have detected the interactions of hsa-miR-214-5p/hsa-miR-550a-5p and the 3′UTR SNP of the HNF1B gene by in vitro luciferase reporter assays, and propose that the binding of such miRNAs regulates the expression of the HNF1B gene and the susceptibility of T2DM.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-015-0219-5) contains supplementary material, which is available to authorized users.

Krüppel-like factor 14 increases insulin sensitivity through activation of PI3K/Akt signal pathway

Genome-wide association studies (GWAS) have shown that Krüppel-like factor 14 (KLF14) is associated with type 2 diabetes mellitus (T2DM). However, no report has demonstrated a relationship between KLF14 and glucose metabolism. The aim of this study was to determine whether KLF14 is associated with glucose metabolism and insulin signaling in vitro. The mRNA and protein expressions of KLF14 were determined by Real-time PCR and Western blotting. Glucose uptake was assessed by 2-[(3)H]-deoxyglucose (2-DG) uptake. Western blotting was used to identify the activation of insulin signaling proteins. KLF14 mRNA and protein in fat and muscle were significantly decreased in HFD-fed mice, db/db mice and T2DM patients. Overexpression of KLF14 enhanced insulin-stimulated glucose uptake and the activation of Akt kinase in Hepa1-6 cells. The phosphorylation of insulin receptor (InsR), insulin receptor substrate-1(IRS-1), glycogen synthase kinase-3β (GSK-3β) and Akt also elevated significantly by up-regulation of KLF14. KLF14 overexpression in Hepa1-6 cells prevented the inhibition of glucose uptake and Akt phosphorylation induced by high glucose and/or high insulin, or T2DM serum. However, KLF14's ability to increase glucose uptake and Akt activation was significantly attenuated by LY294002, a PI3-kinase inhibitor. These data suggested that KLF14 could increase insulin sensitivity probably through the PI3K/Akt pathway.

JAZF1 promotes proliferation of C2C12 cells, but retards their myogenic differentiation through transcriptional repression of MEF2C and MRF4-Implications for the role of Jazf1 variants in oncogenesis and type 2 diabetes

Single-nucleotide polymorphisms associated with type 2 diabetes (T2D) have been identified in Jazf1, which is also involved in the oncogenesis of endometrial stromal tumors. To understand how Jazf1 variants confer a risk of tumorigenesis and T2D, we explored the functional roles of JAZF1 and searched for JAZF1 target genes in myogenic C2C12 cells. Consistent with an increase of Jazf1 transcripts during myoblast proliferation and their decrease during myogenic differentiation in regenerating skeletal muscle, JAZF1 overexpression promoted cell proliferation, whereas it retarded myogenic differentiation. Examination of myogenic genes revealed that JAZF1 overexpression transcriptionally repressed MEF2C and MRF4 and their downstream genes. AMP deaminase1 (AMPD1) was identified as a candidate for JAZF1 target by gene array analysis. However, promoter assays of Ampd1 demonstrated that mutation of the putative binding site for the TR4/JAZF1 complex did not alleviate the repressive effects of JAZF1 on promoter activity. Instead, JAZF1-mediated repression of Ampd1 occurred through the MEF2-binding site and E-box within the Ampd1 proximal regulatory elements. Consistently, MEF2C and MRF4 expression enhanced Ampd1 promoter activity. AMPD1 overexpression and JAZF1 downregulation impaired AMPK phosphorylation, while JAZF1 overexpression also reduced it. Collectively, these results suggest that aberrant JAZF1 expression contributes to the oncogenesis and T2D pathogenesis.