Hyperglucagonemia and impaired insulin sensitivity are associated with development of prediabetes and type 2 diabetes - A study from South India.

BACKGROUND AND AIMS: Glucagon levels and glucagon suppression in response to oral glucose load has not been elucidated at different stages of glucose intolerance in India. METHODS: A total of 81 subjects underwent OGTT and were classified into three groups as having normal glucose tolerance (NGT) (n = 23), prediabetes (PreDM) (n = 33), newly diagnosed diabetes (NDM) (n = 25). Insulin and glucagon at fasting, 30 and 120 min was measured by ELISA. HOMA-IR, measures of insulin sensitivity, early, late and overall glucagon suppression during OGTT was calculated. RESULTS: Plasma glucagon levels were higher at all-time points in the PreDM and NDM groups. Fasting glucagon levels were higher than post glucose load glucagon in all groups. There was a significant difference in the fasting(p = 0.001), 30 min(p = 0.004) and 120 min(p = 0.032) glucagon between the groups. HOMA-IR increased and insulin sensitivity decreased with worsening of glucose intolerance(p < 0.0001). The groups did not differ in terms of early glucagon suppression(p = 0.094). NDM group suppressed glucagon more than NGT from 30 to 120 min after glucose intake. CONCLUSION: This study demonstrated higher fasting glucagon levels. Prediabetes and newly diagnosed diabetes individuals had higher glucagon levels, high insulin resistance and lower insulin sensitivity. Hyperglucagonemia may contribute to type 2 diabetes.

Crosstalk between endoplasmic reticulum stress and oxidative stress in the progression of diabetic nephropathy.

Increasing evidence in substantiating the roles of endoplasmic reticulum stress, oxidative stress, and inflammatory responses and their interplay is evident in various diseases. However, an in-depth mechanistic understanding of the crosstalk between the intracellular stress signaling pathways and inflammatory responses and their participation in disease progression has not yet been explored. Progress has been made in our understanding of the cross talk and integrated stress signaling network between endoplasmic reticulum stress and oxidative stress towards the pathogenesis of diabetic nephropathy. In this present study, we studied the crosstalk between the endoplasmic reticulum stress and oxidative stress by understanding the role of protein disulfide isomerase and endoplasmic reticulum oxidase 1α, a key player in redox protein folding in the endoplasmic reticulum. We had recruited a total of 90 subjects and divided into three groups (control (n = 30), type 2 diabetes mellitus (n = 30), and diabetic nephropathy (n = 30)). We found that endoplasmic reticulum stress markers, activating transcription factor 6, inositol-requiring enzyme 1α, protein kinase RNA-like endoplasmic reticulum kinase, C/EBP homologous protein, and glucose-regulated protein-78; oxidative stress markers, thioredoxin-interacting protein and cytochrome b-245 light chain; and the crosstalk markers, protein disulfide isomerase and endoplasmic reticulum oxidase-1α, were progressively elevated in type 2 diabetes mellitus and diabetic nephropathy subjects. The association between the crosstalk markers showed a positive correlation with endoplasmic reticulum stress and oxidative stress markers. Further, the interplay between endoplasmic reticulum stress and oxidative stress was investigated in vitro using a human leukemic monocytic cell line under a hyperglycemic environment and examined the expression of protein disulfide isomerase and endoplasmic reticulum oxidase-1α. DCFH-DA assay and flow cytometry were performed to detect the production of free radicals. Further, phosphorylation of eIF2α in high glucose-exposed cells was studied using western blot. In conclusion, our results shed light on the crosstalk between endoplasmic reticulum stress and oxidative stress and significantly contribute to the onset and progression of diabetic nephropathy and therefore represent the major therapeutic targets for alleviating micro- and macrovascular complications associated with this metabolic disturbance. Graphical abstract.

TCF7L2 polymorphism a prominent marker among subjects with Type-2-Diabetes with a positive family history of diabetes.

The greatest risk of developing type2 diabetes (T2DM) was conferred by rs7903146 SNP of Transcription factor7-like2 (TCF7L2) gene in many ethnic populations. The aim was to investigate the association of TCF7L2 (rs7903146) gene polymorphism among newly diagnosed diabetes subjects with different parental diabetes registry. A total of 171 subjects were categorized into 3 groups based on parental diabetes registry i.e. Conjugal Diabetes Registry (CDR) (n = 50), One Parental Diabetes Registry (OPDR) (n = 56) and Non Parental Diabetes Registry (NPDR) (n = 62) (control group). Kompetitive allele specific PCR (KASP) genotyping assay was used in real time PCR for identifying the genotypes. None of the biochemical parameters showed any significant difference between groups except age at onset of diabetes (p = 0.001). The T allele of TCF7L2 (rs7903146) was associated with significant risk of diabetes. TT genotype which doubles the diabetes risk showed significant association among OPDR whereas in CDR both CT and TT genotypes showed significant association than CC wild type. The 'T' allele of TCF7L2 SNP was associated with significant risk when compared between OPDRvsNPDR (OR 2.45, p = 0.003) and CDRvsNPDR (OR 2.82, p = 0.0007). In conclusion, TCF7L2 gene polymorphism and positive family history of diabetes are strongly associated irrespective of the presence of other risk factors among diabetes subjects.

Efficacy of Recombinant Human Epidermal Growth Factor (Regen-D 150) in Healing Diabetic Foot Ulcers: A Hospital-Based Randomized Controlled Trial.

To validate the efficacy of recombinant human epidermal growth factor (hEGH) in healing diabetic foot ulcers (DFUs) at biochemical and molecular levels. A total of 50 noninfected DFU subjects were recruited for the study and divided into 2 groups based on the treatment application on the subjects. Group 1: DFU subjects treated with hEGH gel-based product called Regen-D 150 (n = 27) and group 2: DFU subjects treated with alternative placebo as the control group (n = 23). Patients were observed for 30 days and punch biopsy was taken at days 0 and 14. Histologic analysis was done to study the matrix alignment, cellular infiltration, and differentiation of epithelial layers. Biochemical analysis was done to quantitatively estimate the amount of collagen and proteoglycans regenerated in the wound area. Complete healing of ulcers was observed in 21 (78%) subjects in group 1, whereas only 12 (52%) subjects among group 2 reported of complete healing of ulcer after completion of the study period of 30 days. Collagen and fibroblasts were significantly developed in group 1 when observed in the follow-up samples. Healing time of the wound among the group 1 subjects was significantly less than the group 2 subjects (45 ± 12 vs 72 ± 18 days, P < .0001) and even showed a better blood glucose level. Early and regular application of the hEGH on DFUs will lead to prevention of leg amputations and would serve to act as a major treatment therapy for healing of chronic wounds.

RANKL Gene Polymorphism as a Potential Biomarker to Identify Acute Charcot Foot Among Indian Population With Type 2 Diabetes: A Preliminary Report.

Studies addressing the link between gene polymorphism and Charcot neuropathic osteoarthopathy (CN) have been limited to analyse osteoprotegerin gene. Aim is to understand the association of RANKL gene variants on the susceptibility of diabetic neuropathy and CN and to measure the serum levels of sRANKL among Indian population with type 2 diabetes. 77 subjects (48 males: 29 females) were recruited and divided into 3 groups. Group 1 Control: normal glucose tolerance (NGT). Group 2: Type 2 diabetes mellitus and neuropathy (DPN). Group 3: Established type 2 diabetes mellitus, DPN, and CN. Subjects were genotyped for RANKL SNP 693 C/G and 643 C/T using polymerase chain reaction-restriction fragment length polymorphism. sRANKL levels were measured using ELISA (enzyme-linked immunosorbent assay). The serum levels of sRANKL were significantly different between the 3 groups. In RANKL -643 C/T the frequency of "CT" genotype and the minor allele "T" was greater among the DPN and CN group compared with the NGT. Further statistical analysis found a significant difference in genotypic frequencies between DPN and NGT subjects with CT genotype. In RANK L -693 C/G the frequency of homozygote mutant "GG" and the minor allele "G" was greater among the DPN and CN group compared with the NGT. Significant differences in genomic frequencies were observed among "GG" genotype. RANKL -643 C/T was significantly associated with DPN alone while -693 C/G was significantly associated with both DPN and CN. Thus, the study suggests RANKL polymorphism might be considered as an independent risk factor for the development of CN.

Seroprevalence and risk factors associated with HBV and HCV infection among subjects with type 2 diabetes from South India.

This is a brief summary of the prevalence on Hepatitis C (HCV) and Hepatitis B (HBV) viral infections and associated risk factors in Type 2 diabetes subjects. Prevalence of HBV (9%) was higher compared to HCV (2%) infection in the screened 388 subjects. Results showed that these infections are independent of the liver damage. Risk factors prominently observed among positive HCV and HBV cases were longer duration of diabetes, hospital admission, history of jaundice and history of surgeries which enlightened the importance of hepatitis vaccination once the subject is diagnosed with diabetes.