DNA methylation and type 2 diabetes: a systematic review.

OBJECTIVE: DNA methylation influences gene expression and function in the pathophysiology of type 2 diabetes mellitus (T2DM). Mapping of T2DM-associated DNA methylation could aid early detection and/or therapeutic treatment options for diabetics. DESIGN: A systematic literature search for associations between T2DM and DNA methylation was performed. Prospero registration ID: CRD42020140436. METHODS: PubMed and ScienceDirect databases were searched (till October 19, 2023). Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and New Castle Ottawa scale were used for reporting the selection and quality of the studies, respectively. RESULT: Thirty-two articles were selected. Four of 130 differentially methylated genes in blood, adipose, liver or pancreatic islets (TXNIP, ABCG1, PPARGC1A, PTPRN2) were reported in > 1 study. TXNIP was hypomethylated in diabetic blood across ethnicities. Gene enrichment analysis of the differentially methylated genes highlighted relevant disease pathways (T2DM, type 1 diabetes and adipocytokine signaling). Three prospective studies reported association of methylation in IGFBP2, MSI2, FTO, TXNIP, SREBF1, PHOSPHO1, SOCS3 and ABCG1 in blood at baseline with incident T2DM/hyperglycemia. Sex-specific differential methylation was reported only for HOOK2 in visceral adipose tissue (female diabetics: hypermethylated, male diabetics: hypomethylated). Gene expression was inversely associated with methylation status in 8 studies, in genes including ABCG1 (blood), S100A4 (adipose tissue), PER2 (pancreatic islets), PDGFA (liver) and PPARGC1A (skeletal muscle). CONCLUSION: This review summarizes available evidence for using DNA methylation patterns to unravel T2DM pathophysiology. Further validation studies in diverse populations will set the stage for utilizing this knowledge for identifying early diagnostic markers and novel druggable pathways.

Landscape of pharmacogenetic variants associated with non-insulin antidiabetic drugs in the Indian population.

INTRODUCTION: Genetic variants contribute to differential responses to non-insulin antidiabetic drugs (NIADs), and consequently to variable plasma glucose control. Optimal control of plasma glucose is paramount to minimizing type 2 diabetes-related long-term complications. India's distinct genetic architecture and its exploding burden of type 2 diabetes warrants a population-specific survey of NIAD-associated pharmacogenetic (PGx) variants. The recent availability of large-scale whole genomes from the Indian population provides a unique opportunity to generate a population-specific map of NIAD-associated PGx variants. RESEARCH DESIGN AND METHODS: We mined 1029 Indian whole genomes for PGx variants, drug-drug interaction (DDI) and drug-drug-gene interactions (DDGI) associated with 44 NIADs. Population-wise allele frequencies were estimated and compared using Fisher's exact test. RESULTS: Overall, we found 76 known and 52 predicted deleterious common PGx variants associated with response to type 2 diabetes therapy among Indians. We report remarkable interethnic differences in the relative cumulative counts of decreased and increased response-associated alleles across NIAD classes. Indians and South Asians showed a significant excess of decreased metformin response-associated alleles compared with other global populations. Network analysis of shared PGx genes predicts high DDI risk during coadministration of NIADs with other metabolic disease drugs. We also predict an increased CYP2C19-mediated DDGI risk for CYP3A4/3A5-metabolized NIADs, saxagliptin, linagliptin and glyburide when coadministered with proton-pump inhibitors (PPIs). CONCLUSIONS: Indians and South Asians have a distinct PGx profile for antidiabetes drugs, marked by an excess of poor treatment response-associated alleles for various NIAD classes. This suggests the possibility of a population-specific reduced drug response in atleast some NIADs. In addition, our findings provide an actionable resource for accelerating future diabetes PGx studies in Indians and South Asians and reconsidering NIAD dosing guidelines to ensure maximum efficacy and safety in the population.

Untargeted Maternal Plasma Metabolomics in Hirschsprung Disease: A Pilot Study.

Background and Aims: Hirschsprung disease (HSCR) is a congenital disorder of unknown etiology affecting the enteric nervous system (ENS). Since the early gestational development of the ENS is dependent on the prenatal maternal metabolic environment, the objective of this pilot study was to explore the role of specific maternal plasma metabolites in the etiology of HSCR. Methods: In this cross-sectional study, postnatal (as a surrogate for prenatal) plasma samples were obtained from mothers of children diagnosed with HSCR (n = 7) and age-matched mothers of normal children (n = 6). The plasma metabolome was analyzed by ultra-high-pressure liquid chromatography and mass spectrometry. Metabolites were identified by mzCloud using Compound Discoverer software. Using an untargeted metabolomics workflow, metabolites with case versus control group differences were identified. Results: A total of 268 unique plasma metabolites were identified and annotated in maternal plasma. Of these, 57 were significantly different between case and control groups (P < 0.05, t-test). Using a false discovery rate corrected cutoff of 10% to adjust for multiple comparisons, 19 metabolites were significantly different in HSCR cases, including carnitines, medium-chain fatty acids, and glutamic acid. Pathways affected were for amino acid and lipid metabolism. Conclusion: Disordered prenatal metabolic pathways may be involved in the etiopathogenesis of HSCR in the developing fetus. This is the first study to assess maternal plasma metabolomics in HSCR.

Evaluation of the expression of genes associated with iron metabolism in peripheral blood mononuclear cells from Type 2 diabetes mellitus patients.

AIMS: Type 2 Diabetes (T2DM) has been linked to ferroptosis. This study aimed to assess expression levels of genes linked with iron metabolism in peripheral blood mononuclear cells (PBMCs) from T2DM patients and to investigate the association of these expression levels with anthropometric and clinical parameters. METHODS: Gene expression of iron metabolism genes (Ferritin Light Chain, FTL; Ferritin Heavy Chain, FTH1; Transferrin Receptor, TFRC; Divalent Metal Transporter 1, SLC11A2; Ferroportin, SLC40A1) in archival PBMCs was assessed using quantitative real-time PCR assays. Correlations of gene expression with anthropometric/biochemical patient data were evaluated. RESULTS: The study included 36 (18 male/18 female) T2DM patients and 45 (28 male/17 female) normoglycemic (NGT) subjects with a mean age of 38.1 ± 6.8 years and 47.6 ± 8.6 years respectively. Relative expression of FTL was significantly lower in T2DM females compared to that in NGT females (P = 0.027). Relative expression of SLC40A1 was significantly lower in the T2DM group (P = 0.043) and in the T2DM females (P = 0.021). Relative expression of SLC11A2 was negatively correlated with systolic blood pressure in T2DM male patients. Relative expression of SLC40A1 was negatively associated with serum phosphorous and positively associated with serum thyroid stimulating hormone in male T2DM patients. CONCLUSIONS: Our findings indicate a reduction in the expression of FTL in perimenopausal T2DM females. Also, in male T2DM patients and NGT subjects, biochemical markers are significantly correlated with the expression of FTL, FTH1, SLC11A2, and SLC40A1 in PBMCs.

Bioavailability and daily requirement of vitamin B12 in adult humans: an observational study of its colonic absorption and daily excretion as measured by [13C]-cyanocobalamin kinetics.

BACKGROUND: Clinical and biochemical vitamin B12 (B12) deficiency is lower than anticipated in vegetarians. Extraileal absorption, such as from the colon, as well as reduced daily excretion, may be adaptive mechanisms to maintain B12 homeostasis with marginal intakes. OBJECTIVE: To measure the absorption of B12 from the small and large intestine, and its daily rate of excretion from the body, using a [13C]-cyanocobalamin tracer. METHODS: Oral B12 bioavailability was measured over 12 h after administration of [13C]-cyanocobalamin tracer (2.5 µg) in normal participants. The colonic B12 bioavailability was evaluated by direct instillation of [13C]-cyanocobalamin (5 µg) into the ascending colon. Bioavailability was calculated from 2-compartmental modeling of the tracer appearance in plasma. The excretion rate of B12 was measured from [13C]-cyanocobalamin elimination from the body over 4 wk after oral dosing (5 µg). RESULTS: The oral B12 bioavailability (n = 11) was 63% ± 10% measured over 12 h. A late absorption peak, accounting for 12% of the absorption, was observed after an average lag time of 8.7 h from dosing. The colonic B12 bioavailability (n = 10) was 7% ± 5% over 4 h. The daily B12 excretion rate (n = 4) was 0.7 ± 0.2 µg/d. The minimum daily requirement of B12 in these participants was derived at 1 µg /d. CONCLUSIONS: B12 is absorbed in the human colon. This observation confirms the potential contribution of the colon in daily B12 nutriture, and along with a possible lower requirement, could explain the absence of clinical deficiency in populations with marginal B12 intakes. TRIAL REGISTRATION NUMBER: This study was registered in Clinical Trials Registry of India (CTRI) with the registration number CTRI/2018/04/012957, available from https://ctri.nic.in/Clinicaltrials/showallp.php?mid1=49319&EncHid=&userName=029108.

The Effect of Zinc Biofortified Wheat Produced via Foliar Application on Zinc Status: A Randomized, Controlled Trial in Indian Children.

BACKGROUND: Agronomic zinc biofortification of wheat by foliar application increases wheat zinc content and total zinc absorption in humans. OBJECTIVES: To assess the effect of agronomically biofortified whole wheat flour (BFW) on plasma zinc (PZC) compared with a postharvest fortified wheat (PHFW) and unfortified control wheat (CW) when integrated in a midday school meal scheme. METHODS: We conducted a 20-wk double-blind intervention trial in children (4-12 y, n = 273) individually randomly assigned to 3 groups to receive a daily school lunch consisting of 3 chapattis prepared with the 3 different wheat flour types. Measurements of anthropometry, blood biochemistry, and leukocyte DNA strand breaks were conducted. We applied sparse serial sampling to monitor PZC over time, and analysis was performed using linear mixed-effects models. RESULTS: Mean zinc content in BFW, PHFW, and CW were 48.0, 45.1, and 21.2 ppm, respectively (P < 0.001). Mean (standard deviation) daily zinc intakes in the study intervention in BFW, PHFW, and CW groups were 4.4 (1.6), 5.9 (1.9) and 2.6 (0.6) mg Zn/d, respectively, with intake in groups PHFW and BFW differing from CW (P < 0.001) but no difference between BFW and PHFW. There were no time effect, group difference, or group × time interaction in PZC. Prevalence of zinc deficiency decreased in the BFW (from 14.1%-11.2%), PHFW (from 8.9%-2.3%), and CW (9.8%-8.8%) groups, but there was no time × treatment interaction in the prevalence of zinc deficiency (P = 0.191). Compliance with consuming the study school meals was associated with PZC (P = 0.006). DNA strand breaks were not significantly associated with PZC (n = 51; r = 0.004, P = 0.945). CONCLUSIONS: Consumption of either PHFW or BFW provided an additional ∼1.8 to 3.3 mg Zn/d, but it did not affect PZC or zinc deficiency, growth, or DNA strand breaks. This trial was registered on clinicaltrials.gov as NCT02241330 and ctri.nic.in as CTRI/2015/06/005913.

Maternal Vitamin A Status as a Risk Factor of Hirschsprung Disease in the Child.

INTRODUCTION: The gene-environment interaction of the REarranged during Transfection ( RET ) gene with vitamin A in the etiopathogenesis of Hirschsprung disease (HSCR) has been suggested in rodents. The aim of this study was to evaluate vitamin A status in mothers of children with HSCR and to assess its association with pathogenic variants of the RET gene in affected children. METHODS: This was a case-control study of stable isotope-based vitamin A measurement stores of mothers of children diagnosed with HSCR (within 8 months from birth, n = 7) and age-matched mothers of normal children (n = 6). Next-generation sequencing of RET exons, along with their upstream promoter region, was performed in the 7 HSCR proband-parent triads to evaluate pathogenic variants. RESULTS: Maternal vitamin A stores in the HSCR group was almost 50% that of those in controls, tending toward significance (0.50 ± 0.17 vs 0.89 ± 0.51 µmol/g respectively, P = 0.079). Two novel pathogenic de novo mutations were identified in 2 cases, and a rare single-nucleotide deletion was detected in the 3.5-kb RET upstream region, in a heterozygous state, in all 7 proband-parent triads. Low-penetrance RET haplotypes associated with HSCR were detected in 5 cases. DISCUSSION: Mothers with children with HSCR had lower vitamin A liver stores than mothers with normal children, and the children who were affected had HSCR despite having no established pathogenic RET variants. Lower maternal vitamin A status may increase the penetrance of genetic mutations in RET , and vitamin-A mediated gene-environment interactions may underpin some of the etiology of HSCR.

Identification of stable reference genes in peripheral blood mononuclear cells from type 2 diabetes mellitus patients.

Reference genes are obligatory for accurate normalization of mRNA transcript levels across samples and experimental conditions in Real Time-polymerase chain reaction (qRT-PCR) based quantitative gene expression assays. Selection of stably expressed reference genes is therefore crucial for ensuring reproducibility of such assays. However, there is a complete dearth of data on stability of commonly used reference genes in Peripheral Blood Mononuclear Cells (PBMCs) from Type 2 diabetes mellitus (T2DM) patients. We have evaluated the gene expression stability of 4 widely used reference genes (Beta-actin, ACTB; Peptidylprolyl Isomerase B, PPIB; Tyrosine 3 Monooxygenase/Tryptophan 5-Monooxygenase Activation Protein Zeta, YWHAZ; and Glyceraldehyde-3-Phosphate Dehydrogenase, GAPDH); in PBMCs from 39 T2DM patients and 47 normoglycemic (NGT) subjects. ACTB and YWHAZ were found to be the most stable genes in PBMCs from T2DM patients and therefore, can be recommended as suitable reference genes in similar contexts. GAPDH and PPIB expressions were not stable in PBMCs from T2DM patients. On using ACTB and YWHAZ as reference genes for measuring relative expression of GAPDH and PPIB in these subjects, relative GAPDH expression was found to be significantly lower in female T2DM patients, compared to female NGT subjects [GAPDH relative normalization unit (RNU): female T2DM (n = 19), median (Q1, Q3): 9.0 (8.1, 9.9); female NGT (n = 18): median (Q1, Q3): 10.1 (9.1, 11.0); P = 0.034]. Dysregulation of GAPDH in PBMCs from female T2DM patients could be associated with sex-specific differences in pathogenesis and outcomes of T2DM.

Intraindividual double burden of malnutrition: The contribution of the infant gut microbiome.

The prevalence of the double burden of malnutrition in society is well known with the coexistence of undernutrition with an increase in overweight/obesity; this has been increasing globally with nutritional imbalances and infectious diseases being the major etiological factors. However, there is also the coexistence of inappropriate adiposity or metabolic dysfunction in an individual who appears currently undernourished by anthropometric standards (stunted or underweight); this is the intraindividual double burden of malnutrition. It could also occur in temporal sequence, as anthropometric overweight in an individual who has previously endured childhood under-nutrition. IIDBM has increased the risk for diet-related non-communicable diseases over the past few decades, as it tracks into adulthood, warranting an urgent need for intervention and prevention. While gut dysbiosis has been associated with various forms of malnutrition, the early life gut microbiome composition and its related metabolites and regulatory factors, are possibly linked to the development of inflammatory and metabolic conditions in IIDBM. The possible underlying physiological mechanisms are reviewed here, working through host dietary influences, gut microbial metabolites, host inflammation and metabolic dysregulation. When validated experimentally and tested through appropriately designed randomised, controlled trials, these mechanistic insights will likely lead to development of preventive strategies.

Placental expression of miR-517-5p and miR-518f-5p: Fetal sex-specific relations with human fetoplacental growth.

OBJECTIVE: We aimed to assess association of chromosome 19 miRNA cluster microRNAs (miR-517-5p and miR-518f-5p) expression with maternal, placental and newborn parameters and with their potential angiogenesis-associated target genes ENG, VEGF and FLT in a set of 68 small- (SGA, n = 30) and appropriate- (AGA, n = 38) for gestational age full-term singleton pregnancies, in relation to fetal sex. STUDY DESIGN: In this retrospective case-control study, placental transcript abundances of miR-517-5p and miR-518f-5p were assessed by real-time quantitative PCR after normalization to reference miRNA, mir-16-5p. Placental transcript abundances of VEGF, FLT and ENG were assessed after normalizing to a set of reference genes. RESULTS: Placental miR-517-5p transcript abundance was negatively associated with birth weight [ß = -88.778, P = 0.006, 95% confidence interval (CI): -151.645, -25.911] and placental weight (ß = -14.683, P = 0.007, 95% CI: -25.254, -4.112) and this association with birth weight was specific to the AGA births (ß = -59.207, P = 0.037, 95% CI: -114.522, -3.891). miR-518f-5p transcript abundance was negatively associated with placental weight (ß = -6.250, P = 0.034, 95% CI: -11.940, -0.559) specifically in the AGA male births (n = 16). Placental VEGF transcript abundance was negatively associated with that of miR-517-5p specifically in SGA female births (n = 14; Spearman's ρ = -0.705, P = 0.005) and with miR-518f-5p transcript abundance specifically in SGA births (Spearman's ρ = -0.437, P = 0.016) and in SGA male births (n = 16; Spearman's ρ = -0.516, P = 0.041). CONCLUSION: We conclude that placental miR-517-5p could be playing a key role in the pathophysiology of fetal growth restriction, which can be potentially targeted through maternal lifestyle modifications for improving fetoplacental growth.

Unique attributes of obesity in India: A narrative review.

Obesity has become a burgeoning epidemic in India, even though the country is still dealing with undernutrition. As a significant determinant of the Metabolic Syndrome (MetS) and non-communicable diseases (NCDs) such as type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD), understanding the Indian context of the problem and learning how to deal with the obesity epidemic in this country has gained paramount importance. This narrative review points to the unique features of the obesity epidemic in India and its associated contributing factors, including the evolving nature of the Indian diet, the peculiarity of the increased adiposity at lower BMIs, unique obesity-associated genetic variants in Indians, the contribution of the gut microbiome, the impact of chronic inflammation and the role of ambient air pollution, and the contribution of decreased physical activity levels concerning the rapid urbanisation and the built environment. We believe that disseminating our insights into these unique features influencing the development of obesity in India will help increase global awareness and pave the way for better control and management of this obesity epidemic.

Variability of human fasted venous plasma metabolomic profiles with tourniquet induced hemostasis.

Venous plasma metabolomics is a potent and highly sensitive tool for identifying and measuring metabolites of interest in human health and disease. Accurate and reproducible insights from such metabolomic studies require extreme care in removing preanalytical confounders; one of these is the duration of tourniquet application when drawing the venous blood sample. Using an untargeted plasma metabolomics approach, we evaluated the effect of varying durations of tourniquet application on the variability in plasma metabolite concentrations in five healthy female subjects. Tourniquet application introduced appreciable variation in the metabolite abundances: 73% of the identified metabolites had higher temporal variation compared to interindividual variation [Intra-Class Correlation (ICC) > 0.50]. As such, we recommend tourniquet application for minimal duration and to wait for 5 min with the needle in situ after removing the tourniquet, to reduce hemostasis-induced variability and false flags in interpretation.

Protocol for a prospective, observational, deep phenotyping study on adipose epigenetic and lipidomic determinants of metabolic homoeostasis in South Asian Indians: the Indian Diabetes and Metabolic Health (InDiMeT) study.

INTRODUCTION: We describe the rationale and broad study design of the Indian Diabetes and Metabolic Health (InDiMeT) study, a new prospective, observational study incorporating extensive epigenetic (DNA methylation) and lipidomic signatures to examine their association with the dysregulation of adipose de novo lipogenesis (DNL) in South Asian Indians. The InDiMeT study aims to use a case-control design to identify genetic and modifiable-environmental-lifestyle associated determinants of (1) epigenomic (DNA methylome) dysregulation of adipose DNL in type 2 diabetes mellitus (T2DM) adipose tissue, (2) identify correlates of epigenomic (DNA methylome) dysregulation of adipose DNL in peripheral blood mononuclear cells (PBMCs) from T2DM subjects and (3) elucidate plasma lipidomic correlates of adipose DNL in T2DM that can be used as biomarkers of adipose tissue dysfunction. METHODS AND ANALYSIS: The InDiMeT study will involve recruitment of 176 normoglycaemic and T2DM individuals who will be undergoing laparoscopic surgery for clinical conditions. Extensive phenotyping of the subjects will be conducted and DNA methylome and lipidomic measurements will be made. The adipose DNL pathway genes are likely to be hypermethylated in patients with T2DM with corresponding reduction of gene expression. Correlates of epigenomic (DNA methylome) dysregulation of adipose DNL pathway in PBMCs and their adipose and plasma lipidomic signatures in T2DM subjects could act as early markers of development of T2DM. ETHICS AND DISSEMINATION: For the InDiMeT study, ethical approval for addressing the specific aims has been obtained from the Institutional Ethics Committee, St John's Medical College and Hospital, St John's National Academy of Health Sciences, Bangalore. Findings from this study will be disseminated through scientific publications in peer-reviewed journals, research conferences and via presentations to stakeholders, patients, clinicians, public and policymakers through appropriate channels.

Gut microbiota profiles of young South Indian children: Child sex-specific relations with growth.

Gut microbiota has been implicated as a modifier of childhood growth. Here, 16S rRNA sequencing-based fecal microbiota profiles of 18-24 month old Indian children were evaluated (n = 41), in relation to their anthropometric parameters, intestinal permeability, body composition and total energy expenditure. Pathway analyses were conducted to assess microbial functions related to stunting, underweight and wasting. The fecal microbiota was enriched in Prevotella 9, Bifidobacterium and Escherichia-Shigella. Weight, weight-for-age Z-scores (WAZ) and weight-for-length Z-scores (WLZ), along with age, acted as covariates of microbiota variation specifically in boys (n = 23). Bifidobacterium longum subsp longum abundance was positively associated with WAZ while Bifidobacterium bifidum and Bifidobacterium breve abundances were negatively associated with age. The lipopolysaccharide biosynthesis pathway was upregulated in stunted (n = 16) and wasted (n = 8) children. Findings from this study indicate that child sex may be a critical modifier of the role of gut microbiota on childhood growth.

Metabolome and microbiome alterations related to short-term feeding of a micronutrient-fortified, high-quality legume protein-based food product to stunted school age children: A randomized controlled pilot trial.

BACKGROUND & AIMS: Stunting in children is a comorbid condition in undernutrition that may be ameliorated by the provision of high-quality foods that provide protein and micronutrients. Addressing this problem in lower social economic environments requires, in part, affordable and scalable food-based solutions with efficacious food products. Towards this end, biochemical/metabolic indicators for fast-throughput screening of foods and their components are desired. A highly acceptable and economical micronutrient-fortified food product with different levels of legume protein was provided to stunted Indian children for one month, to determine change in their linear growth and explore associated biochemical, metabolomic and microbiome indicators. METHODS: A randomized controlled pilot trial was conducted with 100 stunted children (6-10 years of age) to elucidate metabolic and microbiome-based biomarkers associated with linear growth. They were randomized into 4 groups receiving 6, 8, 10 or 12 g of legume-based protein for one month. Anthropometry, blood biochemistry, aminoacidomics, acylcarnitomics and fecal microbiome were measured before and after feeding. RESULTS: No significant differences were observed between groups in height, height-for-age Z-score (HAZ) or BMI-for-age Z-score (BAZ); however, 38 serum metabolites were altered significantly (Bonferroni adjusted P < 0.1) in response to the interventions. IGF-1 (Insulin like Growth Factor-1) was positively (ρ > 0.2, P = 0.02), while serine and ornithine (ρ < -0.2, P = 0.08) were negatively associated with change in height. Leucine, isoleucine and valine positively correlated (P = 0.011, 0.023 and 0.007 respectively) with change in BAZ. Three Operational Taxonomic Units belonging to Bacteroidetes and Firmicutes (VIP score > 1.5) were significantly correlated with change in height. CONCLUSIONS: In this pilot trial, a number of fasting serum metabolomic and fecal microbiome signatures were associated with linear growth after a short-term dietary intervention. The alterations of these markers should be validated in long-term dietary intervention trials as potential screening indicators towards the development of food products that favor growth. This trial was registered at www.ctri.nic.in as CTRI/2016/12/007564.

Placental expression of angiogenesis-related genes and their receptors in IUGR pregnancies: correlation with fetoplacental and maternal parameters.

Objectives: Aberrations in placental vascular development compromising fetal supply of oxygen and essential nutrients can be a significant contributor to intrauterine growth restriction (IUGR). The development of placental vascular tree is under the influence of two families of growth factors, namely the vascular endothelial growth factor (VEGF) family and angiopoietin/TEK family. In this study, we have examined the expression of angiogenesis-related growth factors, mainly VEGF family and angiopoietin-TEK (endothelial-specific receptor tyrosine kinase) family genes in placentae from IUGR pregnancies uncomplicated by preeclampsia (PE) compared to normal pregnancies.Methods: Placentae from normotensive IUGR (n = 42) and appropriate for gestational age (AGA) pregnancies (n = 47) were collected and examined histologically. Clinical parameters were obtained from the medical records. Real-time quantitative PCR was performed to assess placental transcript abundance of VEGF, PGF, FLT1, ANGPT1, ANGPT2, and TEK normalized to a panel of reference genes. Associations of placental transcript abundance of the genes with maternal, placental, and neonatal parameters were tested.Results: Placental transcript abundance for VEGF (relative expression 10.81 versus 12.98, p < .001), PGF (12.14 versus 13.8, p < .001) and ANGPT2 (3.67 versus 9.55, p = .002) were significantly lower in IUGR placentae compared to AGA. The transcript level of VEGF showed significant negative correlation with birth weight (r = -0.419, p = .006), placental weight (r = -0.318, p = .040), placental length (r = -0.389, p = .011) and breadth (r = -0.308, p = .047) only in the IUGR group. Presence of histopathological features of hypoxia correlated with significantly higher transcript levels of PGF in IUGR placentae (12.6 versus 10.9, p = .046).Conclusion: The low levels of VEGF transcripts may be responsible for the impaired angiogenesis in IUGR placentae. The significance of higher relative expression of PGF in the presence of chronic hypoxia needs to be explored.

Acyl ethanolamides in Diabetes and Diabetic Nephropathy: Novel targets from untargeted plasma metabolomic profiles of South Asian Indian men.

The pathophysiology of diabetic nephropathy (DN) in type 2 diabetes (T2D) patients is minimally understood. We compared untargeted high-resolution accurate mass (HRAM) orbitrap-based plasma metabolomic profiles of 31 T2D-DN (with estimated glomerular filtration rate ≤80 mL/min/1.73 m2), 29 T2D and 30 normal glucose tolerance (NGT) Indian men. Of the 939 plasma metabolites that were differentially abundant amongst the NGT, T2D and T2D-DN (ANOVA, False Discovery Rate - FDR adjusted p-value < 0.05), 48 were associated with T2D irrespective of the renal function of the subjects. Acyl ethanolamides and acetylcholine were decreased while monoacylglycerols (MAGs) and cortisol were elevated in both T2D and T2D-DN. Sixteen metabolites, including amino acid metabolites Imidazolelactate and N-Acetylornithine, changed significantly between NGT, T2D and T2D-DN. 192 metabolites were specifically dysregulated in T2D-DN (ratio ≥2 or ≤0.5 between T2D-DN and T2D, similar abundance in NGT and T2D). These included increased levels of multiple acylcarnitine and amino acid metabolites. We observed a significant dysregulation of amino acid and fatty acid metabolism in South Asian Indian male T2D-DN subjects. Unique to this study, we report a reduction in acyl ethanolamide levels in both T2D and T2D-DN males. Those with dysregulation in acyl ethanolamides, which are endogenous agonists of GPR119, are likely to exhibit improved glycemic control with GPR119 agonists.

Introducing a molecular basis to physiology in undergraduate medical education.

Background: Medical professionals in India need to understand the concepts of molecular genetics to stay up-to-date with clinical care as well as to strengthen basic research in the biomedical sciences. Methods: We introduced a modular course on 'Fundamentals in molecular and cellular biology' for first-year medical undergraduate students in the second semester of the first MBBS year in 2015, as part of 'Innovations in teaching physiology' at St John's Medical College. This was a voluntary, add-on course with didactic lectures, hands-on practical classes and a research paper presentation. Evaluation of students' performance in the course took into account their performance in the research paper presentation-based group activity and their attendance for the hands-on practical sessions. Feedback on the content, delivery, evaluation and future improvements of the course was sought from the students. Results: About 65% of students regularly attended the 10-hour long course. Of the students evaluated for the course, 43% achieved the highest, and 11% achieved the lowest grade assigned. Nearly 72% of the students provided feedback on the course. Conclusion: This first outing of the modular course on 'Fundamentals in molecular and cellular biology' generated excitement among the students and achieved some learning for them. It also brought to light hidden challenges in conducting such a voluntary course for medical students in India. Our experience with the course will help in designing a better-integrated course for exposure of first-year medical students to advances in molecular biology and its applied aspects as they progress through the MBBS course.

Combined Vitamin B-12 and Balanced Protein-Energy Supplementation Affect Homocysteine Remethylation in the Methionine Cycle in Pregnant South Indian Women of Low Vitamin B-12 Status.

Background: Low-quality dietary protein intake and vitamin B-12 deficiency could interact to decrease methionine transmethylation and remethylation rates during pregnancy and may affect epigenetic modifications of the fetal genome.Objective: The objective of this randomized, partially open-labeled intervention trial was to examine the effect of supplemental high-quality protein and vitamin B-12 on third-trimester methionine kinetics in pregnant Indian women with a low vitamin B-12 status.Methods: Pregnant women with low serum vitamin B-12 concentrations (<200 pmol/L) were randomly assigned to 1 of 3 groups: the first group received balanced protein-energy supplementation of 500 mL milk/d plus a 10-µg vitamin B-12 tablet/d (M+B-12 group; n = 30), the second group received milk (500 mL/d) plus a placebo tablet (M+P group; n = 30), and the third group received a placebo tablet alone (P group; n = 33). Third-trimester fasting plasma amino acid kinetics were measured by infusing 1-13C,methyl-2H3-methionine, ring-2H5-phenylalanine, ring-2H4-tyrosine,1-13C-glycine, and 2,3,3-2H3,15N-serine in a subset of participants. Placental mRNA expression of genes involved in methionine pathways, placental long interspersed nuclear elements 1 (LINE-1) methylation, and promoter methylation levels of vascular endothelial growth factor (VEGF) were analyzed.Results: Remethylation rates in the M+B-12, M+P, and P groups were 5.1 ± 1.7, 4.1 ± 1.0, and, 5.0 ± 1.4 µmol ⋅ kg-1 ⋅ h-1, respectively (P = 0.057), such that the percentage of transmethylation remethylated to methionine tended to be higher in the M+B-12 group (49.5% ± 10.5%) than in the M+P group (42.3% ± 8.4%; P = 0.053) but neither differed from the P group (44.2% ± 8.1%; P > 0.1). Placental mRNA expression, LINE-1, and VEGF promoter methylation did not differ between groups.Conclusions: Combined vitamin B-12 and balanced protein-energy supplementation increased the homocysteine remethylation rate in late pregnancy. Thus, vitamin B-12 along with balanced protein-energy supplementation is critical for optimal functioning of the methionine cycle in the third trimester of pregnancy in Indian women with low serum vitamin B-12 in early pregnancy. This trial was registered at clinicaltrials.gov as CTRI/2016/01/006578.

Dehydro-alpha-lapachone, a plant product with antivascular activity.

Antivascular agents have become a standard of treatment for many malignancies. However, most of them target the VEGF pathway and lead to refractoriness. To improve the diversity of options for antivascular therapy, we applied a high-throughput screen for small molecules targeting cell adhesion. We then assayed the resulting antiadhesion hits in a transgenic zebrafish line with endothelial expression of EGFP (Tg(fli1:EGFP)(y1)) to identify nontoxic molecules with antivascular activity selective to neovasculature. This screen identified dehydro-α-lapachone (DAL), a natural plant product. We found that DAL inhibits vessel regeneration, interferes with vessel anastomosis, and limits plexus formation in zebrafish. Furthermore, DAL induces vascular pruning and growth delay in orthotopic mammary tumors in mice. We show that DAL targets cell adhesion by promoting ubiquitination of the Rho-GTPase Rac1, which is frequently up-regulated in many different cancers.