Type I diabetes mellitus: genetic factors and presumptive enteroviral etiology or protection

Covid-19 infection in children and adolescents and its association with type 1 diabetes mellitus (T1d) presentation and management

Children seem to be affected by the new SARS-CoV-2 virus less severely than adults, with better prognosis and low mortality. Serious complications of COVID-19 infection in children include multisystem inflammatory response syndrome in COVID-19 infection (MIS-C), myo-or pericarditis and, less frequently, long COVID syndrome. On the other hand, adults with type 1 (T1D) or type 2 diabetes (T2D) are among the most vulnerable groups affected by COVID-19, with increased morbidity and mortality. Moreover, an association of SARS-CoV-2 with diabetes has been observed, possibly affecting the frequency and severity of the first clinical presentation of T1D or T2D, as well as the development of acute diabetes after COVID-19 infection. The present review summarizes the current data on the incidence of T1D among children and adolescents during the COVID-19 pandemic, as well as its severity. Moreover, it reports on the types of newly diagnosed diabetes after COVID infection and the possible pathogenetic mechanisms. Additionally, this study presents current data on the effect of SARS-CoV-2 on diabetes control in patients with known T1D and on the severity of clinical presentation of COVID infection in these patients. Finally, this review discusses the necessity of immunization against COVID 19 in children and adolescents with T1D.

Contribution of Retrotransposons to the Pathogenesis of Type 1 Diabetes and Challenges in Analysis Methods

Type 1 diabetes (T1D) is one of the most common chronic diseases of the endocrine system, associated with several life-threatening comorbidities. While the etiopathogenesis of T1D remains elusive, a combination of genetic susceptibility and environmental factors, such as microbial infections, are thought to be involved in the development of the disease. The prime model for studying the genetic component of T1D predisposition encompasses polymorphisms within the HLA (human leukocyte antigen) region responsible for the specificity of antigen presentation to lymphocytes. Apart from polymorphisms, genomic reorganization caused by repeat elements and endogenous viral elements (EVEs) might be involved in T1D predisposition. Such elements are human endogenous retroviruses (HERVs) and non-long terminal repeat (non-LTR) retrotransposons, including long and short interspersed nuclear elements (LINEs and SINEs). In line with their parasitic origin and selfish behaviour, retrotransposon-imposed gene regulation is a major source of genetic variation and instability in the human genome, and may represent the missing link between genetic susceptibility and environmental factors long thought to contribute to T1D onset. Autoreactive immune cell subtypes with differentially expressed retrotransposons can be identified with single-cell transcriptomics, and personalized assembled genomes can be constructed, which can then serve as a reference for predicting retrotransposon integration/restriction sites. Here we review what is known to date about retrotransposons, we discuss the involvement of viruses and retrotransposons in T1D predisposition, and finally we consider challenges in retrotransposons analysis methods.

Phosphorylation of enteroviral 2Apro at Ser/Thr125 benefits its proteolytic activity and viral pathogenesis

Enteroviral 2A proteinase (2A^pro ), a well-established and important viral functional protein, plays a key role in shutting down cellular cap-dependent translation, mainly via its proteolytic activity, and creating optimal conditions for Enterovirus survival. Accumulated data show that viruses take advantage of various signaling cascades for their life cycle; studies performed by us and others have demonstrated that the extracellular signal-regulated kinase (ERK) pathway is essential for enterovirus A71 (EV-A71) and other viruses replication. We recently showed that ERK1/2 is required for the proteolytic activity of viral 2A^pro ; however, the mechanism underlying the regulation of 2A^pro remains unknown. Here, we demonstrated that the 125th residue Ser125 of EV-A71 2A^pro or Thr125 of coxsackievirus B3 2A^pro , which is highly conserved in the Enterovirus, was phosphorylated by ERK1/2. Importantly, 2A^pro with phosphor-Ser/Thr125 had much stronger proteolytic activity toward eukaryotic initiation factor 4GI and rendered the virus more efficient for multiplication and pathogenesis in hSCARB2 knock-in mice than that in nonphospho-Ser/Thr125A (S/T125A) mutants. Notably, phosphorylation-mimic mutations caused deleterious changes in 2A^pro catalytic function (S/T125D/E) and in viral propagation (S125D). Crystal structure simulation analysis showed that Ser125 phosphorylation in EV-A71 2A^pro enabled catalytic Cys to adopt an optimal conformation in the catalytic triad His-Asp-Cys, which enhances 2A^pro proteolysis. Therefore, we are the first to report Ser/Thr125 phosphorylation of 2A^pro increases enteroviral adaptation to the host to ensure enteroviral multiplication, causing pathogenicity. Additionally, weakened viruses containing a S/T125A mutation could be a general strategy to develop attenuated Enterovirus vaccines.

Environmental Factors and the Risk of Developing Type 1 Diabetes-Old Disease and New Data

Simple Summary

Despite many studies, the risk factors of type 1 diabetes (T1DM) in children and adolescents are still not fully understood and remain a big challenge. Therefore, an extensive online search for scientific research on factors related to diabetes has been performed for the identification of new factors of unexplained etiology. A better understanding of the role of viral, bacterial, and yeast-like fungi infections related to the risk of T1DM in children and adolescents and the identification of new risk factors, especially those spread by the droplet route, is of great importance for people and families with diabetes.

Abstract

The incidence of type 1 diabetes (T1D) is increasing worldwide. The onset of T1D usually occurs in childhood and is caused by the selective destruction of insulin-producing pancreatic islet cells (β-cells) by autoreactive T cells, leading to insulin deficiency. Despite advanced research and enormous progress in medicine, the causes of T1D are still not fully understood. Therefore, an extensive online search for scientific research on environmental factors associated with diabetes and the identification of new factors of unexplained etiology has been carried out using the PubMed, Cochrane, and Embase databases. The search results were limited to the past 11 years of research and discovered 143 manuscripts published between 2011 and 2022. Additionally, 21 manuscripts from between 2000 and 2010 and 3 manuscripts from 1974 to 2000 were referenced for historical reference as the first studies showcasing a certain phenomenon or mechanism. More and more scientists are inclined to believe that environmental factors are responsible for the increased incidence of diabetes. Research results show that higher T1D incidence is associated with vitamin D deficiency, a colder climate, and pollution of the environment, as well as the influence of viral, bacterial, and yeast-like fungi infections. The key viral infections affecting the risk of developing T1DM are rubella virus, mumps virus, Coxsackie virus, cytomegalovirus, and enterovirus. Since 2020, i.e., from the beginning of the COVID-19 pandemic, more and more studies have been looking for a link between Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and diabetes development. A better understanding of the role of viral, bacterial, and yeast-like fungi infections related to the risk of T1DM in children and adolescents and the identification of new risk factors, especially those spread by the droplet route, is of great importance for people and families with diabetes.

Trends in Diabetes Mortality in Urban and Rural China, 1987-2019: A Joinpoint Regression Analysis

Purpose

Diabetes mellitus is emerging as an epidemic worldwide, and the incidence and prevalence of diabetes have drastically changed in China over the past 30 years, but data on its mortality rate are scarce. This study aimed to analyze the time trends of mortality rates among patients with diabetes in the rural and urban population in China between 1987 and 2019.

Methods

The research data come from China's annual report on national health statistics and the Chinese Health Statistics Yearbook. Age-standardized mortality rates were calculated by using the direct method based on the World Standard Population from the WHO. Joinpoint regression analysis was employed to estimate the annual percent change and average annual percentage changes of mortality rates of diabetes mellitus.

Results

An overall trend for increment in diabetes mortality was observed. The crude mortality rates and age-standardized mortality rates of diabetes for urban and rural residents in China showed a significant increasing trend between 1987 and 2019. Mortality due to diabetes in urban areas has been higher than in rural areas for 30 years. However, due to the rapid increase of rural diabetes mortality in the past decade, the gap between the two gradually narrowed. The age-standardized mortality rates of diabetes increased by about 38.5% in urban areas and 254.9% in rural areas over the whole study period. In addition, the age-standardized mortality rate of females with diabetes was higher than that of males, but this pattern began to change in urban areas in 2012. Finally, the age-standardized mortality rates in the elderly population in China are higher with a faster growth rate, especially in rural areas.

Conclusion

The mortality rate of diabetes is on the rise in China. The rapid growth of the mortality rate of diabetes in rural areas leads to the reduction of the urban-rural gap. Male mortality rates in urban areas have surpassed those of women. At the same time, the mortality rate of diabetes showed obvious elder-group orientation. As China's population ages, the burden of death and disability caused by diabetes and its complications will continue to increase. These results indicate that diabetes has become a significant public health problem in China. Such an effect increases the demand for strategies aimed at the prevention and treatment of diabetes mellitus. In addition to the prevention and intervention of diabetes in high-risk groups, it is also necessary to establish diabetes screening networks to identify patients with mild symptoms. Early detection and timely intervention can effectively reduce the incidence and mortality of diabetes.

Study protocol of a randomized controlled clinical trial investigating the effects of omega-3 supplementation on endothelial function, vascular structure, and metabolic parameters in adolescents with type 1 diabetes

Background

Type 1 diabetes is a main health burden with several related comorbidities. It has been shown that endothelial function, vascular structure, and metabolic parameters are considerably disrupted in patients with type 1 diabetes. Omega-3 as an adjuvant therapy may exert profitable effects on type 1 diabetes and its complications by improving inflammation, oxidative stress, immune responses, and metabolic status. Because no randomized clinical trial has examined the effects of omega-3 consumption in children and adolescents with type 1 diabetes; the present study aims to close this gap.

Methods

This investigation is a randomized clinical trial, in which sixty adolescents with type 1 diabetes will be randomly assigned to receive either omega-3 (600 mg/day) or placebo capsules for 12 weeks. Evaluation of anthropometric parameters, flow-mediated dilation (FMD) as an endothelial function marker, carotid intima-media thickness (CIMT) as a vascular structure marker, proteinuria, biochemical factors including glycemic and lipid profile, blood urea nitrogen (BUN), creatinine, high-sensitivity C-reactive protein (hs-CRP), and erythrocyte sedimentation rate (ESR), as well as blood pressure will be done at the baseline and end of the trial. Also, dietary intake and physical activity will be assessed throughout the study. Statistical analysis will be performed using the SPSS software (Version 24), and P < 0.05 will be considered statistically meaningful.

Discussion

It is hypothesized that omega-3 supplementation may be beneficial for the management of type 1 diabetes and its complications by reducing inflammation and oxidative stress and also modulating immune responses and glucose and lipid metabolism through various mechanisms. The present study aims to investigate any effect of omega-3 on patients with type 1 diabetes.

Ethical aspects

This trial received approval from Medical Ethics Committee of Iran University of Medical Sciences, Tehran, Iran (IR.IUMS.REC.1400.070).

Trial registration

Iranian Registry of Clinical Trials IRCT20210419051010N1. Registered on 29 April 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05930-1.

Coxsackievirus B4 sewage-isolate induces pancreatitis after oral infection of mice

Numerous serotypes which belong to the genus Enterovirus (EV) show variability in their virulence and clinical manifestations. They are also known to undergo changes caused by mutations and recombination during their circulation in the environment and the population. Various EV serotypes are prevalent in groundwater, wastewater and surface waters. Our previous studies showed that oral infection induces pancreatitis depending on specific conditions, such as gravidity, in an outbred murine model. Our aim in the present study was to further explore the pancreatic histopathology in an outbred mouse model following oral infection with clinical isolates from a patient who had aseptic meningitis and an isolate from a treated-sewage sample recovered from the residential area of the patient. The isolates were identified as coxsackievirus B4 (CVB4) in tissue culture. The CVB4 sewage-isolate induced pancreatitis after oral infection. In contrast, pancreatitis was absent following infection with the clinical isolates. Comparison of polyprotein sequences showed that the treated-sewage strains differed from the patient's isolates by 9 and 11 amino acids. We conclude that the isolates of clinical and environmental origin differed in their pathogenic properties and showed genetic variation.

Prevalence of celiac disease in children with type 1 diabetes: A review

BACKGROUND AND AIMS

Diabetes mellitus is a chronic disease and a major health threat. Comorbidity of celiac disease and diabetes is associated with many complications in children, and if not diagnosed in time in diabetes children, caused complications, including gastrointestinal disorders, most importantly, growth disorders. Thus, this study aims to summarize the evidence about prevalence of celiac disease in children with type 1 diabetes through a systematic review approach.

METHODS

A literature review was conducted within databases. Observational studies that assessed the prevalence of celiac disease in diabetes children, were included. We assess the quality of included studies with STROBE checklist. Data extraction and assessment has guided by PRISMA checklist. Also, the data has reported by Garrard's table.

RESULTS

31 studies included that assessed 63,349 children with type 1 diabetes. Anemia, osteoporosis, and neurological disorders reported. Studies showed two main type of tests for diagnosis of CD included serological and intestinal biopsy. The prevalence of CD based serologic tests was higher than of intestine biopsy (1.4%-24.5% VS 1.1%-16.6%). In addition, the prevalence of celiac disease was different between populations.

CONCLUSIONS

Celiac disease is an important comorbidity in children with type 1 diabetes, especially because of the similarity between CD symptoms and neuropathic and gastrointestinal symptoms of diabetes. Screening the diabetes children for celiac disease by serological tests and then intestinal biopsy is recommended.

Implication of epigenetic factors in the pathogenesis of type 1 diabetes

Type 1 diabetes (T1D) is an autoimmune disease that resulted from the severe destruction of the insulin-producing β cells in the pancreases of individuals with a genetic predisposition. Genome-wide studies have identified HLA and other risk genes associated with T1D susceptibility in humans. However, evidence obtained from the incomplete concordance of diabetes incidence among monozygotic twins suggests that environmental factors also play critical roles in T1D pathogenesis. Epigenetics is a rapidly growing field that serves as a bridge to link T1D risk genes and environmental exposures, thereby modulating the expression of critical genes relevant to T1D development beyond the changes of DNA sequences. Indeed, there is compelling evidence that epigenetic changes induced by environmental insults are implicated in T1D pathogenesis. Herein, we sought to summarize the recent progress in terms of epigenetic mechanisms in T1D initiation and progression, and discuss their potential as biomarkers and therapeutic targets in the T1D setting.

Diabetes and COVID-19: A systematic review on the current evidences

BACKGROUND

COVID-19 pneumonia is a newly recognized illness that is spreading rapidly around the world and causes many disability and deaths. Some diseases, for instance diabetes, is continuously suggested as a risk factor which contributes to the severity and mortality of COVID-19. However, to date, there are no comprehensive studies aiming to explain the exact relationship between diabetes and COVID-19. Thus, this study aims to summarize the evidence about diabetes and COVID-19 outbreak through a systematic review and meta-analysis approach.

METHOD

A literature review was implemented within databases of Scopus, PubMed, Science direct, and Web of science. Observational reviews, case-report, and case-series studies that assessed the diabetes in COVID-19 patients, were included. Data extraction and assessment were guided by PRISMA checklist.

FINDINGS

Some studies suggest that there were no significant differences in symptoms between patients who suffered from both diabetes and COVID-19 and those who only suffered COVID-19. In the subsequent meta-analysis 14.5% of the subjects were diabetic patient. These clients have poor ARDS prognosis, severe symptoms, and the death rate is higher among COVID-19 patients. In addition, it is suggested the diabetic patients will be treated with antibiotics, antivirals, and HCQ.

CONCLUSION

The results of this study show that diabetes is a risk factor - and contributes to the severity and mortality of patients with COVID-19. This paper also provides recommendations and guidelines for which could be useful for prevention and treatment of diabetic patients affected by COVID-19.

Health Benefits of Endurance Training: Implications of the Brain-Derived Neurotrophic Factor-A Systematic Review

This article presents a concept that wide expression of brain-derived neurotrophic factor (BDNF) and its receptors (TrkB) in the nervous tissue, evoked by regular endurance training (ET), can cause numerous motor and metabolic adaptations, which are beneficial for human health. The relationships between the training-evoked increase of endogenous BDNF and molecular and/or physiological adaptations in the nervous structures controlling both motor performance and homeostasis of the whole organism have been presented. Due to a very wide range of plastic changes that ET has exerted on various systems of the body, the improvement of motor skills and counteraction of the development of civilization diseases resulting from the posttraining increase of BDNF/TrkB levels have been discussed, as important for people, who undertake ET. Thus, this report presents the influence of endurance exercises on the (1) transformation of motoneuron properties, which are a final element of the motor pathways, (2) reduction of motor deficits evoked by Parkinson disease, and (3) prevention of the metabolic syndrome (MetS). This review suggests that the increase of posttraining levels of BDNF and its TrkB receptors causes simultaneous changes in the activity of the spinal cord, the substantia nigra, and the hypothalamic nuclei neurons, which are responsible for the alteration of the functional properties of motoneurons innervating the skeletal muscles, for the enhancement of dopamine release in the brain, and for the modulation of hormone levels involved in regulating the metabolic processes, responsively. Finally, training-evoked increase of the BDNF/TrkB leads to a change in a manner of regulation of skeletal muscles, causes a reduction of motor deficits observed in the Parkinson disease, and lowers weight, glucose level, and blood pressure, which accompany the MetS. Therefore, BDNF seems to be the molecular factor of pleiotropic activity, important in the modulation processes, underlying adaptations, which result from ET.

Helminths protect against type 1 diabetes: effects and mechanisms

Type 1 diabetes (T1D) is an autoimmune disease in which cells of the immune system destroy pancreatic β cells, which secrete insulin. The high prevalence of T1D in developed societies may be explained by environmental changes, including lower exposure to helminths. Indeed, infection by helminths such as Schistosoma, Filaria, and Heligmosomoides polygyrus and their by-products has been reported to ameliorate or prevent the development of T1D in human and animal models. Helminths can trigger distinct immune regulatory pathways, often involving adaptive immune cells that include T helper 2 (Th2) cells and regulatory T cells (Tregs) and innate immune cells that include dendritic cells, macrophages, and invariant natural killer T cells, which may act synergistically to induce Tregs in a Toll-like receptor-dependent manner. Cytokines such as interleukin (IL)-4, IL-10, and transforming growth factor (TGF)-β also play an important role in protection from T1D. Herein, we provide a comprehensive review of the effects and mechanisms underlying protection against T1D by helminths.

Environmental Factors Associated With Type 1 Diabetes

Type 1 diabetes (T1D) is a chronic autoimmune disorder that leads to progressive pancreatic ß-cell destruction and culminates in absolute insulin deficiency and stable hyperglycaemia. It is very likely that environmental factors play a role in triggering islet autoimmunity. Knowing whether they have true relevance in favoring T1D development is essential for the effective prevention of the disease. Moreover, prevention could be obtained directly interfering with the development of autoimmunity through autoantigen-based immunotherapy. In this narrative review, the present possibilities for the prevention of T1D are discussed. Presently, interventions to prevent T1D are generally made in subjects in whom autoimmunity is already activated and autoantibodies against pancreatic cell components have been detected. Practically, the goal is to slow down the immune process by preserving the normal structure of the pancreatic islets for as long as possible. Unfortunately, presently methods able to avoid the risk of autoimmune activation are not available. Elimination of environmental factors associated with T1D development, reverse of epigenetic modifications that favor initiation of autoimmunity in subjects exposed to environmental factors and use of autoantigen-based immunotherapy are possible approaches, although for all these measures definitive conclusions cannot be drawn. However, the road is traced and it is possible that in a not so distant future an effective prevention of the disease to all the subjects at risk can be offered.

An Overview on Probiotics as an Alternative Strategy for Prevention and Treatment of Human Diseases

Probiotics are viable and useful microorganisms, which are beneficial factors for human and animal health by altering their microbial flora. Most of the probiotics belong to a large group of bacteria in the human gastrointestinal tract. There are several clinical shreds of evidence that show anti-carcinogenic effects of probiotics through altering digestive enzymes, inhibition of carcinogenic agents, and modulating the immune responses in experimental animals. Many studies have been performed to evaluate the potential effectiveness of probiotics in treating or preventing neurological diseases such as MS and novel treatment modality for T1D. The purpose of this study is to have an overview on probiotic microorganisms and to review the previous researches on the effects of probiotics on health through currently available literatures. The study was performed using following keywords; Probiotics, Cancer, Immune system, Multiple Sclerosis (MS) and Diabetes mellitus. PubMed/Medline, Clinicaltrials.gov, Ovid, Google Scholar, and Reaxcys databases used to find the full text of related articles. According to the current available data on probiotics and related health-promoting benefits, it seems that, consumption of probiotics can lead to the prevention and reduction the risk of cancer, diabetes, and multiple sclerosis. Although for the better and more decisive conclusion, there is a need to larger sample size clinical studies with more focus on the safety of these biological agents and their possible beneficial effects on different population.

Assessment of a swab collection method without virus transport medium for PCR diagnosis of coxsackievirus infections

Classically, detection of human enterovirus (EV) infections is based on virus isolation in tissue culture, proper sample collection and handling that optimizes virus viability. Samples are collected in virus transport medium (VTM) to ensure virus stability. High sensitivity and rapid results have made polymerase chain reaction (PCR) analysis increasingly popular for routine diagnosis. The PCR method enables simple sample collection and storage for EV diagnostics, which may eventually allow self-sampling at home. Our aim was to test a modification of the conventional clinical swab sample collection method for molecular diagnosis of EV infection. We compared swabs (cotton or synthetic) without VTM and the classical standard synthetic swabs with VTM. Effects of storage temperature (+4 ^°C or -80 ^°C) and duration were studied. EV-RNA could be detected by reverse transcriptase and nested PCR in both swab types without VTM. Differences depended on the storage duration and temperature. Optimum conditions were immediate processing or storage at -80 ^°C. Storage without VTM at +4 ^°C for longer periods is not advisable. We conclude that swabs without VTM can be considered for clinical EV-diagnostics based on PCR, and ultimately for epidemiological sample collection.

Obestatin can potentially differentiate Wharton's jelly mesenchymal stem cells into insulin-producing cells

In vitro-generation of β-cells from Wharton's jelly mesenchymal stem cells (WJ-MSCs) could provide a potential basis for diabetes mellitus cell therapy. However, the generation of functional insulin-producing cells (IPCs) from WJ-MSCs remains a challenge. Recently, obestatin, a gut hormone, was found to promote β-cell generation from pancreatic precursor cells. Accordingly, we hypothesize that obestatin can induce the differentiation of WJ-MSCs into IPCs. Therefore, the purpose of the current study is to examine the ability of obestatin to generate IPCs in comparison to well-known extrinsic factors that are commonly used in IPCs differentiation protocols from MSCs, namely exendin-4 and glucagon-like peptide-1 (GLP-1). To achieve our aims, WJ-MSCs were isolated, cultured and characterized by immunophenotyping and adipocytes differentiation. Afterwards, WJ-MSCs were induced to differentiate into IPCs using two differentiation protocols incorporating either exendin-4, GLP-1 or obestatin. The pancreatic progenitor marker, nestin and β-cell differentiation markers were assessed by qRT-PCR, while the functionality of the generated IPCs was assessed by glucose-stimulated insulin secretion (GSIS). Our results showed that WJ-MSCs exhibit all the characteristics of MSCs. Interestingly, using obestatin in both the short and long differentiation protocols managed to induce the expression of β-cell markers, similar to exendin-4. In GSIS, IPCs generated using either GLP-1 or obestatin showed higher secretion of insulin as compared to those generated using exendin-4 under low-glucose conditions but failed to show a significant response to increased glucose. These results indicate obestatin can be considered as a novel potential factor to consider for generation of IPCs from WJ-MSCs.

Recognizing type 1 diabetes mellitus in children & adolescents

The common chief complaint of abdominal pain, nausea, and vomiting should prompt a broad differential diagnosis list. When a 17-year-old previously healthy male presented to a primary care clinic with these symptoms, it provoked a detailed workup and found a startling diagnosis of type 1 diabetes mellitus (T1DM). This article provides an overview of recognizing T1DM in children and adolescents with a thorough and diagnostic evaluation.

Dynamics of diabetes and obesity: Epidemiological perspective

The purpose of this review article is to understand the current literature on obesity, diabetes and therapeutic avenues across the world. Diabetes is a chronic lifestyle condition that affects millions of people worldwide and it is a major health concern in our society. Diabetes and obesity are associated with various conditions, including non-modifiable and modifiable risk factors. Early detectable markers are not well established to detect pre-diabetes and as a result, it becomes diabetes. Several published epidemiological studies were assessed and the findings were summarized. Resources from published studies were used to identify criteria used for pre-diabetes, the role of diet in pre-diabetics and potential risks and characteristics associated with pre-diabetes. Preventive strategies are needed to combat diabetes. Individuals diagnosed with pre-diabetes need detailed education, need to fully understand the risk factors and have the ability to manage diabetes. Interventions exist that include chronic disease self-management programs, lifestyle interventions and pharmacological strategies. Obesity plays a large role in causing pre-diabetes and diabetes. Critical analysis of existing epidemiological research data suggests that additional research is needed to determine the efficacy of interventions. This article is part of a Special Issue entitled: Oxidative Stress and Mitochondrial Quality in Diabetes/Obesity and Critical Illness Spectrum of Diseases - edited by P. Hemachandra Reddy.

Integrated analysis of different microarray studies to identify candidate genes in type 1 diabetes

BACKGROUND

Type 1 diabetes (T1D), an autoimmune disease, occurs most commonly in children. Identifying altered gene expression in peripheral blood mononuclear cells (PBMCs) of T1D may lead to new strategies for preserving or improving β-ell function in patients with T1D.

METHODS

The Gene Expression Omnibus database was searched for microarray studies in PBMCs of T1D. Subsequently, gene expression datasets from multiple microarray studies were integrated to obtain differentially expressed genes (DEGs) between T1D and normal controls (NC). Gene function analysis was performed to determine the functions of the DEGs identified.

RESULTS

Four microarray studies were available for analysis, including 199 T1D samples and 74 NC samples. Analysis revealed 695 genes that were significantly differentially expressed in PBMCs from T1D compared with NC samples, with 450 upregulated and 245 downregulated. Signal transduction (gene ontology [GO]: 0007165; false discovery rate [FDR] = 1.54 × 10^-7 ) and protein binding (GO: 0005515; FDR = 2.93 × 10^-24 ) were significantly enriched for the GO categories of biological processes and molecular functions, respectively. The most significant pathway in the Kyoto Encyclopedia of Genes and Genomes analysis was arachidonic acid metabolism (FDR = 1.44 × 10^-3 ). Protein-protein interaction network analysis showed that the significant hub proteins contained immature colon carcinoma transcript 1 (ICT1; degree = 214; clustering coefficient [C] = 4.39 × 10^-5 ), zinc finger and BTB domain containing 16 (ZBTB16; degree = 112; C = 8.04 × 10^-4 ), and SERTA domain containing 1 (SERTAD1; degree = 38; C = 0.0014).

CONCLUSIONS

This integrated analysis will help develop improved therapies and interventions for T1D by identifying novel drug targets.

Nucleotide substitutions in CD101, the human homolog of a diabetes susceptibility gene in non-obese diabetic mouse, in patients with type 1 diabetes

Aims/Introduction

Although genome‐wide association studies have identified more than 50 susceptibility genes for type 1 diabetes, low‐frequency risk variants could remain unrecognized. The present study aimed to identify novel type 1 diabetes susceptibility genes by newly established methods.

Materials and Methods

We carried out whole‐exome sequencing and genome‐wide copy‐number analysis for a Japanese family consisting of two patients with type 1 diabetes and three unaffected relatives. Further mutation screening was carried out for 127 sporadic cases. The functional consequences of identified substitutions were evaluated by in silico analyses and fluorescence‐activated cell sorting of blood samples.

Results

Whole‐exome sequencing and genome‐wide copy‐number analysis of familial cases showed co‐segregation of the p.V863L substitution in CD101, the human homolog of an autoimmune diabetes gene in the non‐obese diabetic mouse, with type 1 diabetes. Mutation screening of CD101 in 127 sporadic cases detected the p.V678L and p.T944R substitutions in two patients. The p.V863L, p.V678L and p.T944R substitutions were absent or extremely rare in the general population, and were assessed as ‘probably/possibly damaging’ by in silico analyses. CD101 expression on monocytes, granulocytes and myeloid dendritic cells of mutation‐positive patients was weaker than that of control individuals.

Conclusions

These results raise the possibility that CD101 is a susceptibility gene for type 1 diabetes.

Mucosal Interactions between Genetics, Diet, and Microbiome in Inflammatory Bowel Disease

Numerous reviews have discussed gut microbiota composition changes during inflammatory bowel diseases (IBD), particularly Crohn’s disease (CD). However, most studies address the observed effects by focusing on studying the univariate connection between disease and dietary-induced alterations to gut microbiota composition. The possibility that these effects may reflect a number of other interconnected (i.e., pantropic) mechanisms, activated in parallel, particularly concerning various bacterial metabolites, is in the process of being elucidated. Progress seems, however, hampered by various difficult-to-study factors interacting at the mucosal level. Here, we highlight some of such factors that merit consideration, namely: (1) the contribution of host genetics and diet in altering gut microbiome, and in turn, the crosstalk among secondary metabolic pathways; (2) the interdependence between the amount of dietary fat, the fatty acid composition, the effects of timing and route of administration on gut microbiota community, and the impact of microbiota-derived fatty acids; (3) the effect of diet on bile acid composition, and the modulator role of bile acids on the gut microbiota; (4) the impact of endogenous and exogenous intestinal micronutrients and metabolites; and (5) the need to consider food associated toxins and chemicals, which can introduce confounding immune modulating elements (e.g., antioxidant and phytochemicals in oils and proteins). These concepts, which are not mutually exclusive, are herein illustrated paying special emphasis on physiologically inter-related processes.

Pancreatitis in hand-foot-and-mouth disease caused by enterovirus 71

Some viruses, including certain members of the enterovirus genus, have been reported to cause pancreatitis, especially Coxsackie virus. However, no case of human enterovirus 71 (EV71) associated with pancreatitis has been reported so far. We here report a case of EV71-induced hand-foot-and-mouth disease (HFMD) presenting with pancreatitis in a 2-year-old girl. This is the first report of a patient with acute pancreatitis in HFMD caused by EV71. We treated the patient conservatively with nasogastric suction, intravenous fluid and antivirals. The patient’s symptoms improved after 8 d, and recovered without complications. We conclude that EV71 can cause acute pancreatitis in HFMD, which should be considered in differential diagnosis, especially in cases of idiopathic pancreatitis.

Innate Immunity Evasion by Enteroviruses: Insights into Virus-Host Interaction

Enterovirus genus includes multiple important human pathogens, such as poliovirus, coxsackievirus, enterovirus (EV) A71, EV-D68 and rhinovirus. Infection with EVs can cause numerous clinical conditions including poliomyelitis, meningitis and encephalitis, hand-foot-and-mouth disease, acute flaccid paralysis, diarrhea, myocarditis and respiratory illness. EVs, which are positive-sense single-stranded RNA viruses, trigger activation of the host antiviral innate immune responses through pathogen recognition receptors such as retinoic acid-inducible gene (RIG-I)-likeand Toll-like receptors. In turn, EVs have developed sophisticated strategies to evade host antiviral responses. In this review, we discuss the interplay between the host innate immune responses and EV infection, with a primary focus on host immune detection and protection against EV infection and viral strategies to evade these antiviral immune responses.

Genetic variations in the PSMA3, PSMA6 and PSMC6 genes are associated with type 1 diabetes in Latvians and with expression level of number of UPS-related and T1DM-susceptible genes in HapMap individuals

The ubiquitin-proteasome system (UPS), a key player of proteostasis network in the body, was implicated in type 1 diabetes mellitus (T1DM) pathogenesis. Polymorphisms in genes encoding proteasome subunits may potentially affect system efficiency. However, data in this field are still limited. To fulfil this gap, single nucleotide polymorphisms in the PSMB5 (rs11543947), PSMA6 (rs2277460, rs1048990), PSMC6 (rs2295826, rs2295827) and PSMA3 (rs2348071) genes were genotyped on susceptibility to T1DM in Latvians. The rs11543947 was found to be neutral and other loci manifested disease susceptibility, with rs1048990 and rs2348071 being the most significantly associated (P < 0.001; OR 2.042 [1.376-3.032] and OR 2.096 [1.415-3.107], respectively). Risk effect was associated with female phenotype for rs2277460 and family history for rs2277460, rs2295826 and rs2295827. Five-locus genotypes being at risk simultaneously at any two or more loci showed strong (P < 0.0001) T1DM association. The T1DM protective effects (P < 0.001) were shown for five-locus genotype and haplotype homozygous on common alleles and composed of common alleles, respectively. Using SNPexp data set, correlations have been revealed between the rs1048990, rs2295826, rs2295827 and rs2348071 T1DM risk genotypes and expression levels of 14 genes related to the UPS and 42 T1DM-susceptible genes encoding proteins involved in innate and adaptive immunity, antiviral response, insulin signalling, glucose-energy metabolism and other pathways implicated in T1DM pathogenesis. Genotype-phenotype and genotype-genotype clusterings support genotyping results. Our results provide evidence on new T1DM-susceptible loci in the PSMA3, PSMA6 and PSMC6 proteasome genes and give a new insight into the T1DM pathogenesis.