Ten metabolites-based algorithm predicts the future development of type 2 diabetes in Chinese

INTRODUCTION

Type 2 diabetes (T2D) is a heterogeneous metabolic disease with large variations in the relative contributions of insulin resistance and β-cell dysfunction across different glucose tolerance subgroups and ethnicities. A more precise yet feasible approach to categorize risk preceding T2D onset is urgently needed. This study aimed to identify potential metabolic biomarkers that could contribute to the development of T2D and investigate whether their impact on T2D is mediated through insulin resistance and β-cell dysfunction.

METHODS

A non-targeted metabolomic analysis was performed in plasma samples of 196 incident T2D cases and 196 age- and sex-matched non-T2D controls recruited from a long-term prospective Chinese community-based cohort with a follow-up period of ∼ 16 years.

RESULTS

Metabolic profiles revealed profound perturbation of metabolomes before T2D onset. Overall metabolic shifts were strongly associated with insulin resistance rather than β-cell dysfunction. In addition, 188 out of the 578 annotated metabolites were associated with insulin resistance. Bi-directional mediation analysis revealed putative causal relationships among the metabolites, insulin resistance and T2D risk. We built a machine-learning based prediction model, integrating the conventional clinical risk factors (age, BMI, TyG index and 2hG) and 10 metabolites (acetyl-tryptophan, kynurenine, γ-glutamyl-phenylalanine, DG(18:2/22:6), DG(38:7), LPI(18:2), LPC(P-16:0), LPC(P-18:1), LPC(P-20:0) and LPE(P-20:0)) (AUROC = 0.894, 5.6% improvement comparing to the conventional clinical risk model), that successfully predicts the development of T2D.

CONCLUSIONS

Our findings support the notion that the metabolic changes resulting from insulin resistance, rather than β-cell dysfunction, are the primary drivers of T2D in Chinese adults. Metabolomes as a valuable phenotype hold potential clinical utility in the prediction of T2D.

Specific triacylglycerol, diacylglycerol, and lyso-phosphatidylcholine species for the prediction of type 2 diabetes: a ~ 16-year prospective study in Chinese

Background

Bioactive lipids play an important role in insulin secretion and sensitivity, contributing to the pathophysiology of type 2 diabetes (T2D). This study aimed to identify novel lipid species associated with incident T2D in a nested case–control study within a long-term prospective Chinese community-based cohort with a median follow-up of ~ 16 years.

Methods

Plasma samples from 196 incident T2D cases and 196 age- and sex-matched non-T2D controls recruited from the Hong Kong Cardiovascular Risk Factor Prevalence Study (CRISPS) were first analyzed using untargeted lipidomics. Potential predictive lipid species selected by the Boruta analysis were then verified by targeted lipidomics. The associations between these lipid species and incident T2D were assessed. Effects of novel lipid species on insulin secretion in mouse islets were investigated.

Results

Boruta analysis identified 16 potential lipid species. After adjustment for body mass index (BMI), triacylglycerol/high-density lipoprotein (TG/HDL) ratio and the presence of prediabetes, triacylglycerol (TG) 12:0_18:2_22:6, TG 16:0_11:1_18:2, TG 49:0, TG 51:1 and diacylglycerol (DG) 18:2_22:6 were independently associated with increased T2D risk, whereas lyso-phosphatidylcholine (LPC) O-16:0, LPC P-16:0, LPC O-18:0 and LPC 18:1 were independently associated with decreased T2D risk. Addition of the identified lipid species to the clinical prediction model, comprised of BMI, TG/HDL ratio and the presence of prediabetes, achieved a 3.8% improvement in the area under the receiver operating characteristics curve (AUROC) (p = 0.0026). Further functional study revealed that, LPC O-16:0 and LPC O-18:0 significantly potentiated glucose induced insulin secretion (GSIS) in a dose-dependent manner, whereas neither DG 18:2_22:6 nor TG 12:0_18:2_22:6 had any effect on GSIS.

Conclusions

Addition of the lipid species substantially improved the prediction of T2D beyond the model based on clinical risk factors. Decreased levels of LPC O-16:0 and LPC O-18:0 may contribute to the development of T2D via reduced insulin secretion.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01677-4.

Factors associated with high compliance behaviour against COVID-19 in the early phase of pandemic: a cross-sectional study in 12 Asian countries

INTRODUCTION

Regardless of having effective vaccines against COVID-19, containment measures such as enhanced physical distancing and good practice of personal hygiene remain the mainstay of controlling the COVID-19 pandemic. Countries across Asia have imposed these containment measures to varying extents. However, residents in different countries would have a differing degree of compliance to these containment measures potentially due to differences in the level of awareness and motivation in the early phase of pandemic.

OBJECTIVES

In our study, we aimed to describe and correlate the level of knowledge and attitude with the level of compliance with personal hygiene and physical distancing practices among Asian countries in the early phase of pandemic.

METHODS

A multinational cross-sectional study was carried out using electronic surveys between May and June 2020 across 14 geographical areas. Subjects aged 21 years and above were invited to participate through social media, word of mouth and electronic mail.

RESULTS

Among the 2574 responses obtained, 762 (29.6%) participants were from East Asia and 1812 (70.4%) were from Southeast Asia (SEA). A greater proportion of participants from SEA will practise physical distancing as long as it takes (72.8% vs 60.6%). Having safe distancing practices such as standing more than 1 or 2 m apart (AdjOR 5.09 95% CI (1.08 to 24.01)) or more than 3 or 4 m apart (AdjOR 7.05 95% CI (1.32 to 37.67)), wearing a mask when they had influenza-like symptoms before the COVID-19 pandemic, preferring online news channels such as online news websites/applications (AdjOR 1.73 95% CI (1.21 to 2.49)) and social media (AdjOR 1.68 95% CI (1.13 to 2.50) as sources of obtaining information about COVID-19 and high psychological well-being (AdjOR 1.39 95% CI (1.04 to 1.87)) were independent factors associated with high compliance.

CONCLUSIONS

We found factors associated with high compliance behaviour against COVID-19 in the early phase of pandemic and it will be useful to consider them in risk assessment, communication and pandemic preparedness.

Impact of the coronavirus disease 2019 pandemic on irritable bowel syndrome

BACKGROUND AND AIM

Gastrointestinal manifestations of the coronavirus disease 2019 (COVID-19) pandemic may mimic irritable bowel syndrome (IBS), and social distancing measures may affect IBS patients negatively. We aimed to study the impact of COVID-19 on respondents with self-reported IBS.

METHODS

We conducted an anonymized survey from May to June 2020 in 33 countries. Knowledge, attitudes, and practices on personal hygiene and social distancing as well as psychological impact of COVID-19 were assessed. Statistical analysis was performed to determine differences in well-being and compliance to social distancing measures between respondents with and without self-reported IBS. Factors associated with improvement or worsening of IBS symptoms were evaluated.

RESULTS

Out of 2704 respondents, 2024 (74.9%) did not have IBS, 305 (11.3%) had self-reported IBS, and 374 (13.8%) did not know what IBS was. Self-reported IBS respondents reported significantly worse emotional, social, and psychological well-being compared with non-IBS respondents and were less compliant to social distancing measures (28.2% vs 35.3%, P = 0.029); 61.6% reported no change, 26.6% reported improvement, and 11.8% reported worsening IBS symptoms. Higher proportion of respondents with no change in IBS symptoms were willing to practice social distancing indefinitely versus those who deteriorated (74.9% vs 51.4%, P = 0.016). In multivariate analysis, willingness to continue social distancing for another 2-3 weeks (vs longer period) was significantly associated with higher odds of worsening IBS.

CONCLUSION

Our study showed that self-reported IBS respondents had worse well-being and compliance to social distancing measures than non-IBS respondents. Future research will focus on occupational stress and dietary changes during COVID-19 that may influence IBS.

Association between well-being and compliance with COVID-19 preventive measures by healthcare professionals: A cross-sectional study

IMPORTANCE

Knowledge and attitude influence compliance and individuals' practices. The risk and protective factors associated with high compliance to these preventive measures are critical to enhancing pandemic preparedness.

OBJECTIVE

This survey aims to assess differences in mental health, knowledge, attitudes, and practices (KAP) of preventive measures for COVID-19 amongst healthcare professionals (HCP) and non-healthcare professionals.

DESIGN

Multi-national cross-sectional study was carried out using electronic surveys between May-June 2020.

SETTING

Multi-national survey was distributed across 36 countries through social media, word-of-mouth, and electronic mail.

PARTICIPANTS

Participants ≥21 years working in healthcare and non-healthcare related professions.

MAIN OUTCOME

Risk factors determining the difference in KAP towards personal hygiene and social distancing measures during COVID-19 amongst HCP and non-HCP.

RESULTS

HCP were significantly more knowledgeable on personal hygiene (AdjOR 1.45, 95% CI -1.14 to 1.83) and social distancing (AdjOR 1.31, 95% CI -1.06 to 1.61) compared to non-HCP. They were more likely to have a positive attitude towards personal hygiene and 1.5 times more willing to participate in the contact tracing app. There was high compliance towards personal hygiene and social distancing measures amongst HCP. HCP with high compliance were 1.8 times more likely to flourish and more likely to have a high sense of emotional (AdjOR 1.94, 95% CI (1.44 to 2.61), social (AdjOR 2.07, 95% CI -1.55 to 2.78), and psychological (AdjOR 2.13, 95% CI (1.59-2.85) well-being.

CONCLUSION AND RELEVANCE

While healthcare professionals were more knowledgeable, had more positive attitudes, their higher sense of total well-being was seen to be more critical to enhance compliance. Therefore, focusing on the well-being of the general population would help to enhance their compliance towards the preventive measures for COVID-19.

A symptom severity questionnaire for patients suffering from functional gastrointestinal disorder: FGI-Checklist

BACKGROUND AND AIM

A well-validated, comprehensive checklist of functional gastrointestinal (FGI) disorder (FGID) symptom severity for tracking symptom profile changes over time is lacking. We aim to develop and validate a comprehensive symptom severity checklist for FGID.

METHODS

A 20-item scale, including both upper and lower gastrointestinal symptoms, was generated to measure the symptom severity commonly found in FGID. Patients who experienced at least monthly symptoms of FGID with negative endoscopy findings were invited to complete the FGI-Checklist, Patient Health Questionaire-9 for assessing depressive symptoms, and Patient Health Questionnaire-15 for assessing somatic symptoms at baseline. A subset of patients who met Rome III diagnostic criteria of gastroesophageal reflux disease, functional dyspepsia, and irritable bowel syndrome received medication treatment for 8-12 weeks and completed the FGI-Checklist again at a follow-up visit. Exploratory factor analysis was performed for subscales formation and psychometric properties were measured.

RESULTS

Six hundred and forty-one patients were recruited for current study and 108 (16.8%) of them completed the FGI-Checklist again at follow-up. Exploratory factor analysis identified a five-factor solution accounting for 66.8% of the total variance. The five factors are named esophageal syndrome, reflux syndrome, functional dyspepsia syndrome, nausea and vomiting syndrome, and abdominal and bowel syndrome. The FGI-Checklist total score correlated with Patient Health Questionaire-9 and Patient Health Questionnaire-15 (all P < 0.001), which demonstrated good construct validity. Good item-internal consistency was found (Cronbach's alphas: 0.69-0.87). Responsiveness for reflux syndrome subscale, functional dyspepsia syndrome subscale, and abdominal and bowel syndrome subscale after medication treatment was significant (paired-t-test: all P < 0.01).

CONCLUSION

The instrument, Checklist, is valid and reliable.

Atopic Patients Who Fulfilled Rome III Criteria for Irritable Bowel Syndrome Had Higher Animal Danders Sensitization

Background/Aims

The relationship between animal exposure and irritable bowel syndrome (IBS) is debated. Epidemiological studies have shown that atopy is more prevalent in IBS patients and vice versa. We set out to examine the association between animal danders sensitization and IBS-like symptoms in atopic patients.

Methods

We recruited 69 consecutive atopic patients from the allergy clinic of a tertiary hospital. Subjects completed validated bowel questionnaires, underwent skin prick test, blood was collected for serum total immunoglobulin E, and ImmunoCAP immune solid-phase allergen chip (ISAC) IgE multiplex assay.

Results

Twenty-eight (41.0%) atopic patients fulfilled the Rome III IBS criteria (atopy-IBS). There were no differences in gender, age, pet ownership, total serum IgE, or food allergen sensitization between atopy-IBS group and atopy-non-IBS group. We found that atopy-IBS group had significantly higher number of positive skin prick test for cat dander (64.3% vs 24.4%, P < 0.001), dog dander (64.3% vs 41.5%, P = 0.015) and weed pollens (32.1% vs 14.6%, P = 0.050) compared to atopy-non-IBS group. Out of 112 components from 51 allergen sources (both aeroallergen and food allergens), only Fel d1 (a major cat dander antigen) IgE is significantly higher in atopy-IBS group than atopy-non-IBS group (21.4% vs 2.4%, P = 0.029). Majority of atopy-IBS patients had mixed-type IBS.

Conclusions

We demonstrated an association between animal danders sensitization, in particular cat dander sensitization, and IBS-like symptoms in atopic patients. Future studies are needed to explore the relationship between aeroallergen and functional gastrointestinal disorders. Sensitization may be related to the pathophysiology of IBS or it could be that we are missing aeroallergen-induced gut allergy.

Gut Microbiome Fermentation Determines the Efficacy of Exercise for Diabetes Prevention

Exercise is an effective strategy for diabetes management but is limited by the phenomenon of exercise resistance (i.e., the lack of or the adverse response to exercise on metabolic health). Here, in 39 medication-naive men with prediabetes, we found that exercise-induced alterations in the gut microbiota correlated closely with improvements in glucose homeostasis and insulin sensitivity (clinicaltrials.gov entry NCT03240978). The microbiome of responders exhibited an enhanced capacity for biosynthesis of short-chain fatty acids and catabolism of branched-chain amino acids, whereas those of non-responders were characterized by increased production of metabolically detrimental compounds. Fecal microbial transplantation from responders, but not non-responders, mimicked the effects of exercise on alleviation of insulin resistance in obese mice. Furthermore, a machine-learning algorithm integrating baseline microbial signatures accurately predicted personalized glycemic response to exercise in an additional 30 subjects. These findings raise the possibility of maximizing the benefits of exercise by targeting the gut microbiota.

Functional dyspepsia susceptibility is associated with TGFB1 gene polymorphisms (RS4803455, RS1800469) in H pylori-negative Chinese population

BACKGROUND

We previously published that altered expression of gastric TRPV1, BDNF, and peripheral cytokines was present in patients with functional dyspepsia. We herein examine whether genetic predisposition in altered biomarkers influences dyspeptic, sleep, and mood symptoms in patients with FD without previous infection.

METHODS

Consecutive adult FD patients (Rome III) with no recent history of gastroenteritis and asymptomatic age- and sex-matched healthy controls were recruited for upper endoscopy. Subjects with GERD and IBS as predominant symptoms, diabetes mellitus, current or previous H pylori infection, psychiatric illness, and recent use of NSAID or PPI were excluded. The genetic associations with dyspeptic symptoms, sleep quality, and mood symptoms were evaluated. Genetic polymorphisms in TRPV1, TGFB1, TNF, COMT, BDNF, IL6, IL8, IL10, and IL12 were analyzed.

KEY RESULTS

Twenty-nine male FD patients and 104 female FD patients were age matched (±3 years) with 81 healthy subjects. All had postprandial distress syndrome (PDS) as predominant subtype (PDS: 130, EPS: 3). SNPs in TGFB1 showed significant associations in dyspeptic patients after age and sex adjustment [for RS4803455: in the codominant model (C/A, OR = 0.34 (0.18-0.65), P = .004); in the dominant model (genotype C/C vs C/A-A/A, OR = 0.42 (0.23-0.77), P = .004); and in the overdominant model (genotype C/C-A/A vs C/A, OR = 0.38 (0.21-0.70), P < .001)] [for RS1800469: in dominant model (genotype A/A vs A/G-G/G, OR = 0.52 (0.27-0.99), P = .043)]. A allele in RS4803455 was associated with higher HADS depression score (P = .05) and epigastric burning sensation(P = .01).

CONCLUSIONS AND INFERENCES

Our data showed that dyspeptic patients predispose genetic difference in TGFB1 which may influence the severity of dyspepsia.

Vitamin D3 activates the autolysosomal degradation function against Helicobacter pylori through the PDIA3 receptor in gastric epithelial cells

Helicobacter pylori (H. pylori) is a common human pathogenic bacterium. Once infected, it is difficult for the host to clear this organism using the innate immune system. Increased antibiotic resistance further makes it challenging for effective eradication. However, the mechanisms of immune evasion still remain obscure, and novel strategies should be developed to efficiently eliminate H. pylori infection in stomachs. Here we uncovered desirable anti-H. pylori effect of vitamin D3 both in vitro and in vivo, even against antibiotic-resistant strains. We showed that H. pylori can invade into the gastric epithelium where they became sequestered and survived in autophagosomes with impaired lysosomal acidification. Vitamin D3 treatment caused a restored lysosomal degradation function by activating the PDIA3 receptor, thereby promoting the nuclear translocation of PDIA3-STAT3 protein complex and the subsequent upregulation of MCOLN3 channels, resulting in an enhanced Ca²⁺ release from lysosomes and normalized lysosomal acidification. The recovered lysosomal degradation function drives H. pylori to be eliminated through the autolysosomal pathway. These findings provide a novel pathogenic mechanism on how H. pylori can survive in the gastric epithelium, and a unique pathway for vitamin D3 to reactivate the autolysosomal degradation function, which is critical for the antibacterial action of vitamin D3 both in cells and in animals, and perhaps further in humans. Abbreviations: 1,25D3: 1α, 25-dihydroxyvitamin D3; ATG5: autophagy related 5; Baf A1: bafilomycin A₁; BECN1: beclin 1; CagA: cytotoxin-associated gene A; CFU: colony-forming unit; ChIP-PCR: chromatin immunoprecipitation-polymerase chain reaction; Con A: concanamycin A; CQ: chloroquine; CRISPR: clustered regularly interspaced short palindromic repeats; CTSD: cathepsin D; GPN: Gly-Phe-β-naphthylamide; H. pylori: Helicobacter pylori; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MCOLN1: mucolipin 1; MCOLN3: mucolipin 3; MCU: mitochondrial calcium uniporter; MOI: multiplicity of infection; NAGLU: N-acetyl-alpha-glucosaminidase; PDIA3: protein disulfide isomerase family A member 3; PMA: phorbol 12-myristate 13-acetate; PRKC: protein kinase C; SQSTM1: sequestosome 1; STAT3: signal transducer and activator of transcription 3; SS1: Sydney Strain 1; TRP: transient receptor potential; VacA: vacuolating cytotoxin; VD3: vitamin D3; VDR: vitamin D receptor.

Fecal microbiota transplantation confers beneficial metabolic effects of diet and exercise on diet-induced obese mice

Diet and exercise are conventional methods for controlling body weight and are linked to alterations in gut microbiota. However, the associations of diet, exercise, and gut microbiota in the control of obesity remain largely unknown. In the present study, using 16S rRNA amplicon sequencing and fecal microbiota transplantation (FMT), normal fat diet (NFD), exercise and their combination resulted in improved metabolic profiles in comparison to sedentary lifestyle with high fat diet (HFD). Moreover, diet exerted more influence than exercise in shaping the gut microbiota. HFD-fed mice receiving FMT from NFD-exercised donors not only showed remarkably reduced food efficacy, but also mitigated metabolic profiles (p < 0.05). The transmissible beneficial effects of FMT were associated with bacterial genera Helicobacter, Odoribacter and AF12 and overrepresentation of oxidative phosphorylation and glycolysis genes. Our findings demonstrate that the beneficial effects of diet and exercise are transmissible via FMT, suggesting a potential therapeutic treatment for obesity.

Up-regulation of transient receptor potential vanilloid (TRPV) and down-regulation of brain-derived neurotrophic factor (BDNF) expression in patients with functional dyspepsia (FD)

BACKGROUND

The role of immune activation in Functional Dyspepsia (FD) patients without previous infection is unclear. We compare the gastric and circulating brain-derived neurotropic factor (BDNF), receptor potential vanilloid type (TRPV) families and various cytokines in FD patients.

METHODS

Consecutive adult FD patients (Rome III) with no recent history of gastroenteritis and asymptomatic healthy controls were recruited for upper endoscopy. Subjects with GERD and IBS as predominant symptoms, diabetes mellitus, current or previous Helicobacter pylori infection, psychiatric illness and recent use of NSAID or PPI were excluded. Corpus biopsies and serum samples were collected.

KEY RESULTS

Forty three [M:F=8:35, mean age: 35.0 (9.3)] FD patients were compared with 23 healthy controls [M:F=8:15, mean age: 36.6 (10.2)]. FD patients had postprandial distress syndrome (PDS) as predominant sub-type (PDS: 36, EPS: 2). There was no significant difference in the median inflammation score (FD:0 (0-1) vs Control:0 (0-1), P=.79). However, FD patients had significantly higher mRNA expression of TRPV1 (FD:0.014±0.007, Control:0.003±0.001, 4.6 fold, P=.02) and TRPV2 (FD:0.012±0.006, Control:0.003±0.001, 4 fold, P=.02) compared to controls. The serum (FD:258.0±12.3 ng ml^-1 , Control:319.7±18.1 ng ml^-1 , P<.01) and gastric BDNF mRNA (FD:0.06±0.008, Control:0.092±0.01, 0.65 fold, P=.02)levels significantly lower in FD patients. Secretion of cytokines (IL-4, IL-5, IL-6, IL-8, IL-10, G-CSF, TGF-β2, MCP-1)was also highly correlated with dyspeptic symptoms in patients with FD.

CONCLUSIONS & INFERENCES

Despite lacking gastric mucosal inflammation, up-regulation of TRPV1 and TRPV2, down-regulation of BDNF were observed in FD patients. These suggest that immune alteration may contribute to the pathogenesis of FD without any previous infection.

Decreased Basal and postprandial plasma serotonin levels in patients with functional dyspepsia

BACKGROUND & AIMS

Patients with diarrhea-predominant irritable bowel syndrome (IBS) have been found to have increased postprandial levels of serotonin (5-HT). Functional dyspepsia (FD) and IBS have been proposed to have common methods of pathogenesis, but little is known about the role of 5-HT in FD.

METHODS

We measured postprandial levels of 5-HT in 54 patients with FD (based on Rome III criteria) and 28 asymptomatic healthy individuals (controls). Patients with gastroesophageal reflux disease and IBS as their predominant symptom were excluded. After an overnight fast, the subjects drank a liquid meal (Ensure; 1.06 kcal/mL at 30 mL/min) and underwent a (13)C-octanoic acid breath test to measure gastric emptying times. Blood samples were collected at 0, 30, 60, 90, and 120 minutes after the liquid meal for the 5-HT assay.

RESULTS

Thirty-five patients with FD (65%) had postprandial distress syndrome, and 6 (11%) had a combination of postprandial distress syndrome and epigastric pain syndrome. There were no differences in rates of gastric emptying between patients with FD (103.6 ± 19.4 minutes) and controls (83.1 ± 4.0 minutes; P = .30). However, patients with FD had lower caloric intake (823.40 ± 44.1 kcal) than controls (1021 ± 68.2 kcal; P = .026). Patients with FD also had lower basal (P = .03) and postprandial plasma levels of serotonin at 30 minutes (P = .04), 60 minutes (P = .01), 90 minutes (P = .02), and 120 minutes (P = .002) than controls, as well as area under the curve values over the 120-minute time period (P = .005). Repeated-measures analysis of variance correlated 5-HT level with FD (P < .001).

CONCLUSIONS

In contrast to patients with diarrhea-predominant IBS, those with FD have decreased basal and postprandial plasma levels of 5-HT. These findings indicate that the pathogenic mechanism of FD differs from that of diarrhea-predominant IBS, and that strategies to alter 5-HT levels or activity might be developed to treat patients with FD.