Identification of causal metabolites related to multiple autoimmune diseases.

Observational studies provide evidence that metabolites may be involved in the development of autoimmune diseases (ADs), but whether it is causal is still unknown. Based on the large-scale genome-wide association studies (GWAS) summary statistics, we performed two-sample Mendelian randomization (MR) to evaluate the causal associations between human blood metabolites and multiple ADs, which were inflammatory bowel disease (IBD), ulcerative colitis (UC), crohns disease (CD), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), type 1 diabetes (T1D), multiple sclerosis (MS), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). After Bonferroni adjustment, we identified 6 causal features of metabolites, i.e., glycerol 2-phosphate for T1D, hexadecanedioate, phenylacetylglutamine and laurylcarnitine for RA, glycine and arachidonate (20:4n6) for CD. Comprehensive sensitive analysis was further performed to validate the robustness of associations. We also observed some overlaps of metabolites among different ADs, implying similar or shared underlying mechanisms in such pathogenic processes. Multivariable MR analysis was then conducted to avoid potential pleiotropic effect of other complex traits. After controlling for several common traits, multivariable MR analysis ruled out most of potential pleiotropic effects and validated independence of identified metabolites. Finally, metabolic pathway analysis was performed based on suggestive metabolites for each AD respectively and a total of seven metabolic pathways were identified. In conclusion, this study provided novel insights into investigating causal role of blood metabolites in development of multiple ADs through a comprehensive genetic pathway.

Shortening Oral Simethicone-to-Colonoscopy Interval Increases Bowel Preparation Quality.

BACKGROUND Simethicone can improve bowel preparation quality, but the optimal timing of oral simethicone before colonoscopy has not been determined. This study aimed to explore the effect of the time interval between oral simethicone and the start of colonoscopy (S-C) on bowel preparation quality. MATERIAL AND METHODS A total of 364 patients undergoing colonoscopy at our department from August 1, 2021 to November 30, 2021 were included in the training cohort, and 420 consecutive patients from December 15, 2021 to January 31, 2022 comprised the validation cohort. They were classified into short and long S-C groups according to the median S-C. Bowel preparation quality evaluated by the Boston Bowel Preparation Scale was compared between the 2 groups. Logistic regression analyses were performed to explore the correlation between S-C and bowel preparation quality, and we explored the effect of run-way time and time of starting colonoscopy on bowel preparation quality. RESULTS In the training cohort, 182 and 182 patients were classified into the short and long S-C groups, respectively; in the validation cohort, 210 and 210 patients were classified into the 2 groups, respectively. In the 2 cohorts, the short S-C group had a significantly higher rate of adequate/excellent bowel preparation than the long S-C group. Logistic regression analyses showed that shorter S-C, shorter run-way time, and colonoscopy in the morning were all correlated with adequate/excellent bowel preparation. CONCLUSIONS Bowel preparation quality may be affected by S-C, run-way time, and time of starting colonoscopy. S-C shortening should be given equal importance as run-way time shortening.

Effect of Body Mass Index on Cecal Intubation Time During Unsedated Colonoscopy: Variation Across the Learning Stages of an Endoscopist.

BACKGROUND Body mass index (BMI) and endoscopists' experiences can be associated with cecal intubation time (CIT), but such associations are controversial. This study aimed to clarify the association between BMI and CIT during unsedated colonoscopy at 3 learning stages of a single endoscopist. MATERIAL AND METHODS A total of 1500 consecutive patients undergoing unsedated colonoscopy by 1 endoscopist at our department from December 11, 2020, to August 21, 2022, were reviewed. They were divided into 3 learning stages according to the number of colonoscopies performed by 1 endoscopist, including intermediate (501-1000 colonoscopies), experienced (1001-1500 colonoscopies), and senior stages (1501-2000 colonoscopies). Variables that significantly correlated with CIT were identified by Spearman rank correlation analyses and then included in multiple linear regression analysis. RESULTS Overall, 1233 patients were included. Among them, 392, 420, and 421 patients were divided into intermediate, experienced, and senior stages, respectively. Median CIT was 7.83, 6.38, and 5.58 min at intermediate, experienced, and senior stages, respectively (P.

Rheumatoid arthritis and osteoporosis: shared genetic effect, pleiotropy and causality.

Rheumatoid arthritis (RA) is associated with increased localized and generalized bone loss, but the complex genetic mechanism between them is still unknown. By leveraging large-scale genome-wide association studies summary statistics and individual-level datasets (i.e. UK Biobank), a series of genetic approaches were conducted. Linkage disequilibrium score regression reveals a shared genetic correlation between RA and estimated bone mineral density (eBMD) (rg = -0.059, P = 0.005). The PLACO analysis has identified 74 lead (8 novel) pleiotropic loci that could be mapped to 99 genes, the genetic functions of which reveal the possible mechanism underlying RA and osteoporosis. In European, genetic risk score (GRS) and comprehensive Mendelian randomization (MR) were utilized to evaluate the causal association between RA and osteoporosis in European and Asian. The increase in GRS of RA could lead to a decrease of eBMD (beta = -0.008, P = 3.77E-6) and a higher risk of facture [odds ratio (OR) = 1.012, P = 0.044]. MR analysis identified that genetically determined RA was causally associated with eBMD (beta = -0.021, P = 4.14E-05) and fracture risk (OR = 1.036, P = 0.004). Similar results were also observed in Asian that osteoporosis risk could be causally increased by RA (OR = 1.130, P = 1.04E-03) as well as antibodies against citrullinated proteins-positive RA (OR = 1.083, P = 0.015). Overall, our study reveals complex genetic mechanism between RA and osteoporosis and provides strong evidence for crucial role of RA in pathogenesis of osteoporosis.

A novel long non-coding RNA, lnc-RNU12, influences the T-cell cycle via c-JUN and CCNL2 in rheumatoid arthritis.

OBJECTIVES: Long non-coding RNAs (lncRNAs) play important roles in RA pathogenesis. However, specific lncRNAs that regulate gene expression in RA pathogenesis are poorly known. This study was undertaken to characterize a novel lncRNA (lnc-RNU12) that has a lower-than-normal expression level in RA patients. METHODS: We performed initial genome-wide lncRNA microarray screening in peripheral blood mononuclear cells from 28 RA cases and 18 controls. Multiple methods were used to validate the detected associations between lncRNAs and RA. Furthermore, we identified the source and characteristics of the highlighted lncRNAs, detected the target genes, and determined the functional effect on immune cells through lncRNA knock-down in Jurkat T cell lines. RESULTS: lnc-RNU12 was downregulated in peripheral blood mononuclear cells and T cell subtypes of RA patients and was genetically associated with RA risk. lnc-RNU12 mediates the effect of microbiome alterations on RA risk. Activation of T cells caused low expression of lnc-RNU12. Knock-down of lnc-RNU12 in Jurkat T cells caused cell cycle S-phase arrest and altered the expression of protein-coding genes related to the cell cycle and apoptosis (e.g. c-JUN, CCNL2, CDK6, MYC, RNF40, PKM, VPS35, DNAJB6 and FLCN). Finally, c-JUN and CCNL2 were identified as target genes of lnc-RNU12 at the mRNA and protein expression levels. RNA-binding protein immunoprecipitation assays verified the interaction between lnc-RNU12 and the two proteins (c-Jun and cyclin L2) in Jurkat cells. CONCLUSIONS: Our study suggested that lnc-RNU12 was involved in the pathogenesis of RA by influencing the T cell cycle by targeting c-JUN and CCNL2.

Establishment of reference intervals for bone turnover markers in healthy Chinese older adults.

BACKGROUND: Reference ranges for bone turnover markers (BTMs) are still lacking in the healthy Chinese population. AIM: To establish reference intervals for BTMs and to investigate the correlations between BTMs and bone mineral density (BMD) in Chinese older adults. SUBJECTS AND METHODS: A community-based cross-sectional study was conducted among 2511 Chinese subjects aged over 50 yrs residing in Zhenjiang, Southeast China. Reference intervals for BTMs (i.e. procollagen type I N-terminal propeptide, P1NP; ß cross-linked C-terminal telopeptide of type I collagen, ß-CTX) were calculated as the central 95% range of all measurements in Chinese older adults. RESULTS: The reference intervals of P1NP, ß-CTX and P1NP/ß-CTX were 15.8-119.9 ng/mL, 0.041-0.675 ng/mL and 49.9-1261.5 for females and 13.6-111.4 ng/mL, 0.038-0.627 ng/mL and 41.0-1269.1 for males, respectively. In the multiple linear regression analysis, only ß-CTX was negatively associated with BMD after adjusting for age and body mass index (BMI) in both sex-stratified groups (all p < .05). CONCLUSION: This study established age- and sex-specific reference intervals for BTMs in a large sample of healthy Chinese participants ≥ 50 and < 80 years of age and explored the correlations between BTMs and BMD, which provides an effective reference for the assessment of bone turnover in the clinical practice of osteoporosis.

Body Surface Area (BSA) is a Better Osteoporosis Associated Anthropometric Parameter Than Other Anthropometric Parameters in Elderly Population.

Body surface area (BSA) is widely used for adjusting drug dose, while few studies have yet systematically evaluated its association with osteoporosis and compared its advantage with other anthropometric parameters in osteoporotic risk prediction. A total of 10,021 Chinese individuals aged over 65 years were enrolled in our study. Bone mineral density (BMD) was measured, and demographic information was also collected. Pearson correlation analysis, receiver operating characteristic (ROC) curves and predictive analysis were performed to assess the clinical practice of BSA for osteoporosis. BSA had the strongest correlation with BMD (0.544, p < 0.001) compared with conventional anthropometric indices. Besides, BSA had the highest power in osteoporosis prediction, with an area under the curve (AUC) reaching 0.81. After incorporating BSA into the osteoporosis risk prediction model, the AUC improved from 0.82 to 0.83 (p < 0.01). We found BSA provided additional diagnostic value beyond conventional anthropometric information with continuous and category NRIs were 30.40% (p < 0.01) and 3.29% (p < 0.01), respectively, and the IDI was 1.85% (p < 0.01). BSA was positively associated with osteoporosis and showed superior discriminative ability for osteoporosis risk prediction compared with other anthropometric parameters in the Chinese elderly population.

The effect of a body shape index (ABSI) and its interaction with low estimated glomerular filtration rate (eGFR) on osteoporosis in elderly Chinese.

BACKGROUND: Both obesity and chronic kidney disease (CKD) contribute to osteoporosis risk, but the effect of a newly developed index (e.g., a body shape index, ABSI) of central obesity and its interaction with low estimated glomerular filtration rate (eGFR) on osteoporosis remains unknown. METHODS: A total of 2534 Chinese individuals were enrolled in our ongoing cohort study: Osteoporosis Preventive Project. ABSI and eGFR were calculated as obesity-related indexes and renal function markers, respectively. A logistic regression model was used to estimate the association between osteoporosis and related clinical parameters (e.g., ABSI, eGFR), and to assess the additive and multiplicative interactions between risk factors and osteoporosis. Relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (SI) were calculated to assess the additive interaction. RESULTS: High ABSI was significantly associated with an increased risk of osteoporosis in participants compared with the lowest quartile of ABSI in both crude and adjusted models. Individuals in the lower quartiles of eGFR had a significantly increased risk of osteoporosis compared with those in the highest quartiles in crude models. After adding age and other variables in the model, the association was abolished. In addition, after adjusting for variables, high ABSI with low eGFR (RERI: 0.45, 95% CI: 0.15-0.75; AP: 0.39, 95% CI: 0.17-0.60) still displayed a noticeable interaction on the risk of osteoporosis. The multiplicative interactive effect between high ABSI with low eGFR on osteoporosis was statistically significant in the multivariable-adjusted model (P < 0.05). CONCLUSION: Our study indicated that higher ABSI increases the risk of osteoporosis independently and synergistically with low eGFR in Chinese elderly adults. The findings increase our understanding of the interactions of osteoporosis risk factors and may help provide potential interventions for osteoporosis.

Novel microbiota-related gene set enrichment analysis identified osteoporosis associated gut microbiota from autoimmune diseases.

INTRODUCTION: Gut microbiota is now considered to be a hidden organ that interacts bidirectionally with cellular responses in numerous organs belonged to the immune, bone, and nervous systems. Here, we aimed to investigate the relationships between gut microbiota and complex diseases by utilizing multiple publicly available genome-wide association. MATERIALS AND METHODS: We applied a novel microbiota-related gene set enrichment analysis approach to detect the associations between gut microbiota and complex diseases by processing genome-wide association studies (GWASs) data sets of six autoimmune diseases (including celiac disease (CeD), inflammatory bowel diseases (IBD), multiple sclerosis (MS), primary biliary cirrhosis (PBC), type 1 diabetes (T1D) and primary sclerosing cholangitis (PSC)) and osteoporosis (OP). RESULTS: The family Oxalobacteraceae and genus Candidatus_Soleaferrea were found to be correlated with all of the six autoimmune diseases (FDR adjusted P < 0.05). Moreover, we observed that the six autoimmune diseases except PBC shared 3 overlapping features (including family Peptostreptococcaceae, order Gastranaerophilales and genus Romboutsia). For all of the six autoimmune diseases and BMDs (LS-BMD and TB-BMD), an association signal was observed for genus Candidatus_Soleaferrea (FDR adjusted P < 0.05). Notably, FA / FN-BMD shared the maximum number of overlapping microbial features (e.g., genus Ruminococcaceae_UCG009, Erysipelatoclostridium and Ruminococcaceae_UCG013). CONCLUSION: Our study found that part of the gut microbiota could be novel regulators of BMDs and autoimmune diseases via the effects of its metabolites and may lead to a better understanding of the role played by gut microbiota in the communication of the microbiota-skeletal/immune-gut axis.

Identification of Potential Pleiotropic Genes for Immune and Skeletal Diseases Using Multivariate MetaCCA Analysis.

Background: Immune and skeletal systems physiologically and pathologically interact with each other. Immune and skeletal diseases may share potential pleiotropic genetics factors, but the shared specific genes are largely unknown. Objective: This study aimed to investigate the overlapping genetic factors between multiple diseases (including rheumatoid arthritis (RA), psoriasis, osteoporosis, osteoarthritis, sarcopenia, and fracture). Methods: The canonical correlation analysis (metaCCA) approach was used to identify the shared genes for six diseases by integrating genome-wide association study (GWAS)-derived summary statistics. The versatile Gene-based Association Study (VEGAS2) method was further applied to refine and validate the putative pleiotropic genes identified by metaCCA. Results: About 157 (p<8.19E-6), 319 (p<3.90E-6), and 77 (p<9.72E-6) potential pleiotropic genes were identified shared by two immune diseases, four skeletal diseases, and all of the six diseases, respectively. The top three significant putative pleiotropic genes shared by both immune and skeletal diseases, including HLA-B, TSBP1, and TSBP1-AS1 (p

Global Public Interests and Dynamic Trends in Osteoporosis From 2004 to 2019: Infodemiology Study.

BACKGROUND: With the prolonging of human life expectancy and subsequent population aging, osteoporosis (OP) has become an important public health issue. OBJECTIVE: This study aimed to understand the global public search interests and dynamic trends in "osteoporosis" using the data derived from Google Trends. METHODS: An online search was performed using the term "osteoporosis" in Google Trends from January 1, 2004, to December 31, 2019, under the category "Health." Cosinor analysis was used to test the seasonality of relative search volume (RSV) for "osteoporosis." An analysis was conducted to investigate the public search topic rising in RSV for "osteoporosis." RESULTS: There was a descending trend of global RSV for "osteoporosis" from January 2004 to December 2014, and a slowly increasing trend from January 2015 to December 2019. Cosinor analysis showed significant seasonal variations in global RSV for "osteoporosis" (P=.01), with a peak in March and a trough in September. In addition, similar decreasing trends of RSV for "osteoporosis" were found in Australia, New Zealand, Ireland, and Canada from January 2004 to December 2019. Cosinor test revealed significant seasonal variations in RSV for "osteoporosis" in Australia, New Zealand, Canada, Ireland, UK, and USA (all P<.001). Furthermore, public search rising topics related to "osteoporosis" included denosumab, fracture risk assessment tool, bone density, osteopenia, osteoarthritis, and risk factor. CONCLUSIONS: Our study provided evidence about the public search interest and dynamic trends in OP using web-based data, which would be helpful for public health and policy making.

Prevalence and genotype distribution of human papillomavirus infection among women: A population-based study in Dali Bai Autonomous Prefecture, Yunnan Province, China.

Accumulating evidence indicates that persistent infection with high-risk oncogenic human papillomavirus (HPV) genotypes is the most important risk factor for cervical cancer, and that the distribution of HPV genotypes varies regionally. This study explored the prevalence and genotype distribution of HPV infection among Han, Yi, and Bai women in various regions of Dali Bai Autonomous Prefecture, Yunnan Province, China. This cross-sectional study included 2779 women (20-76 years old) who were referred for 21-HPV genotype array diagnostic from five regions of Dali Bai Autonomous Prefecture between February 2013 and May 2016. Statistical methods used included a the χ2 test, Fisher's exact test, t test, and logistic regression. Overall HPV prevalence in the study population was 7.6%. HPV-52, HPV-58, HPV-18, HPV-81, and HPV-16 were the most prevalent genotypes in the study area, and notably, the prevalence of HPV-58 was significantly higher among women in Heqing County than that in other regions. Univariate analysis showed that husband's age, region, fertility status, and parity were potential factors associated with HPV infection. Multivariate logistic regression analysis revealed that Heqing County was an independent risk factor for HPV infection among women in the Dali area, moreover, Yi women showed the highest risk for HPV infections. Overall, our finding emphasizing the urgent need for an HPV screening and prevention program in Heqing County and Yi women. We also suggest that HPV-related health education should be provided not only to women, but also to men, to reduce the risk of infection in women.

A Biomass-Derived Carbon-Based Electrocatalyst for Efficient N2 Fixation to NH3 under Ambient Conditions.

Currently, NH3 production primarily depends on the Haber-Bosch process, which operates at elevated temperatures and pressures and leads to serious CO2 emissions. Electrocatalytic N2 reduction offers an environmentally benign approach for the sustainable synthesis of NH3 under ambient conditions. This work reports the development of biomass-derived amorphous oxygen-doped carbon nanosheet (O-CN) using tannin as the precursor. As a metal-free electrocatalyst for N2 -to-NH3 conversion, such O-CN shows high catalytic performances, achieving a large NH3 yield of 20.15 µg h-1 mg-1 cat. and a high Faradic efficiency of 4.97 % at -0.6 V vs. reversible hydrogen electrode (RHE) in 0.1 m HCl at ambient conditions. Remarkably, it also exhibits high electrochemical selectivity and durability.

A MoN nanosheet array supported on carbon cloth as an efficient electrochemical sensor for nitrite detection.

Nitrite, widely found in the environment and the food industry, poses a great threat to human health because of its potential toxicity, and its detection is highly important. We report that a MoN nanosheet array on carbon cloth (MoN NA/CC) behaves as an efficient catalyst for nitrite reduction in neutral solution. As a nitrite sensor, this MoN NA/CC offers a wide linear range from 1 µM to 5 mM and a low detection limit of 3 nM (S/N = 3), with a high sensitivity of 4319 µA mM-1 cm-2 and long-term stability and reproducibility.

Excellent Bowel Preparation Quality Is Not Superior to Good Bowel Preparation Quality for Improving Adenoma/Polyp Detection Rate.

Background: Adequate bowel preparation quality is essential for high-quality colonoscopy according to the current guidelines. However, the excellent effect of bowel preparation on adenoma/polyp detection rate (ADR/PDR) remained controversial. Methods: During the period from December 2020 to August 2022, a total of 1566 consecutive patients underwent colonoscopy by an endoscopist. Their medical records were reviewed. According to the Boston bowel preparation scale, patients were divided into excellent, good, and poor bowel preparation quality groups. ADR/PDR, diminutive ADR/PDR, small ADR/PDR, intermediate ADR/PDR, large ADR/PDR, and number of adenomas/polyps were compared among them. Logistic regression analyses were performed to identify the factors that were significantly associated with ADR/PDR. Results: Overall, 1232 patients were included, of whom 463, 636, and 133 were assigned to the excellent, good, and poor groups, respectively. The good group had a significantly higher ADR/PDR (63% vs 55%, P = .015) and a larger number of adenomas/polyps (2.5 ± 3.2 vs 2.0 ± 2.8, P = .030) than the poor group. Both ADR/PDR (63% vs 55%, P = .097) and number of adenomas/polyps (2.2 ± 2.8 vs 2.0 ± 2.8, P = .219) were not significantly different between excellent and poor groups. The excellent (9% vs 4%, P = .045) and good (9% vs 4%, P = .040) groups had a significantly higher intermediate ADR/PDR than the poor group. Logistic regression analyses showed that either good (odds ratio [OR] = 1.786, 95% CI = 1.046-3.047, P = .034) or excellent (OR = 2.179, 95% CI = 1.241-3.826, P = .007) bowel preparation quality was independently associated with a higher ADR/PDR compared with poor bowel preparation quality. Excellent (OR = 1.202, 95% CI = 0.848-1.704, P = .302) bowel preparation quality was not independently associated with a higher ADR/PDR compared with good bowel preparation quality. Conclusions: The pursuit of excellence in bowel preparation does not show an association with increased ADR/PDR and number of adenomas/polyps compared with a good level. In addition, our study further contributes to the existing evidence that poor bowel preparation compromises ADR/PDR and number of adenomas/polyps.

Integration of protein L-immobilized epoxy magnetic bead capture with LC-MS/MS for therapeutic monoclonal antibody quantification in serum.

In recent years, there has been a growing interest in the thriving monoclonal antibody (mAb) industry due to the wide utilization of mAbs in clinical therapies. Robust and accurate bioanalytical methods are required to enable fast quantification of mAbs in biological matrices, especially in the context of pharmacokinetics (PKs)/pharmacodynamics (PDs) and therapeutic drug monitoring (TDM) studies. In this investigation, we presented a novel immuno-magnetic capture coupled with a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method designed for the quantification of immunoglobulin G-kappa-based mAbs in biological fluids. The immunoaffinity absorbent for mAb drug purification was meticulously crafted by immobilizing protein L onto monosize, magnetic poly(glycidyl methacrylate) (m-pGMA) beads, synthesized through dispersion polymerization. The microspheres were acquired with an average size of 1.6 µm, and the optimal binding of mAbs from the aqueous mAb solution was determined to be 45.82 mg g-1. The quantification of mAbs in 10 µL serum samples was achieved through affinity purification using m-pGMA@protein L beads (employing rituximab as an internal standard (IS)), on-bead reduction, and rapid tryptic digestion. Remarkably, the entire process, taking less than 2.5 hours, held significant potential for simplifying pretreatment procedures and minimizing analytical time. Furthermore, the developed method underwent validation in accordance with the European Medicines Agency (EMA) guidelines. The assay demonstrated commendable linearity within the 2-400 µg mL-1 range for both daratumumab and pembrolizumab. Intra- and inter-assay coefficients of variation fell within the range of 0.7% to 13.4%, meeting established acceptance criteria. Other validation parameters also conformed to regulatory standards. Ultimately, the efficacy of the method was substantiated in a pharmacokinetic study following a single-dose intravenous administration to mice, underscoring its applicability and reliability in real-world scenarios.

[Regulation effects of intracellular and extracellular Ca2+ on biosynthesis of rosmarinic acid induced by salicylic acid in young seedlings of Salvia miltiorrhiza].

OBJECTIVE: To investigate the effect of intracellular and extracellular Ca2+ on the biosynthesis of rosmarinic acid (RA) induced by salicylic acid in young seedlings of Salvia miltiorrhiza. METHOD: Young seedlings of S. miltiorrhiza were used to select an optimal concentration of salicylic acid (SA), and then use the optimal concentration of SA to investigate the effects of extracellular Ca2+ channel inhibitors Verapamil, LaCl3, intracelluar calmodulin antagonist TFP and intracelluar Ca2+ channel inhibitors LiCl on the biosynthesis of RA and related enzymes. RESULT: SA increased the accumulation of RA and the activities of PAL and TAT, especially the SA of 2 mmol x L(-1) after 24 h. SA improved the accumulation of RA to (40.51 +/- 2.16) mg x g(-1), which was 1.97 times than that of control, and the activities of PAL, TAT were 1.42 times and 1.29 times than those of the control. However, Vp, LaCl3, TFP, LiCl inhibited the effects of SA evidently. CONCLUSION: Ca2+ plays a key role in the regulation of the induction process.

Body surface area is a potential obesity index: Its genetic determination and its causality for later-life diseases.

OBJECTIVE: This study aimed to identify novel genetic factors that contribute to body surface area (BSA) and explore its relationship with complex traits and diseases. METHODS: Based on more than 330,000 European individuals in the UK Biobank, the first large-scale genome-wide association study for BSA was performed. Comprehensive genetic analysis and enrichment analysis were then performed to explore the biological function of the identified loci. The genetic correlations and causal associations between BSA and other anthropometry parameters, early growth indices, and later-life diseases, respectively, were assessed by complex genetic approaches. RESULTS: Genome-wide association study analysis identified a total of 456 conditionally independent single-nucleotide polymorphism mapping genes with known functions in the regulation of adipogenesis and metabolism and enriched in adipogenesis-related pathways. BSA was highly genetically correlated with obesity phenotypes, and all the studied anthropometry parameters from the UK Biobank were significantly positively associated with BSA. BSA was phenotypically associated with 13 chronic diseases and genetically associated with 6 diseases. Mendelian randomization analyses showed that BSA has a causal effect in increasing the risk of some diseases. CONCLUSIONS: These findings increase understanding of genetic determinants for BSA and its relationship with complex traits and diseases, and BSA could be regarded as a potential obesity trait.

Systematic Evaluation of Rheumatoid Arthritis Risk by Integrating Lifestyle Factors and Genetic Risk Scores.

Background: Effective identification of high-risk rheumatoid arthritis (RA) individuals is still a challenge. Whether the combined effects of multiple previously reported genetic loci together with lifestyle factors can improve the prediction of RA risk remains unclear. Methods: Based on previously reported results and a large-scale Biobank dataset, we constructed a polygenic risk score (PRS) for RA to evaluate the combined effects of the previously identified genetic loci in both case-control and prospective cohorts. We then evaluated the relationships between several lifestyles and RA risk and determined healthy lifestyles. Then, the joint effects of healthy lifestyles and genetic risk on RA risk were evaluated. Results: We found a positive association between PRS and RA risk (OR = 1.407, 95% confidence interval (CI) = 1.354~1.463; HR = 1.316, 95% CI = 1.257~1.377). Compared with the low genetic risk group, the group with intermediate or high genetic risk had a higher risk (OR = 1.347, 95% CI = 1.213~1.496; HR = 1.246, 95% CI = 1.108~1.400) (OR = 2.169, 95% CI = 1.946~2.417; HR = 1.762, 95% CI = 1.557~1.995). After adjusting for covariates, we found protective effects of three lifestyles (no current smoking, regular physical activity, and moderate body mass index) on RA risk and defined them as healthy lifestyles. Compared with the individuals with low genetic risks and favorable lifestyles, those with high genetic risks and unfavorable lifestyles had as high as OR of 4.637 (95%CI = 3.767~5.708) and HR of 3.532 (95%CI = 2.799~4.458). Conclusions: In conclusion, the integration of PRS and lifestyles can improve the prediction of RA risk. High RA risk can be alleviated by adopting healthy lifestyles but aggravated by adopting unfavorable lifestyles.

The immune factors have complex causal regulation effects on bone mineral density.

Recent evidence has gradually recognized that the immune and skeletal systems are two closely correlated systems, but the specific immune factors on bone mineral density (BMD) are largely unknown. Based on the summary-level data of genome-wide association studies (GWASs), we performed a series of analyses including two-sample Mendelian randomization (MR) analysis to test potential causal links between 731 immune traits [including median fluorescence intensities (MFIs), absolute cell (AC) counts, relative cell (RC) counts, and morphological parameters (MP)] and BMD. After false discovery rate (FDR) correction, 9 MFI-BMD, 16 AC-BMD, 22 RC-BMD, and 5 MP-BMD pairs reached the level of significance (FDR-adjusted p< 0.05). For MFI traits, the T- and B-cell panels had the largest number of significant immune trait pairs than other panels. CD40, as a molecule expressed by four subsets of monocytes, was highlighted due to its consistently positive correlation with BMD at four sites. For both AC and RC traits, immune traits from the T-cell panel were also highlighted, with CD39-positive T-cell subsets being the most frequently observed feature. For MP traits, the most significant association immune trait with BMD was SSC-A on CD14+ monocyte. Sensitivity analyses suggested that the identified immune factors were robust to pleiotropy. Multivariable MR analysis confirmed the independent causal effect of several immune traits on BMD. Mediation analyses showed that CD40 on monocytes could mediate multiple immune traits, especially the suggestive associations of CD27 on several memory B cells with BMD mediated by CD40 on CD14+ CD16- monocyte. Our study represents the first comprehensive evaluation of the causal effects of immune traits on the risk of osteoporosis. The findings highlighted the complex and important role of immune-derived factors in the pathogenesis of osteoporosis.