Graves' disease and inflammatory bowel disease: A bidirectional Mendelian randomization

Casual associations of thyroid function with inflammatory bowel disease and the mediating role of cytokines

Background

Previous observational epidemiological studies have suggested a potential association between thyroid function and inflammatory bowel disease (IBD). However, the findings remain inconclusive, and whether this association is causal remains uncertain. The objective of this study is to investigate the causal association between thyroid function and IBD.

Methods

Genome-wide association studies (GWAS) involving seven indicators of thyroid function, IBD, and 41 cytokines were analyzed. Bidirectional two-sample Mendelian randomization (MR) and multivariable MR were conducted to examine the causal relationship between thyroid function and IBD and to explore the potential mechanisms underlying the associations.

Results

Genetically determined hypothyroidism significantly reduced the risk of CD (odds ratio [OR] = 0.761, 95% CI: 0.655-0.882, p < 0.001). Genetically determined reference-range TSH was found to have a suggestive causal effect on IBD (OR = 0.931, 95% CI: 0.888-0.976, p = 0.003), (Crohn disease) CD (OR = 0.915, 95% CI: 0.857-0.977, p = 0.008), and ulcerative colitis (UC) (OR =0.910, 95% CI: 0.830-0.997, p = 0.043). In reverse MR analysis, both IBD and CD appeared to have a suggestive causal effect on the fT3/fT4 ratio (OR = 1.002, p = 0.013 and OR = 1.001, p = 0.015, respectively). Among 41 cytokines, hypothyroidism had a significant impact on interferon-inducible protein-10 (IP-10) (OR = 1.465, 95% CI: 1.094-1.962, p = 0.010). The results of multivariable MR showed that IP-10 may mediate the causal effects of hypothyroidism with CD.

Conclusion

Our results suggest that an elevated TSH level reduces the risk of CD, with IP-10 potentially mediating this association. This highlights the pituitary-thyroid axis could serve as a potential therapeutic strategy for CD.

Immune cell signatures and inflammatory mediators: unraveling their genetic impact on chronic kidney disease through Mendelian randomization

Prior research has established associations between immune cells, inflammatory proteins, and chronic kidney disease (CKD). Our Mendelian randomization study aims to elucidate the genetic causal relationships among these factors and CKD. We applied Mendelian randomization using genetic variants associated with CKD from a large genome-wide association study (GWAS) and inflammatory markers from a comprehensive GWAS summary. The causal links between exposures (immune cell subtypes and inflammatory proteins) and CKD were primarily analyzed using the inverse variance-weighted, supplemented by sensitivity analyses, including MR-Egger, weighted median, weighted mode, and MR-PRESSO. Our analysis identified both absolute and relative counts of CD28 + CD45RA + CD8 + T cell (OR = 1.01; 95% CI = 1.01-1.02; p < 0.001, FDR = 0.018) (OR = 1.01; 95% CI = 1.00-1.01; p < 0.001, FDR = 0.002), CD28 on CD39 + CD8 + T cell(OR = 0.97; 95% CI = 0.96-0.99; p < 0.001, FDR = 0.006), CD16 on CD14-CD16 + monocyte (OR = 1.02; 95% CI = 1.01-1.03; p < 0.001, FDR = 0.004) and cytokines, such as IL-17A(OR = 1.11, 95% CI = 1.06-1.16, p < 0.001, FDR = 0.001), and LIF-R(OR = 1.06, 95% CI = 1.02-1.10, p = 0.005, FDR = 0.043) that are genetically predisposed to influence the risk of CKD. Moreover, the study discovered that CKD itself may causatively lead to alterations in certain proteins, including CST5(OR = 1.16, 95% CI = 1.09-1.24, p < 0.001, FDR = 0.001). No evidence of reverse causality was found for any single biomarker and CKD. This comprehensive MR investigation supports a genetic causal nexus between certain immune cell subtypes, inflammatory proteins, and CKD. These findings enhance the understanding of CKD's immunological underpinnings and open avenues for targeted treatments.

Graves' disease and the risk of five autoimmune diseases: A Mendelian randomization and colocalization study

BACKGROUND

Epidemiological studies have consistently demonstrated a high prevalence of concurrent autoimmune diseases in individuals with Graves' disease (GD).

OBJECTIVE

The objective of this study is to establish a causal association between GD and autoimmune diseases.

METHODS

We employed a two-sample Mendelian randomization (MR) to infer a causal association between GD and five autoimmune diseases, namely rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Crohn's disease (CD), ulcerative colitis (UC), and amyotrophic lateral sclerosis (ALS), in the East Asian and European population. Genetic correlations were explored through linkage disequilibrium score regression analysis (LDSC). Finally, colocalization analyses were performed to investigate possible genetic foundations.

RESULTS

Bidirectional MR analysis indicated that genetically predicted GD increased the risk of RA (Odds Ratio (OR): 1.34, 95 % Confidence Interval (CI): 1.21 to 1.47, P < 0.001) and SLE (OR: 1.21, 95%CI: 1.08 to 1.35, P < 0.001) in the East Asian population. In contrast, we found that genetically predicted RA (OR: 1.14, 95%CI: 1.05 to 1.24, P = 0.002) and SLE (OR: 1.10, 95%CI: 1.03 to 1.17, P = 0.003) were associated with a higher risk of GD. The results have been partially validated in European cohorts. Colocalization analysis suggested the potential existence of shared causal variants between GD and other autoimmune diseases. In particular, gene ARID5B may play an important role in the incidence of autoimmune diseases.

CONCLUSION

This study has confirmed that GD was associated with RA and SLE and found a possible key gene ARID5B. It may be necessary to strengthen detection to prevent the occurrence of comorbidities in clinical practice.

Investigation of the causal relationship between inflammatory bowel disease and type 2 diabetes mellitus: a Mendelian randomization study

Background: Type 2 diabetes mellitus (T2DM) and inflammatory bowel disease (IBD) have been associated, according to various epidemiological research. This study uses Mendelian randomization (MR) to investigate the causal link between T2DM and IBD. Methods: To investigate the causal relationship between IBD and T2DM risk using European population data from the genome-wide association study (GWAS) summary datasets, we constructed a two-sample MR study to evaluate the genetically predicted impacts of liability towards IBD outcomes on T2DM risk. As instrumental variables (IVs), we chose 26 single nucleotide polymorphisms (SNPs) associated with IBD exposure data. The European T2DM GWAS data was obtained from the IEU OpenGWAS Project database, which contains 298,957 cases as the outcome data. The causal relationship between T2DM and IBD using a reverse MR analysis was also performed. Results: The two-sample MR analysis, with the Bonferroni adjustment for multiple testing, revealed that T2DM risk in Europeans is unaffected by their IBD liability (odds ratio (OR): 0.950-1.066, 95% confidence interval (CI): 0.885-1.019, p = 0.152-0.926). The effects of liability to T2DM on IBD were not supported by the reverse MR analysis either (OR: 0.739-1.131, 95% confidence interval (CI): 0.651-1.100, p = 0.058-0.832). MR analysis of IBS on T2DM also have no significant causal relationship (OR: 0.003-1.007, 95% confidence interval (CI): 1.013-5.791, p = 0.069-0.790). FUMA precisely mapped 22 protein-coding genes utilizing significant SNPs of T2DM acquired from GWAS. Conclusion: The MR study showed that the existing evidence did not support the significant causal effect of IBD on T2DM, nor did it support the causal impact of T2DM on IBD.

Causal Relationship between Immune Cells and Gynecological Cancers through Bidirectional and Multivariable Mendelian Randomization Analyses

Background: Evidence suggests potential associations between gynecological malignancies and various immune cell chemicals and systems. However, establishing a causal relationship remains uncertain. Methods: This work employed Wald ratio for one single-nucleotide polymorphism (SNP) or the inverse-variance weighted method (IVW) for multiple SNPs to conduct bidirectional two-sample Mendelian randomization (MR) analysis by utilizing genome-wide association study (GWAS) data. We employed supplementary methods, including MR-Egger and weighted median methods, to detect and correct for the influence of horizontal pleiotropy. In addition, we also use colocalization analysis for further validation. Results: In IVW analysis, increases in relative count of circulating CD11c+ HLA-DR++ conventional dendritic cells (cDC) were associated with an elevated risk of breast cancer (OR [95% CI], 1.1295 [1.0632-1.2000], P = 8.044 × 10-5), while elevated levels of HLA-DR on plasmacytoid dendritic cells (DC) and HLA-DR on DC were protective against breast cancer. In addition, actual count of CD39+ resting Treg AC was also shown to be causally associated with the development of ovarian cancer, whereas a high relative count of CD28+ CD45RA- CD8+ T cells reduced the risk of cervical cancer. Sensitivity analysis revealed almost no evidence of bias in the current study. Multivariable MR (MVMR) analyses further confirmed a direct impact of the CD11c+ HLA-DR++ cDC immune phenotype on breast cancer. Colocalization analysis showed the lead SNP, rs780094, suggesting HLA-DR GWAS shared a common genetic mechanism with breast cancer. Conclusions: The MR study identified significant causal relationships between multiple immunophenotypes and breast cancer, aiming to provide clinicians with some reference for cancer prediction and explore further potential associations between immune phenotypes and gynecologic tumors.

Repurposing TAK875 as a novel STAT3 inhibitor for treating inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic immune-mediated disease associated with a high recurrence rate and an elevated risk of colon cancer. In this study, we screened a bioactive compound library using a luciferase reporter assay and identified the compound TAK875 as a novel inhibitor of signal transducer and activator of transcription 3 (STAT3). Surface plasmon resonance analysis, differential scanning fluorimetry, and isothermal titration calorimetry demonstrated that TAK875 directly bound to recombinant STAT3. TAK875 suppressed the lipopolysaccharide (LPS)-induced release of nitric oxide, inducible nitric oxide synthase, and inflammatory factors in RAW264.7 cells, likely by inhibiting STAT3 phosphorylation. In addition, TAK875 inhibited the differentiation of CD4+ T cells into T-helper 17 cells, which may partially account for its anti-inflammatory effect. TAK875 also alleviated the LPS-induced accumulation of intracellular reactive oxygen species, thus displaying its antioxidant effects. Finally, we demonstrated its satisfactory anti-inflammatory effect in a dextran sulfate sodium-induced mouse model of ulcerative colitis. In conclusion, this study presented TAK875 as a novel STAT3 inhibitor and demonstrated its anti-inflammatory and antioxidant effects both in vitro and in vivo.

Potential Causal Association between Depression and Oral Diseases: A Mendelian Randomization Study

BACKGROUND

Globally, oral diseases are common, pose an economic burden, and significantly decline the quality of life of affected individuals. Recently, researchers have substantially highlighted the effect of depression on oral disease incidence and development. In this study, we elucidated the correlation between depression and oral diseases.

METHODS

Using two-sample Mendelian randomization (MR), the association between depression and the risk of 17 oral diseases was evaluated. Three methods were used to perform MR analysis: the inverse variance-weighted, weighted median, and MR-Egger methods. Furthermore, Cochran's Q test, MR-Egger intercept test, MR Pleiotropy RESidual Sum and Outlier test, and leave-one-out analysis were performed to analyze sensitivity.

RESULTS

After implementing multiple test corrections, we observed that genetic susceptibility to depression was associated with an increased risk of mouth ulcers, toothache, loose teeth, bleeding gums, painful gums, chronic periodontitis, chronic tonsil and adenoid diseases, peritonsillar abscess, and excessive tooth attrition. However, a causal relationship between depression and other oral diseases was not observed. Sensitivity analysis confirmed the robustness of the results.

CONCLUSIONS

We confirmed the causal relationship between depression and several oral diseases, thereby providing a novel viewpoint on the prevention and treatment of oral diseases. Our findings suggest the integration of depression control into routine clinical care to enhance the effectiveness of oral disease treatment.