The interference of anti-TSH autoantibody on clinical TSH detection.

Objective: It is well known that macro-thyroid-stimulating hormone (macro-TSH) could interfere with the detection of TSH. The anti-TSH autoantibody is an essential component of macro-TSH. However, the epidemiological characteristics and the clinical interference of the anti-TSH autoantibody are unclear. Methods: In this study, the radioimmunoprecipitation technique was used to detect the anti-TSH autoantibody. Platforms with different detection mechanisms were applied to measure the TSH in patients with the anti-TSH autoantibody. Polyethylene glycol (PEG) precipitation was used to determine the immunoassay interference. Results: The prevalence of the anti-TSH autoantibody in patients with mild subclinical hypothyroidism (SCH) and autoimmune thyroiditis, but normal thyroid function, was 4.78%. All 10 patients with anti-TSH antibodies had autoimmune diseases, with five of them having significant clinical test interference. Conclusion: The appearance of the anti-TSH antibody is not associated with thyroid autoantibodies. The presence of the anti-TSH autoantibody can interfere with the detection of TSH and can affect clinical diagnosis and treatment.

Non-thyroidal disease syndrome in patients with systemic lupus erythematosus: relation to disease inflammatory activity.

OBJECTIVE: To identify risk factors for the development of non-thyroidal illness syndrome (NTIS) in patients with systemic lupus erythematosus (SLE). METHODS: A retrospective analysis of 517 SLE patients and 1034 age-and sex-matched healthy population was conducted to compare the prevalence of NTIS in these two groups, and to analyze the laboratory and clinical characteristics of SLE patients with NTIS. Finally Logistic regression analysis was used to determine the risk factors for NTIS in SLE patients. RESULTS: The prevalence of NTIS in the SLE patients was significantly higher than that in controls (39.7% vs. 1.0%, P < 0.001). In SLE patients, compared with euthyroidism patients, NTIS patients exhibited higher levels of neutrophils, hepatic enzymes, kidney damage markers, inflammatory markers and SLE disease activity index (SLEDAI). They also had a higher incidence of organ insufficiency and positive antibodies such as anti-ds-DNA antibodies and anti-SSA antibodies. However, NTIS patients had lower levels of hemoglobin, lymphocytes, platelets, serum albumin, and complement. Additionally, NTIS patients had a shorter duration of lupus and lower utilization of disease-modifying antirheumatic drugs (DMARDs) (P < 0.05). Logistic regression analysis showed that elevated SLEDAI (OR = 1.060, 95%CI 1.022-1.099, P = 0.002), elevated systemic immune-inflammation index (SII) (OR = 1.003, 95%CI 1.001-1.007, P = 0.026), elevated erythrocyte sedimentation rate (ESR) (OR = 1.019, 95%CI 1.010-1.028, P < 0.001), and hepatic insufficiency (OR = 1.916, 95% CI 1.173-3.131, P = 0.009) were independent risk factors for the development of NTIS in SLE. DMARDs treatment (OR = 0.495, 95% CI 0.306-0.799, P < 0.001) was an independent protective factor for NTIS. CONCLUSIONS: Inflammatory activity in SLE patients is associated with the development of NTIS. Key Points • Inflammatory activity indexes such as SLEDAI, SII, and ESR are independent risk factors for NTIS in SLE patients.

The causal relationship between autoimmune thyroid disorders and telomere length: A Mendelian randomization and colocalization study.

This study aimed to evaluate whether there is a causal relationship between autoimmune thyroid disorders (AITDs) and telomere length (TL) in the European population and whether there is reverse causality. In this study, Mendelian randomization (MR) and colocalization analysis were conducted to assess the potential causal relationship between AITDs and TL using summary statistics from large-scale genome-wide association studies, followed by analysis of the relationship between TL and thyroid stimulating hormone and free thyroxine (FT4) to help interpret the findings. The inverse variance weighted (IVW) method was used to estimate the causal estimates. The weighted median, MR-Egger and leave-one-out methods were used as sensitivity analyses. The IVW method results showed a significant causal relationship between autoimmune hyperthyroidism and TL (ß = -1.93 × 10-2 ; p = 4.54 × 10-5 ). There was no causal relationship between autoimmune hypothyroidism and TL (ß = -3.99 × 10-3 ; p = 0.324). The results of the reverse MR analysis showed that genetically TL had a significant causal relationship on autoimmune hyperthyroidism (IVW: odds ratio (OR) = 0.49; p = 2.83 × 10-4 ) and autoimmune hypothyroidism (IVW: OR = 0.86; p = 7.46 × 10-3 ). Both horizontal pleiotropy and heterogeneity tests indicated the validity of our bidirectional MR study. Finally, colocalization analysis suggested that there were shared causal variants between autoimmune hyperthyroidism and TL, further highlighting the robustness of the results. In conclusion, autoimmune hyperthyroidism may accelerate telomere attrition, and telomere attrition is a causal factor for AITDs.

Association Between Educational Attainment and Thyroid Function: Results From Mendelian Randomization and the NHANES Study.

CONTEXT: Many observational studies have reported on the association between educational attainment (EA) and thyroid function, but the causal relationship remains unclear. OBJECTIVE: We aimed to obtain causal effects of EA on thyroid function and to quantify the mediating effects of modifiable risk factors. METHODS: Two-sample mendelian randomization (MR) was performed by using summary statistics from large genome-wide association studies (GWAS) to assess the effect of EA on thyroid function, including hypothyroidism, hyperthyroidism, thyrotropin (TSH), and free thyroxine (FT4). A multivariable analysis was conducted to assess the mediating role of smoking and help to explain the association between EA and thyroid function. Similar analysis was further performed using data from the National Health and Nutrition Examination Survey (NHANES) 1999 to 2002. RESULTS: In MR analysis, EA was causally associated with TSH (ß = .046; 95% CI, 0.015-0.077; P = 4.00 × 10-3), rather than hypothyroidism, hyperthyroidism, and FT4. Importantly, smoking could serve as a mediator in the association between EA and TSH, in which the mediating proportion was estimated to be 10.38%. After adjusting for smoking in the multivariable MR analysis, the ß value of EA on TSH was attenuated to 0.030 (95% CI, 0.016-0.045; P = 9.32 × 10-3). Multivariable logistic regression model in NHANES suggested a dose-response relationship between TSH (quartile [Q]4 vs Q1: odds ratio = 1.33; 95% CI, 1.05-1.68; P for trend = .023) and EA. Smoking, systolic blood pressure, and body mass index partially mediated the association between EA and TSH, with the proportion of the mediation effects being 43.82%, 12.28%, and 6.81%, respectively. CONCLUSION: There is a potentially causal association between EA and TSH, which could be mediated by several risk factors, such as smoking.

Identification and Validation of Hub Immune-Related Genes in Non-Alcoholic Fatty Liver Disease.

Background: Nonalcoholic fatty liver disease (NAFLD) is the most common progressive liver disease worldwide. It can cause liver cancer and possibly death. Abnormal immune infiltration is involved in the progression of NAFLD. The aim of this study was to identify and validate the hub immune-related genes in NAFLD. Methods: Microarray data were downloaded from Gene Expression Omnibus, and immune-related differentially expressed genes (IRDEGs) were obtained. A protein-protein interaction network was used to further screen. The diagnostic value of the IRDEGs was evaluated by receiver operating characteristic curves. Differences in immune infiltration levels were analyzed using single-sample gene set enrichment analysis. Hub IRDEGs were identified by correlation analysis with immune infiltration levels. Finally, molecular experiments were used to confirm the expression of the hub IRDEGs and explore their roles in NAFLD. Results: We obtained 18 IRDEGs. Five hub genes were further identified by protein-protein interaction network, receiver operating characteristic curves and correlation analysis: AQP9, BACH2, CD4, IL17RE and S100A9. Based on functional enrichment analysis, the hub genes were enriched primarily in many immune-related pathways. In NAFLD, AQP9, CD4, and IL17RE expression was significantly reduced, whereas BACH2 and S100A9 expression was elevated. PCR, oil red O staining and triglyceride detection revealed that the knock-down of BACH2 and S100A9 reduced lipid accumulation in NAFLD cells. Conclusion: This study provided insight into the profile of immune infiltration underlying NAFLD and identified AQP9, BACH2, CD4, IL17RE and S100A9 as ancillary diagnostic indicators of NAFLD. And BACH2 and S100A9 might be therapeutic targets for NAFLD.

Association Between Systemic Lupus Erythematosus and Primary Hypothyroidism: Evidence from Complementary Genetic Methods.

INTRODUCTION: Systemic lupus erythematosus (SLE) and hypothyroidism often coexist in observational studies; however, the causal relationship between them remains controversial. METHODS: Complementary genetic approaches, including genetic correlation, Mendelian randomization (MR), and colocalization analysis, were conducted to assess the potential causal association between SLE and primary hypothyroidism using summary statistics from large-scale genome-wide association studies. The association between SLE and thyroid-stimulating hormone (TSH) was further analyzed to help interpret the findings. In addition, findings were verified using a validation data set, as well as through different MR methods with different model assumptions. RESULTS: The linkage disequilibrium score regression revealed a shared genetic structure between SLE and primary hypothyroidism, with the significant genetic correlation estimated to be 0.2488 (P = 6.00 × 10-4). MR analysis with the inverse variance weighted method demonstrated a bidirectional causal relationship between SLE and primary hypothyroidism. The odds ratio (OR) of SLE on primary hypothyroidism was 1.037 (95% CI, 1.013-1.061; P = 2.00 × 10-3) and that of primary hypothyroidism on SLE was 1.359 (95% CI, 1.217-1.520; P < 0.001). The OR of SLE on TSH was 1.007 (95% CI, 1.001-1.013; P = 0.032). However, TSH was not causally associated with SLE (P = 0.152). Similar results were found using different MR methods. In addition, colocalization analysis suggested that shared causal variants existed between SLE and primary hypothyroidism. The results of the validation analysis indicated a bidirectional causal relationship between SLE and primary hypothyroidism, as well as shared loci. CONCLUSION: In summary, a bidirectional causal relationship between SLE and primary hypothyroidism was observed with complementary genetic approaches.

Investigating causal associations among gut microbiota, metabolites and autoimmune hypothyroidism: a univariable and multivariable Mendelian randomization study.

Background: Accumulating evidence suggests that the gut microbiota and its metabolites may be involved in autoimmune hypothyroidism. However, the causal association between gut microbiota, metabolites and autoimmune hypothyroidism remains to be determined. Methods: Instrumental variables were screened from the GWAS datasets of 211 gut microbiota taxonomic groups, gut microbiota-derived metabolites, and autoimmune hypothyroidism. Univariable Mendelian randomization (MR) and multivariable Mendelian randomization (MVMR) were used to analyse the potential causal relationship between autoimmune hypothyroidism, these metabolites, or these microbiota. During the MR analysis, we alternated multiple MR methods with different model assumptions to assess the consistency and robustness of the findings: inverse variance weighted (IVW), weighted median, MR pleiotropy residual sum and outlier (MRPRESSO) and MR-Egger methods. Reverse MR analysis was performed to assess the possibility of reverse causality. Finally, enrichment analyses were used to investigate potential biofunctions. Results: The IVW results of univariable MR showed that the phyla Actinobacteria, genus DefluviitaleaceaeUCG011, genus Eggerthella, family Defluviitaleaceae, genus Subdoligranulum, genus RuminococcaceaeUCG011, and genus Intestinimonas were associated with autoimmune hypothyroidism. After FDR adjustment, the absence of a causal relationship between gut microbiota and autoimmune hypothyroidism (PFDR > 0.05) suggested a possible marginal association. The results on gut metabolites showed that N-(3-furoyl)glycine, pipecolate, phenylalanine, allantoin, indololactate and alanine were associated with autoimmune hypothyroidism. After FDR correction, only indololactate was associated with hypothyroidism (OR=1.592; 95% CI, 1.228-2.065; PFDR= 0.036). Family Defluviitaleaceae and genus DefluviitaleaceaeUCG011 were suggestively significant in the MVMR. The results of reverse MR analysis showed no reverse causality between autoimmune hypothyroidism and the identified gut microbiota. Enrichment analysis revealed that several key regulatory pathways were significantly enriched. Conclusion: This study supported that there were beneficial or detrimental causal effects of gut microbiota and its metabolites on autoimmune hypothyroidism risk, which provides more theoretical support for mechanistic research on the "thyroid-gut" axis.

High prevalence of thyroid hormone autoantibody and low rate of thyroid hormone detection interference.

OBJECTIVE: Thyroid hormone autoantibody (THAb) is a common antibody in autoimmune disease and can interfere with the detection of thyroid hormone (TH). There was no research reporting the prevalence of THAb in Chinese and the rate of THAb interfering with TH detection. METHODS: We collected 114 patients with autoimmune thyroid disease (AITD) (Hashimoto's thyroiditis, 57 cases; Graves' disease, 57 cases), 106 patients with nonthyroid autoimmune diseases (NTAID), and 120 healthy subjects. According to the presence or absence of thyroid antibodies, patients with NTAID were divided into two groups: NTAID-AITD and NTAID groups. Radioimmunoprecipitation technique was used to detect THAb in all subjects. TH was detected on Abbot and Roche platforms in patients with positive THAb. RESULTS: The prevalence of THAb was 22.8% in Hashimoto's thyroiditis and 45.6% in Graves' disease. The prevalence of THAb in AITD group was lower than that in NTAID or NTAID-AITD groups (34.2% vs. 61.5%, p = 0.014; 34.2% vs. 71.3%, p < 0.01). Among total 98 patients with positive THAb, TH levels of 9 patients were falsely elevated (9.18%). CONCLUSION: The prevalence of THAb in AITD patients was lower than that in NTAID patients. Although THAb had a high frequency in various autoimmune diseases, the prevalence of THAb interfering with TH detection was only 9.18%.

Presence of TSHR in NK Cells and Action of TSH on NK Cells.

INTRODUCTION: Thyroid-stimulating hormone receptor (TSHR) is widely expressed in human tissues and cells. TSHR is not only involved in thyroid disease but also in the neuroendocrine-immune regulatory network. However, no study has exclusively focused on the expression and function of TSHR in natural killer (NK) cells. METHODS: We studied TSHR expression using reverse transcription PCR to verify TSHR mRNA transcripts in human and mouse NK cells. Human and mouse thyroid and liver tissues as well as peripheral blood mononuclear cells (PBMCs) or spleen lymphoid cells (SLCs) were used as controls. The TSHR protein levels in NK-92 cells were determined by immunofluorescence staining. The function of TSHR in NK cells was investigated by measuring the TSH-stimulated cAMP levels. RESULTS: TSHR mRNA was detected in human and mouse NK cells as well as in NK-92 cells and had the same sequence as that of thyroid-derived, PBMC-derived, and liver-derived mRNA. The TSHR protein was also expressed in the cell membrane of NK-92 cells. Furthermore, the cAMP levels in NK-92 cells were significantly higher after adding 102 mIU/mL of bovine TSH at p < 0.05, which stimulated cAMP production in NK-92 cells. CONCLUSIONS: Our findings confirm that TSHR is present and functional in NK cells and provide key clues for the potential regulatory effects of TSH on TSHR in NK cells in the immune system.

Involvement of the ERK pathway in the protective effects of glycyrrhizic acid against the MPP+-induced apoptosis of dopaminergic neuronal cells.

Glycyrrhizic acid (GA), a major compound separated from Radix Glycyrrhizae, has been shwon to exert various biochemical effects, including neuroprotective effects. In the present study, we investigated the protective effects of GA against 1-methyl-4-phenylpyridinium (MPP+)­induced damage to differentiated PC12 (DPC12) cells. Compared with the MPP+-treated cells, GA markedly improved cell viability, restored mitochondrial dysfunction, suppressed the overexpression of cleaved poly(ADP-ribose) polymerase (PARP), and suppressed the overproduction of lactate dehydrogenase (LDH) and intracellular Ca2+ overload. The protective effects of GA on cell survival were further confirmed in primary cortical neurons. GA markedly increased the expression of phosphorylated extracellular signal-regulated kinase (p-ERK), as well as its migration from the cytoplasm to nucleus. PD98059, an inhibitor of ERK, blocked GA-enhanced ERK activation and reduced cell viability. However, pre-treatment with GA had no effects on the expression of phosphorylated AKT (p-AKT) and total AKT (t-AKT). These results indicate that the GA-mediated neuroprotective effects are associated with its modulation of multiple anti-apoptotic and pro-apoptotic factors, particularly the ERK signaling pathway. This study provides evidence supporting the use of GA as a potential therapeutic agent for the treatment of neurodegenerative diseases and neuronal injury.