TSH receptor autoantibody levels post-total thyroidectomy in Graves' ophthalmopathy: a meta-analysis.

BACKGROUND: TSH receptor autoantibodies (TRAbs) are pathognomonic for Graves' disease and are thought to also underly the pathogenesis of Graves' ophthalmopathy (GO). A decline in TRAb levels has been documented post-total thyroidectomy (TTx) in GO, however with conflicting correlations with disease outcomes. The aim of the study was to compare the effectiveness of TTx to other treatment modalities of Graves' disease and examine whether the lowering of TRAbs is associated with GO improvements. METHOD: We searched electronic databases including Medline, Embase, Scopus, and Web of Science until 31 September 2022 using a broad range of keywords. Patients with GO undergoing TTx with measurements of both TRAbs and progression of the disease using a validated GO scoring system were included. Fourteen studies encompassing data from 1047 patients with GO met our eligibility criteria. The PRISMA guidelines were followed, and five studies had comparable data that were suitable for a meta-analysis. RESULTS: The Cochrane Risk of Bias tool for RCTs showed low risk of bias across most domains. The pooled odds ratio showed that more patients significantly had normalized TRAb levels post-TTx as compared to other interventions (OR: 1.36, 95% CI: 1.02-1.81, p = 0.035). But, there was no significant difference in GO improvement post-TTx as compared with other intervention groups. CONCLUSIONS: This meta-analysis shows that TRAb levels may decline largely post-TTx, but may not predict added improvements to the progression of GO. Thus, future studies with uniform designs are required to assess the minimal significant GO improvements.

DNA Methylation Reduces the Yes-Associated Protein 1/WW Domain Containing Transcription Regulator 1 Pathway and Prevents Pathologic Remodeling during Bladder Obstruction by Limiting Expression of BDNF.

Chronic bladder obstruction and bladder smooth muscle cell (SMC) stretch provide fibrotic and mechanical environments that can lead to epigenetic change. Therefore, we examined the role of DNA methylation in bladder pathology and transcriptional control. Sprague-Dawley female rats underwent partial bladder obstruction by ligation of a silk suture around the proximal urethra next to a 0.9-mm steel rod. Sham operation comprised passing the suture around the urethra. After 2 weeks, rats were randomized to normal saline or DNA methyltransferase inhibitor, 5-aza-2-deoxycytidine (DAC) at 1 mg/kg, three times/week intraperitoneally. After 6 weeks, bladders were weighed and divided for histology and RNA analysis by high-throughput real-time quantitative PCR arrays. DAC treatment during obstruction in vivo profoundly augmented brain-derived neurotrophic factor (BDNF) expression compared with the obstruction with vehicle group, which was statistically correlated with pathophysiologic parameters. BDNF, cysteine rich angiogenic inducer 61 (CYR61), and connective tissue growth factor (CTGF) expression clustered tightly together using Pearson's correlation analysis. Their promoters were associated with the TEA domain family member 1 (TEAD1) and Yes-associated protein 1/WW domain containing transcription regulator 1 pathways. Interestingly, DAC treatment increased BDNF expression in bladder SMCs (P < 0.0002). Stretch-induced BDNF was inhibited by the YAP/WWTR1 inhibitor verteporfin. Verteporfin improved the SMC phenotype (proliferative markers and SMC marker expression), in part by reducing BDNF. Expression of BDNF is limited by DNA methylation and associated with pathophysiologic changes during partial bladder outlet obstruction and SMC phenotypic change in vitro.