Pro-fibrotic effect of the susceptible gene PCSK5 in vascular fibrosis of Takayasu arteritis via TGF-ß and SMAD3 signaling pathway activation.

BACKGROUND: Vascular fibrosis directly causes vascular thickening in Takayasu arteritis (TAK), in which sustained transforming growth factor beta (TGF-ß) activation is critical. Understanding TGF-ß activation regulation and blocking it might yield a therapeutic effect in TAK. Proprotein convertase subtilisin/kexin type 5 (PCSK5) rs6560480 (T/C) is associated with TAK development. In this study, we assessed the association between the PCSK5 rs6560480 genotype and PCSK5 expression in TAK and explored its molecular role in TGF-ß activation and vascular fibrosis development. METHODS: In TAK patients, PCSK5 and TGF-ß expression in plasma and aortic tissue was examined by ELISA and immunohistochemical staining, and PCSK5 rs6560480 was genotyped. The correlation between PCSK5 and extracellular matrix (ECM) expression was examined by Western blotting (WB) and immunohistochemistry staining. Detection by co-immunoprecipitation was performed to detect the interaction between PCSK5 and TGF-ß in adventitial fibroblasts (AAFs). Downstream signaling pathways were detected by WB and validated with appropriate inhibitors. Potential immunosuppressive agents to inhibit the effects of PCSK5 were explored in cell culture and TAK patients. RESULTS: Patients with PCSK5 rs6560480 TT patients had significantly higher PCSK5 levels and more thickened vascular lesions than patients with PCSK5 rs6560480 CT. PCSK5 expression was significantly increased in alpha smooth muscle actin (α-SMA)-positive myofibroblasts in TAK vascular lesions. Overexpressing PCSK5 facilitated TGF-ß and downstream SMAD2/3 activation and ECM expression in AAFs and aorta in in-vitro culture. The mechanistic study supported that PCSK5 activated precursor TGF-ß (pro-TGF-ß) to the mature form by binding the pro-TGF-ß cleavage site. Leflunomide inhibited PCSK5 and pro-TGF-ß binding, decreasing TGF-ß activation and ECM expression, which was also partially validated in leflunomide-treated patients. CONCLUSION: The findings revealed a novel pro-fibrotic mechanism of PCSK5 in TAK vascular fibrosis via TGF-ß and downstream SMAD2/3 pathway activation. Leflunomide might be anti-fibrotic by disrupting PCSK5 and pro-TGF-ß binding, presenting a new TAK treatment approach.

Efficacy of borneol-gypsum in skin regeneration and pain control in toxic epidermal necrolysis: A case report.

BACKGROUND: Toxic epidermal necrolysis (TEN) is a life-threatening dermatological emergency mainly induced by drug hypersensitivity reactions. Standard management includes discontinuation of culprit drug and application of immunomodulatory therapy. However, mortality remains high due to complications like septic shock and multiorgan failures. Innovative approaches for skin care are crucial. This report introduces borneol-gypsum, a traditional Chinese drug but a novel dressing serving as an adjuvant of TEN therapy, might significantly improve skin conditions and patient outcomes in TEN. CASE SUMMARY: A 38-year-old woman diagnosed with eosinophilic granulomatosis with polyangiitis experienced gangrenous complications and motor nerve involvement. After initial treatment of high-dose corticosteroids and cyclophosphamide, symptom of foot drop improved, absolute eosinophil counts decreased, while limb pain sustained. Duloxetine was added to alleviate her symptom. Subsequently, TEN developed. Additional topical application of borneol-gypsum dressing not only protected the skin lesions from infection but also significantly eased localized pain. This approach demonstrated its merit in TEN management by promoting skin healing and potentially reducing infection risks. CONCLUSION: Borneol-gypsum dressing is a promising adjuvant that could significantly improve TEN management, skin regeneration, and patient comfort.

SERPINA3, FGA, AGP1, ITIH3 and SAA1 as novel biomarkers for eosinophilic granulomatosis with polyangiitis diagnosis and activity assessment.

OBJECTIVE: To identify novel biomarkers for diagnosis and prediction of active eosinophilic granulomatosis with polyangiitis (EGPA) through data-independent acquisition (DIA) analysis. METHODS: Plasma from 11 EGPA patients and 10 healthy controls (HCs) were analyzed through DIA to identify potential biomarkers. The results were validated in 32 EGPA patients, 24 disease controls (DCs), and 20 HCs using enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve was used to assess the diagnostic value of candidate biomarkers. RESULTS: Thirty-five differentially expressed proteins (DEPs) (24 upregulated and 11 downregulated) were screened between EGPA and HC groups. Five proteins, including serine proteinase inhibitor A3 (SERPINA3), alpha-fibrinogen (FGA), alpha-1 acid glycoprotein 1(AGP1), inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3), and serum amyloid A1 (SAA1), were significantly upregulated in EGPA compared with HCs. Apart from SAA1, all proteins were also higher in EGPA patients compared with DCs. Furthermore, a panel of SERPINA3 and SAA1 exhibited potential diagnostic value for EGPA with an area under the curve (AUC) of 0.953, while a panel of SERPINA3, FGA, AGP1, and ITIH3 showed good discriminative power to differentiate EGPA from DCs with AUC of 0.926. Moreover, SERPINA3, FGA, and AGP levels were significantly higher in active EGPA and correlated well with disease activity. A combination of SERPINA3 and AGP1 exhibited an excellent AUC of 0.918 for disease activity assessment. CONCLUSION: SERPINA3, FGA, AGP1, ITIH3 and SAA1 were identified as potential biomarkers for EGPA diagnosis and disease activity assessment. Among them, as a single biomarker, SERPINA3 has the best diagnostic performance.

BACH1 controls hepatic insulin signaling and glucose homeostasis in mice.

Hepatic insulin resistance is central to the metabolic syndrome. Here we investigate the role of BTB and CNC homology 1 (BACH1) in hepatic insulin signaling. BACH1 is elevated in the hepatocytes of individuals with obesity and patients with non-alcoholic fatty liver disease (NAFLD). Hepatocyte-specific Bach1 deletion in male mice on a high-fat diet (HFD) ameliorates hyperglycemia and insulin resistance, improves glucose homeostasis, and protects against steatosis, whereas hepatic overexpression of Bach1 in male mice leads to the opposite phenotype. BACH1 directly interacts with the protein-tyrosine phosphatase 1B (PTP1B) and the insulin receptor ß (IR-ß), and loss of BACH1 reduces the interaction between PTP1B and IR-ß upon insulin stimulation and enhances insulin signaling in hepatocytes. Inhibition of PTP1B significantly attenuates BACH1-mediated suppression of insulin signaling in HFD-fed male mice. Hepatic BACH1 knockdown ameliorates hyperglycemia and improves insulin sensitivity in diabetic male mice. These results demonstrate a critical function for hepatic BACH1 in the regulation of insulin signaling and glucose homeostasis.

COVID-19 infection characteristics, risk factors and its potential impacts on Takayasu arteritis: a web-based survey in a large cohort.

Objectives: To investigate the characteristics of COVID-19 and its impact on patients with Takayasu's arteritis (TAK). Methods: A web-based survey was administered to a TAK cohort and their co-residents in China during January 2023. Infection symptoms, post-acute sequelae of COVID-19 (PASC), potential impacts of COVID-19 on patients' disease condition, treatment and immune-related parameters were analyzed. In addition, risk factors for COVID-19 and disease relapse after infection were explored. Results: The infection rate was significantly lower in patients with TAK than in co-residents (79.13% vs 90.67%, p=0.025). TAK patients were more prone to gastrointestinal symptoms (17.78% vs 5.88%, p=0.024), sleep problems (25.15% vs 10.29%, p=0.011), and symptoms involving more than 2 organs (58.90% vs 35.29%, p=0.001) after infection. Although only 2.45% of TAK patients were hospitalized and none progressed to life-threatening conditions, they were more likely to suffer from PASC (26.38% vs 13.24%, p=0.029), especially active patients. Active disease after the pandemic was significantly lower in infected patients than uninfected patients (21/163, 12.88% vs. 11/43, 25.58%, p=0.041). The presence of multiple system symptoms was a risk factor for active TAK after infection [OR: 3.62 (95% CI 1.06-12.31), p=0.040]. Moreover, csDMARDs treatment was a risk factor for COVID-19 infection [OR: 3.68 (95% CI 1.56-8.66), p=0.002]. Conclusion: Although TAK patients with COVID-19 have more acute and post-acute symptoms, there is no adverse outcome and the risk of disease relapse does not increase. Patients treated with csDMARDs may be at higher risk of infection and deserve more clinical attention.