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Objective: It has been reported that ADAMTS‐12 is a susceptibility gene for rheumatoid arthritis (RA) development, and its level is significantly increased in RA patients. In addition, ADAMTS‐12 is reported to be required for inflammation in otherwise healthy subjects. This study was undertaken to determine the role of ADAMTS‐12 and the underlying mechanisms in the pathogenesis of inflammatory arthritis. Methods: The collagen‐induced arthritis (CIA) model was established in ADAMTS‐12–deficient mice and their control littermates to determine the role of ADAMTS‐12 in vivo. Micro–computed tomography scanning was used to demonstrate the destruction of the ankle joint; histologic analysis illustrated synovitis, pannus formation, and bone and cartilage destruction; enzyme‐linked immunosorbent assay was performed to measure serum levels of inflammatory cytokines; and protein–protein interaction assays were performed to detect the interactions of ADAMTS‐12 and its various deletion mutants with connective tissue growth factor (CTGF). Results: Deficiency of ADAMTS‐12 led to accelerated inflammatory arthritis in the CIA mouse model. Loss of ADAMTS‐12 caused enhanced osteoclastogenesis. In vitro and in vivo protein–protein interaction assays demonstrated that ADAMTS‐12 bound and processed CTGF, a previously unrecognized substrate of ADAMTS‐12. In addition, deletion of ADAMTS‐12 enhanced, while overexpression of ADMATS‐12 reduced, CTGF‐mediated inflammation. Furthermore, ADAMTS‐12 regulation of inflammation was largely lost in CTGF‐deficient macrophages. Importantly, blocking of CTGF attenuated elevated inflammatory arthritis seen in the ADAMTS‐12–deficient CIA mouse model. Conclusion: This study provides evidence that ADAMTS‐12 is a critical regulator of inflammatory arthritis and that this is mediated, at least in part, through control of CTGF turnover. [ABSTRACT FROM AUTHOR]

Ershiwuwei Lvxue Pill (ELP, མགྲིན་མཚལ་ཉེར་ལྔ།), a traditional Tibetan medicine preparation, has been used hundreds of years for the clinical treatment of rheumatoid arthritis (RA) in the highland region of Tibet, China. However, the underlying mechanism of its therapeutic effect remains unclear. The present study aimed to investigate the potential pharmacological mechanisms of anti-arthritic effect of ELP. The main chemical constituents of ELP were analyzed by ultra-performance liquid chromatography quadrupole-time-flight mass spectrometry (UPLC-Q-TOF-MS). Forty-eight male Wistar rats (220 ± 20 g) were randomly divided into six groups: normal group, collagen-induced arthritis (CIA) group, methotrexate group (1.05 mg/kg), ELP groups (115, 230 and 460 mg/kg). CIA rat models were assigned to evaluate the anti-RA activity of ELP by determining the paws swelling, arthritis score, organ coefficients of spleen and thymus, and histopathological analysis of knee joints of synovial tissues. The levels of TNF-α, IL-10, IL-6 and IL-17 in serum were measured by ELISA. In addition, mRNA and protein expression levels associated with JAK2/STAT3 signaling pathway in synovial tissues of CIA rats were detected by qRT-PCR, immunohistochemistry and Western blot analyses. Fourteen main chemical constituents of ELP were quantitatively determined by UPLC-Q-TOF-MS analysis. Treatment with ELP reduced the paw swelling, arthritis score and organ coefficients of spleen and thymus. Histopathological examination revealed the protective effects of ELP on CIA rats with knee joint injury. The levels of serum pro-inflammatory cytokines (TNF-α, IL-6 and IL-17) were markedly reduced while the anti-inflammatory cytokine IL-10 was significantly increased with the treatment of ELP. Further investigations showed ELP down-regulated the mRNA and protein expression levels of Bcl-2, whereas up-regulated Bax, SOCS1 and SOCS3. Meanwhile, the ratios of p-JAK2/JAK2 and p-STAT3/STAT3 proteins from synovial tissues were dramatically decreased with the treatment of ELP, whereas no changes of the mRNA and protein expression levels of JAK2 and STAT3 were observed. These results indicated that ELP reduced the severity of arthritis and joint swelling, suggesting an antirheumatic effect on CIA rats. The possible mechanism is related to inhibiting inflammatory response and inducing apoptosis in synovial tissues by regulating JAK2/STAT3 signaling pathway. However, further in vivo and in vitro investigations are still needed to clarify the underlying mechanism of ELP in treating RA. Image 1 [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic inflammatory disease due to immune dysregulation that cannot be cured. The skin conditions of psoriasis negatively impact patients' quality of life worldwide. Qing Dai (Indigo Naturalis), a traditional Chinese medicine (TCM) processed from Strobilanthes cusia is a clinical medicine used for psoriasis patient in Taiwan and the gene overexpression of interleukin (IL)-17A could be notably reduced in skin lesions after using Qing Dai ointment and its alkaloid ingredients. To develop a potential anti-psoriatic phytopharmaceutical, an alkaloid-rich fraction named INM-A was prepared from Qing Dai. The chemical profile and anti-psoriatic activity of INM-A were analyzed and evaluated to define its in vitro mechanism and in vivo efficacy for psoriasis therapy. Dowex® 50WX4 hydrogen form resin was used for column chromatography to prepare INM-A. To track alkaloids, INM-A was conducted with Dragendorff's, Mayer's, and Wagner's reagents. HPLC and UV–Vis spectrophotometer were applied to analyze the chemical profile and relative total alkaloid content in INM-A. A psoriatic mouse model induced by imiquimod (IMQ) was performed to verify in vivo efficacy of INM-A. IL-17A-dominated cellular oxygen consumption rate, oxidative stress, and cytokines in keratinocytes were measured to clarify in vitro mechanism of INM-A. An alkaloid-rich fraction, INM-A, consisted of seven active alkaloid compounds 1 – 7 was obtained from Qing Dai. INM-A improved the skin condition severities in IMQ-induced psoriatic mice and decreased IL-17A in not only psoriatic mice but also polarized Th17 cells. In addition, INM-A targeted IL-17A to inhibit inflammation and OXPHOS-driven oxidative stress in human keratinocytes. Accordingly, INM-A manufactured from Qing Dai may be a promising lead phytopharmaceutical for further IL-17A-related inflammatory disease studies such as psoriasis. [Display omitted] • An alkaloid-rich phytopharmaceutical (INM-A) was prepared from Qing Dai. • INM-A could alleviate the severities of dermatitis in IMQ-induced psoriatic mice. • INM-A could decrease IL-17A productions in psoriatic mice and polarized Th17 cells. • INM-A targeted IL-17A to inhibit inflammation (IL-6 and IL-8) in HaCaT cells. • INM-A targeted IL-17A to inhibit OXPHOS-driven oxidative stress in HaCaT cells. [ABSTRACT FROM AUTHOR]