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Background and Purpose: Celastrol exhibits anti-arthritic effects in rheumatoid arthritis (RA), but the role of celastrol-mediated Ca2+ mobilization in treatment of RA remains undefined. Here, we describe a regulatory role for celastrol-induced Ca2+ signalling in synovial fibroblasts of RA patients and adjuvant-induced arthritis (AIA) in rats.Experimental Approach: We used computational docking, Ca2+ dynamics and functional assays to study the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase pump (SERCA). In rheumatoid arthritis synovial fibroblasts (RASFs)/rheumatoid arthritis fibroblast-like synoviocytes (RAFLS), mechanisms of Ca2+ -mediated autophagy were analysed by histological, immunohistochemical and flow cytometric techniques. Anti-arthritic effects of celastrol, autophagy induction, and growth rate of synovial fibroblasts in AIA rats were monitored by microCT and immunofluorescence staining. mRNA from joint tissues of AIA rats was isolated for transcriptional analysis of inflammatory genes, using siRNA methods to study calmodulin, calpains, and calcineurin.Key Results: Celastrol inhibited SERCA to induce autophagy-dependent cytotoxicity in RASFs/RAFLS via Ca2+ /calmodulin-dependent kinase kinase-β-AMP-activated protein kinase-mTOR pathway and repressed arthritis symptoms in AIA rats. BAPTA/AM hampered the in vitro and in vivo effectiveness of celastrol. Inflammatory- and autoimmunity-associated genes down-regulated by celastrol in joint tissues of AIA rat were restored by BAPTA/AM. Knockdown of calmodulin, calpains, and calcineurin in RAFLS confirmed the role of Ca2+ in celastrol-regulated gene expression.Conclusion and Implications: Celastrol triggered Ca2+ signalling to induce autophagic cell death in RASFs/RAFLS and ameliorated arthritis in AIA rats mediated by calcium-dependent/-binding proteins facilitating the exploitation of anti-arthritic drugs based on manipulation of Ca2+ signalling. [ABSTRACT FROM AUTHOR]

Background: Relapse was the major cause of treatment failure in patients with myeloid malignancies after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Patients who still suffer from the disease while cannot be detected by morphological analysis can be identified by the minimal residual disease (MRD) monitoring. The most used first-line regimens for MRD are immunotherapies. However, for patients who were ineligible for or failed in first-line immunotherapies, options were limited., Methods: A total of 20 patients with myeloid malignancies with recurrent MRD after allo-HSCT were included in this study. The safety and efficacy of venetoclax-based regimens were analyzed., Results: There were 13 patients (65%) treated with venetoclax combined with hypomethylating agents concomitantly and seven patients (35%) treated with venetoclax monotherapy. After venetoclax-based regimens, MRD was eliminated in 11 patients (55%) with 6 subsequently developing recurrent MRD and 5 remaining in molecular remission. MRD declined in two patients (10%), and no responses in seven patients (35%). Among the two patients with declined MRD, one patient finally eliminated MRD after two cycles of the venetoclax-based regimen, and the other patient's MRD further declined after the second regimen. The objective response rate (ORR) was 65%. The median duration of response was 103 (12-313) days. The incidences of grades 3-4 neutropenia, anemia, and thrombocytopenia independently of pretreatment status were 30%, 20% and 20%, respectively., Conclusion: Venetoclax-based regimens are efficient and safe for MRD in patients with myeloid malignancies ineligible for or failed in the first-line immunotherapies after allo-HSCT.

While the detailed mechanisms for how particulate matter (PM) causes adverse health effects in the lungs remain largely unknown, endoplasmic reticulum (ER) stress has been implicated in PM-induced lung injury. The present study was undertaken to examine how/if ER stress might regulate PM-induced inflammation, and to begin to define potential underlying molecular mechanisms. Here, ER stress hallmarks were examined in human bronchial epithelial (HBE) cells exposed to PM. To confirm roles of certain pathways, siRNA targeting ER stress genes and an ER stress inhibitor were employed. Expression of select inflammatory cytokines and related signaling pathway components by the cells were assessed as well. The results showed that PM exposure induced elevations in two ER stress hallmarks, i.e. GRP78 and IRE1α, in time-and/or dose-related manners in the HBE cells. Inhibition of ER stress by siRNA for GRP78 or IRE1α significantly alleviated the PM-induced effects. Further, ER stress appeared to regulate PM-induced inflammation - likely through downstream autophagy and NF-κB pathways - as implied by studies showing that inhibition of ER stress by siRNA of GRP78 or IRE1α caused significant amelioration of PM-induced autophagy and subsequent activation of NF-κB pathways. Moreover, the ER stress inhibitor 4-PBA were used to confirm the protective effects against PM-induced outcomes. Together, the results suggest ER stress plays a deleterious role in PM-induced airway inflammation, possibly through activation of autophagy and NF-κB signaling. Accordingly, protocols/treatments that could lead to inhibited ER stress could potentially be effective for treatment of PM-related airway disorders.

In the complex cation of the title salt, [Cu(C(12)H(10)N(6))(2)(C(8)H(6)O(4))(2)](C(8)H(5)O(4))(2), the Cu(II) atom, lying on an inversion center, exhibits a distorted octa-hedral geometry defined by four N atoms from two 4-amino-3,5-bis-(pyridin-2-yl)-4H-1,2,4-triazole ligands in the equatorial plane and two axial O atoms from two benzene-1,2-dicarb-oxy-lic acid ligands. In the crystal, the complex cations and the monodeprotonated 2-carb-oxy-benzoate anions are connected by O-H⋯O and N-H⋯O hydrogen bonds, forming a tape along [100]. Adjacent tapes are further linked into a three-dimensional arrangement via π-π stacking inter-actions between the triazole and benzene rings and between the pyridine and benzene rings [centroid-centroid distances = 3.6734 (14)/3.9430 (16) and 3.8221 (14) Å]. Intra-molecular N-H⋯N and O-H⋯O hydrogen bonds are also observed.