Peptide PD29 treats bleomycin-induced pulmonary fibrosis by inhibiting the TGF-ß/smad signaling pathway.

Pulmonary fibrosis (PF) is an end-stage change in lung disease characterized by fibroblast proliferation, massive extracellular matrix (ECM) aggregation with inflammatory damage, and severe structural deterioration. PD29 is a 29-amino acid peptide which has the potential to alleviate PF pathogenesis via three mechanisms: anti-angiogenesis, inhibition of matrix metalloproteinase activities, and inhibition of integrins. In this study, fibrotic lung injuries were induced in SD rats by a single intratracheal instillation of 5 mg/kg bleomycin (BLM). Then, these rats were administered 7.5, 5, or 2.5 mg/kg PD29 daily for 30 days. BLM induced-syndromes including structure distortion, excessive deposition of ECM, excessive inflammatory infiltration, and pro-inflammatory cytokine release were used to evaluate the protective effect of PD-29. Oxidative stress damage in lung tissues was attenuated by PD29 in a dose-dependent manner. The expression of TGF-ß1 and the phosphorylation of Smad-2/-3-its downstream targets-were enhanced by BLM and weakened by PD29. In vitro, PD29 inhibited TGF-ß1-induced epithelial-mesenchymal transition (EMT) and transformation in A549 cells and mouse primary fibroblasts into myofibroblasts. In summary, PD29 reversed EMT and transformation of fibroblasts into myofibroblasts in vitro and prevented PF in vivo possibly by suppressing the TGF-ß1/Smad pathway.

Treatment Effects of the Second-Generation Tyrosine Kinase Inhibitor Dasatinib on Autoimmune Arthritis.

Rheumatoid arthritis (RA) is a multifactorial autoimmune disease that primarily manifests as persistent synovitis and progressive joint destruction. Imatinib exhibited a therapeutic effect in murine collagen-induced arthritis (CIA) via selective inhibition tyrosine kinases. The second-generation tyrosine kinase inhibitor dasatinib exhibits more durable hematological and cytogenetic effects and more potency compared to imatinib. However, the effect of dasatinib on CIA is poorly understood. The present study investigated the treatment effect of dasatinib on autoimmune arthritis. We demonstrated that dasatinib alleviated arthritis symptoms and histopathological destruction in CIA mice. Dasatinib treatment inhibited the production of proinflammatory cytokines including IL-1ß, TNF-α, and IL-6, and promoted the production of the anti-inflammatory cytokine IL-10. Dasatinib treatment also suppressed the expression of anti-mouse CII antibodies including total IgG, IgG1, IgG2, and IgG2b, in CIA mice. We further demonstrated that dasatinib inhibited the migration and proliferation of fibroblast-like synoviocytes (FLS) from RA patients and promoted FLS apoptosis. The mRNA expression of MMP13, VEGF, FGF, and DKK1 was down-regulated in FLS treated with dasatinib. Our findings suggest that dasatinib exhibited treatment effects on CIA mice and that FLS are an important target cell of dasatinib treatment in autoimmune arthritis.

Anti-fibrotic effects of Salvia miltiorrhiza and Ligustrazine Injection on LX-2 cells involved with increased N-myc downstream-regulated gene 2 expression.

OBJECTIVE: To investigate the effects of Salvia miltiorrhiza and Ligustrazine Injection (SML) on proliferation and apoptosis of human hepatic stellate cell LX-2 and the expression of N-myc downstreamregulated gene 2 (NDRG2, a tumor suppressor gene). METHODS: HSCs from the LX-2 cell line were cultured in vitro. The proliferative state of different initial LX-2 cell numbers was measured using a 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. LX-2 cells were plated in 96-well plates at an approximate density of 2.50×104 cells/mL and cultured for 24 h followed by the application of different concentrations of SML (1, 2, 4 and 8 µL/mL). Cell proliferation was measured using the MTT assay at 24 and 48 h. Apoptosis was detected by flow cytometry at 24 h. LX-2 cells were treated with different concentrations of SML and extracted with protein lysis buffer. The levels of NDRG2 and ß-catenin were measured by Western blot. RESULTS: With the exception of the 1 and 2 µL/mL concentrations, 4 and 8 µL/mL SML inhibited cell proliferation in a concentration-dependent manner at 24 and 48 h (P<0.05). With the exception of the 1 and 2 µL/mL concentrations, the NDRG2 expression level was greatly increased in a concentration-dependent manner. However, the level of ß-catenin was unaffected. CONCLUSION: SML inhibit LX-2 cell proliferation in a concentration-dependent manner, and the mechanism may be associated with NDRG2 over-expression.