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Background: Mesenchymal stem cells (MSCs) are under consideration for myocardial ischemia-reperfusion (I/R) injury therapy, but their mechanism remains to be evaluated. In this article, we aimed to study the effects of the miR-29a/follistatin-like 1 axis in bone marrow-derived mesenchymal stem cells on modulating myocyte apoptosis after hypoxia-reoxygenation (H/R) injury., Methods: An in vitro myocardial ischemia-reperfusion injury model of H9c2 cells was developed by hypoxia-reoxygenation injury. The mRNA levels of follistatin-like 1, Bcl-2, Bax, and miR-29a and the protein levels of Bcl-2, Bax, cleaved caspase-3, and components of the JAK2/STAT3 pathway were detected by qRT-PCR and western blotting, respectively. Secretion of follistatin-like 1 was evaluated by enzyme-linked immunosorbent assay. Cell apoptosis was evaluated by flow cytometry. The interaction between miR-29a and follistatin-like 1 was evaluated by dual luciferase reporter assay., Results: MiR-29a suppressed the expression and secretion of follistatin-like 1 in bone marrow-derived mesenchymal stem cells. Overexpression of follistatin-like 1 in bone marrow-derived mesenchymal stem cells decreased apoptosis of myocytes induced by hypoxia-reoxygenation. Cell apoptosis in myocytes was promoted by conditioned medium from bone marrow-derived mesenchymal stem cells with ectopic miR-29a expression. Conditioned medium of miR-29a-overexpressing bone marrow-derived mesenchymal stem cells inhibited the JAK2/STAT3 pathway in myocytes to promote apoptosis of myocytes., Conclusions: MiR-29a in bone marrow-derived mesenchymal stem cells inhibits follistatin-like 1 secretion and promotes myocyte apoptosis by suppressing the JAK2/STAT3 pathway in hypoxia-reoxygenation injury., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Honokiol, a constituent of Magnolia officinalis, has been reported to possess potent anti-cancer activity through targeting multiple signaling pathways in numerous malignancies including acute myeloid leukemia (AML). However, the underlying mechanisms remain to be defined. Here, we report that honokiol effectively decreased enzyme activity of histone deacetylases (HDACs) and reduced the protein expression of class I HDACs in leukemic cells. Moreover, treatment with proteasome inhibitor MG132 prevented honokiol-induced degradation of class I HDACs. Importantly, honokiol increased the levels of p21/waf1 and Bax via triggering acetylation of histone in the regions of p21/waf1 and Bax promoter. Honokiol induced apoptosis, decreased activity of HDACs, and significantly inhibited the clonogenic activity of hematopoietic progenitors in bone marrow mononuclear cells from patients with AML. However, honokiol did not decrease the activity of HDACs and induce apoptosis in normal hematopoietic progenitors from unbilicial cord blood. Finally, honokiol dramatically reduced tumorigenicity in a xenograft leukemia model. Collectively, our findings demonstrate that honokiol has anti-leukemia activity through inhibiting HDACs. Thus, being a relative non-toxic agent, honokiol may serve as a novel natural agent for cancer prevention and therapy in leukemia., (© 2014 Wiley Periodicals, Inc.)

Tetrandrine (Tet), a bisbenzylisoquinoline alkaloid, has been reported to possess anti-tumour activity. However, its effects on human glioma remain unknown. In this study, we demonstrated that Tet inhibited human glioma cell growth in vitro and in vivo . It has been hypothesised that Tet inhibits glioma growth by affecting glioma cell survival, proliferation and vasculature in and around the xenograft tumour in the chick CAM model and signal transducer and activator of transcription 3 (STAT3) mediated these activities. Therefore, we conducted a detailed analysis of the inhibitory effects of Tet on cell survival using a TUNEL assay and flow cytometric analysis; on cell proliferation based on the expression of proliferating cell nuclear antigen; and on angiogenesis using a CAM anti-angiogenesis assay. We used western blotting to investigate the role of STAT3 on the anti-glioma activities of Tet. The results revealed that Tet inhibited survival and proliferation in human glioma cells, impaired tumour angiogenesis and decreased the expression of phosphorylated STAT3 and its downstream proteins. In sum, our data indicate that STAT3 is involved in Tet-induced the regression of glioma growth by activating tumour cell apoptosis, inhibiting glioma cell proliferation and inhibiting angiogenesis. [ABSTRACT FROM AUTHOR]