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Atractylenolide‐III (AT‐III) is well known as its role in antioxidant and anti‐inflammatory. Present study was aimed to figure out its effects on osteoarthritis and potential mechanisms. Rat model, human osteoarthritis cartilage explants as well as rat/human chondrocyte cultures were prepared to test AT‐III's effects on osteoarthritis progression and chondrocyte senescence. Potential targeted molecules of AT‐III were predicted using network pharmacology and molecular docking, assessed by Western blotting and then verified with rescue experiments. AT‐III treatment alleviated osteoarthritis severity (shown by OARSI grading score and micro‐CT) and chondrocyte senescence (indexed by levels of SA‐β‐gal, P16, P53, MMP13, ROS and ratio of healthy/collapsed mitochondrial membrane potentials). Network pharmacology and molecular docking suggested that AT‐III might play role through NF‐κB pathway. Further experiments revealed that AT‐III reduced phosphorylation of IKKα/β, IκBα and P65 in NF‐κB pathway. As well as nuclear translocation of p65. Both in vivo and in vitro experiments indicated that AT‐III's effects on osteoarthritis and anti‐senescence were reversed by an NF‐κB agonist. AT‐III could alleviate osteoarthritis by inhibiting chondrocyte senescence through NF‐κB pathway, which indicated that AT‐III is a prospective drug for osteoarthritis treatment. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the roles and underlying mechanisms of YAP in the proliferation of neuroblastoma cells. Methods: The expression level of YAP was evaluated by Western blotting and immunocytochemistry. Cell viability, cell proliferation and growth were detected by CCK‐8, PH3 and Ki67 immunostaining, and the real‐time cell analyser system. The nuclear and cytoplasmic proteins of p27Kip1 were dissociated by the nuclear‐cytosol extraction kit and were detected by Western blotting and immunocytochemistry. mRNA levels of Akt, CDK5 and CRM1 were determined by qRT‐PCR. Results: YAP was enriched in SH‐SY5Y cells (a human neuroblastoma cell line). Knock‐down of YAP in SH‐SY5Y cells or SK‐N‐SH cell line (another human neuroblastoma cell line) significantly decreased cell viability, inhibited cell proliferation and growth. Mechanistically, knock‐down of YAP increased the nuclear location of p27Kip1, whereas serum‐induced YAP activation decreased the nuclear location of p27Kip1 and was required for cell proliferation. Meanwhile, overexpression of YAP in these serum‐starved SH‐SY5Y cells decreased the nuclear location of p27Kip1, promoted cell proliferation and overexpression of p27Kip1 in YAP‐activated cells inhibited cell proliferation. Furthermore, knock‐down of YAP reduced Akt mRNA and protein levels. Overexpression of Akt in YAP‐downregulated cells decreased the nuclear location of p27Kip1 and accelerated the proliferation of SH‐SY5Y cells. Conclusions: Our studies suggest that YAP promotes the proliferation of neuroblastoma cells through negatively controlling the nuclear location of p27Kip1 mediated by Akt. [ABSTRACT FROM AUTHOR]

Abstract Olfactory ensheathing cells (OECs) migrate from olfactory epithelium towards olfactory bulb (OB), contributing to formation of the presumptive olfactory nerve layer during development. However, it remains unclear that molecular mechanism of regulation of OEC migration in OB. In the present study, we found that OECs highly expressed the receptors of semaphorin 3A (Sema3A) in vitro and in vivo , whereas Sema3A displayed a gradient expression pattern with higher in inner layer of OB and lower in outer layer of OB. Furthermore, the collapse assays, Boyden chamber migration assays and single-cell migration assays showed that Sema3A induced the collapse of leading front of OECs and inhibited OEC migration. Thirdly, the leading front of OECs exhibited adaptation in a protein synthesis-independent manner, and endocytosis-dependent manner during Sema3A-induced OEC migration. Finally, Sema3A-induced collapse of leading front was required the decrease of focal adhesion and a retrograde F-actin flow in a cofilin activation-dependent manner. Taken together, these results demonstrate that Sema3A as an inhibitive migratory factor for OEC migration through cofilin activation is involved in the formation of olfactory nerve layer. Highlights • Sema3A induces the collapse of OECs and inhibited OEC migration. • OECs exhibit adaptation induced by Sema3A in an endocytosis-dependent manner. • A retrograde F-actin flow by cofilin activation is required for Sema3A-induced collapse in OECs. [ABSTRACT FROM AUTHOR]

Axonal degeneration is a common pathological feature in many acute and chronic neurological diseases such as spinal cord injury (SCI). SARM1 (sterile alpha and TIR motif-containing 1), the fifth TLR (Toll-like receptor) adaptor, has diverse functions in the immune and nervous systems, and recently has been identified as a key mediator of Wallerian degeneration (WD). However, the detailed functions of SARM1 after SCI still remain unclear. Methods: Modified Allen's method was used to establish a contusion model of SCI in mice. Furthermore, to address the function of SARM1 after SCI, conditional knockout (CKO) mice in the central nervous system (CNS), SARM1 Nestin -CKO mice, and SARM1 GFAP -CKO mice were successfully generated by Nestin-Cre and GFAP-Cre transgenic mice crossed with SARM1 flox/flox mice, respectively. Immunostaining, Hematoxylin-Eosin (HE) staining, Nissl staining and behavioral test assays such as footprint and Basso Mouse Scale (BMS) scoring were used to examine the roles of SARM1 pathway in SCI based on these conditional knockout mice. Drugs such as FK866, an inhibitor of SARM1, and apoptozole, an inhibitor of heat shock protein 70 (HSP70), were used to further explore the molecular mechanism of SARM1 in neural regeneration after SCI. Results: We found that SARM1 was upregulated in neurons and astrocytes at early stage after SCI. SARM1 Nestin -CKO and SARM1 GFAP -CKO mice displayed normal development of the spinal cords and motor function. Interestingly, conditional deletion of SARM1 in neurons and astrocytes promoted the functional recovery of behavior performance after SCI. Mechanistically, conditional deletion of SARM1 in neurons and astrocytes promoted neuronal regeneration at intermediate phase after SCI, and reduced neuroinflammation at SCI early phase through downregulation of NF-κB signaling after SCI, which may be due to upregulation of HSP70. Finally, FK866, an inhibitor of SARM1, reduced the neuroinflammation and promoted the neuronal regeneration after SCI. Conclusion: Our results indicate that SARM1-mediated prodegenerative pathway and neuroinflammation promotes the pathological progress of SCI and anti-SARM1 therapeutics are viable and promising approaches for preserving neuronal function after SCI., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Glioma is currently the most widespread and malignant primary intracranial tumor, which is characterized by high heterogeneity and high fatality rates. β-elemene, which is a bioactive compound extracted from a Chinese herb, Curcuma wenyujin, has been reported to reduce resistance of chemotherapeutic drugs and induce apoptosis in tumor cells. However, the role and mechanisms of β-elemene in glioma senescence remains unknown. In the present study, we found that a low concentration of β-elemene (10 μg/mL) induced senescence in glioma cells, including reduction of cell proliferation, hypertrophic morphology, increase of senescence-associated β-galactosidase (SA-β-Gal) activity, upregulation of several senescence-associated genes such as p16, p53 and NF-κB , and downregulation of Lamin B1 . However, a high concentration of β-elemene induced apoptosis in glioma cells. Treatment with β-elemene caused a marked down-regulation of Yes-associated protein (YAP) expression in glioma cells, which is a key transcriptional co-activator in multiple cancers. Moreover, cyclin dependent kinase 6 (CDK6), which is a known downstream target of YAP, was decreased in glioma cells that treated with β-elemene. The overexpression of YAP and CDK6 significantly rescued β-elemene-induced senescence in glioma cells. Finally, β-elemene treatment also induced the senescence of glioma cells in glioma xenograft model through inactivation of YAP-CDK6 pathways, which might inhibit the glioma growth. Taken together, these results reveal a previously unknown role of β-elemene in glioma cell senescence in vitro and in vivo that is associated with YAP-CDK6 signaling pathway, which will enhance our understanding of glioma cell senescence, and provide novel strategies for the treatment of gliomas., Competing Interests: None., (AJCR Copyright © 2021.)

Yes-associated protein (YAP) transcriptional coactivator is negatively regulated by the Hippo pathway and functions in controlling the size of multiple organs, such as liver during development. However, it is not clear whether YAP signaling participates in the process of the formation of glia scars after spinal cord injury (SCI). In this study, we found that YAP was upregulated and activated in astrocytes of C57BL/6 male mice after SCI in a Hippo pathway-dependent manner. Conditional knockout (KO) of yap in astrocytes significantly inhibited astrocytic proliferation, impaired the formation of glial scars, inhibited the axonal regeneration, and impaired the behavioral recovery of C57BL/6 male mice after SCI. Mechanistically, the bFGF was upregulated after SCI and induced the activation of YAP through RhoA pathways, thereby promoting the formation of glial scars. Additionally, YAP promoted bFGF-induced proliferation by negatively controlling nuclear distribution of p27 Kip1 mediated by CRM1. Finally, bFGF or XMU-MP-1 (an inhibitor of Hippo kinase MST1/2 to activate YAP) injection indeed activated YAP signaling and promoted the formation of glial scars and the functional recovery of mice after SCI. These findings suggest that YAP promotes the formation of glial scars and neural regeneration of mice after SCI, and that the bFGF-RhoA-YAP-p27 Kip1 pathway positively regulates astrocytic proliferation after SCI. SIGNIFICANCE STATEMENT Glial scars play critical roles in neuronal regeneration of CNS injury diseases, such as spinal cord injury (SCI). Here, we provide evidence for the function of Yes-associated protein (YAP) in the formation of glial scars after SCI through regulation of astrocyte proliferation. As a downstream of bFGF (which is upregulated after SCI), YAP promotes the proliferation of astrocytes through negatively controlling nuclear distribution of p27 Kip1 mediated by CRM1. Activation of YAP by bFGF or XMU-MP-1 injection promotes the formation of glial scar and the functional recovery of mice after SCI. These results suggest that the bFGF-RhoA-YAP-p27 Kip1 axis for the formation of glial scars may be a potential therapeutic strategy for SCI patients., (Copyright © 2020 the authors.)

Objective: We aimed to investigate the roles and underlying mechanisms of YAP in the proliferation of neuroblastoma cells., Methods: The expression level of YAP was evaluated by Western blotting and immunocytochemistry. Cell viability, cell proliferation and growth were detected by CCK-8, PH3 and Ki67 immunostaining, and the real-time cell analyser system. The nuclear and cytoplasmic proteins of p27 Kip1 were dissociated by the nuclear-cytosol extraction kit and were detected by Western blotting and immunocytochemistry. mRNA levels of Akt, CDK5 and CRM1 were determined by qRT-PCR., Results: YAP was enriched in SH-SY5Y cells (a human neuroblastoma cell line). Knock-down of YAP in SH-SY5Y cells or SK-N-SH cell line (another human neuroblastoma cell line) significantly decreased cell viability, inhibited cell proliferation and growth. Mechanistically, knock-down of YAP increased the nuclear location of p27 Kip1 , whereas serum-induced YAP activation decreased the nuclear location of p27 Kip1 and was required for cell proliferation. Meanwhile, overexpression of YAP in these serum-starved SH-SY5Y cells decreased the nuclear location of p27 Kip1 , promoted cell proliferation and overexpression of p27 Kip1 in YAP-activated cells inhibited cell proliferation. Furthermore, knock-down of YAP reduced Akt mRNA and protein levels. Overexpression of Akt in YAP-downregulated cells decreased the nuclear location of p27 Kip1 and accelerated the proliferation of SH-SY5Y cells., Conclusions: Our studies suggest that YAP promotes the proliferation of neuroblastoma cells through negatively controlling the nuclear location of p27 Kip1 mediated by Akt., (© 2019 The Authors. Cell Proliferation published by John Wiley & Sons Ltd.)