摘要: Objectives Among gynaecologic malignancies, ovarian cancer (OC) represents the leading cause of death for women worldwide. Current OC treatment involves cytoreductive surgery followed by platinum-based chemotherapy, which is associated with severe side effects and development of drug resistance. Therefore, new therapeutic strategies are urgently needed. Herein, we evaluated the anti-tumour effects of Vitamin E-derived delta-tocotrienol (delta-TT) in two human OC cell lines, IGROV-1 and SKOV-3 cells. Materials and Methods MTT and Trypan blue exclusion assays were used to assess delta-TT cytotoxicity, alone or in combination with other molecules. delta-TT effects on cell cycle, apoptosis, ROS generation and MAPK phosphorylation were investigated by flow cytometry, Western blot and immunofluorescence analyses. The synergism between delta-TT and chemotherapy was evaluated by isobologram analysis. Results We demonstrated that delta-TT could induce cell cycle block at G1-S phase and mitochondrial apoptosis in OC cell lines. In particular, we found that the proapoptotic activity of delta-TT correlated with mitochondrial ROS production and subsequent JNK and p38 activation. Finally, we observed that the compound was able to synergize with cisplatin, not only enhancing its cytotoxicity in IGROV-1 and SKOV-3 cells but also re-sensitizing IGROV-1/Pt1 cell line to its anti-tumour effects. Conclusions delta-TT triggers G1 phase cell cycle arrest and ROS/MAPK-mediated apoptosis in OC cells and sensitizes them to platinum treatment, thus representing an interesting option for novel chemopreventive/therapeutic strategies for OC.

摘要: Objectives Previous reports have proposed the importance of signalling and material exchange between cartilage and subchondral bone. However, the specific experimental evidence is still insufficient to support the effect of this interdependent relationship on mutual cell behaviours. In this study, we aimed to investigate cellular lipid metabolism in chondrocytes induced by osteoblasts. Methods Osteoblast-induced chondrocytes were established in a Transwell chamber. A cholesterol detection kit was used to detect cholesterol contents. RNA sequencing and qPCR were performed to assess changes in mRNA expression. Western blot analysis was performed to detect protein expression. Immunofluorescence staining was conducted to show the cellular distribution of proteins. Results Cholesterol levels were significantly decreased in chondrocytes induced by osteoblasts. Osteoblasts reduced cholesterol synthesis in chondrocytes by reducing the expression of a series of synthetases, including Fdft1, Sqle, Lss, Cyp51, Msmo1, Nsdhl, Sc5d, Dhcr24 and Dhcr7. This modulatory process involves Notch1 signalling. The expression of ncstn and hey1, an activator and a specific downstream target of Notch signalling, respectively, were decreased in chondrocytes induced by osteoblasts. Conclusions For the first time, we elucidated that communication with osteoblasts reduces cholesterol synthesis in chondrocytes through Notch1 signalling. This result may provide a better understanding of the effect of subchondral bone signalling on chondrocytes.

摘要: Objectives Necroptosis is widespread in neurodegenerative diseases. Here, we examined necroptosis in the hippocampus and cortex after hydrocephalus and found that a necroptosis pathway inhibitor alleviates necroptosis and provides neuroprotective effects. Materials and methods Hydrocephalus was induced in C57BL/6 mice by kaolin. Haematoxylin and eosin (HE), Nissl, PI and Fluoro-Jade B (FJB) staining were used for general observations. Phosphorylated receptor-interacting protein kinase 3 (p-RIP3) and phosphorylated mixed lineage kinase domain-like (p-MLKL) were measured by Western blotting and immunohistochemistry. Scanning electron microscopy (SEM) was used to observe ependymal cilia. Magnetic resonance imaging (MRI) and the Morris water maze (MWM) test were used to assess neurobehavioral changes. Immunofluorescence was used to detect microglial and astrocyte activation. Inflammatory cytokines were measured by Western blotting and RT-PCR. Results Obvious pathological changes appeared in the hippocampus and cortex after hydrocephalus, and expression of the necroptosis markers p-RIP3, p-MLKL and inflammatory cytokines increased. Necrostatin-1 (Nec-1) and GSK872 reduced necrotic cell death, attenuated p-RIP3 and p-MLKL levels, slightly improved neurobehaviours and inhibited microglial and astrocyte activation and inflammation. Conclusions RIP1/RIP3/MLKL mediates necroptosis in the cortex and hippocampus in a hydrocephalus mouse model, and Nec-1 and GSK872 have some neuroprotective effects.

摘要: Objectives Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons (MN). CREB pathway-mediated inhibition of apoptosis contributes to neuron protection, and PAK4 activates CREB signalling in diverse cell types. This study aimed to investigate PAK4's effect and mechanism of action in ALS. Methods We analysed RNA levels by qRT-PCR, protein levels by immunofluorescence and Western blotting, and apoptosis by flow cytometry and TUNEL staining. Cell transfection was performed for in vitro experiment. Mice were injected intraspinally to evaluate PAK4 function in vivo experiment. Rotarod test was performed to measure motor function. Results The expression and activation of PAK4 significantly decreased in the cell and mouse models of ALS as the disease progressed, which was caused by the negative regulation of miR-9-5p. Silencing of PAK4 increased the apoptosis of MN by inhibiting CREB-mediated neuroprotection, whereas overexpression of PAK4 protected MN from hSOD1(G93A)-induced degeneration by activating CREB signalling. The neuroprotective effect of PAK4 was markedly inhibited by CREB inhibitor. In ALS models, the PAK4/CREB pathway was inhibited, and cell apoptosis increased. In vivo experiments revealed that PAK4 overexpression in the spinal neurons of hSOD1(G93A) mice suppressed MN degeneration, prolonged survival and promoted the CREB pathway. Conclusions PAK4 protects MN from degeneration by activating the anti-apoptotic effects of CREB signalling, suggesting it may be a therapeutic target in ALS.

摘要: Objective As an inhibitor of the AhR signalling pathway, StemRegenin 1 (SR1) not only promotes the expansion of CD34(+) cells but also increases CD34(-) cell numbers. These CD34(-) cells influenced the ex vivo expansion of CD34(+) cells. In this work, the effects of periodically removing CD34(-) cells combined with SR1 addition on the ex vivo expansion and biological functions of HSCs were investigated. Materials and methods CD34(-) cells were removed periodically with SR1 addition to investigate cell subpopulations, cell expansion, biological functions, expanded cell division mode and supernatant TGF-beta 1 contents. Results After 10-day culture, the expansion of CD34(+) cells in the CD34(-) cell removal plus SR1 group was significantly higher than that in the control group and the SR1 group. Moreover, periodically removing CD34(-) cells with SR1 addition improved the biological function of expanded CD34(+) cells and significantly increased the percentage of self-renewal symmetric division of CD34(+) cells. In addition, the concentration of total TGF-beta 1 and activated TGF-beta 1 in the supernatant was significantly lower than those in the control group and the SR1 group. RT-qPCR results showed that the periodic removal of CD34(-) cells with cooperation from SR1 further reduced the expression of AhR-related genes. Conclusions Periodic removal of CD34(-) cells plus cooperation with SR1 improved the expansion of CD34(+) cells, maintained better biological function of expanded CD34(+) cells and reduced the TGF-beta 1 contents by downregulating AhR signalling.