Xiaobin Li

Differential activity of GSK-3 isoforms regulates NF-κB and TRAIL- or TNFα induced apoptosis in pancreatic cancer cells

While TRAIL is a promising anticancer agent due to its ability to selectively induce apoptosis in neoplastic cells, many tumors, including pancreatic ductal adenocarcinoma (PDA), display intrinsic resistance, highlighting the need for TRAIL-sensitizing agents. Here we report that TRAIL-induced apoptosis in PDA cell lines is enhanced by pharmacological inhibition of glycogen synthase kinase-3 (GSK-3) or by shRNA-mediated depletion of either GSK-3α or GSK-3β. In contrast, depletion of GSK-3β, but not GSK-3α, sensitized PDA cell lines to TNFα-induced cell death. Further experiments demonstrated that TNFα-stimulated IκBα phosphorylation and degradation as well as p65 nuclear translocation were normal in GSK-3β-deficient MEFs. Nonetheless, inhibition of GSK-3β function in MEFs or PDA cell lines impaired the expression of the NF-κB target genes Bcl-xL and cIAP2, but not IκBα. Significantly, the expression of Bcl-xL and cIAP2 could be reestablished by expression of GSK-3β targeted to the nucleus but not GSK-3β targeted to the cytoplasm, suggesting that GSK-3β regulates NF-κB function within the nucleus. Consistent with this notion, chromatin immunoprecipitation demonstrated that GSK-3 inhibition resulted in either decreased p65 binding to the promoter of BIR3, which encodes cIAP2, or increased p50 binding as well as recruitment of SIRT1 and HDAC3 to the promoter of BCL2L1, which encodes Bcl-xL. Importantly, depletion of Bcl-xL but not cIAP2, mimicked the sensitizing effect of GSK-3 inhibition on TRAIL-induced apoptosis, whereas Bcl-xL overexpression ameliorated the sensitization by GSK-3 inhibition. These results not only suggest that GSK-3β overexpression and nuclear localization contribute to TNFα and TRAIL resistance via anti-apoptotic NF-κB genes such as Bcl-xL, but also provide a rationale for further exploration of GSK-3 inhibitors combined with TRAIL for the treatment of PDA.

Cryptotanshinone protects against IL-1β-induced inflammation in human osteoarthritis chondrocytes and ameliorates the progression of osteoarthritis in mice.

Abstract Osteoarthritis (OA) is a common degenerative disease characterized by progressive erosion of articular cartilage, subchondral bone sclerosis and synovitis. Cryptotanshinone (CTS), an active component extracted from the root of Salvia miltiorrhiza Bunge, has been shown to have potent anti‐inflammatory effects. However, its effects on OA have not been clearly elucidated. This study aimed to assess the effect of CTS on human OA chondrocytes and mice OA models. Human OA chondrocytes were pretreated with CTS (5, 10 and 20 &mgr;M) for 2 h and subsequently stimulated with IL‐1&bgr; for 24 h. Production of NO, PGE2, IL‐6, TNF‐&agr; was evaluated by the Griess reaction and ELISA. The protein expression of COX‐2, iNOs, MMP‐3, MMP13, COX‐2, ADAMTS‐5, JNK, p‐JNK, ERK, p‐ERK, p38, p‐p38, p‐IKK&agr;/&bgr;, p65, p‐p65, I&kgr;B‐&agr;, and p‐I&kgr;B‐&agr; was tested by Western blot. In vivo, the severity of OA was determined by histological analysis. We found that CTS significantly inhibited the IL‐1&bgr;‐induced production of NO and PGE2; expression of COX‐2, iNOS, MMP‐3, MMP‐13, and ADAMTS‐5. Furthermore, CTS in dramatically suppressed IL‐1&bgr;‐stimulated NF‐&kgr;B and MAPK activation. Immunofluorescence staining demonstrated that CTS could suppress IL‐1&bgr;‐induced phosphorylation of p65 nuclear translocation. In vivo, treatment of CTS prevented the destruction of cartilage and the thickening of subchondral bone in mice OA models. These results indicate that the therapeutic effect of CTS on OA is accomplished through the inhibition of both NF‐&kgr;B and MAPK signaling pathways. Our findings provide the evidence to develop CTS as a potential therapeutic agent f or patients with OA. HighlightsCryptotanshinone inhibited the IL‐1&bgr;‐induced inflammatory mediators in human osteoarthritis chondrocytes.Cryptotanshinone inhibited IL‐1&bgr;‐induced inflammatory response through suppressing NF‐&kgr;B and MAPK activation.Cryptotanshinone alleviated the progression of osteoarthritis in mice models.

Transforaminal lumbar interbody fusion with cortical bone trajectory screws versus traditional pedicle screws fixation: a study protocol of randomised controlled trial

Introduction Transforaminal lumbar interbody fusion (TLIF) has been widely used in the treatment of lumbar degenerative disc disorders and shows favourable clinical results. Recently, cortical bone trajectory (CBT) has become a new trajectory for screw insertion in the lumbar spine. Several biomechanical studies have demonstrated that the CBT technique achieves screw purchase and strength greater than the traditional method. Currently, the available data on the clinical effectiveness of the two performed surgeries, TLIF with CBT screws (CBT-TLIF) and TLIF with traditional pedicle screws (PS-TLIF), are insufficient. This is the first randomised study to compare CBT-TLIF against traditional PS fixation and will provide recommendations for treating patients with lumbar degenerative disc disorders. Methods and analysis A blinded randomised controlled trial (blinding for the patient and statistician, rather than for the clinician and researcher) will be conducted. A total of 254 participants with lumbar disc degenerative disease who are candidates for TLIF surgery will be randomly allocated to either the CBT-TLIF group or the PS-TLIF group at a ratio of 1:1. The primary clinical outcome measures are the incidence of adjacent cranial facet joint violation, fusion rate and the screw loosening rate. Secondary clinical outcome measures are Visual Analogue Scale (VAS) of back pain, VAS of leg pain, Oswestry Disability Index, operative time, intraoperative blood loss and complications. These parameters will be evaluated on day 3, and then at 1, 3, 6, 12 and 24 months postoperatively. Ethics and dissemination This study has been reviewed and approved by the Institutional Review Board of the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University (batch: 2017–03). The results will be presented in peer-reviewed journals and an international spine-related meeting after completion of the study. Trial registration number NCT03105167; Pre-results.

Design of a 3D navigation template to guide the screw trajectory in spine: a step-by-step approach using Mimics and 3-Matic software

Rapid development of 3D printing techniques has led to the design of navigation templates to assist with accurate insertion of pedicle screws in last decades. However, there are still without the precise step-by-step methods to design 3D navigation templates from computed tomography (CT) images. Our present article provides a detailed protocol to allow the readers or researchers to obtain the 3D navigation template easily, and assist with pedicle screw insertion in their future research and surgery. Using 3D navigation template-assisted pedicle screw fixation in spine surgery is low cost and can decrease the radiation exposure to both patients and surgeons.

Normal radiological anatomy of thyroid cartilage in 600 Chinese individuals: implications for anterior cervical spine surgery.

BackgroundThyroid cartilage is an important barrier in anterior cervical approach surgery. The objective of this study is to establish normative values for thyroid cartilage at three planes and to determine their significance on preoperative positioning and intraoperative traction in surgery via the anterior cervical approach.MethodsNeck CT scans were collected from 600 healthy adults who did not meet any of the exclusion criteria. Transverse diameters (D1, D2, and D3) of the superior border of the thyroid cartilage (SBTC), inferior border of the thyroid cartilage (IBTC), and the trachea transverse diameters of the inferior border of the cricoid cartilage (IBCC) were measured on a horizontal plane.ResultsAll measured variables had intra-class correlation coefficients (ICCs) of ≥u20090.7. The differences in transverse diameters on the same plane between males and females were significantly different (all pu2009<xa00.001). The SBTC is most often at C4 in women (59.5%) and C4/5 in men (36.4%), the IBTC is most often at C5 in women (48.1%) and men (46.2%), and the IBCC is primarily located at C6 in women (45.2%) and C6 or C6/7 in men (34.4%) (all pu2009<xa00.001).ConclusionWe present normative values for thyroid cartilage at three planes of SBTC, IBTC, and IBCC in Chinese individuals. The individual and gender differences in the location of the thyroid cartilage and the size of the thyroid cartilage and the cricoid cartilage provide an anatomical basis to localize the skin incision, to predict the difficulty of intraoperative exposure and retractor pulling, and to identify that the thyroid cartilage protected the pharyngoesophageal wall.

Isofraxidin inhibits interleukin-1β induced inflammatory response in human osteoarthritis chondrocytes

ABSTRACT Osteoarthritis (OA) is the most prevalent disease of knee especially in the aged people. Isofraxidin (IF) is a coumarin compound refined from traditional Chinese medicines with potential anti‐inflammatory ability. This study aimed to evaluate protective anti‐inflammatory effects of IF in human OA chondrocytes. The chondrocytes were isolated from OA patients and pretreated with IF before treatment with IL‐1&bgr;. The results showed that IF blocked IL‐1&bgr;‐stimulated production of NO and PGE2. In addition, IF inhibited the expression of COX‐2, iNOs, MMP‐1, MMP‐3, MMP‐13, ADAMTS‐4 and ADAMTS‐5, and increased the levels of aggrecan and collagen‐II. Mechanistically, IF suppressed IL‐1&bgr;‐induced I&kgr;B‐&agr; degradation and NF‐&kgr;B activation. In conclusion, our results demonstrate that IF inhibits inflammation in OA via the regulation of NF‐&kgr;B signaling, and suggest that IF may be a potential therapeutic agent for OA. HighlightsIsofraxidin is a coumarin compound which has not been reported to have effective for treating osteoarthritis.Isofraxidin inhibited the IL‐1&bgr;‐induced inflammatory mediators in human osteoarthritis chondrocytes.Isofraxidin inhibited IL‐1&bgr;‐induced inflammatory response through suppressing NF‐&kgr;B activation

The Protective Effect of Ligustilide in Osteoarthritis: An in Vitro and in Vivo Study

Background/Aims: Osteoarthritis is a degenerative joint disease characterized by cartilage degeneration and a chondrocyte inflammatory response that induces an inflammatory environment closely linked to extracellular matrix (ECM) degradation. Ligustilide (LIG) is a major component of the herb Radix Angelicae Sinensis, with demonstrated anti-inflammatory effects. To confirm whether LIG has an equally inhibitory effect on inflammation in human osteoarthritis chondrocytes, we performed in vivo and in vitro experiments to validate the above conjectures and determine the relevant mechanisms. Methods: Quantitative realtime PCR and western blotting were performed to evaluate the expression of MMP-3, MMP-13, ADAMTS-5, iNOS, and COX-2 at both gene and protein levels. An enzyme-linked immunosorbent assay was used to evaluate the levels of other inflammatory factors (PGE2, TNF-α, and IL-6). The PI3K/AKT and nuclear factor kappa B (NF-κB) signaling pathways were also analyzed by western blotting, whereas immunofluorescence was used to assess the expression of collagen II and aggrecan. The in vitro effect of LIG was evaluated by intraperitoneal injection into a mouse osteoarthritis model induced by destabilization of the medial meniscus. Results: LIG lowered the phosphorylation levels of p65, IκBα, and IKKα/β and suppressed the IL-1β-induced expression of MMP-3, ADAMTS-5, iNOS, and COX-2 and the inflammatory factors PGE2, TNF-α, and IL-6. LIG markedly decreased IL-1β-induced degradation of collagen II and aggrecan. In vivo results showed that LIG-treated mouse cartilage showed less damage than the control group; the Osteoarthritis Research Society International (OARSI) score was also lower. LIG further reduced the thickness of the subchondral bone plate and alleviated the synovitis. Conclusion: LIG may act as a promising therapeutic agent for osteoarthritis by attenuating IL-1β-induced inflammation in chondrocytes and ECM degradation via suppression of NF-κB activation by the PI3K/AKT pathway.

TFEB, a potential therapeutic target for osteoarthritis via autophagy regulation

The blockage of autophagic flux in chondrocytes has been considered as a major reason for the excessive cellular apoptosis and senescence in osteoarthritis (OA) development; however, the molecular mechanism and therapeutic strategy for interrupted autophagic flux is still not clear. Most recently, the transcription factor EB (TFEB) is identified as a master regulator for autophagic flux via initiating the expression of multiple autophagy-related genes and lysosomal biogenesis. This research was performed to confirm whether TFEB expression and activity are impacted in OA development and to confirm the effect of genetic up-regulation of TFEB on autophagic flux and cellular protection in the in vitro and in vivo models of OA. We demonstrated that the expression and nuclear localization of TFEB is decreased in human and mouse OA cartilage as well as in tert-Butyl hydroperoxide (TBHP)-treated chondrocytes. Applying lentivirus to transfect chondrocytes, we found that TFEB overexpression rescues the TBHP-induced the autophagic flux damage, lysosome dysfunction and protects chondrocyte against TBHP induced apoptosis and senescence; these protections of TFEB are diminished by chloroquine-medicated autophagy inhibition. Our destabilized medial meniscus (DMM) mouse OA model shows that TFEB overexpression ameliorates the surgery-induced cartilage degradation, restrains the apoptosis and senescence of chondrocyte, and enhances the autophagic flux. In summary, our study indicates that the activity of TFEB in chondrocyte is involved in OA development, also TFEB overexpression may be a promising strategy for OA treatment.