Tangeretin suppresses osteoarthritis progression via the Nrf2/NF-κB and MAPK/NF-κB signaling pathways.

BACKGROUND: Osteoarthritis (OA) is a globally prevalent degenerative disease characterized by extracellular matrix (ECM) degradation and inflammation. Tangeretin is a natural flavonoid that has anti-inflammatory properties. Studies have not explored whether tangeretin modulates OA development. PURPOSE: The aim of this study was to explore the potential effects and mechanism underlying the anti-OA properties of tangeretin. STUDY DESIGN: Effects of tangeretin on OA were detected in chondrocytes and OA mouse model. METHODS: Protective effects of tangeretin on murine articular chondrocytes treated with interleukin-1ß (IL-1ß) were evaluated using qPCR, western blot analysis, ELISA, ROS detection and immunofluorescent staining in vitro. Healing effect of tangeretin on cartilage degradation in mice was assessed through X-ray imaging, histopathological analysis, immunohistochemical staining and immunofluorescent staining in vivo. RESULTS: Tangeretin suppressed IL-1ß-mediated inflammatory mediator secretion and degradation of ECM in chondrocytes. The results showed that tangeretin abrogated destabilized medial meniscus (DMM)-induced cartilage degradation in mice. Mechanistic studies showed that tangeretin suppressed OA development by downregulating activation of NF-κB by activating Nrf2/HO-1 axis and suppressing MAPK signaling pathway. CONCLUSION: Tangeretin abrogates OA progression by inhibiting inflammation as well as ECM degradation in chondrocytes and animal models. Effects of tangeretin are mediated through Nrf2/NF-κB and the MAPK/NF-κB pathways. Thus, tangeretin is a potential therapeutic agent for osteoarthritis treatment.

Percutaneous reduction, cannulated screw fixation and calcium sulfate cement grafting assisted by 3D printing technology in the treatment of calcaneal fractures.

BACKGROUND: Percutaneous reduction, cannulated screw fixation and calcium sulfate cement grafting (PR + CSC) for treatment of displaced and intra-articular calcaneal fractures (DIACFs) is a difficult technique, because the minimally invasive treatment has limited exposure and cannot be used to reduce articular surface under direct vision. The goal of this study was to apply 3D printing technology to preoperative planning and surgery of DIACFs, and to evaluate its effectiveness, feasibility and safety in fracture repair. METHODS: We enrolled 81 patients with DIACFs in the study from August 2015 to August 2017. Patients with DIACFs in our hospital were randomly divided into the 3D printing group (40 cases) and the conventional group (41 cases). The operation duration, blood loss volume and the number of fluoroscopy were compared. Radiological results were evaluated using radiographs and functional results were evaluated using the American Orthopedic Foot and Ankle Society (AOFAS) score. The complications were also assessed. In addition, we made a questionnaire to verify the usefulness of the 3D printed model for both doctors and patients. RESULTS: The operation duration, blood loss volume and the number of fluoroscopy in 3D printing group were significantly less than that in the conventional group. Besides, 3D printing group achieved significantly better radiological results than conventional group both postoperatively and at the final follow-up except the calcaneal width at the final follow-up. The AOFAS score in the 3D printing group was significantly higher than that in the conventional group. In addition, the questionnaire from doctors and patients exhibited high scores of overall satisfaction of the 3D printed models. As for complications, there was no significant difference among the two groups. CONCLUSION: This study suggested the clinical feasibility of PR + CSC assisted by 3D printing technology in the treatment of DIACFs. LEVEL OF EVIDENCE: II.

Hydroxysafflor yellow A promotes multiterritory perforating flap survival: an experimental study.

The use of perforator flaps is a common surgical technique in wound repair. However, the area surrounding the multiterritory perforating flap often becomes necrotic due to ischemia. Hydroxysafflor yellow A (HSYA), a traditional Chinese medicine extracted from edible safflower, can be used medicinally to promote angiogenesis, inhibit apoptosis, and alleviate oxidative stress and other biological activities. Here, we investigated the effect of HSYA on perforator flap survival and its potential mechanism. Our results demonstrate that HSYA significantly improves the survival area of perforator flaps, increases blood supply, reduces tissue edema, and increases mean vascular density. HSYA treatment promotes angiogenesis and inhibits oxidative stress, apoptosis, and autophagy in perforator flaps, suggesting many potential mechanisms for flap survival.

Schisandrin B attenuates epidural fibrosis in postlaminectomy rats by inhibiting proliferation and extracellular matrix production of fibroblasts.

Laminectomy has been widely considered one of the most common treatments for lumbar disorders. Epidural fibrosis (EF) is a common complication after laminectomy, causing recurrent postoperative pain. Schisandrin B (Sch.B), the active ingredient extracted from Schisandra chinensis Fructus, has been found to have potent antiproliferative and antifibrotic effects on several cells. This study aimed to investigate the effects of Sch.B on the prevention of postlaminectomy EF formation. In vitro, we studied the effects of Sch.B on transforming growth factor beta 1 (TGF-ß1)-induced proliferation and extracellular matrix (ECM) production of primary fibroblasts, as well as its underlying mechanism. We found that Sch.B not only inhibited the proliferation of fibroblasts but also reduced ECM production, including that of connective tissue growth factor, fibronectin, and type I collagen, in a dose-dependent manner. Mechanistically, we found that Sch.B suppressed TGF-ß1-stimulated activation of the Smad2/3 and mitogen-activated protein kinase pathways. Moreover, the in vivo study demonstrated that Sch.B treatment attenuated the progression of EF in a postlaminectomy rat model via reducing the cell number and ECM production of scar tissue. Taken together, these data suggested that Sch.B possesses great potential value as a preventative agent for EF.