Departmental sources Background: Osteoporosis is an osteolytic disease resulted from imbalance in bone homeostasis. Studies indicated that N-myc downstream-regulated gene 2 (NDRG2) could affect the osteoclast differentiation. However, the effect of NDRG2 on osteoblastic differentiation and calcification remains unknown. Hence, we aimed to analyze the effect of NDRG2 on the proliferation and differentiation of osteoblasts. Material/Methods: The differentiation of bone morphogenetic protein 2 (BMP2) induced MC3T3-E1 cells was observed by the microscope. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot analysis detected the expression of BMP2, NDRG2, runt-related transcription factor 2 (Runx2), osteoprotegerin (OPG), osterix (OSX), and osteocalcin (OCN). Alkaline phosphatase (ALP) activity assay was detecting the ALP activity and alizarin red staining assay was analyzing intracellular calcium salt deposition. The cell transfection was also verified by RT-qPCR analysis. Results: The results demonstrated that BMP2 promoted the osteoblastic differentiation with the increasing expression of Runx2, OPG, OSX, and OCN. NDRG2 expression was upregulated during osteogenic differentiation. NDRG2 overexpression promoted the expression of Runx2, OPG, OSX, and OCN, and increased the ALP activity while NDRG2 inhibition reversed the changes. NDRG2 overexpression increased the intracellular calcium salt deposition and NDRG2 inhibition reversed the changes. The role of NDRG2 in osteoblastic differentiation and calcification was played through the JAK3/STAT3 signal pathway. Conclusions: The presented data indicated that NDRG2 promoted BMP2-induced osteoblastic differentiation and calcification by activating the JAK3/STAT3 signal pathway.

Morroniside plays a therapeutic role in knee osteoarthritis (OA) by protecting chondrocytes. PI3K/AKT signaling is involved in the regulation of chondrocytes by Morroniside. PI3K/AKT suppresses autophagy through downstream signaling. However, the regulation of chondrocyte autophagy by Morroniside and the significance of the above effect on protecting chondrocytes aren’t clear. The results showed that Morroniside inhibited the autophagiy of human OA chondrocytes. Besides, both PI3K inhibitors and mTOR inhibitors significantly reversed the autophagy reduced by Morroniside, but had no effect on the protective effect of Morroniside on chondrocytes. However, the enhanced autophagy caused by overexpression of autophagic genes enhanced the protective effect of Morroniside on chondrocytes. In conclusion, Morroniside represses the autophagy of human OA chondrocyte, which is related to PI3K/mTOR pathway. Moreover, the upregulation of autophagy further promoted the role of Morroniside in treating chondrocytes. Our data present a potential clue for the therapeutic strategies of Morroniside in treating OA.

Background The partial articular supraspinatus tendon avulsion (PASTA) lesion repair remains a topic of debate. We have performed in situ repair of PASTA lesions using a potentially viable threading lasso fixation technique. This retrospective case series aimed to evaluate the clinical outcomes of PASTA lesion repair using threading lasso fixation. To the best of our knowledge, this is the first study to review this technique and its outcomes in terms of pain and upper extremity function. Methods Twenty-five patients with PASTA lesions who were treated with threading lasso fixation were reviewed. All patients were followed up for at least 1 year. Preoperative and follow-up data were retrospectively collected and reviewed. Clinical outcomes were assessed to evaluate the efficacy of the surgery. Results There were no postoperative complications. The average follow-up period was 25.7 (22–27) months. At the last follow-up, all patients underwent follow-up magnetic resonance imaging; only two cases showed a partially healed tendon and no case converted to full-thickness tear. Furthermore, shoulder pain decreased and mobility was recovered, with statistically significant differences in all scoring measures. Specifically, the mean visual analog scale score decreased from 5.4 ± 1.2 before surgery to 1.1 ± 0.8 at the last follow-up (t = 14.908, P < 0.01), and the mean American Shoulder and Elbow Surgeons Shoulder Assessment Form score improved significantly from 51.6 ± 6.4 to 89.3 ± 5.2 (t = 22.859, P < 0.01). Additionally, the mean University of California Los Angeles score improved from 17.8 ± 3.5 preoperatively to 32.3 ± 1.4 (t = 19.233, P < 0.01). Conclusions Arthroscopic repair using threading lasso fixation is a novel transtendinous technique for patients with partial articular supraspinatus tendon avulsion. Tendon integrity is preserved with this method, which may result in improved function. Overall, threading lasso fixation technique is an effective treatment.