Estrogen Regulation of the Expression of Pain Factor NGF in Rat Chondrocytes.

OBJECTIVE: Pain is the main symptom of osteoarthritis (OA). Nerve growth factor (NGF) plays a crucial role in the generation of OA pain. And estrogen-alone used resulted in a sustained joint pain reduction in postmenopausal women. So we aim to find whether estrogen alters chondrocytes' NGF level, affecting OA pain. METHODS: Primary chondrocytes and cartilage explants isolated from Sprague Dawley rat knees were cultured with physiological concentrations of estrogen (17ß-Estradiol ≥ 98%, E2), Estrogen Receptor α (ERα) inhibitor and stimulants. Then, chondrocytes NGF mRNA expression and protein release were analyzed by a quantitative real-time polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) respectively. Additionally, cultures were pre-incubated with MEK-ERK inhibitor to identify the signaling pathway that estrogen alters NGF mRNA and protein levels. RESULTS: We found that chondrocytes NGF expression and release were decreased by E2. E2 also reduced chondrocytes IL-1ß-stimulated or TGF-ß1-stimulated NGF expression. Phosphorylated extracellular signal-regulated kinasep1/2 (p-ERK1/2) signals were detected stronger than the control group by Western Blotting (WB). When we cultured chondrocytes with PD98059 (MEK-ERK inhibitor, PD), NGF mRNA expression was added to 1.41Ct (2.07±0.1 fold). CONCLUSION: We showed that E2 reduces chondrocytes NGF expression significantly, even after stimulation by TGF-ß1 or IL-1ß. MEK-ERK signaling is involved in this process.

Correlation between three-dimensional medial longitudinal arch joint complex mobility and medial arch angle in stage II posterior tibial tendon dysfunction.

BACKGROUND: The purpose of this study was to evaluate correlation between three-dimensional medial longitudinal arch joint complex mobility and medial arch angle in stage II posterior tibial tendon dysfunction flatfoot under loading. METHODS: CT scans of 15 healthy feet and 15 feet with stage II posterior tibial tendon dysfunction flatfoot were taken both in non- and simulated weight-bearing condition. The CT images of the hindfoot and medial longitudinal arch bones were reconstructed into three-dimensional models with Mimics and Geomagic reverse engineering software. The three-dimensional complex mobility of each joint in the medial longitudinal arch and their correlation with the medial arch angle change were calculated. RESULTS: From non- to simulated weight-bearing condition, the medial arch angle change and the medial longitudinal arch joints mobility were significant larger in stage II posterior tibial tendon dysfunction flatfoot (p<0.05). The eversion of the talocalcaneal joint, the proximal translation of the calcaneus relative to the talus, the dorsiflexion of the talonavicular joint, the dorsiflexion and abduction of the medial cuneonavicular joint, and the lateral translation of the medial cuneiform relative to the navicular, and the dorsiflexion of the first tarsometatarsal joint were all significantly correlated to the medial arch angle change in stage II posterior tibial tendon dysfunction flatfoot (all r>0.5, p<0.05). CONCLUSIONS: There is increased mobility in the medial longitudinal arch joints in stage II posterior tibial tendon dysfunction flatfoot and the medial arch angle change under loading causes displacement not only at hindfoot joints but also involve midfoot and forefoot joint.

Injection of synthetic mesenchymal stem cell mitigates osteoporosis in rats after ovariectomy.

Osteoporosis is a severe skeletal disorder. Patients have a low bone mineral density and bone structural deterioration. Mounting lines of evidence suggest that inappropriate apoptosis of osteoblasts/osteocytes leads to maladaptive bone remodelling in osteoporosis. It has been suggested that transplantation of stem cells, including mesenchymal stem cells, may alter the trajectory of bone remoulding and mitigate osteoporosis in animal models. However, stem cells needed to be carefully stored and characterized before usage. In addition, there is great batch-to-batch variation in stem cell production. Here, we fabricated therapeutic polymer microparticles from the secretome and membranes of mesenchymal stem cells (MSCs). These synthetic MSCs contain growth factors secreted by MSCs. In addition, these particles display MSC surface molecules. In vitro, co-culture with synthetic MSCs increases the viability of osteoblast cells. In a rat model of ovariectomy-induced osteoporosis, injection of synthetic MSCs mitigated osteoporosis by reducing cell apoptosis and systemic inflammation, but increasing osteoblast numbers. Synthetic MSC offers a promising therapy to manage osteoporosis.

Acamprosate Protects Against Adjuvant-Induced Arthritis in Rats via Blocking the ERK/MAPK and NF-κB Signaling Pathway.

Osteoarthritis is a type of joint disease that results from the breakdown of joint cartilage and underlying bone and is believed to be caused by mechanical stress on the joint and low-grade inflammatory processes. Acamprosate significantly ameliorates the pathological features of experimental autoimmune encephalomyelitis due to its anti-inflammatory effect. The aims of the present study were to investigate the anti-arthritis activities of acamprosate and elucidate the underlying mechanisms. Adjuvant-induced arthritis (AIA) was induced by intradermal injection of complete Freund's adjuvant. Male Wistar rats were randomly divided into five groups: (1) sham control group, (2) AIA group, (3) acamprosate 10 mg/kg (AIA + ACA10), (4) acamprosate 30 mg/kg (AIA + ACA30), and (5) acamprosate 100 mg/kg (AIA + ACA100). Paw swelling and the arthritis index were measured, and the production of IL-1ß, IL-6, and TNF-α was detected by ELISA in serum. The expression of inflammation-related molecules, including c-Raf, ERK1/2, and NF-κB, was determined by Western blotting. We found that acamprosate significantly suppressed paw swelling and the arthritis index in AIA rats. Moreover, acamprosate also significantly suppressed the production of TNF-α, IL-1ß, and IL-6 in serum, which is elevated by AIA induction. Finally, acamprosate inhibited p-c-Raf and p-ERK1/2 and NF-κB activation after AIA treatment. These results indicate that acamprosate has an anti-inflammatory effect on adjuvant-induced arthritic rats via inhibiting the ERK/MAPK and NF-κB signaling pathways, and acamprosate may serve as a promising novel therapeutic agent for osteoarthritis.

Arthroscopic Rotator Cuff Repair With Graft Augmentation of 3-Dimensional Biological Collagen for Moderate to Large Tears: A Randomized Controlled Study.

BACKGROUND: Due to the highly organized tissue and avascular nature of the rotator cuff, rotator cuff tears have limited ability to heal after the tendon is reinserted directly on the greater tubercle of the humerus. Consequently, retears are among the most common complications after rotator cuff repair. Augmentation of rotator cuff repairs with patches has been an active area of research in recent years to reduce retear rate. HYPOTHESIS: Graft augmentation with 3D collagen could prevent retears of the repaired tendon and improve tendon-bone healing in moderate to large rotator cuff tears. STUDY DESIGN: Randomized controlled study; Level of evidence, 2. METHODS: A prospective, randomized controlled study was performed in a consecutive series of 112 patients age 50 to 85 years who underwent rotator cuff repair with the suture-bridge technique (58 patients, control group) or the suture-bridge technique augmented with 3-dimensional (3D) collagen (54 patients, study group). All patients were followed for 28.2 months (range, 24-36 months). Visual analog scale score for pain, University of California Los Angeles (UCLA) shoulder score, and Constant score were determined. Magnetic resonance imaging was performed pre- and postoperatively (at a minimum of 24 months) to evaluate the integrity of the rotator cuff and the retear rate of the repaired tendon. Three patients in each group had biopsies at nearly 24 months after surgery with histological assessment and transmission electron microscopy. RESULTS: A total of 104 patients completed the final follow-up. At the 12-month follow-up, the UCLA shoulder score was 28.1 ± 1.9 in the study group, which was significantly better than that in the control group (26.9 ± 2.1, P = .002). The Constant score was also significantly better in the study group (87.1 ± 3.2) than in the control group (84.9 ± 4.2, P = .003). However, at the final follow-up, no significant differences were found in the UCLA shoulder scores (29.4 ± 1.9 in the control group and 30.0 ± 1.6 in the study group, P = .052) or Constant scores (89.9 ± 3.2 in the control group and 90.8 ± 3.5 in the study group, P = .18). In terms of structural integrity, more patients in the study group had a favorable type I retear grade (18/51) than in the control group (10/53) ( P = .06). The postoperative retear rate was 34.0% in the control group and 13.7% in the study group, thus indicating a significantly lower retear rate in the study group ( P = .02). Biopsy specimens of the tendon-bone interface in 6 patients revealed more bone formation and more aligned fibers with larger diameters in the study group than in the control group. No intraoperative or postoperative complications were noted in either group. CONCLUSION: 3D collagen augmentation could provide effective treatment of moderate to large rotator cuff tears, providing substantial functional improvement, and could reduce the retear rate. This technique could also promote new tendon-bone formation, thus exerting a prominent effect on tendon-bone healing.

MiR-136 controls neurocytes apoptosis by regulating Tissue Inhibitor of Metalloproteinases-3 in spinal cord ischemic injury.

BACKGROUND: Spinal cord ischemia is a serious injury that threatens human health and life. Furthermore, it was widely accepted that miR-136 was mediated in the spinal injury, while whether it regulated neurocytes apoptosis in I/R-induced spinal cord injury remains unclear. METHODS: Spinal cord ischemia injury (SCII) rats were induced by clamping the nontraumatic vascular clip on the abdominal aorta. Real-time PCR was conducted to determine the mRNA expression, and western blot was carried out to measure protein expression. TUNEL assay was used to measure cell apoptosis. RESULTS: MiR-136 was up-regulated, while Tissue Inhibitor of Metalloproteinases-3 (TIMP3) was down-regulated in both SCII rats and hypoxic neurocytes. MiR-136 overexpression protected neurocytes against injury that induced by hypoxia. TIMP3 was the target gene of miR-136. Hypoxia supplementation decreased the expression of miR-136, promoted TIMP3 expression, and urged cell apoptosis, cells transfected with miR-136 mimic reversed the effect that induced by hypoxia, while cells co-transfected with pcDNA-TIMP3 abolished the results that induced by overexpressed miR-136. CONCLUSION: MiR-136 regulated neurocytes apoptosis of SCII by mediating TIMP3.

Adipose-Derived Stem Cells Suppress Inflammation Induced by IL-1ß through Down-Regulation of P2X7R Mediated by miR-373 in Chondrocytes of Osteoarthritis.

Adipose-derived stem cells (ADSCs) were previously considered to have an anti-inflammatory effect, and Interleukin-1ß (IL-1ß) was found to be a pro-inflammatory factor in chondrocytes, but the mechanism underlying ADSCs and IL-1ß is unclear. In this study, we investigate whether P2X7 receptor (P2X7R) signalling, regulated by microRNA 373 (miR-373), was involved in the ADSCs and IL-1ß mediated inflammation in osteoarthritis (OA). Chondrocytes were collected from 20 OA patients and 20 control participants, and ADSCs were collected from patients who had undergone abdominal surgery. The typical surface molecules of ASDCs were detected by flow cytometry. The level of nitric oxide (NO) was determined by Griess reagent. Concentrations of prostaglandin E2 (PGE2), interleukin 6 (IL-6), matrix metallopeptidase 3 (MMP-3) were detected by enzyme-linked immunosorbent assay (ELISA). The expressions of IL-6, MMP-3, miR-373 and P2X7R were determined by real-time polymerase chain reaction (PCR), and Western blot was used to detect the protein expression of P2X7R. The typical potential characters of ADSCs were verified. In chondrocytes or OA tissues, the miR-373 expression level was decreased, but the P2X7R expression was increased. IL-1ß stimulation increased the level of inflammatory factors in OA chondrocytes, and ADSCs co-cultured with IL-1ß-stimulated chondrocytes decreased the inflammation. OA chondrocytes transfected with the miR-373 inhibitor increased the inflammation level. The miR-373 mimic suppressed the inflammation by targeting P2X7R and regulated its expression, while its effect was reversed by overexpression of P2X7R. IL-1ß induced inflammation in OA chondrocytes, while ADSCs seemed to inhibit the expression of P2X7R that was regulated by miR-373 and involved in the anti-inflammatory process in OA.

Expression and purification of FGF21 in Pichia pastoris and its effect on fibroblast-cell migration.

Fibroblast growth factor (FGF)21 functions in the maintenance of glucose homeostasis and exerts protective effects on the liver, heat and kidneys. However, the roles of FGF21 in other tissue types are yet to be fully elucidated. The present study detected elevated expression levels of FGF21 in skin tissue. Furthermore, it was revealed that FGF21 expression in the skin was induced upon wounding. In addition, ß­klotho expression was detected in the skin tissue. To examine the role of FGF21 in the wound healing process, recombinant human (h)FGF21 was expressed in a the yeast strain Pichia (P.) pastoris, a well­known system for recombinant protein production. Based on the sequence of hFGF21 and the optimal codon of P. pastoris, codon­optimized FGF21 open reading frame sequences were obtained using seven pairs of 55­59­nt primers with seven rounds of PCR. The recombinant FGF21 was purified and its function was examined in human fibroblast cells using a wound healing cell migration assay. Treatment with FGF21 promoted cell migration, which is an important step in wound healing. Furthermore, FGF21 treatment enhanced the activity of c­Jun N­terminal kinase, a key regulator in fibroblast­cell migration. In conclusion, FGF21 is induced after wounding and FGF21 expressed and purified from yeast markedly accelerates wound healing. The present study was the first to elucidate the function of FGF21 in skin tissues and provided a theoretical basis for the use of FGF21 in the treatment of skin wounds.

Clinical significance of microRNA-130b in osteosarcoma and in cell growth and invasion.

OBJECTIVE: To investigate clinical significance of microRNA-130b (miR-130b) in osteosarcoma and its role in cell growth and invasion. METHODS: miR-130b expression was detected in 68 samples of surgically resected osteosarcoma and matched normal tumor-adjacent tissues by qRT-PCR. The expression of miR-130b was altered by corresponding vectors in osteosarcoma cells, and then Western blot was used to detect the expression of PPARγ. BrdU cell proliferation and Transwell assays were performed to determine cell proliferation and invasion. RESULTS: The expression of miR-130b in osteosarcoma tissues was significantly higher than that in normal tumor-adjacent tissues. Its expression in patients with metastasis was significantly higher than that in those without metastases. miR-130b expression in tumor tissues was significantly associated with tumor size, clinical stage and distant metastasis. And its expression was significantly correlated with overall survival and disease free survival. miR-130b overexpression obviously repressed the expression of PPARγ, and resulted in significant increase of Saos-2 cell proliferation and invasion. On the contrast, repressing miR-130b expression with its inhibitor significantly increased PPARγ expression, and inhibited MG-63 cell proliferation and invasion. CONCLUSIONS: The high-expression of miR-130b is correlated with the adverse clinicopathological features and poor prognosis in osteosarcoma. miR-130b may regulate proliferation and invasion of osteosarcoma cells by targeting PPARγ, suggesting miR-130b may play a key role in the progression of osteosarcoma.

Polymeric immunoglobulin receptor expression is correlated with poor prognosis in patients with osteosarcoma.

The prognosis of patients with osteosarcoma with distant metastasis and local recurrence remains poor. Increased expression of polymeric immunoglobulin receptor (pIgR) in tumor tissue has been detected in various types of cancer. However, the clinical significance of pIgR in osteosarcoma has yet to be elucidated. The present study aimed to investigate the prognostic value of pIgR in patients with osteosarcoma following surgical resection. pIgR expression was assessed using quantitative polymerase chain reaction analysis in cryopreserved osteosarcoma tissues from 22 patients, as well as using immunohistochemistry in paraffin-embedded osteosarcoma tissues from 136 patients. The association between pIgR expression, clinicopathological factors and long-term prognosis was retrospectively examined in these 136 patients. The prognostic significance of negative or positive pIgR expression in osteosarcoma was assessed using Kaplan-Meier survival analysis and log-rank tests. Univariate analysis indicated that patients with positive pIgR osteosarcoma tissue expression had a significantly worse overall survival (OS) compared with patients with negative pIgR osteosarcoma expression. Multivariate analysis revealed that positive pIgR expression in osteosarcoma tissues was an independent prognostic factor for OS following surgical resection (P<0.001). Furthermore, positive pIgR expression was significantly associated with poor prognosis in patients with osteosarcoma. These findings indicate that pIgR may be a novel predictor for poor prognosis in patients with osteosarcoma following surgical resection.

[Migration of PKH26-labeled mesenchymal stem cells in rats with Alzheimer's disease].

OBJECTIVE: To investigate the migration of fluorescent dye PKH26-labeled BM-MSC in the Alzheimer's model rats. METHODS: Normal human bone marrow extracted for isolation of BM-MSC was cultured in vitro. The 5th passaged BM-MSC was labeled with PKH26, and observed under a fluorescence microscope for PKH26 labeling efficiency, and using flow cytometry BM-MSC surface markers was checked. The PKH26 labeled BM-MSC injected into the tail vein of the normal control group and AD animal model group, 14 days after finding the PKH26-labeled BM-MSC cells in the rat hippocampus using fluorescence microscopy. Using the Morris water maze experiment comparison of AD model and BM-MSC transplantation group of spatial learning and memory ability. RESULTS: TFlow cytometry showed BM-MSC surface markers CD73 and CD105 were positive. In vitro, PKH26-labeled rate of BM-MSC was 100 %. The Morris water maze experiment comparison of BM-MSC transplantation group and AD group of animals, BM-MSC transplantation group at 13, 14 days of spatial learning and memory ability than AD animal group had significantly improved. 14 days after BM-MSCs in rat hippocampus could be found which were PKH26-positive, consistent with DAPI staining. PKH26-positive cells in animal models of AD were significantly more than those in the normal control group. CONCLUSION: BM-MSC in AD rats not only migrates through the blood-brain barrier, but also mainly survives in the hippocampus of AD rats, and it can improve AD rat model of learning disabilities.