Electroacupuncture improves motor function of rats with osteoarthritis by alleviating joint inflammation through the Wnt-7B/β-catenin signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effect of electroacupuncture on osteoarthritis in rats and explore the possible mechanism.@*METHODS@#Thirty SD rats were randomly divided into osteoarthritis model group, electro-acupuncture group and control group (n=10), and in the former two groups, early osteoarthritis was induced using a modified DMM surgical modeling method. After successful modeling, the rats in the electro-acupuncture group were treated with electro-acupuncture at bilateral "Housanli" and "Anterior knee point". Behavioral tests of the rats were performed and scored using the LequesneMG scale. Subchondral bone degeneration was observed in each group, and serum levels of IL-1β, ADAMTS-7, MMP-3 and COMP were measured using ELISA. The mRNA and protein expressions of IL-1β, Wnt-7B, β-catenin, ADAMTS-7, and MMP-3 in the cartilage tissue of the knee joints were detected using RT-PCR and Western blotting.@*RESULTS@#In behavioral tests, the rats in the model and electroacupuncture groups had significantly higher LequesneMG scores after modeling than those in the control group (P < 0.05). After 20 days of treatment, LequesneMG scores were significantly lowered in rats in the electroacupuncture as compared with the model rats (P < 0.05). Imaging examination revealed obvious subchondral bone damage in both the electroacupuncture group and the model group, but the damages were significantly milder with former group. Compared with the model rats, the rats receiving electroacupuncture had significantly lower serum levels of IL-1β, ADAMTS-7, MMP-3 and COMP (P < 0.05) with also lower expressions of IL-1β, Wnt-7B, β-catenin, ADAMTS-7 and MMP-3 in the cartilage tissues at both the mRNA and protein levels (P < 0.05).@*CONCLUSION@#Electroacupuncture can alleviate joint pain and improve subchondral bone damage in rats with osteoarthritis by reducing IL-1β levels in the joint cartilage tissue and serum to alleviate joint inflammation and by reducing such cytokines as ADAMTS-7 and MMP-3 via regulating the Wnt-7B/β-catenin signaling pathway.

Experimental study on the regulation of subchondral bone plate osteoprotegerin/receptor activator of nuclear factor kappa-B ligand system by berberine to retard the development of osteoarthritis in rabbits / 中国骨伤

OBJECTIVE@#To investigate the effect of intra-articular berberine injection on the structural remodeling of subchondral bone plate and osteoprotegerin/receptor activator of nuclear factor kappa-B ligand(OPG/RANKL) system expression in rabbits with osteoarthritis(OA).@*METHODS@#Forty 12-month-old male rabbits with an average of(2.73±0.18) kg of body weight, underwent left anterior cruciate ligament transection(ACLT), and were divided into berberine group and placebo groups after operation, 20 rabbits in each group. The berberine group received intra-articular injection of 100 μmol/L berberine 0.3 ml every week for 6 weeks. In placebo group, the same dose of 0.9% sodium chloride injection was injected into the left knee joint cavity every week for 6 weeks. Another 20 12-month-old male rabbits, weighing (2.68±0.18) kg, underwent sham operation on the left knee joint without intra-articular injection intervention (sham operation group). On the last day of the sixth week after operation, three groups of animals were sacrificed to obtain knee joint specimens. The femoral medial condyle samples were obtained for histological evaluation of cartilage and subchondral bone, Mankin scoring system was used to evaluate articular cartilage structure. Image-Pro Plus(IPP) software was used to evaluate subchondral bone plate bone volume(BV), bone volume/total volume(BV/TV), trabecular circumference(TC), mean trabecular thickness (Tb.Th). Real-time quantitative reverse transcription polymerization Enzyme chain reaction(reverse transcription-polymerase chain reaction, RT-PCR) was used to detect the mRNA expression levels of OPG and RANKL in subchondral bone tissue at 6 weeks after operation.@*RESULTS@#The cartilage structure evaluation showed that the surface of cartilage tissue in the sham operation group was smooth and flat, and the safranin coloration was full in the full thickness of the cartilage;the cartilage tissue in the berberine group showed uneven surface layer, and the staining of safranin O was mildly decreased;the surface layer fibrosis was seen in placebo group, Safranin O faded significantly. The Mankin score in the berberine group was lower than that in placebo group(P<0.01), but higher than that in sham operation group(P<0.01). The structural evaluation of subchondral bone plate showed that the trabecular bone in sham-operated group was densely arranged;after berberine intervention, the trabeculae were closely arranged;the subchondral bone trabeculae in placebo group were relatively sparse, and the distance between trabeculae was wider. Subchondral bone plate IPP software evaluation showed that BV, BV/TV, TC, Tb.Th in berberine group were higher than those in placebo group(P<0.01), BV, BV/TV, TC, Tb.Th in berberine group were higher than those in placebo group(P<0.01), while lower than the sham operation group (P<0.01). PCR test results showed that the expression of OPG mRNA in the berberine group was significantly higher than that in placebo group(P<0.01), and OPG mRNA in the berberine group was lower than that in sham operation group (P<0.01). There was no significant difference in mRNA expression of RANKL among three groups(P>0.05);the ratio of OPG/RANKL in berberine group was higher than that in placebo group(P<0.01), but lower than that in sham operation group(P<0.01).@*CONCLUSION@#Intra-articular injection of berberine can effectively inhibit the resorption of subchondral bone in the early stage of OA and delay the development of the disease. The specific mechanism may be that berberine maintains the balance of OPG/RANKL system by up-regulating the expression of OPG gene in subchondral bone.

Observation of the growth and development of subchondral bone in rat condyles exposed to fluoride at the level of bone microarchitecture / 中华地方病学杂志

Objective:To observe the effect of fluoride on growth and development of bone microstructure of rats condyle subchondral bone (RCSB).Methods:Forty two 3-week-old SD rats (half male and half female) were fed adaptively for 1 week, and 3 females and 3 males were sacrificed and recorded as 0 month. The remaining rats were randomly divided into control group ( n = 18) and fluoride exposed group ( n = 18) according to their body weight (55 - 70 g), half male and half female. The fluoride exposed group was fed with 150 mg/L sodium fluoride (NaF) aqueous solution, and the control group was fed with tap water. The two groups of experimental animals were sacrificed at 3, 5 and 7 month, respectively, 6 rats in each group, half male and half female. The right mandibular condyle was separated, and Micro CT scanning was performed to detect the microstructure parameters of RCSB. Results:In fluoride exposed group (3 month), bone surface/tissue volume (BS/TV), bone surface/bone volume (BS/BV), trabecular thickness (Tb.Th), trabecular number (Tb.N), structure model index (SMI), connectivity, connectivity density (Conn.D) and total porosity of female rats were significantly different from those of male rats ( t = - 5.10, - 5.58, 4.52, - 4.32, - 4.03, - 2.81, - 6.71, - 3.32, P < 0.05). There was no significant difference in each index between female and male rats in fluoride exposed group (5, 7 month, P > 0.05). Conclusion:In chronic fluorine exposure bone environment, the RCSB bone microarchitecture of male and female rats is different with time, showing the tendency of fluoride injury that the bone changes of female rats are slowed and the bone changes of male rats are active.

Molecular mechanism of icariin effects on articular chondrocytes, subchondral bone and synovium in the treatment of osteoarthritis / 中国组织工程研究

BACKGROUND: Icariin is the main effective component of Epimedium, which functions to tonify the kidney, and strengthen tendons and bones. In recent years, a large number of studies have found that icariin plays a significant role in the treatment of osteoarthritis. OBJECTIVE: To review the research progress in the molecular mechanism of icariin in the treatment of osteoarthritis. METHODS: The first author used “Icariin, Osteoarthritis, Cartilage, Subchondral bone, Synovial membrane, synovium, Inflammation" as search words in English and Chinese to search PubMed, CNKI, WanFang, and VIP databases. According to the inclusion criteria and exclusion criteria, 42 articles were included for final analysis. RESULTS AND CONCLUSION: Icariin can promote the cartilage differentiation of bone marrow mesenchymal stem cells and enhance the proliferation of cartilage cells and osteoblasts, to inhibit the degradation of cartilage extracellular matrix, reduce the activity of osteoclasts and alleviate synovial inflammation caused by inflammatory factors. It is an effective treatment for osteoporosis. However, the optimal effective dose and concentration safety of icariin still need a large number of experimental studies. Currently, most of the experiments are still in animal and tissue cell experiments. Numerous clinical studies are needed to continue to explore its specific mechanism in order to provide evidence-based medical evidence for icariin in the treatment of osteoarthritis.

Progress of research on disease-modifying osteoarthritis drugs / 中国药科大学学报

@#Osteoarthritis (OA) is a common chronic joint disease,whose main pathological changes are the degeneration of articular cartilage and secondary bone hyperplasia.The limitation of current treatment methods including pain relief and joint replacement surgery is that they cannot fundamentally improve the damage of articular cartilage.The emergence of disease-modifying osteoarthritis drugs (DMOAD) may break the above limitations.They fundamentally inhibit the structural degeneration of articular cartilage by participating in the regulation of cartilage metabolic balance, regulation of subchondral bone remodeling,and control of local inflammation.Thereby,OA patients will get symptom improvement including pain relief and joint function restoration,delay the artificial joint replacement surgery, and improve the quality of life. There are still no DMOAD drugs widely available on the market worldwide.This paper reviews the background of R&D,the classification of mechanisms of action and research progress of representative drugs under different inechanisms so as to provide reference for future research.

The role of Wnt signaling pathway in osteoarthritis via the dual-targeted regulation of cartilage and subchondral bone / 中国修复重建外科杂志

Objective: To summarize the active changes of Wnt signaling pathway in osteoarthritis (OA) as well as the influence and mechanism of dual-targeted regulation on cartilage and subchondral bone and the role of crosstalk between them on OA process. Methods: The relevant literature concerning the articular cartilage, subchondral bone, and crosstalk between them in OA and non-OA states by Wnt signaling pathway in vivo and vitro experimental studies and clinical studies in recent years was reviewed, and the mechanism was analyzed and summarized. Results: Wnt signaling can regulate the differentiation and function of chondrocytes and osteoblasts through the classic β-catenin-dependent or non-classical β-catenin-independent Wnt signaling pathway and its cross-linking with other signaling pathways, thereby affecting the cartilage and bone metabolism. Moreover, Wnt signaling pathway can activate the downstream protein Wnt1-inducible-signaling pathway protein 1 to regulate the progress of OA and it also can be established gap junctions between different cells in cartilage and subchondral bone to communicate molecules directly to regulate OA occurrence and development. Intra-articular injection of Wnt signaling inhibitor SM04690 can inhibit the progress of OA, and overexpression of Wnt signaling pathway inhibitor Dickkopf in osteoblasts can antagonize the role of vascular endothelial growth factor work on chondrocytes and inhibit the catabolism of its matrix. Conclusion: The regulation of metabolism and function of cartilage and subchondral bone and crosstalk between them is through interactions among Wnt signaling pathway and molecules of other signaling. Therefore, it plays an vital role in the occurrence and development of OA and is expected to become a new target of OA treatment through intervention and regulation of Wnt signaling pathway.

Effect of ibandronate on mitogen-activated protein kinase signaling pathway in rat models of osteoarthritis / 中国组织工程研究

BACKGROUND: Mitogen-activated protein kinase signaling pathway participates in the differentiation of osteoblasts and osteoclasts, closely related to subchondral bone reconstruction and play a key role in the occurrence and development of osteoarthritis. Bisphosphonates as bone resorption inhibitor is used to treat osteoporosis. OBJECTIVE: To observe the effect of sodium ibandronate on the knee osteoarthritis in rats, and changes of mitogen-activated protein kinase signaling pathway. METHODS: The study was approved by the Laboratory Animal Ethical Committee of the First Affiliated Hospital of South China University. Thirty female Sprague-Dawley rats were randomly divided into sham, model, and treatment groups. The rats in the latter two groups underwent ovariectomy bilaterally, and anterior cruciate ligament resection, and rats in the sham group received the fatty tissue surrounding the ovaries removed only. After 1 week of surgery, the rats in the treatment group were given intraperitoneal injection of 10 pg/kg sodium ibandronate, rats in the model group were injected with normal saline, and the sham group received no intervention. Twelve weeks late, the rats were killed to perform histological examination of cartticular cartilage and Mankin scores were detected. Micro-CT of subchondral bone and quantitative analysis of the bone microstructure were conducted. The protein and mRNA expression levels of extracellular signal regulated protein kinase and c-Jun N-terminal kinase in mitogen-activated protein kinase signaling pathway were measured. RESULTS AND CONCLUSION: (1) The cartilage structure in the model group was significantly damaged, the Mankin score was significantly higher than that in the sham group, and the Mankin score in the treatment group was significantly lower than that in the model group (P < 0.01). (2) The bone mineral density, trabecular bone volume ratio, trabecular number in the model group were significantly lower than those in the sham group (P < 0.01), and trabecular separation was higher than that in the sham group (P < 0.01). Compared with the model group, the treatment group had higher bone mineral density, trabecular bone volume ratio, trabecular number, and lower trabecular separation (P < 0.01). (3) The mRNA and protein expression levels of extracellular signal regulated protein kinase and c-Jun N-terminal kinase in the model group were significantly higher than those in the sham group (P < 0.05, P < 0.01), and the levels in the treatment group were significantly lower than those in the model group (P < 0.05). (4) To conclude, sodium ibandronate may inhibit subchondral bone loss and articular cartilage degeneration in rat models of osteoarthritis by inhibiting extracellular signal regulated protein kinase and c-Jun N-terminal kinase in mitogen-activated protein kinase signaling pathway.

Ultrastructural changes of tibial subchondral bone in patients with knee osteoarthritis: CT evaluation / 中国组织工程研究

BACKGROUND: More and more attention has been paid to the role of subchondral bone changes in knee osteoarthritis. However, previous studies mainly focused on animal experiments. Animals and humans have certain differences, so it is very necessary to obtain relevant data directly in human joints. OBJECTIVE: To evaluate the difference of subchondral plate and subchondral bone ultrastructure between normal patients and patients with knee osteoarthritis by CT technique, so as to explore the role of subchondral bone in the occurrence and development of knee osteoarthritis. METHODS: CT scan data of 30 patients with knee osteoarthritis (knee osteoarthritis group) and 30 patients without knee osteoarthritis (non-knee osteoarthritis group) were collected from the Department of Imaging of Zhengzhou Orthopedic Hospital from July 2016 to July 2018. Subchondral plate and subchondral bone ultrastructure of medial and lateral tibial plateau was compared between the two groups using MIMICS software. This study was approved by the Ethics Committee of Zhengzhou Orthopedic Hospital on June 10, 2016 (approval No. 2016 004). RESULTS AND CONCLUSION: (1) Compared with the non-knee osteoarthritis group, bone density was significantly increased and porosity was significantly decreased in the subchondral bone plate in the knee osteoarthritis group in both the lateral and medial parts, while the medial part of subchondral bone plate thickness was significantly thicker than that in the non-knee osteoarthritis group. (2) There were also significant changes in subchondral trabeculae in the knee osteoarthritis group, which showed that the thickness of subchondral trabeculae in the lateral part and the medial part of the subchondral bone in the knee osteoarthritis group was significantly increased compared with the non-knee osteoarthritis group. Meanwhile, in the medial part, the degree of cancellous bone separation in the knee osteoarthritis group was significantly lower than that in the non-knee osteoarthritis group. Structure model index and connectivity density in the knee osteoarthritis group were significantly lower than those of the non-knee osteoarthritis group. (3) Results show that the change of tibial subchondral bone plate and subchondral cancellous bone in knee osteoarthritis patients mainly lies in the destruction of ultrastructure homeostasis. This change may be one of the causes of knee osteoarthritis.

Local injection of halofuginone into the subchondral bone relieves canine osteoarthritis by inhibiting transforming growth factor beta 1 signaling pathway / 中国组织工程研究

BACKGROUND: Studies have shown that the increase of bone resorption in osteoclasts over-activates transforming growth factor beta 1 (TGF-ß1), and uncouples bone resorption and bone formation, ultimately leading to a hardened phenotype of the subchondral bone In an animal model of osteoarthritis. Progression of osteoarthritis can be attenuated by inhibiting TGF-ß1 signaling pathway. OBJECTIVE: To detect whether osteoarthritis progression can be delayed by the local Injection of halofuglnone In Beagle models of osteoarthritis. METHODS: Eighteen male Beagle dogs were randomized into a sham (control) group, a model (osteoarthritis) group, or a treatment (halofuglnone) group. Animal models of osteoarthritis were made by anterior cruciate ligament transection in the latter two groups. Animals In the treatment group were given local injection of halofuglnone (37.8 ng) Into the subchondral bone. Serum levels of type II collagen C-terminal peptide (CTX-II) and type X collagen a1 chain (COLI 0A1) were measured at 4, 8,12, and 16 weeks after modeling. The Beagle dogs were sacrificed at the 16th week after surgery, and the alterations of microarchitecture of the subchondral bone were detected by micro-CT. Articular cartilage degeneration was graded using safranin О and fast green staining combined with the Osteoarthritis Research Society International (OARSI)-modified Manklng criteria. Immunostaining analyses were conducted to detect the expression levels of TGF-ß1 and matrix metalloprotelnase 13. The study protocol was approved by the Animal Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University, with the approval No. IACUC20160304-07. RESULTS AND CONCLUSION: The COL10A1 level In the model group was higher than that in the control group and the treatment group at 8 and 12 weeks after modeling (P 0.05). Overall, local Injection of halofuginon attenuates anterior cruciate ligament transection-lnduced osteoarthritis by inhibiting abnormally elevated TGF-ß1 In the subchondral bone and blocking abnormal bone remodeling. Therefore, local Injection of halofuginon may be a new therapeutic alternative for osteoarthritis.

Artesunate relieves subchondral bone osteoclast-mediated osteoarthritis pain / 中国组织工程研究

BACKGROUND: Studies have shown that osteoclasts induce aberrant in growth of sensory nerves into the subchondral bone by secreting netrin-1, resulting in a reduced pain threshold in an osteoarthritis animal model. Therefore, we assume that inhibition of osteoclasts can alleviate sensory nerve-mediated pain symptoms. OBJECTIVE: To investigate whether artesunate inhibits subchondral bone osteoclasts and reduces sensory nerve-mediated pain, providing experimental data for the treatment of osteoarthritis pain using artesunate. METHODS: C57BL/6J male mice were randomly assigned to a sham operation group, a placebo group and an artesunate group, with 10 mice per group. The mice in the sham operation group were only subjected to right knee capsulotomy with no damage to the other structures. Moreover, there was no intervention after operation. In the other two groups, the mice received an anterior cruciate ligament transection of the right knee to establish the osteoarthritis model, followed by treatment with artesunate (artesunate group, 100 mg/kg per day) or equivalent volume of 5% NaHCO3 (placebo group) via intraperitoneal injection. Fourteen days after surgery, the footprint trial was performed, and the levels of tartrate-resistant acid phosphatase 5b (TRAcP5b), cathepsin K and carboxy-terminal telopeptide of type I collagen (CTX-I) in the peripheral blood were detected using ELISA. The knee joint specimens of each group were subjected to Safranin O-Fast Green staining, histological scoring, tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemical staining with netrin-1 and calcitonin gene-related peptide (CGRP). RESULTS AND CONCLUSION: The percentage of ipsilateral contact area of the right hindpaw in the footprint trial was significantly higher in the sham operation group and artesunate group than the placebo group (P 0.05). No significant differences were observed in the serum levels of TRAcP5b, cathepsin K and CTX-I between the groups (P > 0.05). Based on the Safranin O-Fast Green staining, the cartilage histology score was significantly lower in the sham operation group and the artesunate group than the placebo group (P 0.05). TRAP staining indicated that compared with the placebo group, the Trap+ osteoclasts were significantly lower in the sham operation group and the artesunate group (P 0.05). Compared with the placebo group, the netrin-1+ and CGRP+ sensory nerves in the subchondral bone were significantly decreased in the sham operation group and the artesunate group (P 0.05). Our findings from this study indicate that artesunate improves sensory nerve-mediated pain by inhibiting netrin-1 secreted by subchondral bone osteoclasts, and has therapeutic potential to alleviate osteoarthritis pain.

Expression and role of retinoblastoma RB1-inducible coiled-coil 1 in the subchondral bone of osteoarthritis / 中国组织工程研究

BACKGROUND: Osteoarthritis is mainly characterized by degeneration of the articular cartilage and reconstruction of the subchondral bone. The specific pathogenesis of osteoarthritis is still unclear. Most studies have used cartilage and subchondral bone as the main entry point to explore the molecular mechanism and signal pathway changes in the disease progression, providing new biological targets and research direction for the diagnosis and treatment of osteoarthritis. OBJECTIVE: To investigate the expression of RB1-inducible coiled-coil 1 (RB1CC1) in the subchondral bone during the development of osteoarthritis. METHODS: Eight-week-old C57 mice were randomly divided into experimental group and sham operation group. Experimental group was then randomly divided into two subgroups of 4 weeks and 8 weeks. In the experimental group, the tibia ligament of the right knee was cut off to dissociate the medial meniscus to induce osteoarthritis. In the sham operation group, only the joint capsule was cut without medial ligament resection and meniscus dissociation. The study was implemented with an experimental animal ethic approval from the Third Affiliated Hospital of Southern Medical University, China (approval No. 44007200038731) on December 13, 2017. RESULTS AND CONCLUSION: Compared with the sham operation group, the Osteoarthritis Research Society International scores were increased significantly in the experimental group. Compared with the sham operation group, the expression of collagen II was decreased, and RB1CC1 in the subchondral bone was gradually increased in the experimental group, which was consistent with the expression trend of BSP2. To conclude, with the development of osteoarthritis, the expression of RB1CC1 in the subchondral bone is gradually increased, which may be related to the increase of hyperplasia in the subchondral bone and remodeling.

Relationship of Subchondral Plate-Rod Structure and Cartilage Degeneration with Lower Limb Alignment / 医用生物力学

Objective To study the relationship of the tibial plateau subchondral trabecular bone (STB) microstructure and the cartilage degeneration with the lower limb alignment based on individual trabecula segmentation (ITS) and histology analysis in knee osteoarthritis (OA). Methods Hip-knee-ankle (HKA) angles were measured on the full-length lower extremity films of patients before total knee arthroplasty (TKA). The tibial plateau excised from the TKA were collected for micro-CT scanning and ITS analysis. The cartilage degeneration was evaluated by histology. The relationship between the HKA angle and the changes in microstructural parameters of STB and cartilage degeneration were analyzed. ResultsThe plate, rod and axial bone trabecular volume fraction (BV/TV, pBV/TV, pBV/TV), ratio of trabecular plate versus rod (P/R), plate trabecular number density (pTb.N), plate trabecular thickness (pTb.Th), trabecular plate surface area (pTb.S), trabecular rod length (rTb.L), and plate-plate and plate-rod junction density (P-P Junc.D, P-R Junc.D) of the subchondral bone of the tibial plateau were significantly related to the cartilage degeneration OARSI score and the HKA angle. The greater the deviation of the lower limb alignment, the greater the number of subchondral trabeculae, the thicker the trabeculae, the greater the bone mass, the stronger the connectivity, especially the plate trabeculae on the affected side of tibial plateau, and the higher the OARSI score of cartilage degeneration. Conclusions Abnormal lower limb alignment may cause abnormal microstructure of the plate and rod STB of the tibial plateau by changing the stress distribution of the knee, especially the significant increase and thickening of the plate trabecular and axial trabecular bone, which may be an important risk factor that further aggravates the degeneration of articular cartilage and the progress of OA. Therefore, lower limb alignment correction with surgical intervention and improving STB with bone metabolism agents may efficiently contribute to preventing cartilage damage and mitigate OA progression.

Research Progress on Changes and Interaction Mechanisms of Aging Articular Cartilage and Subchondral Bone / 医用生物力学

Aging is a major risk factor for diseases such as osteoarthritis (OA) and osteoporosis. However, they are not necessarily the results of aging, and the relationship between changes in bone and cartilage associated with aging and disease progression is still unclear. Studies have shown that the development and progression of OA is not a simple cartilage wear process, while its occurrence involves complex biological, chemical and mechanical changes in the tissues of the entire joint, especially the interaction of mechanics and biochemistry between cartilage and subchondral bone. Aging contributes to the occurrence and development of OA, but it is not the cause of OA. Changes associated with aging provide a foundation for OA to start, making joints more susceptible to other factors such as abnormal biomechanics and biochemistry, thereby promoting the development of OA. Therefore, understanding the basic mechanisms by which aging affects joint tissue may provide new targets for slowing or preventing the development of OA. In this paper, the related research progresses are reviewed from three aspects, i.e. age-related changes in cartilage and subchondral bone, mechanical conduction and angiogenesis.

Does cartilageER-alpha overexpression correlate with osteoarthritic chondrosenescence? Indications from Labisia pumila OA mitigation

Crop productivity and yield are adversely affected by abiotic and biotic stresses. Therefore, finding out the genesresponsible for stress tolerance is a significant stride towards crop improvement. A gene co-expression network is apowerful tool to detect the most connected genes during heavy metal (HM) stress in plants. The most connected genes maybe responsible for HM tolerance by altering the different metabolic pathways during the biotic and abiotic stress. In thesame line we have performed the GSE86807 microarray analysis of chickpea during exposure to chromium, cadmium andarsenic and analyzed the data. Common differentially expressed genes (DEGs) during exposure to chromium, cadmium andarsenic were identified and a co-expression network study was carried out. Hub and bottleneck genes were explored on thebasis of degree and betweenness centrality, respectively. A gene set enrichment analysis study revealed that genes likehaloacid dehydrogenase, cinnamoyl CoA reductase, F-box protein, GDSL esterase lipase, cellulose synthase, b-glucosidase13 and isoflavone hydroxylase are significantly enriched and regulate the different pathways like riboflavin metabolism,phenyl propanoid biosynthesis, amino acid biosynthesis, isoflavonoid biosynthesis and indole alkaloid biosynthesis.

Effects of Ligustrazine on miR- 20b/VEGF and BMP 2/Smad1 Pathways in Subchondral Bone of Knee Osteoarthritis Model Rats / 中国药房

OBJECTIVE： To study the effects of ligustrazine on miR-20b/VEGF and BMP2/Smad1 pathways in subchondral bone of knee osteoarthritis （KOA） model rats， and to investigate the mechanism of ligustrazine for KOA prevention and treatment. METHODS： Totally 18 healthy male SD rats were randomly divided into normal control group， model group and ligustrazine group， with 6 rats in each group. The rats in the latter two groups were used to establish KOA model by intra-articular injection of 4％ papain solution. From the 2nd day after the last injection， ligustrazine group was given intragastrical administration of Ligustrazine suspension （100 mg/kg） 2 mL； normal control group and model group were given intragastrical administration of isometrical normal saline， once a day， for consecutive 6 weeks. After the last after medication， the situation of bilateral knee articular cartilage of rats were observed after exposure. The knee joints of rats were sectioned and stained with HE. The pathological change of articular cartilage were observed by microscope and scored by modified Mankin’s score. mRNA expression of VEGF， BMP2 and Smad1， and the expression of miR-20b were detected by RT-PCR； the protein expression of VEGF， BMP2 and Smad1 were detected by Western blot assay. RESULTS： Model group and ligustrazine group suffered from cartilage injury of knee joint at varying degrees. Compared with normal control group， Mankin’s scores of knee joint and cartilage tissue were increased significantly in model group （P＜0.01）； mRNA and protein expression of BMP and Smad1， the expression of miR-20b in subchondral bone of model group were decreased significantly， while mRNA and protein expression of VEGF were increased significantly （P＜0.01）. Compared with model group， Mankin’s score of cartilage tissue were decreased significantly in ligustrazine group （P＜0.01）； mRNA and protein expression of BMP and Smad1， the expression of miR-20b in subchondral bone were increased significantly， while mRNA and protein expression of VEGF were decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS： Ligustrazine can repair damaged articular cartilage in KOA model rats， the mechanism of which may be associated with inhibiting the protein expression of VEGF and activating BMP-2/Smad1 signaling pathway via up-regulating the expression of miR-20b， and promoting the degradation of VEGF mRNA in subchondral bone.

A better knowledge of the relationship between osteoarthritis and osteoporosis may help the stratification treatment / 中国实用内科杂志

TO understand the relationship between osteoarthritis(OA) and osteoporosis as well as the subtypes of OA may pave the way for patient stratification and the development of precision medicines for OA. Osteoporosis(OP) may cause OA development,while OA patients have higher risk for fracture. Abnormal subchondral bone remodeling and subsequent microstructural damage is key pathogenesis of osteoporotic OA. Bone-acting agents, such as bisphosphonate, may be a new choice for osteoporotic OA.

Local administration of halofuginone via osmotic infusion pumps inhibits transforming growth factor-β signaling in subchondral bone / 中华创伤骨科杂志

Objective To explore the impact of inhibition of transforming growth factor-β(TGF-β) signaling by local administration of halofuginone (HF) via osmotic infusion pumps on osteoarthritis (OA) pathogenesis and its underlying mechanism.Methods Knee OA models were induced by the anterior cruciate ligament transection (ACLT) in 30 3-month-old male SD rats.They were randomized by random number table into 3 equal groups (n =10):Sham,Vehicle + ACLT and HF + ACLT ones.Specific administration of drugs was achieved via osmotic infusion pumps directly implanted in subchondral bone.Safranin 0 and fast green,H&E,immunofluorescence staining,CT-based microangiography and bone micro-CT (μCT) were used to measure alterations in articular cartilage and subchondral bone [BV(bone volume)/TV (tissue volume),Tb.Pf (trabecular pattern factor),Tb.N (trabecular number),SBP.Th(subchondral bone plate.Th),pSmad2/3,Nestin,and OARSI (Osteoarthritis Research Society International) scoring].Results Knee OA models and drug administration devices in subchondral bone were successfully established in rats.Sham and HF + ACLT groups had greater subchondral BV/TV(0.381 ± 0.060 mm3 and 0.322 ±0.060 mm3),SBP.Th (0.570 ±0.042 mm and 0.521 ±0.122 mm) and Tb.N (4.871 ±0.214 mm-1 and 4.364 ±0.466 mm-1) than Vehicle +ACLT group did (0.229±0.063) mm3,0.324±0.165 mm and 2.978±0.804 mm-1,respectively);Sham and HF +ACLT groups had less subchondral Tb.Pf (-0.880 ±0.210 mm-1 and -0.377±0.259 mm-1),lower expression of pSmad2/3 (90.2±40.0 and 90.8±34.5) and Nestin (16.9 ± 5.8 and 18.5 ± 4.7) and OARSI scores (1.2 ± 0.7 and 2.5 ± 1.9) than Vehicle + A CLT group did (0.057 ± 0.535 mm-1,142.7 ± 37.0,25.9 ± 7.4 and 5.4 ± 2.8,respectively).All the above differences were statistically significant (P ＜ 0.05).There were no significant differences between Sham and HF + A-CLT groups in subchondral BV/TV,Tb.Pf,Tb.Pf,SBP.Th,Tb.N,expression of pSmad2/3 or Nestin,or OARSI scores (P ＞ 0.05).Conclusion Subchondral administration of HF can inhibit TGF-β induced erroneous recruitment of mesenchymal stem cells in subchondral bone,thus attenuating OA progression.

Role of the Subchondral Bone in Osteoarthritis / 中国医科大学学报

Temporomandibular joint osteoarthritis (OA) is the most severe type of temporomandibular joint disorder of the oral and maxillofacial region. This disorder has a high incidence, and its main characteristic is articular cartilage injury, accompanied by changes in the synovium and subchondral bone. The role of the changes in the subchondral bone in the development and progression of OA has attracted attention in recent years, and the importance of the subchondral bone has been recognized. At present, the subchondral bone has been considered a promising target for the treatment of OA. This manuscript summarizes the research progress in the pathological changes of the cartilage bone in OA, and its mechanism, which would be helpful for the treatment of this disease.

The effects of estrogen on the degenerative changes of rat condylar cartilage and subchondral bone / 实用口腔医学杂志

Objective: To study the effects of estrogen on the degenerative changes of condylar cartilage and subchondral bone in rats. Methods: 18 female SD rats aged 6 weeks were divided into control(C),unilateral anterior cross-bite(UAC) and UAC treated with estrogen(UAC + E) groups(n = 6). UAC metal prosthesis was cemented to the left incisors of maxilla and mandible of the rats in group UAC and UAC + E. Rats in UAC + E group were given pexitoneal injection of 80 μg 17β-estradiol per day. The rats in group C were untreated. Animal were sacrificed at the 4th weeks. The micro-structure of subchondral bone was observed by Micro-CT scanning. HE staining,Safranin O staining,immunohistochemical staining,TUNEL staining and TRAP staining for the observation of pathological changes of histomorphology,extracellular matrix,chondrocyte apoptosis in condylar cartilage,and osteoclasts number in subchondral bone. Results: UAC and UAC + E group showed evident osteoarthritis(OA)-like lesions. Compare with UAC group,there was a significant decrease in the expression of proteoglycan(P ＜ 0. 05),type Ⅱ collagen(P ＜ 0. 01),and a significant increase in the number of apoptotic chondrocytes(P ＜ 0. 01) in UAC + E group. As for subchondral bone,the BV/TV,Tb. Th parameters in C and UAC + E groups were significant higher than in UAC group(P ＜ 0. 01),while the BS /BV,Tb. N,Tb. Sp parameters and the osteoclasts number in C and UAC + E groups were significant fewer than in UAC groups(P ＜ 0. 01). There was no significant difference in bone ultra-parameters and osteoclasts number between C and UAC + E groups(P＞ 0. 05). Conclusion: In the model of rat TMJOA induced by unilateral anterior crossbite prosthesis,supra-physiological level of estrogen can reverse bone loss in subchondral bone,but accelerate the degradation of condylar cartilage.

Electroacupuncture Intervention Improves Cartilage Degeneration and Subchondral Bone Osteoporosis of Knee-joint Possibly by Adjusting OPG/RANK/RANKL Signaling in Ovariectomized Rats / 针刺研究

OBJECTIVE: To observe the effect of electroacupuncture (EA) on histopathological changes of cartilage and subchondral bone and osteoprotegerin (OPG)，receptor activator of nuclear factor-κB (RANK), and RANK ligand (RANKL) (OPG/RANK/RANKL) signaling and the expression of matrix metalloproteinase-13 (MMP-13) in ovariectomized(OVX)rats, so as to explore its mechanism underlying improvement of osteoporosis. METHODS: Three-month female SD rats were randomly divided into sham operation, model and EA groups (n＝8 in each group). The ovoariectomy model was established by resection of bilateral ovaries. Rats of the sham group were treated by simple removal of a piece of adipose tissue around the bilateral ovaries. EA (3 Hz/15 Hz, 1 mA) was applied to bilateral "Sanyinjiao" (SP 6), "Yanglingquan" (GB 34), "Yinlingquan" (SP 9) and "Zusanli" (ST 36) for 30 min, once daily (except the weekends) for 12 weeks. The histopathological changes of the subchondral bone of the right knee-joint were observed after Saffron O dyeing and evaluated by Mankin's score, and its anatomical structure including the bone volume fraction (bone volume/tissue volume, BV/TV), trabecular bone number (Tb. N) and trabecular thickness (Tb.Th), trabecular separation (Tb.Sp) was observed by using Micro CT imaging. The urine C-terminal cross-linking telopeptide of type Ⅰ collagen (CTX-Ⅰ), CTX-Ⅱ (two bone resorption markers) and serum estrogen (E 2) contents were assayed by ELISA, and the expression levels of OPG, RANKL and MMP-13 mRNAs in the cartilage tissue of the left knee-joint were detected by quantitative RT-PCR. RESULTS: Following modeling, the BV/TV, Tb. N and Tb.Th levels were significantly decreased (P<0.01) and Tb.Sp and Mankin's score obviously increased in the model group compared with the sham group (P<0.01), suggesting a formation of osteoporosis and degeneration of the cartilage tissue. The serum E 2 content and OPG mRNA level in the cartilagetissue were significantly down-regulated (P<0.01), and urine CTX-Ⅰ and CTX-Ⅱ contents and RANKL mRNA and MMP-13 mRNA expression levels cartilagetissue were considerably up-regulated in the model group relevant to the sham group (P<0.01). After EA intervention, modeling-induced decrease of BV/TV, Tb.N, Tb.Th, E 2 and OPG mRNA levels and OVX-induced increase of Tb.Sp, Mankin's score, CTX-Ⅰ， CTX-Ⅱ， RANKL mRNA and MMP-13 mRNA levels were all completely reversed in the EA group relevant to the model group (P<0.01，P<0.05)．. CONCLUSION: EA intervention can inhibit subchondral bone osteoporosis and articular cartilage degeneration of knee-joint in OVX rats, which is closely associated with its effects in inhibiting the down-regulation of serum E 2 and OPG mRNA expression and up-regulation of CTX-Ⅰ， CTX-Ⅱ， RANKL mRNA and MMP-13 mRNA levels, including adjusting OPG/RANK/RANKL signaling.