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Journal: Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society

167

OBJECTIVE: The 1-34 amino acid segment of the parathyroid hormone (PTH [1-34]) mediates anabolic effects in chondrocytes and osteocytes. The aim of this study was to investigate whether systemic application of PTH [1-34] improves the repair of non-osteoarthritic, focal osteochondral defects in vivo. DESIGN: Standardized cylindrical osteochondral defects were bilaterally created in the femoral trochlea of rabbits (n = 8). Daily subcutaneous injections of 10 μg PTH [1-34]/kg were given to the treatment group (n = 4) for 6 weeks, controls (n = 4) received saline. Articular cartilage repair was evaluated by macroscopic, biochemical, histological and immunohistochemical analyses. Reconstitution of the subchondral bone was assessed by micro-computed tomography. Effects of PTH [1-34] on synovial membrane, apoptosis, and expression of the PTH receptor (PTH1R) were determined. RESULTS: Systemic PTH [1-34] increased PTH1R expression on both, chondrocytes and osteocytes within the repair tissue. PTH [1-34] ameliorated the macro- and microscopic aspect of the cartilaginous repair tissue. It also enhanced the thickness of the subchondral bone plate and the microarchitecture of the subarticular spongiosa within the defects. No significant correlations were established between these coexistent processes. Apoptotic levels, synovial membrane, biochemical composition of the repair tissue, and type-I/II collagen immunoreactivity remained unaffected. CONCLUSIONS: PTH [1-34] emerges as a promising agent in the treatment of focal osteochondral defects as its systemic administration simultaneously stimulates articular cartilage and subchondral bone repair. Importantly, both time-dependent mechanisms of repair did not correlate significantly at this early time point and need to be followed over prolonged observation periods.

Concepts: Bone, Calcitonin, Collagen, Extracellular matrix, Parathyroid hormone, Cartilage, Autologous chondrocyte implantation, Articular cartilage repair

166

Osteoarthritis is a leading cause of pain and disability and leads to a reduced quality of life. The aim was to determine the current evidence on risk factors for onset of knee pain/osteoarthritis in those aged 50 and over.

Concepts: Death, Evidence-based medicine, Systematic review, Management, Meta-analysis

37

To develop concise, up-to-date, patient-focused, evidence-based, expert consensus guidelines for the management of knee osteoarthritis, intended to inform patients, physicians, and allied health care professionals worldwide.

Concepts: Health care, Health care provider, Medicine, Healthcare, Patient, Osteoarthritis, Illness, Allied health professions

34

31

Osteoarthritis (OA) is the most common form of arthritis and a leading cause of disability worldwide, largely due to pain, the primary symptom of the disease. The pain experience in knee OA in particular is well-recognized as typically transitioning from intermittent weight-bearing pain to a more persistent, chronic pain. Methods to validly assess pain in OA studies have been developed to address the complex nature of the pain experience. The etiology of pain in OA is recognized to be multifactorial, with both intra-articular and extra-articular risk factors. Nonetheless, greater insights are needed into pain mechanisms in OA to enable rational mechanism-based management of pain. Consequences of pain related to OA contribute to a substantial socioeconomic burden.

Concepts: Medicine, Epidemiology, Disease, Rheumatoid arthritis, Osteoarthritis, Knee, Joint, Kanye West

28

OBJECTIVE: The present study was performed to elucidate the possible role of SIRT1 signaling in joint inflammation in human articular chondrocytes. DESIGN: Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting were performed to detect gene products and proteins involved in tumor necrosis factor α (TNF-α)-induced inflammation and cartilage degradation in human primary chondrocytes. Matrix metalloproteinase (MMP)-2 and MMP-9 activity was evaluated by gelatin zymography. Overexpression and knockdown of SIRT1 were also performed to investigate whether SIRT1 is associated with the anti-inflammatory activity of resveratrol in chondrocytes. RESULTS: Resveratrol dose-dependently inhibited TNF-α-induced COX-2, MMP-1, MMP-3, MMP-13 and PGE(2) production in human chondrocytes. Moreover, MMP-2 and MMP-9 activity was increased by treatment with TNF-α; however, SIRT1 activation decreased the pro-inflammatory effects induced by TNF-α. In addition, treatment of SIRT1 activator and overexpression of SIRT1 inhibited the expression and activation of the main pro-inflammatory regulator NF-κB, which was increased by TNF-α. When SIRT1 was overexpressed in chondrocytes, the anti-inflammatory action of SIRT1 was similar to that exerted by resveratrol. CONCLUSIONS: SIRT1 activation deacetylates and inactivates NF-κB, and thereby, exerts an anti-inflammatory effect on chondrocytes, suggesting that SIRT1 activators could be explored as potential treatments for arthritis.

Concepts: DNA, Gene expression, Polymerase chain reaction, Molecular biology, Histone deacetylase, Real-time polymerase chain reaction, Tumor necrosis factor-alpha, Laboratory techniques

28

MicroRNAs (miRNAs) play an important role in the regulation of chondrogenesis of mesenchymal stem cells, but their expression still remains unknown in human adipose-derived stem cells (hADSCs). In this study the miRNA expression profile during chondrogenic differentiation of hADSC and the potential mechanism whereby miRNAs may affect the process of chondrogenesis are considered.

Concepts: DNA, Gene, Gene expression, Stem cell, Mesenchymal stem cell, Bone marrow, MicroRNA, Cellular differentiation

28

The aim of this study was to examine serum non-coding RNAs as potential biomarkers for cartilage damage associated with anterior cruciate ligament (ACL) injury.

Concepts: Osteoarthritis, Knee, Anterior cruciate ligament, Ligament, Anterior cruciate ligament injury, Anterior cruciate ligament reconstruction, Cruciate ligament, Ligaments

28

Recent scientific advances in the treatment of hip and knee osteoarthritis (OA) relating to education, exercise, weight control and passive non-pharmacological and non-surgical treatments such as manual therapy, orthoses/orthotics and other aids are described.

Concepts: Obesity, Sartorius muscle

27

To identify and validate previously established phenotypes of knee osteoarthritis (OA) based on similarities in clinical patient characteristics.

Concepts: Patient