Dehydroepiandrosterone and age-related musculoskeletal diseases: Connections and therapeutic implications.

Musculoskeletal disorders related to ageing are one of the most common causes of mortality and morbidity among elderly individuals worldwide. The typical constitutive components of the musculoskeletal system, including bone, muscle, and joints, gradually undergo a process of tissue loss and degeneration as a result of life-long mechanical and biological stress, ultimately leading to the onset of a series of age-related musculoskeletal diseases, including osteoporosis (OP), sarcopenia, and osteoarthritis (OA). Dehydroepiandrosterone (DHEA), a precursor of androgen secreted mainly by the adrenal gland, has attracted much attention as a marker for senescence due to its unique age-related changes.

Tricetin Protects Rat Chondrocytes against IL-1-Induced Inflammation and Apoptosis.

Tricetin is a well-studied flavonoid with a wide range of pharmacological activities in cancer and inflammation. However, the ability of tricetin to ameliorate the inflammation that occurs in osteoarthritis (OA) has not been determined. This study explored the effects of tricetin on interleukin- (IL-) 1-induced rat chondrocytes.

Paeoniflorin inhibits IL-1β-induced MMP secretion via the NF-κB pathway in chondrocytes.

Paeoniflorin serves important cellular roles, exerting anti-cancer, anti-inflammatory and anti-pulmonary fibrosis effects and possesses immune-modulatory properties. However, the exact role of paeoniflorin in the pathogenesis of osteoarthritis (OA) remains unclear. The aim of the present study was to investigate the effects of paeoniflorin on articular surfaces .

Dehydroepiandrosterone and Experimental Osteoarthritis.

Despite an increased understanding of the pathogenesis of osteoarthritis (OA) and the availability of a number of drugs designed to ameliorate its symptoms, a successful disease-modifying therapy remains elusive. Recent lines of evidence suggest that dehydroepiandrosterone (DHEA), a 19-carbon steroid hormone classified as an adrenal androgen, exerts a chondroprotective effect in OA patients, and it has been proven to be an effective DMOAD candidate that slows OA progression. However, the exact mechanisms underlying its anti-OA effect is largely unknown.

Paeoniflorin inhibits IL-1β-induced chondrocyte apoptosis by regulating the Bax/Bcl-2/caspase-3 signaling pathway.

Apoptosis serves a pivotal role in the pathogenesis of osteoarthritis (OA). Increasing evidence has demonstrated that paeoniflorin exerts key properties (including anticancer, anti-inflammation and neuroprotective) for clinical applications. However, the precise role of paeoniflorin in articular cartilage apoptosis remains unknown.

Rosmarinic acid down-regulates NO and PGE expression via MAPK pathway in rat chondrocytes.

Rosmarinic acid (RosA) is a water-soluble polyphenol, which can be isolated from many herbs such as orthosiphon diffuses and rosmarinus officinalis. Previous studies have shown that RosA possesses various biological properties. In this study, we investigate the anti-osteoarthritic effects of RosA in rat articular chondrocytes.

Vaspin prevents leptin‑induced inflammation and catabolism by inhibiting the activation of nuclear factor‑κB in rat chondrocytes.

The present study aimed to investigate the function and possible underlying mechanism of various concentrations of visceral adipose tissue‑derived serine protease inhibitor (vaspin) on leptin‑induced inflammatory and metabolic responses in rat chondrocytes. Rat articular chondrocytes were isolated and treated with different concentrations of vaspin, which was followed by stimulation with leptin. The expression of genes, secretion of nitric oxide and tumor necrosis factor‑α, and activation of the nuclear factor (NF)‑κB pathway were analyzed by reverse transcription‑quantitative polymerase chain reaction, ELISA and western blotting.

The disease-modifying effect of dehydroepiandrosterone in different stages of experimentally induced osteoarthritis: a histomorphometric study.

Background: Osteoarthritis (OA) is likely to become an increasing burden in the coming decades. Various agents have been developed to slow the progression of OA, and are collectively known as 'disease-modifying drugs', however, there is still little reliable evidence that such agents will be successful. Dehydroepiandrosterone (DHEA), a sex hormone precursor, has been recently proven as protective agent against OA, but the exact mechanism is still unkown.

Baicalein Inhibits MMPs Expression via a MAPK-Dependent Mechanism in Chondrocytes.

Background: Baicalein is a flavonoid isolated from Scutellaria baicalensis Georgi. Here, we investigated the anti-osteoarthritic effect of baicalein in vitro and in vivo.

Methods: Interleukin-1 beta (IL-1β)-induced chondrocytes were treated with different concentrations of baicalein, real-time PCR and ELISA were performed to detect the matrix metalloproteinases (MMPs) expression.

Acacetin inhibits expression of matrix metalloproteinases via a MAPK-dependent mechanism in fibroblast-like synoviocytes.

It is well known that rheumatoid arthritis (RA) is an autoimmune joint disease in which fibroblast-like synoviocytes (FLSs) play a pivotal role. In this study, we investigated the anti-arthritic properties of acacetin in FLSs. The expression of matrix metalloproteinase (MMP)-1, MMP-3 and MMP-13 were investigated by quantitative RT-PCR and western blot at gene and protein levels.

Expression of vaspin in the joint and the levels in the serum and synovial fluid of patients with osteoarthritis.

The aim of this study was to determine the expression of vaspin in the joint and investigate the distribution between paired serum and synovial fluid (SF) in osteoarthritis (OA) patients, and serum in healthy controls. The gene expression of vaspin was measured by quantitative real-time polymerase chain reaction (qPCR) in the OA joint tissues. The vaspin protein expression in the cartilage, synovium and osteophyte from OA patients who required total knee replacement (TKR) were detected by immunohistochemistry (IHC).

Hinokitiol reduces matrix metalloproteinase expression by inhibiting Wnt/β-Catenin signaling in vitro and in vivo.

Objective: In this study, we investigated the effects of hinokitiol on matrix metalloproteinase (MMP)-1, -3, -13, collagen type II (Col2a1) and β-catenin expressions in rat chondrocytes induced by interleukin-1β and in an experimental rat model induced by intra-articular injection of mono-iodoacetate (MIA) into the knee.

Methods: Chondrocytes were cultured from the articular cartilage of 2-week-old rats. Passaged chondrocytes were pretreated with hinokitiol for 2h followed by co-incubation with IL-1β for 24h.

Visceral adipose tissue-derived serine protease inhibitor inhibits interleukin-1β-induced catabolic and inflammatory responses in murine chondrocytes.

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is a newly identified member of the adipocytokine family, whose precise role in chondrocyte metabolism remains to be elucidated. The aim of the present study was to investigate the effect of vaspin on chondrocytes. The cell viability and the cytotoxicity of vaspin in chondrocytes were examined.

Astaxanthin reduces matrix metalloproteinase expression in human chondrocytes.

Astaxanthin is a red carotenoid pigment which exerts multiple biological activities. However, little is known about the effects of astaxanthin on matrix metalloproteinases (MMPs) in OA. The present study investigated the effects of astaxanthin on MMPs in human chondrocytes.

Stigmasterol blocks cartilage degradation in rabbit model of osteoarthritis.

Stigmasterol has been shown exhibit anti-osteoarthritic properties in vitro studies. However, the in vivo effects of stigmasterol on cartilage are still unclear. This study investigated the anti-osteoarthritic properties of stigmasterol on cartilage degradation in a rabbit model of osteoarthritis (OA).

Morin exerts antiosteoarthritic properties: an in vitro and in vivo study.

Morin is a flavonoid isolated from members of the Moraceae family. Morin has been reported to possess antioxidative and anticarcinogenic activities. However, the antiosteoarthritic properties of morin have not been investigated.

Morin inhibits interleukin-1β-induced nitric oxide and prostaglandin E2 production in human chondrocytes.

It is well known that the inflammatory cytokines play important roles in osteoarthritis (OA). In the present study, we investigated the anti-inflammatory properties of morin in chondrocytes. The nitric oxide (NO) production was determined by Griess method, the prostaglandin E2 (PGE(2)) production was detected by Enzyme-linked immunosorbent assay (ELISA).

Thymoquinone inhibits matrix metalloproteinase expression in rabbit chondrocytes and cartilage in experimental osteoarthritis.

Thymoquinone (TQ) is the main constituent of Nigella sativa oil, which has been traditionally used against arthritis in the Middle East. In this study, we investigated the effect of TQ against matrix metalloproteinase (MMP) expression in both rabbit chondrocytes and animal mode of osteoarthritis (OA) induced by anterior cruciate ligament transection and tested whether or not nuclear factor kappa B (NF-κB) was involved in this process. TQ down-regulated MMP-1, MMP-3 and MMP-13 expression and up-regulated tissue inhibitors of metalloproteinase-1 expression as assessed by quantitative realtime polymerase chain reaction.

Protective effects of berberine in an experimental rat osteoarthritis model.

Berberine shows anticancer, antibacterial, antiinflammatory and antioxidant effects and may be useful in many clinical applications. The effects of berberine on articular cartilage metabolism remain unknown, so this study was performed to evaluate these effects in vitro and in vivo. For the in vitro work, rat articular chondrocytes were cultured in a monolayer and matrix metalloproteinase-1 (MMP-1), -3, -13 and tissue inhibitor of metalloproteinase (TIMP-1) expression was evaluated by real-time quantitative PCR.

Effect of dehydroepiandrosterone on aggrecanase expression in articular cartilage in a rabbit model of osteoarthritis.

To investigate the in vivo effect of dehydroepiandrosterone (DHEA) on the expression of aggrecanases and their endogenous inhibitor in a rabbit model of OA. Ten New Zealand white rabbits underwent bilateral anterior cruciate ligament transection (ACLT). One knee of each rabbit was randomly assigned to receive 100 μM DHEA dissolved in dimethylsulphoxide (DMSO) and the other was treated with DMSO only.

Anti-arthritic effects of chlorogenic acid in interleukin-1β-induced rabbit chondrocytes and a rabbit osteoarthritis model.

Cartilage degradation is one of the pathological changes of osteoarthritis (OA), and accumulating evidence suggests an excess of matrix metalloproteinases (MMPs) plays a role in this cartilage breakdown. Here, we investigated the effects of chlorogenic acid (CGA) on the mRNA and protein expression of MMPs in interleukin (IL)-1β-induced rabbit chondrocytes and evaluated the in vivo effects of CGA in experimental OA induced by anterior cruciate ligament transection (ACLT) in rabbits. Using quantitative real-time PCR and ELISA to investigate the expression levels of MMP-1, MMP-3, MMP-13, and tissue inhibitors of metalloproteinase-1(TIMP-1) in IL-1β-induced rabbit chondrocytes, we showed that CGA inhibits the expression of these MMPs while increasing TIMP-1 expression, at both the mRNA and protein levels.

Effects of diallyl sulphide in chondrocyte and cartilage in experimental osteoarthritis in rabbit.

Diallyl sulphide (DAS) is known for its antioxidant, anticancer and detoxifying properties. The aim of this study was to investigate the effect of DAS on rabbit articular chondrocytes and cartilage in experimental osteoarthritis (OA) induced by anterior cruciate ligament transection (ACLT). DAS inhibited matrix metalloproteinase-1 (MMP-1), MMP-3 and MMP-13 expression in interleukin-1beta (IL-1β)-induced chondrocytes.

Apelin plays a catabolic role on articular cartilage: in vivo and in vitro studies.

Adipokines play key roles in the regulation of bone growth, obesity, diabetes mellitus type 2, and HIV infection. As a newly discovered hormone in the adipokine family, the precise role of apelin on articular cartilage metabolism is not yet clear. The aim of this study was to evaluate the role of apelin on articular cartilage.

Increased apelin serum levels and expression in human chondrocytes in osteoarthritic patients.

Apelin is a recently discovered hormone secreted by adipocytes. The aim of this study, therefore, was to evaluate the distribution of apelin in paired serum and synovial fluid (SF) of osteoarthritis (OA) patients, as compared to that in healthy controls, and to characterise the expression profile of apelin and its cognate receptor APJ in human chondrocytes. Apelin levels in serum and SF were analysed by enzyme-linked immunosorbent assay (ELISA).

Increased serum concentrations of visfatin and its production by different joint tissues in patients with osteoarthritis.

Background: The goal of this study was to investigate the distribution of visfatin in paired serum and synovial fluid (SF) samples from patients with osteoarthritis (OA), and in serum from healthy controls. In addition, we wished to determine the potential sources of visfatin in joint tissue.

Methods: Twenty-three patients with OA requiring total knee arthroplasty (TKA), 17 healthy subjects and ten donors requiring amputation were included in the study.