tofacitinib and Osteoarthritis

Osteoarthritis (OA) is a multifactorial disease of the whole joint that has a complex pathogenesis. There is currently no cure for OA. Tofacitinib is a broad JAK inhibitor that can have an anti-inflammatory effect. The objective of this study was to investigate the effect of tofacitinib on the cartilage extracellular matrix in OA and determine whether tofacitinib exerts a protective effect by inhibiting the JAK1/STAT3 signaling pathway and upregulating autophagy in chondrocytes. We investigated the expression profile of OA in vitro by exposing SW1353 cells to interleukin-1β (IL-1β), and induced OA in vivo using the modified Hulth method in rats. We found that IL-1β promoted the expression of OA-related matrix metalloproteinases (MMP3 and MMP13), reduced the expression of collagen II, reduced the expression of beclin1 and LC3-II/I, and promoted the accumulation of p62 in SW1353 cells. Tofacitinib attenuated IL-1β-stimulated changes in MMPs and collagen II and restored autophagy. In IL-1β-stimulated SW1353 cells, the JAK1/STAT3 signaling pathway was activated. Tofacitinib inhibited the IL-1β-stimulated expression of p-JAK1 and p-STAT3 and prevented translocation of p-STAT3 to the nucleus. In the rat model of OA, tofacitinib reduced articular cartilage degeneration by delaying cartilage extracellular matrix degradation and increasing chondrocyte autophagy. Our study demonstrates that chondrocyte autophagy was impaired in experimental models of OA. Tofacitinib reduced the inflammatory response and restored the damaged autophagic flux in OA.

Topics: Animals; Autophagy; Cartilage, Articular; Chondrocytes; Collagen; Interleukin-1beta; Janus Kinase Inhibitors; Osteoarthritis; Rats

Osteoarthritis (OA), a common articular bone degenerative disease, is exacerbated by proinflammatory cytokine signaling. Mounting evidence suggests that epigenetic modifiers, namely microRNAs (miRs), are dysregulated in articular chondrocytes (ACs) during OA.. An initial database search led to the identification of miR-149-5p, which was downregulated in clinical OA samples and contributed to chronic inflammation, by increasing TNF-α/IL-6 signaling within the synovium, and OA progression.. We overexpressed miR-149-5p in the human chondrocyte cell lines C20A4 and C28/I2 to examine its role in chondrocyte hypertrophy and osteoclastogenesis and found a significant decrease in IL-6 expression, an increase in SOX9 expression, and a reduction in chondrocyte hypertrophy. We evaluated the therapeutic effects of tofacitinib (JAK inhibitor) by suppressing inflammation and restoring miR-149-5p expression. Tofacitinib-treated C20A4 and C28/I2 cells had a significantly lower expression of JAK/IL-6/TNF-α and an increased level of miR-149-5p. Notably, tofacitinib treatment reduced AC hypertrophy and secretion of RANKL and IL-6. Finally, an OA mouse model was used to evaluate the therapeutic potential of tofacitinib. Intra-articular injection of tofacitinib significantly lowered arthritis scores and bone degradation in treated mice compared with their control counterparts.. We show for the first time that tofacitinib suppresses the expression level of JAK1/TNF-α/IL-6 by upregulating miR-149-5p level. Our findings revealed the functional association between proinflammatory JAK1/TNF-α/IL-6 signaling and ACs development and highlight the therapeutic potential of tofacitinib in OA.

Topics: Animals; Chondrocytes; Interleukin-6; Janus Kinase 1; Janus Kinase Inhibitors; Mice; MicroRNAs; Osteoarthritis; Piperidines; Pyrimidines; Tumor Necrosis Factor-alpha

Currently, there are no disease-modifying osteoarthritis drugs (DMOADs) approved for osteoarthritis. It is hypothesized that a subtype of OA may be driven by inflammation and may benefit from treatment with anti-inflammatory small molecule inhibitors adopted from treatments of rheumatoid arthritis. This study aimed to investigate how small molecule inhibitors of intracellular signaling modulate cartilage degradation and formation as a pre-clinical model for structural effects.. Bovine cartilage explants were cultured with oncostatin M (OSM) and tumour necrosis factor α (TNF-α) either alone or combined with the small molecule inhibitors: SB203580 (p38 inhibitor), R406 (Spleen tyrosine kinase (Syk) inhibitor), TPCA-1 (Inhibitor of κB kinase (Ikk) inhibitor), or Tofacitinib (Tofa) (Janus kinases (Jak) inhibitor). Cartilage turnover was assessed with the biomarkers of degradation (AGNx1 and C2M), and type II collagen formation (PRO-C2) using ELISA. Explant proteoglycan content was assessed by Safranin O/Fast Green staining.. R406, TPCA-1 and Tofa reduced the cytokine-induced proteoglycan loss and decreased AGNx1 release 3.7-, 43- and 32-fold, respectively. SB203580 showed no effect. All inhibitors suppressed C2M at a concentration of 3 µM. TPCA-1 and Tofa increased the cytokine reduced PRO-C2 3.5 and 3.7-fold, respectively.. Using a pre-clinical model we found that the inhibitors TPCA-1 and Tofa inhibited cartilage degradation and rescue formation of type II collagen under inflammatory conditions, while R406 and SB203580 only inhibited cartilage degradation, and SB203580 only partially. These pre-clinical data suggest that TPCA-1 and Tofa preserve and help maintain cartilage ECM under inflammatory conditions and could be investigated further as DMOADs for inflammation-driven osteoarthritis.

Topics: Amides; Animals; Cartilage, Articular; Cattle; Chondrocytes; Collagen Type II; Extracellular Matrix Proteins; Imidazoles; Osteoarthritis; Oxazines; Piperidines; Proteoglycans; Pyridines; Pyrimidines; Pyrroles; Thiophenes

To rescue chondrogenic differentiation of human mesenchymal stem cells (hMSCs) in osteoarthritic conditions by inhibition of protein kinases.. hMSCs were cultured in pellets. During early chondrogenic differentiation, these were exposed to osteoarthritic synovium-conditioned medium (OAS-CM), combined with the Janus kinase (JAK)-inhibitor tofacitinib and/or the transforming growth factor β-activated kinase 1 (TAK1)-inhibitor oxozeaenol. To evaluate effects on chondrogenesis, the glycosaminoglycan (GAG) content of the pellets was measured at the time that chondrogenesis was manifest in control cultures. Moreover, mRNA levels of matrix molecules and enzymes were measured during this process, using real-time polymerase chain reaction (RT-PCR). Initial experiments were performed with hMSCs from a fetal donor, and results of these studies were confirmed with hMSCs from adult donors.. Exposure to OAS-CM resulted in pellets with a much lower GAG content, reflecting inhibited chondrogenic differentiation. This was accompanied by decreased mRNA levels of aggrecan, type II collagen, and Sox9, and increased levels of matrix metalloproteinase (MMP)1, MMP3, MMP13, ADAMTS4, and ADAMTS5. Both tofacitinib (JAK-inhibitor) and oxozeaenol (TAK1 inhibitor) significantly increased the GAG content of the pellets in osteoarthritis (OA)-like conditions. The combination of both protein kinase inhibitors showed an additive effect on GAG content. In agreement with this, in the presence of OAS-CM, both tofacitinib and oxozeaenol increased mRNA expression of sox9. The expression of aggrecan and type II collagen was also up-regulated, but this only reached significance for aggrecan after TAK1 inhibition. Both inhibitors decreased the mRNA levels of MMP1, 3, and 13 in the presence of OAS-CM. Moreover, oxozeaenol also significantly down-regulated the mRNA levels of aggrecanases ADAMTS4 and ADAMTS5. When combined, the inhibitors caused additive reduction of OA-induced MMP1 mRNA expression. Counteraction of OAS-CM-induced inhibition of chondrogenesis by these protein kinase inhibitors was confirmed with hMSCs of two different adult donors. Both tofacitinib and oxozeaenol significantly improved GAG content in cell pellets from these adult donors.. Tofacitinib and oxozeaenol partially prevent the inhibition of chondrogenesis by factors secreted by OA synovium. Their effects are additive. This indicates that these protein kinase inhibitors can potentially be used to improve cartilage formation under the conditions occurring in osteoathritic, or otherwise inflamed, joints.

Topics: Adult; Cartilage, Articular; Cell Differentiation; Chondrogenesis; Fetus; Humans; Janus Kinases; MAP Kinase Kinase Kinases; Mesenchymal Stem Cells; Osteoarthritis; Piperidines; Protein Kinase Inhibitors; Pyrimidines; Pyrroles; Time Factors; Zearalenone

Topics: Acetates; Antirheumatic Agents; Arthritis, Rheumatoid; Chondroitin Sulfates; Clinical Trials as Topic; Drug Therapy, Combination; Humans; Osteoarthritis; Piperidines; Pyrimidines; Pyrroles