Proinflammatory Effects of IL-1β Combined with IL-17A Promoted Cartilage Degradation and Suppressed Genes Associated with Cartilage Matrix Synthesis In Vitro

Abstract

Combinations of IL-1β and other proinflammatory cytokines reportedly promote the severity of arthritis. We aimed to investigate the effects of IL-1β combined with IL-17A on cartilage degradation and synthesis in in vitro models. Cartilage explant degradation was determined using sulfated glycosaminoglycans (S-GAGs) levels, matrix metalloproteinase (MMP13) gene expression, uronic acid, and collagen contents. Cell morphology and accumulation of proteoglycans were evaluated using hematoxylin-eosin and safranin O staining, respectively. In the pellet culture model, expressions of cartilage-specific anabolic and catabolic genes were evaluated using real-time qRT-PCR. Early induction of MMP13 gene expression was found concomitantly with significant S-GAGs release. During the prolonged period, S-GAGs release was significantly elevated, while MMP-13 enzyme levels were persistently increased together with the reduction of the cartilaginous matrix molecules. The pellet culture showed anabolic gene downregulation, while expression of the proinflammatory cytokines, mediators, and MMP13 genes were elevated. After cytokine removal, these effects were restored to nearly basal levels. This study provides evidence that IL-1β combined with IL-17A promoted chronic inflammatory arthritis by activating the catabolic processes accompanied with the suppression of cartilage anabolism. These suggest that further applications, which suppress inflammatory enhancers, especially IL-17A, should be considered as a target for arthritis research and therapy.

An Evidence-Based Systematic Review of Human Knee Post-Traumatic Osteoarthritis (PTOA): Timeline of Clinical Presentation and Disease Markers, Comparison of Knee Joint PTOA Models and Early Disease Implications

“…Other reviews [ 139 , 140 ] have well described how articular cartilage explant models have used various types of injurious compression protocols to simulate mechanical injury and have demonstrated that, despite differences in protocols, these models show that they similarly and successfully induce the clinically observed pathologies following trauma to the knee joint. Hence, the mechanically-induced injury of articular cartilage leads to a significant increase in chondrocyte death, ECM loss, expression of matrix-degrading enzymes and a decrease in the COL2 gene and, to some extent, an increase in inflammatory cytokines even in the absence of inflammatory cells, such as macrophages [ 141 , 142 , 143 , 144 , 145 , 146 , 147 , 148 , 149 , 150 , 151 , 152 , 153 ]. Some studies have used a combination of mechanical injury and inflammatory cytokine treatment, typically using IL-1α, IL-1β, TNF-α, IL-17, or the combination of TNF-α/IL-6/sIL-6R [ 143 , 144 , 145 , 146 , 148 , 152 , 154 ] to mirror trauma and the presence of cytokines that are significantly present with the injured knee.…”

“…Articular cartilage explant and in vitro chondrocyte studies, using cells or tissue derived from either OA or healthy sources have shown that IL-1α treatment alone is capable of increasing production of MMP-1, 3, 9 and -13 and ADAMTS-4 and -5, decreasing proteoglycan synthesis and increasing the loss of sGAG [ 144 , 148 , 149 , 155 , 156 , 157 ], while IL-1β alone is capable of enhancing NO production, collagenase activity, IL-6, IL-8, LIF, MMPs (MMP-1, -3, -13, -7, -9, -12), complement components, chemokines as well as aggrecan release; and inhibiting type II collagen, NF-ĸB binding activation and phosphor-Smad2/3 [ 69 , 147 , 152 , 158 , 159 , 160 , 161 , 162 , 163 , 164 ]. These studies, as well as animal models, showed that IL-1β is involved in inflammation and cartilage degradation.…”

“…Many IL-17 effects can be reversed by the removal of e.g., IL1-β and IL-17A from the media [ 152 ] or by pre-treatment with an IL-17 receptor antibody [ 175 ], dexamethasone, or kinase inhibitors [ 172 , 176 ]. Secukinumab, a human monoclonal antibody that binds to IL-17A, is already used clinically to treat arthritis-associated symptoms and joint disease damage in ankylosing spondylitis and psoriatic arthritis, further supporting the antagonistic role of IL-17A in joint disease [ 184 ].…”

“…The * indicates the corresponding model that showed an increase of that marker in the serum (S). ( b ) Ex vivo cartilage explant models using non-0A (healthy) tissue showing the effects of blood-induced injury [ 76 , 77 , 78 ], mechanical injury using a single injurious compression without the addition of any pro-inflammatory cytokines [ 93 , 141 , 143 , 144 , 206 , 207 ], inflammatory cytokines IL-1α alone [ 144 , 149 , 155 , 156 ] or combined with injury* [ 144 , 148 ], IL-1β alone [ 147 , 152 ], TNF-α alone [ 144 , 145 , 146 , 147 ] or combined with injury* [ 143 , 144 , 145 , 146 ], IL-17A alone [ 150 ], and TNF-α/IL-6/sIL-6R alone [ 143 , 146 , 154 ] or combined with injury* [ 144 , 148 , 154 ]. (c) In vitro chondrocyte models using cells isolated from non-OA (healthy) cartilage tissue showing the effects of IL-1α [ 157 ], IL-1β [ 159 , 160 ], TNF-α [ 166 , 167 ], IL-17 or IL-17F [ 172 , 175 ], IL-6 or IL-8 [ 160 ], and LIF [ 160 , 175 ].…”

Post-treatment of hyaluronan to decrease the apoptotic effects of carprofen in canine articular chondrocyte culture

“…In the present study, Comb48 seemed to enhance the expression of these anabolic genes, which may suggest the benefit of HA when combined with CAR. Nevertheless, we have suggested that chondrocytes be more deeply investigated for further use in 3D culture models, such as those involving pellet or scaffold cultures (Kongdang et al, 2019).…”