Transforming growth factor-β receptor 1: An intervention target for genetic poor cartilage quality induced by prenatal dexamethasone exposure

The physiological metabolite α-ketoglutarate ameliorates osteoarthritis by regulating mitophagy and oxidative stress

“…Primary human articular chondrocytes were extracted from normal lateral cartilage of patients that underwent total knee replacement surgery. Briefly [ 2 ], cartilage was exposed to type II collagenase (2 mg/mL, Invitrogen™, USA) at 37 °C for 8 h after shearing. Then, chondrocytes were harvested after centrifugation at 500 g for 5 min and seeded with DMEM/F-12 medium and 10% FBS with 100 mg/ml streptomycin and 100 U/ml penicillin.…”

“…For IF [ 2 ], after 24 h of treatment, the cells in confocal dishes were fixed in 4% formaldehyde for 20 min. 0.5% Triton X-100 was added to the dishes and washed with PBS three times.…”

“…Total RNA was extracted from articular cartilage tissues/chondrocytes by TRIzol reagent [ 2 ]. Briefly, 1 ml TRIzol and 200 μl chloroform were added to the samples in 1.5 ml EP tubes.…”

“…The samples were then dehydrated before paraffin embedding. 5 μm-thick sagittal slices were prepared for Safranin O-fast green staining as described previously [ 2 ]. Briefly, after being deparaffinized to water (the specimens were sequentially placed in xylene I−xylene II−anhydrous ethanol I−anhydrous ethanol II−90% alcohol−85% alcohol−75% alcohol and then washed with water), sections were stained with Fast green (G1053-2, Servicebio™, Wuhan, China) for 5 min, followed by Safranin O (G1053-1, Servicebio™, Wuhan, China) for 5 s before being quickly dehydrated with absolute ethanol.…”

“…Osteoarthritis (OA) is a prevalent chronic and crippling disease characterized by cartilage destruction, osteophyte formation, and joint pain [ 1 , 2 ]. As of 2015, about 237 million people were suffering from OA worldwide, accounting for 3.3% of the total population [ 3 , 4 ].…”