Department of Pediatrics, McGovern Medical School at UTHealth Houston, Houston, TX 77030, USA.
School of Dentistry, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA.
Int J Mol Sci. 2023 Feb 14;24(4):3845. doi: 10.3390/ijms24043845.
Mutations in cartilage oligomeric matrix protein (COMP) causes protein misfolding and accumulation in chondrocytes that compromises skeletal growth and joint health in pseudoachondroplasia (PSACH), a severe dwarfing condition. Using the MT-COMP mice, a murine model of PSACH, we showed that pathological autophagy blockage was key to the intracellular accumulation of mutant-COMP. Autophagy is blocked by elevated mTORC1 signaling, preventing ER clearance and ensuring chondrocyte death. We demonstrated that resveratrol reduces the growth plate pathology by relieving the autophagy blockage allowing the ER clearance of mutant-COMP, which partially rescues limb length. To expand potential PSACH treatment options, CurQ+, a uniquely absorbable formulation of curcumin, was tested in MT-COMP mice at doses of 82.3 (1X) and 164.6 mg/kg (2X). CurQ+ treatment of MT-COMP mice from 1 to 4 weeks postnatally decreased mutant COMP intracellular retention, inflammation, restoring both autophagy and chondrocyte proliferation. CurQ+ reduction of cellular stress in growth plate chondrocytes dramatically reduced chondrocyte death, normalized femur length at 2X 164.6 mg/kg and recovered 60% of lost limb growth at 1X 82.3 mg/kg. These results indicate that CurQ+ is a potential therapy for COMPopathy-associated lost limb growth, joint degeneration, and other conditions involving persistent inflammation, oxidative stress, and a block of autophagy.
软骨寡聚基质蛋白 (COMP) 的突变导致蛋白错误折叠和在软骨细胞中的积累,从而损害假性软骨发育不全症 (PSACH) 中的骨骼生长和关节健康,PSACH 是一种严重的侏儒症。使用 MT-COMP 小鼠,即 PSACH 的一种鼠模型,我们表明病理性自噬阻断是突变型-COMP 细胞内积累的关键。自噬被升高的 mTORC1 信号阻断,阻止内质网清除并确保软骨细胞死亡。我们证明白藜芦醇通过缓解自噬阻断减轻生长板病理,从而允许 ER 清除突变型-COMP,部分挽救肢体长度。为了扩大潜在的 PSACH 治疗选择,CurQ+,姜黄素的独特可吸收配方,在 MT-COMP 小鼠中在 82.3(1X)和 164.6 mg/kg(2X)的剂量下进行了测试。CurQ+从出生后 1 至 4 周对 MT-COMP 小鼠的治疗降低了突变型 COMP 的细胞内保留,炎症,恢复了自噬和软骨细胞增殖。CurQ+减少生长板软骨细胞中的细胞应激,极大地减少了软骨细胞死亡,使 2X 164.6 mg/kg 的股骨长度正常化,并使 1X 82.3 mg/kg 的肢体生长恢复 60%。这些结果表明 CurQ+是治疗 COMPopathy 相关的肢体生长损失、关节退化和其他涉及持续炎症、氧化应激和自噬阻断的病症的潜在疗法。