Division of Allergy, Immunology and Rheumatology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.
Division of Rheumatology, Immunology and Allergy, Department of Internal Medicine, Taipei Medical University Hospital, Taipei 11031, Taiwan.
Int J Mol Sci. 2022 Feb 26;23(5):2604. doi: 10.3390/ijms23052604.
Calcium pyrophosphate (CPP) deposition disease (CPPD) is a form of CPP crystal-induced arthritis. A high concentration of extracellular pyrophosphate (ePPi) in synovial fluid is positively correlated with the formation of CPP crystals, and ePPi can be upregulated by ankylosis human (ANKH) and ectonucleotide pyrophosphatase 1 (ENPP1) and downregulated by tissue non-specific alkaline phosphatase (TNAP). However, there is currently no drug that eliminates CPP crystals. We explored the effects of the histone deacetylase (HDAC) inhibitors (HDACis) trichostatin A (TSA) and vorinostat (SAHA) on CPP formation. Transforming growth factor (TGF)-β1-treated human primary cultured articular chondrocytes (HC-a cells) were used to increase ePPi and CPP formation, which were determined by pyrophosphate assay and CPP crystal staining assay, respectively. Artificial substrates thymidine 5'-monophosphate p-nitrophenyl ester (p-NpTMP) and p-nitrophenyl phosphate (p-NPP) were used to estimate ENPP1 and TNAP activities, respectively. The HDACis TSA and SAHA significantly reduced mRNA and protein expressions of ANKH and ENPP1 but increased TNAP expression in a dose-dependent manner in HC-a cells. Further results demonstrated that TSA and SAHA decreased ENPP1 activity, increased TNAP activity, and limited levels of ePPi and CPP. As expected, both TSA and SAHA significantly increased the acetylation of histones 3 and 4 but failed to block Smad-2 phosphorylation induced by TGF-β1. These results suggest that HDACis prevented the formation of CPP by regulating ANKH, ENPP1, and TNAP expressions and can possibly be developed as a potential drug to treat or prevent CPPD.
焦磷酸钙（CPP）沉积病（CPPD）是一种 CPP 晶体诱导的关节炎。关节滑液中细胞外焦磷酸（ePPi）浓度的升高与 CPP 晶体的形成呈正相关，而 ePPi 可以被锚定人类蛋白（ANKH）和核苷酸外切酶 1（ENPP1）上调，被组织非特异性碱性磷酸酶（TNAP）下调。然而，目前还没有消除 CPP 晶体的药物。我们探索了组蛋白去乙酰化酶（HDAC）抑制剂（HDACis）曲古抑菌素 A（TSA）和伏立诺他（SAHA）对 CPP 形成的影响。转化生长因子（TGF）-β1 处理的人原代培养关节软骨细胞（HC-a 细胞）被用于增加 ePPi 和 CPP 形成，分别通过焦磷酸酯测定和 CPP 晶体染色测定来确定。人工底物胸苷 5'-单磷酸 p-硝基苯酯（p-NpTMP）和对硝基苯磷酸（p-NPP）分别用于估计 ENPP1 和 TNAP 活性。HDACis TSA 和 SAHA 显著降低了 HC-a 细胞中 ANKH 和 ENPP1 的 mRNA 和蛋白表达，且呈剂量依赖性，同时增加了 TNAP 的表达。进一步的结果表明，TSA 和 SAHA 降低了 ENPP1 的活性，增加了 TNAP 的活性，并限制了 ePPi 和 CPP 的水平。正如预期的那样，TSA 和 SAHA 均显著增加了组蛋白 3 和 4 的乙酰化，但未能阻止 TGF-β1 诱导的 Smad-2 磷酸化。这些结果表明，HDACis 通过调节 ANKH、ENPP1 和 TNAP 的表达来防止 CPP 的形成，并且可能被开发为治疗或预防 CPPD 的潜在药物。
