Vesela Barbora, Kratochvilova Adela, Svandova Eva, Benes Petr, Rihova Kamila, Poliard Anne, Matalova Eva
Laboratory of Odontogenesis and Osteogenesis, Institute of Animal Physiology and Genetics, Academy of Sciences, Brno, Czechia.
Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia.
Front Cell Dev Biol. 2020 Oct 15;8:589136. doi: 10.3389/fcell.2020.589136. eCollection 2020.
Caspases are evolutionary conserved proteases traditionally known as participating in apoptosis and inflammation but recently discovered also in association with other processes such as proliferation or differentiation. This investigation focuses on caspase-12, ranked among inflammatory caspases but displaying other, not yet defined functions. A screening analysis pointed to statistically significant ( < 0.001) increase in expression of caspase-12 in a decisive period of mandibular bone formation when the original mesenchymal condensation turns into vascularized bone tissue. Immunofluorescence analysis confirmed the presence of caspase-12 protein in osteoblasts. Therefore, the osteoblastic cell line MC3T3-E1 was challenged to investigate any impact of caspase-12 on the osteogenic pathways. Pharmacological inhibition of caspase-12 in MC3T3-E1 cells caused a statistically significant decrease in expression of some major osteogenic genes, including those for alkaline phosphatase, osteocalcin and Phex. This downregulation was further confirmed by an alkaline phosphatase activity assay and by a siRNA inhibition approach. Altogether, this study demonstrates caspase-12 expression and points to its unknown physiological engagement in bone cells during the course of craniofacial development.
半胱天冬酶是进化保守的蛋白酶，传统上认为其参与细胞凋亡和炎症，但最近也发现其与增殖或分化等其他过程有关。本研究聚焦于半胱天冬酶-12，它属于炎性半胱天冬酶，但具有其他尚未明确的功能。一项筛选分析指出，在下颌骨形成的关键时期，即原始间充质凝聚转变为血管化骨组织时，半胱天冬酶-12的表达有统计学意义的显著增加（<0.001）。免疫荧光分析证实成骨细胞中存在半胱天冬酶-12蛋白。因此，对成骨细胞系MC3T3-E1进行研究，以探讨半胱天冬酶-12对成骨途径的任何影响。对MC3T3-E1细胞中半胱天冬酶-12的药理学抑制导致一些主要成骨基因的表达有统计学意义的显著下降，包括碱性磷酸酶、骨钙素和Phex的基因。碱性磷酸酶活性测定和小干扰RNA抑制方法进一步证实了这种下调。总之，本研究证明了半胱天冬酶-12的表达，并指出其在颅面发育过程中在骨细胞中未知的生理作用。
