X F Li1, Z Zhang, X D Li, T B Wang, H N Zhang. 1. Department of Joint Surgery, the Affiliated Hospital of Qingdao University, Qingdao 266000, China.
Abstract
OBJECTIVE: To invstigate the mechanism of new mechanically-activated cation channel protein (Piezo1) can cause the apoptosis of the human chondrocytes under compressive loading, using a Flexercell unit by activating classical Mitogen-activated protein kinase (MAPK) signal pathyway(ERK1/2). METHODS: Primary human chondrocytes were isolated, cultured, and then subjected to the static compressive loading for 0, 2, 12, 24, 48 h, respectively.The expressions of Piezo1 and the ERK1/2 were assessed by reverse transcription-polymerase chain reaction(PT-PCR), as well as the apoptosis gene B cell lymphoma/leukemia-2(Bcl-2) Bel-associated X protein(Bax). In addition, Piezo1inhibitor, Grammostola spatulata mechanotoxin 4(GsMTx4), was used to block Piezo1, served as a positive control.The immunofluorescence was used to locate the expression of Piezo1 protein and ERK1/2.AnnexinV-PI was used to detect the apoptosis of chondrocytes. RESULTS: The expression of the Piezo1 in chondrocytesis was weak, the 12 h group was significant increased(0.198 1 vs 0.021 4, P<0.05), the 24 h group was the highest expression while the expression of the 48 h group was lower than the 24 h group, as well as the ERK1/2, Bcl-2 and caspase3.The result of AV-PI had shown that the 2 h group had increased early stage of apoptosis.The 12 h group had increased late stage of apoptosis, and the 24 h group's apoptotic rate was the highest, while the apoptotic rate of the 48 h group was lower than the 24 h group(0.497 1 vs 0.743 1, q=0.035 9). The GsMTx4 could inhibit the late stage of apoptosis, and the location of the Piezo1 was expressed in the nucleus and cytoplasm of the chondrocytes. CONCLUSIONS: Piezo1 plays an important role in the apoptosis of the human chondrocyte through the classic MAPK/ERK1/2 signal pathway.
OBJECTIVE: To invstigate the mechanism of new mechanically-activated cation channel protein (Piezo1) can cause the apoptosis of the human chondrocytes under compressive loading, using a Flexercell unit by activating classical Mitogen-activated protein kinase (MAPK) signal pathyway(ERK1/2). METHODS: Primary human chondrocytes were isolated, cultured, and then subjected to the static compressive loading for 0, 2, 12, 24, 48 h, respectively.The expressions of Piezo1 and the ERK1/2 were assessed by reverse transcription-polymerase chain reaction(PT-PCR), as well as the apoptosis gene B cell lymphoma/leukemia-2(Bcl-2) Bel-associated X protein(Bax). In addition, Piezo1inhibitor, Grammostola spatulata mechanotoxin 4(GsMTx4), was used to block Piezo1, served as a positive control.The immunofluorescence was used to locate the expression of Piezo1 protein and ERK1/2.AnnexinV-PI was used to detect the apoptosis of chondrocytes. RESULTS: The expression of the Piezo1 in chondrocytesis was weak, the 12 h group was significant increased(0.198 1 vs 0.021 4, P<0.05), the 24 h group was the highest expression while the expression of the 48 h group was lower than the 24 h group, as well as the ERK1/2, Bcl-2 and caspase3.The result of AV-PI had shown that the 2 h group had increased early stage of apoptosis.The 12 h group had increased late stage of apoptosis, and the 24 h group's apoptotic rate was the highest, while the apoptotic rate of the 48 h group was lower than the 24 h group(0.497 1 vs 0.743 1, q=0.035 9). The GsMTx4 could inhibit the late stage of apoptosis, and the location of the Piezo1 was expressed in the nucleus and cytoplasm of the chondrocytes. CONCLUSIONS:Piezo1 plays an important role in the apoptosis of the human chondrocyte through the classic MAPK/ERK1/2 signal pathway.
Authors: K M Lawrence; R C Jones; T R Jackson; R L Baylie; B Abbott; B Bruhn-Olszewska; T N Board; I C Locke; S M Richardson; P A Townsend Journal: Sci Rep Date: 2017-07-11 Impact factor: 4.379