Bradykinin regulates cell growth and migration in cultured human cardiac c-Kit+ progenitor cells

Abstract

Bradykinin is a well-known endogenous vasoactive peptide. The present study investigated the bradykinin receptor expression in human cardiac c-Kit+ progenitor cells and the potential role of bradykinin in regulating cell cycling progression and mobility. It was found that mRNA and protein of bradykinin type 2 receptors, but not bradykinin type 1 receptors, were abundant in cultured human cardiac c-Kit+ progenitor cells. Bradykinin (1-10 nM) stimulated cell growth and migration in a concentration-dependent manner. The increase of cell proliferation was related to promoting G0/G1 transition into G2/M and S phase. Western blots revealed that bradykinin significantly increased pAkt and pERK1/2 as well as cyclin D1, which were countered by HOE140 (an antagonist of bradykinin type 2 receptors) or by silencing bradykinin type 2 receptors. The increase of pAkt, pERK1/2 and cyclin D1 by bradykinin was prevented by the PI3K inhibitor Ly294002, the PLC inhibitors U73122 and neomycin, and/or the PKC inhibitor chelerythrine and the MAPK inhibitor PD98059. Our results demonstrate the novel information that bradykinin promotes cell cycling progression and migration in human cardiac c-Kit+ progenitor cells via activating PI3K, PLC, PKC, cyclin D1, pERK1/2, and pAkt.

Bradykinin‐mediated Ca2+ signalling regulates cell growth and mobility in human cardiac c‐Kit+ progenitor cells

“…In our previous study, bradykinin at 10 nmol L −1 remarkably stimulates cell growth and migration 10. We therefore utilize the 10 nmol L −1 bradykinin in this study to investigate whether the stimulation of cell growth and migration is linked to Ca 2+ signalling induced by bradykinin.…”

“…We have recently demonstrated that SOCE channel participates in regulating cell growth and migration,13 and bradykinin promotes cell cycling progression and mobility in cultured human cardiac c‐Kit + progenitor cells 10. To investigate whether the stimulation of cell cycling progression and mobility by bradykinin is related to Ca 2+ signalling.…”

“…Reverse transcription‐polymerase chain reaction was employed to determine mRNA expression in cells with silenced IP3Rs, TRPC channels or SOCE channels for siRNA efficacy as described previously 10, 13. Briefly, total RNA was extracted from human cardiac c‐Kit + progenitor cells transfected with corresponding siRNA for 48 hours using TRIzol reagent.…”

“…Reverse transcription-polymerase chain reaction was employed to determine mRNA expression in cells with silenced IP3Rs, TRPC channels or SOCE channels for siRNA efficacy as described previously. 10,13 Briefly, total RNA was extracted from human cardiac c-Kit + progenitor cells transfected with corresponding siRNA for 48 hours using TRIzol reagent. The amount of total RNA was quantified by spectrophotometry, and reverse transcription reaction was performed using 2 lg of total RNA to transcribe into complementary DNA with Advantage â RTfor-PCR Kit (Takara biotech Co., Ltd, Dalian, China) following manufacturer's instruction.…”

“…9 Our recent study demonstrated that the endogenous peptide bradykinin promotes cell cycling progression and migration via activating PI3K, phospholipase C (PLC), pAkt, pERK1/2 and cyclin D1 in human cardiac c-Kit + progenitor cells. 10 However, it is unknown whether bradykinin-induced cycle progression and migration are related to Ca 2+ signalling in human cardiac c-Kit + progenitor cells. This study was therefore designed to investigate the detailed molecular mechanisms of whether/how Ca 2+ signalling-related channels/receptors are involved in bradykinininduced increase in cell growth and migration in human cardiac c-Kit + progenitor cells with multiple biochemical/molecular biological approaches.…”