Citrus bergamia Risso Elevates Intracellular Ca2+ in Human Vascular Endothelial Cells due to Release of Ca2+ from Primary Intracellular Stores

摘要

The purpose of the present study is to examine the effects of essential oil of Citrus bergamia Risso (bergamot, BEO) on intracellular Ca²⁺ in human umbilical vein endothelial cells. Fura-2 fluorescence was used to examine changes in intracellular Ca²⁺ concentration [Ca²⁺]i . In the presence of extracellular Ca²⁺, BEO increased [Ca²⁺]i , which was partially inhibited by a nonselective Ca²⁺ channel blocker La³⁺. In Ca²⁺-free extracellular solutions, BEO increased [Ca²⁺]i in a concentration-dependent manner, suggesting that BEO mobilizes intracellular Ca²⁺. BEO-induced [Ca²⁺]i increase was partially inhibited by a Ca²⁺-induced Ca²⁺ release inhibitor dantrolene, a phospholipase C inhibitor , and an inositol 1,4,5-triphosphate (IP3)-gated Ca²⁺ channel blocker, 2-aminoethoxydiphenyl borane (2-APB). BEO also increased [Ca²⁺]i in the presence of carbonyl cyanide m-chlorophenylhydrazone, an inhibitor of mitochondrial Ca²⁺ uptake. In addition, store-operated Ca²⁺ entry (SOC) was potentiated by BEO. These results suggest that BEO mobilizes Ca²⁺ from primary intracellular stores via Ca²⁺-induced and IP3-mediated Ca²⁺ release and affect promotion of Ca²⁺ influx, likely via an SOC mechanism.