Epigallocatechin 3-gallate inhibits the plasma membrane Ca-ATPase: effects on calcium homeostasis.

Flavonoids are natural compounds responsible for the health benefits of green tea. Some of the flavonoids present in green tea are catechins, among which are: epigallocatechin, epicatechin-3-gallate, epicatechin, catechin and epigallocatechin-3-gallate (EGCG). The latter was found to induce apoptosis, reduce reactive oxygen species, in some conditions though in others it acts as an oxidizing agent, induce cell cycle arrest, and inhibit carcinogenesis.

Selectivity of plasma membrane calcium ATPase (PMCA)-mediated extrusion of toxic divalent cations in vitro and in cultured cells.

In the recent years, the toxicity of certain divalent cations has been associated with the alteration of intracellular Ca homeostasis. Among other mechanisms, these cations may affect the functionality of certain Ca-binding proteins and/or Ca pumps. The plasma membrane calcium pump (PMCA) maintains Ca homeostasis in eukaryotic cells by mediating the efflux of this cation in a process coupled to ATP hydrolysis.