Organogermanium: Potential beneficial effects on the cardiovascular system

Abstract

Organogermanium, especially poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132), has been known to enhance immune-modulatory activities. However, the in vivo and in vitro evidence accumulated over the last 20 years reveals that Ge-132 has unique but underappreciated multi-functional properties that have a potential positive effect for the cardiovascular system. A hydrolysate of Ge-132, monomeric 3-(trihydroxygermyl)propanoic acid, forms a complex with a vicinal diol structure (i.e., having two adjacent hydroxyl groups such as the cis-diol and catechol groups) that exists in ribose (e.g., adenosine triphosphate), catecholamine (e.g., adrenaline), and saccharide (e.g., glucose). Additionally, Ge-132 enhances macrophage phagocytosis and the heme catabolic pathway by upregulating key enzymes that are responsible for producing cytoprotective molecules such as biliverdin and bilirubin during the process. These multi-functional properties exert pleiotropic physiological effects after an oral intake of Ge-132 such as anti-oxidation, anti-inflammation, anti-hypertensive, anti-glycation, and erythrocyte lifecycle enhancement, all of which appear to assist the cardiovascular system. Of those effects, the effects on the lifecycle of erythrocyte may have an important implication for maintaining optimal vascular function, augmenting the availability of oxygen by enhancing the elimination of senescent, and damaged erythrocytes as well as promoting erythropoiesis. Human studies are warranted to determine whether these beneficial effects observed in previous studies are translated into humans.

Keywords: artery; blood pressure; diabetes; erythrocyte; inflammation; oxidative stress.

FIGURE 1

Schematic diagram of the complex formation reaction between the hydrolysate of Ge‐132, THGP, and vicinal diol compounds. THGP reacts with vicinal diol compounds through a dehydration reaction via the Ge‐OH group in the molecule, forming stable complexes in a neutral pH aqueous solution. THGP, 3‐(trihydroxygermyl)propanoic acid.

FIGURE 2

Schematic representation of erythrocyte lifecycle and heme catabolic pathway. See the main text for details. “*” Denotes a site where Ge‐132 may act in the pathway. HO‐1, heme oxygenase 1; UGT1A1, uridine diphosphate glucuronyltransferase 1A1. The figure was created with BioRender.com.