Allium sativum L. is a molecule of garlic defense (Allium sativum L.). It is a natural compound present in garlic that contains sulfur and has many different biological properties. It is responsible for the typical smell and taste of freshly cut or crumpled garlic. It is believed that most of the effects of allicin are mediated via redox mechanism. Allicin has a variety of health-promoting properties, such as cholesterol and blood pressure lowering effects that are advantageous to the cardiovascular system.
Allicin and cardiovascular diseases
Cardiovascular disorders are complex because they are influenced by several factors. In particular, general oxidative events such as oxidation of low-density lipid protein (LDL) often correlate smear with atherosclerosis. Although allicin is chemically an oxidant, it acts in smaller doses as an antioxidant at the physiological level. This observation can be explained by the fact that mild oxidative conditions induce the expression of so-called detoxifying enzymes, for example, by the activation of redox-sensitive enzymes and increase protection against additional and stronger oxidative insults.
An example for the oxidation of a redox-sensitive transcription factor by the allicin electrophile is the Nrf2/Keap1 system that regulates the expression of various antioxidant enzymes (among others from glutathione biosynthesis). The fact that allicin can induce the Nrf2/Keap1 system has been demonstrated in several studies. It is necessary to mention that the activation of Nrf2 by allicin is not only important in the context of cardiovascular diseases, but also for several other health-related events, such as neurodegenerative diseases.
In this context, allicin has been demonstrated to attenuate age-related cognitive effects and memory deficits by activating the Nrf2 system. According to the so-called “LDL receptor hypothesis”, cholesterol is a central factor for atherosclerosis, possibly due to the attraction and activation of macrophages by oxidized LDL, causing plaques in the arteries. Thus, it is assumed that cholesterol is a risk factor for atherosclerosis and therefore for ischemic disorders. One strategy to interfere with the progression of plaque deposition in the arteries is the reduction of endogenous cholesterol biosynthesis, commonly by the application of statins. Allicin also shows the ability to suppress cholesterol biosynthesis, which is attributed to inhibition of enzymes squaleno-monooxygenase and acetyl-CoA synthesis.
Immunomodulatory activity of allicin
Allicin is a strong antimicrobial agent and therefore, at least in vitro, is a potent antibiotic. In addition to this direct impact on pathogens, another facet of their activity is the influence on the endogenous immune system. Allicin stimulates the activity of immune cells, this results in a strengthened defense against pathogens and the suppression of immune processes. Therefore, it may be interesting in relation to allergies or autoimmune disorders.
Allicin inhibits the migration of neutrophilic granulocytes to epithelium, which is a crucial process during inflammation. In addition, it acts on T lymphocytes by inhibition of Chemotaxis induced by SDF1α-chemokine and this effect is correlated with an impairment in the dynamics of the actin cytoskeleton. Thus, it is also demonstrated that allicin inhibits transendothelial migration of neutrophils.
Allicin is a reactive sulfur and undergoes a redox reaction with thiol groups in glutathione and proteins that is considered essential for its biological activity. Allicin is physiologically active in microbial, plant and mammalian cells. It can inhibit the proliferation of bacteria and fungi or kill cells immediately. In addition, it promotes cardiovascular health and immunomodulatory activity.
Bioactive compounds for skin health
Watch the video on Science Play with Marcelo Carvalho:
Action of bioactive compounds in the central nervous system
Article: Allicin – Borlinghaus J, Albrecht F, Gruhlke MC, Nwachukwu ID, AJ Slusarenko. Allicin: chemistry and biological properties. Molecules. 2014;19(8):12591-12618. Published 2014 Aug 19. Doi:10.3390/molecules190812591