Beneficial Effects of Essential Oils from the Mediterranean Diet on Gut Microbiota and Their Metabolites in Ischemic Heart Disease and Type-2 Diabetes Mellitus

Abstract

Ischemic heart disease (IHD) and type-2 diabetes mellitus (T2DM) remain major health problems worldwide and commonly coexist in individuals. Gut microbial metabolites, such as trimethylamine N-oxide (TMAO) and short-chain fatty acids (SCFAs), have been linked to cardiovascular and metabolic diseases. Previous studies have reported dysbiosis in the gut microbiota of these patients and the prebiotic effects of some components of the Mediterranean diet. Essential oil emulsions of savory (Satureja hortensis), parsley (Petroselinum crispum) and rosemary (Rosmarinus officinalis) were assessed as nutraceuticals and prebiotics in IHD and T2DM. Humanized mice harboring gut microbiota derived from that of patients with IHD and T2DM were supplemented with L-carnitine and orally treated with essential oil emulsions for 40 days. We assessed the effects on gut microbiota composition and abundance, microbial metabolites and plasma markers of cardiovascular disease, inflammation and oxidative stress. Our results showed that essential oil emulsions in mice supplemented with L-carnitine have prebiotic effects on beneficial commensal bacteria, mainly Lactobacillus genus. There was a decrease in plasma TMAO and an increase in fecal SCFAs levels in mice treated with parsley and rosemary essential oils. Thrombomodulin levels were increased in mice treated with savory and parsley essential oils. While mice treated with parsley and rosemary essential oils showed a decrease in plasma cytokines (INFɣ, TNFα, IL-12p70 and IL-22); savory essential oil was associated with increased levels of chemokines (CXCL1, CCL2 and CCL11). Finally, there was a decrease in protein carbonyls and pentosidine according to the essential oil emulsion. These results suggest that changes in the gut microbiota induced by essential oils of parsley, savory and rosemary as prebiotics could differentially regulate cardiovascular and metabolic factors, which highlights the potential of these nutraceuticals for reducing IHD risk in patients affected by T2DM.

Petroselinum crispum (Mill.) Fuss (Parsley): An Updated Review of the Traditional Uses, Phytochemistry, and Pharmacology

“…Due to the role of dysbiosis in the development of cardiovascular disorders, an in vivo study evaluated the effect of supplementation with parsley oil in mice humanized by fecal transplantation from patients with diabetes mellitus and ischemic heart disease. The results showed that parsley oil can modulate gut microbiota and their metabolite trimethylamine N -oxide, along with a reduction in serum inflammatory markers such as interleukins, INFγ, and TNF-α . Aqueous extract of parsley herb has demonstrated antihypertensive effects in a rat model of L-NAME-induced hypertension in both acute (single dose) and chronic (1 week) administration.…”

Nutrition at the Intersection between Gut Microbiota Eubiosis and Effective Management of Type 2 Diabetes

“…Oil seeds cause significant changes in the gut composition profile, such as increased Lactobacillus spp. and SCFA, with reduced production of harmful metabolites such as TMAO [347]. As such, oilseeds and nuts serve as a healthy food source that are intricate components of the Mediterranean diet and modulate important metabolic processes associated with T2DM.…”