Infection and Microparticles may Cause Complication of Atherosclerotic Plaques

Abstract

Atherosclerosis is frequently associated with diabetes, obesity, metabolic syndrome and oxidized low density lipoproteins (oxLDL). Many studies have reported association of infection with such disorders, but with controversial results. In our view, these findings have relationship with technical differences. We showed previously, presence of infectious agents inside of ruptured plaque, using immunohistochemistry and electron microscopy. More recently, we detected Electron Lucent microparticles (ELMP) and Mycoplasma pneumoniae (Mp) lipoproteins in vulnerable plaques (VP).However, we have interest to know if ELMPs contain Mp lipoprotein antigens and if they are related to oxLDL and plaque vulnerability. Methods:We studied three groups of coronary arteries: VP (vulnerable plaque; n=13), stable plaques (SP; n=7), and normal arteries (NA; n=7). All cases were studied by immuno electron microscopy, and the mean numbers of ELMPs, oxLDL and Mp antigens, inside and outside ELMP, were obtained. Double colloidal immunogold particles (anti-oxLDL and anti-Mp) allowed the simultaneous localization of both antigens.Results: There was a significant higher amount of ELMPs in VP, with positive dots for both oxLDL and Mp antigens inside them, compared to other two groups (p<0.01). Mp and oxLDL antigens were co-localized in lipidic nanoparticles intra ELMPs, showing positive correlation (r=0.60; P=0.04). High amount of oxLDL and Mp antigens extra ELMPs were seen in VP, but not in stable plaques. Conclusion:Plaque vulnerability in atherosclerosis may be related to presence of ELMPs, containing M. pneumoniae lipoproteins and oxLDL. We hypothesized that M. pneumoniae lipoproteins oxidation could be a mechanism for this association. However, further data are necessary to prove this hypothesis.

Commentary: Comparison of the Protective Effects of Individual Components of Particulated trans-Sialidase (PTCTS), PTC and TS, against High Cholesterol Diet-Induced Atherosclerosis in Rabbits

“…We found greater number of such microvesicles, which had greater quantity of oxLDL and collagenases, on unstable plaque than on normal artery or on stable plaque (19).…”

Morphomolecular Characterization of Serum Nanovesicles From Microbiomes Differentiates Stable and Infarcted Atherosclerotic Patients

“…An atherosclerotic plaque containing proinflammatory cytokines, reactive oxygen species, high levels of oxidized low-density lipoproteins (oxLDL), cholesterol crystals and damage-associated molecular patterns (8), due to damaged proteins, lipids and DNA (9), is a microenvironment at risk for plaque rupture and thrombosis (10), and might be explained by the presence of a pathogenic microbial community (11). In previous work by our group, the presence of archaea was related to the aggravation of atherosclerosis (12,13) and with heart failure in Chagas disease, where archaeal DNA was detected in nanoparticles in the serum (14).…”

Comparison of the Protective Effects of Individual Components of Particulatedtrans-Sialidase (PTCTS), PTC and TS, against High Cholesterol Diet-Induced Atherosclerosis in Rabbits

“…When exposed to stress conditions, Mycoplasmas can release microparticles (MPs) containing proteins and genetic material from the originating cells as a response to such stress, thus allowing their adaptation to various environments [ 5 , 6 ].…”