On the other hand, predominance of CP in such co-infection is related to plaque rupture. Mycoplasma is the smallest self-replicating microorganism having particular characteristics as cholesterol requirement for growth, drawing the host for immune depression [13] and increase the pathogenicity of co-infective agents [14]. Association of different microorganisms in a host may increase the virulence among them [15, 16] and may explain the disappointing clinical trial results

with anti-chlamydial antibiotic therapy [17, 18]. The objective of the present study was to verify whether inoculation of MP or in association with CP aggravates cholesterol-induced atherosclerosis in apoE KO mice. The severity of atherosclerosis was evaluated by measuring AZD6738 the plaque height, plaque fat area, intima and adventitia Palbociclib research buy inflammation and amount of plaque/surface of the vessel. We also evaluated whether co-infection would cause plaque rupture. Results The experimental infection caused six deaths in the 36 studied male mice: Among the death mice, four were inoculated with MP,

one was inoculated with CP + MP and one was from the sham group. By the end of the experiment, the pooled serum were tested for total cholesterol, HDL and LDL in all groups. The respective values were: 534, 350, 443 and 532; HDL 29, 20, 40, 21 and LDL 435, 215, 316 and 393 mg/dl. After 4 weeks the inoculated mice showed serum antibody titers of: < 1:16 to CP, from 1:8 to 1:16 to MP and the sham did not show antibodies to CP and MP. Electron microscopic of the intimal plaque of a mouse inoculated with MP showed structures suggestive of MP such as irregular rounded bodies with 0.1 to 0.4 μm in diameter, lack of the cell wall, 4-Aminobutyrate aminotransferase containing granular chromatin-like material (Figure 1). One animal of the CP + MP inoculated group exhibited the structures of MP and the elementary bodies of CP in the myocardial fiber characterized by rounded electron-dense bodies enveloped by two membranes (Figure 1A and 1B). Figure 1 Electron microscopic views of Mycoplasma pneumoniae

(MP) and Chlamydia pneumoniae (CP) bodies. Elementary bodies in the myocardial fiber from a mouse of the MP + CP infected group. The close view on the left side shows the double membrane of CP elementary bodies (1A). An intimal plaque from a mouse of the MP infected group, exhibiting two rounded mycoplasma bodies, characterized by only one envelopment membrane (1B). Analysis of the extent and degree of atherosclerosis Table 1 shows the mean and standard deviation of variables in the different groups. P value is the comparison of the infected groups with the sham group, using One Way Analysis of Variance and Dunn’s Methods for non-normally distributed values or Bonferroni’s test for normally distributed values.