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Bisphenol A (BPA) is an environmental endocrine disrupter. Excess exposure to BPA may increase susceptibility to many metabolic disorders, but it is unclear whether BPA exposure has any adverse effects on the development of atherosclerosis. To determine whether there are such effects, we investigated the response of Watanabe heritable hyperlipidemic (WHHL) rabbits to 400-µg/kg BPA per day, administered orally by gavage, over the course of 12 weeks and compared aortic and coronary atherosclerosis in these rabbits to the vehicle group using histological and morphometric methods. In addition, serum BPA, cytokines levels and plasma lipids as well as pathologic changes in liver, adipose and heart were analyzed. Moreover, we treated human umbilical cord vein endothelial cells (HUVECs) and rabbit aortic smooth muscle cells (SMCs) with different doses of BPA to investigate the underlying molecular mechanisms involved in BPA action(s). BPA treatment did not change the plasma lipids and body weights of the WHHL rabbits; however, the gross atherosclerotic lesion area in the aortic arch was increased by 57% compared to the vehicle group. Histological and immunohistochemical analyses revealed marked increases in advanced lesions (37%) accompanied by smooth muscle cells (60%) but no significant changes in the numbers of macrophages. With regard to coronary atherosclerosis, incidents of coronary stenosis increased by 11% and smooth muscle cells increased by 73% compared to the vehicle group. Furthermore, BPA-treated WHHL rabbits showed increased adipose accumulation and hepatic and myocardial injuries accompanied by up-regulation of endoplasmic reticulum (ER) stress and inflammatory and lipid metabolism markers in livers. Treatment with BPA also induced the expression of ER stress and inflammation related genes in cultured HUVECs. These results demonstrate for the first time that BPA exposure may increase susceptibility to atherosclerosis in WHHL rabbits.

Background14,15-Epoxyeicosatrienoic acids (14,15-EETs) generated from arachidonic acid by cytochrome P450 epoxygenases have beneficial effects in certain cardiovascular diseases, and increased 14,15-EET levels protect the cardiovascular system. 14,15-EETs are rapidly hydrolyzed by soluble epoxide hydrolase (sEH) to the corresponding 14,15-dihydroxyeicosatrienoic acids (14,15-DHETs), which are generally less biologically active but more stable metabolite. A functionally relevant polymorphism of the CYP2J2 gene is independently associated with an increased risk of coronary heart disease (CHD), and the major CYP2J2 product is 14,15-EETs. 14,15-DHETs can be considered a relevant marker of CYP2J2 activity. Therefore, the aim of the present study was to evaluate the plasma 14,15-DHET levels to reflect the 14,15-EET levels in an indirectly way in patients with CHD, and to highlight the growing body of evidence that 14,15-EETs also play a role in anti-inflammatory and lipid-regulating effects in patients with CHD. This was achieved by investigating the relationship between 14,15-DHETs and high-sensitivity C-reactive protein (hs-CRP) and blood lipoproteins.MethodsSamples of peripheral venous blood were drawn from 60 patients with CHD and 60 healthy controls. A 14,15-DHET enzyme-linked immunosorbent assay kit (14,15-DHET ELISA kit) was used to measure the plasma 14,15-DHET levels. Hs-CRP, total cholesterol, triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein-cholesterol levels were measured.Results14,15-DHET levels (2.53 ± 1.60 ng/mL) were significantly higher in patients with CHD as compared with those of the healthy controls (1.65 ± 1.54 ng/mL, P < 0.05). There was a significant positive correlation between 14,15-DHETs and hs-CRP levels (R = 0.286, P = 0.027). However, there was no significant correlation between 14,15-DHETs and blood lipoproteins (all, P > 0.05).ConclusionsIncreased plasma 14,15-DHET levels reflect the decreased of 14,15-EET levels in an indirectly way. Indicated that decreased plasma 14,15-EET levels might be involved in the inflammatory reaction process in atherosclerosis.

IRAK1 and miR-499 play an important role in the etiology of rheumatoid arthritis. Few studies to date have focused on the influence of the IRAK1 rs3027898 C/A and hsa-mir-499 rs3746444 T/C polymorphisms in the susceptibility of the Chinese population to rheumatoid arthritis. We hypothesized that these polymorphisms may contribute to rheumatoid arthritis susceptibility. We studied IRAK1 rs3027898 C/A and hsa-mir-499 rs3746444 T/C gene polymorphisms in 214 rheumatoid arthritis cases and 478 controls in a Chinese population. Genotyping was performed by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). When the IRAK1 rs3027898 CC homozygote genotype was used as the reference group, the AA genotype was associated with significantly increased risk of rheumatoid arthritis (odds ratio (OR) = 1.91, 95 % confidence interval (CI) = 1.12-3.26, p = 0.017). A significantly increased risk of RA associated with the IRAK1 rs3027898 AA genotype was more evident among females, younger patients, CRP negative patients and both anti-CCP positive and negative patients compared with the IRAK1 rs3027898 CC/CA genotypes. The hsa-mir-499 rs3746444 T/C single nucleotide polymorphism (SNP) was not significantly associated with the risk for rheumatoid arthritis. Our findings suggest that the functional SNP IRAK1 rs3027898 C/A variant allele is associated with the development of rheumatoid arthritis. However, the hsa-mir-499 rs3746444 T/C polymorphism may not be associated with susceptibility to rheumatoid arthritis.