3-nitrotyrosine and Cytomegalovirus-Infections

The aim of this study was to assess oxidative stress in pregnant women infected with cytomegalovirus on the basis of 3-nitrotyrosine levels in amniotic fluid (AF). The 3-nitrotyrosine (3-NT) level in AF was measured using the competitive ELISA method. The study groups were as follows: group I consisted of women with IgM and/or IgA; group II were women with only IgG anti-CMV antibodies and group III were seronegative women, used as the control group. Age, gestational age and socioeconomic status were also assessed. The average level of 3-nitrotyrosine in group II and the control group was similar: 53.14 nM 3-NT and 49.78 nM 3-NT, respectively. However, in group I, the lowest level 3-NT in AF was observed - 39.17 nM 3-NT and statistical analysis showed significant differences in levels of 3-NT between group I and the control group (p < 0.01). We conclude that significantly lower levels of 3-nitrotyrosine in pregnant women with CMV infection may indicate an increase in the antioxidant defence mechanisms in these patients.

Topics: Amniotic Fluid; Case-Control Studies; Cytomegalovirus Infections; Female; Humans; Oxidative Stress; Pregnancy; Pregnancy Complications, Infectious; Tyrosine

Although the association between inflammation and atherosclerosis is well established, the biologic events that trigger the local inflammatory response within plaque are not fully understood. Cytotoxic free radicals and infectious agents, both of which are associated with an inflammatory response, have previously been implicated in the initiation and progression of atherosclerosis. In this study, we analyzed carotid plaque for evidence of oxidative vascular injury by determining the presence and distribution of inducible nitric oxide synthase (iNOS) expression and nitrotyrosine formation and for evidence of infection with cytomegalovirus.. Carotid plaque from 51 patients who underwent endarterectomy for either primary (n = 37) or recurrent (n = 14) stenosis were examined histologically (hematoxylin-eosin staining and Masson's trichrome staining) and with immunohistochemistry with specific antibodies to alpha-smooth muscle actin, macrophages (CD68), T-lymphocytes (CD3), and T-cell activation (human leukocyte antigen-DR). Twenty-eight specimens from patients with primary (n = 15) and recurrent (n = 13) stenosis were examined for the presence of iNOS and nitrotyrosine with immunohistochemistry and in situ hybridization (iNOS). Twenty-three additional specimens (22 primary, and 1 recurrent) were analyzed with antibodies to p53, cytomegalovirus, and the polymerase chain reaction (cytomegalovirus, n = 8).. Primary atherosclerotic lesions were either complex heterogenous cellular plaques (n = 29) or relatively acellular fibrous plaques (n = 8). Ten of 14 recurrent plaques were either complex or fibrous lesions, and the remaining four were typical of myointimal thickening. CD68-positive staining cells were detected in all specimens regardless of their structural morphology. CD3-positive cells were interspersed between macrophages in all heterogeneous cellular plaques and only infrequently noted in fibrous plaques. iNOS and nitrotyrosine immunoreactivity were detected in macrophages and smooth muscle cells in all complex and fibrous plaques and in two of four myointimal plaques. The presence of iNOS and nitrotyrosine in plaque correlated with the existence of symptoms in 80% of primary and 62% of recurrent lesions. Cytomegalovirus was detected in only two of 23 carotid specimens (9%).. The association between ischemic cerebrovascular symptoms and iNOS and nitrotyrosine immunoreactivity in complex primary and recurrent carotid plaque and the infrequent occurrence of cytomegalovirus in primary carotid lesions suggests that ongoing free radical oxidative damage rather than viral infection may contribute to plaque instability in patients with complex and fibrous carotid plaques.

Topics: Aged; Carotid Arteries; Carotid Stenosis; Cytomegalovirus Infections; Female; Humans; Immunohistochemistry; In Situ Hybridization; Intracranial Arteriosclerosis; Male; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Polymerase Chain Reaction; Recurrence; Risk Factors; Tyrosine