Marcadores de estresse oxidativo no contexto do aborto espontâneo associado a infecção por Ureaplasma parvum

Abstract

Abortion is the interruption of pregnancy before the 22nd gestational week or when the fetus weighs less than 500g. It can occur naturally or be induced and has multiple causes, including genital infections. Genital tract infections can ascend to the uterine cavity and account for 15% of early abortions and 66% of late abortions. Exacerbated inflammatory responses resulting from the infectious process affect gestational homeostasis, contributing to a pro-inflammatory profile and altering the oxidative state. The main objective of this study was to evaluate markers of oxidative stress in the context of spontaneous abortion associated with Ureaplasma parvum infection. Biological samples of placental tissue were collected from women who experienced spontaneous abortion and women who had full-term deliveries. When evaluating markers of lipid peroxidation and protein carbonylation, elevated levels of TBARS and protein carbonylation were identified in abortion cases, along with increased CAT antioxidant activity and reduced GPx activity, while SOD activity remained unchanged. However, the profile of lipid

peroxidation was accentuated in UP-infected abortions. GPx levels were reduced in UP- infected abortions compared to infected controls, while SOD and CAT showed no

differences. The SOD/CAT ratio was reduced, and the SOD/GPx ratio was elevated in the UP groups compared to those without infection. Regarding gene expression, infected abortions showed reduced Mn SOD/GPx and decreased CuZn SOD/GPx and Mn SOD/GPx expression in both abortion and infected control groups compared to those without infection. Additionally, nitrite levels increased in UP-infected abortions. This study demonstrated that UP infection may contribute to altering the oxidant profile, suggesting that an imbalance in oxidative stress could play a role in spontaneous abortion associated with bacterial infection.