RESUMO O objetivo deste trabalho é determinar os níveis de HMGB1, TNF-alfa e IL-8 no lavado broncoalveolar (BAL), bem como quantificar a expressão sérica de TLR2 e TLR4 mRNA em tecido pulmonar de coelhos com dois graus de lesão pulmonar aguda (LPA). Os animais foram distribuídos aleatoriamente em grupos com LPA grave (S) e leve / moderada (MM), induzidas com solução salina morna, e um grupo controle. HMGB1, TNF-alfa, IL-8, TLR2mRNA e TLR4mRNA foram medidos após a indução de LPA e quatro horas de ventilação mecânica. Os resultados mostraram níveis aumentados de IL-8, TNF-alfa, HMGB1 e TLR4mRNA nos grupos com LPA. As concentrações de HMGB1, IL-8 e TNF-alfa no LBA foram maiores no S comparado ao MM. Aumento de TLR4mRNA foi observado em S e MM versus controle. Os resultados sugerem uma participação precoce da HMGB1 na LPA em conjunto com IL-8 e TNF-alfa e associação com a gravidade da LPA. O TLR4 foi expresso na ALI e possivelmente possui papel precoce na fisiopatologia da LPA, mas sem associação com a gravidade.

ABSTRACT The aim of this work was to measure HMGB1, TNF-alpha, and IL-8 in bronchoalveolar lavage (BAL), serum and TLR2 and TLR4mRNA expression in lung tissue of rabbits with two grades of acute lung injury (ALI). The animals were randomly assigned to groups with severe (S) and mild/moderate (MM) ALI, induced with warm saline, and a control group. HMGB1, TNF-alpha, IL-8, TLR2mRNA and TLR4mRNA were measured after ALI induction. The results showed increased levels of IL-8, TNF-alpha, HMGB1 and TLR4mRNA in the ALI groups. HMGB1, IL-8 and TNF-alpha concentrations in BAL were higher in S compared MM. Increased TLR4mRNA was observed in S and MM versus control. The results suggest an early participation of HMGB1 in ALI together with IL-8 and TNF-alpha and association with severity. TLR4 has early expression and role in ALI pathophysiology but is not associated with severity.

Although oxidative stress and inflammation are important mechanisms in the pathophysiology of preeclampsia and preterm diseases, their contribution to the respiratory prognosis of premature infants of hypertensive mothers is not known. Our objective was to determine the levels of oxidative stress and inflammation markers in the airways of premature infants born to hypertensive and normotensive mothers, in the first 72 h of life, and to investigate whether they are predictors of bronchopulmonary dysplasia (BPD)/death. This was a prospective study with premature infants less than 34 weeks’ gestation on respiratory support who were stratified into 2 groups: 32 premature infants of hypertensive mothers and 41 of normotensive women, with a mean gestational age of 29 weeks. Exclusion criteria were as follows: diabetes mellitus, chorioamnionitis, malformation, congenital infection, and death within 24 h after birth. The outcome of interest was BPD/death. Malondialdehyde (MDA), nitric oxide (NO), and interleukin 8 (IL-8) were measured in airway aspirates from the first and third days of life and did not differ between the groups. Univariate and multivariate statistical analyses were performed. The concentrations of MDA, NO, and IL-8 were not predictors of BPD/death. Premature infants who developed BPD/death had higher levels of IL-8 in the first days of life. The gestational age, mechanical ventilation, and a small size for gestational age were risk factors for BPD/death. In conclusion, the biomarkers evaluated were not increased in premature infants of hypertensive mothers and were not predictors of BPD/death.