Avaliação do efeito imunomodulador da β-lapachona em modelo de sepse e in vitro

Abstract

Sepsis is a systemic inflammatory response resulting from an infection and failure of the host immune response. Despite the current treatments, sepsis remains one of the main causes of death in ICU. Thus, it is necessary to discover new therapies developed to control the infection. Β-lapachone is an ortho-naphthoquinone obtained from the bark of Tabebuia avellanedae known for its antimicrobial and anti-inflammatory activity through immunomodulation. In this study, the effect of β-lapachone on polymicrobial infection induced by ligature and cecal perforation (CLP) was evaluated. Swiss mice were divided into 4 pre and post treated groups, and one of them only received the surgical procedure without induction of CLP (Sham). The others received intraperitoneal saline 0.9%, antibiotic (Ceftriaxone or ertapenem) and β-lapachone 24 hours before, induction time (Pretreatment) of CLP and 7 days after CLP (Post treatment). The survival rate was analyzed for a period of 16 days. After 12, 24 hours and 7 days of the surgical procedure the samples of the animals of each group were collected and evaluated the leukocyte migration, bacterial load, oxidative parameters (NO, MDA and TEAC) and phagocytosis. In addition, the cell viability of the compound in different concentrations was investigated in vitro. The group pretreated with β lapachone showed an increase in the survival rate of 100% in 16 days. Treatment with β-lapachone caused an increase in the migration of mononuclear cells and reduced the number of neutrophils to the peritoneum. It also showed reduced bacterial load, reduced NO and MDA levels and increased serum antioxidant levels. On the other hand, there was an increase in the concentrations of MDA in samples of animal organs despite the increase of total antioxidants. With regard to posttreatment, there was an increase in survival of 60% and some parameters similar to the CLP group treated with saline. In the cell viability assay it was found that the concentration of 1.00 μM maintained 82% viable. Thus, the best results of the potential pharmacological effect of the compound on pretreatment may have occurred because the therapeutic intervention occurs earlier in the disease process compared to the clinical situation.