Avaliação do mecanismo de ação da milonina no modelo murino de lesão pulmonar aguda e estudos in silico

Abstract

Acute lung injury (ALI) is a pathology of inflammatory origin with neutrophil infiltration, damage to the alveolar-capillary barrier, production of cytokines leading to acute respiratory failure. The complexity of physiological/immunological events makes it difficult to develop an effective pharmacotherapy. Thus, therapeutic strategies that promote the resolution of inflammation have been developed, using natural products as sources of new anti-inflammatory molecules. In this context, the aim of this study was to evaluate the anti-inflammatory potential and mechanism of action of milonine, a morphine alkaloid from Cissampelos sympodialis Eichl (Menispermaceae) in the murine model of ALI. For this, BALB/c mice were challenged with lipopolysaccharide (LPS) and treated with milonine (2.0 mg/kg). Twenty-four hours after the challenge, the animals were euthanized, and bronchoalveolar lavage (BAL), blood and lungs were collected for cellular and molecular analysis. For the prediction of molecular targets and pharmacokinetic and pharmacodynamic profiles, in silico studies were performed using ADMET and Osiris software. Treatment with milonine inhibited the migration of inflammatory cells to the lung, mainly neutrophils, reduced protein exudate, pulmonary edema, and cytokines, IL-1β, IL-6 and TNF-α in BAL, only IL-6 was reduced to a systemic level. The histological changes were attenuated with the treatment with milonine, with a reduction in leukocytes and maintenance of bronchial alveolar architecture, confirmed by morphometric data. The anti-inflammatory effect of milonine is associated with the inhibition of kinase B (or Akt) and nuclear factor κB (NFκB). In silico molecular docking studies showed that the alkaloid had a binding energy of -43.96 kcal/mol and formed hydrophobic interactions with the amino acids Ile124 and Phe126 at the MD-2 receptor associated with the Toll Like-4 receptor. The alkaloid showed a promising ADMET profile (absorption, distribution, metabolism, excretion and toxicity) related to safety parameters and good availability. Therefore, milonine showed an immunomodulatory effect on the inflammatory process of acute lung injury associated with regulatory factors of inflammatory cytokine genes, and with good safety and bioavailability, placing it as a potential molecule for the treatment of lung inflammation.