Effect of (-)-α-Bisabolol on the Inflammatory Response in Systemic Infection Experimental Model in C57BL/6 Mice.

(-)-α-Bisabolol (BISA) is an unsaturated monocyclic sesquiterpenes compound, mainly found in the essential oil of chamomile (Matricaria chamomilla). It has been reported that this compound has several biological activities, but there are few studies evaluating the activity of this compound in the systemic inflammatory response in infectious processes. The aim of this study was to evaluate the effect of BISA on the inflammatory response and survival rate in a systemic infection model, and in vitro neutrophils phagocytic activity. BISA at concentration of 3, 10, 30, and 90 µg/ml did not presented in vitro cytotoxicity in MTT assay, and at concentrations of 1 and 3 µg/ml the BISA treatment increased in vitro phagocytic neutrophil activity. For the inflammatory response study, we verified the BISA treatment effect in a cecal ligation and puncture (CLP)-induced systemic infection model in mice; in this model, we demonstrate that BISA at dose of 100 mg/kg reduced the leukocyte recruitment in peritoneal cavity; at dose of 200 mg/kg, the NO concentration was increased in the peritoneal cavity. The bacteria CFU number was reduced in mice blood in the BISA treatment, at doses of 100 and 200 mg/kg. The BISA treatment at doses of 50 and 100 mg/kg increased the myeloperoxidase activity and reduction NO production in lung tissue of mice in CLP model. At dose of 100 mg/kg, the BISA treatment was able to reduce the mortality rate of mice submitted to CLP-induced sepsis and observed for 7 days. The results suggest an effect of BISA on inflammatory response, with activity on leukocyte chemotactic and NO production, in addition to increasing the survival rate of animals submitted to CLP model.

Effect of Lavender (Lavandula angustifolia) Essential Oil on Acute Inflammatory Response.

Lavandula angustifolia is a plant of Lamiaceae family, with many therapeutic properties and biological activities, such as anticonvulsant, anxiolytic, antioxidant, anti-inflammatory, and antimicrobial activities. The aim of this study was to evaluate the effect of Lavandula angustifolia Mill. essential oil (LEO) on acute inflammatory response. LEO was analyzed using gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR) methods and showed predominance of 1,8-cineole (39.83%), borneol (22.63%), and camphor (22.12%). LEO at concentrations of 0.5, 1, 3, and 10 µg/ml did not present in vitro cytotoxicity. Additionally, LEO did not stimulate the leukocyte chemotaxis in vitro. The LEO topical application at concentrations of 0.25, 0.5, and 1 mg/ear reduced edema formation, myeloperoxidase (MPO) activity, and nitric oxide (NO) production in croton oil-induced ear edema model. In carrageenan-induced paw edema model, LEO treatment at doses of 75, 100, and 250 mg/kg reduced edema formation, MPO activity, and NO production. In dextran-induced paw edema model, LEO at doses of 75 and 100 mg/kg reduced paw edema and MPO activity. In conclusion, LEO presented anti-inflammatory activity, and the mechanism proposed of LEO seems to be, at least in part, involving the participation of prostanoids, NO, proinflammatory cytokines, and histamine.

Protective Effect of Cymbopogon citratus Essential Oil in Experimental Model of Acetaminophen-Induced Liver Injury.

To investigate the hepatoprotective effect of Cymbopogon citratus or lemongrass essential oil (LGO), it was used in an animal model of acute liver injury induced by acetaminophen (APAP). Swiss mice were pretreated with LGO (125, 250 and 500[Formula: see text]mg/kg) and SLM (standard drug, 200[Formula: see text]mg/kg) for a duration of seven days, followed by the induction of hepatotoxicity of APAP (single dose, 250[Formula: see text]mg/kg). The liver function markers alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase were determined to evaluate the hepatoprotective effects of the LGO. The livers were used to determine myeloperoxidase (MPO) activity, nitric oxide (NO) production and histological analysis. The effect of LGO on leukocyte migration was evaluated in vitro. Anti-oxidant activity was performed by assessing the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) in vitro. LGO pretreatment decreased significantly the levels of ALT, AST and ALP compared with APAP group. MPO activity and NO production were decreased. The histopathological analysis showed an improved of hepatic lesions in mice after LGO pretreatment. LGO inhibited neutrophil migration and exhibited anti-oxidant activity. Our results suggest that LGO has protective activity against liver toxicity induced by paracetamol.

Effect of patchouli (Pogostemon cablin) essential oil on in vitro and in vivo leukocytes behavior in acute inflammatory response.

PURPOSE: The aim of this study was to evaluate the effect of Pogostemon cablin essential oil (PEO) on leukocyte behavior in the inflammatory response. METHODS AND RESULTS: PEO was analyzed using Gas Chromatography/Mass Spectrometry (GC/SM) and Nuclear Magnetic Resonance Spectroscopy (NMR) methods and showed predominance of patchoulol (38.50%), α-bulnesene (20.37%), α-guaiene (12.31%), seychellene (8.33%) and α-patchoulene (4.91%). PEO at concentrations of 1, 3, 10, 30, 60 and 90µg/ml reduced the in vitro neutrophil chemotaxis toward fMLP, and at concentrations of 3 and 10µg/ml, increased the phagocytic activity of neutrophils. Topical application of PEO in high concentrations promoted an increase of ear edema and myeloperoxidase (MPO) activity. However, the oral treatment with 100, 200 and 300mg/kg reduced leukocyte recruitment, nitric oxide (NO) production, and rolling and adherent leukocyte number in the microcirculation. CONCLUSION: PEO affects the leukocyte behavior, and the mechanism proposed of PEO seems to be, at least in part, involving the participation of NO and pro-inflammatory cytokines.