Context:Syzygium aromaticum (L.) Merr. & Perry (Myrtaceae), commonly known as clove, originally found in the Muluku Islands in East Indonesia, is widely used as a spice and has numerous medicinal properties.Objective: This study investigated the antioxidant potential of S. aromaticum aqueous extract (SAAE) in vitro and its protective effects on lipopolysaccharide (LPS)-induced lung inflammation in mice.Material and methods: Neutrophils were isolated from healthy donors and reactive oxygen species (ROS) generation was measured by luminol-amplified chemiluminescence. Superoxide anion generation was detected by cytochrome c reduction assay. H2O2 was detected by DCFH fluorescence assay. Myeloperoxidase (MPO) activity was mesured by tetramethyl benzidine oxidation method. To study the anti-inflammatory activity of SAAE, lung inflammation was induced in mice (BALB/c) by intra-tracheal instillation of lypopolysaccharide (5 µg/mouse), and SAAE (200 mg/kg body weight) was injected intraperitoneally prior to LPS administration. Bronchoalveolar lavage and lung tissue were collected to assess inflammatory cells count and total protein content. Metalloproteinases activity was detected by zymography technique.Results: SAAE inhibited luminol-amplified chemiluminescence of resting neutrophils and N-formyl-methionyl-leucyl-phenylalanine- or phorbol myristate acetate-stimulated neutrophils, with an inhibitory effect starting at a concentration as low as 0.5 µg/mL. Moreover, SAAE reduced significantly MPO activity and it exhibits a dose-dependent action (IC50 = 0.5 µg/mL). In vivo results showed that SAAE decreased markedly neutrophil count (From 61% to 15%) and proteins leakage into bronchoalveolar lavage fluid. Gelatin zymography assay showed that S. aromaticum inhibited MMP-2 (15%) and MMP-9 (18%) activity in lung homogenates.Discussion and conclusion: Our results suggest that the anti-inflammatory activity of SAAE, in vivo, is due to the inhibition of ROS production and metalloproteinases activity via its action on MPO. According to these findings, SAAE could be a potential source of new compounds with anti-inflammatory activity.

Aim: Plants used in traditional medicine produce diverse active metabolites exhibiting various medicinal properties. For several centuries Citrillus colocynthis and Punica granatum have been used to treat inflammation, cancer, edema, bacterial infections and diabetes. The objectives of this work were to study the effect of C. colocynthis and P. granatum peel aqueous extracts, on activity of metalloproteinases, enzymes implicated in chronic inflammatory diseases such Chronic Obstructive Pulmonary Disease (COPD) and emphysema. Materials and Methods: Lung inflammation was induced in the mice (Strain BALB/c) by intra-tracheal instillation of lipopolysaccharide (5 µg/mouse) and P. granatum peel extract (PGE) or C. colocynthis peel extract (CCPAE) (200 mg/Kg body weight) was injected intraperitoneally prior to LPS administration. Bronchoalveolar lavage and lung tissue were collected to assess inflammatory cells count and total protein content. Metalloproteinases activity and expression was detected by RT-PCT and zymography techniques, respectively. Results: Results showed that PGE and CCPE decreased markedly neutrophils count and proteins leakage into Bronchoalveolar Lavage Fluid (BALF). Gelatin zymography assay showed that PGE inhibited MMP-2 and MMP-9 activity in BALF and in lung homogenates. However, CCPE inhibited MMP-2 and MMP-9 in lung homogenates but only MMP-2 in BALF. Furthermore, both PGE and CCPAE inhibit MMP-2 and-9, expression in the lung. Conclusion: Our results showed that PGE and CCPAE exhibit anti-inflammatory and, antimetalloproteinases especially MMP-2 and-9, activities. According to these findings, these natural products could be used as a potential source of new compounds with anti-inflammatory and anti-metalloproteinases activity.

We investigated the effect of Punica granatum peel aqueous extract (PGE), on pulmonary inflammation and alveolar degradation induced by intratracheal administration of Elastase in Sprague Dawley rats. Lung inflammation was induced in rats by intratracheal instillation of Elastase. On day 1 and 2, animals received an intraperitoneal injection of PGE (200 mg/mL), three hours later, they were intratracheally instilled with 25U/kg pancreatic porcine Elastase. Animals were sacrificed 7 days later. Bronchoalveolar lavage (BAL) were collected and cellularity, histology and mRNA expression of Monocyte chemotactic protein 1(MCP-1), Tumor Necrosis Factor-Alpha (TNF-α), Interleukin 6 (IL-6), and Matrix Metalloproteinase-2 (MMP-2) were studied. In addition, activity of TNF-α, IL-6 and MCP-1 on BAL were also analyzed by ELISA Kit. Elastase administration increased: BAL cellularity, neutrophils recruitment and BAL MCP-1, IL-6 expressions. It also increased lung TNF-α, MCP-1, MMP-2 expressions, platelets recruitment, histological parameters at 7 th day of elastase treatment. Intraperitoneal injection of 200 mg/kg of PGE reduced, significantly, BAL cellularity, and neutrophils recruitment. However, in animal treated with PGE, MCP-1, MMP-2 and IL-6 on day 7, were similar to the Sham group. Treatment with PGE (200 mg/ kg) also significantly reduced lung TNF-α, and MCP-1 expression. This study reveals that PGE Punica granatum protects against elastase lung inflammation and alveolar degradation induced in rats.

Citrillus colocynthis peel aqueous extract (CCPAE) is widely used to treat disorders such as inflammation, ulcers and infections, but its pharmacological target is not known. The objectives of this work were to study the effect of C. colocynthis peel aqueous extract, on human neutrophil reactive oxygen species (ROS) production in vitro, and to evaluate its protective effect on lipopolysaccharide (LPS)-induced lung inflammation in vivo in mice. Neutrophils were isolated from blood of healthy volunteers. ROS generation was measured by luminol-amplified chemiluminescence. Superoxide anion generation was detected by the cytochrome c reduction assay. H 2 O 2 was detected by horseradish peroxidase (HRP)-amplified chemiluminescence assay. Myeloperoxidase (MPO) activity was measured by the tetramethylbenzidine oxidation method. Lung inflammation was induced in mice by LPS instillation. CCPAE inhibited luminol-amplified chemiluminescence of resting neutrophils and N-formylmethionyl-leucyl-phenylalanine (fMLF)-or phorbolmyristate acetate (PMA)-stimulated neutrophils, in a concentration-dependent manner. CCPAE also inhibited superoxide anion generation; and did not scavenge H 2 O 2 and superoxide anions nor inhibited MPO activity in vitro suggesting that it inhibits nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation. In vivo studies showed that CCPAE attenuated LPS-induced lung inflammation in mice. This study shows that CCPAE inhibits neutrophil ROS production and attenuates LPS-induced lung inflammation in mice. Inhibition of NADPH oxidase activation by CCPAE could explain its anti-inflammatory action.