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Eugenia brejoensis Mazine (Myrtaceae) is source of an essential oil (EbEO) with anti-infective activities against Staphylococcus aureus. This study evaluated the antimicrobial and anti-inflammatory potentials of EbEO in S. aureus-infected skin wounds. The excisional lesions (64 mm2) were induced on Swiss mice back (6 to 8-week-old) that were allocated into 3 groups (n = 12): 1) non-infected wounds (CON); 2) wounds infected with S. aureus ATCC 6538 (Sa); 3) S. aureus-infected wounds and treated with EbEO (Sa + EbEO). The infected groups received approximately 104 CFU/wound. The animals were treated with EbEO (10 µg/wound/day) or vehicle from the 1-day post-infection (dpi) until the 10th dpi. The clinical parameters (wound area, presence of exudate, edema intensity, etc.) were daily analyzed. The levels of inflammatory mediators (cytokines, nitric oxide, VEGF) and bacterial load were measured at the cutaneous tissue at 4th dpi and 10th dpi. Topical application of EbEO accelerated wound contraction with an average contraction of 83.48 ± 11.27 % of the lesion area until 6th dpi. In this period, the rates of lesion contraction were 54.28 ± 5.57% and 34.5 ± 2.67% for CON and Sa groups, respectively. The positive effects of EbEO on wound contraction were associated with significantly (p < 0.05) reduction on bacterial load and the release of inflammatory mediators (IL-6, IL-17A, TNF-α, NO and VEGF). Taken together, these data confirm the antimicrobial potential of EbEO and provide insights into its anti-inflammatory effects, making this essential oil an interesting candidate for the development of new therapeutic alternatives for infected cutaneous wounds.

Abstract: Cinnamaldehyde (CNM) is a cyclic terpene alcohol found as the major compound of essential oils from some plants of the genus Cinnamomum (Lauraceae). CNM has several reported pharmacological activities, including antimicrobial, antivirulence, antioxidant, and immunomodulatory effects. These properties make CNM an attractive lead molecule for the development of anti-infective agents. In this descriptive review, we discuss the application of CNM in experimental models of microbial infection using invertebrate and vertebrate organisms. CNM (pure or in formulations) has been successfully applied in the treatment of infections caused by a range of bacterial (such as Cronobacter sakazakii, Escherichia coli, Listeria monocytogenes, Mycobacterium tuberculosis, Pseudomonas aeruginosa, Salmonella enterica, Staphylococcus aureus, Streptococcus agalactiae, Vibrio cholerae) and fungal (such as Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans) pathogens. All these experimental evidence-based findings have promoted the use of cinnamaldehyde as the leading molecule for developing new anti- infective drugs.

Context: Buchenavia tetraphylla (Aubl.) RA Howard (Combretaceae: Combretoideae) is an ethnomedicinal plant with reported antifungal action. Objective: This study evaluates the antimicrobial activity of B. tetraphylla leaf extracts against clinical isolates of Candida albicans. The morphological alterations, combinatory effects with fluconazole and the cytotoxicity of the active extract were analyzed. Materials and methods: Extracts were obtained using different solvents (hexane: BTHE; chloroform: BTCE; ethyl acetate: BTEE; and methanol: BTME). Antimicrobial activity was determined by the broth microdilution method using nine strains of C. albicans isolated from vaginal secretions and one standard strain (UFPEDA 1007). Results: All extracts showed anti-C. albicans activity, including against the azole-resistant strains. The MIC values ranged from 156 to 2500 μg/mL for the BTHE; 156 to 1250 μg/mL for the BTCE; 625 to 1250 μg/mL for the BTME and 625 μg/mL to 2500 μg/mL for the BTEE. BTME showed the best anti-C. albicans activity. This extract demonstrated additive/synergistic interactions with fluconazole. Scanning electron microscopy analysis suggested that the BTME interferes with the cell division and development of C. albicans. BTME showed IC50 values of 981 and 3935 μg/mL, against J774 macrophages and human erythrocytes, respectively. This extract also enhanced the production of nitric oxide by J774 macrophages. Discussion and conclusion: Buchenavia tetraphylla methanolic extract (BTME) is a great source of antimicrobial compounds that are able to enhance the action of fluconazole against different C. albicans strains; this action seems related to inhibition of cell division.

Objective: To review the antidepressant activity and mechanisms of action of plants that have antidepressant action. Literature Review: The use of plants for medicinal purposes has been used as an adjunct to the treatment of depression due to easy access by the population, few side effects and lower cost. Based on the studies, the plants St. John's wort, ground turmeric, anona and lavender have antidepressant potential for acting in different ways in depression, either by inhibiting the reuptake of serotonin or by modulation in the dopaminergic and serotonergic pathways. Final Considerations: From the studies of the mechanisms of action it was found that the plants studied can modulate the brain signaling pathways responsible for the patient's mood, with the reuptake of serotonin (inhibition of the serotonin transporter protein) the main mechanism of action shared between them. In addition, some of these plants can modulate not only the concentrations of serotonin in the synaptic cleft, but also dopamine. It is worth mentioning that, although these actions have been scientifically proven, much research is still needed to ensure the safe use of these agents as herbal medicines in the alternative or adjunctive treatment of depressive disorders.

Objective: To describe the importance of medicinal plants in the social and pharmacological context, demonstrating the anti-inflammatory therapeutic potential and the mechanism of action of drugs present in the chemical composition of four plants present in the Brazilian flora. Methods: A bibliographic survey on the topic was carried out, using the descriptors: Activity, Anti-inflammatory, Plants, Flora, Brazilian. In Scielo, Google Scholar and PUBMED databases. For the inclusion of works, the following criteria were used: Articles from research relevant to the topic (regardless of date) and relevant publications from the year 2007. Results: The inflammatory process is a target for the treatment of various diseases and development new treatments are needed. We discuss here the anti-inflammatory potential and the mechanism of action of the following plants: Uncaria tomentosa, Schinus terebinthifolius Raddi and Mentha piperita demonstrated through in vitro studies and murine models of diseases. The species showed anti-inflammatory action by reducing the production of inflammatory mediators and inhibiting the activity of important pro-inflammatory enzymes, such as phospholipase A2 and cycloxygenase. Final considerations: The four plant species covered in this article had significant anti-inflammatory effects, therefore, they can be suggested as a source of potential new drugs.

Rheumatoid arthritis (RA) is characterized by inflammation of one or more joints, and affects ~1% of the adult population worldwide. Sulforaphane (SFN) is a natural compound that has been suggested as an antioxidant. Here, SFN’s effects were evaluated in a murine mono-arthritis model. Mono-arthritis was induced in mice by a single intra-articular injection of Complete Freund’s Adjuvant (CFA-10 µg/joint, in 10 µL) into the ipsilateral joint. The contralateral joint received an equal volume of PBS. On the 4th day post-joint inflammation induction, animals received either SFN (10 mg/kg) or vehicle (3% DMSO in saline), intraperitoneally (i.p.), twice a day for 3 days. Joint swelling and secondary mechanical allodynia and hyperalgesia were evaluated over 7 days post-CFA. After this period, animals were culled and their blood and synovial fluid samples were collected for analysis of cell populations, cytokine release and thioredoxin reductase (TrxR) activity. Knee joint samples were also collected for histology. SFN reduced joint swelling and damage whilst increasing the recruitment of Ly6C+ and Ly6G+ cells to CFA-injected joints. SFN-treated animals presented down-regulation of CD11b and CD62L on synovial fluid Ly6G+ cells. Synovial fluid samples obtained from CFA-injected joints and plasma samples of SFN-treated mice presented higher levels of IL-6 and increased activity of TrxR, in comparison with controls. These results indicate that SFN reduces knee joint damage by modulating cell activation/migration to the joints, cytokine production and increasing the activity of TrxR, and therefore, may represent an alternative treatment to joint inflammation.

Severe wounds result in large lesions and/or loss of function of the affected areas. The treatment of wounds has challenged health professionals due to its complexity, especially in patients with chronic diseases (such as diabetes), and the presence of pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. Taking this into consideration, the development of new therapies for wound healing requires immediate attention. Ethnopharmacological studies performed in different countries have shown the use of several plants from the Asteraceae family as wound-healing agents. Evidences gained from the traditional medicine have opened new ways for the development of novel and more efficient therapies based on the pharmacological properties of these plants. In this article, we discuss the literature data on the use of Asteraceae plants for the treatment of wounds, based on the ethnopharmacological relevance of each plant. Special attention was given to studies showing the mechanisms of action of Asteraceae-derived compounds and clinical trials. Ageratina pichinchensis (Kunth) R.M. King and H. Rob. and Calendula officinalis L. preparations/compounds were found to show good efficacy when assessed in clinical trials of complicated wounds, including venous leg ulcers and foot ulcers of diabetic patients. The compounds silibinin [from Silybum marianum (L.) Gaertn.] and jaceosidin (from Artemisia princeps Pamp.) were identified as promising compounds for the treatment of wounds. Overall, we suggest that Asteraceae plants represent important sources of compounds that may act as new and efficient healing products.

Rheumatoid arthritis (RA), an inflammatory disease of the joints, affects 1% of the adult population. Sulforaphane (SFN), a natural compound found in cruciferous vegetables, acts as a potent antioxidant. This compound was shown to mediate anti-inflammatory and anti-nociceptive actions in models of neuropathy and osteoarthritis. Additionally, in vitro studies suggest SFN inhibits macrophage- and synoviocyte-mediated responses. Here, we investigated the effects of SFN in a mouse monoarthritis model. Monoarthritis was induced in female C57BL/6 mice (10-weeks old) by an intra-articular injection of CFA (10 μg/10 μl) into the ipsilateral knee joint. PBS (contralateral)-injected joints were used as controls. From day 4 post-monoarthritis induction, mice received either vehicle (3% DMSO in saline, i.p.) or SFN (10 mg/kg, i.p.) twice daily for 3 days. Mechanical allodynia and hyperalgesia were evaluated by using Von Frey Filaments (0.4 g and 0.6 g, respectively). Knee joint thickness was measured to assess oedema formation. Thioredoxin reductase (TrxR) levels and cell populations were evaluated in synovial fluid samples. CFA-injection in vehicle controls, induced knee joint pain and oedema in comparison with PBS-treated joints. SFN had no effects on pain, but reduced CFA-induced knee joint swelling. SFN also increased the levels of TrxR in the synovial fluid of CFA-injected joints, which was accompanied by increased numbers of Ly6C+ and Ly6G+ cells. Our results show that SFN attenuates joint inflammation by modulating inflammatory cell accumulation into the knee joint and TrxR expression.