Ethyl Acetate Fraction of Bixa orellana and Its Component Ellagic Acid Exert Antibacterial and Anti-Inflammatory Properties against Mycobacterium abscessus subsp. massiliense.

Mycobacterium abscessus subsp. massiliense (Mabs) causes chronic infections, which has led to the need for new antimycobacterial agents. In this study, we investigated the antimycobacterial and anti-inflammatory activities of the ethyl acetate fraction of Bixa orellana leaves (BoEA) and ellagic acid (ElAc). In silico analysis predicted that ElAc had low toxicity, was not mutagenic or carcinogenic, and had antimicrobial and anti-inflammatory activities. Apparently, ElAc can interact with COX2 and Dihydrofolate reductase (DHFR) enzymes, which could explain both activities. In vitro analysis showed that BoEA and ElAc exerted antimicrobial activity against Mabs (minimum inhibitory concentration of 1.56, 1.56 mg/mL and bactericidal concentration of 6.25, 3.12 mg/mL, respectively. Clarithromycin showed MIC and MBC of 1 and 6 µg/mL). Treatment with BoEA or ElAc increased survival of Tenebrio molitor larvae after lethal infection with Mabs and reduced carrageenan-induced paw edema in mice, around 40% of edema volume after the fourth hour, similarly to diclofenac. In conclusion, BoEA and ElAc exert antimicrobial effects against Mabs and have anti-inflammatory effects, making them potential sources of antimycobacterial drugs. The biological activities of ElAc may be due to its high binding affinities predicted for COX2 and DHFR enzymes.

Effects of Bothrops alternatus venom in zebrafish: a histopathological study.

Zebrafish is an excellent model organism for studying tissue alterations caused by Bothrops alternatus venom (BAV) and for screening new anti-venom drugs. To study tissue alterations following exposure to BAV and the roles that glucocorticoids play in these tissue reactions, zebrafish were randomly divided into five groups: the free injection control group (FIC), the phosphate-buffered saline injection control group (PIC), the venom injected group (VI), the group treated with dexamethasone 1 h before venom injection (D1hBVI) and the group treated with dexamethasone 1 h after venom injection (D1hAVI). The concentration of BAV injected was 0.13 mg/mL and each fish received an injection of 20 µL. Body weight measurements and histopathological characteristics of the gills, kidneys, liver, and intestine were determined. Histopathological analyses showed necrosis, inflammation and weight gain in animals that received BAV. The histological alteration indices of the gills, liver, kidneys, and intestines were statistically higher in the animal groups treated with BAV. These alteration indices were lower in the D1hBVI and D1hAVI groups compared to the group treated with BAV alone. The D1hBVI group is presented with minor alterations. A significant difference in the histological alterations index was observed in the intestinal tissue of the FIC group compared to the PIC group. Cumulatively, zebrafish may serve as a useful biomarker for alterations induced by BAV. Interestingly, dexamethasone reduced the damage caused by BAV in the organs studied, which suggests that zebrafish might be useful for screening new drugs that can mitigate tissue damage caused by snakebites.

Study of the non-clinical healing activities of the extract and gel of Portulaca pilosa L. in skin wounds in wistar rats: A preliminary study.

INTRODUCTION: Portulaca pilosa L., belonging to the family Portulacaceae, is a common herbaceous plant in the Americas and in the Amazon, is popularly known as love-grown and is traditionally used as an aid in the treatment of burns, buds, insect bites and wound healing. This study aims to evaluate the non-clinical topical healing activity of the P. pilosa gel (GPP) and the propyleneglycol extract of P. pilosa (EPP) in Wistar rats. METHODS: For the healing activity, wistar rats were divided into the following groups: negative control (GVE - vehicle, 150mg/kg), positive control (Fibrinase®- FIB, 100U/kg), Portulaca pilosa gel 10%, (GPP, 150mg/kg), and propylenglycollic extract of Portulaca pilosa (EPP, 150 mg/kg), which were submitted to a surgical procedure to obtain the wounds, and were treated topically for 7days. After treatment, the treated area was removed and a histopathological analysis was performed. RESULTS: The EPP when analyzed in HPLC was able to identify the presence of gallic acid. EPP significantly modulated the tissue inflammatory response, presenting low number of inflammatory cells in the histopathological study. Treatment with EPP and GPP significantly stimulated angiogenesis and this response was superior to the fibrinase® group. Treatment with EPP and GPP significantly stimulated the proliferation of fibroblasts. The groups treated with EPP and GPP presented an organization pattern of the epidermis and dermis better than the control group, with a mild inflammatory process, with fibroblast proliferation and increased formation of collagen fibers. CONCLUSION: Thus, from the results obtained it can be suggested that the phytochemical marker of the P. pilosa species for healing activity is gallic acid and, together with the macroscopic and microscopic findings triggered by the topical applications of EPP and GPP, it can be concluded that this plant species has topical healing activity, with great potential for use, since this pharmacological action is associated with a possible topical anti-inflammatory activity.