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.

Restricted Activation of the NF-κB Pathway in Individuals with Latent Tuberculosis Infection after HIF-1α Blockade.

Tuberculous granuloma formation is mediated by hypoxia-inducible factor 1 alpha (HIF-1α), and is essential for establishing latent tuberculosis infection (LTBI) and its progression to active tuberculosis (TB). Here, we investigated whether HIF-1α expression and adjacent mechanisms were associated with latent or active TB infection. Patients with active TB, individuals with LTBI, and healthy controls were recruited, and the expression of cytokine genes IL15, IL18, TNFA, IL6, HIF1A, and A20 in peripheral blood mononuclear cells (PBMCs) and serum vitamin D (25(OH)D3) levels were evaluated. Additionally, nuclear factor kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-α) levels were analyzed in PBMC lysates and culture supernatants, respectively, after HIF-1α blockade with 2-methoxyestradiol. We observed that IL-15 expression was higher in individuals with LTBI than in patients with active TB, while IL-18 and TNF-α expression was similar between LTBI and TB groups. Additionally, serum 25(OH)D3 levels and expression of IL-6, HIF1A, and A20 were higher in patients with active TB than in individuals with LTBI. Moreover, PBMCs from individuals with LTBI showed decreased NF-κB phosphorylation and increased TNF-α production after HIF-1α blockade. Together, these results suggest that under hypoxic conditions, TNF-α production and NF-κB pathway downregulation are associated with the LTBI phenotype.

Compounds isolated from Bixa orellana: evidence-based advances to treat infectious diseases / Compuestos aislados de Bixa orellana: avances basados en la evidencia para tratar enfermedades infecciosas

SUMMARY Bixa orellana L. is a native plant from Brazil, but it is also present in other tropical countries such as Peru, Colombia, Ecuador, Mexico, Indonesia, India and East Africa. It is popularly known as Urucum in Brazil. This review shows the potential of bioactive compounds derived from B. orellana to treat infectious diseases due their antimicrobial and antioxidant properties. This plant is also related as an antiinflammatory agent for treatment of pulmonary diseases, or even as eye drops for redness. Its leaves are used for treatment of snakebite, diarrhea, gonorrhea, hepatitis, gastritis, diuretic, antipyretic, and for skin disease. This popular knowledge has encouraged the identification of bioactive compounds in this plant. Compounds as β-cryptoxanthin, geranylgeraniol, lutein, procyanidin B2, procyanidin B3, ellagi tannin isomer and ellagic acid deoxyhexose have been described. These compounds inhibited pathogenic microorganisms such as bacteria, fungi, protozoan and viruses. In addition, some compounds with anti-inflammatory and antioxidant activities were also described. In this sense, B. orellana is a promising source of compounds that could be applied in antimicrobial therapy. This review work may help in the understanding and incentive of new research for antimicrobial discoveries using different B. orellana compounds.

RESUMEN Bixa orellana L. es una planta nativa de Brasil, pero también está presente en otros países tropicales como Perú, Colombia, Ecuador, México, Indonesia, India y África Oriental. Es conocida popularmente como Urucum en Brasil. Esta revisión expone el potencial de los compuestos bioactivos derivados de B. orellana para tratar enfermedades debido a sus propiedades antimicrobianas y antioxidantes. Esta planta también está relacionada como un agente antiinflamatorio para el tratamiento de enfermedades pulmonares e incluso como gotas para los ojos para el enrojecimiento. Sus hojas se utilizan para el tratamiento de la mordedura de serpiente, diarrea, gonorrea, hepatitis, gastritis, diuréticos, antipiréticos y para enfermedades de la piel. Ese conocimiento popular ha fomentado la identificación de compuestos bioactivos en esa planta. Los compuestos β-criptoxantina, geranilgeraniol, luteína, procianidina B2, procianidina B3, isómero elagitanino y ácido elágico desoxihexosa inhibieron microorganismos patógenos como bacterias, hongos, protozoos y virus. En ese sentido, B. orellana es una fuente prometedora de compuestos que podrían aplicarse en la terapia antimicrobiana. Este trabajo de revisión puede ayudar a comprender e incentivar nuevas investigaciones para los descubrimientos de antimicrobianos que utilizan diferentes compuestos de B. orellana.