Bioactive compounds from the leaves of Maytenus ilicifolia Mart. ex Reissek: Inhibition of LDL oxidation, glycation, lipid peroxidation, target enzymes, and microbial growth.

ETHNOPHARMACOLOGICAL RELEVANCE: Maytenus ilicifolia Mart. ex Reissek, a medicinal plant used for treating gastritis, ulcers, and gastric disorders, possesses therapeutic properties attributed to diverse leaf compounds-terpenoids, alkaloids, flavonoids, phenols, and tannins, reflecting the ethnopharmacological knowledge of traditional users. AIMS OF THE STUDY: We aimed to assess the antioxidant and antiglycant capacities of Maytenus ilicifolia's ethanolic extract and organic fractions, identify bioactive compounds through HPLC-MS/MS analysis, and conduct phytochemical assessments. We also assessed their potential to inhibit digestive and cholinesterase enzymes, mitigate oxidation of human LDL and rat hepatic tissue, and examine their antimicrobial and cytotoxic properties. MATERIALS AND METHODS: Organic fractions (hexane - HF-Mi, dichloromethane - DMF-Mi, ethyl acetate - EAF-Mi, n-butanol - BF-Mi, and hydromethanolic - HMF-Mi) were obtained via liquid-liquid partitioning. Antioxidant (DPPH, FRAP, ORAC) and antiglycant (BSA/FRU, BSA/MGO, ARG/MGO/LDL/MGO models) capacities were tested. Phytochemical analysis employed HPLC-MS/MS. We also studied the inhibitory effects on α-amylase, acetylcholinesterase, butyrylcholinesterase, human LDL and rat hepatic tissue oxidation, antimicrobial activity, and cytotoxicity against RAW 264.7 macrophages. RESULTS: HPLC-ESI-MS/MS identified antioxidant compounds such as catechin, quercetin, and kaempferol derivatives. Ethanolic extract (EE-Mi) and organic fractions demonstrated robust antioxidant and antiglycant activity. EAF-Mi and BF-Mi inhibited α-amylase (2.42 µg/mL and 7.95 µg/mL) compared to acarbose (0.144 µg/mL). Most organic fractions exhibited ∼50% inhibition of acetylcholinesterase and butyrylcholinesterase, rivaling galantamine and rivastigmine. EAF-Mi, BF-Mi, and EE-Mi excelled in inhibiting lipid peroxidation. All fractions, except HMF-Mi, effectively countered LDL oxidation, evidenced by the area under the curve. These fractions protected LDL against lipid peroxidation. CONCLUSION: This study unveils Maytenus ilicifolia's ethanolic extract and organic fractions properties. Through rigorous analysis, we identify bioactive compounds and highlight their antioxidant, antiglycant, enzyme inhibition, and protective properties against oxidative damage. These findings underline its significance in modern pharmacology and its potential applications in healthcare.

Efficacy of lapachol on treatment of cutaneous and visceral leishmaniasis.

Leishmaniasis is one of the most important neglected diseases worldwide. It is a life-threatening disease and causes significant morbidity, long-term disability, and early death. Treatment involves disease control or use of intervention measures, although the currently used drugs require long-lasting therapy, and display toxicity and reduced efficacy. The use of natural products isolated from plants, such as lapachol, an abundant naphthoquinone naturally occurring in South American Handroanthus species (Tabebuia, Bignoniaceae), is a promising option for the treatment of leishmaniasis. In this study, we investigated the leishmanicidal activity of lapachol in vitro and in vivo against Leishmania infantum and L. amazonensis, causative agents of visceral and cutaneous leishmaniasis, respectively. Low cytotoxicity in HepG2 cells (3405.8 ±â€¯261.33 µM), good anti-Leishmania activity, and favorable selectivity indexes (SI) against promastigotes of both L. amazonensis (IC50 = 79.84 ±â€¯9.10 µM, SI = 42.65) and L. infantum (IC50 = 135.79 ±â€¯33.04 µM, SI = 25.08) were observed. Furthermore, anti-Leishmania activity assays performed on intracellular amastigotes showed good activity for lapachol (IC50 = 191.95 µM for L. amazonensis and 171.26 µM for L. infantum). Flow cytometric analysis demonstrated that the cytotoxic effect of lapachol in Leishmania promastigotes was caused by apoptosis-like death. Interestingly, the in vitro leishmanicidal effect of lapachol was confirmed in vivo in murine models of visceral and cutaneous leishmaniasis, as lapachol (25 mg/kg oral route for 24 h over 10 days) was able to significantly reduce the parasitic load in skin lesions, liver, and spleen, similar to amphotericin B, the reference drug. These results reinforce the therapeutic potential of lapachol, which warrants further investigations as an anti-leishmaniasis therapeutic.