22ß-hydroxytingenone induces apoptosis and suppresses invasiveness of melanoma cells by inhibiting MMP-9 activity and MAPK signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: 22ß-hydroxytingenone (22-HTG) is a quinonemethide triterpene isolated from Salacia impressifolia (Miers) A. C. Smith (family Celastraceae), which has been used in traditional medicine to treat a variety of diseases, including dengue, renal infections, rheumatism and cancer. However, the anticancer effects of 22-HTG and the underlying molecular mechanisms in melanoma cells have not yet been elucidated. AIM OF THE STUDY: The present study investigated apoptosis induction and antimetastatic potencial of 22-HTG in SK-MEL-28 human melanoma cells. MATERIALS AND METHODS: First, the in vitro cytotoxic activity of 22-HTG in cultured cancer cells was evaluated. Then, cell viability was determined using the trypan blue assay in melanoma cells (SK-MEL-28), which was followed by cell cycle, annexin V-FITC/propidium iodide assays (Annexin/PI), as well as assays to evaluate mitochondrial membrane potential, production of reactive oxygen species (ROS) using flow cytometry. Fluorescence microscopy using acridine orange/ethidium bromide (AO/BE) staining was also performed. RT-qPCR was carried out to evaluate the expression of BRAF, NRAS, and KRAS genes. The anti-invasiveness potential of 22-HTG was evaluated in a three-dimensional (3D) model of reconstructed human skin. RESULTS: 22-HTG reduced viability of SK-MEL-28 cells and caused morphological changes, as cell shrinkage, chromatin condensation, and nuclear fragmentation. Furthermore, 22-HTG caused apoptosis, which was demonstrated by increased staining with AO/BE and Annexin/PI. The apoptosis may have been caused by mitochondrial instability without the involvement of ROS production. The expression of BRAF, NRAS, and KRAS, which are important biomarkers in melanoma development, was reduced by the 22-HTG treatment. In the reconstructed skin model, 22-HTG was able to decrease the invasion capacity of melanoma cells in the dermis. CONCLUSIONS: Our data indicate that 22-HTG has anti-tumorigenic properties against melanoma cells through the induction of cell cycle arrest, apoptosis and inhibition of invasiveness potential, as observed in the 3D model. As such, the results provide new insights for future work on the utilization of 22-HTG in malignant melanoma treatment.

In vitro and in vivo anti-leukemia activity of the stem bark of Salacia impressifolia (Miers) A. C. Smith (Celastraceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Salacia impressifolia (Miers) A. C. Smith (family Celastraceae) is a traditional medicinal plant found in the Amazon Rainforest known as "miraruíra", "cipó-miraruíra" or "panu" and is traditionally used to treat dengue, flu, inflammation, pain, diabetes, male impotency, renal affections, rheumatism and cancer. AIM OF THE STUDY: The aim of this study was to investigate in vitro and in vivo anti-leukemia activity of the stem bark of S. impressifolia in experimental models. MATERIALS AND METHODS: The in vitro cytotoxic activity of extracts, fractions and quinonemethide triterpenes (22-hydroxytingenone, tingenone and pristimerin) from the stem bark of S. impressifolia in cultured cancer cells was determined. The in vivo antitumor activity of the ethyl acetate extract (EAE) and of its fraction (FEAE.3) from the stem bark of S. impressifolia was assessed in C.B-17 severe combined immunodeficient (SCID) mice engrafted with human promyelocytic leukemia HL-60 cells. RESULTS: The extract EAE, its fraction FEAE.3, and quinonemethide triterpenes exhibited potent cytotoxicity against cancer cell lines, including in vitro anti-leukemia activity against HL-60 and K-562 cells. Moreover, extract EAE and its fraction FEAE.3 inhibited the in vivo development of HL-60 cells engrafted in C.B-17 SCID mice. Tumor mass inhibition rates were measured as 40.4% and 81.5% for the extract EAE (20 mg/kg) and for its fraction FEAE.3 (20 mg/kg), respectively. CONCLUSIONS: Ethyl acetate extract and its fraction from the stem bark of S. impressifolia exhibit in vitro and in vivo anti-leukemia activity that can be attributed to their quinonemethide triterpenes. These data confirm the ethnopharmacological use of this species and may contribute to the development of a novel anticancer herbal medicine.

Bioatividade de moléculas isoladas de Trichilia pallida Swartz (Meliaceae) sobre Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) / Bioactivity of Trichilia pallida Swartz (Meliaceae) derived molecules on Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

A partir do extrato em diclorometano (DIC) de folhas e frutos de Trichilia pallida Swartz, objetivou-se fazer o isolamento e identificação de substâncias com atividade inseticida sobre a traça-do-tomateiro, Tuta absoluta (Meyrick). Do extrato em DIC de folhas de T. pallida foram isolados os triterpenos 24-metilenocicloarta-3β-ol (TRIT-1), 24-metilenocicloarta-3β-26-diol (TRIT-2) e cicloarta-23-eno-3β,25-diol (TRIT-3), os esteróides 24-metileno-3,22-diidroxicolesterol (EST-1), 24-metilenocolesterol (EST-2) e 24-metileno-3β,4β,22-triidroxicolesterol (EST-3), além do limonóide gedunina (LIM) obtido de frutos da planta. As substâncias foram dissolvidas em acetona e pulverizadas a 0,1% em folíolos de tomateiro infestados com lagartas recém-eclodidas. Foram avaliadas a mortalidade de lagartas aos quinto e nono dias após a infestação, duração e sobrevivência das fases de larva e pupa, peso de pupas e porcentagem de adultos deformados. TRIT-1, EST-1 e LIM foram as moléculas que apresentaram maior atividade sobre T. absoluta, alongando o desenvolvimento larval e reduzindo a sobrevivência dessa fase.

Dichloromethane (DIC) leaf and fruit extracts of Trichiliapallida Swartz were obtained for the isolation and identification of molecules with insecticidal activity against the tomato leafminer, Tuta absoluta (Meyrick). DIC leaf extracts of T. pallida yielded six compounds, the triterpenes 24-methylenecycloarta-3β-ol (TRIT-1), 24-methylenecycloarta-3β-26-diol (TRIT-2) and cycloarta-23-eno-3β,25-diol (TRIT-3), the sterols 24-methylene-3,22-dihydroxycholesterol (EST-1), 24-methylenecholesterol (EST-2) and 24-methylene-3β,4β,22-trihydroxycholesterol (EST-3), while the fruit extract yielded the limonoid gedunine (LIM). These molecules were dissolved in acetone and sprayed at 0.1% on tomato leaflets infested with newly-hatched larvae. Larval mortality at day 5 and 9 after infestation, larval and pupal developmental time and survival, pupal weight and adult malformation were evaluated. TRIT-1, EST-1 and LIM were the most effective against T. absoluta due to larval development arrestment and reduced larval survivorship.

[Bioactivity of Trichilia pallida Swartz (Meliaceae) derived molecules on Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)]. / Bioatividade de moléculas isoladas de Trichilia pallida Swartz (Meliaceae) sobre Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae).

Dichloromethane (DIC) leaf and fruit extracts of Trichiliapallida Swartz were obtained for the isolation and identification of molecules with insecticidal activity against the tomato leafminer, Tuta absoluta (Meyrick). DIC leaf extracts of T. pallida yielded six compounds, the triterpenes 24-methylenecycloarta-3beta-ol (TRIT-1), 24-methylenecycloarta-3beta-26-diol (TRIT-2) and cycloarta-23-eno-3beta,25-diol (TRIT-3), the sterols 24-methylene-3,22-dihydroxycholesterol (EST-1), 24-methylenecholesterol (EST-2) and 24-methylene-3beta,4beta,22-trihydroxycholesterol (EST-3), while the fruit extract yielded the limonoid gedunine (LIM). These molecules were dissolved in acetone and sprayed at 0.1% on tomato leaflets infested with newly-hatched larvae. Larval mortality at day 5 and 9 after infestation, larval and pupal developmental time and survival, pupal weight and adult malformation were evaluated. TRIT-1, EST-1 and LIM were the most effective against T. absoluta due to larval development arrestment and reduced larval survivorship.

Bioactivity of extracts and isolated compounds from Vitex polygama (Verbenaceae) and Siphoneugena densiflora (Myrtaceae) against Spodoptera frugiperda (Lepidoptera: Noctuidae).

The effects of crude extracts, fractions and isolated compounds from Vitex polygama Cham. and Siphoneugena densiflora Berg were evaluated on the development of Spodoptera frugiperda JE Smith, a destructive insect pest of corn and several other crops. The extracts and fractions were incorporated into an artificial diet at 1 mg g(-1) and offered to the insect during its larval stage. Length and viability of larval and pupal stages as well as pupal weight were assessed. Isolated compounds were tested through superficial contamination of the diet at 0.1 mg g(-1). Weight and viability of ten-day-old larvae were determined. Methanolic and hydroalcoholic S. densiflora extracts caused 100% larval mortality, while leaf and fruit hydroalcoholic extracts from V. polygama were the most active. Among the isolated compounds, flavonoids presented the best insecticidal results, and tannins the best larval growth inhibition.