New annonaceous acetogenins from Rollinia mucosa

Annonaceous Acetogenins Synergistically Inhibit Hepatocellular Carcinoma with Sorafenib

Sorafenib was first approved as the standard treatment for advanced hepatocellular carcinoma (HCC). Despite providing an advantage in terms of patient survival, sorafenib has shown poor clinical efficacy and severe side effects after long-term treatment. Thus, combination treatment is a potential way to increase the effectiveness and reduce the dose-limiting toxicity of sorafenib. Extracts of the seeds of Annona montana have shown synergistic antitumor activity with sorafenib, and seven annonaceous acetogenins, including three new acetogenins, muricin P (2), muricin Q (3), and muricin R (4), were isolated from the extracts by bioguided fractionation and showed synergy with sorafenib. The structures of these compounds were determined using spectroscopic and chemical methods. Annonacin (1) and muricin P (2), which reduced intracellular ATP levels and promoted apoptosis, exhibited synergistic cytotoxicity with sorafenib in vitro. In vivo, annonacin (1) displayed synergistic antitumor activity by promoting tumor cell apoptosis. Moreover, the potential mechanism of annonacin (1) was predicted by transcriptomic analysis, which suggested that SLC33A1 is a potential target in HCC. Annonacin (1) might be a novel candidate for combination therapy with sorafenib against advanced HCC.

Functional and nutritional properties of selected Amazon fruits: A review

This review reports the nutritional, phytochemical compounds and biological properties of 4 fruits commonly consumed by people living in Amazon region, namely Biribá (Rollinia mucosa Jacq.), Rambutan (Nephelium lappaceum L.), Pupunha (Bactris gasipaes Kunth) and Tucumã (Astrocaryum aculeatum Meyer). These fruits have been high held nutritional, functional and economic potential and contribute to the daily intake of nutrients, energy and bioactive compounds by people living in Amazon rainforest region. Phytochemical compounds with biological properties were detected in these fruits, for instance (but not limited to), annonaceous acetogenins in Biribá, geraniin and corilagin in Rambutan, rutin and catechin in Pupunha, and β-carotene and flavonoids in Tucumã. The biological properties of Biribá, Rambutan, Pupunha and Tucumã have been evaluated by in vitro and in vivo assays, especially antioxidant and antimicrobial activities. Therefore, these Amazonian fruits can be exploited by the food industry as a food and therapeutic plant-material to develop valuable products, such as medicine products and can be used as sources for obtaining compounds for the food, cosmetics and pharmaceutical applications.

Acetogenins from Annonaceae family. Their potential biological applications

The aim of this contribution has been to continue with the knowledge about newly isolated acetogenins from Annonaceae family for the last fifteen years. This review will report classification, extraction, isolation, elucidation of the structure, biological activities and mechanism of action of such interesting natural products. In fact, out of the 532 compounds reviewed, 115 previously non-described annonaceous acetogenins have been added to the list of isolated compounds from 2005 to May 2019.

Acetogenins from Annonaceae

In recent decades, annonaceous acetogenins have become highly studied plant secondary metabolites in terms of their isolation, structure elucidation, synthesis, biological evaluation, mechanism of action, and toxicity. The aim of the present contribution is to summarize chemical and biological reports published since 1997 on annonaceous acetogenins and synthetic acetogenin mimics. The compounds are considered biologically in terms of their cytotoxicity for cancer cell lines, neurotoxicity, pesticidal effects, and miscellaneous activities.

Antiproliferative acetogenins from a Uvaria sp. from the Madagascar dry forest

Investigation of the endemic Madagascan plant Uvaria sp. for antiproliferative activity against the A2780 ovarian cancer cell line led to the isolation of two new acetogenins. The structures of these two compounds were elucidated on the basis of analysis of their 1D and 2D NMR spectra, circular dichroism, and mass spectrometric data, together with chemical modification. The two acetogenins display weak antiproliferative activity against the A2780 ovarian cancer, the A2058 melanoma, and the H522 lung cancer cell lines.

Antiprotozoal and cytotoxic activities in vitro of Colombian Annonaceae

Ethnobotanical and chemotaxonomical studies for antiparasitic activity of Colombian Annonaceae were carried out. In vitro antiprotozoal activity of 36 extracts obtained from six different species was determined against promastigotes of three Leishmania species, epimastigotes of Trypanosoma cruzi and both chloroquine sensitive (F32) and resistant (W2) Plasmodium falciparum. Cytotoxic activity was evaluated in U-937 cells. Active extracts were selected according their selectivity index (SI). Extracts from Annona muricata, Rollinia exsucca, Rollinia pittieri and Xylopia aromatica were active against Leishmania spp. and Trypanosoma cruzi showing IC50 values lower than 25 microg/ml. Hexane extract from Rollinia pittieri leaves was the most selective against Trypanosoma cruzi and Leishmania spp. (IS=10 and 16, respectively). The extracts from Desmopsis panamensis, Pseudomalmea boyacana, Rollinia exsucca and Rollinia pittieri showed good antiplasmodial activity (IC50 < 10 microg/ml). No correlation between antiplasmodial activity and inhibition of beta-hematin production was found. The present study gives specific and useful information about antiprotozoal and cytotoxic activities of some Annonaceae extracts. Results presented here also demonstrate which plants and/or plant parts could be useful in the treatment of leishmaniasis, Chagas' disease and malaria.

Novel cytotoxic monotetrahydrofuranic Annonaceous acetogenins from Annona montana

Four new monotetrahydrofuranic Annonaceous acetogenins, montalicins G (1) and H (2) and monlicins A (3) and B (4), and two new linear acetogenins, (+)-monhexocin (5) and (-)-monhexocin (6), as well as three known compounds, murisolin (7), 4-deoxyannomontacin (8), and muricatacin (9), were isolated from the seeds of Annona montana by high performance liquid chromatographic (HPLC) method. The absolute stereochemical structures of new isolates were elucidated and characterized by spectral and chemical methods. Interestingly, these compounds show special cytotoxicity against human hepatoma cells, Hep G2.

Acetogenins from Annonaceae: recent progress in isolation, synthesis and mechanisms of action

The aim of the present review is to summarise the knowledge about newly isolated acetogenins (ACGs) in the last six years. It will also report the total syntheses that have allowed either the confirmation or the revision of some structures, together with the biological activities and mechanism of action of such interesting natural products. In fact, of the 417 isolated compounds reviewed, over 176 have been added during the period from 1998 to 2004.

Bullatacin, a potent antitumor Annonaceous acetogenin, induces apoptosis through a reduction of intracellular cAMP and cGMP levels in human hepatoma 2.2.15 cells

Bullatacin, a potential antitumor Annonaceous acetogenin (AA), is isolated from the seed of the Formosa Annona atemoya. We reported previously that bullatacin inhibits the secretion of hepatitis B surface antigen from 2.2.15 cells (human hepatoma HepG2 cells transfected with hepatitis B virus DNA plasmid). In the present study, we determined cell apoptosis by using double-dye staining with fluorescein-isothiocyanate-labeled annexin V and propidium iodide. We found that bullatacin induced apoptosis in 2.2.15 cells in a time-dependent manner; the most significant apoptotic change appeared at 16 hr. Moreover, different concentrations (10(-3) to 1.0 microM) of bullatacin induced apoptosis in a concentration-dependent manner at 16 hr. The determination of intracellular cyclic AMP (cAMP) and cyclic GMP (cGMP) levels in 2.2.15 cells after exposure to bullatacin demonstrated that bullatacin caused both to decrease in a time- and concentration-dependent manner. A time course (0.33, 1, 6, 16, 24hr) study indicated that while both cAMP and cGMP levels decreased early (at 0.33 hr), the most dramatic decline appeared at 6 hr. Meanwhile, the inhibitory effect on cAMP and cGMP levels reached a maximum at 16 hr (90.5+/-3.2 and 47.3+/-12.8%, respectively). The concentration-dependent decrease of both cAMP and cGMP induced by bullatacin was parallel with the magnitude of apoptosis induced by various concentrations (10(-3) to 1.0 microM) of bullatacin. Additionally, the bullatacin-induced apoptosis was inhibited by the addition of cAMP and cGMP elevating agents (forskolin and S-nitrosoglutathione). Our results suggest that a decrease of both cAMP and cGMP levels may play a crucial role in bullatacin-induced apoptosis in 2.2.15 cells.

Antiplatelet activity of N-methoxycarbonyl aporphines from Rollinia mucosa

Bioassay-directed fractionation of the stems of Rollinia mucosa led to the isolation of new N-methoxycarbonyl aporphine alkaloids, romucosine A (1), romucosine B (2), romucosine C (3), and romucosine D (4), along with the known alkaloid, N-methoxylcarbonyl-nornuciferine (5). Alkaloids 1 and 4 exhibited significant inhibition of collagen, arachidonic acid, and platelet activating factor-induced platelet aggregation, and alkaloid 3 also showed an inhibitory effect on arachidonic acid induced platelet aggregation.