Enyne acetogenins from Porcelia macrocarpa displayed anti-Trypanosoma cruzi activity and cause a reduction in the intracellular calcium level.

Natural products are a promising source of new compounds with a wide spectrum of pharmacological properties, including antiprotozoal activities. Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is one of several neglected tropical diseases with reduced options for treatment, which presents limitations such as toxicity and ineffectiveness in the chronic stage of the disease. Aiming to investigate the Brazilian flora for the discovery of new anti-T. cruzi compounds, the MeOH extract from Porcelia macrocarpa R.E. Fries (Annonaceae) fruit peels displayed potent activity against trypomastigotes and intracellular amastigotes and was subjected to bioactivity-guided fractionation. Using different chromatographic steps, a fraction composed of a mixture of four new chemically related acetogenins was obtained. The compounds were characterized as (2S*,3R*,4R*)-3-hydroxy-4-methyl-2-(n-octadeca-13',17'-dien-11'-inil)butanolide (1), (2S*,3R*,4R*)-3-hydroxy-4-methyl-2-(n-eicosa-13',19'-dien-11'-inil)butanolide (2), (2S*,3R*,4R*)-3-hydroxy-4-methyl-2-(n-octadec-13'-en-11'-inil)butanolide (3), and (2S*,3R*,4R*)-3-hydroxy-4-methyl-2-(n-eicosa-13'-en-11'-inil)butanolide (4) by NMR analysis and UHPLC/ESI-HRMS data. The mixture of compounds 1-4, displayed an EC50 of 4.9 and 2.5 µg/mL against trypomastigote and amastigote forms of T. cruzi, respectively, similar to the standard drug benznidazole (EC50 of 4.8 and 1.4 µg/mL). Additionally, the mixture of compounds 1-4 displayed no mammalian toxicity for murine fibroblasts (CC50 > 200 µg/mL), resulting in a SI > 40.8 and > 83.3 against trypomastigotes and amastigotes, respectively. Based on these results, the mechanism of action of this bioactive fraction was investigated. After a short-time incubation with the trypomastigotes, no alterations in the cell membrane permeability were observed. However, it was verified a decrease in the intracellular calcium of the parasites, without significant pH variations of the acidocalcisomes. The intracellular damages were followed by an upregulation of the reactive oxygen species and ATP, but no depolarization effects were observed in the mitochondrial membrane potential. These data suggest that the mixture of compounds 1-4 caused an irreversible oxidative stress in the parasites, leading to death. If adequately studied, these acetogenins can open new insights for the discovery of new routes of death in T. cruzi.

Annonaceous Acetogenin Mimic AA005 Inhibits the Growth of TNBC MDA-MB-468 Cells by Altering Cell Energy Metabolism.

Triple-negative breast cancer (TNBC) is a serious health issue for women worldwide and there is still no suitable treatment option. AA005, a structurally simplified mimic of natural Annonaceous acetogenins, presents outstanding properties with impressive cytotoxicity and cell-type selective actions. The present study was aimed at evaluating the potential of AA005 as a therapeutic agent for TNBC. AA005 potently inhibited the growth of TNBC cells at 50 nM level. Inspired by the finding of the phosphatase and tensin homologue (PTEN) tumor suppressor, the effect of AA005 on aerobic glycolysis was investigated in TNBC MDA-MB-468 cells. A short-term AA005 exposure markedly suppressed mitochondrial function in MDA-MB-468 cells, thus activating the aerobic glycolysis to lessen the risk of decreased ATP generation in mitochondria. Prolonging the incubation time of AA005 clearly weakened the aerobic glycolysis in the cells. This was in part attributed to the PI3K-AKT pathway inactivation and subsequent declined glucose uptake. As a consequence, the energy supply was completely cut from the two major energy-producing pathways. Further experiments showed that AA005 resulted in irreversible damage on cell activity including cell cycle and growth, inducing mitochondrial oxidative stress and ultimately leading to cell death. In addition, the in vivo therapeutic efficacy of AA005 was proved on 4T1 xenograft tumor mice model. Our data demonstrate that AA005 exhibited a great potential for future clinical applications in TNBC therapy.

Pharmacological Activities of Soursop (Annona muricata Lin.).

Soursop (Annona muricata Lin.) is a plant belonging to the Annonaceae family that has been widely used globally as a traditional medicine for many diseases. In this review, we discuss the traditional use, chemical content, and pharmacological activities of A.muricata. From 49 research articles that were obtained from 1981 to 2021, A.muricata's activities were shown to include anticancer (25%), antiulcer (17%), antidiabetic (14%), antiprotozoal (10%), antidiarrhea (8%), antibacterial (8%), antiviral (8%), antihypertensive (6%), and wound healing (4%). Several biological activities and the general mechanisms underlying the effects of A.muricata have been tested both in vitro and in vivo. A.muricata contains chemicals such as acetogenins (annomuricins and annonacin), alkaloids (coreximine and reticuline), flavonoids (quercetin), and vitamins, which are predicted to be responsible for the biological activity of A.muricata.

An Overview of the Chemical Characteristics, Bioactivity and Achievements Regarding the Therapeutic Usage of Acetogenins from Annona cherimola Mill.

Annona cherimola Mill., or the custard apple, is one of the species belonging to the Annonaceae family, is widely used in traditional medicine, and has been reported to be a valuable source of bioactive compounds. A unique class of secondary metabolites derived from this family are Annonaceous acetogenins, lipophilic polyketides considered to be amongst the most potent antitumor compounds. This review provides an overview of the chemical diversity, isolation procedures, bioactivity, modes of application and synthetic derivatives of acetogenins from A. cherimola Mill.

Non-targeted metabolomic analysis on multidrug resistance hepatocellular carcinoma cell and reversal effect of annonaceous acetogenins.

Multidrug-resistance (MDR) has been shown to play a critical role in the development of many diseases. In this study, we used metabolomic method to evaluate the MDR in hepatocellular carcinoma, and investigate regulatory of annonaceous acetogenins on MDR of hepatocellular carcinoma. Multivariate statistical analysis revealed that the MDR of SMMC 7721 together with changes in glutathione metabolism, arginine and proline metabolism, sphingolipid metabolism. Annonaceous acetogenins impact these metabolism pathways. Metabolic pathway analysis coupled with stoichiometry analysis can be an effective tool to understand MDR mechanism and to potentially find new MDR reversal agents.

Annona species (Annonaceae): a rich source of potential antitumor agents?

Plants have provided the basis of traditional medicine systems throughout the world for thousands of years and continue to yield molecules for new remedies. We analyzed studies published from 2009 to 2016 on the Annona species (Annonaceae), including A. coriacea, A. crassifolia, A. hypoglauca, A. muricata, A. squamosa, A. sylvatica, and A. vepretorum, as sources of potential antitumor agents. Here, we report and discuss the mechanisms of action and structure-activity relationships of the most active Annona constituents. Annonaceous acetogenins are one of the most promising classes of natural products, owing to their potential antitumor activity. However, their neurotoxicity should not be underestimated.

Annonaceous acetogenins mediated up-regulation of Notch2 exerts growth inhibition in human gastric cancer cells in vitro.

BACKGROUND: Gastric cancer (GC) is a global health problem because of limited treatments and poor prognosis. Annonaceous acetogenins (ACGs) has been reported to exert anti-tumorigenic effects in cancer, yet the mechanism underlying its effects on GC remains largely unknown. Notch signaling plays a critical role in cell proliferation, differentiation and apoptosis. Therefore, it may contribute to the development of GC. This study aims to explore the role of Notch2 in ACGs' activities in GC cells. RESULTS: ACGs inhibited GC cells' viability in a dose dependent manner and led to cell apoptosis and cell cycle arrest in G0/G1 phase with an increased Notch2 expression. Additionally, Notch2 siRNA reduced ACGs-induced cell growth inhibition while Notch2 cDNA transfection did the opposite. MATERIALS AND METHODS: ACGs were administrated in GC cells and cell proliferation was assayed by MTS, cell apoptosis and cell cycle were detected by flow cytometry. Additionally, the expression of Notch2 and the downstream target Hes1 were identified by Western blot. Furthermore, Notch2-siRNA transfection and Notch2-cDNA were performed to investigate the role of Notch2 in the antitumor effect of ACGs. CONCLUSIONS: Up-regulation of Notch2 by ACGs is a potential therapeutic strategy for GC.

Mechanistic Study of Tetrahydrofuran- acetogenins In Triggering Endoplasmic Reticulum Stress Response-apotoposis in Human Nasopharyngeal Carcinoma.

For past three decades, numerous studies have elucidated the antiproliferative effects of acetogenins in hopes of developing a new class of clinical anticancer agents. However, clear and definitive action mechanisms of acetogenins were less clarified. In the present study, three tetrahydrofuran (THF)-containing acetogenins were found to have potent and selective antiproliferative activity against human nasopharyngeal carcinoma (NPC) cell lines and their methotrexate-resistant counterparts. The THF-containing acetogenins induced G2/M phase arrest, mitochondrial damage and apoptosis, and increased cytosolic and mitochondrial Ca2+ in NPCs. Microarray analysis of NPC-TW01 cells treated with squamostatin A, a non-adjacent bis-THF acetogenin, demonstrated an increased endoplasmic reticulum (ER)-stress response (ESR). Enhanced ESR in squamostatin A-treated cells was confirmed by real-time PCR, Western blot and shRNA gene knockdown experiments. Although our results showed that squamostatin A-induced ESR was independent of extracellular Ca2+, the presence of extracellular Ca2+ enhanced the antiproliferative effect of acetogenins. In vivo analyses demonstrated that squamostatin A showed good pharmacokinetic properties and significantly retarded NPC tumor growth in the xenograft mouse model. Conclusively, our work demonstrates that acetogenins are effective and selective inducers of the ESR that can block NPC proliferation, and illustrate a previously unappreciated antitumor mechanism of acetogenins that is effective against nasopharyngeal malignancies.

Isolation and chemical identification of lipid derivatives from avocado (Persea americana) pulp with antiplatelet and antithrombotic activities.

Platelets play a pivotal role in physiological hemostasis. However, in coronary arteries damaged by atherosclerosis, enhanced platelet aggregation, with subsequent thrombus formation, is a precipitating factor in acute ischemic events. Avocado pulp (Persea americana) is a good source of bioactive compounds, and its inclusion in the diet as a source of fatty acid has been related to reduced platelet aggregability. Nevertheless, constituents of avocado pulp with antiplatelet activity remain unknown. The present study aims to characterize the chemical nature of avocado constituents with inhibitory effects on platelet aggregation. Centrifugal partition chromatography (CPC) was used as a fractionation and purification tool, guided by an in vitro adenosine diphosphate (ADP), arachidonic acid or collagen-platelet aggregation assay. Antiplatelet activity was initially linked to seven acetogenins that were further purified, and their dose-dependent effects in the presence of various agonists were contrasted. This process led to the identification of Persenone-C (3) as the most potent antiplatelet acetogenin (IC50=3.4 mM) among the evaluated compounds. In vivo evaluations with Persenone A (4) demonstrated potential protective effects against arterial thrombosis (25 mg kg⁻¹ of body weight), as coagulation times increased (2-fold with respect to the vehicle) and thrombus formation was attenuated (71% versus vehicle). From these results, avocado may be referred to as a functional food containing acetogenin compounds that inhibit platelet aggregation with a potential preventive effect on thrombus formation, such as those that occur in ischaemic diseases.

Anticancer effect of total annonaceous acetogenins on hepatocarcinoma.

OBJECTIVE: To confirm the anticancer effect of total annonaceous acetogenins (TAAs) abstracted from Annona squamosa Linn. on human hepatocarcinoma. METHODS: The inhibitory effect of TAAs was demonstrated in H22-bearing mice. The potency of TAAs was confirmed as its 50% inhibiting concentration (IC50) on Bel-7402 cell under Sulfur Rhodamine B staining. Both underlying mechanisms were explored as cellular apoptosis and cell cycle under flow cytometry. Mitochondrial and recipient apoptotic pathways were differentiated as mitochondrial membrane potential under flow cytometry and caspases activities under fluorescence analysis. RESULTS: The inhibitory rate of TAAs in mice was 50.98% at 4 mg/kg dose. The IC50 of TAAs on Bel-7402 was 20.06 µg/mL (15.13-26.61µg/mL). Effective mechanisms of TAAs were confirmed as both of arresting cell cycle at G1 phase and inducing apoptosis dose- and time-dependently. Mitochondrial and recipient pathways involved in apoptotic actions of TAAs. CONCLUSION: TAAs is effective for hepatocarcinoma, via inhibiting proliferation and inducing apoptosis.

The promise of dried fruits in cancer chemoprevention.

Chemoprevention is an attempt to use nontoxic natural and synthetic substances or their mixtures to intervene the relatively early stages of carcinogenesis, before invasive characteristics are manifested. The consumption of fruits is well known to reduce the risk of human cancers. Although most fruits are available only on a seasonal basis, recent advances in food processing technologies have made it possible to extend the shelf life of fruits and fruit-products. Fruits can be preserved by applying different drying processes to reduce the moisture content. Different varieties of dried fruits are now sold in supermarkets, thereby making them readily accessible to consumers. Since oxidative stress and chronic inflammation play important roles in cancer development, dried fruits with antioxidative and anti-inflammatory properties hold promise for cancer chemoprevention. The antioxidant, anti-inflammatory and chemopreventive activities of dried fruits are largely attributed to their polyphenols and vitamins. Dried fruits contain adequate amounts of bioactive principles, such as anthocyanins, acetogenins, catechins, coumarins, phenolic acids, terpenes, xanthones, and others. Since numerous health beneficial phytochemicals in fruits are conserved even after processing, regular intake of dried fruits can help prevent cancer. This review addresses the chemopreventive potential of representative dried fruits and their active constituents.

Anti-tumor activity of Annona squamosa seeds extract containing annonaceous acetogenin compounds.

ETHNOPHARMACOLOGICAL RELEVANCE: Seeds of Annona squamosa L. have been used in the south of China as a folk remedy to treat "malignant sores" (cancer). AIM OF THE STUDY: To investigate the chemical constituents and the anti-tumor activity of the standardized A. squamosa seeds extract in vitro and in vivo. MATERIALS AND METHODS: Annonaceous acetogenin profiles of the standardized extract were determined by using Fourier transform infrared (FT-IR) and high performance liquid chromatography (HPLC) techniques. The anti-tumor activity of the extract was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cytotoxicity in vitro and H(22) hepatoma cells transplantation tumor model in vivo. RESULTS: The FT-IR spectroscopy showed the presence of annonaceous acetogenin compounds in the extract. Two major annonaceous acetogenins: 12, 15-cis-squamostatin-A and bullatacin were identified and quantified by HPLC. The seed extract showed significant anti-tumor activity against four human tumor cell lines, especially for MCF-7 (IC(50). 0.25 µg/ml) and Hep G2 (IC(50). 0.36 µg/ml) cells in vitro. The extract inhibited the growth of H(22) tumor cells in mice with a maximum inhibitory rate of 69.55% by oral administration. CONCLUSION: A. squamosa seed extract showed significant anti-tumor activities against human hepatoma cells in vitro and in vivo, indicating a potential for developing the extract as a novel anti-liver cancer drug.

Antitumor activity of annonaceous acetogenins in HepS and S180 xenografts bearing mice.

Annonaceous acetogenins (ACGs), as one of the most powerful groups of mitochondrial complex I inhibitors, exhibit potent cytotoxic activity against a variety of human tumor cell lines. In this study, the antitumor activities of three main types of ACGs were investigated using S180 and HepS xenografts bearing mice simultaneously. The results revealed that select ACGs suppressed tumor growth in a dose-dependent fashion. Tested ACGs showed more selective antitumor activity against HepS. Furthermore, adjacent bis-THF ACGs were more active than mono-THF and nonadjacent bis-THF ACGs against HepS and S180; nonadjacent bis-THF ACGs were more active than mono-THF ACGs against S180, but mono-THF ACGs were more potent than nonadjacent bis-THF ACGs against HepS.

Attenuation of experimental TPA-induced dermatitis by acetylenic acetogenins is associated with inhibition of PLA2 activity.

Topical application of acetylenic acetogenins (AAG) from avocado (0.01-1.0mg/ear), was effective in inhibiting both 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema, and in decreasing tissue myeloperoxidase activity (indicative of polymorphonuclear leukocyte influx). Maximum edema inhibition of 72% was achieved by AAG at lower concentration (0.6 mg/ear) than that of the anti-inflammatory drug indomethacin (2mg/ear). The maximum myeloperoxidase inhibition of 60% was obtained at AAG concentration 0.1mg/ear. Chemical reduction of unsaturated bonds in aliphatic chain of AAG molecules almost abrogated inhibition effect of AAG at high concentration. In vitro AAG administration reduced secretion of PGE(2) in TPA-induced keratinocytes, and inhibited total PLA(2) and sPLA(2) activities in HaCaT cells. The results indicate a topical anti-inflammatory effect of acetylenic acetogenins which is associated with inhibition of PLA(2) activity in skin.

Cytotoxic activity of acetogenins and styryl lactones isolated from Goniothalamus undulatus Ridl. root extracts against a lung cancer cell line (COR-L23).

An investigation of the chemical constituents in a dichloromethnae extract of Goniothalamus undulatus root led to the isolation of three known styryl lactones (5-acetoxyisogoniothalamin oxide, O-acetylaltholactone and altholactone), and four known annonaceous acetogenins (annonacin, cis-annonacin, goniothalamicin and cis-goniothalamicin). These compounds were subjected to a sulphorhodamine B (SRB) cytotoxicity assay against human large cell lung carcinoma (COR-L23), and normal human fetal fibroblast (MRC-5), cell lines. The isolated acetogenins showed higher cytotoxic activity against COR-L23 compared to the styryl lactones, with IC50 values in the range of 0.5-1.7 µM and 7.4-15.4 µM, respectively. A similar pattern of cytotoxicity was also observed against the other cell line (MRC-5); acetogenins IC50 values were in the range of 11.8-31.4 µM, and those for styryl lactones were in the range of 48.7-102.8 µM. This is the first report of a bioassay-guided isolation of chemical constituents from G. undulatus and on cytotoxic studies of the isolated compounds using these particular lung cancer cell lines.