Anti-apoptotic protein BCL-XL plays a vital role in tumorigenesis and cancer chemotherapy resistance, resulting in a good target for cancer treatment. Understanding the function of BCL-XL has driven the progression of a new class of cancer drugs that can mimic its natural inhibitors, BH3-only proteins, to trigger apoptosis. This mimicking is initiated through acetogenins due to their excellent biological properties. Acetogenins, which can be isolated from Annonaceae plants, have a unique structure along with several oxygenated functionalities. Objective: Based on their biological capability, various acetogenins were studied in the present study and compared alongside ABT-737 on molecular docking. Methods: The docking simulation of acetogenins was performed using AutoDock Vina software. Results: Our findings have shown eleven acetogenins-BCL-XL protein complex, namely, muricin B (2), muricin F (4), muricin H (6), muricin I (7), xylomaticin (9), annomontacin (12), annonacin (14), squamocin (15), squamostatin A (16), bullatacin (20) and annoreticulin (21) exhibited strong binding affinities lower than – 10.4 kcalmol-1 as compared to ABT-373-BCL-XL complex. Six hydrogen bonds along with hydrophobic interaction were detected on the complex of BCL-XL with muricin B (2), muricin G (5), corossolone (11), and isoannonacin-10-one A (18). Conclusion: These findings indicated that some acetogenins could represent a new potential BCLXL inhibitor that could mimic the BH3-only protein for the induction of apoptosis in cancer chemotherapy.

The investigation was to evaluate gastroprotective effects of ethanolic extract of M. pruriens leaves on ethanol-induced gastric mucosal injuries in rats. Forty-eight rats were divided into 8 groups: negative control, extract control, ulcer control, reference control, and four experimental groups. As a pretreatment, the negative control and the ulcer control groups were orally administered carboxymethylcellulose (CMC). The reference control was administered omeprazole orally (20?mg/kg). The ethanolic extract of M. pruriens leaves was given orally to the extract control group (500?mg/kg) and the experimental groups (62.5, 125, 250, and 500?mg/kg). After 1?h, CMC was given orally to the negative and the extract control groups. The other groups received absolute ethanol. The rats were sacrificed after 1?h. The ulcer control group exhibited significant mucosal injuries with decreased gastric wall mucus and severe damage to the gastric mucosa. The extract caused upregulation of Hsp70 protein, downregulation of Bax protein, and intense periodic acid schiff uptake of glandular portion of stomach. Gastric mucosal homogenate showed significant antioxidant properties with increase in synthesis of PGE2, while MDA was significantly decreased. The ethanolic extract of M. pruriens leaves was nontoxic (<5?g/kg) and could enhance defensive mechanisms against hemorrhagic mucosal lesions.

Therapy that directly targets apoptosis and/or inflammation could be highly effective for the treatment of cancer. Murraya koenigii is an edible herb that has been traditionally used for cancer treatment as well as inflammation. Here, we describe that girinimbine, a carbazole alkaloid isolated from M. koenigii, induced apoptosis and inhibited inflammation in vitro as well as in vivo. Induction of apoptosis in human colon cancer cells (HT-29) by girinimbine revealed decreased cell viability in HT-29, whereas there was no cytotoxic effect on normal colon cells. Changes in mitochondrial membrane potential, nuclear condensation, cell permeability, and cytochrome c translocation in girinimbine-treated HT-29 cells demonstrated involvement of mitochondria in apoptosis. Early-phase apoptosis was shown in both acridine orange/propidium iodide and annexin V results. Girinimbine treatment also resulted in an induction of G0/G1 phase arrest which was further corroborated with the upregulation of two cyclin-dependent kinase proteins, p21 and p27. Girinimbine treatment activated apoptosis through the intrinsic pathway by activation of caspases 3 and 9 as well as cleaved caspases 3 and 9 which ended by triggering the execution pathway. Moreover, apoptosis was confirmed by downregulation of Bcl-2 and upregulation of Bax in girinimbine-treated cells. In addition, the key tumor suppressor protein, p53, was seen to be considerably upregulated upon girinimbine treatment. Induction of apoptosis by girinimbine was also evidenced in vivo in zebrafish embryos, with results demonstrating significant distribution of apoptotic cells in embryos after a 24-hour treatment period. Meanwhile, anti-inflammatory action was evidenced by the significant dose-dependent girinimbine inhibition of nitric oxide production in lipopolysaccharide/interferon-gamma-induced cells along with significant inhibition of nuclear factor-kappa B translocation from the cytoplasm to nucleus in stimulated RAW 264.7 cells. Girinimbine was also shown to have considerable antioxidant activity whereby 20 ?g/mL of girinimbine was equivalent to 82.17±1.88 µM of Trolox. In mice with carrageenan-induced peritonitis, oral pretreatment with girinimbine helped limit total leukocyte migration (mainly of neutrophils), and reduced pro-inflammatory cytokine levels (interleukin-1beta and tumor necrosis factor-alpha) in the peritoneal fluid. These findings strongly suggest that girinimbine could act as a chemopreventive and/or chemotherapeutic agent by inducing apoptosis while suppressing inflammation. There is a potential for girinimbine to be further investigated for its applicability in treating early stages of cancer.

Biological activities of crude methanolic extracts from leaves, barks, twigs and roots ofEnicosanthellum pulchrum were investigated in four bioassays. The antioxidant, 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay showed that bark and twig extracts showed high inhibitory activity with 60 and 56% inhibition at 1 mglmL and IC50values of 0.43 t 0.04 and 0.64 t 0.05 mglmL, respectively. The bark and root extracts showed greater reducing power (FRAP) than several standard drugs used in the bioassay. Methanolic extracts of leaves, twigs and roots displayed strong cytotoxicity to breast cancer cell line (MCF-7), myelomonocytic leukaemia cell line (WEHI-3) and ovarian cancer cell line (CAOV-3); the IC50 of the leaf extract were 7.8 t 0.85 pg/mL (MCF-7) and 9.0 t 0.13 pgImL (WEHI-3), while those for the twig and root extracts were 13.9 t 0.35 and 7.3 t 0.98 pg/mL (CAOV-3), respectively. In the antimicrobial assays, the extracts were tested against ten bacterial strains and two fimgal strains. Bark and twig extracts displayed high inhibitory activity to Bacillus subtilis with 13.3 t 0.57 and 12.0 t 0.01 mm inhibition, respectively. In addition, the twig extract displayed better minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) compared with the bark extract (MIC 0.5 and 1.0 mg/mL, MBC 1.0 and 2.0 mg/mL, respectively). For antifitngal activity, all extracts showed inhibition on Candida albicans but not on Aspergillus niger. The obtained results suggested that this plant may possibly contain bioactive compounds in the active extracts.

The oxoaporphine alkaloid lysicamine (1), and three proaporphine alkaloids, litsericinone (2), 8,9,11,12-tetrahydromecambrine (3) and hexahydromecambrine A (4) were isolated from the leaves of Phoebe grandis (Nees) Merr. (Lauraceae). Compounds 2 and 3 were first time isolated as new naturally occurring compounds from plants. The NMR data for the compounds 2–4 have never been reported so far. Compounds 1 and 2 showed significant cytotoxic activity against a MCF7 (human estrogen receptor (ER+) positive breast cancer) cell line with IC50 values of 26 and 60 µg/mL, respectively. Furthermore, in vitro cytotoxic activity against HepG2 (human liver cancer) cell line was evaluated for compounds 1–4 with IC50 values of 27, 14, 81 and 20 µg/mL, respectively. Lysicamine (1) displayed strong antibacterial activity against Bacillus subtilis (B145), Staphylococcus aureus (S1434) and Staphylococus epidermidis (a clinically isolated strain) with inhibition zones of 15.50 ± 0.57, 13.33 ± 0.57 and 12.00 ± 0.00 mm, respectively. However, none of the tested pathogenic bacteria were susceptible towards compounds 2 and 3

Artonin E is a prenylated flavonoid isolated from the stem bark of Artocarpus elasticus Reinw.(Moraceae). This study aimed to investigate the apoptotic mechanisms induced by artonin E in a metastatic human ovarian cancer cell line SKOV-3 in vitro. MTT assay, clonogenic assay, acridine orange and propidium iodide double staining, cell cycle and annexin V analyses were performed to explore the mode of artonin E-induced cell death at different time points. DNA laddering, activation of caspases-3, -8, and -9, multi-parametric cytotoxicity-3analysis by high-content screening, measurement of reactive oxygen species generation, and Western blot were employed to study the pathways involved in the apoptosis. MTT results showed that artonin E inhibited the growth of SKOV-3 cells, with IC50 values of 6.5±0.5μg/mL after 72 h treatment, and showed less toxicity toward a normal human ovarian cell lineT1074, with IC50 value of 32.5±0.5μg/mL. Results showed that artonin E induced apoptosis and cell cycle arrest at the S phase. This compound also promoted the activation of caspases-3, -8, and -9. Further investigation into the depletion of mitochondrial membrane potential and release of cytochrome c revealed that artonin E treatment induced apoptosis via regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. The expression levels of survivin and HSP70 proteins were also down regulated in SKOV-3 cells treated with artonin E. We propose that artonin E induced an antiproliferative effect that led to S phase cell cycle arrest and apoptosis through dysregulation of mitochondrial pathways, particularly the pro- and anti-apoptosis signaling pathways.

Two new limonoids, chisomicines D and E (1 - 2) have been isolated from the bark of Malaysian Chisocheton ceramicus (Miq.) C. DC. Their structures were elucidated on the basis of 1D and 2D-NMR data analysis.

Background: Cleistopholine is a natural alkaloid present in plants with numerous biological activities. However, cleistopholine has yet to be isolated using modern techniques and the mechanism by which this alkaloid induces apoptosis in cancer cells remains to be elucidated. Hypothesis/purpose: This study aims to isolate cleistopholine from the roots of Enicosanthellum pulchrum by using preparative-HPLC technique and explore the mechanism by which this alkaloid induces apoptosis in human ovarian cancer (CAOV-3) cells in vitro from 24 to 72 h. This compound may be developed as an anticancer agent that induces apoptosis in ovarian cancer cells. Study design/methods: Cytotoxicity was assessed via the cell viability assay and changes in cell morphology were observed via the acridine orange/propidium iodide (AO/PI) assay. The involvement of apoptotic pathways was evaluated through caspase analysis and multiple cytotoxicity assays. Meanwhile, early and late apoptotic events via the Annexin V-FITC and DNA laddering assays, respectively. The mechanism of apoptosis was explored at the molecular level by evaluating the expression of specific genes and proteins. In addition, the proliferation of CAOV-3-cells treated with cleistopholine was analysed using the cell cycle arrest assay. Results: The IC50 of cleistopholine (61.4 µM) was comparable with that of the positive control cisplatin (62.8 µM) at 24 h of treatment. Apoptos is was evidenced by cell membrane blebbing, chromatin compression and formation of apoptotic bodies. The initial phase of apoptosis was detected at 24 h by the increase in Annexin V-FITC binding to cell membranes. A DNA ladder was formed at 48 h, indicating DNA fragmentation in the final phase of apoptosis. The mitochondria participated in the process by stimulating the intrinsic pathway via caspase 9 with a reduction in mitochondrial membrane potential (MMP) and an increase in cytochrome c release. Cell death was further validated through the mRNA and protein overexpression of Bax, caspase 3 and caspase 9 in the treated cells compared with the untreated cells. In contrast, Bcl-2, Hsp70 and survivin decreased in expression upon cleistopholine treatment. Cell cycle was arrested at the G0/G1 phase and cell population percentage significantly increased to 43.5%, 45.4% and 54.3% in time-dependent manner in the cleistopholine-treated CAOV-3 cells compared with the untreated cells at 24, 48 and 72 h respectively. Conclusion: The current study indicated that cleistopholine can be a potential candidate as a new drug to treat ovarian cancer disease.

The emergence of new drug discovery for cancer treatment is vital and continuously gaining global attention. Although the discovery and development of a new drug takes a long time, the efforts should be retained. Successful findings could be repeated for cancer therapy from natural compounds by investigating flavonoids from molecular docking as the initial study towards the drug development process. Flavonoids derived from plants are believed to have the capability to interact with cancer-related proteins. The present study aims to identify the most favourable cancer-related proteins to be targeted by selected flavonoids through molecular docking simulation. In this study, selected flavonoids from different classes have been docked with several targeted proteins which are involved in cell death, survival, and proliferation, such as death receptors 4 and 5 (DR4 and DR5), epidermal growth factor receptor (EGFR) and farnesyltransferase (FTase). Of all the proteins tested for docking simulation, EGFR protein is among the best-targeted proteins compared to other proteins with the lowest binding energies for each flavonoid, ranging from -9.1 to -8.4 kcalmol-1. Meanwhile, myricetin (7) exhibited the strongest binding affinity for three proteins, including EGFR, FTase and DR5. On the other hand, DR4 protein has shown interaction favourably with flavone (5) with the binding affinity of -8.0 kcalmol-1. The docking results suggest that the selected flavonoids generally have good binding affinities and interactions with cancer-target proteins, which could be proposed as inhibitors of targeted-proteins in cancer therapy.

The platelet-activating factor receptor (PAFR) has been a therapeutic target for platelet- activating factor (PAF)-mediated diseases. The pathophysiological condition is triggered by the interaction of PAF agonist. The discovery of PAF antagonists from natural flavonoids could be promising candidates for treating PAF-mediated diseases. Flavonoids that exist in most edible plants possess good health benefits to the human body. The study aimed to investigate the ability of three flavonoids (apigenin, galangin and fisetin) for molecular docking and dynamic simulations into PAFR protein. The PAFR-flavonoid complex binding affinities and interactions were assessed through molecular docking and dynamic simulations. Results found that all flavonoids significantly have a good binding affinity, ranging from - 9.1 to - 8.9 kcalmol-1. The stability of these flavonoids was also achieved in a 30 ns simulation. Four critical residues were detected in all PAFR-flavonoids complexes (Phe97, Phe98, Thr101 and Leu279) from the analysis of MMGBSA binding free energy. Interactions of van der Waals and electrostatic were seen by individual key residues of PAFR for the free energy contribution of ligands binding. All flavonoids showed promising anti-PAF candidate to be developed in the future.

Enicosanthellum pulchrum is a tropical plant from Malaysia and belongs to the Annonaceae family. This plant is rich in isoquinoline alkaloids. In the present study, liriodenine, an isoquinoline alkaloid, was examined as a potential anticancer agent, particularly in ovarian cancer. Liriodenine was isolated by preparative high-performance liquid chromatography. Cell viability was performed to determine the cytotoxicity, whilst the detection of morphological changes was carried out by acridine orange/propidium iodide assay. Initial and late apoptosis was examined by Annexin V-fluorescein isothiocyanate and DNA laddering assays, respectively. The involvement of pathways was detected via caspase-3, caspase-8, and caspase-9 analyses. Confirmation of pathways was further performed in mitochondria using a cytotoxicity 3 assay. Apoptosis was confirmed at the protein level, including Bax, Bcl-2, and survivin, while interruption of the cell cycle was used for final validation of apoptosis. The result showed that liriodenine inhibits proliferation of CAOV-3 cells at 37.3 µM after 24 hours of exposure. Changes in cell morphology were detected by the presence of cell membrane blebbing, chromatin condensation, and formation of apoptotic bodies. Early apoptosis was observed by Annexin V-fluorescein isothiocyanate bound to the cell membrane as early as 24 hours. Liriodenine activated the intrinsic pathway by induction of caspase-3 and caspase-9. Involvement of the intrinsic pathway in the mitochondria could be seen, with a significant increase in mitochondrial permeability and cytochrome c release, whereas the mitochondrial membrane potential was decreased. DNA fragmentation occurred at 72 hours upon exposure to liriodenine. The presence of DNA fragmentation indicates the CAOV-3 cells undergo late apoptosis or final stage of apoptosis. Confirmation of apoptosis at the protein level showed overexpression of Bax and suppression of Bcl-2 and survivin. Liriodenine inhibits progression of the CAOV-3 cell cycle in S phase. These findings indicate that liriodenine could be considered as a promising anticancer agent.

Actinodaphne sesquipedalis Hook. F. Var. Glabra (Kochummen), also known as "Medang payung" by the Malay people, belongs to the Lauraceae family. In this study, methanol leaf extract of A. sesquipedalis was investigated for their acute toxicity and gastroprotective effects to reduce ulcers in rat stomachs induced by ethanol. The rats were assigned to one of five groups: normal group (group 1), ulcer group (group 2), control positive drug group (group 3) and two experimental groups treated with 150 mg/kg (group 4) and 300 mg/kg (group 5) of leaf extract. The rats were sacrificed an hour after pretreatment with extracts, and their stomach homogenates and tissues were collected for further evaluation. Macroscopic and histological analyses showed that gastric ulcers in rats pretreated with the extract were significantly reduced to an extent that it allowed leukocytes penetration of the gastric walls compared with the ulcer group. In addition, an ulcer inhibition rate of >70% was detected in rats treated with both doses of A. sesquipedalis extract, showing a notable protection of gastric layer. Severe destruction of gastric mucosa was prevented with a high production of mucus and pH gastric contents in both omeprazole-treated and extract-treated groups. Meanwhile, an increase in glycoprotein uptake was observed in pretreated rats through accumulation of magenta color in Periodic Acid Schiff staining assay. Analysis of gastric homogenate from pretreated rats showed a reduction of malondialdehyde and elevation of nitric oxide, glutathione, prostaglandin E2, superoxide dismutase and protein concentration levels in comparison with group 2. Suppression of apoptosis in gastric tissues by upregulation of Hsp70 protein and downregulation of Bax protein was also observed in rats pretreated with extract. Consistent results of a reduction of gastric ulcer and the protection of gastric wall were obtained for rats pretreated with A. sesquipedalis extract, which showed its prominent gastroprotective potential in rats' stomach against ethanol-induced ulcer.

Background: The anti-apoptotic protein Bcl-xL is a viable target for cancer therapy due to its critical role in cancer formation and resistance to chemotherapy. Insights into Bcl-xL’s role have spurred the development of a new category of cancer drugs called Bcl-xL inhibitors, which mimic the BH3-only protein to cause apoptosis. It could be initiated using alkaloids, owing to their remarkable biological characteristics. Alkaloids, among the biggest obtainable from plants, possess a distinctive structure characterized by the presence of a nitrogen atom in various positions within the molecule. Objective: In the current study, the potential of various alkaloids as Bcl-xL inhibitors was investigated through a molecular docking study. Methods: AutoDock Vina software was used to perform docking simulations of the alkaloids. Results: Ten alkaloids/Bcl-xL protein complexes demonstrated strong binding affinities less than -8.0 kcal/mol-1. These complexes include phaenthine (26), 4,5-Dioxoaporphine (1), anonaine (2), atherospermidine (4), limacine (14), liriodenine (16), monomargine (18), ouregidione (24), oxostephanine (25), and taliscanine (29) as the ligand of Bcl-xL protein. Notably, the complexes of Bcl-xL/dicentrinone (10), ouregidione (24), stepharine (28), and taliscanine (29) displayed three to four hydrogen bonds along with hydrophobic contacts. Conclusion: These results suggest that certain alkaloids could act as potential Bcl-xL inhibitors, mimicking BH3-only proteins and thereby potentially triggering apoptosis during cancer treatment

Background: Platelet-activating factor (PAF) is an agonist mediator in the inflammatory process, which interacts with PAF receptor (PAFR) that eventually causes cancers, respiratory and neurodegenerative diseases. This interaction activates the mitogen-activated protein kinase (MAPK) pathway, leading to a pro-inflammatory cascade. The pathophysiological conditions due to activation of inflammatory cascade could be inhibited by PAF antagonists. Objectives: In this study, selected naturally derived flavonoids (flavone, biochanin A, and myricetin) with different functional groups were subjected to molecular modelling and experimental studies to investigate their potential as PAF antagonists. Methods: Interactions of flavonoids and PAF were assessed via Autodock Vina for molecular docking and the AMBER program for molecular dynamic simulations. The experimentally antagonistic effects of the flavonoids were also conducted via PAF inhibitory assay to determine the IC50 values. Results: The findings of docking and dynamic simulations have revealed that all selected flavonoids interact with PAFR in the binding site with considerably good binding affinity up to - 9.8 kcal mol-1 as compared to cedrol (- 8.1 kcal mol-1) as a standard natural PAFR antagonist. The PAFR-flavonoid complexes exhibited four conserved active site residues, which included W73, F97, F174, and L279. The stability of all complexes was attained in a 30 ns simulation. The findings of in silico analyses were then compared to the experimental study on PAF inhibitory assay. Inhibitory effects of flavonoids against PAFR showed moderate activities, ranging from 27.8 – 30.8 μgM-1. Conclusion: All studied flavonoids could act as promising PAF antagonists with some enhancement in their structures to exhibit potent antagonistic activity. However, these naturally derived flavonoids demand further investigation at cellular and animal models to develop new PAF antagonist drug candidates for treating PAF-mediated diseases.

Pseuduvarines A (1) and B (2), two new dioxoaporphine alkaloids with an amino moiety, were isolated from the stem bark of Pseuduvaria rugosa and their structures were elucidated by combination of 2D-NMR spectroscopic analysis. Pseuduvarines A (1) and B (2) showed cytotoxicity against MCF7, HepG2, and HL-60 (1: IC50, 0.9, 21.7, and >50.0 μM, respectively, 2: IC50 >50.0, 15.7, and 12.4 μM, respectively).

Drug resistance presents a challenge in chemotherapy and has attracted research interest worldwide and particular attention has been given to natural compounds to overcome this difficulty. Pulchrin A, a new compound isolated from natural products has demonstrated novel potential for development as a drug. The identification of pulchrin A was conducted using several spectroscopic techniques such as nuclear magnetic resonance, liquid chromatography mass spectrometer, infrared and ultraviolet spectrometry. The cytotoxicity effects on CAOV-3 cells indicates that pulchrin A is more active than cisplatin, which has an IC50 of 22.3 ?M. Significant changes in cell morphology were present, such as cell membrane blebbing and formation of apoptotic bodies. The involvement of phosphatidylserine (PS) in apoptosis was confirmed by Annexin V-FITC after a 24 h treatment. Apoptosis was activated through the intrinsic pathway by activation of procaspases 3 and 9 as well as cleaved caspases 3 and 9 and ended at the executioner pathway, with the occurrence of DNA laddering. Apoptosis was further confirmed via gene and protein expression levels, in which Bcl-2 protein was down-regulated and Bax protein was up-regulated. Furthermore, the CAOV-3 cell cycle was disrupted at the G0/G1 phase, leading to apoptosis. Molecular modeling of Bcl-2 proteins demonstrated a high- binding affinity, which inhibited the function of Bcl-2 proteins and led to cell death. Results of the current study can shed light on the development of new therapeutic agents, particularly, human ovarian cancer treatments.