Natural Compounds with BMI1 Promoter Inhibitory Activity from Mammea siamensis and Andrographis paniculata.

A new coumarin derivative (1) and 30 known compounds were isolated from Mammea siamensis and Andrographis paniculata, guided by B cell-specific Moloney murine leukemia virus insertion region 1 (BMI1) promoter inhibitory activity. Among the isolated compounds, 15 compounds showed BMI1 promoter inhibitory activity, and five compounds were found to be cytotoxic. 14-Deoxy-11,12-dehydroandrographolide (18) was highly cytotoxic to DU145 cells with an IC50 value of 25.4 µM. Western blotting analysis of compound 18 in DU145 cells suggested that compound 18 suppresses BMI1 expression.

A Review on Mechanistic Insight of Plant Derived Anticancer Bioactive Phytocompounds and Their Structure Activity Relationship.

Cancer is a disorder that rigorously affects the human population worldwide. There is a steady demand for new remedies to both treat and prevent this life-threatening sickness due to toxicities, drug resistance and therapeutic failures in current conventional therapies. Researchers around the world are drawing their attention towards compounds of natural origin. For decades, human beings have been using the flora of the world as a source of cancer chemotherapeutic agents. Currently, clinically approved anticancer compounds are vincristine, vinblastine, taxanes, and podophyllotoxin, all of which come from natural sources. With the triumph of these compounds that have been developed into staple drug products for most cancer therapies, new technologies are now appearing to search for novel biomolecules with anticancer activities. Ellipticine, camptothecin, combretastatin, curcumin, homoharringtonine and others are plant derived bioactive phytocompounds with potential anticancer properties. Researchers have improved the field further through the use of advanced analytical chemistry and computational tools of analysis. The investigation of new strategies for administration such as nanotechnology may enable the development of the phytocompounds as drug products. These technologies have enhanced the anticancer potential of plant-derived drugs with the aim of site-directed drug delivery, enhanced bioavailability, and reduced toxicity. This review discusses mechanistic insights into anticancer compounds of natural origins and their structural activity relationships that make them targets for anticancer treatments.

Opportunities and challenges in stem cell therapy in cardiovascular diseases: Position standing in 2022.

This study intends to evaluate the development, importance, pre-clinical and clinical study evaluation of stem cell therapy for the treatment of cardiovascular disease. Cardiovascular disease is one of the main causes of fatality in the whole world. Though there are great progressions in the pharmacological and other interventional treatment options, heart diseases remain a common disorder that causes long-term warnings. Recent accession promotes the symptoms and slows down the adverse effects regarding cardiac remodelling. But they cannot locate the problems of immutable loss of cardiac tissues. In this case, stem cell treatment holds a promising challenge. Stem cells are the cells that are capable of differentiating into many cells according to their needs. So, it is assumed that these cells can distinguish into many cells and if these cells can be individualized into cardiac cells then they can be used to replace the damaged tissues of the heart. There is some abridgment in this therapy, none the less stem cell therapy remains a hopeful destination in the treatment of heart disease.

Two new coumarins and a new xanthone from the leaves of Rhizophora mucronata.

Two new coumarins (1, 2) and a new xanthone (3), together with 14 known compounds-eight coumarins (4, 5, 9, 10, 12-15), three xanthones (11, 16, 17), a benzoic acid (6) and two flavonones (7, 8)-were isolated from the leaves of Rhizophora mucronata. The structures of the compounds were elucidated by spectroscopic (IR, MS, and NMR) analyses. The isolated compounds were tested for cytotoxicity against human cancer cell lines HL-60 and HeLa. Among these compounds, only compound 16 inhibited the growth of both HeLa (IC50 = 4.8 µM) and HL-60 (IC50 = 1.0 µM) cells. Compounds 4, 7, 10, and 12 exhibited moderate activity against HeLa cells (IC50 = 3.8-8.3 µM). Compounds 5, 9, 11, and 17 showed moderate activity against HL-60 cells (IC50 = 2.2-6.3 µM). Higher selectivity against HL-60 cell lines was observed for compounds 5, 9, 11, and 16 with SI values (NIH 3T3/HL-60) of 8.6, 19.2, 9.4, and 10.2, respectively.

Hes1-Binding Compounds Isolated by Target Protein Oriented Natural Products Isolation (TPO-NAPI).

Hairy and enhancer of split 1 (Hes1) is a transcription factor that acts in neural stem cells to inhibit differentiation. We recently developed target protein oriented natural products isolation (TPO-NAPI) using Hes1-immobilized beads to identify activators of neural stem cells. Isomicromonolactam (1), staurosporin (2), and linarin (3) were isolated as Hes1-binding compounds using the TPO-NAPI method. Of these, compound 1 enhanced neural stem cell differentiation. Using truncated Hes1 proteins, the binding region of Hes1 for 1 was estimated to be in the C-terminal half that includes a TLE/Grg binding site. The differentiation-promoting activity of inohanamine (4) is also reported.

Notch Inhibitors from Calotropis gigantea That Induce Neuronal Differentiation of Neural Stem Cells.

Neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease occur due to loss of the structure and function of neurons. For the potential treatment of neurodegenerative diseases, accelerators of neuronal differentiation of neural stem cells (NSCs) have been focused on and a cell-based assay system for measuring Notch signaling pathway activity was constructed. Using this assay system, eight compounds isolated from Calotropis gigantea were identified as inhibitors of the Notch signaling pathway. Hes1 and Hes5 are target genes of the Notch signaling pathway, and compound 1, called uscharin, decreased the protein levels of Hes1 and Hes5 in assay cells and MEB5 cells (mouse NSCs). Furthermore, uscharin (1) enhanced the differentiation of MEB5 cells into neurons. The mechanism of uscharin (1) for the Notch signaling inhibitory activity would be acceleration of the degradation of the Notch intracellular domain (NICD) in the MEB5 cells.

Boesenberols, Pimarane Diterpenes with TRAIL-Resistance-Overcoming Activity from Boesenbergia pandurata.

TRAIL is a potent and selective inducer of apoptosis in most cancer cells while sparing normal cells, which makes it an attractive target for the development of new cancer therapies. In a screening program on natural resources with the ability to abrogate TRAIL resistance, the bioassay-guided fractionation of Boesenbergia pandurata rhizomes resulted in the isolation of 17 pimarane diterpenes and a monoterpene. Among these, compounds 1-8, named boesenberols A-H, are new pimarane diterpenes. All compounds exhibited TRAIL-resistance-overcoming activity in TRAIL-resistant AGS cells. Subtoxic doses of the major compound 9 sensitized AGS cells to TRAIL-induced apoptosis by up-regulating apoptosis-inducing proteins, such as DR4, DR5, p53, Fas, CHOP, Bak, and cleaved caspases-3, -8, and -9, and down-regulating the levels of cell survival proteins, such as Bcl-2, c-FLIP, and GSK-3ß, in TRAIL-resistant AGS cells. Furthermore, compound 9 did not decrease the viability of noncancerous (HEK293) cells at concentrations up to 30 µM.

Bio-active Natural Products with TRAIL-Resistance Overcoming Activity.

Tumor necrosis factor related apoptosis-inducing ligand (TRAIL) has emerged as a promising anticancer agent as it selectively kills cancer cells. However, TRAIL resistance limits its use as a therapeutic agent. An understanding the mechanisms responsible for TRAIL resistance and strategies to overcome it are important for its effective use as an anticancer agent. During our studies to screen natural products from medicinal plants, we identified a number of compounds with synergistic effects on TRAIL-induced apoptosis in tumor cells. This review describes our recent studies on the isolation of bioactive compounds with TRAIL-resistance overcoming activity.

Hedgehog inhibitors from Withania somnifera.

The hedgehog (Hh) signaling pathway performs an important role in embryonic development and in cellular proliferation and differentiation. However, aberrant activation of the Hh signaling pathway is associated with tumorigenesis. Hh signal inhibition was evaluated using a cell-based assay system that targets GLI1-mediated transcription. Activity-guided isolation of the Withania somnifera MeOH extract led to the isolation of six compounds: withaferin A (1) and its derivatives (2-6). Compounds 1 and 2 showed strong inhibition of Hh/GLI1-mediated transcriptional activity with IC50 values of 0.5 and 0.6 µM, respectively. Compounds 1, 2, 3, and 6 were cytotoxic toward human pancreatic (PANC-1), prostate (DU145) and breast (MCF7) cancer cells. Furthermore, 1 also inhibited GLI1-DNA complex formation in EMSA.

Coronaridine, an iboga type alkaloid from Tabernaemontana divaricata, inhibits the Wnt signaling pathway by decreasing ß-catenin mRNA expression.

Four alkaloids, voacangine (1), isovoacangine (2), coronaridine (3), and coronaridine hydroxyindolenine (4), were isolated from the MeOH extract of Tabernaemontana divaricata aerial parts by activity-guided fractionation for Wnt signal inhibitory activity. Compounds 1-4 exhibited TCF/ß-catenin inhibitory activities with IC50 values of 11.5, 6.0, 5.8, and 7.3 µM, respectively. Of these, coronaridine (3) decreased ß-catenin levels in SW480 colon cancer cells, while this decrease in ß-catenin was not suppressed by a co-treatment with 3 and MG132, a proteasome inhibitor. These results suggested that the decrease observed in ß-catenin levels by coronaridine (3) did not depend on a proteasomal degradation process. On the other hand, the treatment of SW480 cells with coronaridine (3) caused a decrease in ß-catenin mRNA levels. Thus, coronaridine (3) may inhibit the Wnt signaling pathway by decreasing the mRNA expression of ß-catenin.

Boehmenan, a lignan from Hibiscus ficulneus, showed Wnt signal inhibitory activity.

The Wnt signal pathway modulates numerous biological processes, and its aberrant activation is related to various diseases. Therefore, inhibition of the Wnt signal may provide an effective (or efficient) strategy for these diseases. Cell-based luciferase assay targeting the Wnt signal (TOP assay) revealed that Hibiscus ficulneus extract inhibited the Wnt signal. The activity-guided isolation of the MeOH extract of H. ficulneus stems yielded four known (1-4) lignans along with myriceric acid (5). Compounds 1-4 potently inhibited the Wnt signal with TOPflash IC50 values of 1.0, 4.5, 6.3, and 1.9 µM, respectively. Compound 1 exhibited cytotoxicity against both Wnt-dependent (HCT116) and Wnt-independent (RKO) cells. Western blot analysis showed that 1 decreased the expression of full, cytosolic and nuclear ß-catenin along with c-myc in STF/293 cells. Our results suggested that 1 may have inhibited the Wnt signal by decreasing ß-catenin levels.

Hedgehog inhibitors from Artocarpus communis and Hyptis suaveolens.

The hedgehog (Hh) signaling pathway plays crucial roles in cell maintenance and proliferation during embryonic development. Naturally occurring Hh inhibitors were isolated from Artocarpus communis and Hyptis suaveolens using our previously constructed cell-based assay system. Bioactivity guided fractionation led to the isolation of 15 compounds, including seven new compounds (4, 5, 6, 7, and 9-11). The isolated compounds showed cytotoxicity against a cancer cell line (PANC1) in which Hh signaling was abnormally activated. Several compounds (12-14; GLI1 transcriptional inhibition IC50=7.6, 4.7, and 4.0 µM, respectively) inhibited Hh related protein (BCL2) expression. Moreover, compounds 1, 12, and 13 disrupted GLI1 and DNA complex formation.

Sesquiterpenes with TRAIL-resistance overcoming activity from Xanthium strumarium.

The ability of TRAIL to selectively induce apoptosis in cancer cells while sparing normal cells makes it an attractive target for the development of new cancer therapy. In search of bioactive natural products for overcoming TRAIL-resistance from natural resources, we previously reported a number of active compounds. In our screening program on natural resources targeting overcoming TRAIL-resistance, activity-guided fractionations of the extract of Xanthium strumarium led to the isolation of five sesquiterpene compounds (1-5). 11α,13-dihydroxanthinin (2) and 11α,13-dihydroxanthuminol (3) were first isolated from natural resources and xanthinosin (1), desacetylxanthanol (4), and lasidiol p-methoxybenzoate (5) were known compounds. All compounds (1-5) showed potent TRAIL-resistance overcoming activity at 8, 20, 20, 16, and 16 µM, respectively, in TRAIL-resistant AGS cells. Compounds 1 and 5 enhanced the levels of apoptosis inducing proteins DR4, DR5, p53, CHOP, Bax, cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9 and also decreased the levels of cell survival protein Bcl-2 in TRAIL-resistant AGS cells in a dose-dependent manner. Compound 1 also enhanced the levels of DR4 and DR5 proteins in a time-dependent manner. Thus, compounds 1 and 5 were found to induce both extrinsic and intrinsic apoptotic cell death. Compound 1 also exhibit TRAIL-resistance overcoming activity in DLD1, DU145, HeLa, and MCF7 cells but did not decrease viability in non-cancer HEK293 cells up to 8 µM.

Scopadulciol, Isolated from Scoparia dulcis, Induces ß-Catenin Degradation and Overcomes Tumor Necrosis Factor-Related Apoptosis Ligand Resistance in AGS Human Gastric Adenocarcinoma Cells.

Scopadulciol (1), a scopadulan-type diterpenoid, was isolated from Scoparia dulcis along with three other compounds (2-4) by an activity-guided approach using the TCF reporter (TOP) luciferase-based assay system. A fluorometric microculture cytotoxicity assay (FMCA) revealed that compound 1 was cytotoxic to AGS human gastric adenocarcinoma cells. The treatment of AGS cells with 1 decreased ß-catenin levels and also inhibited its nuclear localization. The pretreatment of AGS cells with a proteasome inhibitor, either MG132 or epoxomicin, protected against the degradation of ß-catenin induced by 1. The 1-induced degradation of ß-catenin was also abrogated in the presence of pifithrin-α, an inhibitor of p53 transcriptional activity. Compound 1 inhibited TOP activity in AGS cells and downregulated the protein levels of cyclin D1, c-myc, and survivin. Compound 1 also sensitized AGS cells to tumor necrosis factor-related apoptosis ligand (TRAIL)-induced apoptosis by increasing the levels of the death receptors, DR4 and DR5, and decreasing the level of the antiapoptotic protein Bcl-2. Collectively, our results demonstrated that 1 induced the p53- and proteasome-dependent degradation of ß-catenin, which resulted in the inhibition of TCF/ß-catenin transcription in AGS cells. Furthermore, 1 enhanced apoptosis in TRAIL-resistant AGS when combined with TRAIL.

Calotropin: a cardenolide from calotropis gigantea that inhibits Wnt signaling by increasing casein kinase 1α in colon cancer cells.

Wnt signaling plays key roles in embryonic development and various human diseases. Activity-guided testing to isolate Wnt signaling inhibitors from the methanol extract of Calotropis gigantea (Asclepiadaceae) exudutes identified six Wnt inhibitory cardenolides (1-6), of which 1, 3, 5, and 6 exhibited potent TCF/ß-catenin inhibitory activities (IC50 0.7-3.6 nM). Calotropin (1) inhibited Wnt signaling by decreasing both nuclear and cytosolic ß-catenin in a dose-dependent manner, and promoted degradation of ß-catenin by increasing the phosphorylation of ß-catenin at Ser45 through casein kinase 1α (CK1α). Moreover, 1 significantly increased CK1α protein and mRNA levels. The results suggest that 1 inhibits the Wnt signaling pathway by increasing CK1α protein levels. To the best of our knowledge, calotropin is the first small molecule to increase CK1α levels.

Ricinine: a pyridone alkaloid from Ricinus communis that activates the Wnt signaling pathway through casein kinase 1α.

Wnt signaling plays important roles in proliferation, differentiation, development of cells, and various diseases. Activity-guided fractionation of the MeOH extract of the Ricinus communis stem led to the isolation of four compounds (1-4). The TCF/ß-catenin transcription activities of 1 and 3 were 2.2 and 2.5 fold higher at 20 and 30µM, respectively. Cells treated with ricinine (1) had higher ß-catenin and lower of p-ß-catenin (ser 33, 37, 45, Thr 41) protein levels, whereas glycogen synthase kinase 3ß (GSK3ß) and casein kinase 1α (CK1α) protein levels remained unchanged. Cells treated with pyrvinium, an activator of CK1α, had lower ß-catenin levels. However, the combined treatment of pyrvinium and 1 led to higher ß-catenin levels than those in cells treated with pyrvinium alone, which suggested that 1 inhibited CK1α activity. Furthermore, 1 increased ß-catenin protein levels in zebrafish embryos. These results indicated that 1 activated the Wnt signaling pathway by inhibiting CK1α.

Physalin H from Solanum nigrum as an Hh signaling inhibitor blocks GLI1-DNA-complex formation.

Hedgehog (Hh) signaling plays an important role in embryonic development, cell maintenance and cell proliferation. Moreover, Hh signaling contributes to the growth of cancer cells. Physalins are highly oxidized natural products with a complex structure. Physalins (1-7) were isolated from Solanum nigrum (Solanaceae) collected in Bangladesh by using our cell-based assay. The isolated physalins included the previously reported Hh inhibitors 5 and 6. Compounds 1 and 4 showed strong inhibition of GLI1 transcriptional activity, and exhibited cytotoxicity against cancer cell lines with an aberrant activation of Hh signaling. Compound 1 inhibited the production of the Hh-related proteins patched (PTCH) and BCL2. Analysis of the structures of different physalins showed that the left part of the physalins was important for Hh inhibitory activity. Interestingly, physalin H (1) disrupted GLI1 binding to its DNA binding domain, while the weak inhibitor physalin G (2) did not show inhibition of GLI1-DNA complex formation.

Flavonoids: A treasure house of prospective pharmacological potentials.

Flavonoids are organic compounds characterized by a range of phenolic structures, which are abundantly present in various natural sources such as fruits, vegetables, cereals, bark, roots, stems, flowers, tea, and wine. The health advantages of these natural substances are renowned, and initiatives are being taken to extract the flavonoids. Apigenin, galangin, hesperetin, kaempferol, myricetin, naringenin, and quercetin are the seven most common compounds belonging to this class. A thorough analysis of bibliographic records from reliable sources including Google Scholar, Web of Science, PubMed, ScienceDirect, MEDLINE, and others was done to learn more about the biological activities of these flavonoids. These flavonoids appear to have promising anti-diabetic, anti-inflammatory, antibacterial, antioxidant, antiviral, cytotoxic, and lipid-lowering activities, according to evidence from in vitro, in vivo, and clinical research. The review contains recent trends, therapeutical interventions, and futuristic aspects of flavonoids to treat several diseases like diabetes, inflammation, bacterial and viral infections, cancers, and cardiovascular diseases. However, this manuscript should be handy in future drug discovery. Despite these encouraging findings, a notable gap exists in clinical research, hindering a comprehensive understanding of the effects of flavonoids at both high and low concentrations on human health. Future investigations should prioritize exploring bioavailability, given the potential for high inter-individual variation. As a starting point for further study on these flavonoids, this review paper may promote identifying and creating innovative therapeutic uses.

Isolation of bioactive phytochemicals from Crinum asiaticum L. along with their cytotoxic and TRAIL-resistance abrogating prospect assessment.

Crinum asiaticum L. (Amaryllidaceae) is a perennial bulbous herb, locally utilized for possessing multifaceted pharmacological properties including anticancer, immune-stimulating, analgesic, antiviral, antimalarial, antibacterial and antifungal, in addition to its popularity as an aesthetic plant. Separation of MeOH extract of C. asiaticum leaves yielded three known compounds as cycloneolitsol (1), hippeastrine (2) and ß-sitosterol (3). Among these, compounds 1 and 2 were subjected to the cytotoxic assay and found that they induced mild effect against HCT116, Huh7 and DU145 cell lines with the IC50 values from 73.76 to 132.53 µM. When tested for TRAIL-resistance abrogating activity, 1 (100 µM) along with TRAIL (100 ng/mL) showed moderate activity in AGS cells producing 25 % more inhibition than the agent alone. Whereas 2 (20 and 30 µM) in combination with TRAIL (100 ng/mL) exhibited strong activity in abrogating TRAIL-resistance and caused 34 % and 36 % more inhibition in AGS cells, respectively. The in-silico studies of compound 2 revealed high docking hits with the TRAIL-associated anti-apoptotic proteins which give a justification for the regulatory interactions to induce such abrogating activity. It is still recommended to conduct further investigations to understand their exact molecular mechanism.

Eudesmane-type sesquiterpenoid and guaianolides from Kandelia candel in a screening program for compounds to overcome TRAIL resistance.

In a screening program for natural products that can overcome TRAIL resistance, a new eudesmane-type sesquiterpenoid (1), three new guaianolides, mehirugins A-C (2-4), and two known guaianolides (5 and 6) were isolated from a MeOH extract of Kandelia candel leaves. Compounds 1 and 3-6 in combination with TRAIL showed cytotoxic activity in sensitizing TRAIL-resistant human gastric adenocarcinoma cells.