Metabolite Profile and In Vitro Beneficial Effects of Black Garlic (Allium sativum L.) Polar Extract.

Over the centuries, humans have traditionally used garlic (Allium sativum L.) as a food ingredient (spice) and remedy for many diseases. To confirm this, many extensive studies recognized the therapeutic effects of garlic bulbs. More recently, black garlic (BG), made by heat-ageing white garlic bulbs, has increased its popularity in cuisine and traditional medicine around the world, but there is still limited information on its composition and potential beneficial effects. In this study, the metabolite profile of methanol extract of BG (BGE) was determined by high-performance liquid chromatography coupled to tandem mass spectrometry in high-resolution mode. Results allowed to establish that BGE major components were sulfur derivatives, saccharides, peptides, organic acids, a phenylpropanoid derivative, saponins, and compounds typical of glycerophospholipid metabolism. Characterization of the BGE action in cancer cells revealed that antioxidant, metabolic, and hepatoprotective effects occur upon treatment as well as induction of maturation of acute myeloid leukemia cells. These results are interesting from the impact point of view of BG consumption as a functional food for potential prevention of metabolic and tumor diseases.

Antiviral Activity of Vitis vinifera Leaf Extract against SARS-CoV-2 and HSV-1.

Vitis vinifera represents an important and renowned source of compounds with significant biological activity. Wines and winery bioproducts, such as grape pomace, skins, and seeds, are rich in bioactive compounds against a wide range of human pathogens, including bacteria, fungi, and viruses. However, little is known about the biological properties of vine leaves. The aim of this study was the evaluation of phenolic composition and antiviral activity of Vitis vinifera leaf extract against two human viruses: the Herpes simplex virus type 1 (HSV-1) and the pandemic and currently widespread severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). About 40 phenolic compounds were identified in the extract by HPLC-MS/MS analysis: most of them were quercetin derivatives, others included derivatives of luteolin, kaempferol, apigenin, isorhamnetin, myricetin, chrysoeriol, biochanin, isookanin, and scutellarein. Leaf extract was able to inhibit both HSV-1 and SARS-CoV-2 replication in the early stages of infection by directly blocking the proteins enriched on the viral surface, at a very low concentration of 10 µg/mL. These results are very promising and highlight how natural extracts could be used in the design of antiviral drugs and the development of future vaccines.

Clinical epigenetics settings for cancer and cardiovascular diseases: real-life applications of network medicine at the bedside.

Despite impressive efforts invested in epigenetic research in the last 50 years, clinical applications are still lacking. Only a few university hospital centers currently use epigenetic biomarkers at the bedside. Moreover, the overall concept of precision medicine is not widely recognized in routine medical practice and the reductionist approach remains predominant in treating patients affected by major diseases such as cancer and cardiovascular diseases. By its' very nature, epigenetics is integrative of genetic networks. The study of epigenetic biomarkers has led to the identification of numerous drugs with an increasingly significant role in clinical therapy especially of cancer patients. Here, we provide an overview of clinical epigenetics within the context of network analysis. We illustrate achievements to date and discuss how we can move from traditional medicine into the era of network medicine (NM), where pathway-informed molecular diagnostics will allow treatment selection following the paradigm of precision medicine.

Trifolium Repens Blocks Proliferation in Chronic Myelogenous Leukemia via the BCR-ABL/STAT5 Pathway.

Some species of clover are reported to have beneficial effects in human diseases. However, little is known about the activity of the forage plant Trifolium repens, or white clover, which has been recently found to exert a hepatoprotective action. Scientific interest is increasingly focused on identifying new drugs, especially natural products and their derivatives, to treat human diseases including cancer. We analyzed the anticancer effects of T. repens in several cancer cell lines. The phytochemical components of T. repens were first extracted in a methanol solution and then separated into four fractions by ultra-high-performance liquid chromatography. The effects of the total extract and each fraction on cancer cell proliferation were analyzed by MTT assay and Western blotting. T. repens and, more robustly, its isoflavonoid-rich fraction showed high cytotoxic effects in chronic myelogenous leukemia (CML) K562 cells, with IC50 values of 1.67 and 0.092 mg/mL, respectively. The block of cell growth was associated with a total inhibition of BCR-ABL/STAT5 and activation of the p38 signaling pathways. In contrast, these strongly cytotoxic effects did not occur in normal cells. Our findings suggest that the development of novel compounds derived from phytochemical molecules contained in Trifolium might lead to the identification of new therapeutic agents active against CML.

Comparative Phytochemical Characterization, Genetic Profile, and Antiproliferative Activity of Polyphenol-Rich Extracts from Pigmented Tubers of Different Solanum tuberosum Varieties.

Plants produce a vast array of biomolecules with beneficial effects for human health. In this study, polyphenol and anthocyanin-rich extracts (PAE) from pigmented tubers of Solanum tuberosum L. varieties "Blue Star", "Magenta Love", and "Double Fun" in comparison with the more extensively studied "Vitelotte" were evaluated and compared for antiproliferative effects in human leukemia cells, and their phytochemical and genetic profiles were determined. In U937 cells, upon treatment with PAE, it was possible to reveal the expression of specific apoptotic players, such as caspase 8, 9, 3, and poly (ADP-ribose) polymerase (PARP), as well as the induction of monocyte and granulocyte differentiation. A liquid chromatography/electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) investigation revealed the presence of polyphenolic compounds in all the varieties of potatoes analyzed, among which caffeoyl and feruloyl quinic acid derivatives were the most abundant, as well as several acylated anthocyanins. Each pigmented variety was genotyped by DNA-based molecular markers, and flavonoid-related transcription factors were profiled in tubers in order to better characterize these outstanding resources and contribute to their exploitation in breeding. Interesting biological activities were observed for "Blue Star" and "Vitelotte" varieties with respect to the minor or no effect of the "Double Fun" variety.

Marine-Derived Secondary Metabolites as Promising Epigenetic Bio-Compounds for Anticancer Therapy.

Sessile organisms such as seaweeds, corals, and sponges continuously adapt to both abiotic and biotic components of the ecosystem. This extremely complex and dynamic process often results in different forms of competition to ensure the maintenance of an ecological niche suitable for survival. A high percentage of marine species have evolved to synthesize biologically active molecules, termed secondary metabolites, as a defense mechanism against the external environment. These natural products and their derivatives may play modulatory roles in the epigenome and in disease-associated epigenetic machinery. Epigenetic modifications also represent a form of adaptation to the environment and confer a competitive advantage to marine species by mediating the production of complex chemical molecules with potential clinical implications. Bioactive compounds are able to interfere with epigenetic targets by regulating key transcriptional factors involved in the hallmarks of cancer through orchestrated molecular mechanisms, which also establish signaling interactions of the tumor microenvironment crucial to cancer phenotypes. In this review, we discuss the current understanding of secondary metabolites derived from marine organisms and their synthetic derivatives as epigenetic modulators, highlighting advantages and limitations, as well as potential strategies to improve cancer treatment.

Forskolin Sensitizes Human Acute Myeloid Leukemia Cells to H3K27me2/3 Demethylases GSKJ4 Inhibitor via Protein Kinase A.

Acute myeloid leukemia (AML) is an aggressive hematological malignancy occurring very often in older adults, with poor prognosis depending on both rapid disease progression and drug resistance occurrence. Therefore, new therapeutic approaches are demanded. Epigenetic marks play a relevant role in AML. GSKJ4 is a novel inhibitor of the histone demethylases JMJD3 and UTX. To note GSKJ4 has been recently shown to act as a potent small molecule inhibitor of the proliferation in many cancer cell types. On the other hand, forskolin, a natural cAMP raising compound, used for a long time in traditional medicine and considered safe also in recent studies, is emerging as a very interesting molecule for possible use in cancer therapy. Here, we investigate the effects of forskolin on the sensitivity of human leukemia U937 cells to GSKJ4 through flow cytometry-based assays (cell-cycle progression and cell death), cell number counting, and immunoblotting experiments. We provide evidence that forskolin markedly potentiates GSKJ4-induced antiproliferative effects by apoptotic cell death induction, accompanied by a dramatic BCL2 protein down-regulation as well as caspase 3 activation and PARP protein cleavage. Comparable effects are observed with the phosphodiesterase inhibitor IBMX and 8-Br-cAMP analogous, but not by using 8-pCPT-2'-O-Me-cAMP Epac activator. Moreover, the forskolin-induced enhancement of sensitivity to GSKJ4 is counteracted by pre-treatment with Protein Kinase A (PKA) inhibitors. Altogether, our data strongly suggest that forskolin sensitizes U937 cells to GSKJ4 inhibitor via a cAMP/PKA-mediated mechanism. Our findings provide initial evidence of anticancer activity induced by forskolin/GSKJ4 combination in leukemia cells and underline the potential for use of forskolin and GSKJ4 in the development of innovative and effective therapeutic approaches for AML treatment.

Antiproliferative, antibacterial and antifungal activity of the lichen Xanthoria parietina and its secondary metabolite parietin.

Lichens are valuable natural resources used for centuries throughout the world as medicine, food, fodder, perfume, spices and dyes, as well as for other miscellaneous purposes. This study investigates the antiproliferative, antibacterial and antifungal activity of the acetone extract of the lichen Xanthoria parietina (Linnaeus) Theodor Fries and its major secondary metabolite, parietin. The extract and parietin were tested for antimicrobial activity against nine American Type Culture Collection standard and clinically isolated bacterial strains, and three fungal strains. Both showed strong antibacterial activity against all bacterial strains and matched clinical isolates, particularly against Staphylococcus aureus from standard and clinical sources. Among the fungi tested, Rhizoctonia solani was the most sensitive. The antiproliferative effects of the extract and parietin were also investigated in human breast cancer cells. The extract inhibited proliferation and induced apoptosis, both effects being accompanied by modulation of expression of cell cycle regulating genes such as p16, p27, cyclin D1 and cyclin A. It also mediated apoptosis by activating extrinsic and intrinsic cell death pathways, modulating Tumor Necrosis Factor-related apoptosis-inducing ligand (TRAIL) and B-cell lymphoma 2 (Bcl-2), and inducing Bcl-2-associated agonist of cell death (BAD) phosphorylation. Our results indicate that Xanthoria parietina is a major potential source of antimicrobial and anticancer substances.

Evaluation of a large library of (thiazol-2-yl)hydrazones and analogues as histone acetyltransferase inhibitors: enzyme and cellular studies.

Recently we described some (thiazol-2-yl)hydrazones as antiprotozoal, antifungal and anti-MAO agents as well as Gcn5 HAT inhibitors. Among these last compounds, CPTH2 and CPTH6 showed HAT inhibition in cells and broad anticancer properties. With the aim to identify HAT inhibitors more potent than the two prototypes, we synthesized several new (thiazol-2-yl)hydrazones including some related thiazolidines and pyrimidin-4(3H)-ones, and we tested the whole library existing in our lab against human p300 and PCAF HAT enzymes. Some compounds (1x, 1c', 1d', 1i' and 2m) were more efficient than CPTH2 and CPTH6 in inhibiting the p300 HAT enzyme. When tested in human leukemia U937 and colon carcinoma HCT116 cells (100 µM, 30 h), 1x, 1i' and 2m gave higher (U937 cells) or similar (HCT116 cells) apoptosis than CPTH6, and were more potent than CPTH6 in inducing cytodifferentiation (U937 cells).

Antioxidant, antimicrobial and anti-proliferative activities of Solanum tuberosum L. var. Vitelotte.

Solanum tuberosum L. var. Vitelotte is a potato variety widely used for human consumption. The pigments responsible for its attractive color belong to the class of anthocyanins. The objectives of this study were to characterize and measure the concentration of anthocyanins in pigmented potatoes and to evaluate their antioxidant and antimicrobial activities and their anti-proliferative effects in solid and hematological cancer cell lines. Anthocyanins exert anti-bacterial activity against different bacterial strains and a slight activity against three fungal strains. The Gram-positive bacterium Staphylococcus aureus and the fungus Rhyzoctonia solani were the most affected microorganisms. Antioxidant activities were evaluated by DPPH and FRAP methods; the extract showed a higher reducing capability than anti-radical activity. Moreover, we found that in different cancer cell models the anthocyanins cause inhibition of proliferation and apoptosis in a dose dependent manner. These biological activities are likely due to the high content of malvidin 3-O-p-coumaroyl-rutinoside-5-O-glucoside and petunidin 3-O-p-coumaroyl-rutinoside-5-O-glucoside.

Novel N-hydroxybenzamide-based HDAC inhibitors with branched CAP group.

Ongoing effort to gather further knowledge about the structural requirements on histone deacetylase inhibitors led to the synthesis of novel N-hydroxybenzamide-based HDAC inhibitors 1a-o, introducing branched hydrophobic groups at the capping group, and their inhibition activity against HDACs and anti-proliferation activity in four tumor cell lines were determined. Compounds 1j-o were further tested against recombinant human HDAC1 and HDAC4 to evaluate their selectivity profile. This work further suggests that the chemical nature of the capping group is critical for subtle discrimination between the class I and the class II HDAC isoforms.

Histone acetyltransferase inhibitors and preclinical studies.

BACKGROUND: Drugs able to regulate the histone modifier enzymes are very promising tools for the treatment of several diseases, such as cancer. Histone acetyltransferase (HAT) inhibitors are compounds able to inhibit the catalytic activity of HATs reported to be active in cancer, or in several other diseases, such as Alzheimer (AD), diabetes and hyperlipidaemia. OBJECTIVES: Here we review the status and the rationale for the use of HAT inhibitors in the treatment of various diseases. METHODS: Patents have been found on the espacenet database; the clinical trials have been reported as in the clinicaltrial.gov website. RESULTS AND CONCLUSION: Despite the fact that other drugs able to regulate the histone modifier enzymes (such as histone deacetylase inhibitors) have been already approved for the treatment of cancer, HAT inhibitors seem promising for the treatment of human diseases such as AD and diabetes, although side effects and toxicity need to be investigated.

epigenetic multiple ligands: mixed histone/protein methyltransferase, acetyltransferase, and class III deacetylase (sirtuin) inhibitors.

A number of new compounds bearing two ortho-bromo- and ortho, ortho-dibromophenol moieties linked through a saturated/unsaturated, linear/(poly)cyclic spacer (compounds 1- 9) were prepared as simplified analogues of AMI-5 (eosin), a recently reported inhibitor of both protein arginine and histone lysine methyltransferases (PRMTs and HKMTs). Such compounds were tested against a panel of PRMTs (RmtA, PRMT1, and CARM1) and against human SET7 (a HKMT), using histone and nonhistone proteins as a substrate. They were also screened against HAT and SIRTs, because they are structurally related to some HAT and/or SIRT modulators. From the inhibitory data, some of tested compounds ( 1b, 1c, 4b, 4f, 4j, 4l, 7b, and 7f) were able to inhibit PRMTs, HKMT, HAT, and SIRTs with similar potency, thus behaving as multiple ligands for these epigenetic targets (epi-MLs). When tested on the human leukemia U937 cell line, the epi-MLs induced high apoptosis levels [i.e., 40.7% ( 4l) and 42.6% ( 7b)] and/or massive, dose-dependent cytodifferentiation [i.e., 95.2% ( 1c) and 96.1% ( 4j)], whereas the single-target inhibitors eosin, curcumin, and sirtinol were ineffective or showed a weak effect.

Feijoa sellowiana derived natural Flavone exerts anti-cancer action displaying HDAC inhibitory activities.

Curative properties of some medicinal plants such as the Feijoa sellowiana Bert. (Myrtaceae), have been often claimed, although the corresponding molecular mechanism(s) remain elusive. We report here that the Feijoa acetonic extract exerts anti-cancer activities on solid and hematological cancer cells. Feijoa extract did not show toxic effects on normal myeloid progenitors thus displaying a tumor-selective activity. In the Feijoa acetonic extract, fractionation and subsequent purification and analyses identified Flavone as the active component. Flavone induces apoptosis which is accompanied by caspase activation and p16, p21 and TRAIL over-expression in human myeloid leukemia cells. Use of ex vivo myeloid leukemia patients blasts confirms that both the full acetonic Feijoa extract and its derived Flavone are able to induce apoptosis. In both cell lines and myeloid leukemia patients blasts the apoptotic activity of Feijoa extract and Flavone is accompanied by increase of histone and non-histone acetylation levels and by HDAC inhibition. Our findings show for the first time that the Feijoa apoptotic active principle is the Flavone and that this activity correlates with the induction of HDAC inhibition, supporting the hypothesis of its epigenetic pro-apoptotic regulation in cancer systems.

Estrogens and progesterone promote persistent CCND1 gene activation during G1 by inducing transcriptional derepression via c-Jun/c-Fos/estrogen receptor (progesterone receptor) complex assembly to a distal regulatory element and recruitment of cyclin D1 to its own gene promoter.

Transcriptional activation of the cyclin D1 gene (CCND1) plays a pivotal role in G(1)-phase progression, which is thereby controlled by multiple regulatory factors, including nuclear receptors (NRs). Appropriate CCND1 gene activity is essential for normal development and physiology of the mammary gland, where it is regulated by ovarian steroids through a mechanism(s) that is not fully elucidated. We report here that CCND1 promoter activation by estrogens in human breast cancer cells is mediated by recruitment of a c-Jun/c-Fos/estrogen receptor alpha complex to the tetradecanoyl phorbol acetate-responsive element of the gene, together with Oct-1 to a site immediately adjacent. This process coincides with the release from the same DNA region of a transcriptional repressor complex including Yin-Yang 1 (YY1) and histone deacetylase 1 and is sufficient to induce the assembly of the basal transcription machinery on the promoter and to lead to initial cyclin D1 accumulation in the cell. Later on in estrogen stimulation, the cyclin D1/Cdk4 holoenzyme associates with the CCND1 promoter, where E2F and pRb can also be found, contributing to the long-lasting gene enhancement required to drive G(1)-phase completion. Interestingly, progesterone triggers similar regulatory events through its own NRs, suggesting that the gene regulation cascade described here represents a crossroad for the transcriptional control of G(1)-phase progression by different classes of NRs.