Review: The potential of chalcones as a source of drugs

Calix[4]arene chalcone amide C-1011 elicits differential effects on the viability of 4T1 mouse breast adenocarcinoma cells with different levels of adaptor protein Ruk/CIN85 expression

According to our earlier data, calix[4]arene chalcone amides modulate Ca ions exchange in the myometrium mitochondria and the level of inner membrane polarization that can potentially affect cell survival. To test this hypothesis, we studied the effect of calix[4]arene with 4 chalcone amide groups on mitochondria membrane polarization and viability of 4T1 mouse breast adenocarcinoma cells, a surrogate model of human triple-negative breast cancer, and on its highly malignant subline overexpressing the adaptor protein Ruk/CIN85. Mitochondria membrane potential was measured by flow cytometry, and cell viability was assessed using Trypan blue dye exclusion. It was shown that mitochondrial membranes of control (Mock) cells had a higher polarization level (67.80 ± 8.82 r.u., n = 5) compared to 4T1 cells with up-regulation of Ruk/CIN85 (RukUp cells) (25.42 ± 2.58 r.u., n = 4). Upon incubation of cells with 1 μM calix[4]arene C-1011, the CCCP-sensitive component of mitochondrial membranes polarization decreased (by almost 50%) in 4T1 Mock cells and did not change in RukUp cells compared with the control. It was demonstrated that 1 μM calix[4]arene C-1011 suppressed the viability of 4T1 Mock cells by 45%, but did not affect RukUp cells considerably. It was suggested that calix[4]arene chalcone amide С-1011 decreased mouse breast adenocarcinoma 4T1 cell viability­ at least by affecting mitochondrial membrane polarization.The data obtained indicate the prospects of further studies of calix[4]arene chalcone amide as a potential anticancer drug candidate.

4-Hydroxyhalcone effects on cisplatin-induced genotoxicity model

BACKGROUND

The genotoxicity of cisplatin (CP) as a platinum-based antineoplastic agent due to its oxidative stress induction was well known. In this research, we examined 4-hydroxychalcone (4-HCH) as a natural food that presents flavonoid effects on reactive oxygen species (ROS) production and CP-induced in vivo genotoxicity.

METHOD AND MATERIALS

Cytotoxicity of CP and 4-HCH was measured on human embryonic kidney 293 cells with MTT assay. Then, intracellular ROS content at IC50 concentration of CP was measured with 2',7'-dichlorofluorescein diacetate (DCFDA) dye. Finally, 4-HCH was administered intraperitoneally at 10 and 40 mg/kg/BW doses as a pre and post-treatment schedule in a mice model of CP genotoxicity (7 mg/kg). Acridine-orange-stained bone marrow cells were quantified for micronucleus presence examination.

RESULTS

The calculated IC50 of CP and 4-HCH were reported around 19.4 and 133.6 μM, respectively, on HEK293 cells. Also, it was observed that 4-HCH at 0.2, 2 and 10 μM concentrations did not show obvious cytotoxicity. The fluorimetry confirmed that pre-treatment with 10 μM and co-treatment with 2 μM of 4-HCH could attenuate the CP-induced ROS production (P < 0.05 and P < 0.01, respectively). Also, the lowest micronucleated cells were seen in 10 mg/kg 4-HCH-treated group after CP exposure (39 ± 7.9, P < 0.0001).

DISCUSSION

Our results demonstrated the antigenotoxic action of 4-HCH in CP-treated mice bone marrow cells for the first time in both concentrations of 10 and 40 mg/kg especially in the form of co-treatment. Further studies required clinical application of this compound in a combination of CP to attenuate the normal cells' genotoxicity side effects.

Evaluation of the Inhibitory Effects of (E)-1-(2-hydroxy-4,6-dimethoxyphenyl)-3-(naphthalen-1-yl)prop-2-en-1-one (DiNap), a Natural Product Analog, on the Replication of Type 2 PRRSV In Vitro and In Vivo

DiNap [(E)-1-(2-hydroxy-4,6-dimethoxyphenyl)-3-(naphthalen-1-yl)prop-2-en-1-one], an analog of a natural product (the chalcone flavokawain), was synthesized and characterized in this study. Porcine reproductive and respiratory syndrome virus (PRRSV) is the most challenging threat to the swine industry worldwide. Currently, commercially available vaccines are ineffective for controlling porcine reproductive and respiratory syndrome (PRRS) in pigs. Therefore, a pharmacological intervention may represent an alternative control measure for PRRSV infection. Hence, the present study evaluated the effects of DiNap on the replication of VR2332 (a prototype strain of type 2 PRRSV). Initially, in vitro antiviral assays against VR2332 were performed in MARC-145 cells and porcine alveolar macrophages (PAMs). Following this, a pilot study was conducted in a pig model to demonstrate the effects of DiNap following VR2332 infection. DiNap inhibited VR2332 replication in both cell lines in a dose-dependent manner, and viral growth was completely suppressed at concentrations ≥0.06 mM, without significant cytotoxicity. Consistent with these findings, in the pig study, DiNap also reduced viral loads in the serum and lungs and enhanced the weight gain of pigs following VR2332 infection, as indicated by comparison of the DiNap-treated groups to the untreated control (NC) group. In addition, DiNap-treated pigs had fewer gross and microscopic lesions in their lungs than NC pigs. Notably, virus transmission was also delayed by approximately 1 week in uninfected contact pigs within the same group after treatment with DiNap. Taken together, these results suggest that DiNap has potential anti-PRRSV activity and could be useful as a prophylactic or post-exposure treatment drug to control PRRSV infection in pigs.

Antiangiogenic Effect of Flavonoids and Chalcones: An Update

Chalcones are precursors of flavonoid biosynthesis in plants. Both flavonoids and chalcones are intensively investigated because of a large spectrum of their biological activities. Among others, anticancer and antiangiogenic effects account for the research interest of these substances. Because of an essential role in cancer growth and metastasis, angiogenesis is considered to be a promising target for cancer treatment. Currently used antiangiogenic agents are either synthetic compounds or monoclonal antibodies. However, there are some limitations of their use including toxicity and high price, making the search for new antiangiogenic compounds very attractive. Nowadays it is well known that several natural compounds may modulate basic steps in angiogenesis. A lot of studies, also from our lab, showed that phytochemicals, including polyphenols, are potent modulators of angiogenesis. This review paper is focused on the antiangiogenic effect of flavonoids and chalcones and discusses possible underlying cellular and molecular mechanisms.

Novel quinoxalinyl chalcone hybrid scaffolds as enoyl ACP reductase inhibitors: Synthesis, molecular docking and biological evaluation

We report herein, first ever synthesis of series of novel differently substituted quinoxalinyl chalcones using Claisen Schmidt condensation, its molecular docking studies, and potential to be good anti-microbial, anti-tubercular and anti-cancer agents. The antimicrobial studies were carried out against Staphylococcus aureus, Escherichia coli and Candida albicans using disc diffusion procedure. The selected chalcones were tested for anti-cancer and cytotoxicity activity against MCF-7 cancer cell line using MTT assay method. All the synthesized compounds were screened for in vitro anti-tubercular screening against MtbH37RV strains by Alamar blue dye method. These results were compared with molecular docking studies carried out on Mycobacterium tuberculosis enzyme enoyl ACP reductase using Surflex-Dock program that is interfaced with Sybyl-X 2.0. SAR analysis for antimicrobial and antitubercular activity has also been proposed.

Chalcone derivatives cause accumulation of colon cancer cells in the G2/M phase and induce apoptosis

AIMS

Chalcones, naturally occurring open-chain polyphenols abundant in plants, have demonstrated antiproliferative activity in several cancer cell lines. In the present study, the potential anticancer activity of two synthetic analogues named Ch1 and Ch2 in colon cancer cell line was investigated.

MAIN METHODS

Antiproliferative activities of both synthetic analogues were assessed by Growth Inhibition Assay (MTT) and xCELLigence cell analysis. Apoptosis was assessed by annexin V/PI staining (early stage) or by DNA fragmentation (final stage). To study the cell death mechanism induced by tested substances, we assessed a series of assays including measurements of the caspase 3 activity, membrane mitochondrial potential (MMP) changes, reactive oxygen species (ROS) production by flow cytometry and expression of important apoptosis-related genes by realtime PCR.

KEY FINDINGS

We found concentration and time-dependent cytotoxicity, inhibition of proliferation of Caco-2 cells after Ch1 and Ch2 treatment in parallel with G2/M phase cell cycle arrest and increased cell proportion in subG0/G1 population with annexin V positivity. We demonstrated that both Ch1 and Ch2 induced caspase-dependent cell death associated with increased ROS production, suppressed Bcl-2 and Bcl-xL and enhanced Bax expression. Treatment of Ch1 also suppressed α-, α1- and β5-tubulins, on the other hand Ch2 only suppressed α-tubulin expression.

SIGNIFICANCE

Presented chalcones induce apoptosis by intrinsic pathways, and therefore may be an interesting strategy for cancer therapy.