Homobutein

In Vitro Screening to Identify Anti-Toxoplasma Compounds and In Silico Modeling for Bioactivities and Toxicity.[Pubmed:31543702]

Yale J Biol Med. 2019 Sep 20;92(3):369-383. eCollection 2019 Sep.

Toxoplasmosis, which affects more than a billion people worldwide, is a common parasitic infection caused by the obligate intracellular parasite, Toxoplasma gondii. Current treatment strategies have several limitations, including unwanted side effects and poor efficacy. Therefore, newer therapies are needed for toxoplasmosis. Drug repurposing and screening of a vast array of natural and/or synthetic compounds is a viable option for antiparasitic drug discovery. In this study, we screened 62 compounds comprising natural products (NPs) and FDA-approved (FDA) drugs, to identify the hit compounds that suppress the growth of T. gondii. To determine the parasite inhibitory potential of the compounds, host mammalian cells were infected with a transgenic T. gondii strain, and the viability of the parasite was evaluated by luminescence. Of the 62 compounds, tubericidin, sulfuretin, peruvoside, resveratrol, narasin and diacetoxyscirpenol of the natural product isolates, as well as bortezonib, 10-Hydroxycamtothecin, mebendazole, niflumic acid, clindamycin HCl, mecamylamine, chloroquine, mitomycin C, fenbendazole, daunorubicin, atropine, and cerivastatin of FDA molecules were identified as "hits" with >/= 40 percent anti-parasite action. Additionally, mitomycin C, radicicol, naringenin, gitoxigenin, menadione, botulin, genistin, Homobutein, and gelsemin HCl of the natural product isolates, as well as lomofungin, cyclocytidine, prazosin HCl, cerivastatin, camptothecin, flufenamic acid, atropine, daunorubicin, and fenbendazole of the FDA compounds exhibited cytotoxic activity, reducing the host viability by >/= 30 percent. Our findings not only support the prospects of drug repurposing, but also indicate that screening a vast array of molecules may provide viable sources of alternative therapies for parasitic infection.

Natural chalcones as dual inhibitors of HDACs and NF-kappaB.[Pubmed:22710558]

Oncol Rep. 2012 Sep;28(3):797-805.

Histone deacetylase enzymes (HDACs) are emerging as a promising biological target for cancer and inflammation. Using a fluorescence assay, we tested the in vitro HDAC inhibitory activity of twenty-one natural chalcones, a widespread group of natural products with well-known anti-inflammatory and antitumor effects. Since HDACs regulate the expression of the transcription factor NF-kappaB, we also evaluated the inhibitory potential of the compounds on NF-kappaB activation. Only four chalcones, isoliquiritigenin (no. 10), butein (no. 12), Homobutein (no. 15) and the glycoside marein (no. 21) showed HDAC inhibitory activity with IC50 values of 60-190 microM, whereas a number of compounds inhibited TNFalpha-induced NF-kappaB activation with IC50 values in the range of 8-41 microM. Interestingly, three chalcones (nos. 10, 12 and 15) inhibited both TNFalpha-induced NF-kappaB activity and total HDAC activity of classes I, II and IV. Molecular modeling and docking studies were performed to shed light into dual activity and to draw structure-activity relationships among chalcones (nos. 1-21). To the best of our knowledge this is the first study that provides evidence for HDACs as potential drug targets for natural chalcones. The dual inhibitory potential of the selected chalcones on NF-kappaB and HDACs was investigated for the first time. This study demonstrates that chalcones can serve as lead compounds in the development of dual inhibitors against both targets in the treatment of inflammation and cancer.