Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P47989 (xanthine oxidase)
8,633 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytotoxic activity of 9 polyprenylalcohols and 6 vitamin K2 derivatives (MK-1 to MK-6) with various lengths of prenyl units was investigated. Among these compounds, geranylgeraniol with 4 prenyl units, and MK-2 with 2 prenyl units, showed the highest cytotoxic activity against human oral tumor cell lines (HSC-2, HSG), without induction of internucleosomal DNA fragmentation. Higher molecular weight compounds showed selective cytotoxicity against tumor cell lines than normal human gingival fibroblasts HGF. ESR spectroscopy showed that all polyprenylalcohols did not produce radical, nor scavenged O2- generated by hypoxanthine and xanthine oxidase reaction, and only slightly enhanced the radical intensity of sodium ascorbate. Vitamin K2 derivatives scavenged O2- more efficiently, but did not produce radical (except MK-3) and only slightly modified the ascorbate radical intensity. Cytotoxic activity of these compounds might be affected by the molecular weight, hydrophobicity, van der Waals area and stabilization of hydration of the molecule.
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PMID:Cytotoxic activity of polyprenylalcohols and vitamin K2 derivatives. 1120 63

Carotenoid fractions were extracted from red paprika, Valencia orange peel and the peel of Golden delicious apple. Thus, hypophasic carotenoids of paprika (PM1), orange (PM3) and apple (PM4), and epiphasic extractions of paprika (PM2) and apple (PM5) were obtained by extraction, saponification and partition between MeOH-H(2)O (9:1) (hypophasic) and hexane (epiphasic). A high content of capsanthin was quantified in hypophasic carotenoids (PM1) from red spice paprika, whereas the hypophasic fractions from orange (PM3) and apple (PM4) were mainly composed of violaxanthin, zeaxanthin and lutein. On the other hand, a high content of beta,beta-carotene and beta-cryptoxanthin was found in epiphasic fractions (PM2 and PM5). The extracts were studied for their anti-Helicobacter pylori (H. pylori), anti-human immunodeficiency virus (HIV), cytotoxic, multidrug resistance (MDR) reversal and radical scavenging activity. Among five PM extracts and beta,betacarotene, PM4 showed potent anti-H. pylori activity (MIC(50) = 36 microg/mL), comparable to metronidazole (MIC(50) = 45 microg/mL). The extracts were inactive against HIV. PM3 and PM4 showed slightly higher cytotoxic activity against three human tumor cell lines (squamous cell carcinoma HSC-2, HSC-3, submandibular gland carcinoma HSG) and human promyelocytic leukemic HL-60 cells than against three normal human oral cells (gingival fibroblast HGF, pulp cell HPC, periodontal ligament fibroblast HPLF), suggesting a tumor-specific cytotoxic activity. PM1, PM3 and PM4 displayed much higher MDR-reversing activity than (+/-)-verapamil. ESR spectroscopy demonstrated that PM1-5 and beta,beta-carotene produced little or no detectable radical under alkaline conditions and did not scavenge the O(2) (-) produced by the hypoxanthine and xanthine oxidase reaction. On the other hand, PM1 and PM2 scavenged efficiently 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, whereas singlet oxygen was also quenched efficiently by PM5 and PM2. The data suggest the potential importance of carotenoids as possible anti-H. pylori and MDR reversal agents. The active principles in the carotenoid extract might differ, depending upon the types of fruits and vegetables.
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PMID:Biological activity of carotenoids in red paprika, Valencia orange and Golden delicious apple. 1617 74