OBJECTIVE: To investigate the protective effects of stir-fried Semen Armeniacae Amarum (SAA) against aristolochic acid I (AAI)-induced nephrotoxicity and DNA adducts and elucidate the underlying mechanism involved for ensuring the safe use of Asari Radix et Rhizoma. METHODS: In vitro, HEK293T cells overexpressing Flag-tagged multidrug resistance-associated protein 3 (MRP3) were constructed by Lentiviral transduction, and inhibitory effect of top 10 common pairs of medicinal herbs with Asari Radix et Rhizoma in clinic on MRP3 activity was verified using a self-constructed fluorescence screening system. The mRNA, protein expressions, and enzyme activity levels of NAD(P)H quinone dehydrogenase 1 (NQO1) and cytochrome P450 1A2 (CYP1A2) were measured in differentiated HepaRG cells. Hepatocyte toxicity after inhibition of AAI metabolite transport was detected using cell counting kit-8 assay. In vivo, C57BL/6 mice were randomly divided into 5 groups according to a random number table, including: control (1% sodium bicarbonate), AAI (10 mg/kg), stir-fried SAA (1.75 g/kg) and AAI + stir-fried SAA (1.75 and 8.75 g/kg) groups, 6 mice in each group. After 7 days of continuous gavage administration, liver and kidney damages were assessed, and the protein expressions and enzyme activity of liver metabolic enzymes NQO1 and CYP1A2 were determined simultaneously. RESULTS: In vivo, combination of 1.75 g/kg SAA and 10 mg/kg AAI suppressed AAI-induced nephrotoxicity and reduced dA-ALI formation by 26.7%, and these detoxification effects in a dose-dependent manner (P<0.01). Mechanistically, SAA inhibited MRP3 transport in vitro, downregulated NQO1 expression in vivo, increased CYP1A2 expression and enzymatic activity in vitro and in vivo, respectively (P<0.05 or P<0.01). Notably, SAA also reduced AAI-induced hepatotoxicity throughout the detoxification process, as indicated by a 41.3% reduction in the number of liver adducts (P<0.01). CONCLUSIONS Stir-fried SAA is a novel drug candidate for the suppression of AAI-induced liver and kidney damages. The protective mechanism may be closely related to the regulation of transporters and metabolic enzymes.
Aristolochic Acids/toxicity* ; Animals ; Humans ; NAD(P)H Dehydrogenase (Quinone)/genetics* ; HEK293 Cells ; Kidney/pathology* ; Cytochrome P-450 CYP1A2/genetics* ; Mice, Inbred C57BL ; DNA Adducts/drug effects* ; Male ; Kidney Diseases/drug therapy* ; Drugs, Chinese Herbal/therapeutic use* ; Mice ; Prunus armeniaca ; Plant Extracts

Wogonin is a plant flavonoid compound extracted from Scutellaria baicalensis (Huang-Qin or Chinese skullcap) and has been studied thoroughly by many researchers till date for its anti-viral, anti-oxidant, anti-cancerous and neuro-protective properties. Numerous experiments conducted in vitro and in vivo have demonstrated wogonin's excellent tumor inhibitory properties. The anti-cancer mechanism of wogonin has been ascribed to modulation of various cell signaling pathways, including serine-threonine kinase Akt (also known as protein kinase B) and AMP-activated protein kinase (AMPK) pathways, p53-dependent/independent apoptosis, and inhibition of telomerase activity. Furthermore, wogonin also decreases DNA adduct formation with a carcinogenic compound 2-Aminofluorene and inhibits growth of drug resistant malignant cells and their migration and metastasis, without any side effects. Recently, newly synthesized wogonin derivatives have been developed with impressive anti-tumor activity. This review is the succinct appraisal of the pertinent articles on the mechanisms of anti-tumor properties of wogonin. We also summarize the potential of wogonin and its derivatives used alone or as an adjunct therapy for cancer treatment. Furthermore, pharmacokinetics and side effects of wogonin and its analogues have also been discussed.
Animals ; Antineoplastic Agents, Phytogenic ; pharmacology ; therapeutic use ; DNA Adducts ; metabolism ; Drug Resistance, Neoplasm ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Flavanones ; pharmacology ; therapeutic use ; Humans ; Neoplasms ; drug therapy ; metabolism ; Phytotherapy ; Scutellaria baicalensis ; chemistry ; Signal Transduction ; drug effects

OBJECTIVEThe oxidation of benzo (a) pyrene mediated by 5-lipoxygenase (5-LOX) were investigated in HBE cells in order to provide further proof that lipoxygenase is the alternative pathway for the oxidation of xenobiotics.

METHODSEnzymic experiment: Soybean lipoxygenase (SLO), substrate (benzo[a] pyrene) and other component react in the enzymic system and the reaction product are detected by spectrophotometry. At the same time, in vitro detect of benzo (a) pyrene-DNA adducts with a UV spectrophotometer and HPLC. Cellular experiment: After HBE cells exposure to different poison (B[a]P 4, 8, 16, 32, 64, 128µmol/L, AA-861, naproxen or α- naphthoflavone 0.1, 1, 10 µmol/L) for 24 hours, the effect of benzo (a) -pyrene on cell survival rate were assessed by reductions of tetrazolium dye (MTT) and flow cytometry in cultured HBE cells, and the protein expressions of 5-lipoxygenase in the cells are tested by western-blot, and the DNA damages by the single cell gel electrophoresis. And then, the effect of the specific inhibitor of 5-lipoxygenase (AA-861) on 5-lipoxygenase protein expression and DNA damage in the cells are detected.

RESULTSSLO can catalyze the co-oxidation of benzo (a) pyrene to generate benzo (a) pyrene-7,8-epoxide in the presence of hydrogen peroxide. GTP can inhibit the reaction , the IC50 value is 0.46 mg/L, the model equation is Probit (P) = 0.8985+2.6824 Log (dose). SLO can catalyze the co-oxidation of benzo (a) pyrene to generate a new product, but fail to form DNA adducts in vitro. HBE cell viability decreased with the benzo (a) pyrene concentration increased , but AA-861 and naproxen can inhibit it. Flow cytometry and single cell gel electrophoresis experiments show, Benzo (a) pyrene can induce 5-lipoxygenase protein expression, but AA-861 cannot in HBE. Benzo (a) pyrene causes toxic action and DNA damage in HBE, which can significantly inhibit by AA-861, the difference is statistically significant (P < 0.05).

CONCLUSIONSThe co-oxidate of benzo (a) pyrene by 5-LOX turns into electrophiles that covalently bind to DNA and induce DNA damage, which can be significantly inhibited by AA-861.

Benzo(a)pyrene ; metabolism ; Cells, Cultured ; DNA Adducts ; metabolism ; DNA Damage ; Epithelial Cells ; drug effects ; metabolism ; Humans ; Lipoxygenase ; pharmacology

OBJECTIVETo study the genotoxicity effect of environmental tobacco side-stream smokes (ETSS) on oxidative DNA damage and its molecular mechanism.

METHODSDNA adduct 8-hydroxydeoxyguanosine (8-OHdG) was used as a biomarker of oxidative DNA damage. The level of 8-OHdG in DNA exposed to ETSS was detected by high performance liquid chromatography with electrochemical detection. Organic and inorganic components in ETSS were analyzed by gas chromatography-mass spectrum and atomic absorption spectrum respectively.

RESULTSParticle matters (PMs) and volatile organic compounds (VOCs) in ETSS could directly induce oxidative DNA damage and formation of 8-OHdG. There were 123 and 84 kinds of organic components in PMs and VOCs respectively, and 7 kinds of inorganic components in ETSS. Some components, especially quinones and polyphenols in ETSS, could produce free radicals in vitro by auto-oxidation without any biological activity systems, and with the catalytic reaction of metals, the DNA adduct 8-OHdG was produced.

CONCLUSIONETSS have biological oxidative effect on DNA in vitro and in vivo, and expressed direct genotoxicity. 8-OHdG is a valuable biomarker of oxidative DNA damage.

Animals ; Biomarkers ; analysis ; Cattle ; DNA ; drug effects ; metabolism ; DNA Adducts ; analysis ; DNA Damage ; Deoxyguanosine ; analogs & derivatives ; analysis ; Female ; Lung ; chemistry ; metabolism ; Metals, Heavy ; analysis ; Organic Chemicals ; analysis ; Oxidation-Reduction ; Rats ; Tobacco Smoke Pollution ; adverse effects ; analysis