Serum dopamine-beta-hydroxylase (DBH) inhibition has been reported in lead workers treated with CaNa2EDTA and in alcoholic patients repeatedly treated with the alcohol aversive drug Disulfiram. The mechanism of inhibition involves Cu++ chelation at the active site of DBH. The effect of CaNa2EDTA and Disulfiram on serum DBH has been compared to the effect of dithiocarbamate pesticides in vitro for the possible use of serum DBH determination for the biological monitoring of workers exposed to these pesticides. Most dithiocarbamates inhibit human serum DBH at micromolar concentrations (range of I50, 0.027-1.6 mumol/L). The inhibitory potency increased from methyl- and dimethyl dithiocarbamates to diethyl dithiocarbamates up to the most potent ethylene bisdithiocarbamates. The I50 of CaNa2EDTA was 3.8 mumol/L, higher than those of dithiocarbamates. Copper addition to the test system reactivated at stoichiometric concentrations dithiocarbamate-inhibited DBH indicating that both base line values and percent of inhibition can be calculated in a single blood sample. Results suggest that serum DBH determination could be useful in case of acute poisoning involving high doses of dithiocarbamate pesticides.
Alcohol Deterrents ; pharmacology ; Biomarkers ; blood ; Chelating Agents ; pharmacology ; Disulfiram ; pharmacology ; Ditiocarb ; pharmacology ; Dopamine beta-Hydroxylase ; blood ; drug effects ; Edetic Acid ; pharmacology ; Female ; Humans ; Male ; Pesticides ; blood

A series of chemotherapeutic drugs that induce DNA damage, such as cisplatin (DDP), are standard clinical treatments for ovarian cancer, testicular cancer, and other diseases that lack effective targeted drug therapy. Drug resistance is one of the main factors limiting their application. Sensitizers can overcome the drug resistance of tumor cells, thereby enhancing the antitumor activity of chemotherapeutic drugs. In this study, we aimed to identify marketable drugs that could be potential chemotherapy sensitizers and explore the underlying mechanisms. We found that the alcohol withdrawal drug disulfiram (DSF) could significantly enhance the antitumor activity of DDP. JC-1 staining, propidium iodide (PI) staining, and western blotting confirmed that the combination of DSF and DDP could enhance the apoptosis of tumor cells. Subsequent RNA sequencing combined with Gene Set Enrichment Analysis (GSEA) pathway enrichment analysis and cell biology studies such as immunofluorescence suggested an underlying mechanism: DSF makes cells more vulnerable to DNA damage by inhibiting the Fanconi anemia (FA) repair pathway, exerting a sensitizing effect to DNA damaging agents including platinum chemotherapy drugs. Thus, our study illustrated the potential mechanism of action of DSF in enhancing the antitumor effect of DDP. This might provide an effective and safe solution for combating DDP resistance in clinical treatment.
Female ; Male ; Humans ; Cisplatin/pharmacology* ; Disulfiram/pharmacology* ; Testicular Neoplasms/drug therapy* ; Fanconi Anemia/drug therapy* ; Alcoholism/drug therapy* ; Drug Resistance, Neoplasm ; Cell Line, Tumor ; Substance Withdrawal Syndrome/drug therapy* ; Apoptosis ; Antineoplastic Agents/therapeutic use* ; Cell Proliferation