Children with aggressive neural tumors have poor survival rates and novel therapies are needed. Previous studies have identified nifurtimox and buthionine sulfoximine (BSO) as effective agents in children with neuroblastoma and medulloblastoma. We hypothesized that nifurtimox would be effective against other neural tumor cells and would be synergistic with BSO. We determined neural tumor cell v...

Intravenous doses of buthionine sulfoximine (BSO, NSC 326231), an inhibitor of glutathione synthesis, were eliminated rapidly from mouse plasma in a biexponential manner. The initial phase of the plasma concentration versus time curve had a half-life of 4.9 min and accounted for 94% of the total area under the curve. The half-life of the terminal phase of the curve was 36.7 min and the area acc...

The regioselective attack on microsomal phospholipid (PL) polar heads (PH) and fatty acyl chains (FC) demonstrated in vitro has been exploited for the selective quantitation in vivo of the biochemical damages produced by the oxidation and reduction products of CHCl3 metabolism. Five hours after CHCl3 injection (60 mg/kg body weight, ip) to control Sprague-Dawley rats, most of the label covalent...

BACKGROUND Increased intracellular glutathione has long been associated with tumor cell resistance to various cytotoxic agents. An inhibitor of glutathione biosynthesis, L-S,R-buthionine sulfoximine (BSO), has been shown to enhance the cytotoxicity of chemotherapeutic agents in vitro and in vivo. We performed a phase I study of BSO administered with the anticancer drug melphalan to determine th...

Resistance to antineoplastic drugs is a major problem in the clinical management of cancer. Previous studies have demonstrated that the cytotoxicity of certain anticancer drugs is increased by lowering the glutathione (GSH) levels with buthionine sulfoximine (BSO), a specific inhibitor of •¿ v-glutamylcysteine synthetase. In this study we report that the resistance to doxorubicin, an anthracy...

BACKGROUND Alkylator resistance contributes to treatment failure in high-risk neuroblastoma. Buthionine sulfoximine (BSO) can deplete glutathione and synergistically enhance in vitro sensitivity to the alkylating agent melphalan (L-PAM) for many neuroblastoma cell lines, but optimal use of this combination needs to be defined because clinical responses have been less frequent and not durable. ...

Proteins rich in sulfhydryl groups, such as metallothionein, are present in several strains of the parasite Trypanosoma cruzi, the etiological agent of Chagas' disease. Metallothionein-like protein concentrations ranged from 5.1 to 13.2 pmol/mg protein depending on the parasite strain and growth phase. Nifurtimox and benznidazole, used in the treatment of Chagas' disease, decreased metallothion...

Ammonia intoxication, which results in astrocytic edema and glutamine accumulation, blocks cerebral vasodilation during hypercapnia but not during hypoxia. Ammonia's effect on blood flow during hypocapnia is unclear, with some brain regions showing a paradoxical increase in flow. Here, we studied the responses to hypocapnia of pial arterioles not surrounded by astrocytic end feet to avoid mecha...

The role of antioxidants in maintaining the functional integrity of adrenocortical cells during in vitro exposure to endosulfan, an organochlorine pesticide, was investigated in rainbow trout (Oncorhynchus mykiss). Aminotriazole (ATA), an inhibitor of catalase (CAT), L-buthionine sulfoximine (L-BSO), an inhibitor of glutathione (GSH) synthesis, and N-acetyl cysteine (NAC), a glutathione precurs...

Diosbulbin B (DIOB), a hepatotoxic furan-containing compound, is a primary ingredient in Dioscorea bulbifera L., a common herbal medicine. Metabolic activation is required for DIOB-induced liver injury. Protein covalent binding of an electrophilic reactive intermediate of DIOB is considered to be one of the key mechanisms of cytotoxicity. A bromine-based analytical technique was developed to ch...