Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.5.1.18 (glutathione S-transferase)
 22,582 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Malignant astrocytomas are frequently resistant to cytotoxic chemotherapy. A possible mechanism of chemoresistance is drug inactivation within malignant astrocytes by detoxifying enzymes (glutathione transferases (GST) and cytochrome P450's). The aim of this study was to assess whether there was differential expression of these detoxifying enzymes in the central nervous system and any relationship to histological grade (WHO) of the tumours. Immunostaining was performed in 30 consecutive glioma samples, using class specific polyclonal antibodies to subtypes of GST (pi, alpha, mu) and to human cytochrome P450 reductase. GST immunostaining was evident in astrocytes and endothelium but not neurones or oligodendrocytes in normal brain. Immunostaining for GST increased in intensity from well differentiated tumours to glioblastoma. Staining was least evident in surrounding normal brain, strong in reactive astrocytes and astrocytic tumour cells and very intense in gemistocytic and giant tumour cells. Small anaplastic tumour cells had very little GST staining. Where endothelial proliferation was evident, GST staining in endothelial cells was increased. Pi was always the predominant subclass, although GST alpha and mu were also expressed in some tumours. Cytochrome P450 reductase immunostaining was present in normal neurones and malignant astrocytes. Gemistocytic astrocytic tumour cells stained intensely. Further work is necessary to see if there is any correlation between immunostaining intensity survival or response to chemotherapy.
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PMID:Glutathione S-transferases and cytochrome P450 detoxifying enzyme distribution in human cerebral glioma. 852 85

Xuefu Zhuyu decoction (XFZYD) is a famous traditional Chinese medicine (TCM) formula, is widely used in the treatment of cardiovascular and cerebrovascular diseases in China over one hundred years. But its effect on antioxidant and drug-metabolizing enzymes are unknown. This study was to observe the effects of Xuefu Zhuyu decoction (XFZYD) on the activities of antioxidant and drug metabolism enzymes (DMEs) in liver of rats. Male SD rats, treated with XFZYD at the dosage of 3.51, 7.02 and 14.04 g x kg(-1) per day for 15 days, serum were collected, tissue fluid, cytosols and microsomes isolated from liver tissues were prepared by centrifugation according to the standard procedure, the activities of antioxidant enzymes and drug-Metabolizing Enzymes were determined by UV-V is spectrophotometer. In serum, the activities of AST was not significantly affected by the treatment with XFZYD, at the high- est dose, the levels of ALT, Cr and BUN were significantly decreased (P < 0.05). GPX were significantly increased at the dose of 7.02, 14.04 g x kg(-1) (P < 0.05), CAT were significantly increased at the highest dose (P < 0.05). T-SOD was not significantly af- fected by this treatment. In the liver tissue, GPX was significantly increased at the dose of 3.51, 7.02 g x kg(-1) (P < 0.05), GST, CAT and T-SOD were not significantly affected following this treatment. In cytosols, GST was significantly increased at the dose of 3.51 g x kg(-1) (P < 0.05), T-SOD was remarkable induced at the dose of 3.51 and 7.02 g x kg(-1) (P < 0.05). In microsomes, XFZYD had no significant effect on Cytochromeb5, NADPH-Cytochrome P450 reductase, CYP3A, CYP2E1 and UGT, XFZYD significantly in- duced GST at the dose of 3.51 and 7.02 g x kg(-1) (P < 0.05), and the level of GSH were significantly increased by XFZYD at the dose of 3.51, 7.02 and 14.04 g kg(-1) (P < 0.05). These findings suggest XFZYD can induce the activities of GPX, CAT, SOD, GST and increase GSH level in liver of rats, which indicate XFZYD may have detoxification and antioxidant functions.
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PMID:[Effects of xuefu zhuyu decoction on antioxidant and drug-metabolizing enzymes in liver of rats]. 2585 Feb 84