Since it was first observed in late 1970s that human cancers often had decreased manganese superoxide dismutase (MnSOD) protein expression and activity, extensive studies have been conducted to verify the association between MnSOD and cancer. Significance of MnSOD as a primary mitochondrial antioxidant enzyme is unquestionable; results from in vitro, in vivo and epidemiological studies are in h...

BACKGROUND Manganese superoxide dismutase (MnSOD) is a mitochondrial antioxidant enzyme that is down-regulated in a majority of cancers. Due to this observation, as well as MnSOD's potent antioxidant enzymatic activity, MnSOD has been suggested as a tumor suppressor for over 30 years. However, testing this postulate has proven difficult due to the early post-natal lethality of the MnSOD constit...

Manganese superoxide dismutase plasmid liposomes (MnSOD-PL) confer organ-specific in vivo ionizing irradiation protection. To prepare for potential intravenous clinical trials of systemic MnSOD-PL for radioprotection in humans, plasmid and bacterial sequences were removed and a new minicircle construct was tested. Minicircle MnSOD was purified and then cotransfected into 32D cl 3 murine interle...

Manganese Superoxide disimilase (MnSOD) is a member of a family of meta lloenz) mes that catalyze the dismutation of the Superoxide aniÃ3n to I !;<>;. It has been shown that MnSOD activity in tumor cells is lower than that in their normal counterparts. To investigate the molecular basis for the reduced level of MnSOD activity in human tumor cells, the primary structure of human MnSOD has been d...

Manganese superoxide dismutase (MnSOD) plays a critical role in the survival of aerobic life, and its aberrant expression has been implicated in carcinogenesis and tumor resistance to therapy. However, despite extensive studies in MnSOD regulation and its role in cancer, when and how the alteration of MnSOD expression occurs during the process of tumor development in vivo are unknown. Here, we ...

Human manganese superoxide dismutase (MnSOD) is characterized by a product inhibition stronger than that observed in bacterial forms of MnSOD. Previous studies show that the conserved, active-site residue Tyr34 mediates product inhibition; however, the protein environment of Tyr34 is different in human and Escherichia coli MnSOD. We have prepared two site-specific mutants of human MnSOD with re...

Neuronal nitric oxide synthase (nNOS) neurons kill adjacent neurons through the action of NMDA-glutamate receptor activation, although they remain relatively resistant to the toxic effects of NMDA and NO. The molecular basis of the resistance of nNOS neurons to toxic insults is unknown. To begin to understand the molecular mechanisms of the resistance of nNOS neurons, we developed a pheochromac...

Excessive reactive oxygen species are thought to produce oxidative damage that underlies neurodegeneration and cognitive impairment in several disorders including schizophrenia. The functional Ala-9Val polymorphism of the mitochondrial enzyme manganese superoxide dismutase (MnSOD), which detoxifies superoxide radicals to hydrogen peroxide, has been associated with schizophrenia. However, no stu...

The anti-oxidant enzyme system protects cellular macromolecules against damage from reactive oxygen species. One component of this system, manganese superoxide dismutase (MnSOD), has also been shown to display tumor suppressor gene-like activity. The purpose of this study was to examine changes in MnSOD expression during hamster cheek pouch carcinogenesis, and the effects of MnSOD overexpressio...

Manganese superoxide dismutase (MnSOD) has been found to be low in a wide range of tumor cells as well as in vitro-transformed cell lines and has been implicated as a new type of tumor suppressor gene. The relationship between MnSOD activity and the malignant phenotype was studied by transfection of MnSOD cDNA into the SV40-transformed human fibroblast cell line WI-38 VA13 subline 2RA. The inte...