Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) have been considered to have a beneficial effect against various diseases mediated by reactive oxygen species (ROS). Although a variety of modified recombinant antioxidant enzymes have been generated to protect against the oxidative stresses, the lack of their transduction ability into cells resulted in limited ability to detoxify intracellular ROS. To render the catalase enzyme capable of detoxifying intracellular ROS when added extracellularly, cell-permeable recombinant catalase proteins were generated. A human liver catalase gene was cloned and fused with a gene fragment encoding the HIV-1 Tat protein transduction domain (RKKRRQRRR) and arginine-rich peptides (RRRRRRRRR) in a bacterial expression vector to produce genetic in-frame Tat-CAT and 9Arg-CAT fusion proteins, respectively. The expressed and purified fusion proteins can be transduced into mammalian cells (HeLa and PC12 cells) in a time- and dose-dependent manner when added exogenously in culture medium, and transduced fusion proteins were enzymatically active and stable for 60 h. When exposed to H(2)O(2), the viability of HeLa cells transduced with Tat-CAT or 9Arg-CAT fusion proteins was significantly increased. In combination with transduced SOD, transduced catalase also resulted in a cooperative increase in cell viability when the cells were treated with paraquat, an intracellular antioxide anion generator. We then evaluated the ability of the catalase fusion proteins to transduce into animal skin. This analysis showed that Tat-CAT and 9Arg-CAT fusion proteins efficiently penetrated the epidermis as well as the dermis of the subcutaneous layer when sprayed on animal skin, as judged by immunohistochemistry and specific enzyme activities. These results suggest that Tat-CAT and 9Arg-CAT fusion proteins can be used in protein therapy for various disorders related to this antioxidant enzyme.
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PMID:Transduction of human catalase mediated by an HIV-1 TAT protein basic domain and arginine-rich peptides into mammalian cells. 1172 23

Apoptosis of neurons and astrocytes has been found in patients undergoing AIDS dementia complex. We demonstrated that supernatants from human primary macrophages (M/M) infected by HIV-1 lead human astroglial cells to oxidative stress, as shown by elevated levels of malondialdehyde, and then to apoptosis. Electron microscopy of astrocytes shortly incubated with HIV-1-infected M/M supernatants showed apoptotic blebbing, cytoplasmic loss, and chromatin condensation. Apoptosis was antagonized by pretreating astrocytes with the nonpeptidic superoxide dismutase (SOD) mimetic M40401 but not with anti-HIV-1 compounds, thus showing that apoptosis of astrocytes driven by HIV-1-infected M/M supernatants is mainly mediated by abnormal production of superoxide anions without relationship to HIV-1 replication in such cells. Overall results support the role of oxidative stress mediated by HIV-1-infected M/M as one of the leading causes of neurodegeneration in patients with HIV-1 and suggest the use of nonpeptidic SOD mimetics to counteract HIV-1-related neurological disorders.
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PMID:The contribution of oxidative stress in apoptosis of human-cultured astroglial cells induced by supernatants of HIV-1-infected macrophages. 1178 81

Antioxidant enzymes, such as superoxide dismutase (SOD) and catalase (CAT), have been considered to have a beneficial effect against various diseases that are mediated by the reactive oxygen species (ROS). Although a variety of modified recombinant antioxidant enzymes have been generated to protect against oxidative stresses, the lack of their transduction ability into cells resulted in a limited ability to detoxify intracellular ROS. To render the SOD enzyme capable of detoxifying intracellular ROS when added extracellularly, cell-permeable recombinant SOD proteins were generated. A human Cu,Zn-superoxide dismutase (Cu,Zn-SOD) gene was fused with a gene fragment that encodes the 9 amino acids Tat protein transduction domain (RKKRRQRRR) of HIV-1 and lysine rich peptide (KKKKKKKKK) in a bacterial expression vector in order to produce a genetic in-frame Tat-SOD and 9Lys-SOD fusion protein, respectively. The expressed and purified Tat-SOD and 9Lys-SOD fusion proteins can transduce into human fibroblast cells, and they were enzymatically active and stable for 24 h. The cell viability of the fibroblast cells that were treated with paraquat, an intracellular superoxide anion generator, was increased by the transduced Tat-SOD or 9Lys-SOD. The transduction efficacy of 9Lys-SOD was more efficient than that of Tat-SOD. We evaluated the ability of the SOD fusion pmteins to transduce into animal skin. This analysis showed that Tat-SOD and 9Lys-SOD fusion proteins efficiently penetrated into the epidermis as well as the dermis of the subcutaneous layer, when sprayed on mice skin (judged by the immunohistochemistry and specific enzyme activities). The enzymatic activity of the transduced 9Lys-SOD was higher than that of Tat-SOD, indicating that the penetration of 9Lys-SOD was more efficient when put into the skin. These results suggest Tat-SOD and 9Lys-SOD fusion proteins can be used as anti-aging cosmetics, or in protein therapy, for various disorders that are related to this antioxidant enzyme and ROS.
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PMID:9-polylysine protein transduction domain: enhanced penetration efficiency of superoxide dismutase into mammalian cells and skin. 2044 45

The major cytotoxic activity of Moxa was extracted with CH2Cl2 and partially purified by three cycles of silica gel column chromatography. The active fractions showed higher cytotoxicity against six human tumor cell lines (two oral squamous cell carcinoma, one salivary gland tumor, one melanoma, two leukemia) than three normal oral human cells (gingival fibroblast, periodontal ligament fibroblast, pulp cell). All fractions failed to protect the cells from the cytopathic effect induced by HIV infection. ESR spectroscopy showed that all fractions produced little or no radical under alkaline conditions, while showing much lower O2- scavenging activity, generated by hypoxanthine-xanthine oxidase reaction, than antioxidants and polyphenols. Active fractions induced DNA fragmentation in HL-60 cells, but failed to modify the mobility and activity of mitochondrial Mn-containing superoxide dismutase (MnSOD), in contrast to Moxa smoke. These data suggest that the active principles in the Moxa extract might be different from that in Moxa smoke, which produced carbon radical and modified MnSOD mobility and activity.
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PMID:Partial purification of cytotoxic substances from moxa extract. 1252 96

Infection by human immunodeficiency virus (HIV) causes persistent chronic inflammation. Viral Tat protein plays a role in the intracellular increase of reactive oxygen species (ROS) thus increasing apoptotic index, mostly the one mediated by FAS/CD95, and depleting CD4+ T lymphocytes. The aim of this study was to investigate whether there is a relationship between an extensive array of redox status indices (glutathione (GSH), malondialdehyde (MDA), peroxidation potential, total antioxidant status, glutathione peroxidase (GPx), superoxide dismutase (SOD), total hydroperoxide (TH), DNA fragmentation) and relative CD4, CD95, CD38/CD8 T lymphocyte counts in HIV/AIDS patients compared to healthy subjects. Blood samples from 85 HIV/AIDS patients and 40 healthy subjects were tested by spectrophotometric techniques in order to measure oxidative stress indices, and by flow cytometry to quantify T cell subsets. Patients were divided in two groups according to CDC 1993 guidelines. CD95 and CD38 increase paralleled the severity of HIV infection. Both a reduction of GSH levels and an increase in MDA and TH levels were detected in the plasma of HIV+ patients. These patients also showed an increase of DNA fragmentation in lymphocytes as well as a significant (P<0.05) reduction of GPx and an increase in SOD activity in erythrocytes. Relatively to the control group, HIV-infected patients had significantly differences in global indices of total antioxidant status. These results corroborate that substantial oxidative stress occurs during HIV infection. To our knowledge this study is the first relating oxidative stress indices with both CD38/CD8 and CD95 lymphocytes subsets.
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PMID:Contribution to characterization of oxidative stress in HIV/AIDS patients. 1259 Oct 17

Oxidative signals play an important role in the regulation of endothelial cell adhesion molecule expression. Small GTP-binding protein Rac1 is activated by various proinflammatory substances and regulates superoxide generation in endothelial cells. In the present study, we demonstrate that adenoviral-mediated expression of dominant negative N17Rac1 (Ad.N17Rac1) suppresses tumor necrosis factor-alpha (TNF-alpha)-induced vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin gene expression in a dose-dependent manner. Ad.N17Rac1 did not inhibit TNF-alpha-induced activation of nuclear factor-kappaB (NF-kappaB) binding activity or inhibitor of NF-kappaB-alpha degradation. In contrast, Ad.N17Rac1 inhibited TNF-alpha-induced NF-kappaB-driven HIV(kappaB)(4)-CAT and p288VCAM-Luc promoter activity, suggesting that N17Rac1 inhibits TNF-alpha-induced VCAM-1, E-selectin, and ICAM-1 through suppressing NF-kappaB-mediated transactivation. In addition, expression of superoxide dismutase by adenovirus suppressed TNF-alpha-induced VCAM-1, E-selectin, and ICAM-1 mRNA accumulation. However, adenoviral-mediated expression of catalase only partially inhibited TNF-alpha-induced E-selectin gene expression and had no effect on VCAM-1 and ICAM-1 gene expression. These data suggest that Rac1 and superoxide play crucial roles in the regulation of expression of cell adhesion molecules in endothelial cells.
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PMID:Rac1 and superoxide are required for the expression of cell adhesion molecules induced by tumor necrosis factor-alpha in endothelial cells. 1260 38

We studied the effect of HIV-1 gp160 protein and morphine on murine macrophage and human monocyte apoptosis. gp160 not only promoted murine macrophage apoptosis but also enhanced macrophage iNOS expression/NO generation. gp160 also altered macrophage bax and bcl-2 expression. Morphine enhanced (P<0.001) the effect of gp160 on macrophage apoptosis as well as iNOS expression/NO generation. Nevertheless, both morphine- and gp160-induced murine macrophage apoptosis was attenuated by nitric oxide synthase (NOS) inhibitors (L-NAME and L-NMMA). On the other hand, free radical scavengers such as superoxide dismutase (SOD), dimethylthiourea (DMTU) and catalase attenuated morphine and gp160-induced human monocyte apoptosis.
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PMID:Morphine modulates HIV-1 gp160-induced murine macrophage and human monocyte apoptosis by disparate ways. 1497 89

Reactive oxygen species (ROS) are considered an important mediator in pancreatic beta cell destruction, thereby triggering the development of insulin-dependent diabetes mellitus. In the present study, we investigated the HIV-1 Tat protein transduction domain-mediated transduction of Cu,Zn-superoxide dismutase (SOD), which supplies SOD activity exogenously in pancreatic beta cells under oxidative stress. Tat-SOD fusion protein was successfully delivered into insulin-producing RINm5F cells and rat islet cells. The intracellular dismutation activities of SOD were found to increase in line with the amount of protein delivered into the cells. ROS, nitric oxide-induced cell death, lipid peroxidation, and the DNA fragmentation of insulin-producing cells were found to be significantly reduced when the cells were pretreated with Tat-SOD. Next, we examined the in vivo transduction of Tat-SOD into streptozotocin-induced diabetic mice. A single intraperitoneal injection of Tat-SOD resulted in the delivery of this biologically active enzyme to the pancreas. Moreover, increased radical scavenging activity in the pancreas was induced by multiple injections of Tat-SOD, and this enhanced the tolerance of pancreatic beta cells to oxidative stress. These results suggest that the transduction of Tat-SOD offers a new strategy for protecting pancreatic beta cells from destruction by relieving oxidative stress in ROS-implicated diabetes.
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PMID:HIV-1 Tat-mediated protein transduction of Cu,Zn-superoxide dismutase into pancreatic beta cells in vitro and in vivo. 1522 67

Sulfamethoxazole (SMX) is an effective drug for the management of opportunistic infections, but its use is limited by hypersensitivity reactions, particularly in HIV-infected patients. The oxidative metabolite SMX-nitroso (SMX-NO), is thought to be a proximate mediator of SMX hypersensitivity, and can be reduced in vitro by ascorbate or glutathione. Leukocytes from patients with SMX hypersensitivity show enhanced cytotoxicity from SMX metabolites in vitro; this finding has been attributed to a possible "detoxification defect" in some individuals. The purpose of this study was to determine whether variability in endogenous ascorbate or glutathione could be associated with individual differences in SMX-NO cytotoxicity. Thirty HIV-positive patients and 23 healthy control subjects were studied. Both antioxidants were significantly correlated with the reduction of SMX-NO to its hydroxylamine, SMX-HA, by mononuclear leukocytes, and both were linearly depleted during reduction. Controlled ascorbate supplementation in three healthy subjects increased leukocyte ascorbate with no change in glutathione, and significantly enhanced SMX-NO reduction. Ascorbate supplementation also decreased SMX-NO cytotoxicity compared to pre-supplementation values. Rapid reduction of SMX-NO to SMX-HA was associated with enhanced direct cytotoxicity from SMX-NO. When forward oxidation of SMX-HA back to SMX-NO was driven by the superoxide dismutase mimetic, Tempol, SMX-NO cytotoxicity was increased, without enhancement of adduct formation. This suggests that SMX-NO cytotoxicity may be mediated, at least in part, by redox cycling between SMX-HA and SMX-NO. Overall, these data indicate that endogenous ascorbate and glutathione are important for the intracellular reduction of SMX-NO, a proposed mediator of SMX hypersensitivity, and that redox cycling of SMX-HA to SMX-NO may contribute to the cytotoxicity of these metabolites in vitro.
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PMID:Roles of endogenous ascorbate and glutathione in the cellular reduction and cytotoxicity of sulfamethoxazole-nitroso. 1647 51

This study was performed to investigate the transduction of a full-length superoxide dismutase (SOD) protein fused to transactivator of transcription (Tat) into human chondrocytes, and to determine the regulatory function of transduced Tat-SOD in the inflammatory cytokine induced catabolic pathway. The pTat-SOD expression vector was constructed to express the basic domain of HIV-1 Tat as a fusion protein with Cu, Zn-SOD. We also purified histidine-tagged SOD without an HIV-1 Tat and Tat-GFP as control proteins. Cartilage samples were obtained from patients with osteoarthritis (OA) and chondrocytes were cultured in both a monolayer and an explant. For the transduction of fusion proteins, cells/explants were treated with a variety of concentrations of fusion proteins. The transduced protein was detected by fluorescein labeling, western blotting and SOD activity assay. Effects of transduced Tat-SOD on the regulation of IL-1 induced nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) mRNA expression was assessed by the Griess reaction and reverse transcriptase PCR, respectively. Tat-SOD was successfully delivered into both the monolayer and explant cultured chondrocytes, whereas the control SOD was not. The intracellular transduction of Tat-SOD into cultured chondrocytes was detected after 1 hours, and the amount of transduced protein did not change significantly after further incubation. SOD enzyme activity increased in a dose-dependent manner. NO production and iNOS mRNA expression, in response to IL-1 stimulation, was significantly down-regulated by pretreatment with Tat-SOD fusion proteins. This study shows that protein delivery employing the Tat-protein transduction domain is feasible as a therapeutic modality to regulate catabolic processes in cartilage. Construction of additional Tat-fusion proteins that can regulate cartilage metabolism favorably and application of this technology in in vivo models of arthritis are the subjects of future studies.
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PMID:Transduction of Cu, Zn-superoxide dismutase mediated by an HIV-1 Tat protein basic domain into human chondrocytes. 1679 21


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