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)

We reported (Yarasheski KE, Zachwieja JJ, Gischler J, Crowley J, Horgan MM, and Powderly WG. Am J Physiol Endocrinol Metab 275: E577-E583, 1998) that AIDS muscle wasting was associated with an inappropriately low rate of muscle protein synthesis and an elevated glutamine rate of appearance (Ra Gln). We hypothesized that high plasma HIV RNA caused dysregulation of muscle amino acid metabolism. We determined whether a reduction in HIV RNA (> or =1 log) increased muscle protein synthesis rate and reduced R(a) Gln and muscle proteasome activity in 10 men and 1 woman (22-57 yr, 60-108 kg, 17-33 kg muscle) with advanced HIV (CD4 = 0-311 cells/microl; HIV RNA = 10-375 x 10(3) copies/ml). We utilized stable isotope tracer methodologies ([13C]Leu and [15N]Gln) to measure the fractional rate of mixed muscle protein synthesis and plasma Ra Gln in these subjects before and 4 mo after initiating their first or a salvage antiretroviral therapy regimen. After treatment, median CD4 increased (98 vs. 139 cells/microl, P = 0.009) and median HIV RNA was reduced (155,828 vs. 100 copies/ml, P = 0.003). Mixed muscle protein synthesis rate increased (0.062 +/- 0.005 vs. 0.078 +/- 0.006%/h, P = 0.01), Ra Gln decreased (387 +/- 33 vs. 323 +/- 15 micromol.kg fat-free mass(-1).h(-1), P = 0.04), and muscle proteasome chymotrypsin-like catalytic activity was reduced 14% (P = 0.03). Muscle mass was only modestly increased (1 kg, P = not significant). We estimated that, for each 10,000 copies/ml reduction in HIV RNA, approximately 3 g of additional muscle protein are synthesized per day. These findings suggest that reducing HIV RNA increases muscle protein synthesis and reduces muscle proteolysis, but muscle protein synthesis relative to whole body protein synthesis rate is not restored to normal, so muscle mass is not substantially increased.
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PMID:Reducing plasma HIV RNA improves muscle amino acid metabolism. 1536 96

Advances in HIV infected patients' treatment have modified their prognosis, making possible to consider their admission to the ICU for acute complications. HIV infected patients show nutritional impairments onto which changes due to acute disease are added. Thus, they are candidate to receive specialized nutritional support. The enteral route should be preferred for nutrients supply in case of necessary. With regards to nutritional support characteristics, it should be adapted to the metabolic situation, similarly to what is recommended for other diseases. It has not been demonstrated that the use of substrates with a pharmaco-nutrient capability (glutamine or arginine supplements or modifications in the lipidic component quality) will improve the immunological condition or the clinical curse of patients with HIV infection/AIDS.
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PMID:[Nutritional support in aids patients]. 1598 50

The chemo-enzymatic synthesis of a glycopeptide, which involves the chemical synthesis of N-acetylglucosaminyl peptide and the enzymatic transfer of oligosaccharide, is described. The first step of the chemo-enzymatic method is the chemical synthesis of N-acetylglucosaminyl peptide with an N-acetylglucosamine moiety bound to the asparaginyl residue of the peptide by a solid-phase method. The second step is transglycosylation of a complex-type oligosaccharide derived from a glycopeptide to an N-acetylglucosaminyl peptide by endo-beta-N-acetylglucosaminidase of Mucor hiemalis (Endo-M). Peptide T can block HIV infection of human T cells. We added the sialo-complex-type oligosaccharide to chemically synthesized N-acetylglucosaminyl Peptide T using the transglycosylation activity of Endo-M. The glycosylated Peptide T thus produced showed a higher degree of resistance to protease digestion than Peptide T. We also prepared calcitonin glycopeptide. Calcitonin is a calcium-regulating hormone that is widely used in therapy for hypercalcemia, and is glycosylated by the chemo-enzymatic method described above. This glycopeptide demonstrated sufficient physiological activity. Comparison of NMR data between native calcitonin and calcitonin glycopetide revealed that the glycosylation does not affect the binding topology of the peptide. N-Acetylglucosaminyl glutamine was also a good glycoside acceptor of Endo-M. We were able to add the sialo-complex-type oligosaccharide to the glutamine residue of the Substance P neuropeptide using the transglycosylation activity of Endo-M. The glycosylated Substance P was biologically active, although its activity was rather low, and stable against peptidase digestion. The oligosaccharide moiety attached to the l-glutamine residue of the peptide was not liberated by PNGase that liberated asparagine-linked oligosaccharide from glycopeptides.
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PMID:Chemo-enzymatic synthesis of bioactive glycopeptide using microbial endoglycosidase. 1623 37

Learning and memory impairments are frequently observed in patients suffering from AIDS Dementia Complex (ADC). These effects have been linked to the presence of gp120, an HIV viral coat glycoprotein. The present study investigated the possibility that gp120 prevents the uptake of extracellular glutamate by astrocytes, leading to an interruption of the glutamate-glutamine cycle and a subsequent impairment of memory. Ten microliters of 10nM gp120 was bilaterally injected into the region of the intermediate medial mesopallium of day-old chicks at various times before, or after, training using a single-trial passive avoidance task. Gp120 was found to significantly impair memory retention when injected 10-40 min after training. Memory impairments were evident within 5 min of gp120 administration and remained evident 24h later. Further, the amnestic effect of gp120 could be overcome with glutamine or with precursors of glutamate synthesis, but only weakly by glutamate. These results support the conclusion that the amnestic effect of gp120 is due to an impaired uptake of glutamate by astrocytes and a subsequent interruption of glutamine supply to neurones. The data indicate that the glutamate-glutamine cycle may be a useful therapeutic target in the treatment of ADC.
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PMID:HIV-1 protein gp120 rapidly impairs memory in chicks by interrupting the glutamate-glutamine cycle. 1671 24

Neuronal damage in HIV infection results mainly from chronic activation of brain tissue and involves inflammation, oxidative stress, and glutamate-related neurotoxicity. Glutamate toxicity acts via two distinct pathways: an excitotoxic one, in which glutamate receptors are hyperactivated, and an oxidative one, in which cystine uptake is inhibited, resulting in glutathione depletion, oxidative stress, and cell degeneration. A number of studies have shown that astrocytes normally take up glutamate, keeping extracellular glutamate concentration low in the brain and preventing excitotoxicity. They, in turn, provide the trophic amino acid glutamine via their expression of glutamine synthetase. These protective and trophic actions are inhibited in HIV infection, probably as a result of the effects of inflammatory mediators and viral proteins. In vitro and in vivo studies have demonstrated that activated microglia and brain macrophages (AMM) express the transporters and enzymes of the glutamate cycle. This suggests that in addition to their recognized neurotoxic properties in HIV infection, these cells exhibit some neuroprotective properties, which may partly compensate for the inhibited astrocytic function. This hypothesis might explain the discrepancy between microglial activation, which occurs early in the disease, and neuronal apoptosis and neuronal loss, which are late events. In this review, we discuss the possible neuroprotective and neurotrophic roles of AMM and their relationships with inflammation and oxidative stress.
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PMID:The glutamate-glutamine cycle as an inducible, protective face of macrophage activation. 1691 70

Human immunodeficiency virus type 2 (HIV-2) strains vary widely in their abilities to grow in Old World monkey (OWM) cells such as those of cynomolgus monkeys (CM). We evaluated eight HIV-2 isolates for their sensitivities to CM TRIM5alpha, an anti-HIV factor in OWM cells. We found that different HIV-2 isolates showed differences in their sensitivities to CM TRIM5alpha. Sequence analysis showed that TRIM5alpha-sensitive viruses had proline at the 120th position of the capsid protein (CA), whereas TRIM5alpha-resistant viruses had either alanine or glutamine. Mutagenesis studies indicated that the single amino acid at the 120th position indeed affected the sensitivity of the virus to CM TRIM5alpha.
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PMID:A single amino acid of the human immunodeficiency virus type 2 capsid affects its replication in the presence of cynomolgus monkey and human TRIM5alphas. 1747 50

Humans have evolved complex immune systems to protect against infection by pathogens. However, pathogens possess a remarkable genetic versatility that allows them to gain new vigour and so escape such population immunity. Conflicting pathogen-host objectives, therefore, lead to the evolutionary equivalent of an "arms race". Typically, in this struggle, pathogens attempt to deplete their host of specific nutrients that are essential for immune system function. After infection, the resulting deficiency of nutrient(s) may cause many of the disease symptoms and sequela. In malaria, Plasmodium falciparum, for example, depletes its host of Vitamin A, possibly resulting in blindness in some cases. However, 200,000 International Units of Vitamin A, given to children every three months can reduce significantly their susceptibility to malaria. This would seem to be a minimum child dosage for the treatment of the disease. In contrast, the Coxsackie B virus causes a selenium deficiency that may result in myocardial infarction or Keshan disease. However, table salt fortified with 15ppm anhydrous sodium selenite can cause dramatic drops in the incidence of Keshan disease, while selenium supplementation also reduces re-infarction rates. HIV-1 depletes its host of four nutrients: selenium, cysteine, glutamine and tryptophan, resulting in symptoms known as AIDS. Open and closed clinical trials in South Africa, Zambia and Uganda, involving daily adult doses of 600mcg l-selenomethione, and some 500mg l-glutamine, hydroxytryptophan and N-acetyl cysteine, however, have shown that such supplementation can reverse the symptoms of AIDS and prevent HIV-1 infected patients declining into this disease. It is obvious, therefore, that supplementation of diet with specific nutrients can reduce infection by particular pathogens. In addition, if infection still occurs, their use as a treatment may prevent many of the symptoms and sequela commonly associated with diseases such as malaria, myocardial infarction and AIDS.
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PMID:Host-pathogen evolution: Implications for the prevention and treatment of malaria, myocardial infarction and AIDS. 1759 May 22

Cyanovirin-N (CV-N) is a potent inhibitor of human immunodeficiency virus and many other viruses. It has a high potential for use as a systemic compound to control viral load or in the development of microbicides to prevent primary viral infection. Due to its cyanobacterial origin it is likely to show the typical drawbacks associated with pharmaceutical use of foreign proteins such as short plasma half-life, proteolysis and immunogenicity. Several strategies were used to covalently bond poly(ethylene glycol) (PEGylate) to CV-N. Random PEGylation at lysine residues resulted in poor retention of antiviral activity. Many site-directed mutants were made to test site-specific PEGylation. One mutant, where glutamine 62 was replaced with cysteine (CV-N(Q62C)) and PEGylated with maleimide activated PEG, retained significant anti-HIV activity in vitro.
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PMID:PEGylation of cyanovirin-N, an entry inhibitor of HIV. 1788 38

12B75, 274150; Abacavir sulfate/lamivudine, Abatacept, Ad2/HIF-1alpha, Adalimumab, Adefovir, Adefovir dipivoxil, AGN-201904-Z, AIDSVAX, Albinterferon alfa-2b, Alemtuzumab, Aliskiren fumarate, Alvimopan hydrate, Amlodipine besylate/atorvastatin calcium, Amlodipine besylate/Olmesartan medoxomil, Ammonium tetrathiomolybdate, Amodiaquine, Apaziquone, Aprepitant, Arsenic trioxide, Artesunate/Amodiaquine, Ascorbic acid, Atazanavir sulfate, Atazanavir/ritonavir, Atomoxetine hydrochloride, Atrigel-Leuprolide, Axitinib; Bevacizumab, Binodenoson, Bortezomib, Bovine lactoferrin; Calcipotriol/betamethasone dipropionate, Carisbamate, Certolizumab pegol, Ciclesonide, Conivaptan hydrochloride, CP-690550, CP-751871, Cypher; Dapivirine, Darbepoetin alfa, Darunavir, Dasatinib, del-1 Genemedicine, Denosumab, Desloratadine, Dexlansoprazole, DiabeCell, Drospirenone/ethinylestradiol, DTaP-HepB-IPV, Duloxetine hydrochloride, Dutasteride; Eculizumab, Eldecalcitol, Eletriptan, Emtricitabine, Entecavir, Eritoran tetrasodium, Ertapenem sodium, Escitalopram oxalate, Eslicarbazepine acetate, Esomeprazole magnesium, Estradiol acetate, Eszopiclone, ETEC vaccine, Etoricoxib, Exenatide, Ezetimibe; Fluticasone furoate, Fosmidomycin, Fosmidomycin/clindamycin; Glutamine; Heat Shock Protein 10, Hepatitis B hyperimmunoglobulin, HIV vaccine, Hochuekki-to, Human Albumin, Human papillomavirus vaccine; Immune globulin subcutaneous [human], IMP-321, Interferon omega, ISIS-301012, Istaroxime; Japanese encephalitis virus vaccine; Latanoprost/timolol maleate, Lenalidomide, Linaclotide acetate, Lumiracoxib, LY-517717; Malaria vaccine, MAS-063D, Meningitis B vaccine, Mepolizumab, Methylnaltrexone bromide, Micafungin sodium, MK-0822A, Morphine glucuronide, Morphine hydrochloride, Mycophenolic acid sodium salt; Natalizumab, Nesiritide, Norelgestromin/ethinyl estradiol, NT-201; Oblimersen sodium, Olmesartan medoxomil, Olmesartan medoxomil/hydrochlorothiazide, Omalizumab, Otamixaban; Paclitaxel nanoparticles, Panitumumab, Panobinostat, Parathyroid hormone (human recombinant), Parecoxib sodium, Pegfilgrastim, Peginterferon alfa-2a, Peginterferon alfa-2b, Pegvisomant, PI-88, Pimecrolimus, Pneumococcal 7-valent conjugate vaccine, Pneumococcal 9-valent conjugate vaccine, Pneumococcal conjugate vaccine, Poloxamer-188, Prasugrel, Pregabalin, Prulifloxacin; R-109339, Ramipril/amlodipine, Ranolazine, Rasburicase, rHA influenza vaccine, Ro-50-3821, Rosuvastatin calcium, Rotavirus vaccine, Rotigotine, Ruboxistaurin mesilate hydrate; Satavaptan, SC-75416, Solifenacin succinate, Sorafenib, Sugammadex sodium, Sunitinib malate, Synthetic conjugated estrogens B; Tadalafil, Talnetant, Taxus, Tegaserod maleate, Telbivudine, Temsirolimus, Tenofovir disoproxil fumarate, Tetomilast, Tiotropium bromide, Tipifarnib, Tofimilast, Tremelimumab, Trimethoprim; Udenafil, Urocortin 2; Valdecoxib, Vernakalant hydrochloride; XP-828L.
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PMID:Gateways to clinical trials. 1798 11

HIV-1 Associated Dementia (HAD) is a significant consequence of HIV infection. Although multiple inflammatory factors contribute to this chronic, progressive dementia, excitotoxic damage appears to be an underlying mechanism in the neurodegenerative process. Excitotoxicity is a cumulative effect of multiple processes occurring in the CNS during HAD. The overstimulation of glutamate receptors, an increased vulnerability of neurons, and disrupted astrocyte support each potentiate excitotoxic damage to neurons. Recent evidence suggests that poorly controlled generation of glutamate by phosphate-activated glutaminase may contribute to the neurotoxic state typical of HAD as well as other neurodegenerative disorders. Glutaminase converts glutamine, a widely available substrate throughout the CNS to glutamate. Inflammatory conditions may precipitate unregulated activity of glutaminase, a potentially important mechanism in HAD pathogenesis.
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PMID:Potentiation of Excitotoxicity in HIV-1 Associated Dementia and the Significance of Glutaminase. 1805 78


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