Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Preparative isoelectric focusing and gel filtration chromatography were used to purify a carboxypeptidase produced by the entomopathogenic fungus Metarhizium anisopliae during growth on cockroach cuticle. The enzyme was inhibited by diisopropyl fluorophosphate, implying involvement of a serine residue in catalysis. However, the M. anisopliae enzyme differed from most serine carboxypeptidases in also being inhibited by the metal chelator 1,10-phenanthroline and in being a small (30 kDa), basic (pI 9.97) protein with a neutral pH optima (pH 6.8). These properties resemble those exhibited by some metalloproteases but the enzyme is not inhibited by Cd2+; nor do Zn2+ or Co2+ restore activity in enzyme inhibited with phenanthroline. The amino-terminal sequence (22 residues) showed no similarity to other protein sequences. Unlike previously reported fungal carboxypeptidases, the M. anisopliae enzyme is powerfully inhibited by potato carboxypeptidase inhibitor. The carboxypeptidase shows a broad primary specificity toward amino acids with hydrophobic side groups in a series of N-blocked dipeptides, with substrates with phenylalanine being the most rapidly hydrolyzed. The S1 subsite also accommodated Glu, confirming its low selectivity. Proline at P1 or P1 resulted in a very poor substrate. The specificity of the carboxypeptidase complements that of the subtilisin-like protease (Pr1) of M. anisopliae. Both Pr1 and the carboxypeptidase are produced during carbon and nitrogen deprivation, which indicates that the exopeptidase functions with Pr1 to degrade peptides to supply amino acids during starvation and pathogenicity.
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PMID:Characterization of a novel carboxypeptidase produced by the entomopathogenic fungus Metarhizium anisopliae. 797 80

The expression of the 60-kDa heat-shock protein (HSP60) varies markedly among patients with ovarian carcinoma, and high-level expression predicts poor survival in such patients treated with cisplatin (DDP)-containing chemotherapy programs. We investigated the expression of HSP60 in human ovarian carcinoma 2008 cells and an 11-fold DDP-resistant subline 2008/C13*5.25. Heating for 2 h at 44 degrees C produced a 2.7 +/- 0.16-fold increase (mean +/- SD) that was maximal at 4 h after the start of heat exposure. Exposure to an IC50 concentration of DDP for 1 h induced a 1.8 +/- 0.03-fold increase in hsp60 expression. The opposite was true for cadmium and zinc, both of which induced increases in metallothionein IIA but not in the hsp60 message. 2008/C13*5.25 cells constitutively over-expressed hsp60 mRNA by 1.7 +/- 0.16 orders of magnitude and contained a 3.8 +/- 0.45-fold higher level of HSP60 as detected by immunocytochemical staining. 2008/C13*5.25 cells showed 1.2-fold cross-resistance to thermal killing. Expression of hsp60 was markedly reduced in 2008 xenografts as compared with 2008 cells growing in vitro; however, neither serum starvation nor refeeding altered the message level. Exposure to a variety of growth factors and drug treatments known to alter the DDP sensitivity of 2008 cells, including epidermal growth factor, 12-O-tetradecanoylphorbol-13-acetate, buthionine sulfoximine, ouabain, and forskolin, did not alter hsp60 expression. These results suggest a role for HSP60 in mediating resistance to both DDP and hyperthermia but indicate that the hsp60 mRNA levels are not regulated by the factors listed above.
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PMID:Regulation of HSP60 mRNA expression in a human ovarian carcinoma cell line. 810 Jul 43

Although the relationship between starvation and reduced resistance to infection has been suggested by historical accounts of famines and pestilence and by recent epidemiologic studies, the concept of nutritional deficiency causing impairment of immunocompetence is relatively recent. In PEM (protein-energy malnutrition), most of the host defence mechanisms are breached, especially manifested in reduced cell-mediated immunity. One plausible reason is the reduction in mature fully differentiated T lymphocytes. Recent immunological methods made it possible to analyze its precise mechanism and process in detail. Naturally occurring states of malnutrition are difficult to interpret largely because deficiencies usually involve multiple dietary factors. It is obvious that single nutrients can only be analyzed in defined and controlled animal experiments. Role of micronutrients such as zinc, iron, and vitamins, specific amino acids such as arginine, glutamine, and fat on immunological responses have been paid attention on their specific actions and some of them have been investigated in humans as well.
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PMID:[Role of malnutrition on immunity]. 812 95

The effects of short-term starvation on serum and tissue levels of zinc, metallothionein (MT), and the activity of alkaline phosphatase (EC 3.1.3.1, ALP) were investigated with 6-month-old rats. The rats were fed a diet with adequate zinc (92mg/kg of Zn, 1.12% phytic acid) before they were starved for 0h (control), 12h, 24h, and 36h and then killed by decapitation. Fasting was accompanied by typical changes in serum parameters such as reduced glucose and protein concentrations, elevated ketogenesis, and a rapid breakdown of liver glycogen. Fasting did not alter serum zinc levels, but it did lead to a significant elevation in the percent of unsaturated serum-zinc binding capacity. Liver concentrations of zinc and MT, based both on fresh and dry weight, were increased throughout starvation. However, total liver zinc was reduced by up to 23% in response to fasting and total liver MT was slightly elevated. The increased concentrations of liver zinc and MT are, therefore, mainly a consequence of reduced liver weight. A part of the liver zinc, however, was bound to newly synthesized MT to prevent greater zinc loss. Starvation evoked no altered mucosa MT levels. Changes in kidney zinc and kidney medulla MT caused by starvation were small and not significant. In contrast to this observation some variation of kidney cortex MT was apparent. Starvation produced a permanent reduction of the serum and intestinal activity of ALP. In the liver and the medulla of the kidneys no significant differences of ALP activity could be observed. However, kidney cortex ALP was induced after 36h of fasting.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Zinc metabolism in fasted rats. 815 85

A new member of the yeast yAP family, designated YAP2, has been isolated and characterized. The protein displays a high homology with the DNA-binding domain of yAP-1, which contains a basic DNA-binding domain and leucine zipper motif and binds in vitro to the same cis-element. Growth arrest of yeast caused by low concentrations of 1,10-phenanthroline, resulting in zinc and/or iron deprivation, is overcome by over-expression of YAP1 or YAP2. In fact, yeast cells over-expressing YAP1 or YAP2 display pleiotropic drug resistance. On the other hand, a yap2 null mutant has an increased thermotolerance under starvation conditions caused by 1,10-phenanthroline. The latter mutant might become an excellent tool in the study of pathways leading toward thermotolerance acquisition.
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PMID:Overexpression of YAP2, coding for a new yAP protein, and YAP1 in Saccharomyces cerevisiae alleviates growth inhibition caused by 1,10-phenanthroline. 822 90

The role of Ca2+ and Zn2+ in the initiation of DNA synthesis in NIH 3T3 fibroblasts and c-Ha-ras(val-12) oncoprotein-expressing (NIH 3T3) cells has been studied. Entrapment of the Ca2+ chelator, BAPTA (30 microM), into the cells totally blocked a serum-induced rise in cytosolic free Ca2+ ([Ca2+]i) as determined with fura-2. Serum starvation for 24 h considerably reduced DNA synthesis in control NIH 3T3 fibroblasts. BAPTA treatment reduced serum-induced DNA synthesis and totally inhibited platelet-derived growth factor-induced DNA synthesis in these cells. DNA synthesis of the c-Ha-ras(val-12)-expressing fibroblasts was little affected by serum starvation and unaffected by entrapment of BAPTA into the cells. Intracellular Zn2+ was measured using the fluorescent probe TSQ in intact cells. As determined using image analysis the TSQ fluorescence was distributed throughout the cytoplasm and concentrated around the nucleus. The permeable Zn2+ chelator, TPEN, at a concentration of 10 microM, caused a maximal reduction in TSQ-available Zn2+. This concentration of TPEN totally blocked DNA synthesis both in control and c-Ha-ras(val-12)-expressing fibroblasts. Upon addition of 11 microM Zn2+ DNA synthesis was restored even after TPEN addition. [3H]Thymidine incorporation itself was also sensitive to TPEN treatment. The results suggest that c-Ha-ras(val-12)-induced proliferation is independent of changes in [Ca2+]i. A specific role of Zn2+ in c-Ha-ras-induced proliferation is unlikely since ras-expressing and control cells reacted similarly to Zn2+ deprivation. There seems to be a constant requirement for the presence of Zn2+ in cell proliferation.
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PMID:Ca2+ and Zn2+ dependence of DNA synthesis in untransformed and in Ha-ras(val-12)-expressing NIH 3T3 cells. 835 24

Anorexia nervosa (AN) and bulimia nervosa (BN) are potentially fatal eating disorders which primarily affect adolescent females. Differentiating eating disorders from primary gastrointestinal (GI) disease may be difficult. GI disorders are common in eating disorder patients, symptomatic complaints being seen in over half. Moreover, many GI diseases sometimes resemble eating disorders. Inflammatory bowel disease, acid peptic diseases, and intestinal motility disorders such as achalasia may mimic eating disorders. However, it is usually possible to distinguish these by applying the diagnostic criteria for eating disorders and by obtaining common biochemical tests. The primary features of AN are profound weight loss due to self starvation and body image distortion; BN is characterized by binge eating and self purging of ingested food by vomiting or laxative abuse. GI complications in eating disorders are common. Recurrent emesis in BN is associated with dental abnormalities, parotid enlargement, and electrolyte disturbances including metabolic alkalosis. Hyperamylasemia of salivary origin is regularly seen, but may lead do an erroneous diagnosis of pancreatitis. Despite the weight loss often seen in eating disorders, serum albumin, cholesterol, and carotene are usually normal. However, serum levels of trace metals such as zinc and copper often are depressed, and hypophosphatemia can occur during refeeding. Patients with eating disorders frequently have gastric emptying abnormalities, causing bloating, postprandial fullness, and vomiting. This usually improves with refeeding, but sometimes treatment with pro-motility agents such as metoclopromide is necessary. Knowledge of the GI manifestations of eating disorders, and a high index of suspicion for one condition masquerading as the other, are required for the correct diagnosis and management of these patients.
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PMID:Gastrointestinal and nutritional aspects of eating disorders. 840 9

Malnutrition causes an array of metabolic alterations that affect wound healing. Stressed starvation, in which essential protein stores in lean body mass and viscera are utilized, is of utmost concern. Hospital-related malnutrition usually presents as a combination of both protein and energy malnutrition. Key nutrients play specific roles in wound healing. For example, vitamin C is essential for collagen synthesis, vitamin A enhances epithelialization, and zinc is necessary for cell mitosis and cell proliferation. Modern methods are available to determine an array of serum nutrient levels; however, these investigations are often inadequate, because serum levels of specific nutrients frequently do not reflect the total body content. Therefore the common association between generalized malnutrition and deficiencies of specific nutrients must be recognized. By using current nutritional techniques such as anthropometrics, albumin, transferrin, and immune status, one could determine nutritional deficiencies and thereby could replete all nutrients, including protein, carbohydrate, fat, vitamins, and minerals, through either parenteral or enteral support.
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PMID:Effects of nutritional status on wound healing. 850 82

To evaluate the specificity of some functional indices in assessment of body zinc nutrition status, we used experimental rat model to observe the effects of some factors, such as forced swimming, starvation, trauma and alcohol intoxication on zinc the status. Plasma zinc levels of rats significantly decreased after trauma increased after starvation. Liver zinc content showed a rising tendency in trauma and starvation rats. Activities of superoxide dismutase in red blood cells and alkaline phosphatase, mannosidase, 5'-nucleotidase in plasma of rats with alcohol intoxication declined significantly. Starvation led to decreased activities of alkaline phosphatase and angiotensin-converting enzyme, but increased activities of mannosidase. Trauma and forced swimming could cause increase of angiotensin-converting enzyme activity and decrease of 5'-nucleotidase activity, respectively. These results indicate that physiological and pathological effects should be excluded from of the above indices as plasma zinc index, in the assessment of body zinc nutrition status.
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PMID:[Effects of stress on indices for assessing zinc nutrition status]. 875 64

We have inactivated the genes encoding components of MntABC, an ABC (ATP binding cassette) transporter system for manganese in the cyanobacterium Synechocystis sp. PCC 6803. The growth rates of these mutant strains were significantly lower in a manganese-deficient medium and were restored to near normal levels upon addition of micromolar concentrations of Mn2+, indicating the presence of a second transport system for manganese in this organism. 54Mn2+ uptake experiments indicated that the MntABC transporter was induced under manganese starvation conditions, whereas the second transporter system was induced in the presence of micromolar levels of manganese. Both of these systems were nonfunctional at low temperatures and could transport trace levels of 54Mn2+, reflecting high affinity active transport. The initial rates of Mn2+ uptake for cells grown with or without manganese exhibited biphasic saturation kinetics, suggesting that Mn2+ can also be accumulated by a low affinity system in these bacteria. The kinetic parameters for the MntABC transporter system are Km = 1-3 microM and Vmax = 3-8 pmol/min.10(8) cells. Accumulation of manganese by this system was competitively inhibited by Cd2+ (Ki = 4-8 microM), Co2+ and Zn2+ (Ki = 8-15 microM). In contrast, the second high affinity system was highly specific for manganese and was not inhibited by any tested metal ion. We have also demonstrated that in this organism, photosynthetic electron transport is necessary for optimal rates of manganese uptake.
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PMID:Manganese transport in the cyanobacterium Synechocystis sp. PCC 6803. 882 46


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