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)

The objective of these studies was to determine how alterations in dietary carbohydrate affect hepatic glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH) and malic enzyme (ME) activities in adult female rats. Rats were either starved 2 d and then refed a nonpurified diet or a purified 65% carbohydrate diet (glucose, sucrose, fructose or cornstarch) for 3 d, or switched from nonpurified to purified diets for 3 d. Liver G6PDH, 6PGDH and ME activities were determined. In males, enzyme activities were 8- to 12-fold and 3-fold higher when starved and refed purified diets and nonpurified diets, respectively, whereas in females, activities were 2- to 3-fold higher only when refed purified diets. Both genders had higher enzyme activities when shifted to purified diets. Females responded less dramatically than males. Of the higher enzyme activities observed during starvation-refeeding studies, in females 58-65% of the change is a function of switching rats from nonpurified to purified diets. In contrast, in males only 24-40% of the higher activities could be attributed to diet shifting. Results of these studies indicate that the effects of dietary carbohydrates on hepatic G6PDH, 6PGDH and ME activities are gender dependent.
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PMID:Gender-linked differences in dietary induction of hepatic glucose-6 phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and malic enzyme in the rat. 376 Oct 10

Adult female Sprague-Dawley rats were either prefed ground nonpurified diet, starved 48 h, then refed a purified carbohydrate diet for 72 h or shifted from ground nonpurified diet directly to a purified carbohydrate diet for 72 h. Diets were formulated to contain 65% carbohydrate either as the disaccharides maltose or sucrose or as their respective monosaccharide equivalents glucose and invert sugar (glucose: fructose, 1:1). Alternations in hepatic glucose 6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH) and malic enzyme (ME) activities, relative liver size and food efficiency were determined. Rats starved and refed invert sugar had higher levels of G6PDH and ME than those red glucose, indicating a positive fructose effect. The greatest changes in hepatic enzyme activities were observed in rats consuming diets containing sucrose. Positive fructose and disaccharide effects were obtained with sucrose for all enzymes studied in both dietary shift and starve-refeed studies. No disaccharide effect was observed with maltose. In conclusion, females did not display a generalized disaccharide effect with either dietary shifting or starvation refeeding.
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PMID:Absence of a generalized disaccharide effect in adult female rats. 376 Oct 11

The interacting effects of thyroid hormone, age, and duration of starvation on the enzyme and liver lipid responses of BHE rats to starvation-refeeding were studied. Rats were starved for 2, 4, or 7 days and refed a 65% glucose diet for 2 days. The rats were either 150 or 420 days of age and injected daily with either saline or 10 micrograms thyroxine/100 g body weight. Neither age nor duration of starvation affected the glucose-6-phosphate dehydrogenase or malic enzyme activity or liver lipid response to starvation-refeeding. However, thyroxine treatment potentiated the response to starvation-refeeding in the 420-day-old rats when the duration of starvation increased from 2 to 7 days.
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PMID:Age and thyroid hormone as factors in the responses of BHE rats to starvation-refeeding. 376 98

Responses of the hepatic lipogenic enzymes, glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), and malic enzyme (ME) to starvation refeeding and diet shifting were determined in lean and obese female Zucker rats. Rats were either fed nonpurified diet, starved 48 hr, and then refed nonpurified diet or one of the refined carbohydrate diets containing either glucose, fructose, cornstarch, or sucrose for 72 hr, or shifted from nonpurified diet directly to one of the refined carbohydrate diets for 72 hr. Initial activities were greater in obese than lean rats for all three enzymes studied. Similar to other strains of female rats, lean Zucker rats failed to demonstrate a starve-refeed response when refed nonpurified diet. Obese female littermates showed a statistically significant increase in enzymes when refed a nonpurified diet. Both lean and obese female Zucker rats demonstrated increases in enzyme activities above controls when starved and refed any of the refined carbohydrate diets. The greatest responses were observed when female rats were starved and refed sucrose; activities increased 2.6- to 3.5-fold in lean and 3.0- to 4.3-fold in obese Zuckers. In lean females 50-70% of the starve-refeed response observed with G6PDH and ME can be accounted for by simply shifting from a nonpurified diet to the respective refined carbohydrate diet, whereas in obese females only 33-55% of the increase could be attributed to diet shifting. Plasma testosterone/estrogen ratios were consistently 1.5 times higher in obese than in lean female rats. This phenotypic difference may potentiate the heightened starve-refeed overshoot response observed in obese rats.
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PMID:Dietary induction of hepatic glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and malic enzyme in lean and obese female Zucker rats. 382 5

Insulin treatment of virgin female rats increased the hepatic activity of glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase to levels 3.4 and 1.5 fold higher than controls. The increase in glucose 6-phosphate dehydrogenase activity was attributed to increased activity of all three dimer species. Thus dimer bands, 1, 2 and 3 of insulin-treated animals were 5, 3 and 2-fold higher respectively than controls. The activity of glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase decreased with fasting to 55% and 72% respectively of controls. The decrease in glucose 6-phosphate dehydrogenase activity reflected a lower activity of dimer bands 2 and 3 only, which were 62% and 39% of control activity respectively after three days fasting. A shift towards band 1 was observed under both conditions of starvation as well as under conditions of insulin treatment.
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PMID:Regulation of the multiple molecular forms of rat liver glucose 6-phosphate dehydrogenase by insulin and dietary restriction. 388 6

The interacting effects of sucrose or starch with corn or coconut oil on the lipogenic responses of rats to starvation-refeeding was studied. Rats were either ad libitum-fed or starved for 48 h and refed for 48 h. Four different diets were used: 65% starch-5% corn oil, 65% starch-5% coconut oil, 65% sucrose-5% corn oil, 65% sucrose-5% coconut oil. Lipogenesis was assessed in two ways: glucose-6-phosphate dehydrogenase (G6PD) activity, malic enzyme (ME) activity and percent liver lipid (expt 1) and tritium (3HOH) incorporation into fatty acids (expt 2). Starved-refed rats had more liver lipid, greater enzyme activity and greater 3H incorporation into fatty acids than ad libitum-fed rats. Sucrose-fed rats had more lipogenic activity than starch-fed rats. Rats fed coconut oil were more lipogenic than rats fed corn oil. There were highly significant correlation coefficients between the enzyme activities (G6PD and ME) and the percent liver lipid and between the enzyme activities and 3H incorporation into fatty acid. Analysis of variance of these data revealed significant dietary effects on these lipogenic responses to starvation-refeeding. We conclude that both dietary carbohydrate and lipid play a significant role in the determination of the magnitude of the lipogenic response to starvation-refeeding.
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PMID:Effect on the interaction of dietary carbohydrate and fat on the responses of rats to starvation-refeeding. 396 62

1. Lactic acid formation in supernatant fractions of homogenates of cat or rat small-intestinal mucosa was measured under optimum conditions with glucose, fructose, glucose 6-phosphate, fructose 1,6-diphosphate or 3-phosphoglycerate as substrate. 2. Between 80 and 107% of the glycolytic activity of the homogenate was recovered in these particle-free preparations when glucose, fructose, glucose 6-phosphate or fructose 1,6-diphosphate was used as substrate. 3. Evidence was obtained that hexokinase and phosphofructokinase were the rate-limiting enzymes in the initial sequence of glycolytic reactions. The limitation of rate by hexokinase was much more pronounced in preparations from the cat than in those from the rat. 4. With subcellular preparations from cat or rat small intestine lactic acid was also formed from ribose 5-phosphate and at rates similar to those observed with glucose. 5. A higher rate of glycolysis was observed with glucose 6-phosphate as substrate with preparations from the proximal half of the small intestine of the rat as compared with the distal half. 6. Mucosal preparations from rats starved for 24-48hr. exhibited only about one-quarter of the glycolytic activity of those of fed control groups. The decreased rate of formation of lactic acid from either glucose or fructose was mainly due to a decrease in the activity of hexokinase(s). The activities of glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase and a number of other enzymes were not significantly decreased by starvation. 7. The results are discussed in relation to metabolic control of glycolysis in other mammalian tissues.
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PMID:Glucose metabolism in the mucosa of the small intestine. Glycolysis in subcellular preparations from the cat and rat. 429 Sep 84

1. Optimum conditions were established for determining the activities of the NADP(+)-linked enzymes, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and isocitrate dehydrogenase, in mosquito tissues. 2. The activity of each dehydrogenase was determined in samples of mosquitoes of different ages throughout the life-span. The specific-activity curves attained maximal values in the pupal or early adult period. From these maxima an 81% decrease in glucose 6-phosphate-dehydrogenase and 67% decrease in 6-phosphogluconate-dehydrogenase activities occurred after the tenth day of adult life; a 77% decrease in isocitrate-dehydrogenase activity occurred before the fifth day. 3. The activity differences were found in different body regions as well as in whole organisms. 4. Starvation of the larva or adult did not result in decreases in enzyme activity. 5. These findings support the hypothesis that the activities of enzymes that form NADPH are related to the biosynthetic activity, for the enzyme activities increased during the period of cellular growth and decreased during the aging period.
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PMID:Nicotinamide-adenine dinucleotide phosphate enzymes in the mosquito during growth and aging. 438 47

1. The degradation rates and half-lives of hexokinase, 6-phosphogluconate dehydrogenase, lactate dehydrogenase, pyruvate kinase, glucose 6-phosphate dehydrogenase, phosphoglycerate kinase and aldolase were calculated from measurements of the decline in activities of these enzymes in rat small intestine during starvation. 2. The half-lives of the enzymes are: hexokinase, 5.7h; 6-phosphogluconate dehydrogenase, 7.6h; glucose 6-phosphate dehydrogenase, 6.0h; pyruvate kinase, 8.9h; lactate dehydrogenase, 8.7h; phosphoglycerate kinase, 8.7h; aldolase, 5.1h. 3. The significance of the results is discussed with respect to the regulation of enzyme concentrations in response to changes in diet.
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PMID:Degradation of glucose-metabolizing enzymes in the rat small intestine during starvation. 472 2

Activity of glucose-6-phosphate dehydrogenase in haematopoietic cells of bone marrow of rabbits was not affected during insular deficiency induced by starvation or alloxan diabetes as well as after intramuscular hydrocortisone administration. It is suggested that slight decrease in the activity of hexokinase detected during starvation and hydrocortisone administration might be accounted for by the presence of mature leukocytes in the population of isolated myelokaryocytes.
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PMID:[Activity of hexokinase and glucose-6-phosphate dehydrogenase in hemopoietic cells of the bone marrow in normal rabbits and after hydrocortisone administration during starvation and alloxan diabetes]. 531 22


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