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)

Clinical observations suggest that overt rhabdomyolysis may occur if severe hypophosphatemia is superimposed upon a pre-existing subclinical myopathy. To examine this possibility, a subclinical muscle cell injury was induced in 23 dogs by feeding them a phosphorus- and calorie-deficient diet until they lost 30% of their original weight. To induce acute, severe hypophosphatemia in the animals after partial starvation, 17 of the dogs were given large quantities of the same phosphorus-deficient diet in conjunction with an oral carbohydrate supplement, which together provided 140 kcal/kg per day. After phosphorus and caloric deprivation, serum phosphorus and creatine phosphokinase (CPK) activity were normal. Total muscle phosphorus content fell from 28.0+/-1.3 to 26.1+/-2.5 mmol/dg fat-free dry solids. Sodium, chloride, and water contents rose. These changes resembled those observed in patients with subclinical alcoholic myopathy. When studied after 3 days of hyperalimentation, the animals not receiving phosphorus showed weakness, tremulousness, and in some cases, seizures. Serum phosphorus fell, the average lowest value was 0.8 mg/dl (P <0.001). CPK activity rose from 66+/-357 to 695+/-1,288 IU/liter (P <0.001). Muscle phosphorus content fell further to 21.1+/-7.7 mmol/dg fat-free dry solids (P <0.001). Muscle Na and Cl contents became higher (P <0.01). Sections of gracilis muscle showed frank rhabdomyolysis.6 of the 23 phosphorus- and calorie-deprived dogs were also given 140 kal/kg per day but in addition, each received 147 mmol of elemental phosphorus. These dogs consumed their diet avidly and displayed no symptoms. They did not become hypophosphatemic, their CPK remained normal, and derangements of cellular Na, Cl, and H(2)O were rapidly corrected. The gracilis muscle appeared normal histologically in these animals. These data suggest that a subclinical myopathy may set the stage for rhabdomyolysis if acute, severe hypophosphatemia is superimposed. Neither acute hypophosphatemia nor rhabdomyolysis occur if abundant phosphorus is provided during hyperalimentation.
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PMID:Hypophosphatemia and rhabdomyolysis. 74 77

Alcoholic myopathy occurs in up to two thirds of alcohol misusers and is characterized by selective atrophy of type II (anaerobic, fast-twitch) fibers; type I (aerobic, slow twitch) fibers are relatively unaffected. Both clinical and animal studies have indicated that skeletal muscle RNA content is reduced in response to ethanol exposure, and contributes to impaired protein synthesis. We hypothesized that the reduction in muscle RNA may be due to raised ribonuclease (RNase) activities that enhance RNA catabolism. To test this hypothesis, we measured the total tissue and plasma RNase activities as well as the activities of general (RNase A) and specific or "restriction" RNases (T1L, T2L) in ethanol-treated rats. Chronically treated rats were fed a nutritionally complete liquid diet with 35% of calories as ethanol. Weight-matched controls were pair-fed with isocaloric glucose. Rats were killed at time-points up to 6 weeks. For comparative purposes, the effect of acute (24 hr) starvation was also analyzed in a second group of rats relative to a group of control rats allowed free access to food and water over 24 hr. Results showed that the type II fiber-predominant plantaris muscle exhibited a significant increase in total RNase, RNase A and RNase T1L activities (increases ranged from +59% to +196%; P-values between 0.025 and 0.01) concomitant with large falls in RNA and protein content. In contrast, none of the RNase activities measured in the type I fiber-predominant soleus muscles were significantly affected; compositional changes were also smaller in the soleus. This effect was independent of reduced nutrition. In conclusion, the raised total RNase, RNase A and RNase T1L activities may contribute to the type II fiber-specific reduction in total RNA in chronically ethanol-treated rats. In turn, this may contribute to the alterations in cellular protein metabolism seen under these treatments.
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PMID:Skeletal muscle ribonuclease activities in chronically ethanol-treated rats. 966 Mar 15

Alcoholic myopathy is a common pathology characterized by wasting due to reduced protein synthesis, although the mechanisms involved remain unclear. Women are particularly sensitive and malnutrition exacerbates the myopathy. This study aimed to address (i) whether long-term alcohol feeding alters expression of heat shock proteins (HSPs) in male and female rats; (ii) the effect of immediate alcohol dosing with or without raised levels of endogenous acetaldehyde; and (iii) the effect of starvation. To address this, (i) male and female rats were fed alcohol in the long-term (6-7 weeks as 35% of energy in a liquid diet) and compared to controls fed the same diet with isoenergetic glucose; (ii) male rats given an immediate bolus (75 mmol ethanol per kilogram body weight intraperitoneally) 2.5 hours before sacrifice and compared to controls given a dose of saline (with or without pretreatment with cyanamide-an acetaldehyde dehydrogenase inhibitor which raises endogenous acetaldehyde); (iii) male rats starved for 1 or 2 days then immediately dosed with alcohol. Protein levels of HSP 27, HSP 60, and HSP 70 were measured in muscles of male rats fed alcohol and pair-fed control rats by SDS-PAGE and Western blotting in study I. Levels of HSP 27, HSP 60, HSP 70, and HSP 90 mRNA were analyzed in hind limb skeletal muscle by reverse transcription-polymerase chain reaction with an endogenous internal standard, glyceraldehyde-3-phosphate-dehydrogenase. (i) Long-term alcohol dosage reduced HSP 27 in male rats but not in females, whereas HSP 90 mRNA increased in long-term alcohol-fed female rats but not in male rats. These changes were reflected by a similar trend in HSP protein content, although statistical significance was not achieved. (ii) There was no effect on any of the HSP mRNAs in rats dosed immediately with alcohol or in combination with cyanamide. (iii) Starvation per se for 2 days was associated with an increase in HSP 27 mRNA. Alcohol administration after 2 days starvation caused a blunting of the increased HSP 27 mRNA in starvation alone. This suggests that long-term alcohol exposure affects HSP gene expression and that this effect is moderated by sex and starvation. This may contribute to, or reflect, the biochemical lesion in alcoholic myopathy.
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PMID:Alcohol alters skeletal muscle heat shock protein gene expression in rats: these effects are moderated by sex, raised endogenous acetaldehyde, and starvation. 1678 54