- Liittynyt
- 7.10.2002
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Joki aiemmin kyseli glutamiinin mahd. hyödyistä kortikosteroidihoidon aikana.. just tuli ulos julkaisu kreatiinista:
J Appl Physiol (October 19, 2006). doi:10.1152/japplphysiol.01188.2005
Submitted on September 17, 2005
Accepted on October 17, 2006
Creatine supplementation attenuates corticosteroid-induced muscle wasting, and impairment of exercise performance in rats
Luciana Menezes1, Claudia Sobreira2, Luciano Neder3, Antonio Luis Rodrigues Junior4, and Jose A. Baddini Martinez5* 1 Department of Internal Medicine, Medical School of Ribeirao Preto - University of Sao Paulo, Ribeirao Preto, São Paulo, Brazil
2 Department of Neurology, Psychiatry and Medical Psychology, Medical School of Ribeirao Preto - University of Sao Paulo, Ribeirao Preto , São Paulo, Brazil
3 Department of Pathology, Medical School of Ribeirao Preto, Ribeirao Preto, São Paulo, Brazil
4 Social Medicine Department, Medical School of Ribeirao Preto-University of Sao Paulo, Ribeirao Preto, SP, Brazil
5 Department of Internal Medicine, Medical School of Ribeirão Preto-University of São Paulo, Ribeirao Preto, Sao Paulo, Brazil
* To whom correspondence should be addressed. E-mail: jabmarti@fmrp.usp.br .
The present study investigated whether creatine (Cr) could attenuate the deleterious effects of high doses of dexamethasone (Dexa) on body mass, exercise performance and respiratory variables of rodents. Forty-four Wistar rats performed incremental maximal exercise tests. They were then assigned to four groups: G1: subcutaneous (SC) and intraperitoneal (IP) saline; G2: SC saline and IP Cr (250 mg/kg/day); G3: SC Dexa (7.5 mg/kg/day) and IP saline; G4: SC Dexa and IP Cr. New exercise tests and analysis of the respiratory pattern under resting conditions and after stimulation with doxapram (2 mg/kg IP) were performed after 18 days. Post- minus pre-treatment differences were compared between groups. G3 and G4 showed a significant impairment in body mass gain compared to G1 and G2 (p<0.05); (G1: 65.3 ± 26.1 X G2: 93.1 ± 27.4 X G3: -18.4 ± 20.1 X 9.8 ± 23.1 kg.10-3). Similar results were observed for maximal oxygen consumption (G1: 9.5 ±8.5 X G2: 25.8 ± 14.5 X G3: -25.5 ± 6.0 X G4: -4.8 ± 9.5 ml/kg/min) and test duration (G1: 43.0 ± 45.0 X G2: 72.0 ± 59.5 X -165.0 ± 60.6 X -48.0 ± 48.5 s). Simultaneous use of Cr significantly attenuated the Dexa-induced impairment of the last two variables. Cr attenuated Dexa-induced gastrocnemius and diaphragm muscle weight losses and the atrophy of gastrocnemius type IIb fibers. Cr supplementation had only small effects on Dexa-induced respiratory changes. These results suggest that Cr may play a role in the prophylaxis or treatment of steroid-induced myopathy.
J Appl Physiol (October 19, 2006). doi:10.1152/japplphysiol.01188.2005
Submitted on September 17, 2005
Accepted on October 17, 2006
Creatine supplementation attenuates corticosteroid-induced muscle wasting, and impairment of exercise performance in rats
Luciana Menezes1, Claudia Sobreira2, Luciano Neder3, Antonio Luis Rodrigues Junior4, and Jose A. Baddini Martinez5* 1 Department of Internal Medicine, Medical School of Ribeirao Preto - University of Sao Paulo, Ribeirao Preto, São Paulo, Brazil
2 Department of Neurology, Psychiatry and Medical Psychology, Medical School of Ribeirao Preto - University of Sao Paulo, Ribeirao Preto , São Paulo, Brazil
3 Department of Pathology, Medical School of Ribeirao Preto, Ribeirao Preto, São Paulo, Brazil
4 Social Medicine Department, Medical School of Ribeirao Preto-University of Sao Paulo, Ribeirao Preto, SP, Brazil
5 Department of Internal Medicine, Medical School of Ribeirão Preto-University of São Paulo, Ribeirao Preto, Sao Paulo, Brazil
* To whom correspondence should be addressed. E-mail: jabmarti@fmrp.usp.br .
The present study investigated whether creatine (Cr) could attenuate the deleterious effects of high doses of dexamethasone (Dexa) on body mass, exercise performance and respiratory variables of rodents. Forty-four Wistar rats performed incremental maximal exercise tests. They were then assigned to four groups: G1: subcutaneous (SC) and intraperitoneal (IP) saline; G2: SC saline and IP Cr (250 mg/kg/day); G3: SC Dexa (7.5 mg/kg/day) and IP saline; G4: SC Dexa and IP Cr. New exercise tests and analysis of the respiratory pattern under resting conditions and after stimulation with doxapram (2 mg/kg IP) were performed after 18 days. Post- minus pre-treatment differences were compared between groups. G3 and G4 showed a significant impairment in body mass gain compared to G1 and G2 (p<0.05); (G1: 65.3 ± 26.1 X G2: 93.1 ± 27.4 X G3: -18.4 ± 20.1 X 9.8 ± 23.1 kg.10-3). Similar results were observed for maximal oxygen consumption (G1: 9.5 ±8.5 X G2: 25.8 ± 14.5 X G3: -25.5 ± 6.0 X G4: -4.8 ± 9.5 ml/kg/min) and test duration (G1: 43.0 ± 45.0 X G2: 72.0 ± 59.5 X -165.0 ± 60.6 X -48.0 ± 48.5 s). Simultaneous use of Cr significantly attenuated the Dexa-induced impairment of the last two variables. Cr attenuated Dexa-induced gastrocnemius and diaphragm muscle weight losses and the atrophy of gastrocnemius type IIb fibers. Cr supplementation had only small effects on Dexa-induced respiratory changes. These results suggest that Cr may play a role in the prophylaxis or treatment of steroid-induced myopathy.
