Impairment of energy metabolism and increase of free radicals production play a major role in agerelated apoptotic loss of cardiomyocites. Since recent reports have shown that ketone bodies increase cardiac metabolic efficiency and exert cardio-protective antioxidant effects, we investigated the consequences of a medium chain triglycerides ketogenic diet (MCT-KD) on the aging heart of late-adult (19 month-old) rats. After 8-week MCT-KD feeding, the activity of succinic dehydrogenase (SDH) was cytochemically evidenced in cardiomyocites by the copper ferrocyanide method. Young (5 month-old), age-matched (19 month-old) and old (27 month-old) animals fed with a standard chow were sed as controls. The overall area of the precipitates due to SDH activity (PA) and the area of the SDH-positive mitochondria (MA) were measured. The percent ratios MA/total myocardial tissue area (MA/TA) and PA/MA were the parameters taken into account. We found that both parameters were significantly higher in MCT-KD fed rats vs. age-matched and old controls; PA/MA was significantly higher in young controls vs. late-adult MCT-KD fed and control animals, and both parameters were significantly higher in young vs. old controls. These data indicate that 8-week MCT-KD administration partially recovers the age-related decrease of SDH activity and increases the myocardial area occupied by metabolically active mitochondria. SDH is one of the most reliable markers of the mitochondrial capability to provide adequate amount of ATP, as it is part of both the Krebs cycle and the respiratory chain. Moreover, because of its unique redox properties, SDH provides a major contribution to the reduction of the ubiquinone pool, important antioxidant reservoir in the inner membrane of the organelles. Therefore, these findings suggest that MCT-KD may improve cardiac energetic efficiency, confirming and extending previous results obtained in the working perfused rat myocardium. The use of this diet might counteract typical alterations of the aging heart, which play a primary role in apoptotic-triggered myocardial atrophy.
The potential role of a ketogenic diet on the age-related apoptotic loss of cardiomyocites / Balietti M.; Fattoretti P.; Giorgetti B.; Casoli T.; Di Stefano G.; Solazzi M.; Platano D.; Aicardi G.; Bertoni-Freddari C.. - ELETTRONICO. - (2008), pp. 215-215. (Intervento presentato al convegno Apoptosis World 2008 From mechanisms to applications tenutosi a Luxembourg nel January 23-26, 2008).
The potential role of a ketogenic diet on the age-related apoptotic loss of cardiomyocites.
AICARDI, GIORGIO;
2008
Abstract
Impairment of energy metabolism and increase of free radicals production play a major role in agerelated apoptotic loss of cardiomyocites. Since recent reports have shown that ketone bodies increase cardiac metabolic efficiency and exert cardio-protective antioxidant effects, we investigated the consequences of a medium chain triglycerides ketogenic diet (MCT-KD) on the aging heart of late-adult (19 month-old) rats. After 8-week MCT-KD feeding, the activity of succinic dehydrogenase (SDH) was cytochemically evidenced in cardiomyocites by the copper ferrocyanide method. Young (5 month-old), age-matched (19 month-old) and old (27 month-old) animals fed with a standard chow were sed as controls. The overall area of the precipitates due to SDH activity (PA) and the area of the SDH-positive mitochondria (MA) were measured. The percent ratios MA/total myocardial tissue area (MA/TA) and PA/MA were the parameters taken into account. We found that both parameters were significantly higher in MCT-KD fed rats vs. age-matched and old controls; PA/MA was significantly higher in young controls vs. late-adult MCT-KD fed and control animals, and both parameters were significantly higher in young vs. old controls. These data indicate that 8-week MCT-KD administration partially recovers the age-related decrease of SDH activity and increases the myocardial area occupied by metabolically active mitochondria. SDH is one of the most reliable markers of the mitochondrial capability to provide adequate amount of ATP, as it is part of both the Krebs cycle and the respiratory chain. Moreover, because of its unique redox properties, SDH provides a major contribution to the reduction of the ubiquinone pool, important antioxidant reservoir in the inner membrane of the organelles. Therefore, these findings suggest that MCT-KD may improve cardiac energetic efficiency, confirming and extending previous results obtained in the working perfused rat myocardium. The use of this diet might counteract typical alterations of the aging heart, which play a primary role in apoptotic-triggered myocardial atrophy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
