A-49 Free Communication/Poster - Nutrition Interventions Wednesday, May 30, 2018, 7:30 AM - 12:30 PM Room: CC-Hall B
PURPOSE: Ketogenic Diets (KD) consist of high fat, moderate protein and low carbohydrate. KD have been used as a weight loss tool and as a therapeutic tool for neurological disorders. It has been suggested that KD increase longevity, but to date only two studies in mice have been performed with equivocal results. Therefore, we determined the effects of KD on longevity and multi-organ oxidative stress markers in rats.
METHODS: Ten month-old male Sprague-Dawley rats (n=8 per group) were provided with one of two isocaloric diets: standard chow (SC; 24% (% kcal) protein, 58% CHO, 18% fat; 20 g/day) or KD (23% protein, 10% carbohydrate, 67% fat; 16 g/day). Rats were euthanized if: a) vitality scores (range = 4 (good health) to 20 (poor health)) exceeded a score of 16 per the recommendations of Phillips et al. (J Am Assoc Lab Anim Sci, 2010, 49(6): 792- 799), b) rapid weight loss accompanied by changes in food and water consumption, or c) the rat suffered from a condition to which a university veterinarian deemed euthanasia necessary for humane purposes. Upon euthanasia, the gastrocnemius muscle, liver, and brain were removed and stored at -80°C and analyzed for markers of oxidative damage (4-hydroxynonenal (4HNE) and protein carbonyls (Oxyblot)) and protein levels of the antioxidants superoxide dismutase 1/2 (SOD1/2), catalase (CAT), and glutathione peroxidase (GPX).
RESULTS: The survivability log-rank test indicates that KD increased the lifespan of rats (p=0.009) when compared to SC. No significant difference in body mass was observed at the beginning (SC=425.7±13.2, KD=435.9±5.8) or end (SC=428.0±25.4, KD=417.1±22.6) of the experiment, and liver and gastrocnemius mass at sacrifice was not significantly different between groups (p>0.05). Liver CAT protein levels were about 30% higher in KD, albeit not significant (p=0.062). Additionally, liver SOD1 protein levels were about 20% higher in KD, but again, this was not significant (p=0.094). No other significant differences in protein levels of antioxidants, 4HNE, or Oxyblot were observed in either the gastrocnemius, liver, or brain.
CONCLUSIONS: Lifelong KD improves longevity in rats without altering body mass and our data show that the longevity benefits of KD come without altering oxidative damage or antioxidant protein levels in the gastrocnemius, liver, or brain.