Long-term high-fat-diet feeding impairs mitochondrial biogenesis in liver of male and female rats.
OBJECTIVE
Mitochondrial biogenesis includes both mitochondrial proliferation and differentiation and its regulation under different physiological conditions is not clear. Given the sexual dimorphism previously found in mitochondrial function, the aim of this study was to investigate the gender-dependent effect of chronic high-fat-diet (HFD) feeding on rat liver mitochondrial function and biogenesis.


METHODS
Ten-week old male and female rats were fed a HFD (26% fat) or a control diet (2.9% fat) for 26 weeks. Mitochondrial morphology was studied. Mitochondrial DNA and protein content, hydrogen peroxide production, oxidative capacity, antioxidant defenses, as well as markers of oxidative damage and mitochondrial biogenesis were analyzed.


RESULTS
Female rats showed higher levels of mitochondrial protein and an enhanced oxidative capacity per mitochondrion than males. In both genders, HFD feeding increased mtDNA content and decreased mitochondrial differentiation markers.


CONCLUSIONS
In comparison to male rats, females show higher oxidative capacity as a consequence of their greater mitochondrial differentiation under both control and obese status. In response to HFD feeding, the oxidative capacity of the whole mitochondrial population is maintained in both genders. This is obtained by means of an enhancement of mitochondrial proliferation, which counteracts the diet-induced impairment of the function of each mitochondrion.
Nadal-Casellas
Antònia
A
Grup de Metabolisme Energètic i Nutrició, Departament de Biologia Fonamental i Ciències de la Salut, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Spain.
Amengual-Cladera
Emilia
E
Proenza
Ana María
AM
Lladó
Isabel
I
Gianotti
Magdalena
M
D000818:Animals; D002950:Citrate (si)-Synthase / Q000378:metabolism; D004041:Dietary Fats / Q000494:pharmacology; D003576:Electron Transport Complex IV / Q000378:metabolism; D004958:Estradiol / Q000097:blood; D005260:Female; D005979:Glutathione Peroxidase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism*; D018384:Oxidative Stress; D051381:Rats; D017208:Rats, Wistar; D012737:Sex Factors; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors
D004041:Dietary Fats; D004958:Estradiol; D006861:Hydrogen Peroxide; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D003576:Electron Transport Complex IV; D002950:Citrate (si)-Synthase