High Fat Diet Impacts Gut Microbiome Differently in Male and Female Sprague Dawley Rats

Abstract

Obesity has increased during the last couple of decades and is strongly related to cardiovascular disease, hyperlipidemia, diabetes, and neurological disorders, such as depression, which tend to be more prevalent in women. A high fat diet (HFD) is associated with negative effects on the gut microbiome, including increased Firmicutes/Bacteriodetes ratio (F/B ratio) which may affect the integrity of the intestinal barrier. Gut microbiome transplants from male to female rats have been shown to decrease diabetes type 1 in females, suggesting sex differences in the gut microbiome. Previous studies in our lab have shown that Sprague Dawley male rats fed with a HFD showed a depressive‐like behavior and also a decrease of tight junction proteins in the gut suggesting gut permeability. However, it is not clear whether the effects of a HFD on the microbiome are based on gender differences.AIMTo ascertain whether the administration of a HFD will affect differently the gut microbiome in males and females.METHODSThere were four groups of Sprague Dawley rats (n=12/group): Female Low‐Fat Diet (FLFD), Female High Fat Diet (FHFD), Male Low‐Fat Diet (MLFD), Male High Fat Diet (MHFD). Female and male postnatal rats were fed with a LFD (10% fat) for 6 weeks. Then, half of each group were transferred to a HFD (60% fat) for 8 weeks. We measured absolute weight daily, and rats were tested for depressive like syndrome in a porsolt swim test one day before sacrifice. Fat and feces were collected from all animals to assess differences in the gut microbiome.RESULTSRats showed no differences in absolute weight nor in percent weight gain in either group, however, MHFD showed an increase of epidydimal fat tissue compared to MLFD. FHFD group showed a significant increase in immobility compared with the FLFD group suggesting depressive like syndrome (p<0.05). Measurement of depressive like syndrome in males was limited by their size and did not reach significance. In gut microbiome, MHFD showed a significant increase in the F/B ratio compared with the MLFD, however, in females there were no significant differences. Females on a high‐fat diet had a significant increase in Proteobacteria compared to FLFD (p<0.05). In contrast MHFD showed a significant increase in Verrucomicrobia compared with the MLFD (p<0.05).CONCLUSIONSA HFD affects the gut microbiome of males and females differently. The significance of this study is that sex differences may be a potential factor in how a HFD might contribute towards various pathophysiological conditions via differing effects on the gut microbiome.Support or Funding InformationSupported by NIGMS/INBRE P20 GM103475‐14 and RCMI G12 MD007579This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.