Abstract Body: Introduction: The general population is becoming more obese, and diabetes rates continue to rise, with overnutrition and consumption of processed foods likely contributing factors. Many people consume diets high in fat, sugar, and salt; however, this triad of factors is rarely examined in unison in studies. In addition, studies that examined diets high in fat and sugar in the context of heart failure with preserved ejection fraction and cardiometabolic outcomes have often performed short dietary interventions, with many studies performed in only male mice, and dietary salt content is often not considered or manipulated.
Study Goal: This study aimed to assess the long-term impact of high-fat, high-sucrose diets with differing levels of salt (NaCl) on systemic and cardiovascular physiology in male and female mice.
Methods and results: 12-week-old C57BL/6J male and female mice (n = 4/group) were fed one of the following diets for 25 weeks: normal chow (NC), low-fat diet (LFD; 10 kcal%), high-fat high sucrose (HFHS; 60 kcal%) with 0.33% NaCl, HFHS with 1% NaCl (HFHS1%), and HFHS with 8% NaCl (HFHS8%). Mice were subjected to basal tail blood metabolite assessment and weighed weekly. In week 24, mice were subjected to glucose tolerance testing, dual-energy X-ray absorptiometry followed by postmortem gravimetric, blood metabolite, histological, and biochemical analyses at 25 weeks. We found that irrespective of sex, body weight was significantly greater in mice receiving HFHS (p<0.001) and HFHS1% (p<0.001) versus the other diets. By 25 weeks, male mice were significantly larger than female mice with all diets except HFHS1% (p<0.05), which correlated with increased percent body fat (p<0.01), impaired glucose tolerance (p<0.05) and increased ketone levels (p<0.05) in female mice subjected to HFHS1% versus males on the same diet. There was also increased heart weight and atrial weights in female mice subjected to HFHS and HFHS1% versus the other females, which was not observed in male mice.
Conclusions: Although previous short-term dietary studies have shown that males have altered cardiometabolic responses more than females, our findings together show that long-term dietary interventions with HFHS diets with salt may adversely impact female systemic and cardiovascular physiology.