TOPLINE:

In a rat model of metabolic dysfunction-associated steatotic liver disease (MASLD), both vitamin D supplementation and intermittent fasting (IF) improved multiple metabolic and liver measures, including blood sugar control, lipid levels, liver injury, oxidative stress, and liver fat and inflammation, with IF producing stronger effects in some areas.

METHODOLOGY:

• Lifestyle and nutritional interventions have recently gained attention as nonpharmacologic approaches to MASLD management.
• Researchers conducted an experiment in male Sprague-Dawley rats, which have feeding behaviors similar to humans, to assess therapeutic effects of vitamin D supplementation and IF on MASLD.
• MASLD was induced by feeding a high-fat and fructose diet (HFD) having 45% fat with 20% fructose for 12 weeks, followed by a 4-week intervention period.
• A total of 24 rats aged 12-14 weeks were randomly assigned to one of the following four groups: a control group given a standard diet, an HFD group, an HFD plus vitamin D group that received 5 µg/kg vitamin D injections every 2 days, and an HFD plus IF group that alternated 24 hours of feeding with 24 hours of fasting.
• Researchers measured body weight, blood glucose and insulin levels, liver function, lipid profile, inflammatory markers, and oxidative stress markers and examined liver tissue to assess changes at the end of the study.

TAKEAWAY:

• Rats in the HFD group developed marked metabolic and liver injury, including elevated liver enzymes, hyperglycemia, abnormal lipids, oxidative stress, and extensive liver fat compared with control rats.
• Both the vitamin D and IF groups had reduced blood glucose levels (~52% and 55%, respectively) and increased serum insulin levels (~53% and 60%, respectively) compared with the HFD group (P < .05 for all). Both groups also had lowered triglyceride and low-density lipoprotein cholesterol levels — more with IF — and modestly increased high-density lipoprotein cholesterol levels (P < .05 for all).
• Both the vitamin D and IF groups had reduced levels of alanine aminotransferase (~36% and 30%, respectively), aspartate aminotransferase (~32% and 36%, respectively), and malondialdehyde (~32% and 41%, respectively), with increased levels of reduced glutathione (~64% and 96%, respectively) compared with the HFD group (P < .05 for all).
• Liver tissue showed less fat and inflammation with both interventions, with reduced expression of sterol regulatory element-binding protein 1 and lower inflammatory signaling compared with HFD.

IN PRACTICE:

“[The study] results highlight the potential utility of vitamin D and intermittent fasting as complementary, nonpharmacological strategies for MASLD management and underscore the need for future clinical studies to evaluate their therapeutic effectiveness in human populations,” the authors of the study wrote.

SOURCE:

The study was led by Ola Mohammed Youssef, MD, Mansoura University, Mansoura, Egypt. It was published online in Scientific Reports.

LIMITATIONS:

The study duration was relatively short and may not have captured long-term liver changes such as fibrosis. Only male rats were studied, limiting assessment of sex-specific differences. The absence of transcriptomic or metabolomic analyses restricted deeper mechanistic insights.

DISCLOSURES:

The study received funding from the Department of Basic Medical and Dental Sciences, Faculty of Dentistry, Zarqa University, Zarqa, Jordan. The authors declared having no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.