# Vitamin D modulates gene expression in four major muscle tissues in Atlantic salmon

## TL;DR

Vitamin D affects gene expression in different muscle tissues of Atlantic salmon, with notable changes in the heart.

## Contribution

The study reveals how vitamin D influences gene expression in multiple muscle types and highlights conserved responses across vertebrates.

## Key findings

- Vitamin D had a strong effect on gene expression in the heart muscle of salmon.
- Five genes were differentially expressed across multiple muscle types.
- Many vitamin D-affected genes in salmon are conserved in mammals, including humans.

## Abstract

Vitamin D is essential to muscle health but could affect different muscle tissues in distinct ways. In humans, vitamin D is primarily synthesized in the skin via sun exposure but can also be obtained through ingesting foods that are fortified (e.g., milk) or naturally high in vitamin D (e.g., salmon). Like humans, salmon vitamin D content can vary considerably and can be altered through dietary consumption of vitamin D. We experimentally determined how vitamin D manipulation alters gene expression in four salmon muscle tissues: skeletal, craniofacial, smooth, and cardiac. Vitamin D induced changes in expression were exceptionally profound in the heart, where there were also several gene duplicates expressed unidirectionally. Five genes were differentially expressed in multiple muscles and many genes impacted by our vitamin D treatments in salmon show extensive evolutionary conservation as they are influenced by vitamin D titers in mammals, including humans. Salmon could provide a powerful model for understanding how variation in vitamin D impacts all vertebrates.

The online version contains supplementary material available at 10.1038/s41598-025-22850-1.