Gene expression patterns indicate that a high-fat-high-carbohydrate diet causes mitochondrial dysfunction in fish.

Area of Science:

• Aquaculture Nutrition
• Fish Physiology
• Molecular Biology

Background:

• Aquaculture increasingly uses lipids and carbohydrates, replacing fishmeal.
• Excess dietary lipids and carbohydrates negatively impact fish health and nutrient utilization.
• Mechanisms underlying these diet-induced effects in fish remain poorly understood.

Purpose of the Study:

• To investigate the molecular mechanisms of metabolic disorders induced by high-fat, high-carbohydrate diets in blunt snout bream (Megalobrama amblycephala).
• To explore the impact of such diets on liver gene expression and mitochondrial function.
• To assess potential links between diet, liver dysfunction, and neurodegenerative disease pathways in fish.

Main Methods:

• An eight-week feeding trial using a high-fat, high-carbohydrate diet was conducted on blunt snout bream.
• Liver tissue was analyzed using transcriptome sequencing and quantitative PCR (qPCR) to study gene expression changes.
• Differentially expressed genes were mapped to biological pathways and disease categories.

Main Results:

• A high-fat, high-carbohydrate diet significantly altered gene expression in the fish liver.
• Affected genes were disproportionately associated with mitochondrial metabolism, neurodegenerative diseases (Alzheimer's, Huntington's, Parkinson's), and liver dysfunction.
• Evidence suggests potential mitochondrial dysfunction and downregulation of mitochondrial biogenesis in the liver.

Conclusions:

• High-fat, high-carbohydrate diets induce significant molecular changes in fish liver, impacting mitochondrial function.
• The study reveals a novel connection between diet-induced metabolic disorders and neurodegenerative disease pathways in fish.
• Fish models warrant further investigation for understanding diet-associated neurodegenerative disorders relevant to human health.