Microplastics selectively modify ranavirus-driven physiological disruption and gut microbiome restructuring in...

Area of Science:

• Environmental toxicology
• Amphibian physiology
• Microbiome research

Background:

• Amphibians face combined environmental and infectious stressors.
• Microplastics (MPs) and ranavirus (RV) are significant threats.
• Understanding their interactive effects is crucial for amphibian conservation.

Purpose of the Study:

• To investigate the combined effects of MPs and RV on white tree frog physiology and gut microbiome.
• To identify the primary stressor and its interaction with the other.
• To assess the integrated physiological and microbial responses.

Main Methods:

• Utilized a multiblock approach integrating diverse physiological and microbiome endpoints.
• Measured corticosterone (CORT), body condition, serum biochemistry, antioxidant activity, and gut microbiome profiles.
• Analyzed structural changes in the gut microbiome using UniFrac analyses.

Main Results:

• Ranavirus (RV) was the primary driver of physiological disruption, affecting body condition, protein homeostasis, and organ function.
• Microplastics (MPs) directly impacted CORT, bioenergetic budget, and antioxidant defense.
• Increased MP exposure amplified RV viral load, infection rates, and overall physiological harm, altering gut microbiome structure.

Conclusions:

• RV is the principal physiological disruptor in white tree frogs.
• MPs act as a modifier, exacerbating RV-induced responses and increasing physiological disruption.
• These combined stressors pose a hidden cost, elevating ecological risk for amphibians.