Zebrafish Bone and General Physiology Are Differently Affected by Hormones or Changes in Gravity

Area of Science:

• * Developmental biology
• * Physiology
• * Genomics

Background:

• * Teleost fish, like zebrafish (Danio rerio), are valuable models for physiological, genetic, and developmental research.
• * The physiological impacts of altered gravity on whole organisms remain incompletely understood.
• * Bone formation and gene expression are key areas affected by environmental changes.

Purpose of the Study:

• * To investigate the effects of altered gravity and drug treatments on bone formation in zebrafish.
• * To analyze whole genome gene expression changes in response to these stimuli.
• * To characterize the physiological consequences of hypergravity and specific drug interventions.

Main Methods:

• * Utilized morphometric tools and an objective scoring system for skeletal development.
• * Conducted microarray transcriptome analysis to assess gene expression.
• * Employed drug treatments (parathyroid hormone and vitamin D3) and hypergravity (3g) exposure.

Main Results:

• * Parathyroid hormone (PTH) and vitamin D3 (VitD3) treatments altered bone formation, with VitD3 affecting general physiology and PTH impacting development.
• * Hypergravity exposure (3g) led to increased head size and bone formation in cranial bones.
• * Gene expression analysis revealed significant changes in skeletal, muscular, nervous, endocrine, and cardiovascular systems under hypergravity.

Conclusions:

• * Altered gravity and drug treatments significantly impact zebrafish skeletal development and gene expression.
• * Hypergravity exposure during early development promotes bone formation and alters gene networks.
• * A novel
• Reduced Gravity Paradigm
• was proposed and tested, showing sustained effects on bone formation and gene expression.