Aging Promotes Spontaneous Liver Injury: Insights from Metabolic, Inflammatory, and Fibrotic Pathways in C57BL/6 Mice

Area of Science:

• Hepatology
• Aging Research
• Metabolic Disorders

Background:

• Aging is a primary risk factor for liver injury.
• Understanding age-related changes in liver function is crucial for public health.
• Sex-specific differences in aging liver may exist.

Purpose of the Study:

• To investigate spontaneous liver injury development with aging.
• To examine sex-related differences in age-associated liver injury mechanisms.
• To analyze alterations in fatty acid metabolism, immune response, and cellular stress in aging mice.

Main Methods:

• Comparison of aged (20-22 months) and young (8-10 weeks) male and female C57BL/6 mice.
• Assessment of body weight, metabolic profiles, and fatty acid metabolism.
• Measurement of oxidative stress, cellular senescence, inflammatory markers, and cytokines/chemokines.
• Evaluation of hepatic fibrosis indices, including smooth muscle actin-α, collagen, and transforming growth factor-β.

Main Results:

• Aged mice showed increased body weight, altered metabolic profiles, and impaired fatty acid metabolism compared to young mice.
• Increased oxidative stress, cellular senescence, inflammation, and cytokine/chemokine levels were observed in aged mice.
• Aged mice exhibited heightened indices of hepatic fibrosis, indicated by upregulated fibrotic markers.

Conclusions:

• Aging promotes spontaneous liver injury by exacerbating oxidative stress, steatosis, inflammation, and fibrosis.
• Chronological age impacts liver susceptibility to secondary stressors like diet or infection.
• Understanding sex-specific metabolic and inflammatory changes with aging is vital for chronic liver disease research and targeted therapies.