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Updated: Aug 10, 2026
Preparation of Acute Hippocampal Slices from Rats and Transgenic Mice for the Study of Synaptic Alterations during Aging and Amyloid Pathology
Published on: March 23, 2011
Non-transgenic guinea pig strains exhibit divergent age-related changes in hippocampal mitochondrial respiration
Maureen A Walsh1, Amanda S Latham2, Qian Zhang1
1Department of Health and Exercise Science, Colorado State University, Fort Collins, Colorado, USA.
Aim:
Alzheimer's disease (AD) is the most common form of dementia. However, while 150+ animal models of AD exist, drug translation from preclinical models to humans for treatment usually fails. One factor contributing to low translation is likely the absence of neurodegenerative models that also encompass the multi-morbidities of human aging. We previously demonstrated that, in comparison to the PigmEnTed (PET) guinea pig strain which models "typical" brain aging, the Hartley strain develops hallmarks of AD like aging humans. Hartleys also exhibit age-related impairments in cartilage and skeletal muscle. Impaired mitochondrial respiration is one driver of both cellular aging and AD. In humans with cognitive decline, diminished skeletal muscle and brain respiratory control occurs in parallel. We previously reported age-related declines in skeletal muscle mitochondrial respiration in Hartleys. It is unknown if there is concomitant mitochondrial dysfunction in the brain.
Methods:
Therefore, we assessed hippocampal mitochondrial respiration in 5- and 12-month Hartley and PET guinea pigs using high-resolution respirometry.
Results:
At 12 months, PETs had higher complex I supported mitochondrial respiration paralleling their increase in body mass compared to 5 months PETs. Hartleys were also heavier at 12 months compared to 5 months but did not have higher complex I respiration. Compared to 5 months Hartleys, 12 months Hartleys had lower complex I mitochondrial efficiency and compensatory increases in mitochondrial proteins collectively suggesting mitochondrial dysfunction with age.
Conclusions:
Therefore, Hartleys might be a relevant model to test promising therapies targeting mitochondria to slow brain aging and AD progression.
Insights
Hartley guinea pigs show age-related mitochondrial dysfunction in the brain, suggesting they are a valuable model for Alzheimer's disease (AD) research and testing new therapies.
Area of Science:
- Neuroscience
- Aging Research
- Mitochondrial Biology
Background:
- Alzheimer's disease (AD) drug translation fails due to lack of models reflecting human aging comorbidities.
- Hartley guinea pigs, unlike PET guinea pigs, develop AD hallmarks and age-related issues in cartilage and muscle.
- Impaired mitochondrial respiration drives cellular aging and AD; human cognitive decline parallels skeletal muscle and brain respiratory deficits.
Purpose of the Study:
- To investigate if Hartley guinea pigs exhibit age-related mitochondrial dysfunction in the brain.
- To compare hippocampal mitochondrial respiration in aging Hartley and PET guinea pigs.
Main Methods:
- High-resolution respirometry was used to assess hippocampal mitochondrial respiration.
- Hartley and PET guinea pigs at 5 and 12 months of age were studied.
Main Results:
- PET guinea pigs showed increased complex I respiration with age and weight gain.
- Hartley guinea pigs did not show increased complex I respiration despite weight gain.
- Aging Hartley guinea pigs displayed reduced complex I mitochondrial efficiency and compensatory protein increases, indicating dysfunction.
Conclusions:
- Hartley guinea pigs exhibit age-related mitochondrial dysfunction in the brain.
- This strain may serve as a relevant model for testing mitochondria-targeted therapies for brain aging and AD.
