Comprehensive healthspan assessments and influence of sex as a biological variable in aging rats

Chandra, A.; Aversa, Z.; Zhang, X.; Farr, J. N.; David, A.; Sharma, R.; Tchkonia, T.; Kirkland, J. L.; Robbins, P. D.; Niedernhofer, L. J.; Jurk, D.; Passos, J.; Monroe, D.; Miller, J. D.; LeBrasseur, N. K.; Ikeno, Y.; Khosla, M.D, S.; Pignolo, R. J.

doi:10.1101/2025.09.22.677661

bioRxiv · 10.1101/2025.09.22.677661

Comprehensive healthspan assessments and influence of sex as a biological variable in aging rats

Chandra, A.·Aversa, Z.·Zhang, X.·Farr, J. N.·David, A.·Sharma, R.·Tchkonia, T.·Kirkland, J. L.·Robbins, P. D.·Niedernhofer, L. J.·Jurk, D.·Passos, J.·Monroe, D.·Miller, J. D.·LeBrasseur, N. K.·Ikeno, Y.·Khosla, M.D, S.·Pignolo, R. J.

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Abstract

Rats share a significant amount of genetic and physiological similarity with humans. Many biological processes and pathways are conserved between rats and humans, making rats a suitable model for studying various aspects of human health and disease. Using rats as an aging model offers a more ethical alternative to using larger, longer-lived animals like primates. Rats are easier to handle in laboratory settings, as compared to non-human primates, both of which have physiological functions like humans. To date, there are very few studies which have comprehensively studied age-related changes in rat physiology. Here we present a longitudinal assessment of several aspects of Brown-Norway rat physiology and histopathology using molecular and functional assessments at 6-, 17- and 27 months of age. Our studies thus provide age-related healthspan parameters, which can be used as reference for genetic or pharmacological rat models of aging.

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Chandra, A., Aversa, Z., Zhang, X., Farr, J. N., David, A., Sharma, R., Tchkonia, T., Kirkland, J. L., Robbins, P. D., Niedernhofer, L. J., Jurk, D., Passos, J., Monroe, D., Miller, J. D., LeBrasseur, N. K., Ikeno, Y., Khosla, M.D, S., Pignolo, R. J.. 2025-09-22. Comprehensive healthspan assessments and influence of sex as a biological variable in aging rats. https://doi.org/10.1101/2025.09.22.677661

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