International Journal of Molecular Zoology 2024, Vol.14, No.4, 197-210 http://animalscipublisher.com/index.php/ijmz 204 5.3 Lessons from the naked mole rat for understanding vertebrate longevity The study of the naked mole rat provides valuable insights into the mechanisms underlying vertebrate longevity. The naked mole rat's unique immune system, combined with its resistance to cancer and other age-related diseases, challenges traditional theories of aging and suggests that immune function plays a critical role in longevity. By understanding the molecular and genetic adaptations that contribute to the naked mole rat's long lifespan, researchers can identify potential targets for interventions aimed at extending human healthspan and lifespan (Heinze et al., 2017). For instance, the naked mole rat's low circulating levels of specific amino acids and its unique metabolomic profile resemble those observed in other long-lived species, indicating that metabolic pathways may be key determinants of longevity (Lewis et al., 2018). Additionally, the naked mole rat's ability to maintain physiological functions and resist age-related decline provides a model for studying successful aging and developing strategies to mitigate the effects of aging in humans (Edrey et al., 2011). 6 Interplay Between Immune Function, Longevity, and Disease Resistance 6.1 Immune function as a balancing act between longevity and disease resistance The immune system plays a crucial role in maintaining health and longevity in vertebrates. However, the relationship between immune function and longevity is complex and often involves trade-offs. For instance, the splicing factor RNP-6/PUF60 has been shown to suppress immunity while promoting longevity in C. elegans, indicating a trade-off between these processes (Kew et al., 2020). Similarly, the transcription factor TCER-1 in C. elegans enhances longevity but represses immunity, suggesting that mechanisms promoting lifespan may concurrently suppress immune responses to balance energy expenditure and physiological demands (Ghazi et al., 2019). These findings highlight the intricate balancing act between maintaining robust immune defenses and promoting longevity. 6.2 Trade-offs between immune response and other physiological processes Trade-offs between immune function and other physiological processes are well-documented across various vertebrate species. For example, in desert tortoises (Gopherus agassizii), a trade-off exists between natural antibodies (innate immunity) and acquired antibodies (adaptive immunity), with long-term elevations in acquired antibodies potentially compromising other physiological functions (Sandmeier et al., 2012). In loggerhead musk turtles (Sternotherus minor), sex-based differences in immune responses suggest that males with higher body condition indices exhibit more stressed phenotypes, indicating a trade-off between maintaining body condition and immune function. Additionally, in Drosophila Cytoraces, long-lived individuals exhibit reduced immune responses when challenged with pathogens, further supporting the existence of trade-offs between lifespan and immunity (Sinam et al., 2016). 6.3 Examples from vertebrate species: the cost of immunity The cost of immunity is evident in various vertebrate species, where maintaining a robust immune system can come at the expense of other life history traits. For instance, in the study of loggerhead musk turtles, males with higher body condition indices showed more stressed phenotypes, suggesting that the energy allocated to maintaining body condition may detract from immune function (López-Pérez et al., 2020). In desert tortoises, the long-term elevation of acquired antibodies indicates a significant investment in adaptive immunity, which may impact other physiological processes. Furthermore, the study on C. elegans revealed that the splicing factor RNP-6/PUF60 and the transcription factor TCER-1 both promote longevity at the cost of immune suppression, illustrating the evolutionary trade-offs between immunity and lifespan. These examples underscore the complex interplay between immune function, longevity, and disease resistance in vertebrates, where the cost of immunity must be balanced against other physiological demands to optimize survival and reproductive success. 7 Implications for Conservation and Wildlife Management 7.1 The role of immune function in species survival Immune function plays a critical role in the survival and longevity of vertebrate species. Studies have shown that body condition and immune responsiveness are significant predictors of long-term survival and reproductive success in wild populations. For instance, in a study on house wrens, neonates with higher immune responsiveness and intermediate hematocrit levels were found to have higher recruitment and longevity, indicating that robust
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