Dervas Eva, Hetzel Udo, Kipar Anja
Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 268, Zürich, CH-8057, Switzerland.
Immun Ageing. 2025 Jun 19;22(1):22. doi: 10.1186/s12979-025-00519-7.
Aging is a complex and multifaceted biological process that results in the gradual decline of physiological functions over time. It is associated with reduced performance across multiple systems, affecting metabolic, reproductive, musculoskeletal, and immune functions. While immune aging has been extensively studied in endothermic animals, and in particular mammals such as laboratory rodents, comparatively little is known about how aging manifests in ectothermic vertebrates like reptiles. This study explored the lymphoid tissue (spleen and thymus) of Boa constrictor, a boid snake indigenous to South and Central America and Mexico, but widely kept in captivity all over the world, for potential age-related changes. We observed a significant decrease in cellularity in the spleen, coupled with an increase in organ size correlated with age. In both spleen and thymus the connective tissue of capsule and trabeculae increased significantly with age, indicative of progressive fibrosis. In addition, several changes were observed with increasing frequency in older animals, epithelial hyperplasia in the thymic medulla as well stromal fibrosis and an increasing infiltration by so-called granular cells in both organs. Granular cells likely represent a leukocyte subtype; their presence indicates a progressive chronic low-grade inflammatory state in the lymphoid organs, a feature known as inflammaging in other animal classes. They may also play a role in the progressive fibrosis of the connective tissue. The results firstly describe morphological evidence of aging in B. constrictor and indicate similarities in the aging across animal classes.
衰老 是一个复杂且多方面的生物学过程，随着时间的推移会导致生理功能逐渐衰退。它与多个系统的功能下降有关，影响代谢、生殖、肌肉骨骼和免疫功能。虽然免疫衰老在恒温动物，特别是在实验室啮齿动物等哺乳动物中已得到广泛研究，但对于像爬行动物这样的变温脊椎动物衰老如何表现却知之甚少。本研究探索了红尾蚺的淋巴组织（脾脏和胸腺），红尾蚺是一种原产于南美洲、中美洲和墨西哥的蚺科蛇类，但在世界各地广泛人工饲养，研究其潜在的与年龄相关的变化。我们观察到脾脏细胞数量显著减少，同时器官大小随年龄增加。在脾脏和胸腺中，被膜和小梁的结缔组织均随年龄显著增加，表明有进行性纤维化。此外，在老年动物中观察到几种变化的频率增加，胸腺髓质上皮增生以及基质纤维化，且两个器官中所谓的颗粒细胞浸润增加。颗粒细胞可能代表一种白细胞亚型；它们的存在表明淋巴器官中存在进行性慢性低度炎症状态，这一特征在其他动物类群中被称为炎症衰老。它们也可能在结缔组织的进行性纤维化中起作用。这些结果首次描述了红尾蚺衰老的形态学证据，并表明不同动物类群衰老过程存在相似性。
