Department of Zoology, Faculty of Science, Al Azhar University (Assiut Branch), 71524 Assiut, Egypt.
Department of Zoology, Faculty of Science, Sohag University, 8562 Sohag, Egypt.
Tissue Cell. 2021 Aug;71:101512. doi: 10.1016/j.tice.2021.101512. Epub 2021 Feb 23.
Although microplastics (MPs) have received increasing focus and currently have become an emerging area of research, there is limited knowledge about their effect on whole body histology of fish. In this study, tilapia (Oreochromis niloticus) early juveniles were exposed to 1, 10, or 100 mg/L of MPs for 15 days and 15 days post-exposure, after which whole body histological examinations were performed. Histological analysis of kidney revealed congestion of blood capillaries, inflammatory cells, loss of basophilic cytoplasm in several tubules, vacuolated tubules, shrinking of convoluted tubules, widening of intertubular space, complete deformation, glomerular atrophy, vacuolated glomerular cells, and signs of fatty tubules. The liver tissue exhibited vacuoles, hydropic degeneration, necrotic area, severe deformation of hepatocytes, pyknotic nuclei, and dilation and congestion of blood sinusoids. The pancreatic tissue revealed shrunken and degenerated acini with pyknotic nuclei, hemorrhage, necrotic area, inflammatory cells, fatty cells, and congested blood capillaries. In the muscle tissue, fiber core dissociation, edema, necrosis, segmented fibers, and inflammatory cells were detected. The gill tissue demonstrated dilation and congestion of blood vessels, complete lamellar fusions, lifting of epithelium, shortening and degeneration of secondary lamellae, hyperplasia, and deposition of MPs between primary lamellae. In the spinal cord and notochord, the effects were degeneration and protrusion of meninges, deformation and deviation of notochord from its central axis, edema, degeneration of notochord (disappearance of vacuolar cells), deviation of spinal cord from the central axis, and loss of vacuolar cells in notochord. The intestinal tissue exhibited degeneration of basement membrane, inflammatory cells, goblet cells, atrophy of submucosa, pyknotic nuclei, hemorrhage, and vacuolization of mucosal cells. The histopathological changes in different organs were noticed even post-exposure in fish exposed to MPs compared to those in control fish and these changes were concentration dependent. In conclusion, these data together with our previous data suggest that MPs can cause different changes, ranging from biochemical alterations in single cells to lesions in the entire tissue, which can affect the vitality and life of fish.
虽然微塑料（MPs）已经受到越来越多的关注，并且目前已经成为一个新兴的研究领域，但关于它们对鱼类整体组织学的影响知之甚少。在这项研究中，罗非鱼（Oreochromis niloticus）早期幼鱼暴露于 1、10 或 100mg/L MPs 中 15 天，暴露后 15 天进行全身组织学检查。肾脏组织学分析显示毛细血管充血、炎症细胞浸润、部分肾小管嗜碱性细胞质丢失、空泡化肾小管、卷曲小管萎缩、肾小管间空间增宽、肾小球完全变形、肾小球细胞空泡化、脂肪小管迹象。肝组织显示空泡、水肿变性、坏死区、肝细胞严重变形、固缩核、血窦扩张和充血。胰腺组织显示萎缩和退化的腺泡、固缩核、出血、坏死区、炎症细胞、脂肪细胞和充血的毛细血管。在肌肉组织中，检测到纤维核心解离、水肿、坏死、分段纤维和炎症细胞。鳃组织显示血管扩张和充血、完整的板层融合、上皮抬起、次级板层缩短和退化、增生以及 MPs 在初级板层之间的沉积。在脊髓和脊索中，脑膜变性和突出、脊索偏离中心轴、水肿、脊索变性（空泡细胞消失）、脊髓偏离中心轴以及脊索中空泡细胞丢失。肠组织显示基膜变性、炎症细胞、杯状细胞、黏膜下萎缩、固缩核、出血和黏膜细胞空泡化。与对照组相比，暴露于 MPs 的鱼类在暴露后不同器官都出现了组织病理学变化，这些变化与浓度有关。总之，这些数据与我们之前的数据一起表明， MPs 可以引起不同的变化，从单个细胞的生化改变到整个组织的病变，这可能会影响鱼类的活力和生命。
