Facultad de Ciencias Agronómicas, Universidad de el Salvador. Autopista Norte y Final 25ª, Avenida Norte, Ciudad Universitaria, C.P. 01101 San Salvador, El Salvador.
Facultad de Ciencias, Universidad Autónoma de San Luis Potosí, Avenida Chapultepec #1570, C.P. 78295 San Luis Potosí, San Luis Potosí, Mexico; Centro de Investigaciones en Ciencias de la Salud y Biomedicina, Universidad Autónoma de San Luis Potosí, Av. Sierra Leona #550, Lomas de San Luis, C.P. 78210 San Luis Potosí, San Luis Potosí, Mexico.
Mutat Res Genet Toxicol Environ Mutagen. 2023 Apr;887:503596. doi: 10.1016/j.mrgentox.2023.503596. Epub 2023 Jan 28.
Contamination in marine ecosystems is of the most critical threats to marine turtles. The identification of useful biomarkers to detect and monitor the physiological and clinical effects of pollutants on these populations will allow early detection of alterations (e.g., mutagenic damages) that could risk their viability or favor the development of diseases, thus threatening the biodiversity of these ecosystems and human population. This study is aimed at describing and quantifying nuclear anomalies in peripheral blood erythrocytes of green turtles (Chelonia mydas) from three distinct foraging areas in Mexico (Akumal, Xcalak, and Punta Herrero). We developed a novel morphological index that could be used as a biomarker to identify abnormal nuclei in peripheral blood erythrocytes. Here we describe for the first time in C. mydas, with a species-specific staining protocol, distinct nuclear abnormalities such as blebbed, lobed, notched, eight shape nuclei, and binucleated cells. These nuclear abnormalities were present in > 90 % of the subjects (n = 30). Moreover, 50 % of the organisms presented erythrocytes with micronuclei. The number of nuclear abnormalities did not correlate with size of the green turtles or differ between sites, or health status. We found a higher frequency of green turtles with nuclear abnormalities in the southern region (Punta Herrero and Xcalak) with the highest frequency of micronucleus and buds. The former could be associated to the constant exposure to chemical pollutants of oceanographic origin in the southern coast of Quintana Roo. Furthermore, the increasing anthropogenic pollution in Akumal could also explain the highest variability in the number of nuclear abnormalities presented in resident individuals. We propose that a long-term monitoring programs of green turtle populations in the Mexican Caribbean that include a micronucleus test could be a useful to determine possible mutagenic damage in these animals.
海洋生态系统的污染是对海龟最具威胁的因素之一。识别有用的生物标志物，以检测和监测污染物对这些种群的生理和临床影响，将允许早期发现可能危及它们生存能力或促进疾病发展的变化（例如，诱变损伤），从而威胁到这些生态系统的生物多样性和人类种群。本研究旨在描述和量化来自墨西哥三个不同觅食区（阿克曼、斯卡拉克和蓬塔赫雷罗）的绿海龟（Chelonia mydas）外周血红细胞中的核异常。我们开发了一种新的形态学指数，可以用作生物标志物来识别外周血红细胞中的异常核。在这里，我们首次在 C. mydas 中描述了具有物种特异性染色方案的独特核异常，例如泡状、叶状、有缺口、八角形核和双核细胞。这些核异常存在于> 90%的研究对象（n = 30）中。此外，50%的生物体表现出有微核的红细胞。核异常的数量与绿海龟的大小无关，也不随地点或健康状况而不同。我们发现，在南部地区（蓬塔赫雷罗和斯卡拉克），具有核异常的绿海龟频率更高，微核和芽的频率更高。这可能与昆塔纳罗奥南部海岸不断暴露于海洋起源的化学污染物有关。此外，阿克曼不断增加的人为污染也可以解释居住个体中核异常数量的最大变异性。我们建议，在墨西哥加勒比地区对绿海龟种群进行长期监测计划，包括微核试验，这可能是确定这些动物可能发生诱变损伤的有用方法。
