IPMA-Portuguese Institute for the Sea and Atmosphere, I.P., Av. Doutor Alfredo Magalhães Ramalho, nº 6, 1495-165 Algés, Portugal.
CIIMAR-Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos S/N, 4450-208 Matosinhos, Portugal.
Toxins (Basel). 2019 Jul 13;11(7):408. doi: 10.3390/toxins11070408.
Warmer seawater temperatures are expected to increase harmful algal blooms (HABs) occurrence, intensity, and distribution. Yet, the potential interactions between abiotic stressors and HABs are still poorly understood from ecological and seafood safety perspectives. The present study aimed to investigate, for the first time, the bioaccumulation/depuration mechanisms and ecotoxicological responses of juvenile gilthead seabream () exposed to paralytic shellfish toxins (PST) under different temperatures (18, 21, 24 °C). PST were detected in fish at the peak of the exposure period (day five, 0.22 µg g N-sulfocarbamoylGonyautoxin-1-2 (C1 and C2), 0.08 µg g Decarbamoylsaxitoxin (dcSTX) and 0.18 µg g Gonyautoxin-5 (B1)), being rapidly eliminated (within the first 24 h of depuration), regardless of exposure temperature. Increased temperatures led to significantly higher PST contamination (275 µg STX eq. kg). During the trial, fish antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glutathione S-transferase, GST) in both muscle and viscera were affected by temperature, whereas a significant induction of heat shock proteins (HSP70), Ubiquitin (Ub) activity (viscera), and lipid peroxidation (LPO; muscle) was observed under the combination of warming and PST exposure. The differential bioaccumulation and biomarker responses observed highlight the need to further understand the interactive effects between PST and abiotic stressors, to better estimate climate change impacts on HABs events, and to develop mitigation strategies to overcome the potential risks associated with seafood consumption.
预计海水变暖将增加有害藻类大量繁殖（HABs）的发生频率、强度和分布。然而，从生态学和海鲜安全的角度来看，人们对非生物胁迫因子与 HABs 之间的潜在相互作用仍然知之甚少。本研究首次旨在调查，在不同温度（18、21、24°C）下，幼期金头鲷（）暴露于麻痹性贝类毒素（PST）时的生物积累/净化机制和生态毒理学反应。在暴露期（第五天）的高峰期，鱼体内检测到 PST（C1 和 C2 的 0.22 µg g N-磺酰基carbamoylGonyautoxin-1-2、0.08 µg g 脱碳酰基石房蛤毒素（dcSTX）和 0.18 µg g Gonyautoxin-5（B1）），无论暴露温度如何，PST 都能迅速消除（在净化的前 24 小时内）。升高温度会导致 PST 污染显著增加（275 µg STX eq. kg）。在试验过程中，肌肉和内脏中的鱼抗氧化酶活性（超氧化物歧化酶，SOD；过氧化氢酶，CAT；谷胱甘肽 S-转移酶，GST）受到温度的影响，而 HSP70、泛素（Ub）活性（内脏）和脂质过氧化（LPO；肌肉）在升温与 PST 暴露的组合下显著诱导。观察到的差异生物积累和生物标志物反应强调需要进一步了解 PST 与非生物胁迫因子之间的相互作用效应，以更好地估计气候变化对 HABs 事件的影响，并制定缓解策略以克服与海鲜消费相关的潜在风险。
