Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061, USA.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae161.
Study objectives were to determine the effects of mitoquinol (MitoQ, a mitochondrial-targeted antioxidant) on biomarkers of metabolism and inflammation during acute heat stress (HS). Crossbred barrows [n = 32; 59.0 ± 5.6 kg body weight (BW)] were blocked by BW and randomly assigned to 1 of 4 environmental-therapeutic treatments: 1) thermoneutral (TN) control (n = 8; TNCon), 2) TN and MitoQ (n = 8; TNMitoQ), 3) HS control (n = 8; HSCon), or 4) HS and MitoQ (n = 8; HSMitoQ). Pigs were acclimated for 6 d to individual pens before study initiation. The trial consisted of two experimental periods (P). During P1 (2 d), pigs were fed ad libitum and housed in TN conditions (20.6 ± 0.8 °C). During P2 (24 h), HSCon and HSMitoQ pigs were exposed to continuous HS (35.2 ± 0.2 °C), while TNCon and TNMitoQ remained in TN conditions. MitoQ (40 mg/d) was orally administered twice daily (0700 and 1800 hours) during P1 and P2. Pigs exposed to HS had increased rectal temperature, skin temperature, and respiration rate (+1.5 °C, +6.8 °C, and +101 breaths per minute, respectively; P < 0.01) compared to their TN counterparts. Acute HS markedly decreased feed intake (FI; 67%; P < 0.01); however, FI tended to be increased in HSMitoQ relative to HSCon pigs (1.5 kg vs. 0.9 kg, respectively; P = 0.08). Heat-stressed pigs lost BW compared to their TN counterparts (-4.7 kg vs. +1.6 kg, respectively; P < 0.01); however, the reduction in BW was attenuated in HSMitoQ compared to HSCon pigs (-3.9 kg vs. -5.5 kg, respectively; P < 0.01). Total gastrointestinal tract weight (empty tissue and luminal contents) was decreased in HS pigs relative to their TN counterparts (6.2 kg vs. 8.6 kg, respectively; P < 0.01). Blood glucose increased in HSMitoQ relative to HSCon pigs (15%; P = 0.04). Circulating non-esterified fatty acids (NEFA) increased in HS compared to TN pigs (P < 0.01), although this difference was disproportionately influenced by elevated NEFA in HSCon relative to HSMitoQ pigs (251 μEq/L vs. 142 μEq/L; P < 0.01). Heat-stressed pigs had decreased circulating insulin relative to their TN counterparts (47%; P = 0.04); however, the insulin:FI ratio tended to increase in HS relative to TN pigs (P = 0.09). Overall, circulating leukocytes were similar across treatments (P > 0.10). Plasma C-reactive protein remained similar among treatments; however, haptoglobin increased in HS relative to TN pigs (48%; P = 0.03). In conclusion, acute HS exposure negatively altered animal performance, inflammation, and metabolism, which were partially ameliorated by MitoQ.
研究目的是确定米托醌（MitoQ，一种靶向线粒体的抗氧化剂）对急性热应激（HS）期间代谢和炎症生物标志物的影响。杂交公猪[n = 32；59.0 ± 5.6 kg 体重（BW）]按 BW 分组并随机分配到 4 种环境治疗处理之一：1） 常温对照（TNCon），2） 常温+MitoQ（TNMitoQ），3） HS 对照（HSCon），或 4） HS+MitoQ（HSMitoQ）。猪在开始研究前适应了 6 天的个体围栏。试验包括两个实验期（P）。在 P1（2 天）期间，猪自由采食并在 TN 条件下饲养（20.6 ± 0.8°C）。在 P2（24 小时）期间，HSCon 和 HSMitoQ 猪持续暴露于 HS（35.2 ± 0.2°C），而 TNCon 和 TNMitoQ 则保持在 TN 条件下。MitoQ（40mg/d）在 P1 和 P2 期间每天口服两次（0700 和 1800 小时）。与 TN 对应物相比，暴露于 HS 的猪的直肠温度、皮肤温度和呼吸率分别升高了 1.5°C、6.8°C 和 101 次/分钟（P < 0.01）。急性 HS 显著降低了采食量（FI；67%；P < 0.01）；然而，与 HSCon 猪相比，HSMitoQ 猪的 FI 趋于增加（分别为 1.5 kg 和 0.9 kg；P = 0.08）。与 TN 对应物相比，HS 应激猪的 BW 减轻（分别为-4.7 kg 和+1.6 kg；P < 0.01）；然而，与 HSCon 猪相比，HSMitoQ 猪 BW 的减少量减少（分别为-3.9 kg 和-5.5 kg；P < 0.01）。与 TN 对应物相比，总胃肠道重量（空组织和腔内容物）减少（分别为 6.2 kg 和 8.6 kg；P < 0.01）。与 HSCon 猪相比，HSMitoQ 猪的血糖升高（15%；P = 0.04）。与 TN 猪相比，循环非酯化脂肪酸（NEFA）在 HS 中增加（P < 0.01），尽管 HSCon 猪的 NEFA 升高不成比例地影响了 HSMitoQ 猪（251 μEq/L 和 142 μEq/L；P < 0.01）。与 TN 对应物相比，HS 应激猪的循环胰岛素减少（47%；P = 0.04）；然而，与 TN 猪相比，HS 猪的胰岛素：FI 比值趋于增加（P = 0.09）。总的来说，循环白细胞在处理之间相似（P > 0.10）。血浆 C 反应蛋白在处理之间保持相似；然而，与 TN 猪相比，触珠蛋白增加（48%；P = 0.03）。总之，急性 HS 暴露对动物性能、炎症和代谢产生了负面影响，这些负面影响部分被 MitoQ 减轻。
