This study aims to elucidate the mechanism of lipid metabolism disorder in intrauterine growth retardation (IUGR) pigs and the potential alleviating effects of dimethylglycine sodium salt (DMG-Na). A total of 60 male newborn piglets were selected for this study. Within each litter, one normal birth weight (NBW) male piglet (1.53 ± 0.04 kg) and two IUGR male piglets (0.76 ± 0.06 kg) were chosen based on their birth weight. The piglets were divided into three groups for the study: NBW pigs received a PBS gavage and a common basal diet (NBW-C group), IUGR pigs received the same PBS gavage and common basal diet (IUGR-C group), and IUGR pigs received a 70-mg DMG-Na gavage along with a common basal diet supplemented with 0.1% DMG-Na (IUGR-D group). At 150 d of age, all piglets underwent euthanasia by exsanguination following electrical stunning, after which plasma, liver, and longissimus dorsi (LM) samples were promptly collected. The IUGR-D group demonstrated improvements in plasma parameters (P < 0.05), with lower triglyceride and free fatty acid (FFA) values, and hormone levels (P < 0.05), with lower growth hormone, insulin, and homeostasis model assessment of insulin resistance values. Restoration of lipid metabolism was observed (P < 0.05), with lower triglyceride and FFA, and higher hepatic lipase and total lipase values in the liver, and lower triglyceride and FFA values in the LM. Mitochondrial ETC complexes showed increased levels (P < 0.05), including higher complex III values in the liver, and higher complex I, complex III, and complex V values in the LM. Enhanced levels of energy metabolites were noted (P < 0.05), with higher NAD+, NAD+/NADH, adenosine triphosphate, and mtDNA values, and lower NADH values in the liver and LM. Additionally, meat quality parameters showed improvement (P < 0.05), with higher pH 24 h and a∗ values, and lower drip loss 48 h, L∗, and b∗ values. The expressions of lipid metabolism and mitochondrial function-related genes and proteins were upregulated (P < 0.05) compared to the IUGR-C group. In conclusion, it was indicated that IUGR pigs experienced lipid metabolism disorders and diminished performance. However, supplementation with DMG-Na showed promise in mitigating these adverse physiological effects by safeguarding body tissues and modulating energy metabolism.

中文翻译：

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补充二甲基甘氨酸钠盐改善宫内生长迟缓猪脂质代谢紊乱


本研究旨在阐明宫内生长迟缓 （IUGR） 猪脂质代谢紊乱的机制以及二甲基甘氨酸钠盐 （DMG-Na） 的潜在缓解作用。本研究共选择了 60 头雄性新生仔猪。在每窝中，根据出生体重选择一头正常出生体重 （NBW） 雄性仔猪 （1.53 ± 0.04 kg） 和两头 IUGR 雄性仔猪 （0.76 ± 0.06 kg）。将仔猪分为三组进行研究：NBW 猪接受 PBS 灌胃和普通基础日粮（NBW-C 组），IUGR 猪接受相同的 PBS 灌胃和普通基础日粮（IUGR-C 组），IUGR 猪接受 70 mg DMG-Na 灌胃以及补充 0.1% DMG-Na 的普通基础日粮（IUGR-D 组）。在 150 d 龄时，所有仔猪在电击晕后通过放血进行安乐死，之后及时收集血浆、肝脏和背最长杆 （LM） 样本。IUGR-D 组血浆参数 （P < 0.05） 有所改善，甘油三酯和游离脂肪酸 （FFA） 值较低，激素水平 （P < 0.05） 较低，生长激素、胰岛素和胰岛素抵抗值的稳态模型评估较低。观察到脂质代谢恢复 （P < 0.05），肝脏甘油三酯和 FFA 较低，肝脏脂肪酶和总脂肪酶值较高，LM 甘油三酯和 FFA 值较低。线粒体 ETC 复合物水平升高 （P < 0.05），包括肝脏中较高的复合物 III 值，以及 LM 中较高的复合物 I 、 复合物 III 和复合物 V 值。观察到能量代谢物水平增强 （P < 0.05），肝脏和 LM 中的 NAD+ 、 NAD+/NADH 、 三磷酸腺苷和 mtDNA 值较高，而 NADH 值较低。 此外，肉品质参数显示改善 （P < 0.05），pH 24 h 和 a∗ 值较高，48 h、L∗ 和 b∗ 值滴水损失较低。与 IUGR-C 组相比，脂质代谢和线粒体功能相关基因和蛋白的表达上调 （P < 0.05）。总之，表明 IUGR 猪出现脂质代谢紊乱和生产性能下降。然而，补充 DMG-Na 有望通过保护身体组织和调节能量代谢来减轻这些不良的生理影响。