Docosahexaenoic acid (DHA, C22:6, ω-3), an ω-3 polyunsaturated fatty acid (PUFA), is critical for brain growth, development, and cognitive ability. It is consumed by offspring via milk during lactation. However, the toxic heavy metal lead (Pb) readily passes into the mammary glands of mother animals and then to offspring through milk. Here, we investigated whether DHA composition of milk and mammary gland tissues is affected by Pb exposure. Mother rats were exposed to Pb via drinking water (0.1%). The fatty acid profile and levels of reduced glutathione (GSH), lipid peroxide (LPO), and pro-inflammatory TNF-α in milk and mammary tissues were measured. Levels of DHA and antioxidant GSH decreased (P < 0.05), while LPO and TNF-α levels increased (P < 0.05) both in milk and mammary tissues. Our results suggest that toxic Pb exposure can upset the level of milk DHA, which may affect brain growth and development, and hence cognitive ability in adulthood and later life.

中文翻译：

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二十二碳六烯酸（DHA，C22：6，ω-3）铅（Pb）暴露会严重影响哺乳母鼠的牛奶和乳腺组织。

二十二碳六烯酸（DHA，C22：6，ω-3），一种ω-3多不饱和脂肪酸（PUFA），对大脑的生长，发育和认知能力至关重要。哺乳期间后代会通过牛奶食用它。但是，有毒的重金属铅（Pb）容易进入母乳腺，然后通过牛奶进入后代。在这里，我们调查了牛奶和乳腺组织中的DHA组成是否受到Pb暴露的影响。母鼠通过饮用水（0.1％）暴露于铅。测量了牛奶和乳腺组织中的脂肪酸谱和还原型谷胱甘肽（GSH），脂质过氧化物（LPO）和促炎性TNF-α的水平。牛奶和乳腺组织中的DHA和抗氧化剂GSH的含量均降低（P <0.05），而LPO和TNF-α的含量均升高（P <0.05）。