Lipid profiling reveals the presence of unique lipid mediators in human milk from healthy and mastitic subjects

• Published in: Biochemical and biophysical research communications Vol. 630; pp. 84 - 91
• Main Authors: Nagasaki, Yuki, Kawai, Erika, Maruoka, Saya, Osumi, Miho, Tsukayama, Izumi, Kawakami, Yuki, Takahashi, Yoshitaka, Okazaki, Yuka, Miki, Yoshimi, Taketomi, Yoshitaka, Yamamoto, Kei, Murakami, Makoto, Suzuki-Yamamoto, Toshiko
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 19.11.2022
• Subjects: anti-inflammatory activity; biomarkers; breast feeding; breast milk; eicosapentaenoic acid; energy; Human milk; humans; lactation; lipid composition; Lipidomics; Mastitis; metabolites; milk; milk composition; Pro-inflammatory lipid mediators; Pro-resolving lipid mediators; Pro-inflammatory lipid mediators; AA; FFA; Mastitis; DOHaD; 18-HEPE; Rv; TX; PUFA; LT; Lipidomics; ESI-MS; LX; SFA; SPM; TG; EPA; LC; PG; Human milk; Pro-resolving lipid mediators; DHA; PD1
• ISSN: 0006-291X; 1090-2104; 1090-2104
• DOI: 10.1016/j.bbrc.2022.09.051

Milk lipids are an important energy source for infants, but the composition of milk lipids has not yet been clarified in detail. In this study, we analyzed free fatty acids and their metabolites in milk from humans and cows. In comparison to cow milk, human milk showed a higher content of free fatty acids including polyunsaturated fatty acids, especially ω-3 fatty acids and their metabolites. Polyunsaturated fatty acids were enriched at an early period of lactation, while saturated fatty acids did not change significantly over the period. Moreover, human milk contained high levels of ω-3 fatty acid metabolites, particularly 18-hydroxyeicosapentaenoic acid, an eicosapentaenoic acid-derived metabolite with anti-inflammatory activity. In comparison with human normal milk, thromboxane B2 and protectin D1 levels were significantly elevated in milk from individuals with mastitis, suggesting that these lipid mediators could be potential biomarkers of obstructive mastitis. Overall, the unique lipid profile of human milk supports the efficacy of breast-feeding for supply of more nutritional and bioactive lipids in comparison to artificial or cow milk to infants, in whom digestive and absorptive functions are still immature. •Human milk is rich in free fatty acids including PUFAs and contains a high ratio of ω-3 PUFAs/ω-6 PUFAs.•PUFAs are enriched in human milk at an early period of lactation.•Human milk abundantly contains specialized pro-resolving mediators, especially 18-HEPE.•TXB2 and PD1 levels are uniquely elevated in human mastitic milk.