Aydin Suleyman, Ozkan Yusuf, Erman Fazilet, Gurates Bilgin, Kilic Nermin, Colak Ramis, Gundogan Tugba, Catak Zekiye, Bozkurt Mahmut, Akin Okhan, Sen Yasar, Sahn Ibrahim
Department of Biochemistry and Clinical Biochemistry, School of Medicine, Firat University, Firat Medical Center, Elazig, Turkey.
Nutrition. 2008 Jul-Aug;24(7-8):689-93. doi: 10.1016/j.nut.2008.03.020. Epub 2008 May 21.
The peptide hormones ghrelin and leptin have been found in blood and breast milk. This study was undertaken to investigate whether breast milk also contains obestatin, which is derived from the same gene as ghrelin but has opposite actions, and to characterize the relations among serum and milk ghrelin, obestatin, and leptin levels in lactating mothers.
Venous blood, colostrum, and mature milk were obtained from healthy lactating women (n = 31) just before suckling. The ghrelin and obestatin concentrations were determined by radioimmunoassay. Leptin levels were measured by enzyme-amplified sensitivity immunoassay.
Obestatin levels in colostrum (538.9 pg/mL) and mature milk (528.5 pg/mL) were more than twice the corresponding blood levels (270.3 and 289.4 pg/mL, respectively). In contrast, leptin levels in colostrum (2.01 ng/mL) and mature milk (2.04 ng/mL) were more than five-fold lower than the corresponding blood levels (11.54 ng/mL). There was no correlation between breast milk ghrelin levels and leptin (r = -0.18, P > 0.05). However, there was a positive correlation between leptin levels in breast milk and blood (r = 0.369, P < 0.05).
The origin of milk obestatin is not currently known, but it comes from the blood or breast and may drain through the mammary glands into the milk. Ghrelin, obestatin, and leptin in the milk may directly affect appetite and their levels may be related to the regulation of energy balance and the pathogenesis of obesity.
已在血液和母乳中发现肽类激素胃饥饿素和瘦素。本研究旨在调查母乳中是否也含有与胃饥饿素源自同一基因但作用相反的肥胖抑制素，并确定哺乳期母亲血清和乳汁中胃饥饿素、肥胖抑制素及瘦素水平之间的关系。
在哺乳前从31名健康哺乳期妇女获取静脉血、初乳和成熟乳。采用放射免疫分析法测定胃饥饿素和肥胖抑制素浓度。通过酶放大免疫分析法测量瘦素水平。
初乳（538.9 pg/mL）和成熟乳（528.5 pg/mL）中的肥胖抑制素水平是相应血液水平（分别为270.3和289.4 pg/mL）的两倍多。相比之下，初乳（2.01 ng/mL）和成熟乳（2.04 ng/mL）中的瘦素水平比相应血液水平（11.54 ng/mL）低五倍多。母乳中胃饥饿素水平与瘦素之间无相关性（r = -0.18，P > 0.05）。然而，母乳和血液中的瘦素水平呈正相关（r = 0.369，P < 0.05）。
目前尚不清楚乳汁中肥胖抑制素的来源，但它来自血液或乳腺，可能通过乳腺排入乳汁。乳汁中的胃饥饿素、肥胖抑制素和瘦素可能直接影响食欲，其水平可能与能量平衡调节及肥胖发病机制有关。
