Milk sphingomyelin accelerates enzymatic and morphological maturation of the intestine in artificially reared rats.
OBJECTIVE
Sphingomyelin (SPM) is the dominant phospholipid, comprising 38% of total human milk phospholipids. Although little is known about the nutritional importance of SPM during the neonatal period, SPM may affect the growth and development of tissues in the newborn infant through mechanisms regulating cell proliferation and differentiation. We evaluated the effect of sphingomyelin (SPM) in artificially reared rats as a suitable model of gut maturation in the suckling infant.


METHODS
Seven-day-old Sprague-Dawley rat pups were cannulated intragastrically and reared artificially on milk containing 0.5% SPM or 0.5% phosphatidylcholine (PC) for 1 week.


RESULTS
Intestinal lactase activity in the SPM group was significantly lower than that in the control or PC group. Upon histologic examination, intestinal villi were found to be occupied with vacuolated cells in the control and the PC group, whereas the vacuolated cells were restricted to the tip of villi in the SPM group. The Auerbach nerve plexus area of the ileum in the SPM group was significantly greater, possibly due to accelerated development, than that in the control group or PC group.


CONCLUSIONS
The present results suggest that SPM, the dominant phospholipid in milk, plays an important role in neonatal gut maturation during the suckling period.
Motouri
Mutsumi
M
Technology and Research Institute, Snow Brand Milk Products Co. Ltd., Minamidai, Kawagoe, Saitama 350-1165, Japan. m-motouri@snowbrand.co.jp
Matsuyama
Hiroaki
H
Yamamura
Jun-ichi
J
Tanaka
Miyako
M
Aoe
Seiichiro
S
Iwanaga
Toshihiko
T
Kawakami
Hiroshi
H
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D007413:Intestinal Mucosa / Q000166:cytology / Q000201:enzymology* / Q000473:pathology*; D007421:Intestine, Small / Q000201:enzymology / Q000254:growth & development* / Q000378:metabolism; D043322:Lactase; D008892:Milk / Q000737:chemistry; D008895:Milk, Human / Q000737:chemistry; D023421:Models, Animal; D009929:Organ Size / Q000187:drug effects; D010713:Phosphatidylcholines / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013109:Sphingomyelins / Q000494:pharmacology / Q000502:physiology*; D001616:beta-Galactosidase / Q000378:metabolism*
D010713:Phosphatidylcholines; D013109:Sphingomyelins; D043322:Lactase; D001616:beta-Galactosidase