Long-chain polyunsaturated fatty acid (LCP) levels in brain and red blood cells of neonatal rats fed LCP-supplemented formulae

Poster Presentations Tuesday 22 July

EFA & Eicosanoids 1997- Edinburgh

P85

P86

Long-Chain Polyunsaturated Fatty Acid (LCP) Levels in Brain and Red Blood Cells of Neonatal Rats Fed LCP-Supplemented Formulae.

PARITY EFFECT ON ESSENTIAL FATTY ACID STATUS IN HEALTHY HISPANIC MOTHERS AND INFANTS. Betty Bernard, Laura Sergis, Linda Chan, Ralph T. Holman, Dept. of Pediatrics, Univ. of Southern California, Los Angeles, CA, USA

G Ward I Y-S Huang2, E Bobik 2, H-C Xing I, L Mutsaers t, N Auestad 2, M Montalto 2 & P Wainwright l. IUniv. of Waterloo, Dept of Health Studies & Gerontology, Waterloo, Ontario, CAN; & 2Ross Laboratories, Columbus, Ohio, USA. We used the artificial rearing method to "formula-feed" infant rats and study the relationship between fonuula LCP content and the fatty acid composition of the brain and red blood cells (RBC). The brain of an infant rat is at a stage of development similar to that of the premature human infant. We gastrostomized rat pups at 5 days of age and reared them until day 18 with rat milk-substitutes containing I0% linoleic acid and 1% alpha-linolenic acid (g/100g fat), and, using a 2 X 2 factorial design, one of three levels of arachidonic acid (AA) (0.0%, 0.4%, and 2.4% of fatty acids) and doeosahexaenoic acid (DHA) (0.0%, 0.4%, and 2.4% of fatty acids). A tenth group was reared by nursing dams fed a standard AIN-93M chow. AA and DHA were added as single ceil microbial oils (Martek Bioscienees, Corp., Columbia, MD). The phosphatidylethanolamine (PE) fatty acid composition of the brain reflected the dietary composition in that the long-chain supplementation led to increases in tissue concentrations of AA and DHA (main effects for both AA and DHA, p < 0.0001). Furthermore, AA supplementation led to reduced concentrations of DHA (main effect, p < 0.0001) while DHA supplementation reduced concentrations of AA (main effect, p < 0.0001). The effects on the cerebellum were greater than were those on the forebrain. Relative to the unsupplemented baseline group (0% AA/0% DHA), the range of AA levels was 87 - 110% in the forebrain and 77 to 112% in the cerebellum; the corresponding range of DHA levels was 82 - 141% in the forebrain and 78 - 153% in the cerebellum. In RBC PE, the range in AA of 68 - 113% was similar to brain, whereas the range in DHA of 63 - 286% was much greater than that seen in brain. The functional significance of these changes in terms of behavioral effects remains to be determined. The results of this study support the use of the artificial rearing model in the infant rat to address the effects of LCP supplementation in infant formulae.

235

To investigate whether increased parity puts the fetus at risk for an essential fatty acid (EFA) deficiency, 30 pairs of healthy mothers and their full-term infants - 15 primiparous (P) & 15 multiparous (M) of >-3 gravida) - were studied at delivery for total plasma lipid profiles by GLC, clinical data, and anthropometric measurements. Baby Morn ~Bahy Morn Bah) VIum 18:2 18:2[20:3 20:3 20:4 2 0 : 4 Primip:%FAdetectedin 100 100 80 93 1 0 0 100 MeanFA%ofplasmaFA 6 . 6 1 1 1 9 . 6 0 . 8 5 0 . 5 3 7 . 1 1 3 . 8 8 M u l t i p : % F A d c t c c t e d i n 100 i f 0 0 80 77 100 100 w6 Fatty Acids (FA)

I

MeanFA%ofplasmaFA

6.66118.8

w3 & 20:3W9 FA Primip:%FAdetectedin MeanFA%ofplasmaFA

18:3

Multip:%FAdeteetedin MeanFA%ofplasmaFA

73

1

0.98 7.2;

8aby[Mom 22:5 22:5 53 40 0.06 0.05 21 60 3.42 0.14 0.04

18:3120:5 20:5122:6122:6120t3 20t3 ll00

60

73

73

86

47

13

0.11 0.35 0.22 0.07 0.52 0.53 1.14 0.04 67 100 20 38 1001 8 9 33 23 0 . 0 8 0 . 2 9 1.87 0 . 0 7 0 , 6 9 0 . 6 1 0 . 1 3 0 . 1 7

P vs. M for EFA detection or the EFA % of total plasma lipids in mother and baby did not reach significance (Yates corrected Chi Sq). P infants differed significantly only for lesser mean weights of P 3324 vs. M 3660 gins, and a smalter head circumference P 34.52 vs. M 35.65 cm, but no significant differences of P vs. M for EFA in the babies and mothers. Gradients for EFA favoring the fetus are found in all of the infants for 20:4 w6 and 20:5w3 - both important EFA in structural brain lipids and E2, E3 eicosanoid production. The marginal EFA status found in these clinically healthy gravid P & M women and their infants could well be benefited by an increased balanced dietary EFA supplementation of both w6 & w3 fatty acids.

P87

P88

The Effects of Long-Ghain Polyunsaturated Fatty Acids on Infant Habituation at 3 Months and Problem-Solving at 9 Months P. Willatts I , J.S. Forsyth 2, M.K. DiModugno 1, S. V a r m a 2, M. Colvin 2 Dcpts of Psychology I & Child Health 2, University of Dundee, Dundee, Scotland, UK.

ENRICHMENT OF INFANT FORMUI,A WITH LONG CtlAIN POI.YUNSATtJRATEI) FATTY ACIDS. St)ME EFFECTS ()N IMMIJNE SYSTEM. VARELA P . G A R C i A - G A R C i A P. Institute de Nutricidn (CSICUCM/. Facultad de Farmacia. Ciudad Universitaria. 28040 Madrid. Spain.

Infants in the first months of life have limited ability to synthesise long-chain polyuusattwated fatty acids (LCPUFA) and rely on a dietary supply. L C P U F A are present in breast milk, but until recently have been absent from artificial formulas. To determine whether this relative deficiency of L C P U F A in formula fed infants m a y have important functional consequences, we undertook a randomiscd prospective study o f the relationship of L C P U F A to infant cognitive bohaviour. 58 healthy, term infants were ranflomiscd to a formula supplemented with L C P U F A or a formula lacking LCPUFA. Infant cognitive function was assessed at 3 months using visual habituation measures which reflect the infant's efficiency at processing information. Cognitive function at 9 months was assessed using measures o f means-end problem solving which is described as the planned execution o f a sequence o f actions to achieve a goal. Measures o f total fixation time on habituation, and performance on means-end problem solving have been shown to correlate with childhood IQ scores. Infants receiving L C P U F A had shorter total fixation times and higher problem solving scores in comparison to the NUn-LCPUFA group, but the differences were not significant in this sample. H a l f the infants in both groups demonstrated a late peak fixation during habituation, which is cousidered to indicate poor attention control. Among infants with late peak fixations, those who received LCPUFA had a significantly reduced total fixation time at 3 months (95.5(85.2) v 211.8(139.3), p<0.01), and significantly more problem sointious at 9 months (1.9(1.6) v 0.6(0.7), p<0.05). Growth parameters taken at birth o f the late peakers were significantly less than the early peakers. These findings suggest that term infants with evidence o f intrauterine growth retardation m a y have impaired attention control. In these infants, supplementation o f L C P U F A m a y r'~'ult in improved visual information processing and problem solving. Because measures of infant habituation and problem solving predict childhood IQ scores, supplementation with L C P U F A m a y have implications for the development o f childhood intelligence. This study was sponsored by Mihipa Ltd (UK).

Long-chain polyunsaturated fatty acids/LCP), especially eicosapentaenoic acid (FPA), arachidonic acid (AA). and docoxahexaenoie acid (DHA) are semi-essential during the neonatal period. It is may due to the important effects on neural development of infants and on immunucompetence through out the eicosanoids synthesis In this sense, it has been recommended that infant formulas should contain LCP in similar amounts to those of human milk. There are many researchs in relation with preterm infants and neural development, but the knouledges about the effects of these l\~rmulas on immune system are more scarce. The aim of this work ,,',as to stud?. the effects of enrichment LCP infant formulas on gro',;th and some aspects of immunocumpetence in an experimental model. Eighteen ueanling male Wistar rats were used and divided into three groups, depending on the diet supplied: l/ Control (C). 2) Diet based in an infant formula non enriched with LCP (F) and 3) Diet based in an infant tbrmula enriched v, ith LCP (FE). The diets (isocaloric) *',ere administered during 28 d. On day 23, the immune responses were tested against sheep erythrocytes (SRBC). Body ,,','eight, teed consumption as well as spleen weight, spleen cells count and number of splenic plasma ceils secreting antiSRBC antibodies (direct plaque forming cells: DPFC) were assessed. Final weight, weight gain and teed comsuption were higher in the C group than in both F and FE. The experimental diets did not modit~ spleen v, eight. although spleen weight/body weight ratio in group F was 19% greater than those found in C group. When spleen F and FE lymphocytes count results were compared with C data. no statistical differences ,acre observed: howexer these values were higher in F group than in FE. The number of DPFC, both in absolute terms and when expressed per 10e spleen cells, was similar in FE and C groups, v, hilst F group showed increased levels in relation v, ith FE one. In conclusion, the tv, o experimental diets are not more adequate for rat growth, as might have been expected. The diet that contain LCP promoted an immunological response similar to that produced bv diet C and lov.er than F diet. in our experimental conditions.