Supplementation of DHA-Rich Microalgal Oil or Fish Oil During the Suckling Period in Mildly n-3 Fatty Acid-Deficient Rat Pups

Long-chain polyunsaturated fatty acids (LC-PUFA), particularly arachidonic acid (ARA) and docosahexaenoic acid (DHA), are considered critical for the development of infants and are commonly supplemented in infant formulae. In this study, two common sources of n-3 LC-PUFA, fish oil (FO) and DHA-rich microalgal oil (DMO), were fed to rat pups of mildly n-3 PUFA-deficient dams to compare changes in LC-PUFA of tissue phospholipids. The milk from dams fed a n-3 PUFA-deficient diet contained less n-3 LC-PUFA than that of dams fed a control diet (AIN-93G). The pups' were given orally 1 mg/g weight of either FO or DMO for 17 days between the ages of 5 and 21 days, the pups were weaned, and sacrificed 1 week later for analysis of fatty acid compositions of brain, heart, kidney, spleen, and thymus phospholipids. Although both FO and DMO brought about a recovery in the tissue DHA levels compared to those of the control group (pups from AIN-93G-fed dams), DMO was more effective at restoring tissue LC-PUFA status because it was richer in DHA than FO. FO had a slightly lower PUFA level than that required to bring the LC-PUFA status completely to normal levels in this experiment, and EPA did not accumulate in tissues under the conditions tested here. These results demonstrate the effectiveness of ingesting either FO or DMO in the pre-weaning period for improving mild n-3 PUFA deficiency.     

A Maternal High Fat Diet Has Long‐Lasting Effects on Skeletal Muscle Lipid and PLIN Protein Content in Rat Offspring at Young Adulthood

A maternal high fat diet (HFD) can have adverse effects on skeletal muscle development. Skeletal muscle PLIN proteins (PLIN2, 3 and 5) are thought to play critical roles in lipid metabolism, however effects of HFD on PLIN and lipases (HSL, ATGL, CGI‐58) in mothers as well as their offspring have yet to be investigated. The primary objective of this study was to determine whether maternal HFD would influence skeletal muscle lipase and PLIN protein content in offspring at weaning (19d) and young adulthood (3mo). Female rats (28d old, n = 9/group) were fed control (CON, AIN93G, 7 % soybean oil) or HFD (AIN93G, 20 % lard) for 10 weeks prior to mating and throughout pregnancy and lactation. All offspring were weaned to CON [n = 18/group, 1 female and 1 male pup per litter were studied at weaning (19d) and 3mo of age]. There was no effect of sex for the main outcomes measured in plantaris, therefore male and female data was combined. Maternal HFD resulted in higher triacylglycerol content in pups at 3mo (p < 0.05), as well as in the dams (p = 0.015). Maternal HFD resulted in higher PLIN5 content in pups at weaning and 3mo (p = 0.05). PLIN2 and PLIN5 content decreased at 3mo versus weaning (p < 0.001). HFD dams had a higher PLIN3 content (p = 0.016). Diet had no effect on ATGL, CGI‐58, or HSL content. In conclusion, exposure to a maternal HFD resulted in higher skeletal muscle lipid and PLIN5 content in plantaris of offspring through to young adulthood.     

Dietary protein level during pregnancy. Its influence on maternal-fetal exchange of substrates

It is well known that the dietary protein level influences both the pregnancy process and development of the offspring. Therefore, a study was carried out to determine the effect that different protein percentages: 10%, 4% and 20% in diets administered to rats during pregnancy, had on food efficiency and on the substrates partition between rat dams and their neonates. Experimentation was thus carried out over a period of 21 days (pregnancy) and comparisons were made with well-nourished rats receiving 10% protein (controls) and between one and other group. Moreover, the effect on pregnancy was observed by comparing pregnant rats with non pregnant rats within each dietary situation. Food intake, weight parameters and food efficiency ratio were recorded in adult rats. Weight parameters were also evaluated in newborns. As results revealed, the highest the protein level in the diet, the highest the food efficiency ratio, both in the pregnant group and in the non pregnant group. Weight changes were determined in rat dams and their neonates, as a consequence of the different protein intakes. These also involved alterations in the substrates partition between the mothers and their offspring. Such findings might lead to the retention of substrates by the maternal tissues and, hence, to impairment of neonatal development.     

Modifying the n−3 fatty acid content of the maternal diet to determine the requirements of the fetal and suckling rat

During perinatal development, docosahexaenoic acid (22:6n−3) accumulates extensively in membrane phospholipids of the nervous system. To evaluate the n−3 fatty acid requirements of fetal and suckling rats, we investigated the accumulation of 22:6n−3 in the brain and liver of pup rats from birth to day 14 postpartum when their dams received increasing amounts of dietary 18:3n−3 (from 5 to 800 mg/100 g diet) during the pregnancy-lactation period. The fatty acid composition of brain and liver phospholipids of pups, as well as that of dam’s milk, was determined. At birth, brain 22:6n−3 increased regularly to reach the highest level when the maternal diet contained 800 mg 18:3n−3/100 g. On days 7 and 14 postpartum, brain 22:6n−3 plateaued at a maternal dietary supply of 200 mg/100 g. Docosapentaenoic acid (22:5n−6) had the opposite temporal pattern. The unusually high concentration of eicosapentaenoic acid (20:5n−3) in liver and dam’s milk observed at the highest 18:3n−3 intake suggests an excessive dietary supply of this fatty acid. All these data suggest that the n−3 fatty acid requirements of the pregnant rat are around 400 mg 18:3n−3 and those of the lactating rat at 200 mg (i.e., 0.9 and 0.45% of dietary energy, respectively). The values for 18:3n−3 and 22:6n−3 milk content which allowed brain 22:6n−3 to reach a plateau value in suckling pups were 1% of total fatty acids and 0.9% (colostrum) to 0.2% (mature milk), respectively. These levels are similar to those recommended for infant formulas.     

High Saturated Fat Diet Alters the Lipid Composition of Triacylglycerol and Polar Lipids in the Femur of Dam and Offspring Rats

Previous work has shown that dietary lipids alter femur lipid composition. Specifically, we have shown that exposure to high saturated fatty acid (SFA) diets in utero, during suckling, or post‐weaning alters femur total lipid composition, resulting in higher percent bone mass in males and females and bone mineral density (BMD) in female offspring with no effect on bone mineral outcomes in dams. Comparatively, high n‐3 polyunsaturated fatty acid (PUFA) diets increase femur polar (PL) lipid n‐3 content, which has been associated with increased bone mineral content and strength. However, the extent that PL or triacylglycerol (TAG) lipids change with high SFA diets is unknown. The current investigation examined the influence of a high SFA diet (20 % lard by weight) on femur PL and TAG lipid composition in 5‐month old female Wistar rats (fed high SFA diet from age 28 days onwards; dams) and their 19‐day old offspring (exposed to high SFA in utero and during suckling; pups). High SFA exposure resulted in increased monounsaturates and decreased n‐3 and n‐6 PUFA in the TAG fraction in both dams and pups, and higher SFA and n‐6:n‐3 ratio in dams only. The PL fraction showed decreased n‐6 PUFA in both dams and pups. The magnitude of the diet‐mediated responses, specifically TAG 18:1 and PL n‐6 PUFA, may have contributed to the previously reported altered BMD, which was supported with correlation analysis. Future research should investigate the relationship of diet‐induced changes in bone lipids on bone structure, as quantified through micro‐computed tomography.     

Fatty acid patterns in iron-deficient maternal and neonatal rats

To determine the effects of maternal iron deficiency on lipid composition and fatty acid patterns in offspring, rats were fed ad libitum diets containing 5 ppm iron (deficient) (n=8) or 320 ppm iron (control) (n=7) and deionized water from day-1 of gestation through day-18 of lactation. On day-2 of lactation, litters were standardized to three male and three female pups. On day-18, pups were fasted for 4 hr before tissue and blood collection. Significant changes in serum and liver lipid concentrations and fatty acid patterns were observed in deficient pups. Serum triglycerides, cholesterol and phospholipids and liver triglycerides, cholesterol, and cholesteryl esters were increased. In deficient pups, percentage total fatty acids of 14∶0, 16∶1, 18∶1, 18∶2 from serum lipids were increased; in liver, 14∶0, 18∶2, 18∶3 were increased; 18∶0 and 20∶4 were decreased in both serum and liver. Dam serum lipid levels did not differ between groups. Lipid changes observed in iron-deficient pups did not consistently reflect the milk, serum or liver lipid patterns observed in dams. Altered lipid composition and fatty acid patterns of iron-deficient pups thus appear to be of endogenous origin.     

Effects of postnatal ethanol exposure on brain growth and lipid composition in n−3 fatty acid-deficient and-adequate rats

The artificial rearing model was used to investigate the effects of short-term exposure to ethanol on growth and fatty acid composition of forebrain (FB) and cerebellum (CB) during the brain growth spurt in either n−3 fatty acid-adequate (AD) or n−3 deficient (DEF) rat pups. On postnatal day 5, offspring of female rats that had been fed AD or DEF diets from day 5 of life were assigned to three groups: members of two groups were gastrostomized and artificially fed formulas appropriate for their maternal history, and the third group (suckled control) was fostered to lactating dams of a similar dietary history. Half of the artificially reared pups in each dietary condition were fed ethanol in their formula (7% vol/vol) in one-quarter of their daily feedings, while the others received maltose-dextrin substituted isocalorically for ethanol. Blood alcohol concentrations did not differ betwen the dietary groups. FB weight on postnatal day 9 was lower in ethanol-exposed offspring in both dietary conditions. Brain fatty acid composition reflected dietary history in that, compared with AD pups, DEF pups had lower percentages of docosahexaenoic acid, higher percentages of 22∶5n−6, and a higher n−6/n−3 fatty acid ratio. However, the effects of ethanol exposure were inconsistent, lowering the n−6/n−3 ratio in the phosphatidylethanolamine (PF) fraction in FB but not in CB, while increasing this ratio in the phosphatidylcholine (PC) fraction in FB of the DEF pups only. Thus, while ethanol had some effects on lipid composition, there was no difference between the dietary groups in their vulnerability to the effects of early short-term ethanol exposure on brain growth.     

Increasing dietary linoleic acid in young rats increases and then decreases docosahexaenoic acid in retina but not in brain

The accumulation of fatty acids in retina, brain, liver, and plasma of 30-day-old rat pups consuming various levels of linoleic acid (LA, 18:2n-6) and constant α-linolenic acid (ALA, 18:3n-3) is reported. Dams were fed graded levels of LA during gestation and lactation, and the pups were maintained on the diet of their dams until the end of the brain growth spurt at 30 d of life. Milk, and pup brain, retina, liver, and plasma were analyzed quantitatively for fatty acid profile. The percentage of docosahexaenoic acid (DHA, 22:6n-3) in retina increased from an LA-deficient dietary level, peaked at the 9:1 (LA/ALA) level, then fell for the 41:1 and 69:1 levels. In contrast, the brain DHA percentage was unaffected by dietary LA levels. Retinal unsaturated fatty acid levels paralleled liver and plasma levels. The milk fatty acid composition mirrored the diets. These data show that the retinal fatty acid composition responds sensitively to dietary fatty acid composition, similar to liver and plasma, while the brain unsaturate composition is nearly independent of dietary composition.     

Maternal Flaxseed Oil During Lactation Enhances Bone Development in Male Rat Pups

Flaxseed oil is an alpha linolenic acid source important in the growth and body development stage; furthermore, this acid acts on adipose tissue and bone health. The aim of this study was to evaluate body composition, fatty acid composition, hormone profile, retroperitoneal adipocyte area and femur structure of pups at weaning, whose mothers were fed a diet containing flaxseed oil during lactation. After birth, pups were randomly assigned: control (C, n = 12) and flaxseed oil (FO, n = 12), rats whose mothers were treated with diet containing soybean or flaxseed oil. At 21 days, the pups were weaned and body mass, length, body composition, biochemical parameter, leptin, osteoprotegerin, osteocalcin, fatty acids composition, intra‐abdominal fat mass and femur structure were analyzed. FO showed (p < 0.05): higher body mass (+12 %) and length (+9 %); body fat mass (g, +45 %); bone mineral density (+8 %), bone mineral content (+55 %) and bone area (+35 %), osteocalcin (+173 %) and osteoprotegerin (+183 %). Arachidonic acid was lower (p < 0.0001), alpha‐linolenic and eicosapentaenoic were higher (p < 0.0001). Intra‐abdominal fat mass was higher (+25 %), however, the retroperitoneal adipocytes area was lower (?44 %). Femur mass (+10 %), distance between epiphyses (+4 %) and bone mineral density (+13 %) were higher. The study demonstrates that adequate flaxseed oil content during a lactation diet plays an important role in the development of pups.     

Maternal Dietary Fat Affects Milk Fatty Acid Profile and Impacts on Weight Gain and Thermogenic Capacity of Suckling Rats

We aimed to assess the effects of maternal supplementation with the main fat sources used in the human Western diet (olive oil, butter, margarine) on milk FA composition and on plasma FA profile of offspring, and to determine whether it may influence body-weight-gain (BWG) and adiposity of offspring during the suckling period. Wistar rats were supplemented with the different fat sources from day 14 of gestation and throughout lactation. Olive oil-supplemented dams showed the highest proportion of oleic-acid in milk, with no changes in plasma. Their offspring also showed the highest proportion of this FA in plasma, lower BWG during the suckling period, and higher levels of UCP1 in brown adipose tissue (BAT) at weaning. Margarine-supplemented dams showed the highest percentage of PUFA in milk, and a similar tendency was found in plasma of their offspring. Butter-supplemented dams displayed higher proportion of saturated FA (SFA) in milk compared to other fat-supplemented dams, but lower than controls. Control offspring also showed higher proportion of SFA in plasma and greater BWG during the suckling period than fat-supplemented groups. Significant correlations were found between the relative content of some milk FA and BWG of offspring, in particular, oleic-acid levels correlated negatively with BWG and positively with UCP1 levels. These results show that maternal dietary source of fat affects milk FA composition and circulating FA profile, as could be expected, but also BWG and thermogenic capacity of offspring during the suckling period. An effect of oleic-acid stimulating BAT thermogenic capacity of suckling pups is proposed.     

High dietary 18∶3n−3 increases the 18∶3n−3 but not the 22∶6n−3 content in the whole body, brain, skin, epididymal fat pads, and muscles of suckling rat pups

The objective of this study was to test the hypothesis that increasing maternal dietary 18∶3n−3 by decreasing the 18∶2n−6/18∶3n−3 ratio will increase the 18∶3n−3 and 22∶6n−3 content of the whole body, liver, skin (epidermis, dermis, and subcutaneous tissue), epididymal fat pads, and muscles (arms and legs) of 2-wk-old rat pups. Sprague-Dawley dams at parturition were fed semipurified diets containing either a low (18∶2n−6 to 18∶3n−3 ratio of 24.7∶1) or a high (18∶2n−6 to 18∶3n−3 ratio of 1.0∶1) 18∶3n−3 fatty acid content. During the first 2 wk of life, rat pups received only their dams' milk. Fatty acid composition of the pups' stomach contents (dams' milk), whole body, brain, liver, skin, epididymal fat pads, and muscles was determined. The stomach fatty acid composition of 18∶3n−3 reflected the dams' diet. The content of 18∶3n−3 in whole body, brain, liver, skin, epididymal fat pads, and muscles was significantly (P<0.05) greater in rat pups fed the high compared with the low 18∶3n−3 fatty acid diet. The 22∶6n−3 content of the whole body, brain, skin, epididymal fat pads, and muscles was not quantitatively different in rat pups fed either the low or high 18∶3n−3 fatty acid diet. The 20∶5n−3 and 22∶5n−3 content of the whole body, skin, and epididymal fat pads was significantly increased in rat pups fed the high compared with the low 18∶3n−3 fatty acid diet. High content of 18∶3n−3 was found in the skin of rat pups fed either a low or high 18∶3n−3 fatty acid diet. These findings demonstrate that high maternal dietary 18∶3n−3 significantly increases the 18∶3n−3 but not the 22∶6n−3 content of the whole body, brain, skin, epididymal fat pads, and muscles with approximately 39 and 41% of the whole body 18∶3n−3 content being deposited in the skin of suckling rat pups fed either the low or high 18∶3n−3 diet, respectively.     

Maternal Intake of Fish Oil but not of Linseed Oil Reduces the Antibody Response in Neonatal Mice

Dietary levels of n-3 PUFA are believed to influence the immune system. The importance of the source of n-3 PUFA is debated. This study addressed how the content and source of n-3 PUFA in the maternal diet influenced tissue FA composition and the immune response to ovalbumin (OVA) in mice pups. From the day of conception and throughout lactation, dams were fed diets containing 4% fat from linseed oil (LSO), fish oil (FO) or a n-3 PUFA-deficient diet (DEF). Pups were injected with OVA within 24 h of birth and sacrificed at weaning (day 21). Overall, the content of n-3 PUFA in milk, liver and spleen reflected the source and only minor differences were observed in brain phospholipid 22:6n-3. The source had only limited influence on the n-3 PUFA accretion in peripheral tissue, with most pronounced differences in the spleen. The marine PUFA-group had reduced levels of total OVA-specific antibodies and OVA-IgG1 titers in the pup blood, while the response in the LSO-group did not differ from that in the DEF-group. There were no statistical differences in the cytokine responses to OVA-stimulated splenocytes, but the decrease in IgG1 was paralleled by an increase in IFNγ-production and a decrease in IL-6-production. Our results indicate that maternal intake of FO, but not of LSO, changes the offspring’s antigen-specific response and potentially increases Th1-polarization.     

Effects of a Westernized Diet on the Reflexes and Physical Maturation of Male Rat Offspring During the Perinatal Period

This study evaluates the effects of a westernized diet during the perinatal period on the maternal performance and growth and development of rat offspring. Female Wistar rats were fed with either a control (C) diet, with casein as the protein source or a westernized (W) diet, during pregnancy and lactation. The pups were divided, eight per group, into the same diet groups as their dams. During lactation, the body weight (day 1, W = 6.85 ± 0.62 g, C = 5.81 ± 0.49, p < 0.05; day 21, W = 55.42 ± 3.78, C = 47.75 ± 3.45, p < 0.001) and somatic growth (body length day 1, W = 53.24 ± 2.16, C = 50.641 ± 1.79, p < 0.05; day 21, W = 124.8, C = 119.903 ± 3.71, p < 0.001) in the male offspring showed significant differences among the groups. The physical appearance and reflex maturation showed differences between day 1 and day 3. With the westernized diet, during the perinatal period, no alterations in maternal weight gain, gestation or performance were observed; however, changes in the coefficients of feed efficiency and energy during lactation were noted. Besides, blood glucose was found to be elevated at the end of lactation (C = 3.67 ± 0.35 mmol/l, W = 5.2 0 ± 0.49 mmol/l). At 21 days, the male pups from the dams on the westernized diet were 15 % heavier, and the maturation of the neural reflexes and physical characteristics were found to occur earlier. Therefore, the consumption of a westernized diet during the perinatal period was independent of maternal energy intake, and influenced the growth and development of offspring.     

Cyclopenta[d]pyrimidines and dihydropyrrolo[2,3-d]pyrimidines as potent and selective corticotropin-releasing factor 1 receptor antagonists

Two new classes of potent and selective CRF(1) receptor antagonists are presented. Exploration of general templates 3 and 4 through modifications of the top amine and bottom phenyl substituents led to optimization of the in vitro affinity and pharmacokinetic profiles. The typical alkyl chains present in the top region of CRF(1) antagonists were replaced by substituted heteroaryl moieties, leading to a dramatic improvement of the metabolic stability. This improvement was apparent when the compounds were dosed in vivo: several compounds exhibited low plasma clearance, good oral bioavailability, and high brain penetration. As a consequence of their outstanding pharmacokinetic profiles, these CRF(1) antagonists, as exemplified by compound 4 fi (4-(4-bromo-3-methyl-1H-pyrazol-1-yl)-7-(2,4-dichlorophenyl)-2-methyl-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidine), produced a dose-dependent "anxiolytic-like" effect when administered orally, decreasing the vocalization of rat pups.     

Effects of feeding Lunaria oil rich in nervonic and erucic acids on the fatty acid compositions of sphingomyelins from erythrocytes, liver, and brain of the quaking mouse mutant

Feeding an oil from Lunaria biennis rich in 22∶1n−9 and 24∶1n−9 to homozygous quaking (qk.qk) mice caused a large increase in the percentage of 24∶1n−9 and corresponding decreases in the percentage of 24∶0 and 22∶0 in sphingomyelins from liver, erythrocytes, and milk. Brain sphingomyelin from 2-wk-old qk.qk pups born to qk.qk mothers maintained on the Lunaria oil had essentially normal percentage of 24∶1n−9 and 18∶0, in contrast to pups born to mothers maintained on a control oil rich in 18∶1n−9 whose brain sphingomyelin had a markedly reduced percentage of 24∶1n−9 and an increased percentage of 18∶0. After 2 wk and up to and beyond weaning, the qk.qk pups from Lunaria-fed mothers weaned on to the Lunaria diet had a markedly decreased percentage of 24∶1n−9 in their brain sphingomyelin, accompanied by an increased percentage of 18∶0, as compared to heterozygous quaking mice. However, the percentage of 24∶1n−9 in brain sphingomyelin in qk.qk pups weaned on to the Lunaria diet continued throughout this period (2–8 wk postbirth) to be significantly higher than in qk.qk pups weaned on to the control diet. We conclude that dietary 24∶1n−9 influences the fatty acid composition of brain sphingomyelin in qk.qk mice, but only via the mother in pre- or early postnatal animals. We further consider that the dietary effects may be elicited mainly in the sphingomyelin of nonmyelinated brain cells, and that the nervonic acid in myelin sphingomyelin may be formed mainly by chain elongation in oligodendrocytes from shorter chain fatty acid precursors.     

Additive effects of protein malnutrition and cortisol on plasma proteins and immunoglobulins of pregnant rats, and their offsprings

This research work was carried out to study the effects of two immunosuppressive mechanisms: protein malnutrition and cortisol treatment on the feto-maternal unit. Therefore, plasma Ig G and Ig M levels were tested in pregnant rats submitted to a low protein diet (4%) and cortisol treatment (0.5 mg/100 g b.w.) during pregnancy and in their offspring. Nutritional status was evaluated by measuring ponderal parameters and plasma protein levels in rat dams and their neonates. Thus, a fall in ponderal parameters and in plasma protein levels was observed, both in rat dams suffering protein malnutrition as well as in their newborns. Cortisol treatment produced a decrease in the ponderal parameters of the control group, and an increase in plasma protein levels of the malnourished one, both in rat dams and in their neonates. Apparently, protein malnutrition might lead to a low functionality of B lymphocytes, caused by a decrease in Ig G and Ig M rates of malnourished rat dams. Ig M levels, however, increased in neonates as a consequence of possible concomitant infections. Cortisol treatment promoted humoral immune deficiency, since Ig G and Ig M levels decreased both in the control and in the malnourished pregnant rat groups. Nevertheless, cortisol administration seemed to increase susceptibility to infection in the newborns, especially in those born from malnourished rat dams.     

Effect of specific dietary fatty acids on lipogenesis in the livers and mammary glands of lactating mice

The effects of linoleic, linolenic and columbinic acids fed as 4% of a high carbohydrate (50% glucose) diet on the activities and the amounts of several enzymes associated with fatty acid synthesis in livers and mammary glands of lactating mice were compared with those for stearic and oleic acids. Fatty acid synthesis, measured in vivo, was significantly lower in livers of mice ingesting all 3 polyunsaturated fatty acids (PUFA), whereas in mammary glands synthesis was lower only in mice receiving columbinic acid. The activities of fatty acid synthetase (FAS) and acetyl CoA carboxylase were significantly reduced in liver by all 3 PUFA, as were activities of glucose-6-phosphate dehydrogenase, malic enzyme (ME) and citrate cleavage enzyme (CCE), also associated with lipogenesis. In mammary gland, on the other hand, the activities of these enzymes were unaffected by dietary PUFA. The tissue contents of FAS, ME and CCE, measured by rocket immunoelectrophoresis, were found to be significantly reduced in liver by linoleate, linolenate and columbinate but were not significantly altered in mammary gland. The decrease in hepatic lipogenesis observed was principally due to a decrease in the amounts of these enzymes induced by the dietary PUFA but the inhibition in mammary gland caused by columbinate could not be accounted for by a reduction in enzyme contents and therefore may be due to allosteric effects which occur when fatty acid synthesis is measured with³H₂O. The fatty acid composition in liver and mammary gland of dams and in liver and kidney of pups completely reflected dietary fatty acids. Columbinate made up ca. 20% of the total fatty acids in both tissues of the columbinic acid-fed mice and ca. 15% in the pup tissues. This suggests that columbinate is incorporated into milk lipids of dams and is easily absorbed by pups. The elevated ratios of 16/16∶1 and 18/18∶1 in liver and mammary gland of dams and liver and kidney of the pups from dams fed linoleate, linolenate and columbinate suggest that each of these polyunsaturated fatty acids in the diet can inhibit the activity of Δ9 desaturase.     

Mammary transfer and metabolism in the rat of halogenated fatty acids of halogenated olive oil

To assess possible incorporation of halogenated fatty acids into the neonate via the milk, a 4-day study was carried out in which lactating Wistar rats were orally dosed with either brominated olive oil (BOO) (0.6 g/kg body wt/day) or chlorinated olive oil (COO) (0.4 g/kg body wt/day) for the first 4 days. On days 1–5 inclusive 2 pups per litter were sacrificed and the stomach curd and livers analyzed for halogenated fatty acids by gas liquid chromatography (GLC). On day 5 all dams also were sacrificed and their livers and adipose tissue similarly analyzed. With BOO, brominated fatty acids (bfa) accumulated in both the milk lipids and neonate liver lipids, and appeared to plateau on day 4 at levels of 2% and 5% respectively. In contrast to the BOO in which approximately 100% of the bfa was dibromostearis (DBS), the milk bfa comprised 79% (DBS), 9% dibromopalmitic (DBP) and 12% dibromomyristic (DBM) acids, suggesting maternal metabolism to the shorter chain brominated acids. In the neonate liver lipids the bfa composition was 47% (DBS), 12% (DBP) and 41% (DBM), suggesting either further metabolism in the neonate and/or preferential accumulation of the shorter chain brominated acids. The analysis of maternal tissue indicated very low bfa residues, contrary to previous studies in non-lactating rats. Similar results were obtained with COO.     

Effects of cholesterol feeding to maternal rats on metabolism of cholesterol and bile acids in the dams and their offspring

The influence of feeding cholesterol to rats during pregnancy and postpartum (from the 11th day of gestation to the third day after delivery) on the serum and hepatic cholesterol levels and on the bile acid composition in the pool and in the liver in relationship to the dams and their pups was examined. The hepatic content of cholesterol in both dam and offspring increased during cholesterol feeding without any changes in serum cholesterol level. In the dams, mainly the esterified cholesterol was increased; in the pups, mainly the free cholesterol was increased. Cholesterol feeding led to a pronounced increase in the pool of β-muricholic acid and a relative decrease in the lithocholic acid concentration in pregnant rats. In fetal rats, the chenodeoxycholic acid pool was increased by cholesterol intake. The lithocholic acid pool was larger in the postpartum rats fed cholesterol than in the controls, while the concentration of α- and β-muricholic acids was decreased. The neonates of cholesterol-fed dams had a larger pool of chenodeoxycholic acid but a smaller pool of β-muricholic acid. These results suggest that the metabolism of cholesterol and of bile acids in dams and their offspring respond differently to cholesterol intake.