Hiroki Suganuma

Maternal docosahexaenoic acid-enriched diet prevents neonatal brain injury.

Hypoxic‐ischemic encephalopathy due to neonatal asphyxia is one of the most important causes of delayed neurological development. Prolonged neuronal apoptosis plays an important role in the processes contributing to neuronal degeneration. Docosahexaenoic acid (DHA), a major component of brain membrane phospholipids, prevents neuronal cell apoptosis and plays an important role as an anti‐oxidant agent. We investigated the neuroprotective and anti‐oxidant effects of maternal DHA supplementation during pregnancy in a model of neonatal hypoxic‐ischemic encephalopathy. Pregnant rats were randomly assigned to two experimental groups: a control group or a DHA‐enriched diet group. Hypoxic‐ischemic encephalopathy was produced by left common carotid artery occlusion and exposure to 8% oxygen for 1.5 h. TUNEL assay, immunohistochemistry for caspase‐3 and 8‐hydroxy‐deoxyguanosine (8‐OHdG), and Western blot for caspase‐3 were performed at postnatal days 8, 10 and 14. Fatty acid composition of brain was estimated on postnatal day 7. Maternal diet clearly influenced brain fatty acid composition in pups. Numbers of apoptotic neuronal cells and 8‐OHdG immunoreactivity were significantly decreased in the DHA‐enriched group. Our findings indicate that maternal DHA‐enriched diet during pregnancy provides neuroprotection by inhibiting oxidative stress and apoptotic neuronal death. Dietary supplementation of DHA during pregnancy may thus be beneficial in preventing neonatal brain injury.

IGF-I, leptin and active ghrelin levels in very low birth weight infants during the first 8 weeks of life

Aim:  We investigated the relationship between plasma insulin‐like growth factor I (IGF‐I), leptin, active ghrelin levels, and postnatal growth in very low birth weight (VLBW) infants.

Plasma levels of active ghrelin until 8 weeks after birth in preterm infants: relationship with anthropometric and biochemical measures

This study investigated the relationship between plasma levels of ghrelin and postnatal growth in preterm infants. The levels of active ghrelin in cord blood and in plasma in 25 very low birthweight (VLBW) infants were measured. The results indicate that the levels of circulating active ghrelin markedly increases after birth in VLBW infants, and suggest that the increased levels of ghrelin reflects the maturation of ghrelin production in the stomach and an increased physiological need for ghrelin.

Effects of breastfeeding on the risk factors for metabolic syndrome in preterm infants.

Evidence suggests that breastfeeding during infancy lowers the risk of metabolic syndrome (MS) and its attendant risk factors in adult life. To investigate the influence of feeding type on the risk factors of MS, we assessed insulin sensitivity and lipid and apolipoprotein metabolism in preterm infants. Blood samples were collected from preterm infants at the time of discharge. Infants were separated into two groups: a breast milk (BM) group receiving ⩾90% of their intake from BM, and a mixed-fed (MF) group receiving ⩾50% of their intake from formula. The following indices were then compared between the two groups. Blood glucose and serum insulin levels were used to calculate the quantitative insulin sensitivity check index (QUICKI). We also measured serum total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), apolipoprotein-A1 (apoA1) and apolipoprotein-B (apoB) levels, and the ratios of TC/HDLc, LDLc/HDLc and apoB/apoA1. The mean gestational age was 32.9 weeks at birth, and blood samples were collected at a mean corrected age of 37.4 weeks. There were 22 infants in the BM group and 19 in the MF group. QUICKI was significantly higher in the BM group. TC, HDLc and apoA1 were not significantly different between the groups, but LDLc and apoB levels were significantly higher in the BM group. The TC/HDLc, LDLc/HDLc and apoB/apoA1 ratios were significantly higher in the BM group. In preterm infants, the type of feeding exposure in the early postnatal period may influence glucose, lipid and apolipoprotein metabolism, and affect markers of MS.

Oxidative stress early in infancy and neurodevelopmental outcome in very low‐birthweight infants

Reactive oxygen species may be involved in serious diseases in premature infants. The objective of this study was to assess the relationship between neurodevelopmental outcome and oxidative stress marker level in the urine of very low‐birthweight (VLBW) infants.

Lipid profile and atherogenic indices soon after birth in Japanese preterm infants.

The intra‐uterine environment affects the risk of development of cardiovascular disease in adulthood. The aim of this study was to determine the influence of prematurity and foetal growth restriction on lipid metabolism, by assessing atherogenic indices soon after birth in preterm infants.

Effect of Hypoxic-Ischemic Insults on the Composition of Fatty Acids in the Brain of Neonatal Rats

Background: Long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (DHA; 22:6 n–3), comprise a major component of brain membrane phospholipids. The effect of neonatal hypoxic-ischemic insults on brain fatty acid composition is not completely understood. The aim of this study was to investigate alterations in brain fatty acid composition during development and in response to hypoxic-ischemic insults in neonatal rats. Methods: Postnatal day 7 pups were randomly assigned to two experimental groups: a control group or a hypoxic-ischemic group in which hypoxia-ischemia was produced by left common carotid artery occlusion and exposure to 8% oxygen for 1.5 h. Various brain fatty acids were measured on postnatal days 8, 10 and 14. Results: On postnatal day 14, the ratio of DHA to total fatty acids increased in the control group, but not in the hypoxic-ischemic group (p < 0.05). We observed no significant differences in arachidonic acid content in the brain between the two groups. Conclusions: These results suggest that hypoxic-ischemic insults interfere with accumulation of brain DHA in developing rats. DHA supplementation may be beneficial for treating neonatal hypoxic-ischemic encephalopathy.

Effects of parenteral soybean oil lipid emulsion on the long-chain polyunsaturated fatty acid profile in very-low-birth-weight infants

Aim:  Conventional soybean lipid emulsions contain no docosahexaenoic acid (DHA) or arachidonic acid (AA). We investigated the relationship between blood DHA and AA status in 27 very‐low‐birth‐weight (VLBW) infants with or without parenteral lipid emulsion.

Recurrent meningitis with Mondini dysplasia after the operation and vaccination.

Several congenital diseases can cause recurrent meningitis, including immunodeficiency and cerebrospinal fluid (CSF) leakage. Mondini dysplasia, an inner ear malformation with cochlear dysplasia, can also be accompanied by CSF leakage, which occasionally causes recurrent meningitis via the auditory tube. We report the case of a girl with Mondini dysplasia who experienced three episodes of pneumococcal meningitis despite undergoing definitive operation and pneumococcal polysaccharide vaccination.

Fatty acid composition of the brain of intrauterine growth retardation rats and the effect of maternal docosahexaenoic acid enriched diet

AIM To determine whether the intrauterine environment affects lipid metabolism, we measured the fatty acid composition of the brain in rats with intrauterine growth retardation (IUGR) induced by synthetic thromboxane A2 (STA2). Additionally, we evaluated the effect of maternal docosahexaenoic acid (DHA)-enriched diet. METHODS Two experimental diets were provided: soy bean oil and DHA-enriched diets. Maternal rats were divided randomly into three groups, STA2-/Soy (Sham), STA2+/Soy (IUGR), and STA2+/DHA (DHA) groups. The Sham and IUGR groups were fed the soy diet, and the DHA group received the DHA-enriched diet from embryonic day 7 until delivery. On postnatal days 1 and 7, the pups were weighed and their brains were removed for lipid analysis. RESULTS The body weight of the IUGR and DHA groups was significantly less than that of the Sham group both on the postnatal days 1 and 7, whereas it was not significantly different between the IUGR and DHA groups either on postnatal day 1 or day 7. There was no significant difference in the percentage of DHA between the Sham and IUGR groups either on postnatal day 1 or 7. On the other hand, the percentage of DHA was higher in the DHA group than in the IUGR group both on the postnatal days 1 and 7. CONCLUSIONS The fatty acid composition in the brain was not altered in the STA2-induced IUGR rat model. Increased DHA percentage was observed in the maternal DHA-enriched diet group, although no beneficial effect on body weight gain was observed.