Unlocking the power of Lactoferrin: Exploring its role in early life and its preventive potential for adult chronic diseases

Nutrition during the early postnatal period exerts a profound impact on both infant development and later-life health. Breast milk, which contains lactoferrin, a dynamic protein, plays a crucial role in the growth of various biological systems and in preventing numerous chronic diseases. Based on the relationship between early infant development and chronic diseases later in life, this paper presents a review of the effects of lactoferrin in early life on neonates intestinal tract, immune system, nervous system, adipocyte development, and early intestinal microflora establishment, as well as the preventive and potential mechanisms of early postnatal lactoferrin against adult allergy, inflammatory bowel disease, depression, cancer, and obesity. Furthermore, we summarized the application status of lactoferrin in the early postnatal period and suggested directions for future research.

Feasibility of automated early postnatal sleep staging in extremely and very preterm neonates using dual-channel EEG

OBJECTIVE

To investigate the feasibility of automated sleep staging based on quantitative analysis of dual-channel electroencephalography (EEG) for extremely and very preterm infants during their first postnatal days.

METHODS

We enrolled 17 preterm neonates born between 25 and 30 weeks of gestational age. Three-hour behavioral sleep observations and simultaneous dual-channel EEG monitoring were conducted for each infant within their first 72 hours after birth. Four kinds of representative and complementary quantitative EEG (qEEG) metrics (i.e., bursting, synchrony, spectral power, and complexity) were calculated and compared between active sleep, quiet sleep, and wakefulness. All analyses were performed in offline mode.

RESULTS

In separate comparison analyses, significant differences between sleep-wake states were found for bursting, spectral power and complexity features. The automated sleep-wake state classifier based on the combination of all qEEG features achieved a macro-averaged area under the curve of receiver operating characteristic of 74.8%. The complexity features contributed the most to sleep-wake state classification.

CONCLUSIONS

It is feasible to distinguish between sleep-wake states within the first 72 postnatal hours for extremely and very preterm infants using qEEG metrics.

SIGNIFICANCE

Our findings offer the possibility of starting personalized care dependent on preterm infants' sleep-wake states directly after birth, potentially yielding long-run benefits for their developmental outcomes.

Early postnatal allergic airway inflammation induces dystrophic microglia leading to excitatory postsynaptic surplus and autism-like behavior

Microglia play key roles in synaptic pruning, which primarily occurs from the postnatal period to adolescence. Synaptic pruning is essential for normal brain development and its impairment is implicated in neuropsychiatric developmental diseases such as autism spectrum disorders (ASD). Recent epidemiological surveys reported a strong link between ASD and atopic/allergic diseases. However, few studies have experimentally investigated the relationship between allergy and ASD-like manifestations, particularly in the early postnatal period, when allergic disorders occur frequently. Therefore, we aimed to characterize how allergic inflammation in the early postnatal period influences microglia and behavior using mouse models of short- and long-term airway allergy. Male mice were immunized by an intraperitoneal injection of aluminum hydroxide and ovalbumin (OVA) or phosphate-buffered saline (control) on postnatal days (P) 3, 7, and 11, followed by intranasal challenge with OVA or phosphate-buffered saline solution twice a week until P30 or P70. In the hippocampus, Iba-1-positive areas, the size of Iba-1-positive microglial cell bodies, and the ramification index of microglia by Sholl analysis were significantly smaller in the OVA group than in the control group on P30 and P70, although Iba-1-positive microglia numbers did not differ significantly between the two groups. In Iba-1-positive cells, postsynaptic density protein 95 (PSD95)-occupied areas and CD68-occupied areas were significantly decreased on P30 and P70, respectively, in the OVA group compared with the control group. Immunoblotting using hippocampal tissues demonstrated that amounts of PSD95, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor 2, and N-methyl-D-aspartate (NMDA) receptor 2B were significantly increased in the OVA group compared with the control group on P70, and a similar increasing trend for PSD95 was observed on P30. Neurogenesis was not significantly different between the two groups on P30 or P70 by doublecortin immunohistochemistry. The social preference index was significantly lower in the three chamber test and the number of buried marbles was significantly higher in the OVA group than in the control group on P70 but not on P30, whereas locomotion and anxiety were not different between the two groups. Compared with the control group, serum basal corticosterone levels were significantly elevated and hippocampal glucocorticoid receptor (GR) amounts and nuclear GR translocation in microglia, but not in neurons or astrocytes, were significantly decreased in the OVA group on P70 but not on P30. Gene set enrichment analysis of isolated microglia revealed that genes related to immune responses including Toll-like receptor signaling and chemokine signaling pathways, senescence, and glucocorticoid signaling were significantly upregulated in the OVA group compared with the control group on P30 and P70. These findings suggest that early postnatal allergic airway inflammation induces dystrophic microglia that exhibit defective synaptic pruning upon short- and long-term allergen exposure. Furthermore, long-term allergen exposure induced excitatory postsynaptic surplus and ASD-like behavior. Hypothalamo-pituitary-adrenal axis activation and the compensatory downregulation of microglial GR during long-term allergic airway inflammation may also facilitate these changes.

Neonatal reticulocyte count during the early postnatal period

BACKGROUND

There are few reports on reticulocyte count during the early postnatal period, and its clinical significance is not well understood. To examine the relationships between neonatal reticulocyte count and other perinatal variables.

METHODS

We conducted a retrospective cohort study of neonatal infants who were admitted to the neonatal intensive care unit (NICU) of Ohta Nishinouchi Hospital, Japan, between April 1, 2016 and July 31, 2019. All blood samples were collected within 3 h after admission.

RESULTS

Four hundred and twenty-eight infants were included, of whom 317 (74.1%) were preterm and 111 (25.9%) were term. Two hundred and ninety-nine infants (69.9%) were born by cesarean section. The median reticulocyte counts (‰) for all gestational ages (GAs) were as follows: 24-25 wks (n = 11), 124.1 (range: 106.3 to 148.6); 26-27 wks (n = 25), 111.1 (range: 55.5 to 144.3); 28-30 wks (n = 52), 81.9 (range: 35.6 to 131.5); 31-33 wks (n = 86), 71.6 (range: 28.3 to 116.6); 34-36 wks (n = 143); 59.6 (range: 30.2 to 110.9); and 37-41 wks (n = 111), 43.2 (range: 21.9 to 69.2). There were significant relationships between the neonatal reticulocyte count and gender [p < 0.01, odds ratio (OR), 0.37; 95% confidence interval (CI), 0.21 to 0.64], GA (p < 0.01, OR, 0.92; 95% CI, 0.90 to 0.93), delivery type (p = 0.03, OR, 0.51; 95% CI, 0.28 to 0.95), maternal haemoglobin before delivery (p < 0.01, OR, 0.74; 95% CI, 0.60 to 0.91), tracheal intubation at resuscitation (p = 0.04, OR, 2.75; 95% CI, 1.04 to 7.32) and mean platelet volume (p < 0.01, OR, 0.51; 95% CI, 0.35 to 0.74).

CONCLUSION

A higher neonatal reticulocyte count in NICU infants may be one of the physiological responses to a more rapid environmental change during the early postnatal period.

A transient insulin system dysfunction in newborn rat brain followed by neonatal intracerebroventricular administration of streptozotocin could be accompanied by a labile cognitive impairment

The early postnatal period is a critical period of hippocampus development, which is highly dependent on insulin receptor (IR) signaling and very important in cognitive function. The present study was conducted in order to present a model of neonatal transient brain insulin system dysfunction through finding an appropriate dose of injection of streptozotocin (STZ) during the neonatal period. Sixty male Wistar rat pups were divided into 4 groups of 15 and received intracerebroventricular saline or STZ (icv-STZ) (15, 20 and 25μg/kg) on postnatal day 7. Gene expression of IR and target genes for IR signaling (choline acetyltransferase (ChAT) and Tau) were measured at the ages of 2 and 7 weeks. Behavioral tests were performed at the ages of 3 and 6 weeks to assess short- and long-term cognitive function. 20μg/kg dose of icv-STZ was estimated as the optimal dose causing transient alteration in gene expression of IR, ChAT and Tau. Additionally, cognitive function of the animals restored to normal level at the age of 6 weeks. Therefore, 20μg/kg dose of icv-STZ is proposed as a new approach to generating transient brain insulin system dysfunction associated with transient cognitive impairments at a critical postnatal period of brain development.