Murine maternal dietary restriction affects neural Humanin expression and cellular profile

Abstract

To understand the cellular basis for the neurodevelopmental effects of intrauterine growth restriction (IUGR), we examined the global and regional expression of various cell types within murine (Mus musculus) fetal brain. Our model employed maternal calorie restriction to 50% daily food intake from gestation day 10–19, producing IUGR offspring. Offspring had smaller head sizes with larger head:body ratios indicating a head sparing IUGR effect. IUGR fetuses at embryonic day 19 (E19) had reduced nestin (progenitors), β‐III tubulin (immature neurons), Glial fibrillary acidic protein (astrocytes), and O4 (oligodendrocytes) cell lineages via immunofluorescence quantification and a 30% reduction in cortical thickness. No difference was found in Bcl‐2 or Bax (apoptosis) between controls and IUGR, though qualitatively, immunoreactivity of doublecortin (migration) and Ki67 (proliferation) was decreased. In the interest of examining a potential therapeutic peptide, we next investigated a novel pro‐survival peptide, mouse Humanin (mHN). Ontogeny examination revealed highest mHN expression at E19, diminishing by postnatal day 15 (P15), and nearly absent in adult (3 months). Subanalysis by sex at E19 yielded higher mHN expression among males during fetal life, without significant difference between sexes postnatally. Furthermore, female IUGR mice at E19 had a greater increase in cortical mHN versus the male fetus over their respective controls. We conclude that maternal dietary restriction‐associated IUGR interferes with neural progenitors differentiating into the various cellular components populating the cerebral cortex, and reduces cerebral cortical size. mHN expression is developmental stage and sex specific, with IUGR, particularly in the females, adaptively increasing its expression toward mediating a pro‐survival approach against nutritional adversity.

Developing Brain Glucose Transporters, Serotonin, Serotonin Transporter, and Oxytocin Receptor Expression in Response to Early-Life Hypocaloric and Hypercaloric Dietary, and Air Pollutant Exposures

“…Our present investigation demonstrates that fetal brain serotonin concentrations are also reduced in the presence of maternal caloric-restricted IUGR. Both GLUT3 and serotonin expression may be reduced in the IUGR due to changes in progenitor cell proliferative processes that have previously been observed to result in microcephaly at E19 [51]. Similarly, in our present study, we observed a reduction in head weights consistent with microcephaly.…”

“…Cerebral tissues were homogenized and sonicated in RIPA buffer (20 mM Tris-HCl (pH 7.5), 150 mM NaCl, 1 mM Na 2 EDTA 1 mM EGTA 1% NP-40, 1% sodium deoxycholate, 2.5 mM sodium pyrophosphate, 1 mM β-glycerophosphate, 1 mM Na 3 VO 4 1 μg/mL leupeptin (Pierce, Waltham, WA, USA)) with protease inhibitors (Thermo Scientific, Canoga Park, CA, USA) including 2 mM PMSF, as previously subscribed [9, 51]. The resulting homogenate was centrifuged at 10,000 g at 4°C for 10 min, and the protein content was measured by the Bio-Rad protein assay (Bio-Rad Laboratories, Irvine, CA, USA) and subjected to Western blot analysis.…”

“…Genetic sex determination of E19 embryos was performed, as previously described [51]. In brief, for genetic sex determination, extracted tail DNA fragments of either the X-chromosomal Xlr gene (X-linked lymphocyte-regulated complex) or the Y-chromosomal Sly gene (Sycp3-like Y-linked) were amplified using gene-specific PCR primers [51, 57].…”

“…To this end, we have previously developed maternal dietary modified murine models. Maternal caloric restriction introduced beginning at E10 through gestation led to significant changes in neurodevelopment [51] associated with long-term emergence of anxiety [45]. On the other hand, a maternal high-fat (HF) dietary model previously reported by us led to glucose and fat metabolic changes in the mother and placenta [52].…”

Sex-dependent effects of prenatal food and protein restriction on offspring physiology in rats and mice: systematic review and meta-analyses

“…All data extracted from the 65 studies are provided in Additional file 1 . Of these studies, 29 used Wistar rats (23 performed protein restriction [ 20 – 42 ] and 6 performed food restriction [ 43 – 48 ]), 21 used Sprague-Dawley rats (7 protein restriction [ 49 – 55 ] and 14 food restriction [ 56 – 69 ]), 3 used other strains of rats (2 protein restriction with Wistar-Kyoto [ 70 , 71 ] and 1 food restriction with Long Evans [ 72 ]) and 12 used various strains of mice (7 protein restriction [ 73 – 79 ] and 5 food restriction [ 80 – 84 ]). We therefore focused primarily on studies of Wistar and Sprague-Dawley rats.…”