Prenatal Protein Malnutrition in Rats Alters the c-Fos Response of Neurons in the Anterior Cingulate and Medial Prefrontal Region to Behavioral Stress
Bates College, Льюистон, Maine, United States Nutritional Neuroscience
(Impact Factor: 2.27).
10/2004; 7(5-6):281-9. DOI: 10.1080/10284150400015573
Prenatal protein malnutrition affects brain development and behavior despite dietary rehabilitation from birth. Behavioral alterations include abnormal responses to stressors. To explore what brain regions mediate this altered response, we used immunocytochemistry to c-Fos protein, a transcription factor marking neuronal activation. Controls (25% casein diet) and prenatally malnourished (6% casein) adult rats were subjected to 20min of restraint stress or were unstressed. Plasma corticosterone levels were monitored before and after stress. Paired comparisons of corticosterone levels confirmed that both groups showed a significant post-stress increase. Three hours after onset of stress, rats were perfused with paraformaldehyde. Brain sections were immuno-stained together for c-Fos. Since anterior cingulate and medial prefrontal cortex modulate stress responses, labeled neurons in this region were quantified using unbiased stereology. A 2-way ANOVA of neuron numbers demonstrated a strong effect of stress and a stress by nutrition interaction. Post-hoc comparisons showed that stress significantly increased the number of c-Fos labeled neurons in both nutrition groups. Within the stress condition, prenatally malnourished rats showed a significantly greater number of c-Fos positive neurons than well-nourished rats. These results suggest that neurons in anterior cingulate and medial prefrontal regions respond excessively to restraint stress in prenatally malnourished rats.
Available from: Peter H Venables
- "In one study on humans, Kanemura, Aihara, and Nakazawa (2002) showed that malnourished children have volume reductions of the frontal and prefrontal cortex compared to control children. This is supported by work on rats, which emphasizes the effects of malnutrition on the prefrontal cortex (Rosene et al., 2004; Ruiz et al., 1986). Other animal work in contrast highlight the effect of prenatal malnutrition on the hippocampus and its connections, particularly to the amygdala (Hassanzadeh, Pour, Bayat, & Javadi, 2010; Morgane, Mokler, & Galler, 2002; Tonkiss, Galler, Morgane, Bronzino, & Austin- LaFrance, 1993). "
[Show abstract] [Hide abstract]
ABSTRACT: Previous work has shown that malnutrition has deleterious effects on both IQ and aspects of temperament. It is hypothesized that while malnutrition bears a direct relation to IQ, aspects of temperament are also involved in a mediating role so that they produce indirect associations between malnutrition and IQ. The study examines the association of 3 indices of malnutrition-stunting, anemia and wasting-to Verbal IQ (VIQ) and Performance IQ (PIQ) and temperament in 1,376 3-year-old and 11-year-old children in Mauritius. Two dimensions of temperament were extracted from ratings of behavior and were labeled as Uninhibited (UI) and Task Orientation (TO). At age 3 stunting had direct relations to Verbal IQ and Performance IQ and also indirect relations via the mediating effect of temperament (UI but not TO). In the case of anemia there were no direct relations to VIQ or PIQ but both temperament meditators were involved in indirect relations. For wasting, indirect but not direct relations were observed. When age 11 cognitive performance was examined, there were direct relations to stunting and anemia and indirect relations via UI, but not TO. The relations between malnutrition and IQ were graded and linear showing that it is not only when malnutrition is defined by its severest levels that it has an effect on cognitive performance. It is suggested that malnutrition affects those brain structures and functions that are involved in both cognitive behavior and temperament. (PsycINFO Database Record
Available from: Janina R Galler
- "One possibility is that early childhood malnutrition affects personality development via direct impacts on the brain. Early protein malnutrition impacts both the prefrontal cortex and hippocampus (Lister et al., 2011; Rosene et al., 2004). A recent PET study suggested that increased neuroticism and extraversion on the NEO-PI-R were associated with changes in glucose metabolism specific to the orbitofrontal cortex and the insular cortex (Deckersbach et al., 2006 "
[Show abstract] [Hide abstract]
Early childhood malnutrition is associated with cognitive and behavioral impairment during childhood and adolescence, but studies in adulthood are limited.
Using the NEO-PI-R personality inventory, we compared personality profiles at 37-43 years of age (M 40.3 years, SD 1.9) of Barbadian adults who had experienced moderate-to-severe protein-energy malnutrition (PEM) in the first year of life (n = 77) with healthy controls, who were former classmates of the index cases and were matched for age, gender, and handedness in childhood (n = 57). The previously malnourished participants had been rehabilitated, with good health and nutrition documented up to 12 years of age, and study participants were followed longitudinally from childhood to 40 years. Group comparisons were adjusted for childhood and adolescent standard of living, with and without correcting for IQ.
At the broad domain or factor level, previously malnourished participants had higher scores on Neuroticism and lower scores on Extraversion, Openness, Agreeableness, and Conscientiousness than did the healthy controls. At the subdomain or facet level, previously malnourished participants reported more anxiety, vulnerability, shyness and lowered sociability, less intellectual curiosity, greater suspiciousness of others, a more egocentric than altruistic orientation, and a lowered sense of efficacy or competence.
Malnutrition limited to the first year of life with good health and nutrition documented up to 12 years of age is associated with a significant overrepresentation of adult personality trait scores outside of the average range. This outcome has important implications for a variety of important life and mental health outcomes.
Available from: Hector Nuñez
- "Hypothetically, reduced glucocorticoid receptor expression in these sites would result in decreased negative feed-back control by glucocorticoids and thereby in increased HPA activity. This possibility is supported by studies reporting higher expression of hypothalamic corticotropin-releasing hormone (CRH) as well as greater plasma levels of adrenocorticotropin hormone (ACTH) and corticosterone/cortisol in rats and lambs that underwent different forms of prenatal undernutrition     . Epidemiologic studies have also associated low birth weight of babies, an index of intrauterine undernutrition , with increased basal plasma cortisol levels when adults . "
[Show abstract] [Hide abstract]
ABSTRACT: Prenatal undernutrition is known to disturb the hypothalamo-pituitary-adrenal (HPA) axis, possibly through the programming of decreased expression of hypothalamic and pituitary glucocorticoid receptors. To test this hypothesis, we examined the corticosterone response to moderate subcutaneous (100 microg/kg) and intra-paraventricular (50 pmol, bilaterally) dexamethasone (DEX) challenges in normal eutrophic and prenatally undernourished young rats. Undernutrition was induced during fetal life by restricting the diet of pregnant mothers to 10 g daily, while mothers of eutrophic rats received the same diet ad libitum. At day 40 of postnatal life (i) undernourished rats showed increased plasma corticosterone concentration compared to normals; and (ii) subcutaneous and intra-paraventricular administrations of DEX led to reduced corticosterone levels in normal and undernourished animals, the effect of DEX (administered either peripherally or centrally) being significantly lower in the latter group. Results suggest that the low sensitivity of the HPA axis to DEX as well as the increased plasma corticosterone observed in prenatally undernourished rats could be due to the already reported glucocorticoid receptor underexpression found in the hypothalamus and pituitary of in utero undernourished animals, but alternative explanations involving central noradrenergic adaptive changes could also be possible.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.