Moderate Physical Training Attenuates the Effects of Perinatal Undernutrition on the Morphometry of the Splenic Lymphoid Follicles in Endotoxemic Adult Rats

Abstract

Background/Aims: Physical training is a well-known inducer of positive physiological adaptations. The effects of moderate physical training on the morphometry of splenic lymphoid follicles of endotoxemic rats submitted to a perinatal low-protein (LP) diet were evaluated. Methods: Male Wistar rats were divided into two groups according to their mother’s diet (17% casein, control, C) and, undernourished (8% casein, LP diet). On postnatal day 63, the animals were submitted to moderate physical training (8 weeks, 5 days·week^–1, 60 min·day^–1, at 70% of VO_2max). After the physical training period, half of each group received an injection of either lipopolysaccharide (LPS) or saline. Plasma corticosterone concentration, blood differential leukocyte counts and splenic morphometric parameters were analyzed. Results: In undernourished toxemic (LP + LPS), LPS increased plasma corticosterone concentrations, but not in previously trained (LP + T + LPS) animals. Neutrophilia and lymphopenia in response to LPS was more pronounced in pups from undernourished mothers (LP + LPS). LP + LPS animals showed a higher increment (47.4%) in the number of lymphoid follicles, a reduction in the number and size of the splenic follicles, and in the marginal zone area. Those alterations were attenuated in trained animals (LP + T + LPS). Conclusions: Physical training attenuates the effects of nutritional programming on the splenic microanatomy by a mechanism that involves the hypothalamic-pituitary-adrenal axis.

Moderate physical training attenuates perinatal low-protein-induced spleen lymphocyte apoptosis in endotoxemic adult offspring rats

“…Moreover, protein restriction at this time may negatively affect the establishment of clonal diversity and the homeostasis of lymphocytes [11]. Consistent with previous finding, our results showed that perinatal low-protein diet is related to a reduced percentage of blood B lymphocyte, high percentage of spleen NK lymphocytes, and no changes in the percentage of differential TCD3+ lymphocytes in the peripheral blood [7,13,40]. However, to study the dynamic, morphology, and the differential count of circulating lymphocytes, it is necessary to submit Fig.…”

“…The present study showed that early low-protein diet is associated with alterations in the percentage of blood and splenic lymphocytes and loss of lymphoid cells in the spleen by enhanced apoptosis rate. Regardless of the period of the recovery, maternal low-protein diet largely affected the spleen as described in previous study [13]. However, these effects seems to be reversible, and we tested the hypothesis that moderate physical training attenuates the long-term effects of a perinatal low-protein diet on the process of immune defense by maintaining the percentage of Fig.…”

“…In our previous study [13], we demonstrated that moderate physical training attenuated the long-lasting effects of a perinatal low-protein diet on the blood lymphocyte subsets and the morphology of the spleen. Therefore, we set out to investigate the hypothesis that a defect in the underlying kinetics and distribution of lymphocytes (T, B and NK) and the high rate of apoptosis of splenic lymphocytes may explain observations of lymphopenia, low number of the splenic lymphoid follicles, and a reduced area of the marginal zone in those pups submitted to protein deprivation.…”

“…Data are presented as means + SEM. δ p < 0.05 LP + T + LPS versus LP + LPS by two-way ANOVA and Bonferroni's post hoc test ▸ the immune system to challengers, such as non-infectious stressors that activate the hypothalamus-pituitary-adrenal axis, infectious stressors, or endo-or exotoxins of pathogens [13,41]. The systemic administration of LPS induced an increase in blood B, NK, TCD4+, and TCD4+/CD8+ ratio lymphocytes and a reduction of TCD3+ and TCD8+.…”

“…In the periarteriolar area, there are around 25 % of TCD3+ lymphocytes, while 10 % of B lymphocytes are found in the germinal centers in the white pulp. The marginal zone contains B lymphocytes and phagocytes positioned along the marginal sinus, and the white pulp is composed of nodules containing lymphoid follicles (rich in B lymphocytes) [13]. During the immune response, TCD8+ lymphocytes act in association with macrophages to stimulate phagocytosis of blood-borne bacteria that is an important mechanism for protection against viral infection and parasites such as plasmodium [12].…”