No abstract

In both protein energy malnutrition and vitamin D deficiency, defects in some immunological functions have been noted, but the effects on complement and immunoglobulin concentrations have not been evaluated. We assessed the effects of malnutrition and vitamin D deficiency on immunoglobulins and C3 in rats in early postnatal life during weaning and early adulthood using the rocket immunoelectrophoresis technique. In well-nourished rats, the serum levels of IgG increased from 88.5 ± 10.2 mg/dl in the newborn period to 883.4 ± 104.8 mg/dl at weaning (day 19). The adult levels, 1,325.9 ± 60.8 mg/dl, were attained by 35 days of age. Serum IgA was not detectable by our method until 20 days of age (1.1 ± 0.2 mg/dl) and reached adult levels (13.4 ± 3.2 mg/dl) by day 35. IgM was detectable in the serum of pups at 5 days of age (0.4 ± 0.07 mg/dl), increased to 27.5 ± 6.9 mg/dl at weaning and approached adult levels (93.7 ± 9.9 mg/dl) at day 35. C3 levels at birth were only 36% of adult levels and did not change during the suckling period. They then increased to levels comparable to those of adults at the age of 35 days. Serum immunoglobulins and C3 in malnourished rats were not significantly different from age-matched control pups. In pups born to dams fed a vitamin-D-deficient diet from 3 weeks of age, only the serum IgG and C3 levels were significantly lower than those of normal pups at day 1 (IgG level: 65.2 ± 6.1 vs. 88.5 ± 10.2 mg/dl; C3 level: 20.3 ± 6.9 vs. 36.2 ± 3.1% of an adult level; p < 0.005). Thus the increased susceptibility of malnourished young animals to infection does not appear to be related to a lowering of serum immunoglobulin and complement concentrations.

No abstract

Maternal vitamin D deficiency has been shown to lead to reduced body weights in developing rat pups. To evaluate the effects of vitamin D deficiency alone both in dams and pups during the perinatal age on the ontogeny of gastrointestinal enzymes, female weanling rats (3 weeks of age) were divided into three groups. Groups I and III were fed a control (vitamin-D-replete) diet. Group II were fed a vitamin-D-deficient diet. Six weeks afterward they were mated with normal male rats while continuing on their respective diets until sacrifice. Only rats that delivered their pups on the same day from each group were brought into the study. Litter sizes of groups I and II were adjusted to 10, while group III was adjusted to 13 such that the rate of growth paralleled that of group II. At 19 days after birth, all dams and pups were sacrificed. There were no differences in the calcium and phosphorus contents in breast milk obtained from dams of each group. The serum calcium concentration of pups from group II (vitamin-D-deficient) was lower than the other groups. Body weights of pups from groups II and III were significantly lower than those of group I. The mucosal weight, total mucosal protein, mucosal DNA, sucrase, and maltase activities from groups II and III were similar, but lower than group I. Pancreatic weight, total pancreatic protein, DNA, amylase, and lipase activities from groups II and III were also similar, but lower than group I. Vitamin D deficiency was confirmed in both dams and pups from group II. This deficiency during gestation and lactation apparently affected the development of gastrointestinal enzymes. The effect was, however, similar to that due to an increase in litter size (group III). The results suggest that vitamin D deficiency in dams probably caused lower milk volume which resulted in a partial dietary restriction to the pups, thus affecting the development of their pancreatic and mucosal enzymes. The effect of vitamin D deficiency is, therefore, secondary.