Search

It is known that protein malnutrition conditions the development of liver steatosis, and may be accompanied by fibrosis. Ito cells intervene in the fibrogenesis, converting to transitional cells and myofibroblasts. Some trace elements, such as copper (Cu), iron (Fe) and manganese (Mn) act as co-factors, and zinc (Zn) acts as an inhibitor of a variety of enzymes involved in the collagen synthesis. This study analyzes the effects on the livers of 12 mate Wistar rats following two months administration of a hypoproteic (6%) isocaloric diet, comparing histomorphometric parameters (hepatocyte and nucleum area, total fat and fibrosis) and the liver content in Fe, Cu, Zn and Mn, with those in 12 control rats of similar age and sex. The experimental group revealed a significant reduction in hepatocyte nucleum area (p < 0.001), an increase in the ratio of hepatocyte cytoplasmatic and nucleum hepatocyte area, pronounced steatosis and slight fibrosis. No differences were found in Ito cell percentages. The experimental group showed a significant increase in liver content of Fe (p = 0.01) and a significant drop in Mn content (p < 0.01), Zn (p = 0.05) and Cu (p < 0.01). Liver iron content correlated significantly with total fat level (p = 0.03).

Lymphocytes from five severely malnourished children were cultured with bromodeoxyuridine (BrdU) and stained by the differential sister chromatid procedure using cells harvested at 48, 60, 72, 84 and 96 hours of incubation. Our results show that from 48 to 84 hours, the proportion of cells going from first to second and second to third generation cycles are higher than those cells from well-nourished children used as controls. The most dramatic difference between groups was seen at 48 hours: the proportion of first cycle metaphases was 63% and those in second cycle were 36% in the malnourished children, whereas the control group showed mainly first cycle metaphases (96%) and few (4%) had gone through the second cycle. Mathematical analysis of first cycle metaphase kinetics indicates that in the well-nourished group, 100% of the metaphases were in first cycle after 43.6 hours of culture, whereas in the malnourished group the second cycle metaphases began to appear at 36.5 hours of culture. The analysis for the third kinetics showed that the time of appearance of these cells was 8 hours earlier in the malnourished group than in the control group. These results are controversial because some authors have reported delay in the cell cycle duration. Murthy et al studying lymphocytes in vitro from children with Kwashiorkor found that the extent of this increase was 4.5 hours for the first-division cells and 1.5 hours for third division cells. However, Mutchinick et al studying nine children with severe protein malnutrition, report that the proportion of 3rd or subsequent division metaphases was higher than that seen in the control group. Our results agree with them in terms of early appearance of 3rd cycle cells.

The effect of a low protein-calorie diet (restricted diet) on cellular growth and on RNA metabolism in Wistar rat liver has been studied. Experimentation was carried out over 30 days and the comparisons were made against well-nourished group (10% protein, controls). Liver weight and hepatic proteins dropped significantly in malnourished rats. Both rate of DNA and number of nuclei were unchanged. However, protein/DNA and liver weight/number of nuclei ratios decreased, which led to an atrophy phenomenon. DNase specific activity however, was not modified. Liver RNA content together with RNase activity dropped in deficient rats. Protein synthesis capacity (RNA/protein) did not change. These results suggest that restricted diet leads to a lower hepatocyte size with a decreased rat of RNA turnover.

In adult male rats submitted during 12 weeks to a diet containing 2,5% protein the amount of hydrochloric acid and of pepsin was determined and the macro and microscopic morphology of the stomach was studied. A group fed a diet containing 20% protein was used as control. The statistical analysis of the data obtained showed that the apparent differences in the secretion of acid as well as pepsin could be attributed to the different body weights of the two groups. The morphological examination showed papillomas, frequently ulcerated occurring in the forestomach of the undernourished rats. In these areas, histological examination revealed hyperkeratosis and acanthosis. The glandular epithelium showed neither macroscopic nor microscopic alterations.