Alpha-mannosidase activity in goats fed with Sida carpinifolia.

Human alpha-mannosidosis results from alpha-mannosidase deficiency and progressive accumulation of mannose-rich oligosaccharides in lysosomes. Two days before Saanen goats were fed with Sida carpinifolia, alpha-mannosidase activity in leukocytes was 128+/-28 nmoles4-MU/h/mgprotein (first trial) and 104+/-6 nmoles4-MU/h/mgprotein (second trial). At day 5, after the introduction of S. carpinifolia diet, the alpha-mannosidase activity in leukocytes was significantly increased, both in the first (288+/-13 nmoles4-MU/h/mgprotein) and in the second trial (303+/-45 nmoles4-MU/h/mgprotein), and it returned to normal levels 2 days after the withdrawal of the plant from the diet (114+/-7 nmoles4-MU/h/mgprotein in first trial, and 108+/-25 nmoles4-MU/h/mgprotein in the second one). Plasma alpha-mannosidase activity decreased significantly 4 days after animal exposure to the S. carpinifolia diet (769+/-167 nmoles4-MU/h/ml) and returned to normal values 10 days after the withdrawal of the plant from the diet (1289+/-163 nmoles4-MU/h/ml). Thin-layer chromatography showed an abnormal excretion of oligosaccharides in urine as of day 2 after diet exposure, which persisted until one day after the withdrawal of the plant. Animals presented neurological clinical signs beginning at day 37 (in the first trial) and at day 25 (in the second trial) after being fed with the plant. The results obtained herein suggest that oligosaccharides observed in urine are a result of a decrease in alpha-mannosidase activity in plasma. S. carpinifolia seems to have other compounds that act on alpha-mannosidase enzyme in leukocytes in a competitive manner with swainsonine. The increase in alpha-mannosidase enzyme in leukocytes could be attributed to one of these compounds present in S. carpinifolia.

Urinary oligosaccharides: a peripheral marker for Sida carpinifolia exposure or poisoning.

Poisoning by Sida carpinifolia belongs to a group of plant-induced phenotype which resembles lysosomal storage diseases. Saanen goats were fed aerial parts of green S. carpinifolia for up to 3 months. Concentrates complemented the nutritional requirements. Urine and blood samples were collected for oligosaccharide study (by thin layer chromatography-TLC) and hemogram analysis, respectively. Abnormal excretion of oligosaccharides was observed from the 2nd day of S. carpinifolia ingestion until one day after withdrawal of the plant from the diet. There were no changes in hemogram. Clinical signs were typical of poisoning caused by plants of this group and were seen from the 37th day on S. carpinifolia diet until seven days after withdrawal of the plant, when signs gradually became scarce and less evident. Results presented here suggest that detection of urinary oligosaccharides by TLC may be an useful method to assess swainsonine-containing plants exposure or an early diagnostic tool for poisoning by these plants.