Untersuchungen über die kalzinogene Aktivität von siliertem Goldhafer (Trisetum flavescens [L.] [P. B.])

Enzootic calcinosis in ruminants: A review

Enzootic calcinosis (EC), is a chronic disease, caused by toxic plants, which has mainly affected ruminants for more than 100 years. It is characterized by a soft tissue calcification, hypercalcemia, hyperphosphatemia, hypoparathiroidism, hypercalcitoninism, osteonecrosis, and osteopetrosis. The toxic compound reported in some of these plants are 1,25(OH)₂D₃ glycosides. Characterization of calcinogenic principles were performed with Solanum glaucophyllum, Trisetum flavescens, Cestrum diurnum, and Stenotaphrum secundatum. Other plant species involved in EC are: Nierembergia rivularis, Nierembergia veitchii, Solanum torvum, and Solanum stuckertii. Clinical and pathological findings are well characterized. We present different aspects of the pathogenic mechanism of EC, including genetic modulation, expression of bone proteins, cellular de-differentiation of arterial smooth muscle cells, phenotypic changes, production of a calcifiable matrix, and modulation of the calcium and phosphorus balance. The use of comparative pathology can bring significant advances in the understanding of the pathogenic mechanism. In this review we present a broad approach to the different aspects of intoxication: history of EC on different continents; plant species, distribution and morphology; toxic principle; pathogenesis; epidemiology; clinical signs; diagnosis; and control and prophylaxis.

Evidence for aqueous soluble vitamin D-like substances in the calcinogenic plant, Tristetum flavescens

A crude aqueous extract of the leaves of T. flavescens when administered orally to vitamin D-deficient chicks produced significant increases in plasma phosphate but had little effect on plasma calcium. When chicks, fed a high strontium diet to inhibit endogenous 1,25 (OH)2 vitamin D3 production and intestinal calcium transport, were dosed with the extract or synthetic 1,25 (OH)2D345Ca absorption from the duodenum in vivo was stimulated, whereas vitamin D3 was ineffective. Partial purification of the crude extract on a Sephadex GH25 column yielded two factors, one of which mimicked 1,25 (OH)2D3 activity in chicks fed the high strontium diet while the other produced a significant increase in plasma phosphate. The presence of these substances, together with previously demonstrated organic solvent soluble vitamin D-type activity, may account for the calcinogenic nature of the plant.