Acute and sub-acute oral toxicity studies of standardized extract of Nasturtium officinale in Wistar rats.

Nasturtium officinale (watercress) is a perennial dicotyledonous plant, rich in vitamins, minerals and chemical compounds. The leaves of this plant, which contain glucosinolate, are used for its diuretic and hypoglycemic effects. The purpose of the study was to investigate the safety of the standardized extract of Nasturtium officinale (SENO) with phenylethyl glucosinolate 5.0 mg/ml-1, using acute and sub-acute oral dosage in Wistar rats. High-Performance Liquid Chromatography (HPLC) analyzed the chemical composition, from aerial parts of watercress. In the acute toxicity study, dose estimated was LD50 in the range of 2000-5000 mg/kg, signs of mortality and toxicity on female rats were observed for 14 days, after single doses of 2000 and 5000 mg/kg. In the sub-acute study, female and male rats, age 10 weeks, were supplemented at doses of 250, 500 and 1000 mg/kg for 28 days. On the 29th day, rats were fasted, anesthetized, euthanized, then their blood used for hematological and biochemical evaluation. No significant changes in general behavior were reported regarding the acute study, while the sub-acute study demonstrated no toxicity of the hematopoietic and biochemical systems. The results showed that SENO at dosage up to 5000 mg/kg in acute study was safe, and NOAEL (no-observed-adverse-effect levels) in the sub-acute, was up to 1000 mg/kg.

Rapid modulation of rat hepatocyte HMG-CoA reductase activity by cyclic AMP or cyclic GMP.

Rat hepatocytes were used to demonstrate rapid, transient effects on the modulation state (defined as the fraction of the enzyme present in the catalytically active form) of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase, E.C. 1.1.1.34). Insulin elevated, while glucagon, cAMP or cGMP lowered HMG-CoA reductase modulation state within 10 to 15 min. These changes were accompanied by a parallel change in sterol synthesis. Total HMG-CoA reductase activity was not altered. Rapid modulation of HMG-CoA reductase activity therefore constitutes a viable in vivo control mechanism. By contrast to the hormones and second messengers, mevalonolactone lowered both HMG-CoA reductase modulation state and total reductase quantity.

[Studies on combined lesions. 22. Studies on serum proteins by means of CAF-electrophoresis in mice, treated with whole body radiation and with open skin wounds]. / Untersuchungen über Kombinationsschäden 22. Mitteilung: Untersuchungen der Serumproteine mit Hilfe der CAF-Elektrophorese bei Mäusen, die durch Ganzkörperbestrahlungen in Kombination mit offenen Hautwunden belastet wurden

After combined injuries, much more pronounced changes in the protein composition of serum develop than simply after skin wounding or irradiation. A decrease was found in the prealbumin, albumin, alpha1-globulin and gamma-globulin fractions while the alpha2-globulin and beta-globulin fractions increased. If skin wounds were inflicted prior or almost simultaneously to irradiation, the serum protein changes as induced by irradiation become normalized earlier. I1 skin wounds were inflicted after irradiation they caused very pronounced alteration in the protein picture which develops in a course parallel to the increasing lethality. Only if the skin wounds were inflicted 21 days after irradiation, that they appeared to have nearly no influence in the form of augmenting protein changes. The gamma-globulin content increased considerably after the 14th day after irradiation. An additional skin wound, however, caused a depression of the gamma-globulins; but the values were still significantly higher than normal.