Relaxing effects of Valeriana officinalis extracts on isolated human non-pregnant uterine muscle.

OBJECTIVES: This study investigated the relaxing effects of Valeriana officinalis L. (Valerianaceae) on human uterine muscle. The major uses of this species in Europe are as a sedative and an anxiolytic; it is also used as a spasmolytic to treat gastrointestinal spasm. METHODS: We evaluated two valerian extracts (ethanolic and aqueous) in comparison with a natural mixture of valepotriates and nifedipine on spontaneous and agonist-induced contractions in non-pregnant human myometrium in vitro. Qualitative and quantitative chemical analysis was used to correlate the chemical composition of extracts with their spasmolytic effects. Myometrial strips were obtained from hysterectomy specimens of premenopausal women. Longitudinal muscle strips were mounted vertically in tissue baths under physiological conditions to record their isometric contraction. The responses of cumulative concentrations of valerian extracts on spontaneous contractions in the presence and absence of the beta-adrenoceptor blocker atenolol or the cyclooxygenase inhibitor indometacin, and on agonist-induced contractions, were investigated. KEY FINDINGS: Valerian extracts and valepotriates inhibited uterine contractility in a concentration-dependent manner. Pretreatment with either atenolol or indometacin did not affect the uterine responses to valerian extracts. Valerian extract reduced the maximal contractile response induced by acetylcholine, phenylephrine and histamine independent of the stimulus. CONCLUSIONS: Valerian extracts may have direct inhibitory effects on the contractility of the human uterus and this justifies the traditional use of this plant in the treatment of uterine cramping associated with dysmenorrhoea.

The isoflavones mixture from Trifolium pratense L. protects HCN 1-A neurons from oxidative stress.

Oxidative stress-induced neuronal cell death has been implicated in different neurological disorders and neurodegenerative diseases such as Alzheimer's disease and Parkinson's. Using the Alzheimer's disease-associated hydrogen peroxide (H(2)O(2)), we investigated the neuroprotective efficacy of a natural mixture of phytoestrogenic isoflavones (genistein, daidzein, biochanin A and formononetin) from Trifolium pratense L. (Red clover) against oxidative stress-induced cell death in human cortical cell line HCN 1-A maintained in culture. Neuronal viability was determined by MTT or trypan blue test and neuronal integrity by morphological analysis.The results obtained indicate that exposure of HCN 1-A cell cultures to hydrogen peroxide resulted in a concentration-dependent decrease in neuron viability. Concentration of H(2)O(2) ranging from 50 to 200 microg/ml were toxic to these cultures. A 24-hour pretreatment with 0.5, 1 and 2 microg/ml isoflavones extract significantly increased cell survival as evidenced by MTT or trypan blue test and significantly prevented the morphological disruption caused by H(2)O(2) as shown by microscopical inspection, indicating that neurons treated with isoflavones were protected from the cell death induced by H(2)O(2) exposure. These findings imply that the neuroprotective effect of isoflavones extract is partly associated with its antioxidant activity. Further, results of these investigations indicate that although isoflavones extract exert a neuroprotective effect, it do not promoted cortical neuron process outgrowth.

The phytoestrogenic isoflavones from Trifolium pratense L. (Red clover) protects human cortical neurons from glutamate toxicity.

The endogenous steroid estrogen has been shown to affect neuronal growth, differentiation and survival. Genistein, daidzein and other isoflavones have been shown to mimic the pharmacological actions of the gonadal steroid estrogen with which they have structural similarities. Several studies have looked at the effect of isoflavones in the brain. In the present study, human cortical cell line HCN 1-A maintained in culture was used to test the neuroprotective efficacy of a natural mixture of phytoestrogenic isoflavones (genistein, daidzein, biochanin A and formononetin) from Red clover against glutamate toxicity. Neuronal viability was determined by MTT or trypan blue test and neuronal membrane damage was quantitatively measured by lactate dehydrogenase (LDH). The results obtained indicate that exposure of HCN 1-A cell cultures to glutamate resulted in concentration-dependent decreases in neuron viability. Concentration of glutamate ranging from 0.01 to 5 mM was toxic to these cultures. A 24-h pretreatment with 0.5, 1 and 2 microg/ml isoflavones enriched fraction (IEF) significantly increased cell survival and significantly decreased cellular lactate dehydrogenase release from differentiated cortical neurons, indicating that neurons treated with isoflavones were protected from the cell death induced by glutamate exposure. Moreover, the pretreatment with IEF prevented the morphological disruption caused by glutamate as shown by microscopical inspection. These findings indicate that IEF has a neuroprotective effect in human cortical neurons and that this effect might be resulted from his antioxidant and estrogenic actions.

Biological and analytical characterization of two extracts from Valeriana officinalis.

The anticoronaryspastic and antibronchospastic activities of ethanolic and aqueous extracts of Valeriana officinalis L. roots were investigated in anaesthetized guinea-pigs and the results were correlated with the qualitative/quantitative chemical composition of the extracts in order to account for some of the common uses of this plant. The protective effects of orally administered ethanolic and aqueous extracts (50, 100 and 200 mg/kg) were evaluated against pitressin-induced coronary spasm and pressor response in guinea-pigs and were compared with those of nifedipine. Furthermore, the protective effects against histamine-induced and Oleaceae antigen challenge-induced bronchospasm were evaluated. Finally, the two valerian extracts were analytically characterized by qualitative and quantitative chromatographic analysis. The results showed that the two valeriana extracts possessed significant anticoronaryspastic, antihypertensive and antibronchospastic properties. These were similar to those exhibited by nifedipine and are due to the structural features of the active principles they contain. This study justifies the traditional use of this plant in the treatment of some respiratory and cardiovascular disorders.

Effects of isoflavones from red clover (Trifolium pratense) on skin changes induced by ovariectomy in rats.

Estrogens have a profound influence on skin. The relative hypoestrogenism that accompanies menopause exacerbates the deleterious effects of both intrinsic and environmental aging. Estrogens improve skin in many ways. Among these, they increase collagen content, skin thickness and improve skin moisture. There is evidence that diets with high levels of phytoestrogenic isoflavones are associated with a low incidence of menopausal symptoms and osteoporosis. Plant extracts such as red clover, which contain high levels of isoflavones, have been used to reduce menopausal symptoms and have been shown to reduce bone loss in healthy women. In this study to investigate the effects of red clover isoflavones on skin aging, the histology of the skin, skin thickness and the amount of total collagen determined by a colorimetric method, were studied in ovariectomized rats after treatment for 14 weeks with a red clover extract standardized to contain 11% isoflavones determined by HPLC. In ovariectomized rats the thickness and keratinization of the epidermis were reduced; glands were less in number and vascularity was poor; the distribution and morphology of the collagen bundles and elastic fibers were altered. Whereas the skin of the ovariectomized rats treated with red clover isoflavones (20 and 40 mg of total isoflavones daily for 14 weeks) appeared well organized with a normal epidermis with uniform thickness and regular keratinization; vascularity, collagen and elastic fibers were well developed. The amount of collagen significantly increased in the treated group in comparison with the control group. These findings suggest that red clover isoflavones are effective in reducing skin aging induced by estrogen deprivation.

Estrogenic activity of standardized extract of Angelica sinensis.

Since ancient times, extracts of plants have been used for women's health to prevent menopausal symptoms. The symptoms of menopause have been attributed to a reduction in the amount of estrogen produced by the ovaries. In this study the estrogenic activity of a commercial standardized extract of the roots of Angelica sinensis, used to relieve climacteric symptoms was evaluated using in vivo tests such as the degree of cornification of vaginal epithelium, uterotrophic assays and serum LH concentration in ovariectomized rats. Furthermore, the effects on the estrous cycle in rat were investigated. The results obtained have shown that the administration of a standardized ethanol extract in ovariectomized rats exhibited a stimulation of the uterine histoarchitecture, a significant cornification in the vaginal epithelium and a reduction of serum LH concentration showing the estrogenic nature of the extract. Furthermore, the administration of the extract in intact female rats provoked a significant modification of the vaginal smear in 67% of treated rats. The estrous cycle thus modified was characterized by a prolonged estrus stage with a temporary reduction of the regular cyclicity.