Effect of saponins of Panax notoginseng on synaptosomal 45Ca uptake.
(1/532)
AIM: To explore the calcium uptake antagonism of saponins of Panax notoginseng (PNS). METHODS: Synaptosomes were prepared from rat cerebral cortex by using differential Ficoll gradients. The effects of PNS on synaptosomal 45Ca uptake were measured in vitro or after acute treatment. RESULTS: PNS 50-800 mg.L-1 produced a concentration-rated inhibition of Ca2+ uptake [IC50 = 111 (46-176) mg.L-1]. Both initial and maximal uptake were inhibited. Similar effect was obtained after acute PNS treatment with 200 mg.kg-1 i.p. The blocking effect of PNS was reversed by calcium in media. CONCLUSION: PNS is a calcium channel blocker in neurons. (+info)
Herbal remedies: adverse effects and drug interactions.
(2/532)
A growing number of Americans are using herbal products for preventive and therapeutic purposes. The manufacturers of these products are not required to submit proof of safety and efficacy to the U.S. Food and Drug Administration before marketing. For this reason, the adverse effects and drug interactions associated with herbal remedies are largely unknown. Ginkgo biloba extract, advertised as improving cognitive functioning, has been reported to cause spontaneous bleeding, and it may interact with anticoagulants and antiplatelet agents. St. John's wort, promoted as a treatment for depression, may have monoamine oxidase-inhibiting effects or may cause increased levels of serotonin, dopamine and norepinephrine. Although St. John's wort probably does not interact with foods that contain tyramine, it should not be used with prescription antidepressants. Ephedrine-containing herbal products have been associated with adverse cardiovascular events, seizures and even death. Ginseng, widely used for its purported physical and mental effects, is generally well tolerated, but it has been implicated as a cause of decreased response to warfarin. Physicians must be alert for adverse effects and drug interactions associated with herbal remedies, and they should ask all patients about the use of these products. (+info)
American ginseng extract reduces scopolamine-induced amnesia in a spatial learning task.
(3/532)
OBJECTIVE: To determine if HT-1001, an extract of American ginseng, affects scopolamine-induced memory and performance deficits in a spatial learning task, alters brain concentrations of aminergic neurotransmitters, and alters choline uptake in synaptosome preparations. DESIGN: Animal study. ANIMALS: 48 Sprague Dawley rats. INTERVENTIONS: Long-term oral administration of a test material or control solution. Intraperitoneal administration of scopolamine (2 mg/kg) 30 minutes before testing. OUTCOME MEASURES: Performance on Morris water maze task, choline uptake, aminergic neurotransmitter analysis, in vitro monoamine oxidase analysis (of compounds). RESULTS: HT-1001 protected against scopolamine-induced amnesia and increased choline uptake in synaptosomal preparations. HT-1001 did not alter brain concentrations of norepinephrine, dopamine, 5-HT (serotonin), 3,4-dihydroxyphenylacetic acid or 5-hydroxyindoleactic acid. HT-1001 had a very weak ability to inhibit monoamine oxidase activity in vitro. CONCLUSIONS: HT-1001 demonstrates a capacity to protect against scopolamine-induced memory deficits. (+info)
Glucocorticoid receptor-induced down-regulation of MMP-9 by ginseng components, PD and PT contributes to inhibition of the invasive capacity of HT1080 human fibrosarcoma cells.
(4/532)
We examined the effects of the purified ginseng components, panaxadiol (PD) and panaxatriol (PT), on the expression of matrix metalloproteinase-9 (MMP-9) in highly metastatic HT1080 human fibrosarcoma cell line. A significant down-regulation of MMP-9 by PD and PT was detected by Northern blot analysis. However, the expression of MMP-2 was not changed by treatment with PD and PT. Quantitative gelatin based zymography confirmed a markedly reduced expression of MMP-9, but not MMP-2 in the treatment of PD and PT. To investigate whether the reduced level of MMP-9 by PD and PT affects the invasive capacity of HT1080 cells, we conducted an in vitro invasion assay with PD and PT treated cells. The results of the in vitro invasion assay revealed that PD and PT reduced tumor cell invasion through a reconstituted basement membrane in the transwell chamber. Because of the similarity of chemical structure between PD, PT and dexamethasone (Dexa), a synthetic glucocorticoid, we investigated whether the down-regulation of MMP-9 by PD and PT were mediated by the nuclear translocation of glucocorticoid receptor (GR). Increased GR in the nucleus of HT1080 human fibrosarcoma cells treated by PD and PT was detected by immunocytochemistry. Western blot and gel retardation assays confirmed the increase of GR in the nucleus after treatment with PD and PT. These results suggest that GR-induced down-regulation of MMP-9 by PD and PT contributes to reduce the invasive capacity of HT1080 cells. (+info)
Current perspectives in the pharmacological studies of store-operated Ca2+ entry blockers.
(5/532)
The store-operated Ca2+ entry (SOCE) pathway has aroused much interest recently not only because of its unusual nature as retrograde signaling, but also due to its wide occurrence and its possible role in physiological and pathophysiological situations. A number of synthetic or naturally occurring drugs recently used to block this Ca2+ entry pathway are briefly reviewed. Although important and interesting information has been obtained using these putative SOCE blockers described in this review, they indeed have sites of action other than the SOCE channels, and caution must be exercised in using them as putative tools to study SOCE. For instance, the highly variable potency of some synthetic blockers (SK&F 96365 and LOE 908) to inhibit SOCE has provided indirect evidence for the heterogeneous nature of the SOCE channels, an observation consistent with the differential Mn2+ permeability through SOCE in various cell types. The use of SK&F 96365 at relatively high concentrations has unexpectedly revealed its potential as an opener of a novel cation entry pathway. The ability of LU52396 to discriminate the SOCE channel in its closed/open states may be useful in the analysis of the kinetics of SOCE channel activation/inactivation. The possible presence of both agonistic and antagonistic saponins derived from ginseng plants for the study of SOCE deserves more rigorous experimental investigations, which may lay new ground for the development of new types of Ca2+ antagonists (and/or agonists) from the natural resources. (+info)
Anti-inflammatory effects of total saponins of Panax notoginseng.
(6/532)
AIM: To study the anti-inflammatory effects of total saponins of Panax notoginseng (PnS). METHODS: Rat air-pouch acute inflammatory model was established with s.c. carrageenan (Car, 25 mg.kg-1). The protein content in exudate was measured. Micro-acid titration assay and radioimmunoassay (RIA) were applied respectively to investigate effects of PnS on phospholipase A2 (PLA2) activity and dinoprostone (Din) content in exudate. Fura-2 fluorescence technique was used to determine the intracellular free calcium concentration in neutrophils (Neu-[Ca2+]i). RESULTS: At 12 h, PnS 60-240 mg.kg-1 i.p. reduced Neu counts, protein content [(7.7 +/- 1.3) to (4.4 +/- 1.4) g.L-1], and Din content [(1619 +/- 391) to (883 +/- 268) ng.L-1]; inhibited the PLA2 activity in exudate [(248 +/- 42) to (157 +/- 35) kU.L-1] in a dose-dependent manner. PnS 60, 120, and 240 mg.kg-1 lowered the level of Neu-[Ca2+]i with the inhibitory rate of 9.1%, 33.2%, and 39.4%, respectively. CONCLUSION: PnS has an obvious anti-inflammatory effect and its mechanisms are related to the inhibition of the Neu-[Ca2+]i level and PLA2 activity, and reduction of Din content. (+info)
Effect of aerobic exercise and ginsenosides on lipid metabolism in diet-induced hyperlipidemia mice.
(7/532)
AIM: To study the effect of aerobic exercise and its combination with Gin (ginsenosides from stems and leaves of ginseng) on lipid metabolism in diet-induced hyperlipidemia mice. METHODS: The mouse hyperlipidemia model was set up by feeding high cholesterol diet. Unloaded swimming was designed to be a manner of aerobic exercise. The effects of aerobic exercise and its combination with Gin on total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-c) in serum, malondialdehyde (MDA), and superoxide dismutase (SOD) in liver tissue were measured; the thymus and liver were weighed. RESULTS: (1) The mouse hyperlipidemia model was set up successfully: TC and MDA increased (P < 0.05) but HDL-c and SOD decreased (P < 0.05); the liver weight increased and the thymus weight reduced; fatty liver was found; (2) aerobic exercise reduced TC but increased MDA and HDL-c in cholesterol-rich diet mice; the liver weight did not reduce, and fatty liver did not clear up; and (3) when aerobic exercise combined with Gin, TC and TG decreased markedly (P < 0.01), and MDA also decreased (P < 0.05); SOD and HDL-c increased markedly (P < 0.01); the thymus weight increased and the liver weight decreased to normal level; fatty liver cleared up. CONCLUSION: Aerobic exercise could lower serum lipid to some extent but could not satisfactorily regulate lipid metabolism. When combined with Gin, aerobic exercise could better lower serum lipid, regulate lipid metabolism, promote antioxidation, and enhance immune activity. (+info)
Selected herbals and human exercise performance.
(8/532)
Herbs have been used throughout history to enhance physical performance, but scientific scrutiny with controlled clinical trials has only recently been used to study such effects. The following herbs are currently used to enhance physical performance regardless of scientific evidence of effect: Chinese, Korean, and American ginsengs; Siberian ginseng, mahuang or Chinese ephedra; ashwagandha; rhodiola; yohimbe; CORDYCEPS: fungus, shilajit or mummio; smilax; wild oats; Muira puama; suma (ecdysterone); Tribulus terrestris; saw palmetto berries; beta-sitosterol and other related sterols; and wild yams (diosgenin). Controlled studies of Asian ginsengs found improvements in exercise performance when most of the following conditions were true: use of standardized root extracts, study duration (>8 wk, daily dose >1 g dried root or equivalent, large number of subjects, and older subjects. Improvements in muscular strength, maximal oxygen uptake, work capacity, fuel homeostasis, serum lactate, heart rate, visual and auditory reaction times, alertness, and psychomotor skills have also been repeatedly documented. Siberian ginseng has shown mixed results. Mahuang, ephedrine, and related alkaloids have not benefited physical performance except when combined with caffeine. Other herbs remain virtually untested. Future research on ergogenic effects of herbs should consider identity and amount of substance or presumed active ingredients administered, dose response, duration of test period, proper experimental controls, measurement of psychological and physiologic parameters (including antioxidant actions), and measurements of performance pertinent to intended uses. (+info)