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1.
In order to investigate the pharmacological basis of ‘Yang-invigorating’ action, the effect of oral treatment with the methanolic extract of ‘Yang-invigorating’ herbs on ATP-generation capacity was examined, using heart homogenates prepared from herb-pretreated mice. Tonifying (i.e., health-promoting) herbs of other functional categories were also included for comparison. The results indicated that ‘Yang-invigorating’ Chinese tonifying herbs could invariably enhance myocardial ATP-generation capacity, with the extent of stimulation varying among the herbs. In contrast, ‘Yin-nourishing’ herbs either did not stimulate or even decreased myocardial ATP-generation capacity. While ‘Qi-invigorating’ herbs produced variable effects on myocardial ATP-generation capacity, most of the ‘blood-enriching’ herbs did not cause any significant changes. The results obtained from studies using myocardial mitochondrial fractions isolated from herb-pretreated mice suggest that ‘Yang-invigorating’ herbs might speed up ATP generation by increasing mitochondrial electron transport. The ensemble of results has provided evidence for the first time to support the pharmacological basis of ‘Yang invigoration’ in Chinese medicine.  相似文献   

2.
Oxidative stress and mitochondrial function are at the core of many degenerative conditions. However, the interaction between oxidative stress and in vivo mitochondrial function is unclear. We used both pharmacological (2 week paraquat (PQ) treatment of wild type mice) and transgenic (mice lacking Cu, Zn-superoxide dismutase (SOD1(-/-))) models to test the effect of oxidative stress on in vivo mitochondrial function in skeletal muscle. Magnetic resonance and optical spectroscopy were used to measure mitochondrial ATP and oxygen fluxes and cell energetic state. In both models of oxidative stress, coupling of oxidative phosphorylation was significantly lower (lower P/O) at rest in vivo in skeletal muscle and was dose-dependent in the PQ model. Despite this reduction in efficiency, in vivo mitochondrial phosphorylation capacity (ATPmax) was maintained in both models, and ex vivo mitochondrial respiration in permeabilized muscle fibers was unchanged following PQ treatment. In association with the reduced P/O, PQ treatment led to a dose-dependent reduction in PCr/ATP ratio and increased phosphorylation of AMPK. These results indicate that oxidative stress uncouples oxidative phosphorylation in vivo and results in energetic stress in the absence of defects in the mitochondrial electron transport chain.  相似文献   

3.
Mice injected repeatedly with concanavalin A (Con A) prior to and following challenge with P 815 mastocytoma are suppressed in their cell-mediated cytotoxicity responses. Earlier studies showed that pretreatment of the animals with silica to affect macrophage (M phi) functions reversed the Con A suppression. In the present paper we have shown that peritoneal exudate cells (PEC) induced/activated by ip injection of Con A were able to transfer suppression to normal mice. Separation of the PEC populations into adherent and nonadherent cells abrogated their capacity to transfer suppression. It was further shown that Con A is not functioning in this in vivo system to block effector activity of cytotoxic cells on target cells, and PEC induced with Con A were not directly cytotoxic to target P 815 cells. Finally, we were able to show that the cytotoxicity response of Con A-suppressed mice could be enhanced by treatment with concentrated culture supernatants of normal mouse spleen cells, rich in interleukin 2 (IL 2) activity. Attempts to detect a recently described mouse serum inhibitor of IL 2 in normal or Con A-treated mice were unsuccessful and spleen cells from Con A-treated mice lost their capacity to generate IL 2 in vitro when cultured under appropriate conditions. Taken together, these results suggest that suppression of cell-mediated immune responses in Con A-treated mice results from interruption of the normal generation of IL 2 helper effects necessary for the activation of cytotoxic effector T cells in vivo.  相似文献   

4.
S P Li  P Li  T T Dong  K W Tsim 《Phytomedicine》2001,8(3):207-212
Cordyceps, one of the well-known traditional Chinese medicines, consists of the dried fungus Cordyceps sinensis growing on the larva of the caterpillar. It is commonly used for the replenishment of body health. One of the known pharmacological effects is its anti-oxidation activity. However, there is a great variation of the quality in different sources of Cordyceps. Here, the water extracts of various sources of natural C. sinensis and cultured Cordyceps mycelia were analyzed for their anti-oxidation activity by using three different assay methods such as the xanthine oxidase assay, the induction of hemolysis assay and the lipid peroxidation assay. The results showed that Cordyceps, in general, possesses a strong anti-oxidation activity in all assays tested. However, both natural and cultured Cordyceps showed the lowest inhibition in the lipid peroxidation when compared with the other two assay methods. The cultured Cordyceps mycelia had equally strong anti-oxidation activity as compared to the natural Cordyceps. Besides, the anti-oxidation activities were increased to 10-30 folds in the partially purified polysaccharide fractions from the cultured Cordyceps mycelia, which suggested that the activity could be derived partly from Cordyceps polysaccharides.  相似文献   

5.
Thyroid acting through ligand binding to nuclear receptors modifies myocardial respiratory kinetics and oxidative phosphorylation in the heart. Direct nongenomic action of thyroid hormone on high-energy phosphate concentrations and respiratory kinetics has never been proven in vivo but might be responsible for observed changes in oxygen utilization efficiency immediately after triiodothyronine (T3) administration. We tested the hypothesis that T3 directly and rapidly modifies myocardial high-energy phosphate concentrations and phosphorylation potential in vivo. Anesthetized sheep (age 28-40 days) thyroidectomized shortly after birth (Thy) and euthyroid age-matched controls (Con) underwent median sternotomy and received T3 infusion (0.8 microg/kg), followed by epinephrine infusion to increase myocardial oxygen consumption (MVo2). 31P magnetic resonance spectra were monitored via a surface coil over the left ventricle. T3 increased phosphocreatine (PCr)/ATP and decreased ADP in Thy animals without causing a change in MVo2. T3 produced no changes in high-energy phosphates in Con animals. T3 did not modify the PCr/ATP or ADP response to epinephrine and elevation in MVo2 in either group. Cardiac mitochondria isolated from Thy and Con animals showed no change in respiratory rate or ADP/ATP exchange efficiency after T3 incubation. T3 infusion in a hypothyroid state decreases ADP concentration, thereby altering the equilibrium between phosphorylation potential and myocardial respiratory rate. These T3-induced effects are not due to changes in ADP/ATP exchange efficiency through action at the adenine nucleotide translocator but may be due to T3 mediation of substrate utilization, confirmed in other models.  相似文献   

6.
Zhang Y  Zhu H  Ye G  Huang C  Yang Y  Chen R  Yu Y  Cui X 《Life sciences》2006,78(17):1998-2005
Coxsackievirus B3 (CVB3) is a major pathogen for acute and chronic viral myocarditis. The aim of this study was to investigate the antiviral effects of sophoridine, an alkaloid extracted from Chinese medicinal herb, Sophora flavescens, against CVB3, and the underlying pharmacokinetics. First, we determined the antiviral effects of sophoridine against CVB3 in in vitro (primarily cultured myocardial cells), in vivo (BALB/c mice) and serum pharmacological experiments. Then, we determined the pharmacokinetic behavior in serum samples of SD rats after oral administration by HPLC. Finally, we determined the effects of sophoridine on the production of cytokines in a murine viral myocarditis model by measuring mRNA expression of some important cytokines in hearts of infected BALB/c mice by RT-PCR. We found that sophoridine exhibited obvious antiviral effects both in vitro and in vivo, and serum samples obtained from rats with oral administration of sophoridine reduced the virus titers in infected myocardial cells. The serum concentration profile correlated closely with antiviral activity profile. Moreover, sophoridine significantly enhanced mRNA expression of IL-10 and IFN-gamma, but decreased TNF-alpha mRNA expression. In conclusion, sophoridine possesses antiviral activities against CVB3, by regulating cytokine expression, and it is likely that sophoridine itself, not its metabolites, is mainly responsible for the antiviral activities. Therefore, sophoridine may represent a potential therapeutic agent for viral myocarditis.  相似文献   

7.
Cordyceps (summer-grass, winter-worm), one of the most valued traditional Chinese medicines, is used commonly for the replenishment of body health. It consists of the dried fungus Cordyceps sinensis growing on caterpillar larvae. For medication, the fruiting body (fungus) and the worm (caterpillar) are used together. However, the pharmacological efficiency and the main constituents of the individual parts have not been determined. In the present study the water extracts from the fruiting body and worm of natural Cordyceps were analyzed for their content of nucleosides and polysaccharides; the results showed that the worm had chemical composition similar to the fruiting body. In addition, both the fruiting body and worm of Cordyceps showed similar potency in their anti-oxidation activities in the xanthine oxidase assay, the induction of hemolysis assay and the lipid-peroxidation assay. These results suggest that the function of the worm in Cordyceps is to provide a growth medium for the fruiting body, and that eventually, the worm is totally invaded by C. sinensis mycelia.  相似文献   

8.
When normal mouse spleen cells are cultured in vitro, large numbers of cells develop that produce antibody toward antigens found on bromelain-treated mouse erythrocytes (BrMRBC). The in vitro culture also generates T cells that mediate DTH toward these antigens. We have suggested that under in vivo conditions, suppressor T cells maintain these immune responses at a low level but that this suppression wanes when the cells are cultured in vitro. The present study examines the effect of concanavalin A (Con A) on the in vitro development of humoral and cell-mediated immunity to Br-MRBC. Mitogenic concentrations of Con A prevented the development of both the PFC and TDTH responses toward BrMRBC. The Con A-induced suppression was due to the induction of suppressor T cells; thus the addition of Con A-activated cells to fresh spleen cell cultures prevented the development of both the PFC and TDTH response against BrMRBC.  相似文献   

9.
A quantitative in vitro technique was used to compare the ability of different endotoxins to inhibit the migration of macrophages from explants of rabbit spleen cultured in a coagulated plasma medium. The order of potency was different from that observed in chick embryo assays, and in assays with mice, of the same endotoxins. In general, however, the sensitivity of the macrophage inhibition test was comparable to that of other bioassay methods. A highly purified endotoxin from Salmonella enteritidis (Ribi) in a concentration of 0.004 mug/ml regularly inhibited macrophage migration. The in vitro method was used to detect a progressive loss of biological activity in fractions obtained during acid hydrolysis of the purified endotoxin. The selective toxicity of very low concentrations of endotoxin for mammalian macrophages was important in estimating the degree of specificity of the reaction. The pattern of cellular response in explant cultures made it possible to differentiate endotoxic damage from the specific cytotoxic action of antigen associated with delayed hypersensitivity.  相似文献   

10.
We have analyzed gastrointestinal immune function in both DBA/2 and spontaneously autoimmune New Zealand Black (NZB) mice. We have studied both in vitro proliferation and differentiation of Peyer's patch cells and have measured immunoglobulin (Ig) secretion by cultured jejunal segments. Peyer's patch B cells and T cells from both DBA/2 and NZB mice showed similar proliferative responses to Con A and lipopolysaccharide (LPS), respectively. Unlike NZB splenic B cells, isolated Peyer's patch B cells from NZB mice did not spontaneously secrete Ig of any isotype. Seven-day cultures of equal numbers of Peyer's patch T cells and B cells resulted in similar patterns of secretion of IgA, IgG, and IgM in both strains. The addition of Con A to cultures of DBA/2 Peyer's patch cells consistently resulted in a onefold to threefold increase in IgA secretion after 7 days. Con A stimulation of NZB Peyer's patch cells did not produce any increment in IgA secretion. LPS stimulation of Peyer's patch cells from either strain resulted in a similar increase in IgG secretion with little effect on IgA secretion. The in vivo correlate of this finding was seen in the IgA to IgG ratio of Ig secreted by cultured jejunal fragments. In DBA/2 mice the rates of IgA/IgG varied from 2.36 to 4.85, whereas in NZB mice the ratio never exceeded 0.5. These experiments show that defects on the T cell compartment of NZB mice encompass gut-associated lymphoid tissue. The possible relationship of these findings and previously observed defects in oral tolerance is discussed.  相似文献   

11.
Brief periods of ischemia and reperfusion that precede sustained ischemia lead to a reduction in myocardial infarct size. This phenomenon, known as ischemic preconditioning, is mediated by signaling pathway(s) that is complex and yet to be fully defined. AMP-activated kinase (AMPK) is activated in cells under conditions associated with ATP depletion and increased AMP/ATP ratio. In the present study, we have taken advantage of a cardiac phenotype overexpressing a dominant negative form of the alpha2 subunit of AMPK to analyze the role, if any, that AMPK plays in preconditioning the heart. We have found that myocardial preconditioning activates AMPK in wild type, but not transgenic mice. Cardiac cells from transgenic mice could not be preconditioned, as opposed to cells from the wild type. The cytoprotective effect of AMPK was not related to the effect that preconditioning has on mitochondrial membrane potential as revealed by JC-1, a mitochondrial membrane potential-sensitive dye, and laser confocal microscopy. In contrast, experiments with di-8-ANEPPS, a sarcolemmal-potential sensitive dye, has demonstrated that intact AMPK activity is required for preconditioning-induced shortening of the action membrane potential. The preconditioning-induced activation of sarcolemmal K(ATP) channels was observed in wild type, but not in transgenic mice. HMR 1098, a selective inhibitor of sarcolemmal K(ATP) channels opening, inhibited preconditioning-induced shortening of action membrane potential as well as cardioprotection afforded by AMPK. Immunoprecipitation followed by Western blotting has shown that AMPK is essential for preconditioning-induced recruitment of sarcolemmal K(ATP) channels. Based on the obtained results, we conclude that AMPK mediates preconditioning in cardiac cells by regulating the activity and recruitment of sarcolemmal K(ATP) channels without being a part of signaling pathway that regulates mitochondrial membrane potential.  相似文献   

12.
To verify whether the sleep-inducing properties of oleamide were related to its ability to perturb membrane homeoviscosity, affecting 5-HT(2A) receptors, we compared the effects of oleamide and oleic acid, the latter lacking both the sleep-inducing effect and the action on 5-HT(2A) receptors. In binding studies the two compounds did not directly interact with rat brain cortex 5-HT(2A) receptors, nor did they increase the affinity of a 5-HT(2A) agonist, either in vitro or ex vivo. They had similar fluidizing effects, in vitro at high concentrations (>/=10 microM), and ex vivo after a dose of 100 mg/kg, and they reduced locomotor activity with similar potency. There thus appears to be no causal relationship between the fluidizing effects of oleamide and its sleep-inducing properties.  相似文献   

13.
组织培养暗紫贝母的药理作用   总被引:6,自引:0,他引:6  
以组织培养的暗紫贝母为材料,野生暗紫贝母为对照,用不同溶剂提取,得4个化学组人 生物碱部分,总皂甙部分,水溶性部分和脂溶性部分,并以生药粉为阳性对照进行药效学试验。结果表明:组培贝母与野生贝母有相似的止咳、祛痰作用;总皂甙部分与总生物碱部分均为川贝有效活性成分,t得之间无显著性差异;经TLC是乌头总生物碱部分与总皂甙部分无化学成分重叠。  相似文献   

14.
Estrogenic action of estriol fatty acid esters   总被引:1,自引:0,他引:1  
Recent studies suggest that, estriol, like estradiol, is biosynthetically esterified with fatty acids. We have synthesized the stearate estriol, at C-16 alpha, C-17 beta and the diester, C-16 alpha,17 beta and tested these D-ring esters for their estrogenic action both in vivo and in vitro, comparing them to estradiol, estriol and estradiol-17-stearate. None of the estriol esters bind to the estrogen receptor. They are only weakly estrogenic in a microtiter plate estrogen bioassay: stimulation of alkaline phosphatase in the Ishikawa endometrial cells. However, both estriol monoesters are extremely potent estrogens when injected subcutaneously (in aqueous alcohol) into ovariectomized mice. Compared to the free steroids, they produced a dramatically increased uterine weight with a greatly prolonged duration of stimulation. The 16 alpha,17 beta-diester also induced a protracted uterotrophic response, but the stimulation of uterine weight was comparatively low. Since the esters of estradiol and estriol do not bind to the estrogen receptor, their estrogenic signal must be generated through the action of esterase enzymes. These naturally occurring esters have the potential of being extremely useful pharmacological agents for long-lived estrogenic stimulation.  相似文献   

15.
Splenic lymphocytes from mice treated with Propionibacterium acnes cells as well as with their cell walls were found to be variably active on the lymphoproliferative responsiveness. Furthermore, the effect of these bacterial agents on the ex vivo Con A response of the lymphocytes showed a certain stimulation that was higher with oral treatments. In the same conditions the influence of these agents on the LPS lymphocytes stimulation was almost without any statistical significance. In vitro blastogenesis experiments were undertaken in order to elucidate the influence of different amphiphilic molecules from peripheric bacterial structures on the lymphoproliferative response of murine splenocytes. Stimulation rates were also determined as a function of the (3H) thymidine incorporation. Combined effects of mitogens (Con A and LPS) with bacterial amphiphilic molecules were also evaluated as a function of the DNA synthesis variations. All cases resulted in a variable inhibition of the mitogenic response which appeared dose-dependent and more active for associations of Con A and amphiphilic molecules. The most effective intrinsic mitogenic activities were detected with teichoic acids and intracellular polysaccharides. These last molecules without purification, assayed as cytoplasmic fractions, appeared modified in the intensity of their action, depending on their carbohydrate/protein ratios.  相似文献   

16.
Accumulating evidence indicates an important role for serine phosphorylation of IRS-1 in the regulation of insulin action. Recent studies suggest that Rho-kinase (ROK) is a mediator of insulin signaling, via interaction with IRS-1. Here we show that insulin stimulation of glucose transport is impaired when ROK is chemically or biologically inhibited in cultured adipocytes and myotubes and in isolated soleus muscle ex vivo. Inactivation of ROK also reduces insulin-stimulated IRS-1 tyrosine phosphorylation and PI3K activity. Moreover, inhibition of ROK activity in mice causes insulin resistance by reducing insulin-stimulated glucose uptake in skeletal muscle in vivo. Mass spectrometry analysis identifies IRS-1 Ser632/635 as substrates of ROK in vitro, and mutation of these sites inhibits insulin signaling. These results strongly suggest that ROK regulates insulin-stimulated glucose transport in vitro and in vivo. Thus, ROK is an important regulator of insulin signaling and glucose metabolism.  相似文献   

17.
Selective impairment of B cell function by Neisseria meningitidis   总被引:1,自引:0,他引:1  
Spleen cells from CBA/J mice infected with Neisseria meningitidis displayed depressed in vitro plaque-forming cell (PFC) responses to T-dependent (sheep red blood cell; SRBC) and T-independent (TNP-LPS, TNP-Ficoll) antigens. The inhibition was observed over a wide range of antigen concentrations. The decreased responsiveness of splenocytes from infected mice was due to a selective impairment of B-cell function since helper-T-cell activity was intact in infected mice as shown by the ability of T-enriched lymphocytes to cooperate with normal B-enriched lymphocytes in the generation of an anti-SRBC response, accessory macrophage function was preserved since adherent spleen cells from bacteria-injected mice were shown to produce normal or increased levels of IL-1 and were able to cooperate with normal non-adherent spleen cells in the generation of PFC against SRBC. Addition of peritoneal cells from normal animals or extraneous IL-1 both failed to restore normal PFC responses in cultures of splenocytes from infected mice. Finally, B-enriched lymphocytes from infected mice produced poor anti-SRBC responses when cultured with either Con A supernatant or T-enriched lymphocytes from normal or infected mice. Cell-mixing experiments failed to detect the presence of suppressor cells in cultures of unfractionated spleen cells or B-enriched lymphocytes from infected mice. Therefore, the immunological unresponsiveness associated with a Neisseria meningitidis infection was attributed to a meningococcus-induced defect(s) in B-cell function. In vivo polyclonal B-cell activation leading to clonal exhaustion did not play a major role in the depression of humoral responses since meningococcal infection induced little or no polyclonal Ig secretion.  相似文献   

18.
Lymphocyte responses to the galactosyl binding lectins, SBA and PNA, and responses to Con A are suppressed by cAMP analogs and agents that increase intracellular cAMP to a greater extent than are responses to PHA. Adenosine shares with cAMP this selective inhibitory effect. ATP inhibits lymphocyte proliferation via generation of adenosine. This conclusion is based on the findings that (i) β,γ-methylene ATP (β,γ-met ATP) is similar to ATP in its inhibitory effects, whereas α,β-met ATP has little effect on lymphocyte proliferation, (ii) α,β-met ATP reverses both ATP and β,γ-met ATP induced suppression, but does not reverse adenosine-mediated suppression, and (iii) inhibition of adenosine deaminase potentiates ATP and β,γ met ATP-mediated suppression of blastogenesis. The relative potency of various noncyclic adenosine compounds in suppressing mitogen-induced blastogenesis is: 2-chloradenosine > ATP ≥ ADP > AMP > adenosine.  相似文献   

19.
The systemic inflammatory response syndrome is a complex host response to a variety of clinical insults, generally leading to severe pathology. The human chorionic gonadotropin β-chain-related tetrapeptide leucine-glutamine-glycine-valine (LQGV) reduces hemorrhagic and LPS-induced systemic inflammatory response syndrome, but its mechanisms of action are not yet fully understood. Through the combination of in vivo, in vitro, and ex vivo approaches, we demonstrate that LQGV actively stimulates corticosterone production in mice and thereby suppresses in vivo TLR4-directed inflammation upon LPS administration. Blocking in vivo glucocorticosteroid receptor signaling reduced the prosurvival effect of LQGV. Also, upon multiple TLR activation by heat-killed Listeria monocytogenes, splenocytes from LQGV-treated mice produced significantly less TNF-α and IL-6, which was absent after in vitro blockage of the glucocorticosteroid receptor. Using adrenal gland and adrenal cell line cultures, we show that LQGV stimulates corticosterone production. Moreover, by using specific pharmacological inhibitors of the adrenocorticotropic hormone (ACTH) and luteinizing hormone receptors as well as of cAMP signaling, we demonstrate that LQGV stimulates the ACTH receptor. These data show that the β-human chorionic gonadotropin-related tetrapeptide LQGV stimulates adrenal glucocorticosteroid production through activation of the ACTH receptor with consequent glucocorticoid receptor activation and immunosuppression in C57BL/6 mice.  相似文献   

20.
为研究TGF β1 SMAD3信号对小鼠软骨细胞增殖和分化的影响 ,分离了野生型与Smad3基因剔除 (Smad3ex8 ex8)突变纯合子小鼠肋骨软骨细胞并进行了体外培养 .通过3 H TdR参入实验检测了体外培养软骨细胞的增殖能力 .TGF β1可以刺激野生型软骨细胞的增殖 ,Smad3基因缺失导致小鼠软骨细胞丧失对TGF β1刺激生长作用的应答 .Northern杂交显示 ,TGF β1促进野生型小鼠软骨细胞表达Ⅱ型胶原 ,而Smad3基因缺失突变纯合子软骨细胞大量表达肥大性软骨细胞的分子标记物X型胶原 .结果表明 ,SMAD3介导转化生长因子TGF β1刺激软骨细胞增殖并抑制软骨细胞的肥大性分化  相似文献   

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