曲格列酮对大鼠肝细胞氧化性损伤的研究

目的:研究曲格列酮的肝细胞毒性及其可能的机制.方法:在原代大鼠肝细胞模型和其他3种不同来源非肝细胞系,用WST-1法、乳酸脱氢酶释放法、荧光检测法、生物发光法等方法,观察曲格列酮对肝细胞的损伤作用.结果:不同剂量曲格列酮作用后,其在原代培养大鼠肝细胞的IC50值最低,即其对原代肝细胞毒性最大.曲格列酮诱导活性氧(ROS)生成,并引起还原型谷胱甘肽(GSH)和ATP水平比对照细胞显著降低.不同剂量的曲格列酮作用5h后诱发肝细胞凋亡、坏死.结论:曲格列酮对大鼠肝细胞的毒性作用强于对其他非肝细胞来源细胞的毒性作用.曲格列酮可以引起肝细胞氧化性损伤,肝细胞凋亡和坏死.     

Neuroprotection of Ilex latifolia and caffeoylquinic acid derivatives against excitotoxic and hypoxic damage of cultured rat cortical neurons

Ilex latifolia (Aquifoliaceae), one of the primary components of "Ku-ding-cha", has been used in Chinese folk medicine to treat headaches and various inflammatory diseases. A previous study demonstrated that the ethanol extract of I. latifolia could protect against ischemic apoptotic brain damage in rats. The present study investigated the protective activity of I. latifolia against glutamate-induced neurotoxicity using cultured rat cortical neurons in order to explain a possible mechanism related to its inhibitory effect on ischemic brain damage and identified potentially active compounds from it. Exposure of cultured cortical neurons to 500 μM glutamate for 12 h triggered neuronal cell death. I. latifolia (10-100 μg/mL) inhibited glutamate-induced neuronal death, elevation of intracellular calcium ([Ca(2+)](i)), generation of reactive oxygen species (ROS), the increase of a pro-apoptotic protein, BAX, and the decrease of an anti-apoptotic protein, BcL-2. Hypoxia-induced neuronal cell death was also inhibited by I. latifolia. 3,4-Dicaffeoylquinic acid (diCQA), 3,5-diCQA, and 3,5-diCQA methyl ester isolated from I. latifolia also inhibited the glutamate-induced increase in [Ca(2+)](i), generation of ROS, the change of apoptosis-related proteins, and neuronal cell death; and hypoxia-induced neuronal cell death. These results suggest that I. latifolia and its active compounds prevented glutamate-induced neuronal cell damage by inhibiting increase of [Ca(2+)](i), generation of ROS, and resultantly apoptotic pathway. In addition, the neuroprotective effects of I. latifolia on ischemia-induced brain damage might be associated with the anti-excitatory and anti-oxidative actions and could be attributable to these active compounds, CQAs.     

Protective effects of fangchinoline and tetrandrine on hydrogen peroxide-induced oxidative neuronal cell damage in cultured rat cerebellar granule cells

The present study was performed to examine the neuroprotective effects of fangchinoline (FAN) and tetrandrine (TET), bis-benzylisoquinoline alkaloids, which exhibit the characteristics of Ca 2+ channel blockers, on H2O2 -induced neurotoxicity using cultured rat cerebellar granule neurons. H2O2 produced a concentration-dependent reduction of cell viability, which was blocked by (5 R,10 S)-(+)-5-methyl-10,11-dihydro-5 H-dibenzo[ a,d]cyclohepten-5,10-imine (MK-801), an N-methyl- D-aspartate (NMDA) receptor antagonist, verapamil, an L-type Ca 2+ channel blocker, and NG-nitro- L-arginine methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor. Pretreatment with FAN and TET over a concentration range of 0.1 to 10 microM significantly decreased the H2O2 -induced neuronal cell death as assessed by a trypan blue exclusion test, a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and the number of apoptotic nuclei. In addition, FAN and TET inhibited the H2O2 -induced elevation of glutamate release into the medium, elevation of the cytosolic free Ca 2+ concentration ([Ca 2+] c ), and generation of reactive oxygen species (ROS). These results suggest that FAN and TET may mitigate the harmful effects of H2O2 -induced neuronal cell death by interfering with the increase of [Ca 2+] c, and then by inhibiting glutamate release and generation of ROS. Abbreviations. AP5:D(-)-2-amino-5-phosphonopentanoic acid DMSO:dimethyl sulfoxide FAN:fangchinoline H 2 DCF-DA:2',7'-dichlorodihydrofluorescin diacetate MK-801:(5 R,10 S)-(+)-5-methyl-10,11-dihydro-5 H-dibenzo[ a,d]cyclohepten-5,20-imine MTT:3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide L-NAME: NG-Nitro- L-arginine methyl ester NMDA: N-methyl- D-aspartate TET:tetrandrine     

木犀草素对大鼠皮层神经元氧化损伤的保护作用

目的研究木犀草素对于皮层神经元氧化损伤的保护作用及其机制。方法用200μmol·L-1H2O2处理皮层神经元造成神经元的氧化损伤,用LDH活性检测细胞死亡,MTT测定线粒体活性,荧光分光检测神经元线粒体膜电位,细胞内ROS的积累以及过氧化氢酶和谷胱甘肽的含量变化。结果20μmol·L-1的木犀草素能有效的保护H2O2导致的神经元死亡,有效维护线粒体膜电位和线粒体活性,减少细胞内ROS的累积,并能通过提高细胞内谷胱甘肽的含量有效对抗氧化损伤,同时对于H2O2造成的过氧化氢酶活力和谷胱甘肽含量的急剧下降也有很好的保护作用。结论木犀草素是一种比较有效的对抗神经元氧化损伤的保护剂,它很可能通过维持线粒体的活性而达到神经保护作用,并通过提高细胞内谷胱甘肽的水平,增强神经元抗氧化损伤的能力。     

MANF对神经细胞中tau蛋白过度磷酸化的抑制作用

目的观察MANF是否可以抑制冈田酸诱导的N2a细胞中tau蛋白的过度磷酸化,以了解MANF神经保护作用的机制。方法采用体外培养小鼠神经母瘤细胞株N2a,以冈田酸(okadaic aicd,OA)作为诱导剂诱导N2a细胞中tau蛋白过度磷酸化,在加入重组人MANF蛋白干预或转染MANF过表达质粒及siRNA后,用MTT法检测细胞增殖活性的变化,并用AT-8抗体检测tau蛋白ser202/Thr205位点的磷酸化水平变化。结果 N2a细胞在加入重组人MANF蛋白预处理4 h后加入OA诱导24 h后,经Western blot和MTT法检测发现,重组人MANF蛋白能明显抑制N2a细胞中tau蛋白的过度磷酸化,并可促进N2a细胞的增殖活性;在转染MANF过表达质粒后,N2a细胞中OA诱导的过度磷酸化tau蛋白减少,且细胞活性增加;与此相反,转染siRNA下调内源性的MANF的表达则能促进N2a细胞中的tau蛋白过度磷酸化,并抑制细胞活性。结论 MANF可以抑制神经细胞中tau蛋白过度磷酸化,这可能是其发挥神经保护作用的原因之一。     

Decursinol and decursin protect primary cultured rat cortical cells from glutamate-induced neurotoxicity

We previously reported six neuroprotective decursinol derivatives, coumarins from Angelica gigas (Umbelliferae) roots. To elucidate the action patterns of decursinol derivatives, we investigated the neuroprotective effects of decursinol and decursin, which showed highly significant activity and were major constituents of A. gigas, using primary cultures of rat cortical cells in-vitro. At concentrations of 0.1-10.0 microM, both decursinol and decursin exerted a significant neuroprotective activity pretreatment and throughout treatment. In addition, decursin had a neuroprotective impact in the post-treatment paradigm implying that decursin might possess different action mechanisms from that of decursinol in the protection of neurons against glutamate injury. Both decursinol and decursin effectively reduced the glutamate-induced increased intracellular calcium ([Ca(2+)](i)) in cortical cells, suggesting that these two coumarins may exert neuroprotection by reducing calcium influx by overactivation of glutamate receptors. This suggestion was supported by the result that decursinol and decursin protected neurons against kainic acid (KA)-induced neurotoxicity better than against that induced by N-methyl-D-aspartate (NMDA). Moreover, both decursinol and decursin significantly prevented glutamate-induced decreases in glutathione, a cellular antioxidant, and glutathione peroxidase activity. In addition, both compounds efficiently reduced the overproduction of cellular peroxide in glutamate-injured cortical cells. These results suggested that both decursinol and decursin protected primary cultured rat cortical cells against glutamate-induced oxidative stress by both reducing calcium influx and acting on the cellular antioxidative defence system. Moreover, decursin is considered to probably have a different action mechanism from that of decursinol in protecting cortical cells against glutamate injury.     

羟丁酸钠对大鼠原代培养皮层神经元缺氧复氧损伤的保护作用与GABAA受体的关系

目的 :探讨羟丁酸钠 (SO)对大鼠皮层神经元缺氧复氧损伤的保护作用与GABAA 受体的关系。方法 :采用原代培养大鼠皮层神经元建立缺氧复氧损伤模型 ,观察细胞的形态学 ,测定其LDH漏出率、MDA含量、SOD、GPx活力。结果 :缺氧复氧可引起神经元损伤 ,LDH漏出率增加 ,MDA含量升高 (P <0 .0 1) ,SOD、GPx活力降低 (P <0 .0 1)。SO能显著减少损伤神经元的LDH漏出率及MDA的生成 (P <0 .0 1) ,升高SOD、GPx(P <0 .0 1)的活力 ,这种作用可被GABAA 受体阻断剂seurinine减弱 (P <0 .0 1)。结论 :SO对缺氧复氧神经元损伤的保护作用可能与其激动GABAA 受体有关。     

Stearic acid protects primary cultured cortical neurons against oxidative stress

AIM: To observe the effects of stearic acid against oxidative stress in primary cultured cortical neurons. METHODS: Cortical neurons were exposed to glutamate, hydrogen peroxide (H2O2), or NaN3 insult in the presence or absence of stearic acid. Cell viability of cortical neurons was determined by MTT assay and LDH release. Endogenous antioxidant enzymes activity[superoxide dismutases (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT)] and lipid peroxidation in cultured cortical neurons were evaluated using commercial kits. {3-[1(p-chlorobenzyl)- 5-(isopropyl)-3-t-butylthiondol-2-yl]-2,2-dimethylpropanoic acid, Na} [MK886; 5 micromol/L; a noncompetitive inhibitor of proliferator-activated receptor (PPAR) alpha], bisphenol A diglycidyl ether (BADGE; 100 micromol/L; an antagonist of PPAR gamma), and cycloheximide (CHX; 30 micromol/L, an inhibitor of protein synthesis) were tested for their effects on the neuroprotection afforded by stearic acid. Western blotting was used to determine the PPAR gamma protein level in cortical neurons. RESULTS: Stearic acid dose-dependently protected cortical neurons against glutamate or H2O2 injury and increased glutamate uptake in cultured neurons. This protection was concomitant to the inhibition of lipid peroxidation and to the promotion activity of Cu/Zn SOD and CAT in cultured cortical neurons. Its neuroprotective effects were completely blocked by BADGE and CHX. After incubation with H2O2 for 24 h, the expression of the PPAR gamma protein decreased significantly (P<0.05), and the inhibitory effect of H2O2 on the expression of PPAR gamma can be attenuated by stearic acid. CONCLUSION: Stearic acid can protect cortical neurons against oxidative stress by boosting the internal antioxidant enzymes. Its neuroprotective effect may be mainly mediated by the activation of PPAR gamma and new protein synthesis in cortical neurons.     

N-acetylcysteine protects against fluoride-induced oxidative damage in primary rat hepatocytes

Fluoride induces the overproduction of free radicals, which might in turn affect various biochemical parameters. Therefore, the aim of this study was to elucidate the role of N-acetylcysteine (NAC) in decreasing fluoride-induced oxidative stress. The fluoride intoxicated (0.002; 0.082; 0.164 mmol/l) rat hepatocytes was pre-treated (60 min) and simultaneously treated with NAC (1 mmol/l). The resulting levels of lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and intracellular reduced glutathione (GSH) were measured along with the total antioxidant status (TAS) to determine whether NAC treatment reduced cell damage and/or the antioxidant state. These results suggest that NAC pre-treatment provides protection against fluoride-induced oxidative stress in hepatocytes.     

15-Methoxypinusolidic acid from Biota orientalis attenuates glutamate-induced neurotoxicity in primary cultured rat cortical cells.

15-Methoxypinusolidic acid (15-MPA), a pinusolide derivative isolated from Biota orientalis (Cupressaceae) leaves prevented glutamate-induced excitotoxicity in primary cultured rat cortical cells in vitro. 15-MPA had more selectivity in protecting neurons against N-methyl-D-aspartate (NMDA)-induced neurotoxicity than that induced by kainic acid (KA). The glutamate-induced increase of intracellular calcium ([Ca2+]i) in cortical cells was effectively reduced by 15-MPA. Moreover, 15-MPA could successfully reduce the subsequent overproduction of nitric oxide (NO) and the level of cellular peroxide, and inhibit glutathione (GSH) depletion and lipid peroxidation induced by glutamate in our cultures. Collectively, these results suggested that 15-MPA attenuated glutamate-induced excitotoxicity via stabilization of [Ca2+]i homeostasis and suppression of oxidative stress possibly through the actions on the NMDA receptors.     

Big mitogen-activated protein kinase 1 protects cultured rat aortic smooth muscle cells from oxidative damage

Oxidative stress is considered a major mediator of arteriosclerosis. In vascular smooth muscle cells, oxidative stress-induced cell death (including apoptosis) is probably related to arterial calcification in arteriosclerosis. Big mitogen-activated protein kinase-1 / extracellular signal-regulated kinase 5 (BMK1/ERK5) is a newly identified member of the mitogen-activated protein kinases family. Like Src tyrosine kinase, BMK1/ERK5 is known to be sensitive to oxidative stress; however, its pathophysiological significance is poorly understood. In this study, we investigated the involvement of BMK1 and Src in H(2)O(2)-induced cell death using cultured rat aortic smooth muscle cells (RASMCs). Cell apoptosis was evaluated by using the TdT-mediated dUTP nick end labeling (TUNEL) method, and BMK1 and Src activities were determined by Western blotting. The main results are as follows: 1) BMK1 and Src were activated by H(2)O(2) in a time- and concentration-dependent manner in RASMCs; 2) BMK1 activation by H(2)O(2) was attenuated both in Src-knockdown RASMCs and in RASMCs pretreated with 4-amino-5-(4-chloro-phenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2), a Src family kinases inhibitor; and 3) H(2)O(2)-induced cell death was increased in BMK1- and Src-knockdown RASMCs as well as in PP2-treated RASMCs. These findings suggested that Src and BMK1 may play defensive and resistive roles against oxidative stress-induced death in RASMCs.     

Quercetin protects against ethanol-induced oxidative damage in rat primary hepatocytes

The pathogenesis and progression of alcoholic liver disease (ALD) are associated with free radical injury and oxidative stress, which could be partially attenuated by antioxidants and free radical scavengers. Quercetin, one of the most widely distributed flavonoids in plants, is a natural antioxidant. The hypothesis that quercetin could prevent the ethanol-induced oxidative damage in hepatocytes was investigated. The ethanol-intoxicated (100 mM for 8 h) rat primary hepatocytes were post-treated (2 h), simultaneously treated or pre-treated (2 h) with quercetin respectively, while the time-dependent (0.5–8 h) and dose-dependent (25–200 μM) quercetin pre-treatment were used in the present study. The parameters of lactate dehydrogenase (LDH), aspartate transaminase (AST), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were determined to address the alterations of cell damage and antioxidant state after quercetin intervention. The toxic insult of ethanol to hepatocytes was challenged by quercetin and these parameters almost returned to the level of control group when hepatocytes were pre-treated with quercetin at the dose of 50 μM for 2–4 h before ethanol exposure. In conclusion, quercetin pre-treatment provided protection against ethanol-induced oxidative stress in hepatocytes and may be used as a new natural drug for the prevention and/or treatment of ALD.     

Casuarinin protects cultured MDCK cells from hydrogen peroxide-induced oxidative stress and DNA oxidative damage

Casuarinin has been shown to be an antioxidant in acellular experiments. This study was designed to assess the ability of casuarinin, extracted from Terminalia arjuna, to protect cultured Madin-Darby canine kidney (MDCK) cells against H2O2-mediated oxidative stress. A comparison with trolox, a hydrosoluble vitamin E analogue was performed. MDCK cells were pretreated with casuarinin or trolox for 1 h, then exposed to H2O2. After incubation with 0.8 mM H2O2 for 1 h, casuarinin caused a decrease in intracellular peroxide production as shown by dichlorofluorescein (DCF) fluorescence in a concentration-dependent manner. After 3 h exposure to 8 mM H2O2, the percentage of intracellular glutathione (GSH)-negative cells was reduced in the casuarinin-treated group. Addition of 32mM H2O2 to MDCK cells for 3 h induced an increase in the percentage of cells containing 8-oxoguanine but the level of such cells declined in casuarinin-treated cells. These results show that casuarinin is more effective against H2O2-induced oxidative damage than trolox. The data suggest that casuarinin attenuates H2O2-induced oxidative stress, decreases DNA oxidative damage and prevents the depletion of intracellular GSH in MDCK cells.     

Rosmarinic acid inhibits chemical hypoxia-induced cytotoxicity in primary cultured rat hepatocytes

We examine the effect of rosmarinic acid (RA) in chemical hypoxia-induced injury in rat hepatocytes. Cell viability was significantly decreased by cobalt chloride (CoCl₂), a well-known hypoxia mimetic agent in a time- and dose- dependent manner. RA pretreatment before exposure to CoCl₂ significantly attenuated the CoCl₂-induced decrease of cell viability. Additionally, pretreatment with RA potentiated the decrease of Bcl-2 expression and attenuated the increase of Caspase-3 expression by CoCl₂. CoCl₂ treatment resulted in an increase of intracellular ROS generation, which is inhibited by RA or N-acetyl-cysteine (NAC, a ROS scavenger), and p38MAPK phosphorylation, which is also blocked by RA or NAC. CoCl₂-induced increase of Bax/Bcl-2 ratio and Caspase-3 expression was attenuated by RA, NAC and SB203580 (p38MAPK inhibitor). CoCl₂-induced decrease of cell viability was also attenuated by RA, NAC and SB203580 pretreatment. Additionally, RA inhibited CoCl₂-induced COX-2 expression and prostaglandin E2 (PGE₂) secretion. Similar to the effect of RA, both NAC and NS-398 (COX-2 inhibitor) blocked CoCl₂-induced COX-2 expression and PGE₂ secretion. NS-398 attenuated not only CoCl₂-induced increase of Bax/Bcl-2 ratio and Caspase-3 expression, but decrease of cell viability. Taken together, RA protects primary cultured rat hepatocytes against CoCl₂-induced cell injury through inhibition of ROS-activated p38MAPK and COX-2/PGE₂ pathway.     

Early oxidative damage in primary cultured trout hepatocytes: a time course study

The aim of this study was to evaluate the influence of the two-step hepatocyte isolation procedure on primary cultured trout (Oncorhynchus mykiss) hepatocytes over time. We characterised the possible changes of a variety of some cellular parameters within the first 24-48 h after seeding. We followed the time dependent changes of these parameters during subsequent culture times in order to see if the cells maintained a differentiated status. Scanning electron microscopy revealed bleb formation and 20% cell damage in freshly isolated hepatocytes. During subsequent culture times the bleb dimension appear to be reduced. Heat shock proteins 70 and 50 (HSP70, HSP50) were induced by hepatocyte isolation. During the first 4 h of culture, the hepatocytes showed a variation in mitochondrial activity, an increase in free radical species (ROS), and a decrease in both glutathione (GSH) content and catalase (CAT) activity; the generation of free radicals led to an increase in the formation of 8-hydroxydeoxyguanosine (8-OHdG) in the DNA. The cells showed detectable ethoxyresorufin-O-deethylase activity after 4 h of culture, which had rapidly increased by the 24th hour. After 24 h, mitochondrial and CAT activity, free radical production, and the content of GSH and 8-OHdG returned to their original levels. P450 activity was retained for at least 48 h after seeding. Our data show that trout hepatocytes suffer significant cell injury as a result of the isolation procedure, but primary cultured cells metabolically recover from this stress after a few hours: they are capable of repairing their damaged surfaces, recovering their antioxidant defences and retaining their ability to repair DNA. Our results also confirm that trout hepatocytes in a primary culture maintain their in vivo-like metabolic activities for 3-8 days.     

丹参多酚酸盐抑制培养大鼠系膜细胞增殖及内皮素释放

目的:研究丹参多酚酸盐对体外培养的大鼠系膜细胞增殖及内皮素释放的影响。方法：细胞增殖的测定用][^3H]-TdR掺入法;用放射免疫法测定细胞上清液中内皮素浓度的变化;细胞毒性的测定用MTT及LDH法。结果：LPS 10mg/L能诱导系膜细胞增殖及内皮素释放的增多。丹参多酚酸盐3、10及30mg/L与系膜细胞孵育4h,丹参多酚酸盐能浓度依赖性抑制由LPS诱导引起的系膜细胞增殖及内皮素释放的增多。丹参多酚酸盐30mg/L也能显著抑制系膜细胞4、8和12h时的增殖及内皮素的释放。丹参多酚酸盐对系膜细胞没有细胞毒作用。结论：丹参多酚酸盐能抑制大鼠系膜细胞的增殖,其机制可能与抑制内皮素的释放有关。     

Allopregnanolone attenuates kainate-induced toxicity in primary cortical neurons and PC12 neuronal cells

In this study, we demonstrated that allopregnanolone at 500 and 1000 nM significantly inhibited kainate-induced lactate dehydrogenase release from primary cortical cells by ca. 25 and 50%, respectively. Furthermore, allopregnanolone doses of 100 and 500 nM decreased cytotoxic effects of kainate (150 microM, 24-hour exposure) in PC12 neuronal cells by about 55 and 37%, respectively. These data strongly support neuroprotective effects of allopregnanolone observed in vivo.     

海兔素对大鼠原代肝细胞酒精性氧化损伤的保护作用

目的探讨海兔素对大鼠原代肝细胞酒精性氧化损伤保护作用。方法门静脉胶原酶Ⅳ原位灌注及密度梯度离心获得大鼠原代肝细胞。MTT实验检测乙醇和海兔素最佳作用剂量及肝细胞活力。酶学实验检测细胞AST、LDH、SOD、MDA、GSH水平;流式细胞术检测细胞凋亡情况;单细胞凝胶电泳观察细胞DNA损伤状况;JC-1荧光探针检测细胞线粒体膜电位水平;比色法及Western blot检测细胞CYP2E1活性及蛋白表达。结果经30 mg·L~(-1)。海兔素预作用2 h,再与300 mmol·L~(-1)。乙醇共作用8 h后,肝细胞活力较酒精模型组明显上升,AST和LDH释放也得到明显抑制;同时,肝细胞SOD和GSH水平明显升高,MDA含量则明显降低,差异均具有显著性(P<0.05)。海兔素干预后,肝细胞凋亡率明显降低,DNA损伤及线粒体膜电位水平明显得到改善。海兔素干预后,肝细胞CYP2E1活性及蛋白表达水平明显受到抑制(P<0.05)。结论海兔素对大鼠原代肝细胞酒精性氧化损伤具有保护作用,其作用机制可能与海兔素抑制酒精对CYP2E1的活化,缓解氧化应激,提高机体抗氧化能力有关。     

丁基苯酞对氯化钾及 N-甲基-D-门冬氨酸诱导的大鼠皮质神经细胞损伤的保护作用

用原代培养大鼠皮质神经细胞的方法,观察l-丁基苯酞(l-NBP)和d-丁基苯酞(d-NBP)对KCl及N-甲基-D-门冬氨酸(NMDA)诱导的大鼠皮质神经细胞损伤的保护作用。结果表明:l-NBP和d-NBP能剂量依赖性地抑制NMDA诱导的大鼠皮质神经细胞内乳酸脱氢酶的释放,降低细胞死亡率,改善受损细胞的形态;此外l-NBP和d-NBP还能明显减轻KCl诱导的神经细胞损伤。提示:l-NBP和d-NBP对KCl及NMDA诱导的大鼠皮质神经细胞损伤有明显保护作用。     

Fenvalerate inhibits the growth of primary cultured rat preantral ovarian follicles

Fenvalerate is a widely used synthetic pyrethroid insecticide and is reported to disrupt reproductive function in humans and animals. However, little is known about its influence on follicular development. In this study, rat preantral follicles were primary cultured to investigate the effects of fenvalerate on follicular survival rate, morphological change, steroid hormone levels and steroidogenesis related gene mRNA expression. Follicles were cultured with 0, 1, 5 and 25 μmol/L fenvalerate for 72 h. And then the morphous was assessed by conventional light microscopy, steroid hormones were measured by RIA, and the expressions of steroidogenic acute regulatory protein (StAR) and cytochrome P450 side-chain cleavage enzyme (P450scc) were monitored by real-time quantitative PCR analysis. Results showed that fenvalerate inhibited the augmentation of follicular diameters but did not have detectable effects on follicular survival rates. The level of steroid hormones, such as progesterone, testosterone and estradiol, was inhibited. The inhibition might be due to the decreased expression levels of StAR and P450scc. These results suggested that fenvalerate restrained the follicular growth, and inhibited steroidogenesis by reducing StAR and P450scc gene expression, which might further contribute to the fenvalerate-induced reproductive dysfunction.