黄芩苷对庆大霉素致小鼠耳蜗螺旋神经节细胞毒性拮抗作用

目的:探讨黄芩苷(baicalin,BA)对庆大霉素(gentamicin,GM)致小鼠耳蜗螺旋神经节(spiralganglion,SG)细胞毒性作用 的拮抗机制。方法:用紫外分光光度法分别测定各实验组小鼠SG细胞中总超氧化物歧化酶(T SOD)活性及丙二醛(MDA)含量。 结果:黄芩苷可显著抑制GM所导致的SG细胞中T SOD活性降低及MDA含量升高。结论:黄芩苷通过清除氧自由基和抗脂质 过氧化作用,拮抗庆大霉素致耳蜗螺旋神经节细胞毒性作用。     

微渗透压泵耳蜗灌注bFGF对庆大霉素所致豚鼠耳毒的拮抗作用

目的：应用微渗透压泵将碱性成纤维细胞因子(bFGF)导入耳蜗，观察其对庆大霉素所致活体耳蜗毒性的拮抗作用。方法：豚鼠皮下注射庆大霉素造成耳毒性聋的模型。实验将bFGF以微渗透压泵导入实验组右耳蜗，对照组右耳以微渗透压泵导入等量PBS。用扫描电镜观察两组动物右耳毛细胞的损伤，同时比较其用药前后ABR听阈的改变。结果：对照组右耳的损伤明显重于实验组。结论：采用微渗透压泵耳蜗灌注bFGF对庆大霉素所致豚鼠的耳蜗损伤有拮抗作用。     

螺旋神经节社会元体外培养及提高细胞产率和活性的探讨

目的：在体外建立大鼠耳蜗螺旋神经节神经元培养模型，并提高其产出率及细胞活性。方法：将出生后5天的大鼠耳蜗螺旋神经节神经元在体外培养3－5天，用神经丝蛋白（Neurofilament protein,NFP)单克隆抗体进行免疫组化染色。结果：显示耳蜗螺旋神经节社会元在体外无血清培养条件下，可以存活并进行正常分化。结论：耳蜗螺旋神经节神经元在体外有稳定的可塑性及轴突再生修复能力。     

螺旋神经节神经元体外培养及提高细胞产率和活性的探讨

目的在体外建立大鼠耳蜗螺旋神经节神经元培养模型,并提高其产出率及细胞活性.方法将出生后5天的大鼠耳蜗螺旋神经节神经元在体外培养3～5天,用神经丝蛋白(Neurofilamentprotein,NFP)单克隆抗体进行免疫组化染色.结果显示耳蜗螺旋神经节神经元在体外无血清培养条件下,可以存活并进行正常分化.结论耳蜗螺旋神经节神经元在体外有稳定的可塑性及轴突再生修复能力.     

加减味耳聋左慈丸对耳蜗琥珀酸脱氢酶的保护作用

目的:观察中药方剂"耳聋左慈丸"加减味对庆大霉素(GM)耳毒性的防治作用,并探讨其作用机制.方法:用脑干听觉诱发电位(BAEP)的方法检测GM耳中毒豚鼠听阈的变化;用组织化学的方法检测耳蜗毛细胞线粒体内琥珀酸脱氢酶(SDH)的变化.结果:该中药方剂能降低GM引起的听觉反应阈的上升幅度,减轻GM对耳蜗毛细胞SDH损害,降低了对毛细胞的损伤.结论:该中药方剂具有明显保护耳蜗毛细胞SDH,降低GM的耳毒性的作用.保护耳蜗毛细胞线粒体SDH,维持了毛细胞的能量代谢及其功能,从而减轻了毛细胞损伤,这可能是该方剂降低GM耳毒性的机制之一.     

人参二醇组皂苷减轻庆大霉素性肾损伤机制研究

目的:研究人参二醇组皂苷(PDS)减轻庆大霉素(GM)性肾损伤的机制。方法:建立GM性肾小管细胞损伤模型,以MTT法观察PDS对肾小管细胞增殖的影响,以生化法检测PDS对肾小管细胞内超氧化物歧化酶(SOD)、丙二醛(MDA)含量和培养上清液中乳酸脱氢酶(LDH)含量的影响。结果:PDS可促进GM损伤肾小管细胞的增殖,显著降低其MDA和LDH含量,提高SOD活性(P<0.05)。结论:PDS可能通过促进肾小管细胞的增殖和抑制脂质过氧化反应,加快自由基的清除,增加生物膜的稳定性,从而减轻GM性肾小管损伤。     

阿魏酸钠对异烟肼和利福平肝损害小鼠的保护作用

目的：观察阿魏酸钠对异烟肼(INH)和利福平(RFP)肝毒性的保护作用。方法：分别测定血清谷丙转氨酶(ALT)的活性，肝匀浆中谷胱甘肽(GSH)及脂质过氧化物丙二醛(MDA)的含量，肝微粒体中细胞色素P450及其亚型2E1的活性。结果：阿魏酸钠可对抗INH和RFP合用引起的肝指数、血清ALT水平、肝匀浆中的MDA含量，以及细胞色素P450与亚型P450 2E1活性的升高，增加肝匀浆中GSH含量。病理学检查，阿魏酸钠明显减轻肝细胞的变性和坏死。结论：阿魏酸钠时INH和RFP肝毒性的保护作用与保护肝细胞膜、抑制脂质过氧化反应、清除自由基、降低RFP诱导的细胞色素P450酶系统有关。     

赖氨酸阿司匹林对庆大霉素耳毒性的保护作用

目的探讨庆大霉素与赖氨酸阿司匹林混合用药对庆大霉素耳毒性的保护作用。方法健康♂豚鼠30只,随机分为3组:庆大霉素(GM)组、庆大霉素联合赖氨酸阿司匹林(GM LAP)组和对照组。GM组:12mg·kg-1,sc,qd;GM LAP组:GM 12 mg·kg-1 LAP 135 mg·kg-1,sc,qd。对照组:不给予任何药物。采用听性脑干反应(ABR)和耳蜗铺片观察用药前后听阈及耳蜗毛细胞形态学改变。结果GM组1、8 kHz ABR4 wk平均阈移与GM LAP组间差异有统计学意义(P<0．05)。耳蜗铺片结果显示,GM组底圈毛细胞有损伤,与正常组比较排列不整齐,毛细胞损伤向上逐渐减轻,与听阈升高的程度相平行;而GM LAP组的毛细胞排列整齐,无损伤。结论赖氨酸阿司匹林对庆大霉素耳毒性有保护作用。     

神经节苷脂GM1对谷氨酸介导的基底前脑神经元损伤的保护作用

目的 观察神经节苷脂GM1对谷氨酸造成的基底前脑神经元损伤的保护作用.方法 取出生后1 d乳鼠前脑基底神经元培养,随机分为正常对照组、模型组(谷氨酸损伤组)、神经节苷脂GM1保护组.用倒置相差显微镜进行活细胞观察,采用RT-PCR技术检测前脑基底神经元神经生长相关蛋白-43(Growth associated protein-43,GAP-43)的表达.结果 谷氨酸损伤组神经元在倒置相差显微镜下可见胞体回缩,突起消失或断裂.神经节苷脂GM1保护组的神经元绝大多数胞体饱满,突起明显,细胞间的网络联系仍清晰可见,接近于正常对照组;神经节苷脂GM1大脑基底神经节GAP-43的mRNA表达比谷氨酸损伤组高,两者比较差异有统计学意义(P＜0.05).结论 神经节苷脂GM1能保护基底神经元免受谷氨酸兴奋性毒性的损伤.     

黄芩苷衍生物的合成及其生物活性研究

目的为改善黄芩苷的溶解性,设计合成系列黄芩苷衍生物,并评价其抗脂质过氧化活性和抗肿瘤活性。方法以黄芩苷和环氧乙(丙)烷为原料,通过羟乙基化、羟丙基化、酯化反应合成了一系列黄芩苷衍生物;分别采用生化法和台盼蓝染色法测试目标化合物对小鼠脑脂质过氧化产物丙二醛(MDA)的体外抑制作用及对白血病细胞HL-60的生长抑制活性。结果合成了13个黄芩苷衍生物,其结构经1H-NMR和MS确证。其中,化合物3⁶、116、11¹3为未见文献报道的新化合物。化合物1、6对MDA的抑制作用显著,化合物713为未见文献报道的新化合物。化合物1、6对MDA的抑制作用显著,化合物7¹0、12具有中等强度的抑制HL-60生长作用。结论黄芩苷结构中的酚羟基是其抑制脂质过氧化产物MDA的活性基团,葡萄糖醛酸的6位游离羧基是能够增强化合物抗肿瘤活性的有效基团。     

Ethanol extract of Piper longum L. attenuates gentamicin-induced hair cell loss in neonatal cochlea cultures

Piper longum L. (PL), also as known as long pepper, a well-known spice and traditional medicine in Asia and Pacific islands, has been reported to exhibit wide spectrum activity including antioxidant activity. However, little information is available on its protective effect on gentamicin (GM) induced ototoxicity which is commonly regarded as being mediated by reactive oxygen species and reactive nitrogen species. This study was undertaken to investigate the protective effect of PL ethanol extract on gentamicin-induced hair cell loss in neonatal cochlea cultures. Cochlea cultures from postnatal day 2-3 mice were used for analysis of the protective effects of PL against gentamicin-induced hair cell loss by phalloidin staining. E. coil cultures were used to determine whether PL interferes with the antibiotic activity of GM. Nitric oxide (NO)-scavenging activity of PL was also measured in vitro. GM induced significant dose-dependent hair cell loss in cochlea cultures. However, without interfering with the antibiotic activity of GM, PL showed a significant and concentration-dependent protective effect against GM-induced hair cell loss, and hair cells retained their stereocilia well. In addition, PL expressed direct scavenging activity toward NO radical liberated within solution of sodium nitroprusside. These findings demonstrate the protective effect of PL on GM-induced hair cell loss in neonatal cochlea cultures, and suggest that it might be of therapeutic benefit for treatment of GM-induced ototoxicity.     

Protective effects of amino acids against gabexate mesilate-induced cell injury in porcine aorta endothelial cells

Gabexate mesilate (GM), a serine protease inhibitor, often causes severe vascular injury. We previously reported that GM induced necrotic cell death via injury of the cell membrane in porcine aorta endothelial cells (PAECs). In the present study, we investigated the protective effects of amino acids against this GM-induced cell injury in PAECs. L-Cysteine (Cys), glycine (Gly), L-serine, L-glutamine (Gln), L-glutamate (Glu), L-proline, L-methionine, L-threonine, and L-isoleucine significantly inhibited the GM-induced decrease of cell viability. Gly showed the most potent effect among these amino acids. Gly, L-Cys, L-Glu, and L-Gln also inhibited the GM-induced increase in the number of necrotic cells stained by propidium iodide (PI). However, these amino acids had no effect on the GM-induced inhibition of trypsin activity. Strychnine, MK-801, or dichlorokynurenic acid did not affect the protective effect of Gly. Gly completely suppressed the GM-induced increase in PI uptake, which occurred immediately after exposure to GM. These findings suggest that Gly exerts protection against GM-induced cellular membrane injury, and several amino acids such as Gly may be useful for prophylaxis of the GM-induced severe vascular injury.     

Protective effects of oral arabic gum administration on gentamicin-induced nephrotoxicity in rats.

Arabic gum (AG) is a complex polysaccharide used as suspending agent. It has been widely used by eastern folk medicine practitioners as a restorative agent and is thought to be an excellent curative for renal failure patients. We therefore tested these folkloric claims using a rat model of gentamicin (GM)-induced nephrotoxicity. AG (7.5g 100ml(-1), in drinking water) was administered orally for 8 days concurrently with GM (80mgkg(-1) per day, i.p.). Estimation of urine volume, serum creatinine and urea concentrations, kidney tissue malondialdehyde (MDA) contents and glutathione (GSH) were carried out after the last dose of GM. Kidneys were also examined for histological changes. GM caused a marked nephrotoxicity as evidenced by significant increases in urine volume (295%), serum creatinine (318%) and urea (258%) and a significant decrease in creatinine clearance (Ccr) (26%). Treatment with AG protected the rats from GM-induced nephrotoxicity as evident by normalisation of these parameters. In addition there was about 187% increase in kidney tissue MDA contents above the control with GM treatment. AG totally prevented the GM-induced rise in kidney tissue contents of MDA. Kidney histology of the tissue from GM-treated rats showed necrosis and desquamation of tubular epithelial cells in renal cortex as well as interstitial nephritis. Whereas it was very much comparable to control when AG was co-administered with GM. In conclusion, AG protected the rats from GM-induced nephrotoxicity, possibly, at least in part through inhibition of the production of oxygen free radicals that cause lipid peroxidation.     

Protective role of pyrroloquinoline quinone against gentamicin induced cochlear hair cell ototoxicity

Gentamicin (GM) is one of the commonly used antibiotics in the aminoglycoside class but is ototoxic, which constantly impacts the quality of human life. Pyrroloquinoline quinone (PQQ) as a redox cofactor produced by bacteria was found in soil and foods that exert an antioxidant and redox modulator. It is well documented that the PQQ can alleviate inflammatory responses and cytotoxicity. However, our understanding of PQQ in ototoxicity remains unclear. We reported that PQQ could protect against GM-induced ototoxicity in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells in vitro. To evaluate reactive oxygen species (ROS) production and mitochondrial function, ROS and JC-1 staining, oxygen consumption rate (OCR), and extracellular acidification rate (ECAR) measurements in living cells, mitochondrial dynamics analysis was performed. GM-mediated damage was performed by reducing the production of ROS and inhibiting mitochondria biogenesis and dynamics. PQQ ameliorated the cellular oxidative stress and recovered mitochondrial membrane potential, facilitating the recovery of mitochondrial biogenesis and dynamics. Our in vitro findings improve our understanding of the GM-induced ototoxicity with therapeutic implications for PQQ.     

异甘草酸镁对D-氨基半乳糖急性肝损伤模型小鼠的保护作用研究

目的研究异甘草酸镁对D-氨基半乳糖急性肝损伤模型小鼠的保护作用。方法以D-氨基半乳糖建立小鼠急性肝损伤模型,分别设正常对照组、病理模型组、异甘草酸镁高、低剂量组以及美能组、易善复组、凯西莱组,测定各组小鼠血清中丙氨酸氨基转移酶(ALT)、天门冬酸氨基转移酶(AST)活性及肝组织中丙二醛(MDA)、黄嘌呤氧化酶(XOD)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、总抗氧化能力(T-AOC)、一氧化氮(NO)、一氧化氮合成酶(NOS)、诱生型一氧化氮合酶(iNOS)含量。另以HE染色,采用光镜对各组小鼠肝脏作病理检查。结果异甘草酸镁可明显降低ALT、AST的活性(P<0.01)及肝组织中MDA、XOD、NO、NOS、iNOS的含量;升高肝组织中SOD、GSH-PX、T-AOC的含量。光镜下可观察到异甘草酸镁能减轻小鼠肝脏坏死性病理改变。结论异甘草酸镁对D-氨基半乳糖诱导的小鼠急性肝损伤具有良好的保护作用。     

Protective effects of vitamin e and probucol against gentamicin-induced nephrotoxicity in rats.

Gentamicin (GM) is widely used as a bactericidal agent for the treatment of severe gram negative infections, however, its clinical use is partially limited due to its nephrotoxicity. Recent evidence suggests a role of reactive oxygen metabolites in GM nephrotoxicity. The present study was designed to investigate a possible potential protective role of vitamin E and/or probucol against GM nephrotoxicity. GM was administered to rats in a single dose of (150 mg kg(-1)i.p.), while vitamin E (250 mg kg(-1)i.m.) and/or probucol (60 mg kg(-1)i.m.) were given once daily for 3 consecutive days prior to GM administration. GM-induced nephrotoxicity was evidenced by marked elevations in serum urea and creatinine levels, urinary activity of N-acetyl-beta- d -glucosaminidase (NAG) and gamma-glutamyl-transferase (gamma-GT). Also, GM caused significant increases in kidney content of malondialdehyde (MDA), and significant decreases in kidney content of reduced non-protein sulphydryls (NPSH) and superoxide dismutase (SOD) activity. Vitamin E pretreatment significantly lowered the elevated serum urea and creatinine levels, and urinary activity of NAG and gamma-GT. In addition, vitamin E ameliorated the rise in renal content of MDA and enhanced the renal NPSH content as well as SOD activity. Similarly, probucol significantly inhibited the elevations in urea and creatinine levels and enhanced renal NPSH content and SOD activity. Simultaneous use of vitamin E and probucol was more effective in mitigating disturbances in the assessed parameters. The present work indicates that, due to their antioxidant activity, vitamin E and probucol have potential protective effects against GM nephrotoxicity. 1999 Academic Press Copyright 1999 Academic Press.     

松树皮中原花青素对荷瘤小鼠S_(180)肿瘤细胞抗氧化酶系的影响

目的研究松树皮中原花青素的体内抗肿瘤作用.方法采用小鼠移植性肿瘤模型S180肉瘤考察松树皮原花青素对荷瘤小鼠瘤重的抑制作用,紫外分光光度法测定原花青素对肿瘤细胞CuZn-SOD、GSH-PX活性以及MDA含量的影响,流式细胞仪检测原花青素对肿瘤细胞中活性氧含量的影响.结果松树皮原花青素对肿瘤细胞有较强的抑制作用,120mg·kg-1的剂量能显著抑制荷瘤小鼠S180肉瘤的生长,抑瘤率达49.73%;对S180肿瘤细胞中CuZn-SOD、GSH-PX活性有一定的作用,其中高剂量能够显著性的提高其活性;能够降低肿瘤细胞中MDA的含量,防止脂质过氧化的发生.结论松树皮原花青素通过抑制肿瘤的生长,保护正常细胞,减少自由基对正常细胞的伤害而达到抗肿瘤作用.     

黄芩素对人肝癌HepG2细胞生长的抑制作用

目的:研究黄芩素对人肝癌Hep G2细胞生长的抑制作用。方法:在培养Hep G2细胞的96孔板上加入药物,使黄芩素的终浓度分别为0、20、40、80、160μmol/L(即对照组与黄芩素1、2、3、4组)。采用MTT法检测细胞的存活情况,分光光度法检测含半胱氨酸的天冬氨酸蛋白水解酶(Caspase)-3、8、9的活性,并检测丙二醛(MDA)含量,超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性。结果:与对照组比较,培养24、48、72 h时,黄芩素2、3、4组各时间点的吸光度降低;培养24 h时,Caspase-3、8、9活性增强,MDA含量增加,SOD、GSH-Px活性减弱,差异均有统计学意义(P<0.01)。结论:黄芩素对Hep G2细胞生长具有抑制作用,其机制与增强Caspase-3、8、9活性,增加MDA含量,减弱SOD、GSH-Px活性有关。     

香青兰及其含药血清对H9c2心肌细胞三种缺氧/复氧损伤模型的影响

目的:比较香青兰醇提物及其含药血清对H9c2心肌细胞3种缺氧/复氧损伤模型的影响,考察香青兰对心肌缺血/再灌注损伤的保护作用。方法:体外培养H9c2心肌细胞,以Na2S2O4,N2和厌氧袋为缺氧环境分别建立缺氧/复氧损伤模型,以T-SOD,MDA,LDH为指标,考察香青兰醇提物(1,10,100μg.mL-1)及其含药血清对H9c2心肌细胞缺氧/复氧损伤的影响。结果:与模型组比较,香青兰醇提物及其含药血清能明显抑制缺氧/复氧损伤H9c2心肌细胞LDH释放和MDA含量,升高T-SOD活力(P<0.05或0.01)。结论:香青兰醇提物及其含药血清对H9c2心肌细胞缺氧/复氧损伤具有保护作用,提示香青兰具有保护心肌缺血/再灌注损伤的作用。