Pyridostigmine bromide and its relation to Gulf War illness

Abstract

Pyridostigmine bromide acts as a reversible cholinesterase inhibitor that is used at relatively high doses in treatment of Myasthenia gravis and in low dose regimens as prophylaxis against nerve agents poisoning during the Gulf War. The manifestation of late nonspecific symptoms commonly called Gulf War illness has led to the discussion about the role of pyridostigmine bromide in the pathogenesis of this illness. In our study, we described plasma absorption profile of pyridostigmine bromide after p.o. administration in rats; subsequently, changes in blood biochemical and oxidative stress markers were measured. Pyridostigmine bromide was applied p.o. at the dose of 5.82?mg/kg b.w. according to the previously published recommendations. The absorption of pyridostigmine was relatively fast; the C_max in plasma was 110.20?±?15.12?ng/ml at T_max of 197.12?±?17.14?min. The bioavailability expressed as AUC_total was 44,348?±?7608?min ng/ml. The prolongation of pyridostigmine in circulation is in agreement with relatively long half-life that was 179.00?±?28.54?min. Several blood biochemical markers were altered, including glucose, creatinine, creatine kinase, alanine aminotransferase, aspartate aminotransferase, interleukin-6, triglycerides, and cholesterol. However, the changes could be considered as mild. Thiobarbituric acid reactive substances and ferric reducing ability of plasma indicate suppression of basal metabolism. The results of blood biochemical and oxidative stress markers imply that long-term use might possibly change the basal metabolism and cause cellular damage with inflammatory changes.     

Evaluation of fosphenytoin,levetiracetam, and propofol as treatments for nerve agent-induced seizures in pediatric and adult rats

Multiple recent instances of nerve agent (NA) exposure in civilian populations have occurred, resulting in a variety of negative effects and lethality in both adult and pediatric populations. Seizures are a prominent effect of NAs that can result in neurological damage and contribute to their lethality. Current anticonvulsant treatments for NAs are approved for adults, but no approved pediatric treatments exist. Further, the vast majority of NA-related research in animals has been conducted in adult male subjects. There is a need for research that includes female and pediatric populations in testing. In this project, adult and pediatric male and female rats were challenged with sarin or VX and then treated with fosphenytoin, levetiracetam, or propofol. In this study, fosphenytoin and levetiracetam failed to terminate seizure activity when animals were treated 5 min after seizure onset. Propofol was effective, exhibiting high efficacy and potency for terminating seizure activity quickly in pediatric and adult animals, suggesting it may be an effective anticonvulsant for NA-induced seizures in pediatric populations.     

Comparison of dendritic cells obtained from autoimmunty-prone and resistant rats

Dendritic cells (DC) are responsible for the initiation and shaping of the adaptive immune response and are in the focus of autoimmunity research. We were interested in comparison of DC obtained from autoimmunity-prone Dark Agouti (DA) rats and autoimmunity-resistant Albino Oxford (AO) rats. DC were generated from bone marrow precursors and matured (mDC) by lipopolysaccharide. Tolerogenic DC (tolDC) obtained by vitamin D3 treatment were studied in parallel. Profile of cytokine production was different in AO and DA mDC and tolDC. Expression of MHC class II molecules and CD86 were higher in DA DC, while vitamin D3 reduced their expression in dendritic cells of both strains. Allogeneic proliferation of CD4⁺ T cells was reduced by AO tolDC, but not with DA tolDC in comparison to respective mDC. Finally, expression of various genes identified as differentially expressed in human mDC and tolDC was also analyzed in AO and DA DC. Again, AO and DA DC differed in the expression of the analyzed genes. To conclude, AO and DA DC differ in production of cytokines, expression of antigen presentation-related molecules and in regulation of CD4⁺ T proliferation. The difference is valuable for understanding the divergence of the strains in their susceptibility to autoimmunity.     

基于代谢组学探讨艾灸关元穴对老年大鼠肾能量代谢的影响＊

目的 通过UHPLC-Q-TOF-MS代谢组学探讨艾灸关元穴对老年大鼠肾代谢物的影响，进而为艾灸关元穴的作用机制提供参考。方法 将8月龄SD雄性大鼠设为成年对照组（8只），21月龄SD雄性大鼠随机分为老年对照组（8只）、老年金匮肾气丸组（7只）、老年艾灸组（8只）。老年金匮肾气丸组每日按体重给药，老年艾灸组每日艾灸关元穴15 min，均每周5天。实验持续13周后检测大鼠肾组织线粒体呼吸耗氧速率、琥珀酸脱氢酶（SDH）活性以及血清肾功能指标，观察肾脏病理变化，结合UHPLC-Q-TOF-MS技术对大鼠的肾组织进行代谢轮廓分析，筛选代谢差异物并进行鉴定。结果 与老年对照组比较，老年艾灸组大鼠肾线粒体的呼吸耗氧速率和SDH酶的活力显著提高（P<0.01）。代谢组学结果显示，肾组织中筛选出13个共同差异化合物，分别是丁酸十二烷基酯、亚油酰胺、5-甲基四氢叶酸、PC（16∶0/22∶5（7Z，10Z，13Z，16Z，19Z））、6，8-二羟基嘌呤、1，2，3-丙烷三羧酸、3-（4-甲氧基苯基）-2-氧代丙酸、吲哚-3-乙酰甘氨酸、亚麻油酸、9，10-环氧十八烷酸、二十二碳五烯酸（22n-6）、牛磺胆酸、LysoPS （18∶0/0∶0）。结论 艾灸关元穴可通过调控老年大鼠的牛磺酸和亚牛磺酸代谢、α-亚麻酸代谢、亚油酸代谢、甘油磷脂代谢来调节肾的能量代谢。     

疏肝化瘀益气法对肝纤维化大鼠HIF-1α、VEGF表达的影响

目的研究疏肝化瘀益气法干预肝纤维化大鼠模型过程中,对大鼠肝脏组织HIF-1α、VEGF表达的影响。方法采用无菌猪血清诱导大鼠肝纤维化模型。随机分为3组。空白组、模型组给予生理盐水灌胃;软肝散干预组自造模开始即给予软肝散生药水煎剂灌胃。采用HE染色和Masson染色观察肝组织纤维化程度,RT-PCR、Western bolt检测肝组织中HIF-1α、VEGF蛋白的表达情况。结果与模型组相比,软肝散干预组肝组织中HIF-1α、VEGF表达显著下调(P<0.05或P<0.01)。且随着干预给药时间的延长,其表达量逐渐降低。结论以疏肝化瘀益气法为指导的软肝散可以改善肝纤维化的病理改变,通过下调HIF-1α、VEGF表达,抑制HIF-1α、VEGF的过表达,调控HIF-1α/VEGF信号通路抑制肝组织纤维化进程,从而发挥抗纤维化的作用。     

黄芪桂枝五物汤对神经病理性疼痛大鼠脊髓CX3CR1表达的影响

目的研究黄芪桂枝五物汤对神经病理性疼痛大鼠的镇痛作用及对脊髓背角和背根节中脊髓小胶质细胞趋化因子受体1(CX3CR1)表达的影响。方法将50只SD大鼠随机分为模型组、黄芪桂枝五物汤高剂量组、黄芪桂枝五物汤中剂量组、黄芪桂枝五物汤低剂量组、塞来昔布组,每组10只。所有大鼠均建立坐骨神经慢性缩窄性损伤神经病理性疼痛模型,术后模型组给予生理盐水10 mL/kg灌胃,黄芪桂枝五物汤高、中、低剂量组分别给予黄芪桂枝五物汤0.2 mL/kg、0.1 mL/kg、0.05 mL/kg灌胃,塞来昔布组给予塞来昔布30 mg/kg灌胃,均1次/d,连续14 d。分别在造模前及术后3,5,7,14 d采用热刺痛仪测定各组大鼠的热缩足反射潜伏期,用免疫组化法检测各组大鼠脊髓背角和背根节中CX3CR1表达情况,用荧光定量PCR法和Western blot法分别检测脊髓背角和背根节中CX3CR1 mRNA和蛋白的相对表达量。结果术后3 d各组大鼠热缩足反射潜伏期均较术前1 d明显缩短(P均<0.05),但模型组和塞来昔布组术后各时间段比较差异无统计学意义(P均>0.05);黄芪桂枝五物汤低、中剂量组从术后7 d开始、黄芪桂枝五物汤高剂量组从术后3 d开始热缩足反射潜伏期均明显长于模型组(P均<0.05)。免疫组化显示黄芪桂枝五物汤各剂量组脊髓背角和背根节中CX3CR1阳性细胞均显著少于模型组和塞来昔布组(P均<0.05),且黄芪桂枝五物汤高剂量组均明显少于黄芪桂枝五物汤低、中剂量组(P均<0.05),黄芪桂枝五物汤低、中剂量组间比较差异无统计学意义(P均>0.05)。模型组和塞来昔布组脊髓背角和背根节中CX3CR1 mRNA和蛋白相对表达量比较差异无统计学意义(P均>0.05);黄芪桂枝五物汤各剂量组脊髓背角和背根节中CX3CR1 mRNA和蛋白相对表达量均显著低于模型组和塞来昔布组(P均<0.05),且黄芪桂枝五物汤高剂量组均明显低于黄芪桂枝五物汤低、中剂量组(P均<0.05),黄芪桂枝五物汤低、中剂量组间比较差异无统计学意义(P均>0.05)。结论黄芪桂枝五物汤对神经病理性疼痛模型大鼠具有显著镇痛作用,其可能通过调控脊髓背角和背根节CX3CR1的表达发挥作用,且呈一定剂量依赖性。     

丹皮酚对去卵巢骨质疏松大鼠叉头框蛋白O3a/Wnt信号通路及椎骨密度的影响

背景:丹皮酚可抑制炎症,减轻慢性骨关节炎临床症状,作为一种不良反应小、更为安全的天然药物成分,探讨其对骨质疏松症的治疗作用具有重要的临床意义。目的:探究丹皮酚对去卵巢骨质疏松大鼠叉头框蛋白O3a(forkhead box O3a,FoxO3a)/Wnt信号通路及椎骨密度的影响。方法:雌性SD大鼠随机分为6组,每组10只。假手术组仅切除卵巢旁部分脂肪组织;其余50只大鼠均采用双侧卵巢摘除法制备去卵巢骨质疏松大鼠模型,模型制备成功后分为模型组、雌激素组[炔雌醇10μg/(kg·d)]、丹皮酚低、中、高剂量组[丹皮酚125,250,500 mg/(kg·d)],每组10只,灌胃给药;假手术组、模型组灌胃等量生理盐水,持续干预12周。ELISA法测定血清雌激素、骨保护素、骨钙素水平;采用双能X射线动物骨密度测定仪检测大鼠股骨及椎骨骨密度;采用骨科生物力学测试仪检测大鼠股骨及椎骨生物力学指标:弹性模量、最大载荷、屈服载荷;实时荧光定量PCR检测椎骨组织FoxO3a、Wnt2 mRNA表达水平;免疫印迹法检测椎骨组织FoxO3a、Wnt2及核内β-catenin蛋白表达。结果与结论:①治疗后,与假手术组比较,模型组L4,5骨密度、弹性模量、最大载荷、屈服载荷、血清雌二醇、骨保护素水平、椎骨组织Wnt2 mRNA及蛋白水平、核内β-catenin蛋白水平均显著降低(P<0.05),骨钙素水平、椎骨组织FoxO3a mRNA及蛋白水平显著增加(P<0.05);②与模型组比较,丹皮酚低、中、高剂量组大鼠L4,5骨密度、弹性模量、最大载荷、屈服载荷、血清雌二醇、骨保护素水平、椎骨组织Wnt2 mRNA及蛋白水平、核内β-catenin蛋白水平依次增加(P<0.05),血清骨钙素水平、椎骨组织FoxO3a mRNA及蛋白水平依次降低(P<0.05),且丹皮酚高剂量组均优于雌激素组(P<0.05);③提示丹皮酚可增加去卵巢骨质疏松大鼠椎骨骨密度,改善其骨生物力学状况,减轻骨质疏松,该作用可能与抑制FoxO3a、促进Wnt2/β-catenin通路激活有关。     

In vivo antimalarial activity and toxicological effects of methanolic extract of Cocos nucifera (Dwarf red variety) husk fibre

OBJECTIVE: Phytochemical constituents as well as antimalarial and toxicity potentials of the methanolic extract of the husk fi bre of Dwarf Red variety of Cocos nucifera were evaluated in this study.METHODS: The dried powdered husk fi bre was exhaustively extracted with hexane, ethyl acetate and methanol successively and the methanolic extract was screened for fl avonoids, phenolics, tannins, alkaloids, steroids, triterpenes, phlobatannins, anthraquinones and glycosides. A 4-day suppressive antimalarial test was carried out using Plasmodium berghei NK65-infected mice, to which the extract was administered at doses of 31.25, 62.5, 125, 250 and 500 mg/kg body weight(BW). Toxicity of the extract was evaluated in rats using selected hematological parameters and organ function indices after orally administering doses of 25, 50 and 100 mg/kg BW for 14 d.RESULTS: Phytochemical analysis revealed the presence of alkaloids, tannins, phenolics, saponins, glycosides, steroids and anthraquinones in the extract. Moreover, the extract reduced parasitemia by 39.2% and 45.8% at doses of 250 and 500 mg/kg BW respectively on day 8 post-inoculation. Various hematological parameters evaluated were not significantly altered(P0.05) at all doses of the extract, except red blood cell count which was signifi cantly elevated(P0.05) at 100 mg/kg BW. The extract significantly increased(P0.05) urea, creatinine, cholesterol, high-density lipoprotein-cholesterol and bilirubin concentrations in the serum as well as atherogenic index, while it reduced albumin concentration significantly(P0.05) at higher doses compared to the controls. Alanine aminotransferase activity was reduced in the liver and heart signifi cantly(P0.05) but was increased in the serum signifi cantly(P0.05) at higher doses of the extract compared to the controls.CONCLUSION: The results suggest that methanolic extract of the Dwarf red variety has partial antimalarial activity at higher doses, but is capable of impairing normal kidney and liver function as well as predisposing subjects to cardiovascular diseases.