Quantitative Application to a Polypill by the Development of Stability Indicating LC Method for the Simultaneous Estimation of Aspirin, Atorvastatin, Atenolol and Losartan Potassium

Polypill is a fixed-dose combination (FDC) containing three or more drugs in a single pill with the intention of reducing the number of tablets or capsules that need to be taken. Developing a single analytical method for the estimation of individual drugs in a Polypill is very challenging, due to the formation of drug-drug and drug-excipients interaction impurities. Here an attempt was made to develop a new, sensitive, single stability-indicating HPLC method for the simultaneous quantitative determination of Aspirin (ASP) Atorvastatin (ATV), Atenolol (ATL) and Losartan potassium (LST) in a polypill form in the presence of degradation products. Efficient chromatographic separation was achieved on a C18 stationary phase with simple mobile phase combination of buffer and Acetonitrile. Buffer consists of 0.1% Orthophosphoric acid (pH 2.9), delivered in a gradient mode and quantitation was carried out using ultraviolet detection at 230 nm with a flow rate of 1.0 mL/min. The retention times of Atenolol, Aspirin, Losartan potassium, and Atorvastatin were 3.3, 7.6, 10.7 and 12.9 min respectively. The combination drug product are exposed to thermal, acid/base hydrolytic, humidity and oxidative stress conditions, and the stressed samples were analyzed by proposed method. The method was validated with respect to linearity;the method was linear in the range of 37.5 to 150.0 μg/mL for ASP, 5.0 to 20.0 μg/mL for ATV and 25.0 to 100.0 μg/mL for ATL and LST. Acceptable precision and accuracy were obtained for concentrations over the standard curve ranges. The validated method was successfully applied to the analysis of Starpill tablets constituting all the four drugs;the percentage recoveries obtained were 99.60% for ASP, 99.30% for ATV, 99.41% for ATL and 99.62% for LST.

肾病大鼠肾脏诱生型一氧化氮合酶表达及Losartan的干预作用

目的:探讨肾小球硬化大鼠肾组织诱生型一氧化氮合酶(iNOS)基因及蛋白表达,以及losartan的影响及其意义。方法:单侧肾切除加阿霉素尾静脉注射制作肾小球硬化大鼠模型,随机分成假手术组(C组),肾小球硬化组(D组)和肾小球硬化losartan治疗组(DL组),每组10只。DL组灌胃losartan40mg/(kg·d),治疗6周后应用RT-PCR和WesternBlotting分别检测肾皮质iNOS、转化生长因子β1(TGFβ1)mRNA和蛋白表达,并分析肾脏病理改变,测定血白蛋白、胆固醇、尿素氮及肌酐,24h尿蛋白定量。结果:D组出现明显蛋白尿、低蛋白血症及高胆固醇血症,与C组比较差异有显著性(P<0.05),肾小球系膜细胞增生,细胞外基质沉积,与C组比较,肾皮质iNOSmRNA和蛋白表达上升3.28倍和2.15倍,TGFβ1mRNA和蛋白表达上升3.59倍和2.60倍。应用losartan治疗6周后,能明显减轻肾病生化改变及病理改变,与D组比较肾皮质iNOSmRNA和蛋白表达分别下调47%和58%,多组间方差分析差异有显著性意义(P<0.05)。结论:iNOS参与肾小球硬化过程,losartan减轻肾小球硬化早期肾脏损伤与抑制NO过度表达有关。

bFGF在压力超负荷肥厚心肌中的表达及Losartan干预的实验研究

目的:探讨碱性成纤维细胞生长因子(bFGF)在左室肥厚发生、发展中的作用及Losartan对左室肥厚的干预作用。方法:应用免疫组化法测定腹主动脉缩窄后大鼠心肌组织bFGF的表达变化。结果:腹主动脉缩窄后心肌组织bFCF在心肌细胞中的表达显著增加,P<0.01,术后第7d达最高峰;术后第14d左室肥厚病理改变明显。应用AngⅡ_1型受体(AT1)拮抗剂Losartan后,bFGF表达下降,左室肥厚被抑制。结论:bFGF参与左室肥厚的发生、发展,Losartan可抑制左室肥厚。

Losartan activates sirtuin 1 in rat reduced-size orthotopic liver transplantation

AIM: To investigate a possible association between losartan and sirtuin 1(SIRT1) in reduced-size orthotopic liver transplantation(ROLT) in rats.METHODS: Livers of male Sprague-Dawley rats(200-250 g) were preserved in University of Wisconsin preservation solution for 1 h at 4 ℃ prior to ROLT.In an additional group,an antagonist of angiotensin Ⅱ type 1 receptor(AT1R),losartan,was orally administered(5 mg/kg) 24 h and 1 h before the surgical procedure to both the donors and the recipients.Transaminase(as an indicator of liver injury),SIRT1 activity,and nicotinamide adenine dinucleotide(NAD+,a co-factor necessary for SIRT1 activity) levels were determined by biochemical methods.Protein expression of SIRT1,acetylated Fox O1(ac-Fox O1),NAMPT(the precursor of NAD+),heat shock proteins(HSP70,HO-1) expression,endoplasmic reticulum stress(GRP78,IRE1 a,p-e IF2) and apoptosis(caspase 12 and caspase 3) parameters were determined by Western blot.Possible alterations in protein expression of mitogen activated protein kinases(MAPK),such as p-p38 and p-ERK,were also evaluated.Furthermore,the SIRT3 protein expression and m RNA levels were examined.RESULTS: The present study demonstrated that losartan administration led to diminished liver injury when compared to ROLT group,as evidenced by the significant decreases in alanine aminotransferase(358.3 ± 133.44 vs 206 ± 33.61,P < 0.05) and aspartate aminotransferase levels(893.57 ± 397.69 vs 500.85 ± 118.07,P < 0.05).The lessened hepatic injury in case of losartan was associated with enhanced SIRT1 protein expression and activity(5.27 ± 0.32 vs 6.08 ± 0.30,P < 0.05).This was concomitant with increased levels of NAD+(0.87 ± 0.22 vs 1.195 ± 0.144,P < 0.05) the co-factor necessary for SIRT1 activity,as well as with decreases in ac-Fox O1 expression.Losartan treatment also provoked significant attenuation of endoplasmic reticulum stress parameters(GRP78,IRE1 a,p-e IF2) which was consistent with reduced levels of both caspase 12 and caspase 3.Furthermore,losartan administration stimulated HSP70 protein expression and attenuated HO-1 expression.However,no changes were observed in protein or m RNA expression of SIRT3.Finally,the protein expression pattern of p-ERK and p-p38 were not altered upon losartan administration.CONCLUSION: The present study reports that losartan induces SIRT1 expression and activity,and that it reduces hepatic injury in a ROLT model.

环孢菌素A致大鼠肾小管间质细胞凋亡及Losartan、Enalapril的保护作用

以低盐饮食 (钠含量 0 .0 5 % )饲养大鼠 7天后随机分成①对照组 ,②CsA处理组 ,③CsA +盐酸维拉帕米处理组 ,④CsA +Losartan处理组 ,⑤CsA +Enalapril处理组。CsA皮下注射剂量为 15mg/ (kg·d) ,连续 4周。用TUNEL法检测凋亡细胞 ,免疫组化方法观察增殖细胞核抗原 (PCNA)、Fas抗原表达。结果发现CsA处理后大鼠肾小管间质凋亡细胞较对照组明显增加 ,增殖细胞也有代偿性增加 ,肾小管上皮细胞Fas抗原表达增多。与CsA处理组相比 ,Losartan、Enalapril处理组肾小管间质细胞凋亡和Fas抗原表达明显减少。结果提示CsA可促进肾小管间质细胞凋亡 ,导致肾小管间质纤维化 ,Fas可能是介导肾小管细胞凋亡的重要介质。Losartan、Enalapril对CsA所致的肾小管间质细胞凋亡有保护作用。

血管紧张素Ⅱ受体阻滞剂Losartan的临床应用进展

血管紧张素Ⅱ(A—Ⅱ)受体阻滞剂Losartan是一种新型的肾素—血管紧张素系统(RAS)阻滞剂,从动物和人体研究显示其抗高血压安全有效,而且通常不引起血管紧张素转换酶抑制剂(ACEI)类副作用,作用优于ACEI。在复杂的RAS疾病的治疗中,Losartan呈现许多优点。本文简单介绍其在临床的应用。 高血压:显示抗高血压安全有效,在治疗动物正常与高血浆肾素活性(PRA)

Losartan对糖尿病肾病患者血肉皮素、一氧化氮及肾脏功能影响的探讨

目的：研究络沙坦（Ｌｏｓａｒｔａｎ）对糖尿病肾病内皮素（ＥＴ）、一氧化氮（ＮＯ）及肾功能的影响，探讨络沙坦对糖尿病肾病的防治机制及对肾脏的保护作用。方法：６１例糖尿病肾病患者，随机分为三组：对照组，单用降糖药；依那普利组（降糖药＋Ｅｎａｌａｐｒｉｌ １０ ｍｇ ｑｄ ｐｏ）；络沙坦组（降糖药＋络沙坦５０ ｍｇ ｑｄ ｐｏ）。用药时间８周。结果：络沙坦组与对照组相比， ＥＴ、ＮＯ、ＵＡＥ、ａ１－ＭＧ及Ｓｃｒ（肾功能不全期）治疗后８周均下降，有显著差异（Ｐ＜０．０５）；络沙坦组与Ｅｎａｌａｐｒｉｌ组相比无显著性差异（Ｐ＞０．０５）。结论：络沙坦与血管紧张素转换酶抑制剂（ＡＣＥＩ）同样具有保肾作用，由于ＡＣＥＩ的临床副反应较多，因此络沙坦在临床的应用前景优于ＡＣＥＩ。

Effects of Losartan on Cell Apoptosis and Expression of Caspase-3 and JNK Proteins in Kidney Tissue in Renal Interstitial Fibrosis Rats

[Objectives]To investigate the effects of losartan on cell apoptosis and the expression of caspase-3 and JNK proteins in kidney tissue in the adenine-induced renal fibrosis rats.[Methods]Thirty Wistar rats were randomly divided into three groups:control group(n=10),model group(n=10)and losartan group(n=10).The rats in the control group received saline,while those in the model group and losartan group both received adenine by gavage,for 21 d.After the renal interstitial fibrosis model was established,the rats in the losartan group were treated with losartan[10 mg/(kg·d)],while the rats in the control group and the model group rats were administered with the same amount of saline.The course of treatment was 30 d.Finally,the renal function,blood urea nitrogen(BUN),serum creatinine(Scr),creatinine clearance rate(Ccr)and the pathological morphology of the rats were detected.The apoptosis of renal tubular epithelial cells was tested by TUNEL.The caspase-3 and JNK protein expression was tested by Western blotting.[Results]After administering adenine for 21 d,the BUN,24 MTP and kidney/body weight in the model group were increased,significantly higher than the control group(P<0.01),and the Ccr was remarkably decreased(P<0.01),signifying that the renal interstitial fibrosis model was successfully built.After treating with losartan for 30 d,the Scr,BUN,and 24 MTP were significantly decreased(P<0.01),and the Ccr was significantly increased in the losartan group(P<0.01).In addition,in comparison to the model group,renal tubular epithelial apoptosis was decreased and caspase-3 and JNK expression was downregulated in the losartan group(P<0.05).[Conclusions]Losartan can reduce the adenine-induced elevation of Scr,BUN and 24 hMPT,increase Ccr,improve general condition of renal interstitial fibrosis in rats and ameliorate the progression of chronic kidney failure(CKD).The effectiveness of losartan is probably due to its ability to regulate caspase-3,JNK protein expression and attenuate renal cell apoptosis.

Effect of leflunomide combined with losartan potassium therapy on renal function and glomerular podocyte injury in patients with diabetic nephropathy

Objective:To study the effect of leflunomide combined with losartan potassium therapy on renal function and glomerular podocyte injury in patients with diabetic nephropathy.Methods:A total of 82 patients with diabetic nephropathy (CKDIIIa, IIIb stage) who were treated in our hospital between June 2013 and May 2016 were selected as the research subjects, random number table was used to divide them into leflunomide (LEF) group and control group who received leflunomide combined with losartan potassium therapy and losartan potassium monotherapy respectively. Before treatment and 8 weeks after treatment, serum contents of renal function indexes, RAAS molecules and inflammatory factors as well as urine contents of podocyte damage proteins were determined.Results:8 weeks after treatment, serum Scr, BUN, CysC, PRA, AT-II, ALD, IL-1β, IL-6 and TNF-α contents, urine ACR levels as well as podocalyxin, nephrin, CA2AP and podocin contents of both groups of patients were significantly lower than those before treatment, and serum Scr, BUN, CysC, IL-1β, IL-6 and TNF-α contents, urine ACR level as well as podocalyxin, nephrin, CA2AP and podocin contents of LEF group were significantly lower than those of control group, serum PRA, AT-II, ALD contents had no significant difference with control group.Conclusion:Leflunomide combined with losartan potassium therapy can improve the renal function of patients with diabetic nephropathy, and inhibit the inflammatory response injury to glomerular podocyte.

Losartan降压效应及对高血压病患者血浆肾素、血管紧张素Ⅱ、醛固酮水平的影响

目的 探讨 Ang 受体拮抗剂 L osartan对 EH患者的降压效应及血浆 RAAS的影响。方法 1～ 3级高血压病患者 6 5例 ,给予 L osartan 5 0 mg/d治疗 8周 ,分别于治疗前、后测量患者血压、心率。并分别于治疗前、1周、8周时用放射免疫法测定血浆 PRA、Ang 、 Ald活性。结果 1L osartan对 1～ 3级高血压患者 SBP、DBP均有下降作用 ,降压同时心率不增快。 2 L osartan治疗 1周时血浆 PRA、Ang 显著高于治疗前 (P<0 .0 5或 P<0 .0 1)。 Ald则较治疗前降低 (P<0 .0 5 )。 8周时 PRA、Ang 仅轻度升高与治疗前相比差异无显著性 (P>0 .0 5 ) ,Ald则较 1周时有进一步下降 ,但无显著性 (P>0 .0 5 )。结论 1L osartan 5 0 mg/d能有效降低不同程度的 SBP、DBP,降压同时心率无反射性增加。 2长期服用 L osartan不会引起血浆 PRA、Ang 持久异常增高 ,而

Losartan和人参对实验性大鼠心肌缺血再灌注心肌细胞凋亡影响的比较研究

目的 研究Losartan和人参对缺血再灌注心肌细胞凋亡的影响 ,比较Losartan和人参对缺血再灌注心肌细胞损伤的保护作用。方法 结扎Wistar大鼠左冠状动脉前降支 ,建立大鼠缺血再灌注动物模型 ,采用末端标记原位细胞凋亡法检测心肌细胞凋亡 ,并利用光学显微镜进行细胞计数。结果 单纯缺血 再灌注组心肌细胞凋亡数较假手术组明显增多(37 5± 9 2 2 /视野vs 0 18± 0 0 91/视野 ,P <0 0 5 ) ,Losartan组和人参组心肌细胞凋亡数分别为 6 5 0± 3 5 9/视野和 8 74± 3 5 1/视野 ,较单纯缺血 再灌注组明显减少 (P <0 0 5 ) ,Losartan和人参两组间无明显区别 (P >0 0 5 )。结论 缺血再灌注可引起明显的心肌细胞凋亡 ,Losartan和人参对缺血再灌注心肌损伤具有相似的保护作用 ,均可明显减少缺血再灌注心肌细胞凋亡。

Losartan对神经肽Y诱导血管平滑肌细胞增殖的逆转作用

目的 :观察神经肽Y(NPY)与血管紧张素受体拮抗剂losartan对体外培养的血管平滑肌细胞(VSMC)中PCNA、PDGF、c -myc癌基因表达的影响 ,从分子生物学的角度探讨NPY在高血压、动脉粥样硬化发生中的作用和losartan的逆转作用。方法 :应用荧光免疫组化定量技术 (ACAS5 70共聚焦激光扫描显微细胞仪 )。结果 :NPY刺激VSMC增殖 ,使其PCNA、PDGF和c -myc癌基因的表达明显高于对照组 ;losartan则可逆转NPY对VSMC增殖的刺激作用 ,使PCNA、PDGF和c -myc癌基因表达的平均荧光值降低。结论 :NPY促进VSMC的增殖 ,其作用与高血压的发生有关 ;而losartan对高血压的治疗作用可能与拮抗NPY对VSMC增殖的刺激作用有关。

UPLCMS Method Development and Validation of Amlodipine, Hydrochlorthiazide and Losartan in Combined Tablet Dosage Form

A simple, rapid, sensitive and specific UPLCMS method was developed and validated following ICH guidelines for simultaneous estimation of tablet dosage form containing amlodipine (AMLO) hydrochlorothiazide (HCT) and losartan (LOSAT) using telmisartan (TELMI) as an internal standard (IS). The separation was achieved using Waters ACQUITY BEH C18 (1.7 μm, 2.1 × 50 mm) column with gradient mode, mobile phase containing acetonitrile (A) & 1% ammonium acetate (B) pH adjusted to 2.8 with trifluoro acetic acid with gradient mode. The flow rate was 0.4 mL·mL﹣1 and the injection volume 2 μl. The retention time for amlodipine, hydrochlorothiazide and losartan was found to be 3.7, 2.5 and 3.9 min, respectively. The developed method was found to be linear over the concentration range of 50 - 300 ng·mL﹣1, 125 - 750 ng·mL﹣1 and 500 - 3000 ng·mL﹣1 for AMLO, HCT and LOSAT respectively. The signal intensities obtained in ion mode for amlodipine, hydrochlorothiazide, losartan and telmisartan (IS) they were found to be much higher positive ion mode (M+)﹣ parent ion at m/z, 409.02, 297.97, 422.91 and 515.03, respectively, in QUATTROZQ full scan mass spectra.

Effects of six months losartan administration on liver fibrosis in chronic hepatitis C patients: A pilot study

AIM： TO evaluate the safety and efficacy of chronic administration of Iosartan on hepatic fibrosis in chronic hepatitis C patients.METHODS： Fourteen patients with chronic hepatitis C non-responders （n = 10）, with contraindications （n = 2） or lack of compliance （n = 2） to interferon plus ribavirin therapy and liver fibrosis were enrolled. Liver and renal function test, clinical evaluation, and liver biopsies were performed at baseline and after Iosartan administration at a dose of 50 mg/d during the 6 mo. The control group composed of nine patients with the same inclusion criteria and paired liver biopsies （interval 6-14 mo）. Histological activity index （HAI） with fibrosis stage was assessed under blind conditions by means of Ishak＇s score. Subendothelial fibrosis was evaluated by digital image analyses.RESULTS： The changes in the fibrosis stage were significantly different between Iosartan group （decrease of 0.5±1.3） and controls （increase of 0.89±1.27; P〈0.03）. In the treated patients, a decrease in fibrosis stage was observed in 7/14 patients vs 1/9 control patients （P〈0.04）. A decrease in sub-endothelial fibrosis was observed in the Iosartan group. No differences were found in HAI after Iosartan administration. Acute and chronic decreases in systolic arterial pressures （P〈0.05） were observed after the Iosartan administration, without changes in mean arterial pressure or renal function.CONCLUSION： Chronic AT-Ⅱ type 1 receptor （AT1R） blockade may reduce liver fibrosis in patients with chronic hepatitis C.

Losartan和CGRP对血管紧张素Ⅱ诱导血管平滑肌细胞增殖作用的影响

目的比较非肽类血管紧张素Ⅱ受体Ⅰ型阻断剂氯沙坦(Losartan)和血管活性肽降钙素基因相关肽(CGRP)对血管紧张素Ⅱ诱导的血管平滑肌细胞增殖作用的影响,为探讨此两类物质的降压机制提供实验依据。方法采用MTT,3H-参入法和流式细胞仪分别测定血管紧张素Ⅱ刺激下,Losartan或CGRP干预下血管平滑肌细胞的增殖变化,W est-ern b loting法测定不同状态下血管平滑肌细胞内ERK1/2的活性变化。结果Losartan或CGRP能抑制血管紧张素Ⅱ刺激下血管平滑肌细胞的生存率、DNA合成、细胞周期增殖指数,以及细胞内ERK1/2的活性,并呈剂量依赖性。而且,CGRP抑制作用强于Losartan。结论Losartan或CGRP能抑制血管紧张素Ⅱ刺激下血管平滑肌细胞增殖,其细胞内的信号传导途径与ERK1/2有关。

Losartan(科素亚)和卡托普利治疗高血压病的对照研究

目的：评价科素亚同卡托普利治疗高血压病的疗效及其对血脂、肾功能及副作用的影响。方法：５９ 例原发性高血压患者给予Ｌｏｓａｒｔａｎ（科素亚）剂量５０～１００ｍ ｇ／天，治疗六周，对照组５６ 例服用卡托普利，剂量２５ｍ ｇ／次，每天２～３次。治疗前后所有参与者测血压和测定胆固醇、甘油三酯、肾功能。结果：监测血压显示Ｌｏｓａｒｔａｎ 组降压与卡托普利对照组无差异，对胆固醇、甘油三酯没有影响，有降低尿酸的作用，与卡托普利对照组相比，咳嗽发生率低，并能改善肾功能及保护内皮细胞功能。结论：科素亚同卡托普利治疗轻、中度高血压病安全、有效，对血脂、肾功能无影响。科素亚有降低尿酸的作用。

Pharmacokinetics of Hydrochlorothiazide, Losartan and E3174 after Oral Doses of Losartan and Losartan/Hydrochlorothiazide in Healthy Chinese Male Volunteers

Aims: A simple and highly sensitive LC-MS method was used to determine the concentrations of losartan, its major active metabolite E3174 and hydrochlorothiazide in human plasma and pharmacokinetic characteristics and metabolism phenotype observation after administration of losartan tablets and losartan/hydrochlorothiazide combination tablets. Methods: An open, randomized cross-over single-dose study was designed in forty healthy male volunteers, A single-dose of 50 mg losartan tablets or 50 mg losartan/12.5 mg hydrochlorothiazide combination tablets was orally given and blood samples were collected at scheduled time. A LC-MS method was established and evaluated for determining the plasma concentrations of losartan, E3174 and hydrochlorothiazide. The pharmacokinetic parameters and characteristic of metabolism phenotypes were calculated and compared via this test. Results: The elimination rate of E3174 (t1/2) was significantly shorter (P 0–t was lower (P 1/2, AUC0–t and AUC0–inf of E3174.

神经肽Y刺激血管平滑肌增殖和losartan的干预作用

目的 :探讨神经肽Y和肾素 -血管紧张素系统之间的相互作用与高血压疾病发生之间的关系。方法 :应用快速微量MTT比色法和荧光免疫组化定量技术 ,观察神经肽Y对体外培养血管平滑肌细胞增殖活度和血管平滑肌细胞核细胞增殖抗原表达的影响以及血管紧张素Ⅱ受体拮抗剂losartan对其影响的干预作用。结果 :神经肽Y可刺激体外培养血管平滑肌细胞的增殖、使其增殖活度 (MTT -OD值 )和细胞内核增殖抗原(PCNA)的表达明显高于对照组 (P <0 0 1)。而losartan则可降低神经肽Y对血管平滑肌细胞增殖活度 (MTT -OD值 )的刺激作用 ,减少细胞内核增殖抗原 (PCNA)的表达。结论 :神经肽Y可促进体外培养的血管平滑肌细胞的增殖 。