槲皮素对大鼠心肌缺血再灌注损伤的保护作用

摘 要 目的： 探讨槲皮素（QU）对心肌缺血再灌注（MI/R）损伤的保护及炎症反应的影响。方法: 采用结扎左冠脉前降支30 min再灌注2 h的方法复制MI/R损伤大鼠模型,随机分为QU组（25,50,100 mg·kg^-1）、模型组、假手术组（n=10）,各组于术前1周开始灌胃给药,qd。再灌注结束后取血清,采用比色法测定肌酸激酶（CK）和乳酸脱氢酶（LDH）活性,ELISA法测定肿瘤坏死因子-α（TNF-α）和白细胞介素-1β（IL-1β）水平;取心脏,染色法测定心肌梗死面积;取心肌匀浆,测定髓过氧化物酶（MPO）活力。结果: QU高、中剂量可分别缩小MI/R损伤大鼠心肌梗死面积至25.00%、25.31%,与模型组（32.55%）比较差异有统计学意义（P<0.05）;与模型组CK活性（1 123.78 U·L^-1）比较,QU各剂量可分别降低血清CK活性为779.82、793.90、870.86U·L^-1（P＜0.01）;与模型组LDH活性（3 105.32 U·L^-1）比较,QU各剂量可分别降低血清LDH活性为2 138.21、2 277.40、2 416.53U·L^-1（P <0.05或P＜0.01）;QU各剂量组心肌MPO活力分别为185.70,190.66,210.03 U·g^-1,与模型组（311.72U·g^-1）比较差异均有统计学意义（P<0.05或P＜0.01）;与模型组TNF-α水平（119.55pg·ml^-1）比较,QU高、中剂量组血清TNF-α水平分别降低至97.48、97.54pg·ml^-1（P<0.05）;与模型组IL-1β水平（673.34pg·ml^-1）比较,QU各剂量分别降低血清IL-1β水平至419.26、438.72、492.53pg·ml^-1（P＜0.01）。结论:QU预处理可保护MI/R所致心肌损伤,其机制与抑制中性粒细胞浸润、减少炎性细胞因子的释放等有关。     

松果菊苷调控Sirt1 FOXO1通路减轻大鼠心肌缺血再灌注损伤

摘 要 目的：研究松果菊苷通过调控沉默信息转录调节因子1（Sirt1） 叉形头转录因子1（FOXO1）通路减轻大鼠心肌缺血再灌注（MI/R）损伤。 方法: 结扎大鼠左冠状动脉前降支30 min,再灌注6 h建立MI/R损伤模型。将大鼠随机分为4组：假手术组、MI/R组、松果菊苷+MI/R组、Sirt1特异性抑制剂EX527+松果菊苷+MI/R组,每组10只,腹腔注射给药。心脏切片后用三苯基氯化四氮唑（TCC）染色测定心肌梗死面积;分光光度法测定血清中乳酸脱氢酶（LDH）和肌酸激酶（CK）含量;TUNEL法检测心肌细胞凋亡率;蛋白质印迹法（Western blot）和逆转录聚合酶链反应（RT PCR）检测sirt1和FOXO1蛋白和mRNA表达水平。 结果: 与MI/R组比较,松果菊苷+MI/R组大鼠心肌梗死面积、LDH和CK含量、心肌细胞凋亡率、FOXO1蛋白和mRNA表达水平显著降低,Sirt1蛋白和mRNA表达水平显著升高（P＜0.05）。与松果菊苷+MI/R组比较,EX527+松果菊苷+MI/R组大鼠心肌梗死面积、LDH和CK含量、心肌细胞凋亡率、FOXO1蛋白和mRNA表达水平显著升高,而Sirt1蛋白和mRNA表达水平显著降低（P＜0.05）。 结论: 松果菊苷能够减轻大鼠心肌缺血再灌注损伤,其机制可能与调控Sirt1 FOXO1通路有关。     

甘青铁线莲皂苷对大鼠心肌缺血/再灌注损伤的保护作用

摘 要 目的：研究甘青铁线莲皂苷（CTS）对大鼠心肌缺血/再灌注（MI/R）损伤的影响。 方法: 可逆性冠脉左前降支结扎缺血30 min 再灌注3 h 复制MI/R 模型,将SD大鼠随机分为假手术组、模型组、CTS低、中、高剂量组(50,100,200 mg·kg-1),每组10 只。采用伊文思蓝（EB）、2,3,5 氯化三苯基四氮唑蓝（TTC）双染法测定心肌梗死面积,苏木精 伊红（HE）染色法观察心肌病理学形态变化,并检测血清中乳酸脱氢酶（LDH）、肌酸激酶同工酶（CK MB）、肿瘤坏死因子 α (TNF α)、白细胞介素 6 (IL 6)、超氧化物歧化酶（SOD）及丙二醛（MDA）水平。 结果: 与模型组比较,中、高剂量的CTS可明显缩小心肌梗死面积,并显著降低血清中LDH、CK MB、TNF α、IL 6及 MDA的水平,显著增加血清中SOD的活性（P<0.05或P<0.01）,且CTS各剂量组心肌组织的病理损伤也低于模型组。 结论: CTS对大鼠MI/R 损伤具有保护作用,其机制可能与其抑制炎症因子的释放和调节氧化应激有关。     

芒果苷对大鼠心肌缺血再灌注损伤的保护作用及其机制研究

目的 探讨芒果苷(MGF)预处理对大鼠心肌缺血再灌注(MI/R)损伤的保护作用及机制。方法 SD大鼠随机分为5组,即假手术组、模型组和MGF高、中、低剂量(40、20、10 mg/kg)组,采用结扎左冠脉前降支30 min再灌注2 h的方法制备大鼠MI/R损伤模型,于术前7 d开始ig给药。采用比色法测定血清肌酸激酶(CK)和乳酸脱氢酶(LDH)活性,ELISA法测定血清肿瘤坏死因子-α(TNF-α)和白细胞介素-1β(IL-1β)水平;染色法测定心肌梗死面积(MIS);取心肌匀浆,比色法测定髓过氧化物酶(MPO)活性。结果 与模型组比较,MGF高、中剂量组MIS、血清LDH活性显著降低(P<0.05);MGF各剂量组血清CK活性、血清TNF-α和IL-1β水平、心肌MPO活性明显降低(P<0.05、0.01)。结论 MGF预处理通过抑制中性粒细胞浸润,下调TNF-α和IL-1β表达,抑制炎症反应,发挥对MI/R所致心肌损伤的保护作用。     

丹酚酸B预处理对心肌缺血/再灌注损伤能量代谢的影响

目的 观察丹酚酸B预处理对大鼠心肌缺血/再灌注损伤（MI/RI）能量代谢的作用。方法 通过结扎冠状动脉30min再灌注2 h建立大鼠MI/RI模型,随机分为4组：假手术组、模型组及丹酚酸B高、低（20、10 mg/kg）组,于建立模型前7 d开始ip给药,每天1次;再灌注结束后,采用比色法测定血清乳酸脱氢酶（LDH）、肌酸激酶（CK）活力,染色法测定心肌梗死面积（MIA）,定磷法测定心肌组织Na⁺-K⁺-ATP酶、Ca²⁺-Mg²⁺-ATP酶活性。结果 与模型组（42.60%）比较,丹酚酸B高、低剂量组的MIA分别缩小至35.93%和37.21%,差异显著（P<0.05）;与模型组比较,丹酚酸B高、低剂量组血清CK、LDH活力均显著降低（P<0.05、0.01）;与模型组比较,丹酚酸B高、低剂量组心肌组织Na⁺-K⁺-ATP酶、Ca²⁺-Mg²⁺-ATP酶活性均显著升高（P<0.05、0.01）。结论 丹酚酸B预处理可保护MI/RI所致心肌损伤,作用途径可能与改善心肌组织的能量代谢相关。     

木棉花总黄酮对大鼠心肌缺血再灌注损伤的保护作用

目的 研究木棉花总黄酮对大鼠心肌缺血再灌注损伤的保护作用，并探讨其作用机制。方法 将健康SD大鼠随机分为假手术组、模型组、阳性对照组（复方丹参滴丸135 mg·kg^-1），木棉花总黄酮低、中、高剂量组（100，200，400 mg·kg^-1）。每日灌胃给药1次，连续给药7 d，假手术组与模型组每天灌服等体积的生理盐水，采用冠状动脉左前降支结扎法建立心肌缺血再灌注损伤模型，检测大鼠血清肌酸激酶同工酶（CK-MB）、肌酸激酶（CK）、乳酸脱氢酶（LDH）、乳酸脱氢酶同功酶1（LDH-1）、超氧化物歧化酶（SOD）、还原型谷胱甘肽（GSH）、谷胱甘肽过氧化物酶（GSH-Px）、丙二醛（MDA）、一氧化氮（NO）和一氧化氮合酶（NOS）的变化。TTC法测量心肌梗死面积，并观察心肌组织病理学变化。结果 与假手术组比较，模型组大鼠血清中CK-MB、CK、LDH、LDH-1、MDA的含量显著升高，SOD、GSH、GSH-Px、NO和NOS的活性显著降低，心肌组织严重梗死和坏死；与模型组比较，木棉花总黄酮各剂量组能明显降低大鼠血清中CK-MB、CK、LDH、LDH-1、MDA的含量，提高SOD、GSH、GSH-Px、NO和NOS的活性，同时可减少心肌梗死面积，减轻心肌细胞肿胀和炎性细胞浸润，改善缺血心肌的病理变化。结论 木棉花总黄酮对大鼠心肌缺血再灌注损伤有明显保护作用，其机制可能与减少氧自由基的产生，调节氧化与抗氧化平衡有关。     

黄柏提取物对大鼠心肌损伤的保护作用

摘 要 目的：探讨黄柏水提物和醇提物对垂体后叶素和盐酸异丙肾上腺素致大鼠心肌损伤的保护作用及其可能的作用机制。方法: 将SD大鼠随机分为正常对照组、模型组、复方丹参片组、黄柏水提组、黄柏醇提组,建立垂体后叶素和盐酸异丙肾上腺素大鼠心肌损伤模型,检测血清中肌酸激酶（CK）、乳酸脱氢酶（LDH） 活性、心肌组织超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量。 结果: 与正常对照组比较,垂体后叶素建立的大鼠心肌损伤模型组血清LDH活性、CK活性和心肌组织MDA含量明显升高,心肌组织SOD活性明显降低（P<0.01）;盐酸异丙肾上腺素建立的大鼠心肌损伤模型组心肌组织MDA含量明显升高,心肌组织SOD活性明显降低（P<0.01）。与垂体后叶素建立的大鼠心肌损伤模型组相比较,各给药组血清LDH活性、CK活性和心肌组织MDA含量明显降低,心肌组织SOD活性明显升高,差异有统计学意义（P<0.05或P<0.01）;与盐酸异丙肾上腺素建立的大鼠心肌损伤模型组相比较,各给药组心肌组织中MDA含量明显降低,SOD活性明显升高,差异有统计学意义（P<0.05或P<0.01）。结论:黄柏提取液对垂体后叶素和盐酸异丙肾上腺素引起的大鼠心肌损伤有一定保护作用。     

尿激酶原对心肌缺血再灌注损伤大鼠心功能及血清心肌酶活性的影响

目的 探讨尿激酶原（Pro-UK）对心肌缺血再灌注（MI/R）损伤大鼠心功能及血清心肌酶活性的影响及其机制。方法 将大鼠随机分为假手术组、MI/R模型组和Pro-UK低、中、高剂量（0.5、1.0、2.0 mg/kg）组,Pro-UK低、中、高剂量（0.5、1.0、2.0 mg/kg）组大鼠分别于造模前给药,前3 d每天尾iv 0.5、1.0、2.0 mg/kg Pro-UK,后2 d每天尾iv给予0.25 mg/kg Pro-UK,假手术组、模型组尾iv给予等量生理盐水,预处理完成后均采用手术结扎的方式复制大鼠MI/R模型,其中假手术组不进行结扎操作,再灌注150 min后测量心率,摘眼球取血后处死大鼠,取左心室,伊文思蓝-TTC法检测心肌梗死面积,HE染色观察心肌组织病理情况,TUNEL法检测心肌细胞凋亡情况,试剂盒检测血清肌酸激酶（CK）、肌酸激酶同工酶（CK-MB）、乳酸脱氢酶（LDH）、纤溶酶原激活剂抑制剂1（PAI-1）和组织纤维溶酶原激活物（t-PA）水平,Western blotting检测心肌组织中线粒体凋亡关键蛋白以及核因子κB（NF-κB）-p65蛋白磷酸化水平。结果 Pro-UK预处理能够明显降低MI/R大鼠心肌梗死面积、CK、CK-MB、LDH、PAI-1水平、升高t-PA水平,加快心率,能够改善心肌病理损伤,降低心肌细胞凋亡率,同时抑制Caspase-3、p-p65、Bax蛋白表达,促进Bcl-2蛋白表达。结论 Pro-UK预处理能够改善MI/R损伤大鼠心功能并抑制血清心肌酶活性,其作用机制可能与NF-κB信号有关。     

积雪草苷对大鼠心肌缺血再灌注损伤的保护作用研究

目的 研究积雪草苷(AC)对在体大鼠心肌缺血再灌注损伤的保护作用, 初步探讨其机制。方法 40只SPF级Wistar大鼠, 随机分为假手术组、心肌缺血再灌注模型组及积雪草苷低、中、高剂量组, 每组8只。积雪草苷低、中、高剂量组分别以2.5、5.0、10.0 mL/kg体质量的剂量连续ig药液14 d, 药液质量浓度1.5 mg/mL。其他各组同时点ig 0.5%羧甲基纤维素钠溶液。除假手术组外, 其他各组结扎左冠状动脉前降支, 使心肌缺血30 min, 再灌注60 min。用7020全自动生化分析仪检测血清中超氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)、肌酸激酶同工酶(CK-MB)活性和丙二醛(MDA)水平;ELISA法测定血清中C反应蛋白(CRP);TUNEL法检测各组大鼠缺血心肌细胞凋亡;RT-PCR法检测B细胞白血病/淋巴瘤-2基因(Bcl-2)和与Bcl-2相关的x蛋白(Bax)的mRNA表达。结果 与模型组比较, 积雪草苷各剂量组均能降低血清中LDH、CK-MB活性及MDA的量(P<0.05), 升高血清中SOD活性(P<0.05);降低血清中CRP水平(P<0.05);降低心肌细胞凋亡指数(P<0.05);积雪草苷各组凋亡基因Bcl-2表达水平上升(P<0.05), Bax表达水平下降(P<0.05), Bcl-2/Bax比值升高(P<0.05)。结论 积雪草苷预处理能通过减少心肌细胞凋亡、抗脂质过氧化物产生及抗炎症反应等机制, 对心肌缺血再灌注损伤产生保护作用。     

nNOS抑制剂亚胺基烯丁基-L-鸟氨酸对心肌缺血再灌注损伤的影响及机制

目的 探讨nNOS选择性抑制剂亚胺基烯丁基-L-鸟氨酸（L-VNIO）对心肌缺血再灌注（I/R）损伤的影响及机制。方法 构建SD大鼠离体心脏I/R模型和H9c2细胞缺氧/复氧（H/R）模型；nNOS抑制剂L-VNIO（10 μmol·L^-1）持续给药整个再灌注或复氧过程。TTC染色测定心肌梗死面积；流式细胞术检测H9c2细胞凋亡率；Fluo-3/AM Ca²⁺荧光探针通过流式细胞仪检测H9c2细胞内Ca²⁺浓度；试剂盒法测定离体心脏灌流液乳酸脱氢酶（LDH）、丙二醛（MDA）水平以及H9c2细胞MDA水平和超氧化物歧化酶（SOD）活性；离体心脏提取肌浆网，试剂盒法检测肌浆网Ca²⁺-ATP酶（SERCA）活性，Western blotting检测肌浆网SERCA蛋白表达；Western blotting检测离体心脏中受磷蛋白（PLB）和兰尼碱受体2（RyR2）蛋白表达水平和磷酸化水平。结果 与I/R或H/R模型组相比，L-VNIO显著降低细胞凋亡率，减少心肌梗死面积，降低LDH、MDA水平，提高SOD活性，差异均有统计学意义（P<0.05）；此外，与I/R或H/R模型组相比，L-VNIO组明显降低细胞内Ca²⁺超载，增高PLB磷酸化水平，降低RyR2磷酸化水平，增强SERCA活性（P<0.05）。结论 nNOS抑制剂L-VNIO可以减轻I/R损伤，机制与调节Ca²⁺转运相关蛋白而降低I/R引起的Ca²⁺超载相关。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

---

Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.