大蒜素协同抗癌药对肿瘤细胞杀伤作用的研究

目的:探讨大蒜素对人胃癌细胞系MGC-803和SGC-7901细胞周期的影响及其与周期特异性药物联合使用,增强抗癌药物对肿瘤细胞的杀伤作用.方法:苔盼蓝拒染法检测细胞增殖抑制率以观察大蒜素对胃癌细胞的增殖抑制作用;流式细胞仪及瑞士-姬姆萨染色光镜观察检测细胞周期的改变;3μg/ml大蒜素与周期特异性抗癌药物博莱霉素A5和长春新碱联合使用,观察药物细胞毒活性的改变.结果:大蒜素可抑制MGC-803细胞生长,24h IC50为6.4μg/ml,也可抑制SGC-7901细胞的生长,24h IC50为7.3μg/ml;以3μg/ml、6μg/ml、9μg/ml终浓度大蒜素分别作用两种胃癌细胞系24h后,与对照组比较,G0/G1细胞周期百分率明显减少,而G2/M期明显增加(P＜0.01);6μg/ml大蒜素作用培养细胞24h后,与对照组比较细胞分裂指数明显增加.提示两种细胞系经大蒜素处理后,细胞周期阻滞于M期;大蒜素与两种抗癌药物联合使用,作用于MGC-803细胞,BLM A5和VCR的24h IC50值分别由单独应用的1.210μg/ml和0.125μg/ml下降到0.370μg/ml和0.031μg/ml,作用于SGC-7901细胞,BLM A5和VCR的24h IC50值分别由单独应用的1.760μg/ml和0.287μg/ml下降到0.680μg/ml和0.074μg/ml,显示低剂量大蒜素增强了抗癌药物对肿瘤细胞的杀伤作用.结论:大蒜素可使MGC-803及SGC-7901两种细胞周期阻滞于M期;大蒜素与M期特异作用抗癌药物联合使用,具有协同抗肿瘤作用.     

The effect of allicin on the ventricular myocytes of rabbit with heart failure北大核心CSCD

Objective To observe the effect of allicin on the action potential duration (APD) and L-type calcium current (ICa, L) in the ventricular myocytes of rabbits with heart failure in order to explore the mechanisms of therapeutic effect of allicin on cardiac arrhythmias complicated with heart failure. Methods Forty-five New Zealand White male rabbits were randomly (random number) assigned to 3 groups (n=15 in each group): sham operated group (sham group), heart failure group (HF group), and heart failure treated with allicin group (HF+AU group). The rabbit heart failure model was established by abdominal aortic constriction coupled with aortic regurgitation, the ventricular myocytes were obtained by enzyme double digestion, and the whole cell clamp was used to record action potential and calcium current.The action potential duration (APD), ICa, L and gating mechanism were observed during heart failure and allicin administered. Data were processed with pCLAMP version 10.2. Statistical analysis was performed using SPSS 17.0. Comparisons among groups were carried out using ANOVA, and SNK-g was used for multiple comparison as post-hoc. Results (1) Prolonged APD was found during heart failure, APD50 was prolonged from (93.4±4.7) ms in sham group to (115.5±6.2) ms in HF group (P<0.01). After administration of allicin 30 umol/L, APD50 was shortened to (105.2±5.5) ms (P<0.05). (2) The density of ICa, L increased during heart failure, peak current density increased increased from (-8.4±0.6) pA/pF in sham group to (-15.1±1.1) pA/pF while 0 mV attained at depolarizations (P<0.01). After administration of allicin 30 μmol/L, the current density reduced to (-10.1±0.8) pA/pF (P<0.01). The effect of allicin presented in both voltage dependent and consentration dependent manner. (3) According to the gating mechanism study, the main mechanism of lowering the density of ICa, L by allicin after heart failure was the acceleration of the steady inactivation of the channel, and the de-escalation of the recovery kinetic after the inactivation of the channel. Conclusions Allcin can be used to reduce the calcium current of ventricular myocytes in animal heart failure model, it has the potential of clinical use in treating cardiac arrhythmias during heart failure. © 2018 Chinese Medical Association. All rights reserved.     

大蒜素治疗幽门螺旋杆菌阴性慢性萎缩性胃炎的疗效评价

目的：探讨大蒜素对幽门螺杆菌（HP）阴性慢性萎缩性胃炎的治疗作用。方法采用前瞻性、自身对照方法,选择2010年1月至2012年6月于本院经胃镜加病理确诊的慢性萎缩性胃炎并HP阴性患者,共69例,所有患者常规服用大蒜素24周。对治疗前、治疗12、24周分别进行临床症状评分,治疗前、治疗24周分别行胃镜检查并取标本行组织病理检查,比较治疗前后的变化。结果治疗12、24周患者较治疗前临床症状评分下降,差异均具有统计学意义（P均＜0.05）;治疗24周后较治疗前内镜下表现、组织病理评分均有明显改善,差异具有统计学意义（P均＜0.05）。结论大蒜素可显著改善HP阴性慢性萎缩性胃炎患者的临床症状、内镜下表现及组织病理情况,值得临床进一步研究。     

Mechanisms underlying the antihypertensive effects of garlic bioactives

Cardiovascular disease remains the leading cause of death worldwide with hypertension being a major contributing factor to cardiovascular disease–associated mortality. On a population level, non-pharmacological approaches, such as alternative/complementary medicine, including phytochemicals, have the potential to ameliorate cardiovascular risk factors, including high blood pressure. Several epidemiological studies suggest an antihypertensive effect of garlic (Allium sativum) and of many its bioactive components. The aim of this review is to present an in-depth discussion regarding the molecular, biochemical and cellular rationale underlying the antihypertensive properties of garlic and its bioactive constituents with a primary focus on S-allyl cysteine and allicin. Key studies, largely from PubMed, were selected and screened to develop a comprehensive understanding of the specific role of garlic and its bioactive constituents in the management of hypertension. We also reviewed recent advances focusing on the role of garlic bioactives, S-allyl cysteine and allicin, in modulating various parameters implicated in the pathogenesis of hypertension. These parameters include oxidative stress, nitric oxide bioavailability, hydrogen sulfide production, angiotensin converting enzyme activity, expression of nuclear factor–κB and the proliferation of vascular smooth muscle cells. This review suggests that garlic and garlic derived bioactives have significant medicinal properties with the potential for ameliorating hypertension and associated morbidity; however, further clinical and epidemiological studies are required to determine completely the specific physiological and biochemical mechanisms involved in disease prevention and management.     

Allicin protects rat cardiomyoblasts (H9c2 cells) from hydrogen peroxide-induced oxidative injury through inhibiting the generation of intracellular reactive oxygen species

Oxidative stress is considered an important factor that promotes cell death in response to a variety of pathophysiological conditions. This study investigated the antioxidant properties of allicin, the principle ingredient of garlic, on preventing oxidative stress-induced injury. The antioxidant capacities of allicin were measured by using 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and hydrogen peroxide (H₂O₂)-induced cell damage on H9c2 cardiomyoblasts. Allicin (0.3–10?μM) pre-incubation could concentration-dependently attenuate the intracellular reactive oxygen species (ROS) increase induced by H₂O₂ on H9c2 cells. It could also protect H9c2 cells against H₂O₂-induced cell damage. However, the DPPH free radical scavenging activity of allicin was shown to be low. Therefore, it is believed that the protective effect of allicin on H9c2 cells could inhibit intracellular ROS production instead of scavenging extracellular H₂O₂ or free radicals. For the observed protective effect on H9c2 cells, allicin might also be effective in reducing free radical-induced myocardial cell death in ischemic condition.     

Study on the Inhibitory Effect of Allicin on Human Gastric Cancer Cell Line SGC-7901 and Its Mechanism

Background

Allicin is the main active constituent of Allium sativum L., which is characterized by broad antibacterial spectrum (MarkosN et al., 2008; Chen et al., 2008); it also has apparent inhibitory effects on a variety of tumors. The Objective of the paper is to study the inhibitory effect of allicin on human gastric cancer cell line SGC-7901.

Materials and Methods

MTT assay and flow cytometry technique were applied to determine the inhibition rate of allicin on human gastric cancer cell line SGC-7901. The results shows that different concentrations of allicin apparently inhibited the gastric cancer SGC7901 cells, cell growth inhibition rates in the experimental groups showed an upward trend with increased allicin concentration, which were concentration-dependent.

Results

Flow cytometry results found that the cell cycle was arrested in the G2/M phase. Allicin has an apparent inhibitory effect on proliferation of gastric cancer cells, and can induce their apoptosis.

Conclusion

Compared with other chemotherapeutic drugs, allicin''s anti-tumor effect is better; and toxic and side effects are relatively small.     

大蒜素降血脂作用及其机理研究

目的：探讨大蒜素的降血脂作用及其机理。方法：将50只昆明种小鼠随机分成5组，对照组、高脂饲料组（模型组）、大蒜素小、中、大剂量＋高脂饲料组。测定大蒜素对血清甘油三酯（TG）、总胆固醇（TC）、高密度脂蛋白胆固醇（HDL-C）以及低密度脂蛋白胆固醇（LDL-C）的影响。测定大蒜素对血清卵磷脂胆固醇脂酰基转移酶（LCAT）、心肌脂蛋白脂酶（LPL）、肝脂酶（HL）活性的影响以及体外对肝脏3-羟基-3-甲基戊二酰CoA（HMG-CoA）还原酶活性的影响。离体胆固醇微胶粒形成实验。结果：大蒜素明显降低喂以高脂饲料小鼠血清TC，TG及LDL-C水平，提高HDL-C含量，且作用与大蒜素剂量呈正相关。大蒜素在不同程度上可升高血清LCAT，心LPL和HL的活性，并在一定程度上降低肝脏HMG-CoA还原酶活性。大蒜素体外实验可抑制胆固醇微胶粒的形成。结论：大蒜素有显著的降血脂效应，其机理一方面可能是促进了脂蛋白之间的代谢与转化，另外可能是因为抑制了肠道胆固醇的吸收、减少了肝脏胆固醇的合成、促进了血清和肝脏甘油三酯的分解。     

大蒜素对大鼠缺血再灌注肝脏损伤的保护作用

目的观察大蒜素对大鼠缺血再灌注肝脏损伤的保护作用。方法雄性SD大鼠,随机分为假手术组、缺血再灌注组(I/R组)和I/R加大蒜素处理组。肝脏缺血再灌注后,分别观察血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)及乳酸脱氢酶(LDH)含量的变化,同时分析肝组织中丙二醛(MDA)含量和超氧化物歧化酶(SOD)的活性。结果肝脏缺血再灌注后,与假手术组比较,血清中ALT、AST、LDH及肝组织中MDA含量均显著增加,而SOD活性显著的降低(P<0.01);经大蒜素处理后,与缺血再灌注组相比较,血清中ALT、AST、LDH及肝组织中MDA含量均降低,而SOD活性增高(P<0.05)。结论大蒜素对大鼠肝脏缺血再灌注损伤有一定的保护作用。     

大蒜素对小鼠S180的抑制作用及NK细胞活性的影响

以小鼠Ｓ１８０为动物模型，观察大蒜素对其抑制作用。大蒜素腹腔注射，连续５天，当大蒜素分别给予２５ｍｇ，ｋｇ＾－１，ｄ和５０ｍｇ，ｋｇ＾－１，ｄ时，则抑瘤率分别为３２．１８％（Ｐ〈０．０５）和５８．５２％，（Ｐ〈０．０１），进一步测定小鼠ＮＫ细胞活性，大蒜素组为５１．３２％，对照组为４４．２２％，两组比较差别不显著（Ｐ〉０．０５）。本文提示：大蒜素能有效的抑制小鼠Ｓ１８０的生长，但对小鼠ＮＫ细胞活性     

大蒜素、氟康唑对医院感染酵母菌的体外抗菌活性研究

目的研究大蒜素、氟康唑对临床分离酵母菌的体外抗菌活性,比较中西药对酵母菌的耐药现状.方法286株酵母菌由住院患者各类感染标本中分离,菌种采用全自动微生物鉴定仪VITEK YBC卡鉴定,用琼脂稀释法测定大蒜素和氟康唑对酵母菌的最低抑菌浓度(MIC),比较大蒜素和氟康唑对酵母菌的MIC50、MIC90.结果经鉴定临床分离的酵母菌中,白色假丝酵母菌最常见,占67.6%,其次为热带假丝酵母菌17.5%、光滑假丝酵母菌8.4%、近平滑假丝酵母菌3.5%等;大蒜素对各类酵母菌均有抑菌作用;氟康唑对白色假丝酵母菌、热带假丝酵母菌及近平滑假丝酵母菌的敏感率较高.结论医院深部酵母真菌感染及耐药性呈上升趋势,提示临床在不明确何种酵母菌感染的情况下,中西药联合使用,可能得到好的疗效.