Effects of peppermint oil and caraway oil on gastroduodenal motility

The effect of enteric-coated (Enteroplant) and non-enteric-coated preparations containing a peppermint-caraway oil combination with 90 mg peppermint oil and 50 mg caraway oil was studied on gastroduodenal motility with stationary manometry in six healthy volunteers. The results showed that: (1) both enteric-coated and non-enteric-coated preparations have effects on the migrating motor complex (MMC); (2) mainly a decrease in the number of contractions and contraction amplitudes is seen during the various phases of the MMC; (3) non-enteric-coated preparations have their effects mainly during the first MMC after administration; (4) enteric-coated preparations have their effects temporally delayed during the second MMC after administration. In conclusion, enteric-coated and non-enteric-coated peppermint-caraway oil combinations are safe preparations, acting locally to cause smooth muscle relaxation.     

Mode of action of peppermint oil and (-)-menthol with respect to 5-HT3 receptor subtypes: binding studies, cation uptake by receptor channels and contraction of isolated rat ileum

Peppermint oil (Mentha × piperita L. (Lamiaceae) has been shown to exert potent antiemetic properties, but its mode of action has not yet been elucidated. Among its active constituents (-)-menthol is the most important. Three different in vitro models were used to investigate the effects on 5-HT(3) receptors (serotonin receptor subtype): [(14)C]guanidinium influx into N1E-115 cells which express 5-HT(3) receptors, isotonic contractions of the isolated rat ileum and equilibrium competition binding studies using a radioactively labelled 5-HT(3) receptor antagonist ([(3)H]GR65630) (3-(5-methyl-1H-imidazol-4-yl)-1-(1-methyl-1H-indol-3-yl)-1-propanone). Both peppermint oil and (-)-menthol inhibited [(14)C]guanidinium influx through 5-HT(3) receptor channels as well as contractions of the ileum induced by serotonin. Neither the peppermint oil nor (-)-menthol, however, was able to displace [(3)H]GR65630 from 5-HT(3) binding sites. It may be concluded that peppermint oil and (-)-menthol exert their antiemetic effect at least partly by acting on the 5-HT(3) receptor ion-channel complex, probably by binding to a modulatory site distinct from the serotonin binding site.     

Spasmolytic activity of Thymus membranaceus essential oil

The spasmolytic activity of Thymus membranaceus essential oil in the duodenum isolated from rat has been investigated. The qualitative and quantitative composition of the essential oil was studied. The essential oil affects the duodenum in two ways, showing a spasmogenic action (due to 1,8-cineole) and, on the other hand, an antagonistic non-competitive effect against the contractions by acetylcholine (due to the phenols and hydrocarbons).     

巴豆油所致的呕吐过程中狗胃肠道电活动的改变

目的　研究巴豆油所致的呕吐过程中狗胃肠道电活动的改变。方法　沿狗胃窦与小肠浆膜面埋植Ag -AgCl双极电极 ;经胃管向胃内注入 10 %巴豆油。结果　首先小肠慢波呈现自下而上的逆行性抑制 ,而后从回肠末端至十二指肠均发生不规律的锋电活动 ,5 8.8%的锋电活动于各段小肠同时发生 ,41.2 %的锋电活动由回肠末端经 1～ 7s逆行传导至十二指肠 ,实验狗伴呕吐前驱症状并随之发生呕吐。分别阻断α和 β受体对巴豆油所引致的胃肠电活动改变及呕吐过程无影响。双侧膈上迷走神经切除后 ,胃肠电活动改变消失 ,但呕吐及其前驱症状仍存 ,呕吐率为迷走神经完整时的 3 1%。结论　巴豆油所致的呕吐过程中狗胃肠道电活动的改变与α和β受体无关 ,迷走神经在其中有重要作用     

A review of the bioactivity and potential health benefits of peppermint tea (Mentha piperita L.)

Peppermint (Mentha piperita L.) is one of the most widely consumed single ingredient herbal teas, or tisanes. Peppermint tea, brewed from the plant leaves, and the essential oil of peppermint are used in traditional medicines. Evidence-based research regarding the bioactivity of this herb is reviewed. The phenolic constituents of the leaves include rosmarinic acid and several flavonoids, primarily eriocitrin, luteolin and hesperidin. The main volatile components of the essential oil are menthol and menthone. In vitro, peppermint has significant antimicrobial and antiviral activities, strong antioxidant and antitumor actions, and some antiallergenic potential. Animal model studies demonstrate a relaxation effect on gastrointestinal (GI) tissue, analgesic and anesthetic effects in the central and peripheral nervous system, immunomodulating actions and chemopreventive potential. Human studies on the GI, respiratory tract and analgesic effects of peppermint oil and its constituents have been reported. Several clinical trials examining the effects of peppermint oil on irritable bowel syndrome (IBS) symptoms have been conducted. However, human studies of peppermint leaf are limited and clinical trials of peppermint tea are absent. Adverse reactions to peppermint tea have not been reported, although caution has been urged for peppermint oil therapy in patients with GI reflux, hiatal hernia or kidney stones.     

Antispasmodic effect of Mentha piperita essential oil on tracheal smooth muscle of rats

Aim of the study

Mentha piperita is a plant popularly known in Brazil as “hortelã-pimenta” whose essential oil is used in folk medicine for its anti-inflammatory, antispasmodic, expectorant actions and anti-congestive. Here, it was investigated the effect of Mentha piperita essential oil (peppermint oil) in rat tracheal rings along with its mechanism of action.

Materials and methods

Tracheal tissue from Male Wistar rats (250–300 g) were used. Peppermint oil was added in cumulative concentrations [1–300 μg/ml] to the tissue basal tonus or pre-contracted by carbachol [10 μM] at 10 min intervals, incubated or not with indomethacin [10 μM], l-N-metyl-nitro-arginine [100 μM], hexamethonium [500 μM], or tetraethylammonium [5mM].

Results

Peppermint oil [100 and 300 μg/ml] inhibited the contractions induced by carbachol, which was reversed by indomethacin, l-N-metyl-nitro-arginine and hexamethonium, but not by tetraethylammonium. These data suggest the participation of prostaglandin E₂, nitric oxide and autonomic ganglions in the peppermint oil relaxant effect and may be correlated with its popular use in respiratory diseases.

Conclusions

Peppermint oil exhibited antispasmodic activity on rat trachea involving prostaglandins and nitric oxide synthase.     

电针对大鼠胃肠动力障碍的调整作用及其神经化学机制

目的:探讨针刺对胃肠运动功能的调整作用及可能的神经化学机制。方法:Wistar大鼠64只,随机分为正常对照组、胃肠动力障碍组、胃肠动力障碍+西药治疗组和胃肠动力障碍+电针治疗组。采用夹尾刺激激怒法制成大鼠胃肠动力障碍模型,用应力传感器记录大鼠胃和十二指肠消化间期移行性复合运动(MMC),采用组织化学技术观测胃、十二指肠肌间神经丛乙酰胆碱酯酶(AChE)、一氧化氮合酶(NOS)阳性神经元的变化。结果:①MMC的改变:与对照组比较,胃肠动力障碍组胃-肠MMC周期、Ⅰ、Ⅱ相延长,Ⅲ相缩短(P<0.01),Ⅲ相频率减慢、幅度下降(P<0.01),胃Ⅲ相发生率降低(P<0.01),胃-肠平均协调收缩率显著下降(P<0.01);西药治疗组、电针治疗组与胃肠动力障碍组比较,胃-肠MMC周期、Ⅰ、Ⅱ相缩短,Ⅲ相延长(P<0.05,0.01),Ⅲ相频率加快、幅度上升(P<0.01),胃Ⅲ相发生率升高(P<0.01),胃-肠平均协调收缩率显著升高(P<0.01);与西药组比较,电针组各指标的改变较明显(P<0.05,0.01)。②胃窦、十二指肠肌间神经丛AChE阳性神经元表达:与对照组比较,胃肠动力障碍组显著减少(P<0.01);与胃肠动力障碍组比较,西药治疗组、电针治疗组显著增加(P<0.01)。③胃窦、十二指肠肌间神经丛NOS阳性神经元表达:与对照组比较,胃肠动力障碍组显著增加(P<0.01);与胃肠动力障碍组比较,西药治疗组、电针治疗组显著减少(P<0.01)。结论:①胃、十二指肠协调运动障碍可能是胃肠动力障碍大鼠发病机制之一;②胆碱能神经、氮能神经紊乱可能是胃肠动力障碍大鼠胃、十二指肠协调运动障碍的神经化学基础;③针刺能改善胃肠动力障碍大鼠胃、十二指肠运动协调性,效应优于胃肠动力药多潘立酮,其作用机理可能与调节ACh、NO神经递质的释放有关。     

Radiosensitizing effects of neem (Azadirachta indica) oil.

Radiosensitization by neem oil was studied using Balbc/3T3 cells and SCID cells. Neem oil enhanced the radiosensitivity of the cells when applied both during and after x-irradiation under aerobic conditions. Neem oil completely inhibited the repair of sublethal damage and potentially lethal damage repair in Balbc/3T3 cells. The cytofluorimeter data show that neem oil treatment before and after x-irradiation reduced the G(2) + M phase, thus inhibiting the expression of the radiation induced arrest of cells in the G(2) phase of the cell cycle. However, SCIK cells (derived from the SCID mouse), deficient in DSB repair, treated with neem oil did not show any enhancement in the radiosensitivity. There was no effect of neem oil on SLD repair or its inhibition in SCIK cells. These results suggest that neem oil enhanced the radiosensitivity of cells by interacting with residual damage after x-irradiation, thereby converting the sublethal damage or potentially lethal damage into lethal damage, inhibiting the double-strand break repair or reducing the G(2) phase of the cell cycle.     

不同促渗剂对蒿甲醚软膏体外透皮吸收的影响

目的:考察促渗剂氮酮、冰片、薄荷油对蒿甲醚软膏体外透皮吸收的影响。方法:使用智能透皮试验仪,选择小鼠腹皮为渗透屏障,对含3种促渗剂及其复配体系的软膏进行体外经皮扩散实验,HPLC测定蒿甲醚的累积透过量和经皮扩散速率。结果:2%氮酮、2%冰片、2%薄荷油,2%氮酮+2%冰片、2%氮酮+2%薄荷油均可以不同程度地促进蒿甲醚软膏的透皮吸收,其促渗效果顺序为2%氮酮+2%薄荷油2%氮酮+2%冰片2%薄荷油2%冰片2%氮酮。结论:薄荷油单用和复配使用对蒿甲醚的体外透皮吸收均有良好的促进作用,复配使用促透效果更佳。     

薄荷油致小鼠肝毒性时-量关系及其机理研究

目的研究薄荷油致小鼠肝毒性的量效、时效关系及自由基损伤机制。方法小鼠口服不同剂量薄荷油,测定其LD50。另取小鼠按不同剂量或不同时间点分组,检查血清ALT等肝功能指标和肝组织形态变化,测定肝组织SOD,MDA。结果小鼠口服薄荷油的LD50为3.0 ml/kg。ALT等肝功能指标在给药后24~48 h达到高峰,72 h可恢复近正常值。与正常组相比,薄荷油中、高剂量组对肝组织损伤显著,随着剂量增大,ALT等肝功能指标升高显著(P<0.05或P<0.01)。薄荷油组与正常组比较,小鼠肝组织中SOD降低而MDA升高(P<0.05),与四氯化碳相似。结论小鼠一次性口服大剂量薄荷油可造成急性肝损伤甚至死亡,并显示有毒性时-效、量-效关系;自由基损伤可能是其肝毒性机制之一。     

薄荷油乳剂经皮给药对小鼠耳肿胀的保护作用

目的:研究薄荷油乳剂经皮给药对小鼠耳肿胀的保护作用。方法:40只雄性小白鼠随机分为正常对照组、阳性对照组、薄荷油乳剂高剂量组、薄荷油乳剂中剂量组、薄荷油乳剂低剂量组。正常对照组耳部涂抹生理盐水,阳性对照组耳部涂抹石灰搽剂,其余均涂抹薄荷油乳剂。以肿胀度和肿胀率为指标区分消炎效果。结果:阳性对照组、薄荷油乳剂高剂量组、薄荷油乳剂中剂量组、薄荷油乳剂低剂量组较正常对照组肿胀度和肿胀率均有降低。结论:石灰搽剂、薄荷油乳剂均具有一定的消炎效果。薄荷油乳剂高剂量组较石灰搽剂组消炎效果明显。     

Relaxant effect of the volatile oil of Rosmarinus officinalis on tracheal smooth muscle

The effects of the volatile oil of Rosmarinus officinalis leaves on the tracheal smooth muscle of rabbit and guinea pig were tested in vitro using isolated tracheal strips. The volatile oil of R. officinalis leaves inhibited the contractions of rabbit tracheal smooth muscle induced by acetylcholine stimulation and the contractions of guinea pig tracheal smooth muscle induced by histamine stimulation. Also, the volatile oil inhibited the contractions of rabbit and guinea pig tracheal smooth muscle induced by high potassium (K+) solution. This inhibition was dose-dependent and reversible. Furthermore, the volatile oil inhibited the contractions of rabbit and guinea pig tracheal smooth muscle induced by acetylcholine and histamine stimulation, respectively, in Ca(2+)-free solution. These data suggest that the volatile oil of R. officinalis leaves has a calcium antagonistic property.     

薄荷油乳剂治疗蠕形螨

为观察薄荷油乳剂对蠕形螨(酒渣鼻)的治疗效果，将活的蠕形螨在显微镜下进行薄荷油乳剂滴药实验．证实药物作用时间3h，则全部杀灭蠕形螨；还对乳剂进行稳定性实验发现有分层和酸败现象。对50例患者进行用药治疗1个月，结果：病情轻者30例有效，在薄荷油乳剂中加入甲硝唑，并口服甲硝唑治疗则效果更好。提示薄荷油乳剂治疗酒渣鼻有一定的疗效。     

Evaluation of mutagenic and antimutagenic activities of neem (Azadirachta indica) seed oil in the in vitro Ames Salmonella/microsome assay and in vivo mouse bone marrow micronucleus test

Aim of the study

The possible mutagenic and antimutagenic activity of neem oil (NO) and its DMSO extract (NDE) were, examined in the Ames Salmonella/microsome mutagenicity test and the mouse bone marrow micronucleus assay.

Materials and methods

Eight different strains of Salmonella typhimurium were, used to study the genotoxicity of neem oil both in the presence and absence of Aroclor-1254 induced rat liver homogenate (S9). Two-dose treatment protocol was, employed to study the cytogenetic activity in micronucleus assay. Similarly, the antimutagenic activity of neem oil and NDE was studied against mitomycin (MMC) and 7,12-dimethylbenz[a]anthracene (DMBA) in the above two test systems.

Results

Neem oil was non-mutagenic in all the eight tester strains of Salmonella typhimurium both in the presence and absence of S9 mix. In the present study, there was no significant increase in the frequency of micronucleated polychromatic erythrocytes (MNPCEs) in neem oil treated groups over the negative control (DMSO) group of animals, indicating the non-clastogenic activity of neem oil in the micronucleus test. Neem oil showed good antimutagenic activity against DMBA induced mutagenicity compared to its DMSO extract. However, neem oil showed comparatively less antimutagenicity against MMC in the Ames assay. In vivo anticlastogenic assays shows that neem oil exhibited better activity against DMBA induced clastogenicity.

Conclusion

These results indicate non-mutagenic activity of neem oil and significant antimutagenic activity of neem oil suggesting its pharmacological importance for the prevention of cancer.     

沙棘果肉油与籽油抗胃溃疡作用的比较及其机制研究

目的：比较研究沙棘果肉油与籽油抗胃溃疡作用并对其机制进行初步探讨。方法：采用大鼠水浸应激性、利血平型、幽门结扎型及乙酸型胃溃疡模型研究比较沙棘果肉油和籽油抗胃溃疡作用；以幽门结扎收集胃液观察对胃液分泌的影响；以甲基橙比色法观察对胃排空的影响；以热板法和扭体法观察其镇痛作用。结果：沙棘果肉油和籽油对大鼠水浸应激性、利血平型、幽门结扎型胃溃疡均有明显的保护作用；对大鼠乙酸型胃溃疡均有明显的促进愈合作用；能抑制大鼠胃酸及胃蛋白酶的分泌，促进胃粘液的分泌；能抑制正常小鼠胃排空；可减少小鼠的扭体次数。结论：沙棘果肉油和籽油均有抗实验性胃溃疡的作用，两者作用强度相似。该作用可能与其抑制胃液分泌，促进胃粘液分泌，抑制胃平滑肌运动及镇痛作用有关。     

薄荷油药理作用和急性毒性的研究

目的研究薄荷油的药理作用。方法采用大鼠利胆、体外溶石、离体平滑肌、角叉菜胶致炎等方法。结果薄荷油120、60、30mg/kg十二指肠给药,对大鼠有明显的利胆作用,并能轻度增加胆汁中胆汁酸的排出量。5、0.5、0.05mg/L在4～5周内对胆固醇结石、胆色素结石无明显溶解作用。薄荷油对豚鼠离体回肠有一定的抑制作用,并能拮抗组胺和乙酰胆碱引起的回肠痉挛。对角叉菜胶致大鼠足肿胀和醋酸致小鼠扭体反应有一定的抑制作用,但对二甲苯致小鼠耳肿胀、小鼠棉球肉芽肿增生、小鼠温浴致痛反应潜伏期无明显影响。小鼠igMTD>4000mg/kg,ipLD     

Gastroprotective effect of essential oil from Croton cajucara Benth. (Euphorbiaceae)

The gastroprotective activity of the essential oil from the bark of Croton cajucara Benth (Euphorbiaceae) was assessed in three different models of experimentally induced gastric ulcer in mice. At oral dose of 100 mg/kg the essential oil reduced gastric lesions induced by hypothermic restraint stress and HCl/ethanol significantly. In the HCl/ethanol model a dose-dependent gastroprotective effect was found. Moreover, significant changes in gastric parameters such as pH, secretion rate and total gastric acid were found after intraduodenal administration of essential oil under ligated pylorus (Shay) conditions. The acute toxicity of essential oil was assessed in mice. The LD50 values were 9.3 and 680 mg/kg for oral and intraperitoneal administrations, respectively. The cytotoxicity of essential oil was studied also. A dose-dependent cell viability inhibition was found in V79 fibroblast cell cultures with an IC50 of 22.9 microg/ml. Our results support the pharmacological study of this essential oil.     

Effect of garlic oil on ethanol induced gastric ulcers in rats

Garlic oil was evaluated for gastroprotective activity against ethanol induced ulcers. Reactive oxygen species are involved in the pathogenesis of these ulcers. The possible involvement of garlic oil in restraining the oxidation process produced in gastric tissue was also investigated. The ulcer index, lipid peroxidation and antioxidant enzyme activity (GPx, catalase, SOD) were determined. Pretreatment with garlic oil in doses of 0.25 and 0.5 mg/kg, 30 min before administration of ethanol (1 mL of 100%) caused a decrease in ulcer index and lipid peroxidation and ameliorated the decrease in antioxidant enzyme levels caused by ethanol. The result suggests that garlic oil possesses antioxidant properties and provides protection against ethanol induced gastric injury.     

Spasmolytic action of the essential oil of Achillea ageratum L. in rats

The spasmolytic activity of Achillea ageratum L. essential oil in isolated rat duodenum has been in estigated. The essential oil was found to present a marked spasmolytic activity against acetylcholine and BaCl₂ via a non-competitive type of antagonism.