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1.
Plants have always been an exemplary source of drugs and many of the currently available medicines have been directly or indirectly derived from them. For this reason, the research, development and use of natural products as therapeutic agents, especially those derived from plants, have been increasing in recent years. A great deal of attention has focused on the naturally occurring antispasmodic phytochemicals as potential drugs for the treatment of cardiovascular diseases. Arterial hypertension is a common and progressive disorder that poses a major risk for cardiovascular and renal diseases. Recent data have revealed that the global burden of hypertension is an important and increasing public health problem worldwide and that the level of awareness, treatment and control of hypertension varies considerably among countries. The research on naturally occurring blood pressure-lowering agents is rapidly expanding due to the high potential of such molecules as new antihypertensive drugs. Recently, a great number of plant-derived substances, such as diterpenoids, have been evaluated as possible antihypertensive agents. Naturally occurring diterpenes such as forskolin and stevioside, exhibit vasorelaxant action and inhibit vascular contractility by different mechanisms of action. In this review we will discuss the mechanisms underlying the hypotensive action displayed by diterpenes and their potential use in human hypertension. We will also discuss the use of these compounds in the treatment of glaucoma, which is characterized by increased intraocular pressure (IOP). 相似文献
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The use of phytotherapy to treat human diseases has its roots in pre-historical times. Despite the modern advances achieved in the field of synthetic chemistry, the most efficient drugs available have their genesis directly or indirectly related with the vegetal kingdom. Indigenous communities have long used plant extracts to treat illnesses. Many of these extracts have shown effective action, with new bioactive compounds being extracted and screened every year. These extracts have also proven to be good sources of therapeutic agents to the treatment of Leishmaniasis. This work highlights some of these agents, while trying to emphasize the importance of plants as a source of new and powerful drugs against this widespread disease. 相似文献
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The performance of a clinical trial for pharmaceutical agents is usually undertaken only after there is likely benefit demonstrated from the use of the putative agent. The consideration of botanical products as pharmaceutical agents must similarly go through a rigorous evaluation process. The present work reviews the recently published phase II study evaluating the effectiveness of black cohosh and red clover in a randomized trial with conjugated equine estradiol/medroxyprogesterone acetate and placebo for the treatment of menopausal symptoms. We analyze the possible reasons why this study failed to show benefit for either botanical product in reducing menopause-related vasomotor symptoms. 相似文献
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May Fern TohJoanna E. Burdette 《Fitoterapia》2011,82(1):67-70
The biological mechanism of action for any botanical extract is a necessary part of discovery to determine pharmacological use and safety. Interestingly, many activities that are governed by endogenous compounds are not fully understood making the characterization of mechanisms elusive. For example, phytoestrogens are being consumed for menopausal symptoms while the biological action of estradiol are still being investigated. Therefore, long term efficacy and safety issues are a challenge in the field. As new activities are associated with new biological pathways, an important component of therapeutic discovery will need to be the re-evaluation of negative or less active natural products to determine their relative use as medicines. 相似文献
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Three new phenolic glycosides, curculigosides F–H (1–3), were isolated from rhizomes of Curculigo orchioides Gaertn. Their structures were elucidated based on comprehensive spectroscopic analyses including IR, MS, 1D- and 2D NMR (HSQC, COSY, and HMBC). Curculigosides F–H (1–3) were evaluated for their anti-HBV activity in vitro using the HBV transfected Hep G2.2.15 cell line. Compound 1 exhibited weak activity with an IC50 value of 2.08 mM on hepatitis B virus (HBV) e antigen (HBeAg) secretion of the HepG2.2.15 cell line. 相似文献
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Yuan Cao Nin-Hua Tan Ji-Jun Chen Guang-Zhi Zeng Yun-Bao Ma Yong-Ping Wu He Yan Jie Yang Lai-Feng Lu Qiang Wang 《Fitoterapia》2010
Three new flavones named 5-carboxymethyl-4′,7-dihydroxyflavone (1), its ethyl ester (2) and butyl ester (3) were isolated from the herb Selaginella moellendorffii Hieron., together with ten known compounds. Their structures were elucidated on the basis of spectroscopic and chemical analysis. Selected compounds were evaluated for their anti-HBV and cytotoxic activity. Among them, compounds 2 and 3 displayed inhibitory activity in vitro on hepatitis B virus (HBV) surface antigen (HBsAg) secretion of the Hep G2.2.15 cell line with IC50 values of 0.17 mg/ml and 0.46 mg/ml, and on HBV e antigen (HBeAg) secretion with IC50 values of 0.42 mg/ml and 0.42 mg/ml, respectively. Compounds 7, 8, 10 and 12 exhibited selective cytotoxicity against the three human cancer cell lines tested. 相似文献
8.
Sautebin L 《Fitoterapia》2000,71(Z1):S48-S57
Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most used drugs worldwide, in spite of their renal and gastric side effects. Medicinal plants may represent a useful source of new effective therapeutic agents, particularly considering the new findings concerning the mediators of inflammation, such as prostaglandins and nitric oxide. In fact, the discovery of two isoforms of the enzyme cyclooxygenase, which catalyzes the conversion of arachidonic acid to prostaglandins, has opened new interesting perspectives in the treatment of inflammatory diseases. As cyclooxygenase, also nitric oxide synthase, the enzyme which converts L-arginine to nitric oxide, exists in two isoforms. It appears that the constitutive isoforms of both enzymes (cyclooxygenase-1 and constitutive nitric oxide synthase) have a regulatory-physiological role, whereas the inducible isoforms (cyclooxygenase-2 and inducible nitric oxide synthase) are involved in inflammation. A number of medicinal plants have been screened for their ability to inhibit cyclooxygenase-2 and/or inducible nitric oxide synthase activity and/or expression. 相似文献
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Wagner H 《Fitoterapia》2011,82(1):34-37
The longstanding, successful use of herbal drug combinations in traditional medicine demands that we find a rationale for their comparative pharmacological and therapeutic superiority to isolated single constituents. The synergistic efficacy of these combinations can be evaluated and verified by Berenbaum's isobole method, followed by clinical studies performed in comparison with synthetic standard drugs. There are many examples of mono- and multi-extract combinations used presently, which exhibit synergistic efficiency based on multi-target mechanisms of action. Among the natural products, gallocatechins of green tea and curcuminoids of ginger are the presently favoured polyphenols for a possible future use in co-medication with antibiotics and standard anticancer drugs. The main targets were found to be COX 1 + 2, NF-κB, and membrane glycoproteins that belong to the ATP-binding cassette (ABC) transporter family. 相似文献
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The extracts from leaves, heartwood, barks and roots of the Streblus asper were investigated for anti-HBV activities, separately. The results suggested that the MeOH extracts of the heartwood, barks, and roots exhibited good anti-HBV activities. Further investigations displayed that ethyl acetate and n-butanol soluble parts of their MeOH extracts showed more significant anti-HBV activities. Moreover, a new lignan, together with 11 known compounds, was isolated from n-butanol-soluble part of MeOH extract of the roots of S. asper. The structures were elucidated by spectroscopic methods, including 1D NMR ((1)H NMR, (13)C NMR), 2D NMR (HMQC, HMBC) and HR-EI-MS experiments. Compounds 1-3 were evaluated for their anti-HBV activities. Honokiol showed significant anti-HBV activity with IC(50) values of 3.14μM and 4.74μM for HBsAg and HBeAg with no cytotoxicity respectively, while lamivudine (3TC, positive control) exhibited weak anti-HBV activity with IC(50) values of 11.81μM and 25.80μM for HBsAg and HBeAg respectively. 相似文献
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广东省湿地公园建设现状与发展策略 总被引：1，自引：0，他引：1
广东省湿地类型多样,湿地资源丰富,具有发展湿地公园的良好条件,随着新一轮绿化广东大行动的开展,湿地公园建设成为生态建设的一个主要切入点,面临着良好的发展机遇。在对广东省湿地公园建设现状、发展条件及存在的问题进行初步研究的基础上,提出广东省湿地公园的发展策略。 相似文献
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综述了植物源农药(包括植物源杀虫剂、植物源杀菌剂、植物源除草剂)的研究和开发应用现状。较详细地介绍了几种典型杀虫植物注要包括楝科植物、豆科鱼藤属植物、卫矛科植物)的杀虫机理和开发应用情况,并讨论了植物源杀虫剂今后研究的几个热点:生物技术在植物源杀虫剂研究中的应用;植物源光活化毒素的研究;杀虫植物资源的进一步调查研究。与植物源杀虫剂相比,植物源杀菌剂和除草剂的研究和应用要少得多。然而目前人们已经在植物体内发现许多具有杀菌、除草活性的物质,因此开发植物资源合成杀菌剂和除草剂具有巨大的潜力。 相似文献
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Pathipati Usha Rani Joish Madhusudhanamurthy Bojja Sreedhar 《Journal of pest science》2014,87(1):191-200
The terpene compounds, α-pinene and linalool were formulated with silica nanoparticles (SNPs) by a simple immersion method and the antifeedant activity of these formulations was evaluated against two major agricultural pests, the tobacco cutworm (Spodoptera litura F.) and the castor semilooper (Achaea janata L.) in laboratory bioassays. The interaction between terpenes and SNPs, shelf-life, suspension stability as well as the bioactivity of the nanoformulations were also studied. Both these terpenes in their pure form are known to deter feeding in several lepidopterous insects. However, formulating these pure terpene compounds with nano silica enhanced their biological activity up to 25 times to S. litura. Fourier transform infrared spectroscopy analysis of these nano botanical formulations indicated the presence of hydrogen bonding between terpenes and the surface of SNPs. Transmission electron microscopy images confirmed the higher aggregation property of the SNPs. Suspension studies validated the improved shelf-life of the nano-biocomposites, while X-ray diffraction (XRD) revealed the amorphous nature of formulations and no crystalline impurities. Adsorption of α-pinene and linalool onto SNPs resulted in an effective formulation that enhanced the antifeedant potential of the individual terpenes against insects while producing longer shelf-life for the terpenes. 相似文献
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“铨水大黄”为甘肃名优药材，在阐明了其主要种类植物学特点和生长地环境条件的基础上，进一步分析了药用部分的微量元素含量和药材特征，并提出了深层开发的建议。 相似文献
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本文在介绍白三叶草植物学特征生物学特性生长发育特点和栽培利用技术要点的基础上,着重介绍了果草问作中白三叶的精作覆膜条播栽培技术的尝试经验. 相似文献
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创建"绿色家园"事关新农村建设大局,显示出林业发展的新机遇,同时在此项活动中也存在一些难点问题发人深省。当前林业部门面临许多新问题需要认真探讨和研究,特别是林改后森林资源培育、加快林地流转、走出城市化绿化误区及国营林场与乡村同步和谐发展等方面的要点问题需要尽快制定新举措,以利发挥林业在新农村建设中的推进作用。 相似文献
17.
Renoz François Demeter Sébastien Degand Hervé Nicolis Stamatios C. Lebbe Olivier Martin Henri Deneubourg Jean‐Louis Fauconnier Marie-Laure Morsomme Pierre Hance Thierry 《Journal of pest science》2022,95(1):381-395
Although synthetic pesticides are still used to control insect pests, greater efforts have been made to develop healthier and more environmentally friendly pesticides. Because of their insecticidal properties, botanical essential oils (EOs) are considered as promising alternatives to the use of synthetic insecticides. However, little is known about mechanisms underlying the insecticidal activity of most these natural compounds. In the present study, we evaluated the contact toxicity and the modes of action of the EO from Mentha arvensis against the granary weevil, Sitophilus granarius L. (Coleoptera: Curculionidae), a cosmopolitan insect pest that causes extensive damage to stored cereals. M. arvensis EO caused high contact toxicity in S. granarius adults, resulting in a rapid paralysis and rapid alteration of walking behavior. Our label-free quantitative proteomics approach revealed that M. arvensis EO induced dramatic physiological changes in exposed insects. The majority of the differentially expressed proteins (DEPs) were upregulated and are related to the development and functioning of the muscular and nervous systems, cellular respiration, protein synthesis, and detoxification. These results suggest that M. arvensis essential oil is capable of affecting a variety of biological processes, and shed light on the repair mechanisms put in place in surviving insects to counter the damage inflicted. This work opens new perspectives on the proposed mechanisms of insecticidal activity of a promising EO for controlling pests of stored cereals and may represent a first step in the development of novel bio-rational insecticides.
相似文献18.
Activity-guided fractionation of Euphorbia humifusa for anti-HBV activity led to the isolation of two novel sesquiterpenoids, named humifusane A (1) and humifusane B (2). Their structures were elucidated by spectral data to show that they have a caryophyllane-type precursor structure. The two new sesquiterpenoids showed anti-HBV activities through specifically inhibiting the secretion of HBsAg in HepG2.2.15. 相似文献
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《Fitoterapia》2013
Presently herbal medicines are being used by about 80% of the world population for primary health care as they stood the test of time for their safety, efficacy, cultural acceptability and lesser side effects. The discovery of platelet activating factor antagonists (PAF antagonists) during these decades are going on with different framework, but the researchers led their efficiency in studying in vitro test models. Since it is assumed that PAF play a central role in etiology of many diseases in humans such as asthma, neuronal damage, migraine, cardiac diseases, inflammatory, headache etc. Present days instinctively occurring PAF antagonist exists as a specific grade of therapeutic agents for the humans against these and different diseases either laid hold of immunological or non-immunological types. Ginkgolide, cedrol and many other natural PAF antagonists such as andrographolide, α-bulnesene, cinchonine, piperine, kadsurenone, different Piper species' natural products and marine origin plants extracts or even crude drugs having PAF antagonist properties are being used currently against different inflammatory pathologies. This review is an attempt to summarize the data on PAF and action of natural PAF antagonists on it, which were evaluated by in vivo and in vitro assays. 相似文献