Pharmacokinetic and pharmacodynamic herb-drug interactions-part I. Herbal medicines of the central nervous system.

Unlike conventional drug substances, herbal medicines are composed of a complex of biologically active compounds. Therefore, the potential occurrence of herb-drug interactions is even more probable than for drug-drug interactions. Interactions can occur on both the pharmacokinetic and pharmacodynamic level. Herbal medicines may affect the resulting efficacy of the concomitantly used (synthetic) drugs, mainly on the pharmacokinetic level, by changing their absorption, distribution, metabolism, and excretion. Studies on the pharmacodynamic interactions of herbal medicines and conventional drugs are still very limited. This interaction level is related to the mechanism of action of different plant constituents. Herb-drug interactions can cause changes in drug levels and activities and lead to therapeutic failure and/or side effects (sometimes toxicities, even fatal). This review aims to provide a summary of recent information on the potential drug interactions involving commonly used herbal medicines that affect the central nervous system (Camellia, Valeriana, Ginkgo, Hypericum, Humulus, Cannabis) and conventional drugs. The survey databases were used to identify primary scientific publications, case reports, and secondary databases on interactions were used later on as well. Search keywords were based on plant names (botanical genera), officinal herbal drugs, herbal drug preparations, herbal drug extracts.

Proposed mechanisms of action of herbal drugs and their biologically active constituents in the treatment of coughs: an overview.

Various medicinal plants find their use in cough treatment, based on traditions and long-term experience. Pharmacological principles of their action, however, are much less known. Herbal drugs usually contain a mixture of potentially active compounds, which can manifest diverse effects. Expectorant or antitussive effects, which can be accompanied by others, such as anti-inflammatory or antibacterial, are probably the most important in the treatment of coughs. The aim of this review is to summarize the current state of knowledge of the effects of medicinal plants or their constituents on cough, based on reliable pharmacological studies. First, a comprehensive description of each effect is provided in order to explain the possible mechanism of action in detail. Next, the results related to individual plants and substances are summarized and critically discussed based on pharmacological in vivo and in vitro investigation.

Natural Products for the Prevention and Treatment of Common Cold and Viral Respiratory Infections.

The common cold is generally considered a usually harmless infectious disease of the upper respiratory pathway, with mostly mild symptoms. However, it should not be overlooked, as a severe cold can lead to serious complications, resulting in hospitalization or death in vulnerable patients. The treatment of the common cold remains purely symptomatic. Analgesics as well as oral antihistamines or decongestants may be advised to relieve fever, and local treatments can clear the airways and relieve nasal congestion, rhinorrhea, or sneezing. Certain medicinal plant specialties can be used as therapy or as complementary self-treatment. Recent scientific advances discussed in more detail in this review have demonstrated the plant's efficiency in the treatment of the common cold. This review presents an overview of plants used worldwide in the treatment of cold diseases.

Combination Therapy of Carnosic Acid and Methotrexate Effectively Suppressed the Inflammatory Markers and Oxidative Stress in Experimental Arthritis.

BACKGROUND: Combination therapy with methotrexate (MTX) is the most common therapeutic strategy used for the treatment of patients with rheumatoid arthritis (RA). In this study, we combined the natural compound carnosic acid (CA) with MTX to reduce inflammation and oxidative stress in adjuvant arthritis (AA). METHODS: AA was induced in 6-8 rats per group. MTX was administrated twice a week at a dose of 0.3 mg/kg b.w., while CA was administered daily at a dose of 100 mg/kg both in monotherapy and in combination with MTX. Plasma samples were collected on the 14th, 21st, and 28th day. Body weight and hind paw volume were measured once a week. RESULTS: We found that, mainly, the CA + MTX combination significantly reduced the hind paw swelling, the levels of IL-17A, MMP-9, and MCP-1 in plasma, and GGT activity in joint homogenates. The mRNA expression of HO-1, catalase, and IL-1ß in the liver were significantly improved by CA + MTX only. Our results indicate that adding CA to MTX treatment could be a good therapeutic option for patients suffering from RA. CONCLUSIONS: The addition of CA to methotrexate treatment significantly improved its efficacy in decreasing the development of AA by inhibiting the markers of inflammation and oxidative stress.

The Importance of Pine Species in the Ethnomedicine of Transylvania (Romania).

The geographical and ecological features of Transylvania enable the wide ethnobotanical use of pine species. The aim of this study was to survey the current ethnomedicinal and other traditional use of pine species of Hungarian-speaking ethnic groups in Transylvania and to compare them with earlier reports performed in Transylvania and from other countries related to the Carpathian Basin. Information on pine species was obtained using semi-structured interviews with 515 Transylvanian informants from 18 villages in the period 2007-2019. The young shoots of Abies alba Mill., Picea abies (L.) H. Karst., Pinus nigra J. F. Arnold, and Pinus sylvestris L. were applied to treat respiratory diseases, while the resin was used for dental problems. Syrup and decoction were made from the cones of all species, except Abies alba. Picea abies was the most frequently documented with seven preparations from different parts (even needles), and this species was mentioned in the treatment of 21 diseases. The least recorded was Abies alba, which was applied for coughs and decayed teeth. We recorded the use of the cones and needles of Picea abies for dyspnoea, thyroid glands, and kidney disorders, previously unknown in ethnomedicinal literature. Our data on the pine species confirm their current use and significance in Transylvania.

Treatment of Gastrointestinal Disorders-Plants and Potential Mechanisms of Action of Their Constituents.

The worldwide prevalence of gastrointestinal diseases is about 40%, with standard pharmacotherapy being long-lasting and economically challenging. Of the dozens of diseases listed by the Rome IV Foundation criteria, for five of them (heartburn, dyspepsia, nausea and vomiting disorder, constipation, and diarrhoea), treatment with herbals is an official alternative, legislatively supported by the European Medicines Agency (EMA). However, for most plants, the Directive does not require a description of the mechanisms of action, which should be related to the therapeutic effect of the European plant in question. This review article, therefore, summarizes the basic pharmacological knowledge of synthetic drugs used in selected functional gastrointestinal disorders (FGIDs) and correlates them with the constituents of medicinal plants. Therefore, the information presented here is intended as a starting point to support the claim that both empirical folk medicine and current and decades-old treatments with official herbal remedies have a rational basis in modern pharmacology.

Ginkgo biloba Food Supplements on the European Market - Adulteration Patterns Revealed by Quality Control of Selected Samples.

The aim of this study was to prove whether Ginkgo biloba food supplements on the European market comply with pharmaceutical quality, and whether their composition satisfies the European Pharmacopoeia criteria. Medicinal products containing a standardised Ginkgo leaf extract are used for the improvement of cognitive impairment and quality of life in mild dementia. Further, Ginkgonis folium is used for the treatment of peripheral circulation disorders. Pharmacopoeial Ginkgo dry extract contains 22.0 - 27.0% flavonoids and 5.4 - 6.6% terpene lactones (ginkgolides, bilobalide). In addition to its widespread use as an herbal medicine (herbal medicinal product), the same extract can be an ingredient in food supplements. The content of active secondary metabolites was quantified in a number of European food supplements containing Ginkgo dry extract or Ginkgo leaf. Flavonoids were quantified using a modified pharmacopoeial HPLC-UV method, and terpene lactones (ginkgolides A, B, C, and bilobalide) using LC-MS/MS. Some Ginkgo leaf supplement samples were also analysed by microscopy. The quality of food supplements on the European market is dubious. In this paper, we present selected examples of several methods of adulteration and falsification, including higher/lower doses of Ginkgo dry extract or Ginkgo leaf than declared and the addition of undeclared extraneous materials. These examples reveal several patterns in the manufacturing of adulterated products.

[Phenolic compounds in leaves insertions of Mentha × villosa Huds. cv. Snezná]. / Fenolové látky v listových inzerciách Mentha × villosa Huds. cv. Snezná.

Lamiaceae plants mostly accumulate active ingredients in their leaves. The subfamily Nepetoideae, including the genus Mentha L., is characterized by the presence of essential oil and antioxidant phenolics, chiefly hydroxycinnamic acids with predominance of rosmarinic acid, and flavonoids. Mentha × piperita and M. spicata are the most broadly used mints in both medicine and industry, while M. x villosa is less known in our country. Herbal drugs in the form of leaves are usually analysed unpartitioned, while single leaves insertions have only been studied occasionally. Therefore, the aim of this work was the quantification of the active compounds content in the leaves pairs of Mentha × villosa Huds. cv. Snezná, using pharmacopoeial methods: total hydroxycinnamic derivatives expressed as rosmarinic acid (THD) and luteolin-type flavonoids. THD content ranged from 6.7% to 9.4% in the leaves pairs water extracts, and from 6.6% to 14.0% in methanol extracts. Flavonoids contents, expressed as luteolin-7-O-glucoside, ranged from 4.0% to 8.8% in water extracts, and from 4.0% to 10.5% in methanol extracts. Antioxidant activity (DPPH) expressed as SC50 ranged from 10.2 to 16.9 µg.ml-1 (drug dry weight) in water extracts, and from 10.7 to 21.6 µg.ml-1 in methanol extracts. The highest content of phenolic compounds as well as the highest antioxidant activity were found to be in the top sheet, while the lowest content of phenolic compounds and lowest antioxidant activity were detected in the leaves of the middle stem part.Key words: Mentha × villosa Huds cv. Snezná hydroxycinnamic derivatives rosmarinic acid luteolin-7-O-glucoside DPPH.

Elemental analysis of Ginkgo biloba leaf samples collected during one vegetation period.

The object of our work was the identification and quantification of inorganic elements in Ginkgo biloba L. leaves (Ginkgonis folium, Ginkgoaceae) by X-ray fluorescence analysis. The plant material was obtained from a 50-years-old female tree at the Comenius University Botanical Garden (Bratislava, Slovakia). Leaves were collected from early May to late September, with the last sample consisting of fallen leaves. The elements analyzed were: phosphorus, sulfur, potassium, calcium, scandium, iron, zinc, yttrium, molybdenum, tellurium, samarium, gadolinium, dysprosium, iridium, thallium and lead. The amounts of the monitored heavy metals were below the limits specified in Ph. Eur. 7 and PhS 1.

Identification of triterpenes from milkweed (Asclepias syriaca).

The chloroform extract of Asclepias syriaca stem were investigated. Three triterpenes were isolated by TLC, VLC, and preparative chromatography, and their structures established by one and two-dimensional NMR spectroscopy. Lupenyl acetate has been isolated for the first time from A. syriaca; this is thefirst representative of a triterpene bearing a lupane skeleton in this species. In addition, alpha-amyrin acetate and alpha-amyrin butyrate were isolated.

Antiinflammatory activities of Hungarian Stachys species and their iridoids.

The antiinflammatory activities of aqueous extracts prepared from the aerial parts of ten Hungarian Stachys species were investigated in vivo in the carrageenan-induced paw oedema test after intraperitoneal and oral administration to rats. Some of the extracts were found to display significant antiphlogistic effects when administered intraperitoneally and orally; in particular, the extracts of S. alpina, S. germanica, S. officinalis and S. recta demonstrated high activity following intraperitoneal administration. At the same dose of 5.0 mg/kg, these extracts exhibited similar or greater potency than that of the positive control diclofenac-Na. The main iridoids present in the investigated extracts, ajugoside, aucubin, acetylharpagide, harpagide and harpagoside, were also assayed in the same test, and high dose-dependent antiphlogistic effects were recorded for aucubin and harpagoside. These results led to the conclusion that most probably iridoids are responsible for the antiinflammatory effect of Stachys species, but other active constituents or their synergism must also be implicated in the antiinflammatory effect.

Cytotoxicity of water extracts from leaves and branches of Philadelphus coronarius L.

Philadelphus coronarius L. is big, leggy and deciduous old-fashioned shrub known for its fragrant white flowers in the late spring. Some members of genus Philadelphus L. are known for their antibacterial, antiradical and immunomodulatory effects. Therefore, these herbs represent prospective sources for the isolation of active substances with desired effects. We have investigated the cytotoxicity effects of water extracts from leaves and branches of Philadelphus coronarius L. (Hydrangeaceae). A431 cells (human skin carcinoma cell line) and the human breast adenocarcinoma cell line (MCF-7) were treated with various doses of individual extracts (0,1-100 microg dry matter/ml) for 24 h and 72 h. The highest toxic effects of both plant parts extracts were observed on MCF-7 cells regardless the time of treatment. Cells A431 were less sensitive to toxic effects of leaves and branches extracts but the time dependence was present with the tendency of increased toxicity after chronic treatment. There were no differences in the extent of toxic effects between branches and leaves extracts. The results obtained so far will provide the basis for the future studies with isolated active substances from these extracts.