In vitro activity of uva-ursi against cytochrome P450 isoenzymes and P-glycoprotein

Plant-Derived Products as Antibacterial and Antifungal Agents in Human Health Care

A number of papers reporting antimicrobial properties of extracts, essential oils, resins and various classes of compounds isolated from higher plants have been published in recent years; however, a comprehensive analysis of plant-derived antimicrobial agents currently applied in practice for the improvement of human health is still lacking. This review summarizes data on clinical efficacy, antimicrobial effects and the chemistry of commercially available antibacterial and antifungal agents of plant origin currently used in the prevention and treatment of gastrointestinal, oral, respiratory, skin, and urinary infections. As a result of an analysis of the literature, more than 40 plant-derived over-the-counter pharmaceuticals, dietary supplements, cosmetics, herbal medicines, and functional foods containing complex mixtures (e.g. Glycyrrhiza glabra extract, Melaleuca alternifolia essential oil, and Pistacia lentiscus resin), pure compounds (e.g. benzoic acid, berberine, eucalyptol, salicylic acid and thymol) as well as their derivatives and complexes (e.g. bismuth subsalicylate and zinc pyrithione) have been identified. The effectiveness of many of these products is illustrated by results of clinical trials and supported by data on there in vitro antimicrobial activity. A broad spectrum of various commercial products currently available on the market and their welldocumented clinical efficacy suggests that plants are prospective sources for the identification of new types of antimicrobial agents in future. Innovative approaches and methodologies for effective proof-of-concept research and the development of new types of plant-derived products effective against recently emerging problems related to human microbial diseases (e.g. antimicrobial resistance) are also proposed in this review.

Human cytochrome P450 enzymes 5-51 as targets of drugs and natural and environmental compounds: mechanisms, induction, and inhibition - toxic effects and benefits

Cytochrome P450 (P450, CYP) enzymes have long been of interest due to their roles in the metabolism of drugs, pesticides, pro-carcinogens, and other xenobiotic chemicals. They have also been of interest due to their very critical roles in the biosynthesis and metabolism of steroids, vitamins, and certain eicosanoids. This review covers the 22 (of the total of 57) human P450s in Families 5-51 and their substrate selectivity. Furthermore, included is information and references regarding inducibility, inhibition, and (in some cases) stimulation by chemicals. We update and discuss important aspects of each of these 22 P450s and questions that remain open.

Internet claims on dietary and herbal supplements in advanced nephropathy: truth or myth

BACKGROUND

The use of complementary/alternative medicine has garnered rising interest in recent years. Natural products including herbs, vitamins, and minerals are the most popularly consumed. The Internet is a ubiquitous source of information/market for these supplements.

AIM

To systematically evaluate the dietary and herbal supplement recommended for patients with CKD and ESRD on the Internet, and try to distinguish between the claim of the manufacturer and proven scientific data.

METHODS

A questionnaire assessing each website was formulated. Each product ingredient was recorded in the questionnaire by two independent reviewers and statistically analyzed.

RESULTS

Of the 184 websites, 28% claimed to decrease CKD progression, 60% did not advise to consult a doctor before taking the supplement, and >90% did not mention any potential drug interaction, disease interaction, or caution in use during pregnancy or in children. The ten common plant ingredients claiming to be beneficial in kidney diseases were uva ursi, dandelion, parsley, corn silk, juniper, celery, buchu, horsetail, marshmallow, and stinging nettle. In contrast to their claims, these substances were not adequately studied in humans. The available animal studies showed detrimental effects and potential drug interactions with commonly used medications in the CKD/ESRD population.

CONCLUSIONS

Nephrologists need to be cognizant of the lack of substantiated proven benefits of these substances and of the potential adverse effects in the animal models that can translate to the patients. Most importantly, the policy needs to change regarding the regulation of these products to prevent patient harm and misinformation.

A RP-HPLC-DAD-APCI/MSD method for the characterisation of medicinal Ericaceae used by the Eeyou Istchee Cree First Nations

INTRODUCTION

Ericaceae medicinal plants are traditionally used by the Eeyou Istchee Cree and other northern peoples of North America to treat type 2 diabetic symptoms. Because of the importance of phenolics as potential cures for degenerative diseases including type 2 diabetes, an analytical method was developed to detect them in the leaf extracts of 14 Ericaceae plants.

OBJECTIVE

To develop an optimised method which is applicable to a relatively large number of Ericaceae plants using their leaf extracts. For this purpose phenolics with a wide range of polarity, including a glucosylated benzoquinone, two phenolic acids, three flavanols, a flavanone, a flavone and five flavonols, were included in this study.

METHODOLOGY

Characterisation of phytochemicals in extracts was undertaken by automated matching to the UV spectra to those of an in house library of plant secondary metabolites and the authentication of their identity was achieved by reversed phase-high-performance chromatography-diode array detection-atmospheric pressure chemical ionisation/mass selective detection.

RESULTS

Twenty-six phenolics were characterised within 26 min of chromatographic separation in 80% ethanol extracts of 14 Ericaceae plants. The calibration curves were linear within 0.5-880 microg/g dry mass of the plant with regression values better than 0.995. The limits of detection ranged from 0.3 for microg/mL for (+)-catechin to 2.6 microg/mL for chlorogenic acid. This is a first study dealing with relatively large number of Ericaceae extracts and is applicable to other plants of same family.