Erzsébet Háznagy-Radnai

Black Currant Anthocyanins Abrogate Oxidative Stress through Nrf2- Mediated Antioxidant Mechanisms in a Rat Model of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), considered to be one of the most lethal cancers with almost > 1 million deaths reported annually worldwide, remains a devastating disease with no known effective cure. Hence, chemopreventive strategies come into play, offering an effective and safe mode of treatment, ideal to ward off potential cancer risks and mortality. A major predisposing condition, pertinent to the development and progression of HCC is oxidative stress. We previously reported a striking chemopreventive effect of anthocyanin-rich black currant skin extract (BCSE) against diethylnitrosamine (DENA)-initiated hepatocarcinogenesis in rats. The current study aims to elucidate the underlying antioxidant mechanisms of black currant anthocyanins implicated in the previously observed chemopreventive effects against experimental hepatocarcinogenesis. Dietary BCSE (100 and 500 mg/kg) administered four weeks before and 18 weeks after DENA challenge decreased abnormal lipid peroxidation, protein oxidation, and expression of inducible nitric oxide synthase (iNOS) and 3-nitrotyrosine (3-NT) in a dose-responsive fashion. Mechanistic studies revealed that BCSE upregulated the gene expression of a number of hepatic antioxidant and carcinogen detoxifying enzymes, such as NAD(P)H:quinone oxidoreductase, glutathione S-transferase, and uridine diphosphate-glucuronosyltransferase isoenzymes, in DENA-initiated animals. Protein and mRNA expressions of nuclear factor E2-related factor 2 (Nrf2) were substantially elevated with BCSE treatment, providing a direct evidence of a coordinated activation of the Nrf2-regulated antioxidant pathway, which led to the upregulation of a variety of housekeeping genes. The results of our study provide substantial evidence that black currant bioactive anthocyanins exert chemopreventive actions against DENA-inflicted hepatocarcinogenesis by attenuating oxidative stress through activation of Nrf2 signaling pathway.

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. Copyright

Black currant phytoconstituents exert chemoprevention of diethylnitrosamine-initiated hepatocarcinogenesis by suppression of the inflammatory response

Black currant fruits containing high amounts of anthocyanins are known to possess potent antioxidant and anti‐inflammatory properties. We have previously reported that anthocyanin‐rich black currant skin extract (BCSE) inhibits diethylnitrosamine (DENA)‐initiated hepatocarcinogenesis in rats although the underlying mechanisms are not fully understood. Our present study investigates the anti‐inflammatory mechanisms of BCSE during DENA rat liver carcinogenesis. Dietary BCSE (100 or 500 mg/kg) treatment for 22 wk afforded a striking inhibition of DENA‐induced hepatic gamma‐glutamyl transpeptidase‐positive preneoplastic foci in a dose‐responsive fashion. There was a significant increase in hepatic expression of heat shock proteins (HSP70 and HSP90), cyclooxygenase‐2, and nuclear factor‐κB (NF‐κB) in DENA‐exposed rat livers. Dietary BCSE dose‐dependently abrogated all these elevated inflammatory markers. The possible cardiotoxicity of BCSE was assessed by monitoring cardiac functions using transthoracic echocardiography. BCSE‐mediated anti‐inflammatory effects during rat liver carcinogenesis have been achieved without any cardiotoxicity. Our results provide convincing evidence, for the very first time, that suppression of the inflammatory cascade through modulation of the NF‐κB signaling pathway could be implicated, at least in part, in the chemopreventive effects of black currant bioactive phytoconstituents against experimental hepatocarcinogenesis. These results coupled with an excellent safety profile of BCSE support the development of black currant phytochemicals for the chemoprevention of inflammation‐driven hepatocellular cancer.

Iridoids of Stachys species growing in Hungary

Stachys species contain iridoids, for example harpagide, acetylharpagide, aucubin, harpagoside, and ajugoside. The iridoid composition and content of leaves, stems, and inflorescences of ten Stachys species have been compared by use of a TLC–densitometric method. Harpagoside, harpagide, and acetylharpagide proved to be the main iridoids in Stachys officinalis L., St. sylvatica L., St. grandiflora Host., St. macrantha (C. Koch.) Jalas I., St. alpina L., St. palustris L., St. recta L., St. byzantina Koch., and St. germanica L. No iridoids were detected in St. annua L.

TLC and GC Analysis of the Essential Oils of Stachys Species

Species of the Lamioideae subfamily of the family Lamiaceae, including Stachys species, do not contain much essential oil. The first stage of studying the volatile components of Stachys species was characterization of n-hexane extracts by TLC, with sabinene, limonene, linalool, and β-caryophyllene as test materials. On the basis of these results we then studied the volatile compounds by use of GC-FID and GC-MS. By examination of the TLC plates, use of Kováts retention indices, and MS library search we identified components of essential oil fractions obtained from Stachys officinalis II. (L.) Trev., Stachys alpina L., Stachys macrantha (Koch) Stearn, Stachys palustris L., Stachys recta L. subsp. recta, and Stachys annua L. (from Vácrátót) by vapor distillation in accordance with Hungarian Pharmacopoeia VII.

Determination of Stachys palustris iridoids by a combination of chromatographic methods

Stachys palustris L. (Lamiaceae) contains the iridoids harpagide and acetylharpagide. The presence of other components, for example aucubin, can be revealed by TLC and RP HPLC. A readily applicable simple TLC-densitometric method for analysis of aqueous extracts of the plants has been established for comparative studies of aucubin-like iridoids in Stachys palustris.

TLC-densitometry of rosmarinic and caffeic acids in the evaluation of lamiaceae species growing in central europe

A thin-layer chromatographic (TLC)-densitometric method was used for the parallel quantification of rosmarinic acid (RA) and caffeic acid (CA) in crude extracts of Salvia species (Family Lamiaceae), obtained by ultrasonic extraction with 60% methanol. The densitometric measurement was performed in fluorescent mode as it has been published earlier. The applicability of the method has been investigated mainly from the viewpoint of the starting material. Questions are discussed like, what kind of factors should be taken into account, if the drugs are to be characterized, and how the RA and CA contents of samples vary in the plants are discussed. The drugs (plant material) show great differences due to the time of harvest, to the organ composition of drugs, and to the extraction and storage conditions of the stock-solutions prepared from them. The importance of these parameters is illustrated on Salvia species native to Hungary.

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.

Chromatographic determination of iridoids in Stachys recta , and investigation of inorganic elements by X-ray fluorescence spectroscopy

We have isolated five iridoids (harpagide, acetylharpagide, harpagoside, ajugoside, and aucubin) from St. recta L. by a combination of chromatographic methods–NP-TLC, RP-HPLC, and TLC–densitometry. The isolated iridoids were identified on the basis of their physical and spectroscopic properties. Basic information about their structures was obtained from their NMR spectra. X-ray fluorescence spectroscopy can be used for direct determination of inorganic elements in the leaves, stems, and inflorescences of Stachys recta L. We identified K, Ca, Mo, Fe, Co, Ir, Ga, Tl, and S.

Identification of the components of Philadelphus coronarius L. Essential oil

Abstract The volatile constituents of both dried and fresh leaves, twigs and flowers of Philadelphus coronarius L. (Hydrangeaceae) were isolated by hydrodistillation and analyzed by GC/FID and GC/MS. There were major differences between the various oils. For example, epi-13-manool (47.6 %) was the major component of the fresh flower oil, but was not detected in the dried fower oil, whereas isolongifolol (15.5%), 2-nonanol (11.1%) and 7-hydroxycoumarin (9.7%) were the principal components of the dried flower oil. In the oils of both the fresh and dried leaves the major constituent was (E,E)-farnesol, although the proportion of this compound in the fresh leaf oil was considerably higher (37.3%) than that of the dried leaf oil (3.2%). (E,E)-farnesol was also the major component of the fresh twig oil (16.6%), but was absent from the dried twig oil, the major constituent of which was (E,E)-2,4-decadienal (2.4%); however, this was not detected in the fresh twig oil.