Wyniki wyszukiwania - Biblioteka Nauki

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Beneficial effect of alpha-lipoic acid on lipopolysaccharide-induced oxidative stress in bronchoalveolar lavage fluid

100%

Goraca A. , Skibska B.

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tom 59

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nr 2

EN

Lipopolysaccharide (LPS) from gram-negative bacteria is a major factor that contributes to multiple organ failure including lung injury. Among LPS-induced metabolites, reactive oxygen species are considered to play a crucial pathogenic role in the lung damage. In this study, the effect of early administration of an antioxidant, a-lipoic acid (LA), on bronchoalveoar lavage fluid (BALF) lipid peroxidation, hydrogen peroxide (H2O2), sulphydryl group (-SH) concentration and total protein concentration was evaluated in rats with endotoxic shock induced by administration of LPS (Escherichia coli 026:B6, 30 mg/kg, i.v.). The animals were treated intravenously with normal saline or LA (60 mg/kg or 100 mg/kg i.v.) 30 min after LPS injection. Five hours after LPS or saline administration, the animals were sacrificed and BALF was obtained for measurements. The results showed that the levels of oxidative markers, thiobarbituric acid reactive substances (TBARS) and H2O2 were increased significantly in BALF, whereas they were decreased significantly on treatment with LA. The concentrations of -SH groups were significantly increased and total protein concentration was insignificantly decreased in the LPS/LA group. There was no difference in oxidative stress reduction between 60 mg/kg and 100 mg/kg doses. These results indicate that early administration of lipoic acid provides protective effects against endotoxin-induced oxidative stress in the lung and supports the idea that alpha-lipoic acid is a free radical scavenger and a potent antioxidant.

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Wpływ pola magnetycznego niskiej częstotliwości na stres oksydacyjny w tkance mięśniowej szczura

80%

Ciejka E. , Skibska B. , Gorąca A.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2010

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tom Vol. 16, nr 3

224-226

PL

Wolne rodniki (WR) to atomy lub cząsteczki, posiadające wolne niesparowane elektrony. Ich nadmiar prowadzi do rozwoju stresu oksydacyjnego - przyczyny wielu chorób nowotworowych, neurodegeneracyjnych, zapalnych oraz starzenia się organizmu. Głównymi egzogennymi źródłami wolnych rodników są m.in.: zanieczyszczenia przemysłowe, dym tytoniowy, promieniowanie jonizujące oraz pola magnetyczne. Cel. Celem pracy jest ocena działania pola magnetycznego niskiej częstotliwości na proces peroksydacji lipidów w tkance mięśniowej zwierząt doświadczalnych. Materiał i metody. Materiał badawczy stanowiły dorosłe szczury, samce rasy Sprague-Dawley w wieku 3-4 miesięcy. Zwierzęta podzielono na 3 grupy badawcze: I - grupa kontrolna; II grupa poddana działaniu pola magnetycznego o następujących parametrach: 7 mT, 40 Hz, 30 min/dzień, 2 tyg.; III grupa - poddana działaniu pola magnetycznego o parametrach: 7 mT, 40 Hz, 60 min/dzień, 2 tyg. U badanych zwierząt wykonano pomiar stężenia produktów peroksydacji lipidów (TBARS[h1]) w homogenatach tkanki mięśniowej po zakończeniu ekspozycji na działanie pola magnetycznego. Wyniki. Po działaniu zmiennego pola magnetycznego o częstotliwości 40 Hz, indukcji 7 mT, w czasie 30, 60 min/dzień przez 2 tygodnie zaobserwowano wzrost stężenia TBARS w tkance mięśniowej szczura. Wnioski. Pole magnetyczne niskiej częstotliwości (Low Frequency Magnetic Field - LFMF) o parametrach stosowanych w magnetoterapii wywołuje istotne zmiany w procesie generacji reaktywnych form tlenu.

EN

Free radicals (FR) are atoms or molecules with unpaired electrons. They may lead to the development of the oxidative stress, which is a cause of many neoplastic, neurodegenerative, inflammatory diseases and aging of the organism. The main exogenous sources of free radicals are among others: industrial pollution, tobacco smoke, ionizing radiation, and magnetic field. Goal: The aim of this study was to evaluate the influence of the low magnetic field on the parameters of the oxidative stress (TBARS[h2]) in rat's muscles. Materials and methods. Thirty male rats, weight of 280-300 g were randomly divided into three experimental groups: control I and treatment II i III (Low Frequency Magnetic Field LFMF). Animals in the group II were exposed to the LFMF of the following parameters: frequency 40 Hz, induction 7 mT for 0.5 h/day for 14 days (this kind of the ELFMF is mostly used in magnetotherapy), while the group III was subjected to the field: 40 Hz, 7 mT for 1h/day for 14 days. Control rats were kept in the separate room and were not exposed to the to ELFMF. Immediately, after the last exposure, the part of muscles was taken under pentobarbital anaesthesia. The effects of the exposure to the LFMF on the oxidative states were assessed by the measurements of concentration of TBARS in muscles homogenates. Results. Exposure to the LFMF with the following parameters: 40 Hz, 7 mT, 30 and 60min/day for 2 weeks caused significant increase in TBARS concentration in the muscles homogenates. Conclusion. Low magnetic field used in magnetotherapy causes the significant changes of the process of generation of the reactive forms of oxygen in the muscles.

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Actual solubility (S|real.|), level of hydrophilic-lipophilic balance (HLBRequ., HLBD, HLBG) and partition coefficient (log P) of phytochemicals contained in Ext. Camellia sinensis L. aqu. siccum in the light of general Hildebrand- Scatchard-Fedors theory of solubility

71%

Marczynski Z. , Skibska B. , Nowak S. , Jambor J. , Zgoda M. M.

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tom 64

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nr 2

EN

Using the general Hildebrand-Scatchard-Fedors theory of solubility, the mole fraction (x2) of solubility of phytochemicals contained in the dry green tea leaves was calculated which determines the profile of pharmacological activity.The applicative purpose of the study was to estimate the actual solubility of phytochemicals – S|real.| [mol/dm3] in water and in water-ethanol solutions of diversified polarity (εM) for their selective extraction and optimal formulation of oral solid dosage form.The basic physico-chemical and structural quantities of phytochemicals and corresponding mathematical equations of general Hildebrand-Scatchard-Fedors theory of solubility were used to calculate the actual solubility – S|real.| and the level of hydrophilic-lipophilic balance (HLB).The calculated actual solubility values – S|real.| [mol/dm3] collated with correlation equations enabled the assessment of phytochemical capability for the process of mass exchange on phase boundary. Correlation equations for the dependence log P = f (– log S|real.|) point to the structural preferences of phytochemicals in the kinetics of the mass exchange (diffusion) through the natural phase boundary.Calculations and correlations between the values characterizing the actual solubility – S|real.|, media polarity (water, ethanol and their solutions) and the partition coefficient (log P) including the level of hydrophilic-lipophilic balance (HLB) show that basing on thermodynamic components of the general Hildebrand-Scatchard-Fedors theory of solubility, the diffusion profile of phytochemicals contained in the green tea extract (Ext. Camellia sinensis L. aqu. siccum) through the biological phase boundary as well as optimal choice of the extraction medium for selective extraction of the class of phytochemicals can be estimated.

PL

Wykorzystując ogólną teorię rozpuszczalności Hildebranda-Scatcharda-Fedorsa wyliczono ułamek molowy (x2) rozpuszczalności fitozwiązków zawartych w suchym ekstrakcie z liści zielonej herbaty, które decydują o profilu działania farmakologicznego.Aplikacyjnym celem prowadzonych badań było oszacowanie rzeczywistej rozpuszczalności fitozwiązków – S|rz.| (mol/dm3) w wodzie i roztworach wodno-etanolowych o zmiennej polarności (εM) w celu selektywnej ich ekstrakcji i optymalnej formulacji stałej doustnej postaci leku.Do wyliczenia rozpuszczalności rzeczywistej – S|rz.| i poziomu równowagi hydrofilo-lipofilowej (HLB) wykorzystano podstawowe wielkości fizyko-chemiczne i strukturalne fitozwiązków oraz stosowne równania matematyczne z ogólnej teorii rozpuszczalności Hildebranda-Scatcharda-Fedorsa. Wyliczone wielkości rozpuszczalności rzeczywistej – S|rz.| (mol/dm3) zestawione w równaniach korelacyjnych umożliwiły ocenę zdolności fitozwiązków do procesu wymiany masy na granicy faz. Równania korelacyjne dla zależności log P = f (-log S|rz.|) wskazują preferencje strukturalne fitozwiązków w kinetyce procesu wymiany masy (dyfuzji) przez naturalną granicę faz..Z przeprowadzonych obliczeń i korelacji między wielkościami, które charakteryzują rozpuszczalność rzeczywistą – S|rz.|, polarność mediów (woda, etanol i ich roztwory) oraz współczynnik podziału (log P), a w tym również poziom równowagi hydrofilo-lipofilowej (HLB) wynika, że w oparciu o składowe termodynamiczne ogólnej teorii rozpuszczalności Hildebranda-Scatcharda-Fedorsa można oszacować profil dyfuzji fitozwiązków zawartych w ekstrakcie z zielonej herbaty (Ext. Camellia sinensis L. aqu. Siccum) przez biologiczną granicę faz, a także optymalnie dobrać medium ekstrakcyjne w celu selektywnego pozyskiwania klasy fitozwiązków.

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Predicted real solubility (– log x2) and the level of hydrophilic-lipophilic balance (HLBRequ.) of phytochemicals contained in extracts isolated from linden inflorescence (Tiliae flos) with solvents of diversified polarity (εM)

61%

Marczynski Z. , Zgoda M. M. , Stanczak A. , Nowak S. , Jambor J. , Skibska B.

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tom 65

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nr 3

5

Litogenolitic and solubility properties of products obtained from common ivy extract (Hederae helicis e folium) and medium of diversified polarity (ԐM)

61%

Nowak E. , Marczynski Z. , Skibska B. , Nachajski M. J. , Jambor J. , Zgoda M. M.

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tom 65

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nr 1

EN

Introduction: Common ivy (Hedera helix) is a plant used successfully in the treatment of various ailments. This is possible owing to the unique set of substances contained in it such as large amount of saponins, flavonoids, phenolic acids and phytosterols as well as polyacetylenes and coumarins. All these substances have been used in the production of cosmetic and medicinal preparations. Clinical trials on the efficacy and safety of dry ivy leaf extract have shown its high efficacy, comparable to synthetic medications, and better tolerance of herbal drugs. Objective: Investigations were performed on model ivy leaf (Hedera helix) extracts which were created using a medium of diversified polarity (ԐM). Measurements of viscosity and surface activity on phase boundary were performed. During preformulation studies attention was drawn to the possibility of micellar solubilization of cholesterol and selected structures of nonsteroidal anti-inflammatory drugs (NSAIDs) – ketoprofen. Methods: Viscosity measurements of Extractum Hederae helicis e folium aqueous solutions and in 0.1 mol HCl were performed according to the Polish Standard with Ubbelohde dilution viscometer. The surface tension of aqueous solutions – Δγ25 of Hederae helicis e folium extracts was determined according to the Polish Standard with stalagmometric method . Critical micellar concentration (cmc) was calculated. This enabled to evaluate the dependence ΔG0 =2.303 RT× log cmc of the thermodynamic potential of micelle formation (ΔG0 ). Results: It has been confirmed in the conducted comparative studies that aqueous solutions of Extr. Hederae helicis e folium created with maltodextrin as well as with SiO2 – maltodextrin result in micellar solubilization. The increase of granulometric size of cholesterol particle to Ø 1.60 mm decreased the amount of solubilized cholesterol but solubility preferences of the extracts were maintained. Conclusions: Model extracts produced from Hederae helicis e folium with diversified polarity of the extraction medium (water – ethanol) are characterized by appropriate solubility of the components which results not only from the presence of chlorophyll and its derivatives in the extract but also from the technique used for spray drying of the extract.