Arunas Savickas

Uncoupling and antioxidant effects of ursolic acid in isolated rat heart mitochondria.

Ursolic acid (1), a pentacyclic triterpene acid, is one of the major components of certain traditional medicinal plants and possesses a wide range of biological effects, such as anti-inflammatory, antioxidative, and cytotoxic activities. Furthermore, 1, when present at 1.6-5 ng/mL concentrations in commercial herbal preparations used for patients with cardiac disorders, may also exert pro-cardiac activities. There are several indirect suggestions that the cardioprotective mechanism of ursolic acid could involve the mitochondria; however the mechanism of action is still not known. Therefore, the effects of 0.4-200 ng/mL ursolic acid (1) on the functions of isolated rat heart mitochondria oxidizing either pyruvate and malate, succinate, or palmitoyl-l-carnitine plus malate were investigated. It was found that 1 induced a statistically significant uncoupling of oxidative phosphorylation. A statistically significant decrease in H₂O₂ production in the mitochondria was observed after incubation with 5 ng/mL 1. This effect was comparable to the effectiveness of the classical uncoupler carbonyl cyanide 3-chlorophenylhydrazone. Since mild mitochondrial uncoupling has been proposed as one of the mechanisms of cardioprotection, the present results indicate that ursolic acid (1) has potential use as a cardioprotective compound.

Direct Effects of (−)-Epicatechin and Procyanidin B2 on the Respiration of Rat Heart Mitochondria

Flavonol (−)-epicatechin and its derived dimer procyanidin B2, present in high amounts in cocoa products, have been shown to exert beneficial effects on the heart and cardiovascular system; however, their mechanism of action has not been fully elucidated. We studied effects of (−)-epicatechin and procyanidin B2 on the oxidative phosphorylation of isolated rat heart mitochondria. (−)-Epicatechin and procyanidin B2 had stimulating effect (up to 30% compared to control) on substrate-driven (State 2) mitochondrial respiration. Their effect was dependent on the respiratory substrates used. (−)-Epicatechin at higher concentrations (from 0.27 µg/mL) significantly decreased (up to 15%) substrate- and ADP-driven (State 3) mitochondrial respiration in case of pyruvate and malate oxidation only. Procyanidin B2 (0.7–17.9 ng/mL) inhibited State 3 respiration rate up to 19%, the most profound effect being expressed with succinate as the substrate. (−)-Epicatechin at concentrations of 0.23 µg/mL and 0.46 µg/mL prevented loss of the cytochrome c from mitochondria when substrate was succinate, supporting the evidence of membrane stabilizing properties of this flavonol. Thus, both (−)-epicatechin and procyanidin B2 directly influenced mitochondrial functions and the observed effects could help to explain cardiometabolic risk reduction ascribed to the consumption of modest amounts of cocoa products.

Estimation of the combined effect of Eleutherococcus senticosus extract and cadmium on liver cells.

Cadmium (Cd) is an important industrial pollutant, even though its mechanism of toxicity has not been completely clarified. Cd2+ is toxic to a wide range of organs and tissues. Liver and kidneys are the primary target organs of cadmium toxicity. Cd2+ induces apoptosis and causes necrotic cell death in certain pathophysiological situations. Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. has many beneficial features. It supports the organisms stress response, immune system, and endocrine system, including the adrenal glands, spleen, and thymus gland. The aim of our study was to investigate the effects of the Eleutherococcus senticosus (ES) liquid extract on the accumulation of Cd2+ in liver and on the mitotic and apoptotic activity of liver cells after chronic intoxication by Cd2+. Experiments were carried out on white laboratory mice. Laboratory mice were given to drink solutions of different Cd2+ and ES concentrations for 8 weeks. Cd2+ concentration in mouse liver was detected using atomic absorption spectroscopy. Mitotic and apoptotic activity of liver cells was expressed as an estimated number of mitotic and apoptotic cells in randomly selected reference areas in a histological slide. ES combined with CdCl2 leads to a significant decrease of cadmium concentration in the blood and liver of experimental mice. ES decreased the cadmium‐induced mitotic and apoptotic activity of liver cells.

Antifungal and Antibacterial Activity of Propolis

Propolis is a natural substance collected by bees from local flora. Propolis is increasingly used in health-food manufacturing practices since in addition to the antibacterial, antifungal, and antiviral characteristics, it also strengthens the immunity and has a strong antioxidative effect. We investigated the chemical composition and antimicrobial activity of 10 samples of propolis, which were collected in different regions of Lithuania. The highest concentrations of phenolic compounds, the main active substances of propolis, were found in the samples which were collected from the hives located in the proximity of forests of a mixed type. The highest amounts of flavonoids were detected in propolis samples that were obtained from the bee hives located in the meadows All samples of propolis ethanolic extract were active against gram-positive, gram-negative bacteria and fungi. The antimicrobial activity was higher against gram-positive than against gram-negative bacteria. One propolis sample showed relatively strong activity against Candida albicans - minimum inhibitory concentration (MIC) - 0.009 g/100ml of phenolic compounds. The antimicrobial activity of propolis may be due to the synergistic effect of phenolic compounds, terpenoids, aromatic and aliphatic acids.

Influence of propolis water solution on heart mitochondrial function

The effect of propolis water solution (PWS) on the respiration of rat heart mitochondria with NAD‐linked (pyruvate + malate), FAD‐linked (succinate) substrates and fatty acids (palmitoyl‐L‐carnitine) was investigated in this study. PWS at the lowest concentration of 4 μgmL−1 of phenolic compounds (PC) had no effect on mitochondrial respiration with all investigated substrates. PWS at concentrations of 63 and 125 μ gmL−1 of PC caused a significant decrease of basal (24 and 54%) and maximal (58 and 70%) respiration rates with succinate as substrate. At these PWS concentrations the oxidation of pyruvate + malate and palmitoyl‐L‐carnitine was diminished to a lower degree: the basal respiration rate decreased by 13–18% and the maximal respiration rate by 15–28%. Succinate oxidation was affected, probably because of the inhibition of succinate dehydrogenase by the 1,2‐benzenedicarboxylic acid esters found in PWS. The PWS‐caused decrease in the mitochondrial respiration rate with pyruvate + malate and fatty acids could be due to diminished activities of respiratory chain complexes and/or ADP/ATP translocator.

Analysis of Phenolic Acids in Propolis Using the High-Performance Liquid Chromatography Technique

The aim of the research was to analyze the chemical composition of Lithuanian propolis and to compare it with the chemical composition of propolis in neighboring countries (Latvia and Poland) according to the predominant flora in the collecting places and the quality of raw material collecting process. The article describes the qualitative analysis of phenolic acids in propolis using the high-performance liquid chromatography technique. Studies showed that the quantitative and qualitative composition of phenolic acids in propolis depended on what plants the bees in the area collected substances for the raw material of propolis. In addition to that, it was found that the amount of active substances was higher in propolis extracts produced from propolis collected from areas characterized by the predominance of deciduous trees. The predominant phenolic acids were determined to be ferulic and coumaric acids that may be among the main indicators of quality in the standardization of the raw material and preparations of propolis. Experimental studies showed that the process of the collection of propolis influence its chemical composition too. The production of pharmaceutical preparations requires the regulation of the technique and the conditions of the collection of propolis, ensuring high quality of the collection of the raw material.

Influence of Echinacea purpurea (L.) Moench extract on the toxicity of cadmium.

Abstract:  Echinacea purpurea (L.) Moench (EP) has many beneficial features, especially strengthening the immune system. Cadmium (Cd) is a ubiquitous metal and cumulative poison that may cause liver and kidney damage and the formation of neoplasia. In this article, the changes in organs and metabolism, the accumulation of various levels of Cd in tissues, and the effects of EP liquid extract on Cd‐induced changes in mice were investigated. Experiments were carried out on the white laboratory mice. Solution of different Cd and EP concentrations were given to drink and experiments were performed. The concentration of Cd in mice blood, liver, kidneys, heart, spleen, skeletal muscle was determined using an electrothermal graphite furnace atomic absorption spectrophotometer Perkin–Elmer/Zeeman 3030. Long time per os of extract of EP combined with Cd leads to a significant increase of Cd concentration in blood and investigated organs of experiment mice.

Assessment of the Effect of Echinacea purpurea (L.) Moench on Apoptotic and Mitotic Activity of Liver Cells during Intoxication by Cadmium

Abstract:  Cadmium (Cd2+) is an important industrial pollutant, although its mechanism of toxicity has not been completely clarified. Cd2+ is toxic to a wide range of organs and tissues, however, the primary target organs of Cd2+ toxicity are the liver and kidney. Echinacea purpurea stimulating one or another tread of the immune system stimulates the expression of immunoglobulins and interferons. The experiments were performed on white laboratory mice using intraperitoneal (i.p.) injections 0.05 LD50 amount of CdCl2 solution. Two groups of mice were injected by Echinacea purpurea liquid extract: one 0.05 LD50 and the other 0.1 LD50. In this article, the Cd2+ distribution in internal organs, its effect on the mitotic and apoptotic activity of liver cells, as well as effects of Echinacea purpurea liquid extract on Cd2+‐induced changes in mice were investigated. Cd2+ concentration in mice blood, liver, and kidney was detected by atomic absorption spectroscopy. Long‐term injections of extract of Echinacea purpurea combined with Cd2+Cl2 leads to the significant increase of Cd2+ concentration in blood and investigated organs of experimental mice. Mitotic and apoptotic activity of liver cells was expressed as the estimated number of mitotic and apoptotic liver cells in randomly selected reference areas in histological slide. Echinacea purpurea decreases the mitotic activity of liver cells induced by Cd2+ and increases apoptotic activity of the liver cells.

Evaluation of Beeswax Influence on Physical Properties of Lipstick Using Instrumental and Sensory Methods

The aim of this study was to optimize the lipsticks formulation according to the physical properties and sensory attributes and investigate the relationship between instrumental and sensory analyses and evaluate the influence of the main ingredients, beeswax and oil, with analysis of lipsticks properties. Central composite design was used to optimize the mixture of oils and beeswax and cocoa butter for formulation of lipsticks. Antioxidant activity was evaluated by DPPH free radical scavenging method spectrophotometrically. Physical properties of lipsticks melting point were determined in a glass tube; the hardness was investigated with texture analyzer. Sensory analysis was performed with untrained volunteers. The optimized mixture of sea buckthorn oil and grapeseed oil mixture ratio 13.96 : 6.18 showed the highest antioxidative activity (70 ± 0.84%) and was chosen for lipstick formulation. According to the sensory and instrumental analysis results, optimal ingredients amounts for the lipstick were calculated: 57.67% mixture of oils, 19.58% beeswax, and 22.75% cocoa butter. Experimentally designed and optimized lipstick formulation had good physical properties and high scored sensory evaluation. Correlation analysis showed a significant relationship between sensory and instrumental evaluations.

Fractionation and evaluation of proteins in roots of Echinacea purpurea (L.) Moench

Abstract Echinacea purpurea (L.) Moench, a member of the Asteraceae family, is a plant rich in flavonoids, essential oils, phenolic compounds, saponins, polysaccharides and glycoproteins. The aim of the study was to evaluate the protein content in dried roots of Echinacea purpurea (L.) Moench after homogenization of roots with liquid nitrogen, extraction in 0.01 mol L-1 phosphate-buffered saline (PBS) and purification followed by fractionation of proteins using gel filtration chromatography. Total concentration of proteins was measured using the Bradford method, and evaluation of the molecular mass of proteins was accomplished by applying the SDS-PAGE gel electrophoresis. The Bradford assay revealed that the highest concentration of proteins in fractions collected after gel filtration chomatography was 4.66–6.07 mg mL-1. Glycoproteins, alkamides and polysaccharides in roots of Echinacea purpurea (L.) Moench are chemical compounds that are responsible for their immunomodulatory properties. However, information about the difference of protein contents in fresh and dried roots of E. purpurea is insufficient.