ULTRASTRUCTURAL CHANGES OF WOUND MACROPHAGES UNDER THE INFLUENCE OF INTRAVENOUS OZONE THERAPY IN PATIENTS WITH DIABETES AND INFLAMMATORY PROCESSES OF SOFT TISSUES.

Investigation of ultrastructural peculiarities of morpho-functional changes of macrophages have been studied with the purpose of determining the dynamics and thrust of destructive-necrotic processes in these cells when the ischemic-gangrenous form of diabetic foot syndrome develops show what under the influence of intravenous ozone therapy stimulant effect on functional activity and beneficial effect on elimination, mainly due to genetically programmed cell death (apoptosis), playing a significant role in the regulatory mechanisms of the inflammatory process. The stimulation of macrophages functional activity under the influence of ozone, as well as the presence of destructive changes in such cells without necrotizing lesions, is explained by the inclusion of the mechanism of apoptosis as a positive factor in the regulation of local homeostasis at the completion of the inflammatory (exudative) stage of the wound process.

Influence of plant polyphenols and medicinal plant extracts on antibiotic susceptibility of Escherichia coli.

AIMS: To investigate the influence of polyphenols and plant extracts on the susceptibility of Escherichia coli to antibiotics. METHODS AND RESULTS: Susceptibility of E. coli to antibiotics in the presence of extracts and polyphenols was estimated by the determination of the minimum inhibitory concentrations (MICs). To study gene expression, we used strains of E. coli carrying fusions between promoters of genes katG, sodA, iucC and structural ß-galactosidase gene. Treatment with polyphenols and some plant extracts significantly decreased the antibacterial effects of antibiotics, to a larger extent, ciprofloxacin. The most remarkable protective effect was observed for the extracts of Chamerion (Epilobium) angustifolium, Filipendula vulgaris, Tanacetum vulgare and Serratula coronata. These extracts increased the MICs of ciprofloxacin by four and more times. In case of kanamycin, extracts of Artemisia austriaca and Artemisia pontica increased MICs by four and eight times, respectively. Polyphenol quercetin also caused protective effect against ciprofloxacin, increasing the MIC by four times. A positive correlation was found between protective effects of polyphenols and extracts and their antioxidant activity. CONCLUSION: Medicinal plant extracts and polyphenols may protect cells of E. coli against antibiotic toxicity. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study may be used to enhance the efficiency of antibacterial therapies.

Assessment of anti-oxidant activity of plant extracts using microbial test systems.

AIMS: To evaluate the anti-oxidant properties of extracts from 20 medicinal herbs growing in western Siberia using microbial test systems and different in vitro methods. METHODS AND RESULTS: In vivo anti-oxidant activity of extracts was evaluated for their capacity to protect bacteria, Escherichia coli, against bacteriostatic and bactericidal effects of H(2)O(2) and menadione, and action on anti-oxidant gene expression. In vitro anti-oxidant activity has been examined by a number of methods including: the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH(*))-scavenging assay, chelating activity and capacity to protect plasmid DNA against oxidative damage. In addition, total polyphenol content was determined. The extracts of Fragaria vesca, Rosa majalis, Pentaphylloides fruticosa, Alchemilla vulgaris and Pulmonaria mollis possessed the highest levels of anti-oxidant activity in vivo and in vitro. The protective properties were more closely related to the DPPH(*) radical-scavenging activity, tannin content and action on anti-oxidant gene expression than to other parameters. CONCLUSION: The extracts of medicinal plants may have anti-oxidant effects on bacteria simultaneously through several different pathways, including direct inhibition of reactive oxygen species, iron chelation and anti-oxidant genes induction. SIGNIFICANCE AND IMPACT OF THE STUDY: Using microbial test systems, we revealed herbs that may be used as potential sources of natural anti-oxidants.

[The antioxidant characteristics of medicinal plant extracts from Western Siberia].

An antioxidant activity of the water-alcohol extracts of leaves of ten herbs from Western Siberia was studied. In vivo the capability of extracts to protect cells of Escherichia coli against the bacteriostatic action of H2O2 and the influence of the extracts on the expression of the antioxidant gene katG coding catalase-hydroperoxidase I were investigated. In vitro the radical-binding activity with DPhPG (1,1-diphenyl-2-picrylhydrazyl radical), the chelating capability with ferrozine, and total composition of flavonoids and tannins were determined. The extracts of Filipendula stepposa and Limonium gmelinii were characterized by the highest antioxidant activity. According to data, the test extracts could have an antioxidant effect on bacteria in different ways at once including the direct inhibition of ROS (reactive oxygen species), iron ion chelation and antioxidant gene induction.

Effects of penetrating and non-penetrating oxidants on Escherichia coli.

Treatment of Escherichia coli K-12 cells aerobically grown in M9 glucose salt medium (H2O2) and non-penetrating (ferricyanide) oxidants resulted in similar inhibition of growth and decrease in intracellular K+ pool by 15%. Only H2O2 inhibited growth of auxotrophic strains grown in M9 medium supplemented with protein hydrolysate. Ferricyanide reduction was associated with decrease in low-molecular-weight thiols, whereas the treatment of cells with H2O2 increased their level. Pretreatment of cells with ferricyanide enhanced the H2O2-induced expression of katG gene encoding for catalase HPI; this gene is a member of the gene family controlled by the oxyR gene. Pretreatment with ferricyanide inhibited H2O2-induced expression of the sfiA gene which is the member of the gene family controlled by the recA and lexA genes. Glutathione is the major low-molecular-weight thiol in E. coli, and it can play different roles in cellular responses to H2O2 and ferricyanide.