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Karnozin (β-alanyl-L-histidin) je dipeptid, tvořený aminokyselinou β-alaninem a L-histidinem. Karnozin a obě aminokyseliny se vyskytuji v mozku a kosternim svalstvu vsech obratlovců. Karnozin v buňkach mozkove tkaně chrani intracelularni bilkoviny před jejich poskozenim kyslikovými radikaly, glykaci a tvorbou přicných vazeb mezi jednotlivými řetězci bilkovin. V kosternim svalstvu karnozin snižuje svalovou unavu způsobenou zvýsenou koncentraci kyseliny mlecne, ktera vede k poklesu pH. S rostoucim biologickým věkem klesa koncentrace karnozinu jak v buňkach mozkove tkaně, tak v bilých svalových vlaknech kosterniho svalstva, cimž dochazi k zhorsovani senzorických a kognitivnich funkci a ubytku svaloviny. Tyto degenerativni procesy lze zpomalit konzumaci potravin bohatých na karnozin nebo doplňovanim diety β-alaninem. β-alanin urcuje rychlost tvorby karnozinu a jeho koncentraci v buňkach mozkove a svalove tkaně. Clanek shrnuje soucasne nazory mediciny na roli karnozinu v procesu starnuti lidskeho organismu a významu obohacovani diety β-alaninem.

L-tryptofan je esencialni aminokyselina, kterou clověk ziskava z potravin. V organismu je soucasti řady bilkovin. Kromě teto role je L-tryptofansubstratem pro syntezu serotoninu a dalsich neurotransmiterů v mozku a travicim ustroji. Clanek je přehledem o použiti L-tryptofanu ke zvýsenihladiny serotoninu v mozku a tim ke zlepseni nalady, smyslových schopnosti a socialniho chovani.

U pacientů s roztrousenou sklerozou (RS) se neurologický deficit projevuje sirokým spektrem klinických potiži, vcetně mikcnich dysfunkci. Infekce mocových cest (IMC) zhorsuji kvalitu života pacientů a mohou významně ovlivnit průběh onemocněni. Pilotni, randomizovana a placebem kontrolovana studie ověřila, že sestiměsicni uživani 1,5 g (odpovida 75 g cerstveho plodu) klikvy velkoplode denně mělo vliv na kvalitu života a na možne sniženi rizika onemocněni infekci mocových cest pacientů s RS. Průkaz profylaxe IMC plodem V. macrocarpon vsak vyžaduje rozsahlejsi klinickou studii.

The aim of this double-blind, placebo controlled clinical trial was to assess the effects of a combination of selenium and silymarin in men with lower urinary tract symptoms, benign prostatic hyperplasia and a prostate specific antigen (PSA) ≤2.5ng/ml. The volunteers were randomized to two groups: the first one (n=26) received 240μg selenium (in the form of yeast l-selenomethionine) plus 570mg silymarin daily for 6 months and the second (n=29) received placebo. Outcome measures were changes in the International Prostate Symptom Score (IPSS), bladder volume (V), urinary flow rate, ultrasound estimated postvoid residual urine volume (RV), serum PSA, testosterone and selenium levels, safety clinical biochemistry, hematology and oxidative stress parameters at baseline and on day 180. The results showed statistically significant differences (p

Lower urinary tract symptoms (LUTS) are a common condition in older men. The objective of the present study was to evaluate the efficacy and tolerability of cranberry (Vaccinium macrocarpon) powder in men at risk of prostate disease with LUTS, elevated prostate-specific antigen (PSA), negative prostate biopsy and clinically confirmed chronic non-bacterial prostatitis. Forty-two participants received either 1500 mg of the dried powdered cranberries per d for 6 months (cranberry group;n21) or no cranberry treatment (control group;n21). Physical examination, International Prostate Symptom Score, quality of life (QoL), five-item version of the International Index of Erectile Function (IIEF-5), basic clinical chemistry parameters, haematology, Se, testosterone, PSA (free and total), C-reactive protein (CRP), antioxidant status, transrectal ultrasound prostate volume, urinary flow rate, ultrasound-estimated post-void residual urine volume at baseline, and at 3 and 6 months, and urineex vivoanti-adherence activity were determined in all subjects. In contrast to the control group, patients in the cranberry group had statistically significant improvement in International Prostate Symptom Score, QoL, urination parameters including voiding parameters (rate of urine flow, average flow, total volume and post-void residual urine volume), and lower total PSA level on day 180 of the study. There was no influence on blood testosterone or serum CRP levels. There was no statistically significant improvement in the control group. The results of the present trial are the first firm evidence that cranberries may ameliorate LUTS, independent of benign prostatic hyperplasia or C-reactive protein level.

The plant chemistry and cytotoxic activity of Colchicum baytopiorum CD Brickell (Liliaceae/Colchicaceae), an endemic species growing in Turkey, has been studied for the first time. Nine known alkaloids were isolated and their structures were identified by spectral methods (UV, IR, (1)H-NMR, and ESI/MS), and the presence of three alkaloids, which could not be isolated from the plant, was also detected by LC/MS/MS spectrometry. Phenolic acids were elaborated using LC/MS and 11 phenolic acids were identified. The presence of two flavonoids appeared to be valuable for chemotaxonomic purposes. Guided by the brine shrimp lethality test (BSLT), methanol extracts were tested for cytotoxic activity by colorimetric MTT test on K562 and HL60 cells. Except the seed extract, all methanol extracts showed more cytotoxic activity on HL60 cells (IC(50): 6.5-0.1 microg/mL) than on K562 cells (IC(50):500-44 microg/mL).

Macleaya cordata (Willd.) (Papaveraceae) is used as an active component in the natural feed additive Sangrovit. Sangrovit contains mixture of the intact aerial parts and the fraction of quaternary benzo[c]phenanthridine alkaloids from M. cordata (FQBA). In a 90-day pilot toxicity trial, Sangrovit and the FQBA were tested for safety. Male Wistar rats were fed for 90 days with 100, 7000 or 14000mg of Sangrovit or 600mg of FQBA in 1kg of feed. Body and organ weights, clinical chemistry and hematology markers, oxidative stress parameters, morphological structure of tongue, liver, ileum, kidney and heart samples, and total cytochrome P450 in liver were monitored. The results showed no statistically significant alterations in any parameter between control and treated animals, except for the group treated with 14000ppm Sangrovit that resulted in elevation of reduced glutathione level and superoxide dismutase activity in liver.

The quaternary benzo[c]phenanthridine alkaloid sanguinarine (SG) is the main component of Sangrovit, a natural livestock feed additive. Dihydrosanguinarine (DHSG) has recently been identified as a SG metabolite in rat. The conversion of SG to DHSG is a likely elimination pathway of SG in mammals. This study was conducted to evaluate the toxicity of DHSG in male Wistar rats at concentrations of 100 and 500 ppm DHSG in feed for 90 days (average doses of 14 and 58 mg DHSG/kg body weight/day). No significant alterations in body or organ weights, macroscopic details of organs, histopathology of liver, ileum, kidneys, tongue, heart or gingiva, clinical chemistry or hematology markers in blood in the DHSG-treated animals were found compared to controls. No lymphocyte DNA damage by Comet assay, formation of DNA adducts in liver by 32P-postlabeling, modulation of cytochrome P450 1A1/2 or changes in oxidative stress parameters were found. Thus, repeated dosing of DHSG for 90 days at up to 500 ppm in the diet (i.e. approximately 58 mg/kg/day) showed no evidence of toxicity in contrast to results published in the literature. In parallel, DHSG pharmacokinetics was studied in rat after oral doses 9.1 or 91 mg/kg body weight. The results showed that DHSG undergoes enterohepatic cycling with maximum concentration in plasma at the first or second hour following application. DHSG is cleared from the body relatively quickly (its plasma levels drop to zero after 12 or 18 h, respectively).

Yacon and maca are native Andean crops with growing popularity as food supplements often in combination with other components, e.g. silymarin. There are however no published data on their toxicity and safety in humans. The aim of our randomized placebo-controlled 90-day study was to evaluate the effects of yacon and maca in combination with silymarin on plasma and lipoprotein lipids, serum glucose and safety parameters in patients suffering from the metabolic syndrome. No adverse effects were found in volunteers using silymarin (0.8 g/day), silymarin + yacon (0.8 + 2.4 g/day) and silymarin + maca (0.6 + 0.2 g/day). A moderate AST level and diastolic blood pressure increase was found in volunteers using maca (0.6 g/day). In conclusion, the combination silymarin + yacon appears to be promising as a nutraceutical in the prevention of diseases with a proatherogenic lipoprotein profile and liver steatosis. The effect of maca on AST level and blood pressure must be considered when using high doses of maca powder. This effect could be reversed by supplementation with silymarin.

UNLABELLED The glycaemic index (GI) is a measure of the food power to raise blood glucose (B-glucose) concentration after a meal. For healthy eating, foods with low GI are recommended. However, for many foods in the European Union the GI has not been defined yet. The aims of this prospective open-label study were: (1) to determine the GI of white bread and juicy cereal bars FIT (Usovsko, Czech Republic) by means of the glucometer Optium (Abbott/Medisense); (2) to compare the GI of tested foods determined in the morning and in the evening hours; (3) to compare the GI of tested foods in men and women and (4) to assess the variability of the GI. METHODS To determine the GI, measured portions of food containing 50 g of carbohydrates were eaten by 11 healthy volunteers. B-glucose curves were constructed from B-glucose values at time 0, 15, 30, 45, 60, 60, 120 min after the meal. The GI was calculated by dividing the incremental area under the curve (IAUC) for the tested food by that for the standard food (IAUCS). In each volunteer each food was tested 5 times so that 5 GI's was obtained and the average was calculated. The GI for each tested food was calculated as the mean from the respective average GI's of the 11 volunteers. MS Excel and the statistical program SPSS v. 10.1 were used to analyze the data. RESULTS (1) The mean values of the GI for white bread was 70.3 % and for juicy cereal bars was 101.0 %, as determined in a total of 139 tests in the whole group of 11 volunteers. There was a difference when comparing white bread vs. glucose (p = 0.012) and white bread vs. cereal bars (p = 0.026) but no difference between glucose and cereal bars. (2) There was no significant difference between the GI determined in the morning and in the evening hours either for the total of 139 tests or for the individual tested foods. (3) No significant difference could be seen between the GI in men and women when comparing glucose, cereal bars and white bread. (4) There was a wide variability of GI in all tested foods: the standard deviation of GI for white bread was 30.7 %, for juicy cereal bars 38.0 %. CONCLUSIONS The GI's for white bread and juicy cereal bars were determined. There was no difference either between the GI values determined in the morning vs. the evening hours or between the values in men vs. women. The results show wide variability. An accurate standard method for the determination of GI needs to be defined, carefully used and re-evaluated to enable a comparison of the results with various methods of other working groups.

Sanguinaria canadesis, Chelidonium majus and Macleya cordata have been used for centuries as alternative medicines. Currently the extracts from these medicinal plants are components of veterinary and human phytopreparations, and of oral-hygiene agents. Sanguinarine and chelerythrine (SA/CHE) are biologically active components of these extracts. They display distinct antibacterial and anti-inflammatory properties, but, on the other hand, they have been reported as having adverse effects - genotoxicity and hepatotoxicity. This paper is aimed at evaluation of the effects of daily administration of the extract from Macleya cordata (2 mg and 100 mg in 1 kg feed, sanguinarine:chelerythrine 3:1) in the diet on the health status of swine. After 90-day administration, alkaloids were retained to a different extent in tissues. The highest SA/CHE retention was detected in the gingiva (0.55 microg/g) and liver (0.15 microg/g), no SA/CHE were detected in muscles. Plasma SA levels attained 0.11 microg/ml. Treated animals did not display any results of hematological, biochemical or histological assay different from controls. A (32)P-postlabeling assay proved that no DNA-adducts with SA/CHE were detected in pig livers. We did not observe any symptom linked to epidemic dropsy syndrome often attributed to sanguinarine. In conclusion, an average daily oral dose of alkaloids up to 5 mg per 1 kg animal body weight proved to be safe.

Using the 32P-postlabeling assay, we investigated the ability of quaternary benzo[c]phenanthridine alkaloids, sanguinarine, chelerythrine and fagaronine, to form DNA adducts in vitro. Two enhanced versions of the assay (enrichment by nuclease P1 and 1-butanol extraction) were utilized in the study. Hepatic microsomes of rats pre-treated with beta-naphthoflavone or those of uninduced rats, used as metabolic activators, were incubated in the presence of calf thymus DNA and the alkaloids, with NADPH used as a cofactor. Under these conditions sanguinarine and chelerythrine, but not fagaronine, formed DNA adducts detectable by 32P-postlabeling. DNA adduct formation by both alkaloids was found to be concentration dependent. When analyzing different atomic and bond indices of the C11-C12 bond (ring B) in alkaloid molecules we found that fagaronine behaved differently from sanguinarine and chelerythrine. While sanguinarine and chelerythrine showed a preference for electrophilic attack indicating higher potential to be activated by cytochrome P450, fagaronine exhibited a tendency for nucleophilic attack. Our results demonstrate that sanguinarine and chelerythrine are metabolized by hepatic microsomes to species, which generate DNA adducts.

Chelerythrine, sanguinarine and an alkaloid extract from Macleaya cordata--sanguiritrin--were found to be inhibitors of aminopeptidase A and dipeptidyl peptidase IV, while fagaronine inhibited dipeptidyl peptidase IV only. At 50 microM, chelerythrine, sanguinarine and sanguiritrin inhibited aminopeptidase N by 82%, 82%, 88%, DPP IV by 38%, 62%, 57%, and fagaronine by 34%, respectively. When bovine serum albumin (500 microg/mL) was added, the inhibition of both proteases by quaternary benzo[c]phenanthridine alkaloids (QBA) (50 microM) was significantly diminished. Strong interaction of chelerythrine and sanguinarine with bovine and human serum albumin was proved by electrophoretic determination of their respective conditional binding constants.

Cranberry (Vaccinium macrocarpon) is being studied for use in the prevention of recurrent urinary tract infection (rUTI) where it affects the adhesion Escherichia coli to the uroepithelium. This 6 month, randomized, double-blind, placebo-controlled trial aimed to evaluate whether a daily dose of 500 mg Pacran® could prevent UTI occurrences in sexually active women with a medical history of at least 2 symptomatic UTI in the previous 12 months. Study participants were randomized to the Pacran® or the placebo group and were followed up for 6 months. The intent-to-treat analysis included 176 participants (n=93 in placebo and n=83 in Pacran® group). In the Pacran® group, the proportion of women experiencing at least one UTI was significantly lower than in the placebo group [10.8% versus 25.8%, respectively, p=0.04, with age adjusted 12-month UTI history (p=0.01), age (p=0.73), and age-squared (p=0.05) also included in the model]. There was a similar finding when risk of an E. coli UTI was assessed (p=0.03). Wh...

This work was aimed to investigate the currant oil-induced modulation of antihypercholesterolemic and LDL antioxidant effects of silymarin (SM), the extract from Silybum marianum L. containing silibinin as the main flavonolignan, and of better bioavailable silibinin-phosphatidylcholine complex (SPC) in rats fed on high-cholesterol (HC) high-fat diet. Feeding of rats on HC-diet supplemented with 10 % of currant oil (from Ribes nigrum L.) containing polyunsaturated fatty acids (PUFA, 61.1% of n–6 and 15.4 % of n–3) and lower amounts of saturated (SFA, 7.7%) and monounsaturated (MUFA, 14.3%) fatty acids caused a significant decrease in plasma cholesterol associated with a mild decrease in VLDL-C and an increase in HDL-C, when compared to rats fed on HC-diet with 10 % of lard fat containing low amounts of PUFA (7.7% of n–6 and 0.7 % of n–3) and higher amounts of SFA (42.7%) and MUFA (47.5%). However, currant oil feeding led to the increased oxidizability of LDL. Silymarin, but not SPC, was effective in prevention of development of dietary induced hypercholesterolemia in the both dietary fats with slightly better result in diet containing the currant oil. On the other hand, SPC supressed more effectively than silymarin LDL oxidizability. The results suggest that antihypercholesterolemic effect of SM in rats fed on HCdiet is improved by dietary currant oil, but the currant oil induces an increased oxidizability of LDL. This can be supressed by improvement of bioavailability of silibinin, as shown here for silibinin-phosphatidylcholine complex.

The study objective was to investigate the potential of a beverage containing silymarin and L-arginine to alter basic physiological and urodynamic parameters in 22 normal healthy men aged 38-59 years. The volunteers drank 500 ml/day beverage without silymarin and L-arginine for 10 days followed, after a 7-day washout period, by the beverage with 400mg silymarin and 295 mg L-arginine for 10 days. Blood and urine samples were collected on days 0, 10 and 27. The beverages were well-tolerated with no adverse effects. Most of the biochemical, hematological and urodynamic parameters remained unchanged. Total antioxidant capacity, total level of antioxidants, lipoperoxidation products (malondialdehyde), advanced oxidation products of proteins in plasma and glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase and catalase levels in erythrocytes were not influenced. Serum γ-glutamyl transferase, malondialdehyde level and activity of glutathione S-transferase in erythrocytes were lowered at day 27 and the concentration of total plasma SH-groups was higher on day 10. Using an ex vivo system, we found that silymarin/silybin at 10-100 μM is able to adsorb onto human erythrocytes and the complexes displayed antioxidant properties as studied using ex situ square-wave voltammetry. The trial showed that silymarin in vivo may protect erythrocytes against oxidative damage.

s. PHYTOPHARM 2012 M 110 Obzory po kliniceskoj farmacologii i lekarstvennoj terapii [Reviews of clinical pharmacology and drug therapy] ТОМ 10/2012/2 Transcripts of CYP26B1 were strongly down regulated (-12 to — 20 fold, p < 0.01) in all three groups based on microarray analysis. RT-PCR revealed the down regulation in all groups, however, significantly only in group b, in which the strongest (20-fold) regulation based on the microarray-analysis was found. Also transcripts of retinoid x receptors (RXRA, RXRb) were down regulated (1.6 to — 2.0, p < 0.05) in group A and C based on microarray data. We can report that the gene expression of CYP26B1 and of retinoid ligands is targeted by willow bark, its salicin rich ethanol fraction and imipramine in the peripheral blood of rats, but to a variable extent. further studies are recommended to fully understand the mode of action of willow bark and its constituents on the retinoid acid metabolism for their further systematic development as co-medication in indications with a prevailing low grade inflammation. References: (1) krivospitskaya O et al. Molecular Medicine 2012, March 09. doi 10.2119. (2) Seldenrijk A et al. J Psychosom Res. 2010 Aug; 69 (2):203–10. (3) Ulrich-Merzenich et al. Phytomedicine 2012, 19 (3–4): 322–9. BIOSAFETY ASSESSMENT OF SILYMARIN AND ARGININE COMBINATION IN HEALTHY MEN © Ulrichova Jitka 1, Valentova Katerina , Vidlar Ales , Simanek Vilim 1 Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Hnevotinska 3, olomouc, 77515, Czech Republic Department of Urology, University Hospital, I. P. Pavlova 5, olomouc, 77500, Czech Republic Silymarin (SMN) in milk thistle is used as a heptoprotective against alcohol and drug toxicity. Silymarin is also being investigated for its cancer preventive and cholesterol lowering properties (1). l-arginine (l-Arg), a semi-essential amino acid, is recommended as an immune and vitality enhancer (2) but with some urinary side effects (3). This controlled intervention trial aimed to investigate the effect on metabolic parameters of a beverage containing SMN and l-Arg in 20 healthy men aged 41–59 years. The design of the study is shown in fig. The subjects drank 500 ml/day beverage without SMN and Arg for 10 days followed by the beverage with 400 mg SMN and 295 mg l-Arg for 10 days. blood and urine samples were collected on days 0, 10 and 27. Total antioxidative capacity, plasma/erythrocyt oxidative stress and clinical chemistry safety markers, urination parameters including iPSS, voiding parameters-rate of urine flow (q max ), average flow (q ave ), total volume and postvoid residual volume (RV) parameters were measured. The data suggest that the combination of SMN plus l-Arg alters the antioxidant status of erythrocyte, other clinical markers or urinary parameters were unchanged. Overall, the drink was well-tolerated with no adverse effects. References: (1) kren V, Walterova d. Silybin and silymarin-new effects and applications. biomed Pap Med fac Univ Palacky Olomouc Czech Repub. 2005, 149 (1): 29–41. (2) bescos R, Sureda A, Tur JA, Pons A. The effect of nitric-oxide-related supplements on human performance. Sports Med. 2012, 42 (2): 99–117. (3) Stothers l, laher i, Christ GT. A review of the l-arginine — nitric oxide — guanylate cyclase pathway as a mediator of lower urinary tract physiology and symptoms. Can J Urol. 2003, 10 (5): 1971–80.

Background. Silymarin, a milk thistle flavonolignan mixture, has anti-proliferative and anti-angiogenic activities in xenografts of human prostate cancer (PCa). Low dietary selenium on the other hand has been associated with increased incidence of PCa. The purpose of the current trial was to determine whether a daily administration of a silymarin and selenium (SM-Se) combination for 6 months would alter basic clinical chemistry and oxidative stress markers, and improve the quality of life score (QoL) in men after radical prostatectomy (RP). Methods. Thirty seven participants, 2–3 months after RP, were randomly assigned to receive 570 mg of silymarin and 240 μg of selenium as selenomethionine (n = 19, SM-Se group) or placebo (n = 18, Placebo group) daily for six months. Both groups had similar clinical and demographic characteristics. Physical examination, QoL score, haematology, basic clinical chemistry and oxidative stress markers, selenium and testosterone levels, antioxidant status were evaluated at baseline, at 3 and 6 months. Results. The six months administration of silymarin and selenium improved the QoL score, decreased low density lipoproteins (LDL) and total cholesterol and, increased serum selenium levels. The combination had no effect on blood antioxidant status and no influence on testosterone level. No adverse events were recorded. No improvement was found in the placebo group. Conclusions. The selected combination of silymarin and selenium significantly reduced two markers of lipid metabolism known to be associated with PCa progression, LDL and total cholesterol in the blood of men after RP. This suggests that this combination may be effective in reducing PCa progression.

The quaternary isoquinoline alkaloid, sanguinarine (SG) plays an important role in both traditional and modern medicine, exhibiting a wide range of biological activities. Under physiological conditions, there is an equilibrium between the quaternary cation (SG+) and a pseudobase (SGOH) forms of SG. In the gastrointestinal tract, SG is converted to dihydrosanguinarine (DHSG). All forms exhibit bright fluorescence. However, their spectra overlap, which limited the use of powerful techniques based on fluorescence spectroscopy/microscopy. Our experiments using a combination of steady-state and time-resolved techniques enabled the separation of individual components. The results revealed that (a) the equilibrium constant between SG+ and SGOH is pKa = 8.06, while fluorescence of DHSG exhibited no changes in the pH range 5–12, (b) the SGOH has excitation/emission spectra with maxima at 327/418 nm and excited-state lifetime 3.2 ns, the spectra of the SG+ have maxima at 475/590 nm and excited-state lifetime 2.4 ns. The DHSG spectra have maxima at 327/446 nm and 2-exponential decay with components 4.2 and 2.0 ns, (c) NADH is able to convert SG to DHSG, while there is no apparent interaction between NADH and DHSG. These techniques are applicable for monitoring the SG to DHSG conversion in hepatocytes.

The biological activity of methanolic and aqueous extracts from dehydrated hypocotyls of Lepidium meyenii (Brassicaceae, vernacular name "maca"), was studied on rat hepatocytes and human breast cancer MCF-7 cells. The extracts did not exhibit cytotoxicity in hepatocyte primary cultures up to 10 mg/ml as measured by the MTT viability test, and lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) leakage. Moreover, after 72 h, extracts inhibited LDH and AST leakage from the hepatocytes. When hepatocytes were intoxicated by t-butyl hydroperoxide, neither extract prevented oxidative damage. Both extracts showed weak antioxidant activity in the DPPH radical scavenging test with IC(50) values of 3.46 +/- 0.16 and 0.71 +/- 0.10 mg/ml, for aqueous and methanolic extracts, respectively. Thus, the observed effect on spontaneous enzyme leakage is probably mediated through mechanisms other than antioxidant activity. Both methanolic and aqueous extracts have shown estrogenic activity comparable with that of silymarin in MCF-7 cell line. Maca estrogenicity was exhibited in the range from 100 to 200 mug of extract per ml. The findings in the present study show that maca does not display in vitro hepatotoxicity. In contrast, a slight cytoprotective effect, probably not mediated by antioxidant capacity, was noted. Maca extracts exhibited estrogenic activity comparably to the effect of silymarin in MCF-7 cells.

A double-blind, placebo-controlled clinical trial was performed to investigate the effectiveness of a herbal-based dentifrice in the control of gingivitis. Forty volunteers completed the 84-day study. All subjects were balanced for parameters measured - plaque index (PI), community periodontal index of treatment needs (CPITN) and papillary bleeding index (PBI). The dentifrice was effective in reducing symptoms of gingivitis as evaluated by the CPITN and PBI indexes.

The cyclic voltammetry (CV) was used for the measurement of the plasma total antioxidant capacity from two types of patients. The first one consisted of 29 volunteers (men aged 18-21 years) who were administered placebo or silymarin at a dose of 858 mg/day. After two months of silymarine administration, CV revealed a statistically significant increase in total antioxidant capacity compared to placebo. No statistically significant changes in TBARS, SH-groups, creatininin, urea, and uric acid concentrations were found. The second group under study comprised 49 patients with chronic renal disease during dialysis therapy. After dialysis, CV revealed a decrease of total antioxidant capacity in the plasma, which was equivalent to a decrease in creatinine, urea and uric acid. CV was performed using a system consisting of a working glassy carbon electrode, an auxiliary platinum electrode, and a reference saturated calomel electrode; a linear change of voltage of 200 mV/s was applied. CV is a simple and relatively reliable method for assessment of body antioxidant status. It is also time and cost effective.

SmrIova J., Z. Dvofiak, J. Lata, P. Ditu, M. Machala, L. Blaha, V. ·imanek, J. Ulrichova:Optimisation of Porcine Hepatocyte Cryopreservation by Comparison of Viability and Enzymatic Activity of Fresh and Cryopreserved Cells. Acta Vet. Brno, 2001, 70: 141-147. Cryopreservation of porcine hepatocytes would ensure the accessibility of cells for laboratory use, permit the standardisation of experiments and save lives of animals. Therefore, in this study, we sought the optimal procedure for cryopreservation of porcine hepatocytes for both laboratory and clinical purposes. Hepatocytes were isolated from the liver lobe of a mini-pig by two-step collagenase perfusion. The cells were frozen with 20% foetal calf serum and 15% DMSO in two different media in four different concentrations ranging from 1 × 10 6 cells/ml to 5 × 10 6 cells/ml. For this purpose, 1.8 ml cryotubes and 120 ml Baxter bags were used. Cells were cryopreserved either in a controlled freezer Sylab or step by step in a styro-foam box and stored at -196 °C. The quality of fresh and cryopreserved hepatocytes was assessed by trypan blue exclusion test and by the evaluation of cytochrome P450 isoenzymes and glutathione-S-transferase activities; primary cultures were evaluated morphologically and by MTT test. Cryopreserved hepatocytes did not form the typical monolayer of polygonal cells in primary cultures and remained round, unlike fresh hepatocytes. Lifetime of viable culture was shortened from 7-8 days to 4 days in cryopreserved cells. Viability of fresh cells was 88 ± 2% and decreased to 36-63% in cryopreserved hepatocytes. Enzyme activities of cryopreserved cells were reduced to 60% when compared with fresh hepatocytes. Concentrations of 3 × 106 cells/ml and 5 × 106 cells/ml and controlled freezing gave the best results. The use of Baxter bags was more convenient due to easier manipulation. Freezing media appeared to have no influence. Freezing conditions, MTT test, cytochrome P450, primary cultures

Background: Sanguinarine (SG) has been reported to form DNA adducts in vitro and increase the levels of DNA single strand breaks in the blood and bone marrow of mice treated intraperitoneally with SG. Recently, we showed no genotoxic eff ects of orally administrated 120 mg/kg feed Macleaya cordata extract (a mixture of sanguinarine and chelerythrine) in pigs or rats in 90-day studies. The goal of this paper was to assess the possible genotoxicity of M. cordata extract when included as a dietary admixture to rodents at concentrations providing 600 mg/kg feed and 100, 7000 or 14000 mg/kg feed Sangrovit ® (natural feed additive containing M. cordata extract and powdered M. cordata) in a 90-day pilot study. Methods and Results: The rats consumed ad libitum either the standard diet or the diets containing 367 ppm of sanguinarine and chelerythrine in M. cordata extract, and 5, 330, or 660 ppm of total alkaloids in Sangrovit ® for 90 days. The DNA adducts formation in liver was analyzed by 32 P-postlabeling technique and DNA single strand breaks in lymphocytes were evaluated by Comet assay. The results showed that M. cordata extract and/or Sangrovit ® induced no DNA damage to rat lymphocytes or hepatocytes after 90-days oral administration. Conclusions: Data from the studies described in this paper and the fact that Sangrovit ® given to the rats in our experiments were higher than the recommended dose (50 to 100 mg/kg feed), argue strongly in favour of the use of Sangrovit ® in live stock.

Background: Colchicine has been used to treat gout for centuries. However, owing to its toxicity it displays a variety of side eff ects. The replacement of colchicine by less toxic but still active derivatives would solve this drawback. Aim: The aim of this study was to examine the cytotoxicity of 17 colchicine derivatives. Methods: Primary cultures of human hepatocytes were the model of choice. Prior to testing, we measured the biochemical parameters of liver donors and the toxicological response of the hepatocytes cultures. For toxicity testing, cells were treated for 24 h with tested compounds in concentrations 1–100 μM. We monitored lactate dehydrogenase (LDH) leakage into the medium, mitochondrial activity (MTT test) and secretion of albumin. Results: Our data show that LDH and MTT were less sensitive parameters compared to albumin secretion for monitoring the toxicity of colchicine derivatives. Compounds with lower antimitotic activity displayed lowered toxicity. Conclusion: Since human hepatocytes in culture are quiescent cells, they are not as susceptible to tropolone alkaloids as proliferating cells. Screening for colchicine derivatives with lowered cytotoxicity revealed that 10-O-demethylated compounds might be the substances of choice.