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1.
Int J Mol Sci ; 23(21)2022 Oct 23.
Article in English | MEDLINE | ID: mdl-36361558

ABSTRACT

This study attempts to determine whether the increased blood lead concentration affects the posturographic test and to determine the relationship between the parameters of posture stability and selected parameters of oxidative stress. The study population consisted of 268 male employees and was divided into two equal subgroups, depending on the lead content in the blood. A posturographic examination was performed. Concentrations of lead, cadmium, zinc protoporphyrin, selected essential elements, and selected markers of oxidative stress in the blood were tested. Higher blood lead concentrations positively affected the values of the sway results: the field and the mean velocity of the center of the feet pressure in posturography. The absolute value of the proprioception ratio was similar in both subgroups. The content of malondialdehyde shows a statistically significantly higher value in a subgroup with high blood lead concentration and exhibits significant correlations only with some of the posturography parameters. The lipofuscin content in erythrocytes correlates with the results of the posturography test. Zinc protoporphyrin, total oxidant status, total antioxidant capacity, selected minerals, and metals did not correlate with the results of the posturography test. In conclusion, posturographic results correlate only with selected markers of oxidative stress, so it can be assumed that the effect on the body balance is only partial.


Subject(s)
Lead , Posture , Humans , Male , Proprioception , Oxidative Stress , Erythrocytes
2.
Molecules ; 27(21)2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36364305

ABSTRACT

The purpose of the study was to evaluate the impact of the Saccharomyces cerevisiae and S. kudriavzevii mixed culture on the fermentation, chemical and aromatic composition of semi-sweet white wines. The variables tested in the experiment were the initial ratio of yeast in mixed cultures and the time of inoculation of the S. kudriavzevii co-culture. The addition of S. kudriavzevii to the inoculum did not significantly change the chemical composition of the wines obtained. No reduction in ethanol yield was found in mixed culture fermented wines; however, in some variants of the experiment, the ethanol content was higher. The mixed cultures of S. cerevisiae and S. kudriavzevii increased the level of volatile compounds in white grape wines. Wines fermented with the co-culture of S. kudriavzevii were characterized by a more diversified ester profile. The mixed cultures of S. cerevisiae and S. kudriavzevii raised the levels of terpenes in white wines. The most promising results were obtained for mixed culture variants, in which S. kudriavzevii was sequentially inoculated on the sixth day of fermentation.


Subject(s)
Saccharomyces , Wine , Wine/analysis , Saccharomyces cerevisiae , Fermentation , Odorants/analysis , Ethanol/analysis
3.
Foods ; 11(13)2022 Jun 24.
Article in English | MEDLINE | ID: mdl-35804682

ABSTRACT

A new method was proposed to produce alginate bio-films containing Pichia membranifaciens and Wickerhamomyces anomalus killer yeast to control the post-harvest fungal decay in organic apples caused by Botrytis cinerea and Penicillium italicum. Coatings with W. anomalus killer yeast effectively controlled the growth of P. italicum during storage at 22 °C. W. anomalus killer yeast incorporated in alginate reduced the P. italicum incidence from 90% (control) to 35% after 14 days of storage at 22 °C. Alginate biofilms with W. anomalus or P. membranifaciens also limited the incidence of the fungal decay of apples inoculated with B. cinerea compared with the control fruits, although the antagonistic capability against B. cinerea was lower than against P. italicum. The survival of W. anomalus cells in alginate coating was higher than P. membranifaciens. The incorporation of killer yeasts into alginate had no significant effect on the mechanical properties (tensile strength, percent elongation at break) of alginate coating, however, they increased the thickness of the biofilm. The bioactive coating reduced the fruit weight loss and had no significant effects on the fruit firmness during storage at 2 °C. As organic apples, produced without any synthetic fungicides, are especially prone to fungal decay during storage, the proposed alginate biofilms containing killer yeast seem to be a very promising solution by offering non-chemical, biological control of post-harvest pathogens.

4.
J Nutr Biochem ; 106: 109021, 2022 08.
Article in English | MEDLINE | ID: mdl-35472434

ABSTRACT

Weight loss is recommended for obese patients with cardiovascular risk; however, it remains questionable how hyperglycemia affects this process. To address this problem, we aimed to determine the association between weight loss, lipid profile, and body mass parameters in obese normoglycemic and hyperglycemic patients. Obese (body mass index30 kg/m2) normoglycemic and hyperglycemic volunteers were placed on a weight reduction program that included a balanced, low-calorie diet and moderate exercise for 6 months. Participants were assessed for serum glucose, ß-cell functions, insulin resistance, lipid metabolism, lipoprotein profile, and body mass parameters. This weight reduction program fully normalized serum glucose levels only in a subpopulation of patients. These individuals also exhibited a significant reduction in body weight, and significant improvement in serum lipid profile and insulin resistance. In contrast, the patients that remained hyperglycemic were characterized by persistent insulin resistance, increased levels of atherogenic fractions of LDL and HDL lipoproteins, and elevated values of a modified Atherogenic Index of Plasma. Correlation analysis indicated a strong positive association between the modified Atherogenic Index of Plasma with atherogenic lipid profile, insulin resistance, and body mass parameters, indicating its usefulness in clinical studies in obese patients. Overall, our data indicate that successful treatment of hyperglycemia facilitates weight loss and improves the composition of blood lipids, while persisting hyperglycemia negatively affects the weight loss process and maintains an atherogenic lipid profile. Because hyperglycemia predisposes to cardiovascular disorders, its correction should be the primary goal during weight reduction therapy.


Subject(s)
Atherosclerosis , Cardiovascular Diseases , Hyperglycemia , Insulin Resistance , Body Mass Index , Cardiovascular Diseases/etiology , Cardiovascular Diseases/prevention & control , Glucose , Heart Disease Risk Factors , Humans , Hyperglycemia/complications , Insulin Resistance/physiology , Lipids , Obesity/metabolism , Risk Factors , Weight Loss
5.
Article in English | MEDLINE | ID: mdl-35055821

ABSTRACT

The current study is focused on the influence of hyperglycemia on weight loss in obese premenopausal women. Specifically, the study evaluated the impact of a six-month individualized low-calorie diet combined with moderate exercise on weight reduction and glucose metabolism in obese women with normoglycemia compared to obese women with moderate hyperglycemia. The results indicated that patients with normoglycemia achieved a successful weight loss, which was connected to a decrease in adipose tissue and reflected by diminished content of visceral fat area (VFA) and percent body fat. In contrast, weight reduction in patients with hyperglycemia was connected not only to the loss of VFA but also to undesired decrease in skeletal muscle mass as well as intracellular and total body water. These unfavorable outcomes were observed despite normalization of glucose metabolism reflected by statistically significant lowering glucose, fructosamine, advanced glycation end-products, and HOMA-IR levels. Overall, the obtained results indicate the importance of the measurement of the carbohydrate profile in obese women and the need for an early introduction of weight reduction strategies before the development of hyperglycemia.


Subject(s)
Body Composition , Water , Adipose Tissue/metabolism , Body Composition/physiology , Female , Humans , Longitudinal Studies , Muscle, Skeletal/metabolism , Obesity/metabolism , Water/metabolism , Weight Loss/physiology
6.
Article in English | MEDLINE | ID: mdl-30591697

ABSTRACT

Although weight loss is recommended for obese patients, it remains questionable how much weight loss is optimal. A novel index that accurately determines the risk of cardiovascular diseases (CVDs) in terms of weight loss is needed. The modified Atherogenic Index of Plasma (AIP), presented here is unique in the literature. It is calculated based on data for anti-atherogenic, high-density lipoprotein cholesterol (HDL-C) fractions, instead of the total HDL-C. This study investigates whether weight loss correlates with CVD risk, and whether the modified AIP allows more accurate diagnostics in obese/overweight people. According to the increase or decrease of AIP during weight loss, 52 Polish patients were subdivided into two groups: group I (increased AIP; n = 16) and group II (decreased AIP; n = 36). The patients' body mass composition and fasting serum lipid parameters (total cholesterol, triglycerides, HDL-C, and LDL-C (low-density lipoprotein cholesterol)), and cholesterol in 21 lipoprotein sub-fractions were determined. Over six months, all patients reduced their body mass by about 10%. There were no significant differences in anthropometric measures between groups. Increases in large and intermediate HDL-C fractions 1 to 6 and decreases in smaller fractions 7 to 10 were observed in group II. In group I, HDL-C fractions 1 and 10 decreased, while cholesterol in other fractions increased. Increases were observed in the antiatherogenic HDL-C of 52% of group II and 4% of group I. As for atherogenic HDL-C, a decrease of 24% was observed in group II and an increase of 9% in group I. In group I, increases of very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and large LDL fractions were noticed, and the reverse in group II. The results show that the modified AIP is a more accurate indicator of CVD risk than existing indices, and that uncontrolled weight reduction does not necessarily have a beneficial influence, and may adversely affect the cardiovascular system.


Subject(s)
Cardiovascular Diseases/epidemiology , Lipids/blood , Overweight/epidemiology , Overweight/therapy , Weight Loss/physiology , Adult , Atherosclerosis/blood , Atherosclerosis/epidemiology , Biomarkers , Body Composition , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Diet , Exercise , Female , Humans , Male , Middle Aged , Obesity/epidemiology , Obesity/therapy , Poland/epidemiology , Prognosis , Risk Factors , Weight Reduction Programs/methods
7.
J Vet Res ; 62(2): 199-205, 2018 Jun.
Article in English | MEDLINE | ID: mdl-30364903

ABSTRACT

INTRODUCTION: The aim of this study was to investigate whether the type and form of oil (raw/non-oxidised (N) or post-frying/oxidised (O)) consumed in high-fat diets affect the oxidative status of an organism, as observed by malondialdehyde (MDA) concentration as an oxidative factor and antioxidant enzyme activity. MATERIAL AND METHODS: Fats in the diet came from rapeseed oil (R) and olive oil (O). RESULTS: The applied diet caused a decrease in MDA concentration (µmol/L) in serum in group RN from 2.94 ± 0.87 to 1.76 ± 0.13, in group ON from 2.45 ± 0.62 to 1.50 ± 0.10, and in group OO from 2.70 ± 1.16 to 1.84 ± 0.36. Meanwhile, MDA concentration (mmol/L) increased in blood haemolysate in group RO from 0.15 ± 0.07 to 0.22 ± 0.03 and in group OO from 0.17 ± 0.02 to 0.22 ± 0.02. The observed changes caused a response of the enzymatic antioxidant system in both models, especially followed by an increase in activities of total superoxide dismutase and its mitochondrial isoenzyme in all experimental groups, while its cytosolic isoenzyme activity increased only in ON and OO groups. Increased activity of glutathione peroxidase (GPX) in groups RN and RO and of catalase (CAT) in groups ON and OO was observed. Significant differences in responses to the different types and forms of oils were probably caused by the different oxidative stability of the studied oils. CONCLUSION: This diet disturbed the body's oxidative status; however, during the six-month study the enzymatic antioxidant system remained effective.

8.
Med Pr ; 69(4): 403-412, 2018 Aug 20.
Article in Polish | MEDLINE | ID: mdl-30157622

ABSTRACT

BACKGROUND: Fluorine influences many processes occurring in the organism. Controversies over the evaluation of the biological effects of this substance are due to a small difference between tolerable and toxic fluorine doses. One of the main mechanisms of the fluorine toxic action is its ability to induce oxidative stress via reactive oxygen species generation and antioxidant defense system impairment. It is important to evaluate possible interactions between fluorine and other substances that may increase or decrease its toxicity. MATERIAL AND METHODS: The study lasted for 35 days. Twenty-four rats were divided into 4 groups: the control, with sodium fluoride (NaF) in the diet, with sodium fluoride, methionine and vitamin E (NaF+M+E) in the diet, with sodium fluoride and vitamin E (NaF+E) in the diet. The biochemical analysis conducted in animal liver homogenates included determination of activities of: total superoxide dismutase (t-SOD), superoxide dismutase with copper and zinc (CuZnSOD), superoxide dismutase with manganese (MnSOD), glutathione peroxidase (GPX), catalase (CAT), glutathione reductase (GR), glutathione S-transferase (GST) and the malondialdehyde (MDA) concentration. RESULTS: The activities of CuZn- SOD, GPX, CAT and MDA concentration were changed significantly. There were no differences in the activities of t-SOD, MnSOD, GR and GST among the experiment. CONCLUSIONS: In the conducted experiment, the run-out of enzymatic protection of liver by decreasing of the activities of antioxidant enzymes (CAT and GPX) and increasing the MDA concentration in NaF group was observed. The addition of vitamin E and methionine does not significantly stimulate the enzymatic antioxidant system, however, it causes of MDA concentration decreases. Med Pr 2018;69(4):403­412


Subject(s)
Liver/drug effects , Methionine/pharmacology , Oxidative Stress/drug effects , Vitamin E/pharmacology , Animals , Antioxidants/pharmacology , Catalase , Glutathione Peroxidase , Glutathione Reductase , Glutathione Transferase , Liver/enzymology , Liver/metabolism , Male , Rats , Rats, Wistar , Sodium Fluoride/toxicity , Superoxide Dismutase , Superoxide Dismutase-1
9.
Med Pr ; 68(3): 391-399, 2017 May 16.
Article in Polish | MEDLINE | ID: mdl-28512366

ABSTRACT

BACKGROUND: Oils are often fried which reduces their beneficial biological and nutritional properties, contributing to disturbances in homeostasis. Some antioxidant substances can improve stability of oils. The aim of the study was to examine the effect of α-lipoic acid (ALA) on the concentration of sulfhydryl groups, lipid peroxides, malondialdehyde, creatinine and urea in serum of rats fed high fat diet for 3 months. MATERIAL AND METHODS: Thirty six Wistar rats were equally divided into 6 groups: the control group on standard breeding diet (SB), oxidized oil (OU) group on SB with 10% oxidized oil, ALA10 group on SB with ALA 10 mg/kg of body weight (b.w.), OU+ALA10 group on SB with oxidized oil and ALA (10 mg/kg b.w.), ALA50 group on SB with ALA in a dose of 50 mg/kg b.w., OU+ALA50 group on SB with oxidized oil and ALA (50 mg/kg b.w.). Oil was oxidized in 180°C for 6 h. RESULTS: We observed decrease in concentration of protein sulfhydryl (PSH) groups in all study groups except for ALA10 vs. control group (C) and increase in OU+ALA10 and OU+ALA50 vs. OU; increase in the lipid hydroperoxide (LHP) concentration in OU, OU+ALA10 and OU+ALA50 vs. C and decrease in all study groups vs. OU; increase of malondialdehyde (MDA) in OU vs. all other groups. And also increase in creatinine and urea concentration in OU group. CONCLUSIONS: High fat diet rich in oxidized oil intensifies the lipid peroxidation process and oxidation of sulfhydryl groups. It can also impair kidney function. Administration of lipoic acid in a dose of 10 mg/kg b.w. inhibits the lipid peroxidation and protects sulfhydryl groups. Med Pr 2017;68(3):391-399.


Subject(s)
Antioxidants/pharmacology , Diet, High-Fat/adverse effects , Lipid Peroxidation/drug effects , Thioctic Acid/pharmacology , Animals , Creatinine/blood , Free Radicals/blood , Lipid Peroxides/blood , Male , Malondialdehyde/blood , Rats , Rats, Wistar
10.
Biomed Res Int ; 2015: 827879, 2015.
Article in English | MEDLINE | ID: mdl-26634212

ABSTRACT

We hypothesized that addition of substances with antioxidant activity could decrease the concentrations of biomarkers of oxidative stress and inflammatory process, thus inhibiting nonalcoholic steatohepatitis development. We investigated the influence of α-lipoic acid (ALA) and garlic administration on the development of adverse changes in rabbit liver and serum under oxidative stress conditions induced with HFD from oxidized oils. We determined 8-hydroxy-2'-deoxyguanosine (8 OHdG) and malondialdehyde (MDA) in liver homogenates, total oxidant status (TOS), lipid peroxides (LOO) and tumor necrosis factor alpha (TNFα) in blood serum, and TNFα and IL-1α genes expression in liver. The results indicate that the intake of dietary ALA and garlic was significantly associated with decreases of 8 OHdG and MDA levels in rabbits' liver tissue as well as TOS and LOO levels in rabbits' serum. Similarly, TNFα and IL-1α gene expressions were suppressed due to ALA and garlic supplementation. The histopathological analysis confirmed that HFD results in liver disorder leading to steatosis. This adverse effect of HFD was ameliorated by the supplementation of ALA and garlic. The obtained results indicate a beneficial effect of ALA and garlic administration by reducing the oxidative stress intensity and the levels of some proinflammatory cytokines in rabbits fed HFD.


Subject(s)
Garlic/chemistry , Inflammation Mediators/immunology , Inflammation/immunology , Oxidative Stress/immunology , Plant Extracts/administration & dosage , Thioctic Acid/administration & dosage , Administration, Oral , Animals , Antioxidants/administration & dosage , Biomarkers/blood , Cytokines/immunology , Dietary Supplements , Inflammation/chemically induced , Inflammation/prevention & control , Male , Oxidation-Reduction , Plant Oils , Rabbits
11.
FEMS Yeast Res ; 14(5): 729-40, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24750993

ABSTRACT

The aim of this study was to determine the influence of two different Wickerhamomyces anomalus strains, CBS 1982 and CBS 5759, on the chemical composition and sensory characteristics of Gloster apple wines. They were inoculated into unpasteurized as well as pasteurized apple musts together with a S. cerevisiae strain as a mixed culture. Fermentation kinetics, basic enological parameters, antioxidant properties as well as selected polyphenol, volatile compound, and organic acid contents were analyzed during the experiments. Apple wines obtained after spontaneous fermentation were characterized by high volatile acidity, increased concentrations of acetaldehyde, and volatile esters, as well as the lowest amounts of ethyl alcohol and higher alcohols compared with other samples. Addition of 0.05 g L(-1) W. anomalus killer strains to the unpasteurized must significantly changed the fermentation kinetics and chemical composition of apple wines. The value of volatile acidity was highly decreased, while the amount of higher alcohols and titratable acidity increased. Pasteurization of must improved the fermentation efficiency. Higher amounts of polyphenol compounds and lower amounts of malic acid were also detected. Application of W. anomalus strains together with S. cerevisiae yeast as a mixed culture positively influenced the chemical composition and sensory features of produced apple wines.


Subject(s)
Malus/metabolism , Malus/microbiology , Saccharomycetales/metabolism , Wine/analysis , Wine/microbiology , Fermentation , Organic Chemicals/analysis , Saccharomycetales/growth & development
12.
Rocz Panstw Zakl Hig ; 64(3): 165-71, 2013.
Article in English | MEDLINE | ID: mdl-24325082

ABSTRACT

Magnesium (Mg2+) plays a key role in many essential cellular processes such as intermediary metabolism, DNA replication and repair, transporting potassium and calcium ions, cell proliferation together with signalling transduction. Dietary sources rich in magnesium are whole and unrefined grains, seeds, cocoa, nuts, almonds and green leafy vegetables. Hard water is also considered to be an important source of magnesium beneficial to human health. The daily dietary intake of magnesium is however frequently found to be below that recommended in Western countries. Indeed, it is recognised that magnesium deficiency may lead to many disorders of the human body, where for instance magnesium depletion is believed to play an important role in the aetiology of the following; cardiovascular disease (including thrombosis, atherosclerosis, ishaemic heart disease, myocardial infarction, hypertension, arrhythmias and congestive heart failure in human), as well as diabetes mellitus, gastrointestinal (GI) tract disease, liver cirrhosis and diseases of the thyroid and parathyroid glands. Insufficient dietary intake of magnesium may also significantly affect the development and exacerbation ofADHD (Attention Deficit- Hyperactivity Disorder) symptoms in children. The known links between magnesium and carcinogenesis still remain unclear and complex, with conflicting results being reported from many experimental, epidemiological and clinical studies; further knowledge is thus required. Mg2+ ions are enzyme cofactors involved in DNA repair mechanisms that maintain genomic stability and fidelity. Any magnesium deficiencies could thereby cause a dysfunction of these systems to occur leading to DNA mutations. Magnesium deficiency may also be associated with inflammation and increased levels of free radicals where both inflammatory mediators and free radicals so arising could cause oxidative DNA damage and therefore tumour formation. The presented review article now provides a summary discussion of the various research performed concerning the impact that low magnesium intake has on tumour incidence; this includes impairment of magnesium homeostasis frequently observed in tumour cells, the influence of magnesium depletion on the progression of existing tumours and the occurrence of hypo-magnesaemia when patients are treated with certain anticancer drugs.


Subject(s)
Magnesium Deficiency/metabolism , Magnesium/metabolism , Humans , Magnesium Deficiency/complications , Neoplasms/etiology , Neoplasms/metabolism , Recommended Dietary Allowances
13.
Food Chem ; 109(1): 235-42, 2008 Jul 01.
Article in English | MEDLINE | ID: mdl-26054286

ABSTRACT

A method for analysis of six azaarenes (benzo[h]quinoline, benzo[a]acridine, benzo[c]acridine, dibenzo[a,c]acridine, dibenzo[a,j]acridine and dibenzo[a,h]acridine) in thermally treated high-protein food has been described. The clean-up procedure used based on alkaline hydrolysis, tandem solid phase extraction on columns filled with Extrelut - diatomaceous earth and cation exchanger (propyl sulfonic acid), enabled a selective isolation of carcinogenic compounds belonging to benzoacridines and dibenzoacridines from samples of cooked meat and its gravy. The isolated fractions of aza-PAHs were analysed by high-performance liquid chromatography with fluorescence detection. The detection limits for the azaarenes were between 0.0001ng and 0.005ng loaded on column. The recoveries for the four-ring and five-ring azaarenes were from 55% to 67%. Two types of dishes prepared from pork by pan-frying were investigated. Total contents of the benzoacridines and dibenzoacridines determined in cooked meat were 1.57 and 2.50ng/g in collar and chop samples, respectively; their gravies contained 0.34 and 0.59ng of these azaarenes per g of cooked meat.

14.
Biol Trace Elem Res ; 120(1-3): 195-204, 2007.
Article in English | MEDLINE | ID: mdl-17916971

ABSTRACT

Effect of garlic supplementation on blood antioxidant status, lipid peroxidation, and coronary plaque formation process was investigated in oxidized oil-fed rabbits. Eighteen adult male mixed European rabbits were given a balanced diet (21 g% protein, 34 g% fat, 45 g% carbohydrate), which contained isocaloristic addition of nonoxidized or oxidized rapeseed oil in the presence and absence of garlic. The experiment lasted 24 weeks. At the beginning and every 6 weeks, rabbits were weighed, and blood was taken. To evaluate the antioxidant status of the rabbits, erythrocytes malondialdehyde (MDA) concentration, total superoxide dismutase (t-SOD), and glutathione peroxidase (GPX) activations were determined. After the experiment was completed, aortas were dissected for histological examinations. Changes in the contents of the above parameters and histological examinations showed that oxidized rapeseed, oil administered to rabbits, caused the development of atherosclerotic changes and disturbed antioxidant status. The addition of garlic in such diets inhibited atherosclerotic changes in the aorta wall, and it is related to the homeostatic activity of antioxidative enzymes and lipid peroxidation.


Subject(s)
Antioxidants/analysis , Coronary Artery Disease/prevention & control , Erythrocytes/metabolism , Garlic , Animals , Brassica rapa , Fatty Acids, Monounsaturated , Glutathione Peroxidase/blood , Lipid Peroxidation , Male , Malondialdehyde/blood , Oxidation-Reduction , Plant Oils , Rabbits , Rapeseed Oil , Superoxide Dismutase/blood
15.
Biol Trace Elem Res ; 112(2): 169-74, 2006 Aug.
Article in English | MEDLINE | ID: mdl-17028382

ABSTRACT

The aim of the study was examining the effect of fluoride ions and caffeine administration on glucose and urea concentration in blood serum and the activity of protein metabolism enzymes and selected enzymes of the urea cycle in rat liver. The study was carried out using 18 male Sprague-Daowley rats (4.5 mo old). Rats were divided into three groups. Group I received distilled water ad libitum. Group II received 4.9 mg F-/kg body mass/d of sodium fluoride in the water, and group III received sodium fluoride (in the above-mentioned dose) and 3 mg/kg body mass/d of caffeine in the water. After 50 d, the rats were anesthetized with thiopental and fluoride ions, glucose, and urea concentration in blood serum were determined. Also determined were the activities of aspartate aminotransferase, alanine aminotransferase glutamate dehydrogenase, ornithine carbamoylotransferase and arginase in liver homogenates. Liver was taken for pathomorphological examinations. The applied doses of F- (4.9 mg/kg body mass/d) and F- + caffeine (4.9 mg F-/kg body mass/d + 3 mg caffeine/kg body mass/d) resulted in a statistically significant increase of fluoride ion concentration in blood serum, a slight increase of the glucose concentration, and no changes in the concentration of urea in blood serum. This might testify to the absence of kidney lesions for the applied concentrations of F-. No change in the functioning of hepatocytes was observed; however, slight disturbances have been noted in the functioning of the liver, connected with the activation of urea cycle, increase of arginase activity, and accumulation of F- in this organ. There was no observed significant influence of caffeine supplementation on the obtained results.


Subject(s)
Blood Glucose/analysis , Caffeine/pharmacology , Fluorides/blood , Liver/drug effects , Sodium Fluoride/pharmacology , Urea/blood , Alanine Transaminase/metabolism , Animals , Arginase/metabolism , Aspartate Aminotransferases/metabolism , Glutamate Dehydrogenase/metabolism , Liver/enzymology , Male , Ornithine Carbamoyltransferase/metabolism , Rats , Rats, Sprague-Dawley
16.
J Protein Chem ; 22(3): 285-93, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12962328

ABSTRACT

The cyclic AMP receptor protein (CRP) regulates the expression of many genes in Escherichia coli. The protein is a homodimer, and each monomer is folded into two distinct structural domains. In this study, we have used differential scanning calorimetry (DSC) and circular dichroism (CD) to measure the enthalpy change and melting temperature of the apo-CRP and CRP complexes with cAMP or DNA sequences lac, gal, and palindromic ICAP. DSC and CD measurements showed irreversible thermal denaturation process of CRP. Enthalpy of dissociation of the protein-DNA complex, as measured by DSC, depends on the DNA sequence. The thermal transition of the protein in CRP-DNA complexes, measured by CD, indicates that the protein stability in the complex is also DNA sequence-dependent.


Subject(s)
Cyclic AMP Receptor Protein/chemistry , Cyclic AMP Receptor Protein/metabolism , Cyclic AMP/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , DNA/metabolism , Escherichia coli/chemistry , Calorimetry, Differential Scanning , Circular Dichroism , DNA/chemistry , DNA/genetics , Nucleic Acid Denaturation , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Protein Denaturation , Protein Folding , Thermodynamics , Transition Temperature
17.
Eur J Biochem ; 270(7): 1413-23, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12653996

ABSTRACT

cAMP receptor protein (CRP), allosterically activated by cAMP, regulates the expression of several genes in Escherichia coli. As binding of cAMP leads to undefined conformational changes in CRP, we performed a steady-state and time-resolved fluorescence study to show how the binding of the ligand influences the structure and dynamics of the protein. We used CRP mutants containing a single tryptophan residue at position 85 or 13, and fluorescently labeled with 1,5-I-AEDANS attached to Cys178. Binding of cAMP in the CRP-(cAMP)2 complex leads to changes in the Trp13 microenvironment, whereas its binding in the CRP-(cAMP)4 complex alters the surroundings of Trp85. Time-resolved anisotropy measurements indicated that cAMP binding in the CRP-(cAMP)2 complex led to a substantial increase in the rotational mobility of the Trp13 residue. Measurement of fluorescence energy transfer (FRET) between labeled Cys178 and Trp85 showed that the binding of cAMP in the CRP-(cAMP)2 complex caused a substantial increase in FRET efficiency. This indicates a decrease in the distance between the two domains of the protein from 26.6 A in apo-CRP to 18.7 A in the CRP-(cAMP)2 complex. The binding of cAMP in the CRP-(cAMP)4 complex resulted in only a very small increase in FRET efficiency. The average distance between the two domains in CRP-DNA complexes, possessing lac, gal or ICAP sequences, shows an increase, as evidenced by the increase in the average distance between Cys178 and Trp85 to approximately 20 A. The spectral changes observed provide new structural information about the cAMP-induced allosteric activation of the protein.


Subject(s)
Cyclic AMP Receptor Protein/chemistry , Cyclic AMP/chemistry , DNA/chemistry , Escherichia coli Proteins/chemistry , Allosteric Regulation , Cyclic AMP/metabolism , Cyclic AMP Receptor Protein/metabolism , DNA/metabolism , Escherichia coli , Escherichia coli Proteins/metabolism , Fluorescence Polarization , Fluorescence Resonance Energy Transfer , Macromolecular Substances , Models, Molecular , Naphthalenesulfonates/chemistry , Protein Conformation/drug effects , Spectrometry, Fluorescence
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