Thiamine is recognized as a cofactor for many enzymes involved in intermediary metabolism responsible for energy production. Animal model of thiamine deficiency (TD) included direct evaluation of glucose uptake by estimation of 3 H-deoxyglucose transport across red blood cells membranes and β-oxidation of fatty acids in isolated leucocytes. Feeding of animals with the thiamine-deficient diet (0.018 mg/kg diet) for 30 days resulted in disturbances in energy production. The thiamine intake was limited not only by vitamin B1 deficiency in the diet, but also by time-dependent drop of feed consumption by rats fed this diet. At the end of experiment, diet consumption in this group of rats was 52% lower than in the control group. This was accompanied by low glucose uptake by erythrocytes of rats suffering vitamin B1 deficiency for longer time. At the end of experimental period, glucose uptake was over 2 times lower in TD erythrocytes than in control RBC. Such drop of energy production was not compensated by delivery of energy from fatty acid degradation. In leucocytes from TD rats, the β-oxidation was also suppressed. Observed significant decrease of serum insulin from 2.25 ± 0.25 ng/ml (day 0) to 1.94 ± 0.17 ng/ml (day 30) might have significant impact on observed energy production disorders. The results from this study indicate that the thiamine deficiency significantly reduces feed intake and causes modest abnormalities in glucose and fatty acid utilization.
INTRODUCTION Genistein (plant isoflavone) is a well-known anti-cancer drug with estrogenic-like properties. Genistein also regulates sugar and lipid metabolism; thus, it has anti-diabetic properties. The aim of the study was to evaluate in vitro effects of genistein on glucose transport, fatty acids oxidation, activation of PKB, and expression of genes related to insulin pathway in differentiated myoblast C2C12 mouse cell line. MATERIAL AND METHODS Differentiated myoblast C2C12 mouse cell line was used to assess the effects of different genistein concentrations on glucose transport and fatty acids oxidation measured by radioactivity technique, activation of PKB, and expression of selected genes related to insulin signaling pathway (IR-a, IR-b, IRS-1, PKB, GLUT-4, PP2A, SH-PTP2) at the mRNA and protein levels. Cells were incubated with various concentrations of genistein under standard conditions for 0-48 hours. RESULTS Genistein in low concentrations (0.1-1 μM) significantly increased glucose transport and decreased fatty acids oxidation in C2C12 cells after 48 h of incubation. High concentration of genistein (50 μM) had the opposite effect. Genistein stimulated PKB phosphorylation during the first 5-10 minutes of incubation. There was no significant impact on the protein expression of selected genes (IR-a, IR-b, IRS-1, PKB, GLUT-4, PP2A-Ca, ER-a and ER-b) after 48 h treatment. We observed inverse correlation between genistein concentration and the expression of SH-PTP2 protein. Genistein affected the expression pattern of mRNAs for genes related to the insulin pathway, however, not the expression of the encoded proteins. CONCLUSIONS The results of this study showed that depending on the concentration and time of incubation genistein significantly affects glucose and lipid metabolism and at low concentration modifies expression pattern of a few genes in C2C12 cells.
Chromium is considered a trace element which improves glucose tolerance, but mechanism accounting for this insulin-like action is not recognized. The main purpose of this study was to examine the role of reactive oxygen species (ROS) in chromium and insulin stimulated glucose transport using antioxidants. Effect of chromium ions on phosphatases, enzymes involved in inhibition of insulin signaling was also investigated. Experiments were performed in vitro on C2C12 mouse myotubes. ROS level was measured with the use of confocal microscope and 2',7' dichlorodihydrofluorescein diacetate (DCFH-DA). Glucose metabolism was assayed by the measurement of 2-[3H]-deoxyglucose uptake. Cr3+ ions and insulin treatment caused significant increase of ROS formation and also stimulated glucose uptake in C2C12 cells in concentration dependent manner. Antioxidants (L-ascorbic acid and N-acetyl cysteine 100μM) and DPI (diphenyleneiodonium-NADPH oxidase inhibitor, 10μM) abolished insulin- and Cr-inducted glucose transport. Our results confirm the hypothesis that the ROS are integral part of insulin signaling pathway and that the insulin mimetic effect of Cr3+ ions depends on the antioxidant status of the cells. Surprisingly, chromium treatment resulted in increased activity of membrane phosphatases.
Abstract Introduction: The transition period is the most challenging time for dairy cattle, which is characterised not only by negative energy balance but also by fatty tissue mobilisation. Material and Methods: The efficiency of energy pathways, β-oxidation in WBC and glycolysis in RBC (based on deoxyglucose transmembrane transport) were estimated. Insulin in blood plasma was determined using ELISA. Results: After calving and up to one month after delivery, a significant drop in blood plasma level was noticed, simultaneously with a rise in β-oxidation from 18.93 ±3.64 to 30.32 ±5.28 pmol/min/mg protein in WBC. A strong negative correlation between these two indices (r = −0.68) was found. During the period of transition to lactation an increase in glucose cross-membrane transportation from 41.44 ±4.92 to 50.49 ±6.41 μmol/h/g Hb was observed. A strong positive correlation between glucose transportation in RBC and β-oxidation in WBC (r = 0.71) was noticed. These data are in agreement with results of studies on dairy cows using liver slices from dairy cows in late pregnancy and different stages of lactation, in which changes in gene expression were analysed. Conclusion: It seems that measuring fatty acids oxidation and glycolysis using isolated blood cells may be an adequate and relatively simple method for energy state analysis to estimate the state of dairy cow metabolism and animal health.
[b]Introduction[/b]. Prolonged shortages of protein in the diet significantly alter the composition and content of polyunsaturated fatty acids (PUFA) in tissues and body fluids. One of nutritional factors which may reduce negative effects of protein malnutrition might be vitamin B[sub]2[/sub] due to its influence on lipids metabolism. [b]Objective. [/b]The aim of the study was to investigate the influence of low protein (LP) diet enriched with vitamin B[sub]2[/sub] on the content and composition of PUFA in the blood serum of rats treated with dosed physical exercise. [b]Materials and method. [/b]The experiment was carried out for 3 months on 72 growing male Wistar rats divided into 5 groups. Animals were fed ad libitum on a diet with an energy value of 350 kcal/100 g, in which 4.5% of the energy was provided by protein. In the control diet, 20% of the energy was provided by protein. Two groups were fed the diet enriched with vitamin B2. The two groups of tested animals were trained for 5 days a week. [b]Results.[/b] LP diet caused a decrease in α-linolenic acid (ALA) after 30 days, and a decrease in docosahexaenoic acid (DHA) after 60 days of experiment, compared with rats fed the control diet. After 60 and 90 days of the experiment, a significant decrease was noted in arachidonic acid (AA) in serum of trained rats, compared with sedentary rats fed the LP diet. Physical activity increased LA (mainly on day 30), EPA (on day 90) and reduced AA content (on day 90) in serum of rats fed the LP diet. B2 supplementation in the trained LP group did not change the EPA and AA dependence; however, there was a decrease in LA content in comparison to the non-supplemented trained group. [b]Conclusions. [/b] Results of this study suggest that all investigated factors (protein deficiency, physical exercise and supplementation of vitamin B2) have significant impact on PUFA composition of serum in rats.
Chromium III is a trace element that may improve sugar metabolism in diabetes type II patients. However, its molecular mechanism of action is still unclear. The aim of the paper was to evaluate effect of chromium III ions (chloride) and 17-beta estradiol supplementation on expression of proteins (IR-alpha/beta; IRS-1; ER-alpha and ER-beta) and genes related with insulin signaling pathway. The research was performed on differentiated C2C12 cell line. Both chromium III and estradiol addition caused an increase of IR-alpha without the influence on IR-beta level. Microarray analysis revealed that transcriptional profiles of chromium III and estradiol was almost similar. Moreover, only chromium III addition increased the level of both: ER-alpha and ER-beta, which might suggest increasing susceptibility of estradiol in C2C12 cell line. The results confirm the chromium III impact on the insulin signaling pathway via estrogen receptors, however, to fully recognized this process further studies should be performed.
Modern commercial pig farming systems inflict increased stress in animals, which often leads to various negative changes in the gastro-intestinal tract, especially in the case of piglets. Ban of antibiotics, used as growth promoters, has caused a need for alternatives to conventional antimicrobials in swine diets. Use of pre-/or probiotics, organic acids and plant extracts is often recommended, but it seems that zinc oxide and cooper salts, which were traditionally included in high doses to piglets diet, possess the highest efficacy. In commercial conditions feeding piglets with high doses of Zn and/or Cu stimulates piglets daily gain and decreases feed conversion factor. However, as heavy metals Zn and Cu tend to accumulate in soil and cause serious environmental pollution of soil and tap-water. Furthermore, high zinc concentrations (2500÷3000 mg/kg feed) in feed may have an impact on development of antimicrobial resistance, and may regulate the expression of genes that modify piglets' immune response. Therefore, the use of high doses of ZnO and/or Cu salts, as growth promoter, has always been a subject of discussion, and caused different legal status of such treatment in various EU countries. This short review describes current European Food Safety Authority (EFSA) point of view on the use of ZnO in medicated feed. The higher bioavailability of recently introduced new sources or forms of these metals allows for substantial reduction of dietary inclusion rate, which should have a positive outcome for pigs health and the environment.
BACKGROUND:Training-induced oxidative stress can be reduced by α-tocopherol. Adequate intake of α-tocopherol could have health benefits for previously untrained young subjects.OBJECTIVES:The aim of this study was to determine the effects of training and different doses of α-tocopherol on exercise-induced oxidative stress in rat livers.MATERIAL AND METHODS:Young male Wistar rats (n = 40) were randomly divided into eight groups (undergoing training and not undergoing training, given orally administered α-tocopherol doses of 0, 0.5, 1.0 and 4.0 mg). Every day for 10 consecutive days, the rats in the training groups ran for 15 min on a treadmill at 20 m/min to induce oxidative stress. Hepatic oxidative stress was evaluated based on the liver concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and thiobarbituric acid reactive substances (TBARS).RESULTS:The liver concentrations of α-tocopherol were significantly influenced by α-tocopherol doses (p < 0.001) and physical exercise (p < 0.001). The liver concentrations of α-tocopherol increased in response to the highest dose (4 mg/d) of α-tocopherol in the non-training groups. In the training groups, the liver concentrations of α-tocopherol were independent of the dose. The levels of TBARS, a marker of lipid peroxidation, were lowest in the training and non-training rats administered 4.0 mg of α-tocopherol. Physical exercise and α-tocopherol doses significantly influenced TBARS concentrations (p = 0.004, p < 0.05).CONCLUSIONS:The results of this study indicate that running training causes lipids peroxidation and reduces α-tocopherol levels in the liver, but it does not contribute to DNA damage. Increased liver concentrations of α-tocopherol were found to exert a protective effect against oxidative damage induced by endurance training. An adequate intake of α-tocopherol is important for previously untrained young subjects.
The paper presents investigations of the relationship between the biochemical parameters and vital signs in dairy cows. We analyzed the welfare and functioning of a dairy herd using biochemical parameters and vital signs. Life and biochemical parameters were examined. In the model indicators useful for monitoring the herd are: the age of the cows, the number of cows’ lactating, daily amount of received milk, length of lactation period for cows in the herd, the length of inter-calving period for cows, the number of days to effective insemination, the amount of protein in the feed, the level of β-oxidation in leucocytes, glucose transport through red blood cells and plasma insulin. Based on the results the mathematical model was designed allowing the presentation of a cybernetic model of cow’s organism. There was constructed a multi-equation model which determined the relationships between the selected variables describing the state of dairy cows in the herd and variables that characterize their welfare with its statistical verification.
The estimation of acute phase proteins (APP), which are recognized as inflammation markers is a good method for animal health monitoring. Several factors such as obesity, age and sex are also known to modulate APP status. We evaluated the influence of pregnancy and lactation in 65 clinically healthy dairy Holstein-Friesian dairy cows, 2nd÷4th lactation, chosen from 3 different dairy farms located in South West part of Poland. Bovine C-reactive protein (CRP), haptoglobin and fibrinogen were assayed using commercial ELISA kits. The highest values of CRP and haptoglobin were observed in cows during the first month after calving. The highest concentrations of fibrinogen was found in a group of cows prior to expected date of parturition and the level of this protein in blood plasma was decreasing during lactation. The significant differences of analyzed APPs among cows before delivery, during first month after calving and in lactation (1-3 months after delivery) suggested that factors like pregnancy and stage of lactation would have an influence on their concentration.
Verapamil is a L-type voltage gated calcium channels inhibitor (VGCCI), which is a highly prescribed drug used in the treatment of hypertension, angina pectoris, cardiac arrhythmia and cluster headaches. Its common use caused its appearance in water environment. VGCC inhibit epinephrine release and cause many neuro-hormonal changes influencing also fish behavior. Siamese fighting fish was chosen to study the influence of verapamil given to the water on the beginning of experiment in 3 different concentrations of 0 (control), 8 and 160 μg · L-1, on aggressive behavior in these fish. The experimental fish were placed in individual glass containers for 3 weeks and the mirror test was used. The highest concentration led to a significant modulation of fish behavior after 1 week and the lower dose caused statistically significant behavioral changes after 2 weeks of verapamil treatment. Siamese fighting fish males exposed to verapamil had longer latencies to the first chase - 12.6 s (8 μg · L-1 of verapamil) and 18.8 s (160 μg · L-1 of verapamil) compared to 5.6 s in the control group, decreased attack frequency and shorter duration of these attacks. The number of attacks within 10 min was decreased from 38.3 in the control group to 27.1 and 16.1, respectively. Also the total duration of these attacks decreased from 354.8 (control) to 326.4 (decrease statistically insignificant) and to 194.8 s in verapamil treated groups. It was shown, that even relatively low concentrations of verapamil in water may have adverse effects on fish and probably other living organisms.
Bovine mastitis caused by Streptococcus canis is relatively rare. Consequently, many epidemiologic aspects of the infection, including factors that mediate crossing of host species barriers by the pathogen, infectiousness of the microorganism to the mammary gland, and the course of the disease within a herd, are still not elucidated. Therefore, the aim of the present study was to describe results of a 15-mo observation of subclinical Strep. canis mastitis on a dairy farm housing 76 lactating Holstein-Friesian cows. Upon 3 visits to the farm during a period between April 2013 and June 2014, Strep. canis was cultured from milk samples of 17 (22.4% of the herd), 7 (9.6%), and 8 (11.3%) cows, respectively. The isolates obtained were characterized phenotypically by means of the API Strep identification kit (bioMérieux, Marcy l'Etoile, France), as well as genetically by using random amplified polymorphic DNA and macrorestriction analysis of the chromosomal DNA by pulsed-field gel electrophoresis. All strains displayed the same biochemical features, and the molecular methods revealed that the isolates belonged to a single clone or were very closely related. Results of the study indicate that Strep. canis is capable of causing intramammary infections of long duration, behaving in a contagious manner. Because a persistently infected cow may serve as the source of Strep. canis infection for other animals, effective control of this type of udder infection within a herd may require similar measures to those adopted in Streptococcus agalactiae eradication programs.
Introduction. Ouinoa (Chenopodium quinoa Willd.) is a pseudo-cereal that has received increased interest because it is a good source of different nutrients including proteins, vitamins and other biologically active compounds, and especially as functional gluten-free ingredient of human diet. There are also only limited data concerning the concentration of minerals and antioxidants in quinoa seeds and practically no information concerning composition of whole quinoa plant.
Essential trace elements, chromium (Cr+3) as well as selenium (Se+4) and (Se-2) exhibits stimulatory effect on β-oxidation of fatty acids, especially after supplementation with carnitine. Presented results allowed to conclude, that the trace elements ions modify the activity of the transport of fatty acids across the mitochondrial membranes. It seems that the limiting step of this process is the activity of carnitine-palmitoyl transferase-1 (CPT-1), which is responsible for transport of substrate across the external membrane. In this process selenium ions (Se+4) and (Se-2) are more active than chromium (Cr+4). In all studied combinations of ions the activity of carnitine-palmitoyl transferase -2 (CPT-2) remains almost unchanged. Only small stimulatory effect was observed in combination of Cr and Se ions, but in these variants inhibitory effect on CPT-1 occur.
Two varieties of quinoa (Chenopodium quinoa) viz. Olav and Sandoval were cultivated in central Poland. Biomass and concentrations of Ca, Mg, Mn, Zn, Fe, Cu, and Cr (using flame AAS method) were estimated in different parts of plant (stem, leaves, infructescence), during 180 days of vegetation period. Whole green part of quinoa was found to contain higher concentrations of Mg, Mn, Zn, Fe and Cu than whole plant cereals (data known from literature). Estimated mineral concentrations found in quinoa plant were compared with requirement of these elements for cattle. Comparison of mineral composition of different parts of quinoa showed that the concentration of the examined minerals, except for Cu, were highest in leaves followed by infructescence and stem. In case of this metal its highest concentration was observed in infructescence followed by leaves and stem. At the end of the vegetation period participation of infructescence in plant copper content was high and ranged from 57% (Olav var.) to 65% (Sandoval var.). Average Cu content in quinoa plants of the two examined varieties was positively correlated with duration of vegetation period, and its concentration exceeds 10 mg/kg DM, the stipulated dietary requirements for cattle. It is concluded that quinoa could be used for cattle and seems to be a good source of macro and micro-elements like magnesium, manganese, iron, zinc and copper.
INTRODUCTION Diabetes and obesity are diseases characterized by their increasing incidence every year. When comparing with healthy subjects, the serum levels of chromium (Cr) are lowered in these two diseases. Several studies conducted in laboratory animals with experimentally- induced diabetes demonstrated that supplementation with chromium ions (III) decreased glucose concentration in the blood, reduced the probability of atherosclerosis and heart attack, lowered the levels of cholesterol and low density lipoprotein (LDL). The Importance of chromium is actually challenged due to lack of clear manifestations of Cr deficiency in humans and animals. OBJECTIVE The aim of this review was to present current knowledge about Cr its role in the organism and possible mechanisms of its action also in metabolic disorders such as diabetes or obesity. STATE OF KNOWLEDGE In the last decade, Cr was established to be rather a beneficial than essential trace element in mammals, and has gained popularity as a nutritional supplement and a component of many multivitamin/mineral formulations, fortified food and energy drinks. Cr supplements are widespread for diabetes and obesity treatment, despite conflicting reports on its efficacy. It was suggested that Cr shows a beneficial influence upon glucose and lipid disturbances. CONCLUSIONS The recent clinical trials provided evidence both in favor and against the importance of Cr in healthy and ill organisms. Unfortunately, also the molecular mechanism by which chromium affects glucose and lipid metabolism is still unclear. Beneficial effects of diet supplementation with different sources of Cr³⁺ can be potentially explained by rather pharmacological than nutritional effects.
Material & methods. The experiment (90 days) was performed on male Wistar rats divided into six groups fed ad libitum with semi-purified diets. All diets contained 14.7 MJ gross energy/kg (350 kcal/100 g). Two groups were fed the diet containing 20% of energy from protein and the other four groups were fed the diet containing only 4.5% of energy from protein. Two of the four protein-deficient diets were supplemented with riboflavin in the amount of 75 mg/kg diet as fed. Rats of three groups were trained for one hour daily.
Insulin-like growth factor-I is involved in mammary gland development, promoting proliferation and inhibiting apoptosis of mammary epithelial cells (MECs). Mitogenic actions of IGF-I are mainly mediated by the phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway. We have found that in the presence of IGF-I bovine BME-UV1 MECs cultured on reconstituted basement membrane form large spheroids with disrupted polarity and no cavity in the center. These cells showed enhanced phosphorylation of Akt, decreased level of cleaved caspase-3, and sustained proliferative activity throughout the 16-d period of 3-dimensional culture. Inhibition of the PI3K/Akt pathway by a specific inhibitor of PI3K, LY294002, resulted in the restoration of the normal acinar phenotype. However, this effect was noted only when LY294002 was added in the second week of 3-dimensional culture, which corresponded with the time of cell cycle arrest and polarity formation under control conditions. Normal development of acini was also obtained when BME-UV1 cells were treated simultaneously with IGF-I and 17β-estradiol. The addition of 17β-estradiol regulated Akt activation, enabling the subsequent initiation of polarization processes. 17β-Estradiol also increased the level of IGFBP-3 protein in MECs cultured on Matrigel in the presence of IGF-I. The presented results indicate important interactions between signaling pathways activated by estrogen and IGF-I, which regulate alveologenesis in bovine mammary gland.