The Relationship of Uremic Toxin Indoxyl Sulfate and Intestinal Elimination Mechanisms in Hemodialysis Patients

INTRODUCTION

High indoxyl sulfate (IS) concentration is a serious problem for patients with CKD increasing the risk of cardiovascular diseases and CKD progression. Thus, the methods of decreasing the toxin concentrations are highly desired. The study aimed to discover the role of selected intestine-related factors on IS concentration.

METHODS

We evaluated the impact of ABCG2 and ABCC2 polymorphisms influencing activity and protein intake by normalized protein catabolic rate. Additionally, we examined the relation of IS and uric acid (UA) that can share common elimination transporters. A monocentric, prospective, open cohort pilot study was performed on 108 patients undergoing dialysis treatment.

RESULTS

The positive effect of residual diuresis on the reduction of IS levels was confirmed (p = 0.005). Also, an increase in IS depending on the dietary protein intake was confirmed (p = 0.040). No significant correlation between ABC gene polymorphisms was observed either, suggesting the negligible role of ABCG2 and ABCC2 in the elimination of IS in small bowel. The significant difference was observed for UA where ABCG2 421C>A (rs72552713) gene polymorphism was higher (505.3 μmol/L) in comparison with a wild-type genotype (360.5 μmol/L).

CONCLUSION

No evidence of bowel elimination pathway via ABCC2 and ABCG2 transporters was found in renal replacement therapy patients.

SLIDE-Novel Approach to Apocrine Sweat Sampling for Lipid Profiling in Healthy Individuals

We designed a concept of 3D-printed attachment with porous glass filter disks—SLIDE (Sweat sampLIng DevicE) for easy sampling of apocrine sweat. By applying advanced mass spectrometry coupled with the liquid chromatography technique, the complex lipid profiles were measured to evaluate the reproducibility and robustness of this novel approach. Moreover, our in-depth statistical evaluation of the data provided an insight into the potential use of apocrine sweat as a novel and diagnostically relevant biofluid for clinical analyses. Data transformation using probabilistic quotient normalization (PQN) significantly improved the analytical characteristics and overcame the ‘sample dilution issue’ of the sampling. The lipidomic content of apocrine sweat from healthy subjects was described in terms of identification and quantitation. A total of 240 lipids across 15 classes were identified. The lipid concentrations varied from 10⁻¹⁰ to 10⁻⁴ mol/L. The most numerous class of lipids were ceramides (n = 61), while the free fatty acids were the most abundant ones (average concentrations of 10⁻⁵ mol/L). The main advantages of apocrine sweat microsampling include: (a) the non-invasiveness of the procedure and (b) the unique feature of apocrine sweat, reflecting metabolome and lipidome of the intracellular space and plasmatic membranes. The SLIDE application as a sampling technique of apocrine sweat brings a promising alternative, including various possibilities in modern clinical practice.

Different Forms of Ursolic Acid and Their Effect on Liver Regeneration

The aim of this study was to determine the effect of natural and encapsulated sources of ursolic acid on liver regeneration. Four ursolate sources were tested. Two forms of ursolic acid encapsulates were combined with cyclodextrins, i.e., gamma-CD (gCD) and beta-CD, and two natural sources were adjusted by homogenization (HAP) and micronization of apple peel using Jonagold apples. All ursolate forms were applied intragastrically in daily doses of 20 mg for 7 days. Laboratory rats were fed with standard laboratory diet. Further, gCD and MAP were also tested with a high-fat diet (6 weeks). Partial hepatectomy (PH) was performed 24 hours before the end of the experiment. The concentration of plasma hepatocyte growth factor (HGF) was determined with an immunoassay; simultaneously, the expression of HGF and CYP7A1 in the liver was quantified through qPCR. HGF expression and plasma levels were significantly increased 24 hours after PH in both the HAP (p=0.038) and HFgCD groups (p=0.036), respectively. The correlation between HGF expression and plasma values was significant (p=0.04). The positive effects on liver regeneration were found in both the gCD and HAP forms of ursolic acid, whose effects were confirmed through the upregulation of HGF.

Electrolyte and water disorders in old age

Changes in the volume and composition of body fluids are among the essential and limiting parameters both in health and illness. These parameters gain in importance with increasing age. Within the concept of a geriatric patient, disturbances in water and mineral metabolism are the cause of circulatory collapse, stroke, and further instability, falls and delirium. The body can, in the broad range of balance within internal environment, compensate for variations, however always for a limited length of time only, and this compensation ability decreases in particular in older age. Maintaining of water and mineral balance in the elderly is also complicated by polymorbidity. Frequent occurrence of cardiovascular diseases and decline in renal functions later in life results in reduced compensation abilities, which status must be rigorously considered. Besides polymorbidity, also polypragmasia in pharmacotherapy is very frequently encountered in relation to age-related disorders of water and electrolyte handling. Treatment with sedatives also suppresses the feeling of thirst, which results in rapid development of disturbances in water and mineral balance even after small insults, such as feverish illnesses and minor injuries. The knowledge of differences in diagnosing and treatment of water and ion imbalances in later life is becoming increasingly important, espe-cially with regard to the increasing share of older people in society. Key words: ageing - dehydration - electrolyte metabolism - mineral disorders.

Omentin-1 plasma levels and cholesterol metabolism in obese patients with diabetes mellitus type 1: impact of weight reduction

Background:

Omentin-1 is an anti-inflammatory adipokine produced preferentially by visceral adipose tissue. Plasma levels of omentin-1 are decreased in obesity and other insulin-resistant states. Insulin resistance contributes to the changes of cholesterol synthesis and absorption as well. The aim of this study was to characterise omentin-1 plasma levels in obese patients with diabetes mellitus type 1 during weight reduction, and to elucidate the relationship between cholesterol metabolism and omentin-1.

Methods:

Plasma levels of omentin-1 were measured in obese type 1 diabetics (n=14, body mass index >30 kg m⁻², age 29–62 years) by enzyme-linked immunosorbent assay (BioVendor). Gas chromatography with flame ionisation detector (Fisons Plc.,) was used to measure squalene and non-cholesterol sterols—markers of cholesterol synthesis and absorption (phase I). Measurements were repeated after 1 month (phase II; 1 week of fasting in the hospital setting and 3 weeks on a diet containing 150 g saccharides per day) and after 1 year (phase III) on a diet with 225 g saccharides per day.

Results:

Omentin-1 plasma levels were stable during phases I and II, but significantly increased (P<0.001) during phase III. Omentin-1 plasma dynamics were significantly associated with plasma levels of high-density lipoprotein (P=0.005) and triacylglycerols (P=0.01), as well as with lathosterol (P=0.03).

Conclusion:

Omentin-1 plasma levels significantly increased during the weight reduction programme. Omentin-1 plasma dynamics suggest a close relationship with cholesterol metabolism.

Intestinal permeability in patients with metastatic colon cancer treated with patupilone

BACKGROUND

Only a limited number of cytotoxic drugs have shown activity in metastatic colorectal carcinoma. Patupilone is a novel agent with promising activity in this common cancer. Diarrhea represents the dose-limiting toxicity of patupilone. Measurement of intestinal permeability is one of the potential methods of non-invasive laboratory assessment of gastrointestinal toxicity.

METHODS

We have assessed intestinal permeability by measuring absorption of lactulose, mannitol and xylose in 27 previously treated patients with metastatic colorectal cancer enrolled in a phase I trial of patupilone.

RESULTS

Lactulose/mannitol and lactulose/xylose ratios increased after the treatment. Significantly higher lactulose/mannitol ratio was observed in patients who had severe diarrhea. Moreover, patients who subsequently had an adverse event of grade 3 or higher had significantly higher baseline lactulose/mannitol or lactulose/xylose ratios.

CONCLUSIONS

Measurement of intestinal permeability using the lactulose/mannitol test may represent a biomarker for the monitoring, or even prediction of toxicity of cytotoxic drugs, including patupilone.

[Pharmaconutrition in intensive and perioperative care]

The review article covers specific methods of artificial nutrition in current advances in intensive care. This area of care is somewhat specific, and indications for pharmaconutrients are different from classical artificial nutrition. The pharmaconutrients of amino acid and polyenoic fatty acid groups are described. The components of nutritional pharmacology, based on exceedingly high doses of pure nutritional substrates, are a useful and safe means of modifying selected mechanisms, such as fluidocoagulation, inflammatory reactions or vasomotorics.

Disease specific substrates in cancer cachexia - Reality and anticipation

In recent years, the concept of nutrition in patients with tumour diseases has been changing very significantly. The article discusses the pathogenesis of tumour cachexia and sarcopenia, which have been intensively studied, particularly in the last ten years. The possibilities and modern approaches in nutritional support in oncology are reviewed with a special emphasis on the group of elderly patients. Also, a detailed list of the most frequently used pharmaconutrients in oncology is presented. The recommendations for nutritional care of elderly oncological patients are given and discussed.

Gastroduodenal, intestinal and colonic permeability during anticancer therapy

BACKGROUND/AIMS

Measurement of the permeability of gut mucosa may offer a method for objective assessment of mucosal dysfunction during cancer therapy.

METHODOLOGY

Gastroduodenal, intestinal and colonic permeability was studied by using capillary gas chromatography and measuring urinary sucralose, sucrose, lactulose, xylose and mannitol levels. A total of 41 patients with metastatic colorectal carcinoma or epithelial ovarian carcinoma were studied before and during chemotherapy with the combinations of cetuximab, irinotecan, 5-fluorouracil and leucovorin; bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin; or paclitaxel/ platinum.

RESULTS

Compared to pretreatment values, a significant increase was observed during the first cycle of therapy in the percentage of sucrose, sucrose/mannitol ratio, lactulose and lactulose/ mannitol ratio in patients treated with the combination of bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin. No changes were observed in patients treated with cetuximab, irinotecan, 5-fluorouracil and leucovorin, but these patients had significantly higher baseline percentage of lactulose excretion and sucrose/mannitol and lactulose/ mannitol ratios.

CONCLUSIONS

An increase in gastroduodenal and intestinal permeability was observed in patients treated with bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin, but not in patients treated with cetuximab, irinotecan, 5-fluorouracil and leucovorin. No significant increase in colonic permeability was observed, but the present method was insufficient to detect colonic permeability in a significant proportion of patients.

[Advances in metabolism and nutrition 2011 and the route to personalized treatment]

Current model of metabolic and nutritional disorders management utilizes modern techniques that promote some of the nutritional techniques to pharmacoteherapy. This approach is demonstrated on an example of multiple organ failure and systemic inflammatory reaction managed with pharmacologically active nutritional substrates, such as arginine, glutamine, taurine, threonine and cysteine. Treatment of sarcopenia in older age is also discussed. Personalized nourishment as a component part of a wider term personalized medicine represents a new approach that requires recognition of individual differences in human genome and its expression. However, this approach also requires a change of attitude towards laboratory diagnostics and clinical practice, with patients and clinical prediction as the focal point. From this perspective, there is a need to replace current traditional laboratory tests with a new system that utilizes molecular biology and bioinformatics.

Application of the comet assay method in clinical studies

The comet assay or single-cell gel electrophoresis (SCGE) assay is now widely accepted as a standard method for assessing DNA damage in individual cells. It finds use in a broad variety of applications including human biomonitoring, genotoxicology, ecological monitoring and as a tool for investigation of DNA damage and repair in different cell types in response to a range of DNA-damaging agents. The comet assay should be eminently suitable for use in clinical practice since it is a relatively simple and inexpensive technique which requires only a few cells, and results can be obtained within a matter of hours. This method can be used in the study of cancer as well as in lifestyle and dietary studies. In cancer it is useful for measuring DNA damage before, throughout and after therapy (either radiotherapy or chemotherapy). Another use of this method is in lifestyle study, such as investigation of the effect on DNA of common human activities (e.g. smoking, or working with a potentially genotoxic agent). The final use of comet assay in this paper is dietary study. In this type of study we observe the effects of consumption of specific foods or supplements which may be protective for DNA against damage.

[Disturbance of synthesis of cholesterol and its precursors in clinically serious conditions]

OBJECTIVE

The aim of the study was to elucidate the role and importance of hypocholesterolemia in clinically serious conditions. It was a monocentric, prospective clinical study.

MATERIAL AND METHODS

Two groups of patients were recruited to the study--one group were patients with coronary heart disease (CHD), who underwent miniinvasive cardiosurgical operation without extracorporeal circulatio (n = 17) and one group of patients, who sustain polytrauma (n = 19). Thirty six patients were recruited into the study. We performed the determination of sterols (total cholesterol, HDL-cholesterol, LDL-cholesterol, triacylglycerols), and their precursors (beta-sitosterol, campesterol, lathosterol, skvalen), interleukin IL-6 and cortisol in the blood serum. The short version of ACTH stimulation test was performed. The oxidative burst of granulocytes was evaluated. The blood samples were taken on the day of admission, the first, the fourth and the eighth post-operative and post-traumatic day.

RESULTS

There was a significant decline of total cholesterol (TC) and LDL-cholesterol level with full recovery during observed period. There was a decline of cholesterol synthesis (lathosterol and lathosterol/cholesterol ratio) together with a decline of total cholesterol. There was a significantly negative correlation between IL-6 level and total cholesterol. Despite no confirmation of disturbance of adrenal function, there was a significantly positive correlation between lathosterol/cholesterol ratio (a de novo cholesterol synthesis marker) and cortisol level after the ACTH stimulation test. There was a significant breakdown of bactericidal function of granulocytes along with a decline of cholesterol level.

CONCLUSION

There was decline of endogenous cholesterol synthesis in clinically serious conditions. The cholesterol synthesis rate is negatively influenced by IL-6 level. The rate of endogenous cholesterol synthesis positively correlated with cortisol production by the adrenals and with bactericidal function of granulocytes.

The energetic and metabolic effect of Ringerfundin (B. Braun) infusion and comparison with Plasma-Lyte (Baxter) in healthy volunteers

Measurement of parameters of energy requirement, respiratory quotient (RQ), rate of oxygen consumption (VO2) and rate of carbon dioxide production (VCO2) reveal Ringerfundin as an excellent and metabolically stable-acting balanced ionic solution, which does not increase the consumption of O2 or the total energy requirement. In conclusion, Ringerfundin was very well tolerated and in no case were observed undesirable effects.

Antioxidants and vitamins in clinical conditions

Various reactive oxygen species (ROS) may be produced from normal biochemical, essential metabolic processes or from external sources as exposure to a variety of agents presented in the environment. Lipids, proteins, carbohydrates and DNA are all capable of reacting with ROS and can be implicated in etiology of various human disorders (rheumatoid arthritis, reperfusion injury, atherosclerosis, lung diseases etc.). In the organism damage by ROS is counteracted with natural antioxidants (glutathione peroxidases, superoxide dismutases, catalase, glutathione, ubiquinol, uric acid, and essential minerals) and nutritional antioxidants from diet (i.e. vitamins E, C, carotenoids). Possible mechanisms of nutritional depletion and side effects of high intake are in the article described.

[Functional foodstuffs and diabetes--evidence and myths]

Functional food and nutritional supplements balance the difference between the natural nutritional requirement of man, as a slowly changing genotype, and the nutrition of today's man. This type of specifically treated food enables the nutrition of both the healthy population, where functional food eliminates certain risks and have a preventative effect (fibre, microelements), and the nutrition of the ill, which is based on the therapeutical and regulatory effect of nutrients (organ-specific nutrition).

Gastrointestinal permeability in ovarian cancer and breast cancer patients treated with paclitaxel and platinum

Background

Combination of platinum derivatives with paclitaxel is currently the standard front line regimen for patients with epithelial ovarian carcinoma, and represents also an active regimen in patients with metastatic breast or unknown primary carcinomas. Measurement of intestinal permeability represents one of the potential methods of noninvasive laboratory assessment of gastrointestinal mucositis induced by chemotherapy, but little is known about intestinal permeability in patients treated with paclitaxel or platinum.

Methods

Intestinal permeability was assessed in 36 breast and ovarian cancer patients treated with paclitaxel/platinum combination by measuring, using capillary gas chromatography, urinary sucrose, lactulose, xylose and mannitol after oral challenge. The significance of differences during the therapy compared to pre-treatment values was studied by Wilcoxon paired test. The differences between groups of patient were studied by Mann-Whitney U test. Fisher exact test was used to compare the frequency in different subgroups.

Results

After administration of the first dose, a significant (p < 0.05) decrease in xylose absorption and increased lactulose/mannitol, sucrose/mannitol, lactulose/xylose and sucrose/xylose ratios were observed, but these parameters returned subsequently to pre-treatment levels. Patients who experienced serious (grade 3 or 4) toxicity had at baseline significantly lower percentages of xylose, mannitol and sucrose, and higher lactulose/mannitol ratio. Nine of 13 (69%) patients with baseline lactulose/mannitol ratio 0.070 or above experienced serious toxicity compared to 4 out of 23 patients (17%) with the ratio below 0.070 (p = 0.002). Post-treatment lactulose, lactulose/mannitol, sucrose/mannitol and lactulose/xylose ratios were significantly increased in patients with serious toxicity.

Conclusion

A transient significant increase in lactulose/monosaccharide and sucrose/monosaccharide ratios was observed in ovarian and breast cancer patients treated with paclitaxel and platinum. Increased lactulose absorption, lactulose/mannitol, sucrose/mannitol and lactulose/xylose ratios were evident in patients with grade 3 or 4 toxicity, and increased baseline lactulose/mannitol ratio predicted serious toxicity.

Polyunsaturated fatty acids, phytosterols and cholesterol metabolism in the Mediterranean diet

The objective of this work was to review nutritional components of the Mediterranean diet. The Mediterranean diet is not a specific diet plan or diet program but a collection of eating habits that are traditionally followed by the people of the Mediterranean region. There are at least 16 countries bordering the Mediterranean Sea and food habits vary between these countries according to culture, ethnic background and religion. The Mediterranean diet, containing olive oil, fish, fruits and vegetable is associated with a low rate of cardivascular and cancer diseases. This diet is rich in phytosterols, squalene, dietary fibre, antioxidants, phenolic substances and polyunsaturated acids.

Effect of atorvastatin on non-cholesterol sterols in patients with type 2 diabetes mellitus and cardiovascular disease

An increased risk of cardiovascular morbidity and mortality in diabetes mellitus type 2 has been associated with disturbances of lipid homeostasis. Recently, decreased intestinal absorption of cholesterol and increased liver cholesterol production have been reported. To investigate the influence of cholesterol lowering therapy using statin on cholesterol turnover in diabetes mellitus type 2, the levels of non-cholesterol based sterols were studied. One hundred and thirty five patients with type 2 diabetes and non-diabetic controls with cardiovascular diseases were studied. Both groups were divided into two subgroups: treated with atorvastatin and without statin therapy. The diabetics showed significantly higher levels of lathosterol (6.97micromol l(-1) versus 5.11micromol l(-1), p = 0.012) and lower levels of sitosterol (5.03micromol l(-1) versus 8.98micromol l(-1), p < 0.001) and campesterol (6.35micromol l(-1) versus 9.80micromol l(-1), p < 0.001). Non-diabetics showed no significant differences in non-cholesterol based sterols in relation to atorvastatin therapy. A significantly lower level of lathosterol as well as a decrease in lathosterol/cholesterol ratio in the statin treated groups was found in diabetics (4.11micromol l(-1) versus 7.83micromol l(-1), p < 0.001). The results based on ANOVA analysis show that the effect of atorvastatin on the lathosterol level is more pronounced in diabetics. Regression analysis showed the relationship between increased triglycerides levels and the increase in cholesterol synthesis. The calculated regression model for loglathosterol in diabetics has the following form: log(lathosterol) = 2.76 - 0.52.statin + 0.22.cholesterol (ANOVA, p < 0.001, R(2) = 34%, p = 0.005 for statin, p < 0.001 for cholesterol). We conclude that in spite the total cholesterol level in diabetics type 2 is not increased, its endogenous synthesis is enhanced. Our results show that the diabetics type 2 with increased serum lathosterol and expressed metabolic syndrome (mild increase of triglycerides) might represent a suitable group for intensive treatment with statins.

A simple, optimized method for the determination of sulphide in whole blood by GC-mS as a marker of bowel fermentation processes

Hydrogen sulphide is produced in human large intestine by anaerobic fermentation and may play a pathogenic role. An analytical method for determination of sulphide in whole blood using an extractive alkylation technique was optimised and validated for this purpose. The sample was mixed with organic phase containing pentafluorobenzyl bromide as an alkylating agent. The benzalkonium chloride was used as a phase-transfer catalyst. The quantitative determination was performed using GC-MS technique in selected ion monitoring mode. The blood levels of sulphide of healthy controls were measured (35-80 microM/l). The method is versatile, reproducible (RSD=2.7%) and suitable for research of anaerobic fermentation in vivo.