The gut microbiota, its relationship to the immune system, and possibilities of its modulation.

Research of the gut microbiota allows a better understanding of its composition and function and reveals the links between changes in the composition of bacteria and various intestinal but also systemic diseases. The gut microbiota performs several of important functions in the host body and influences many physiological processes. Gut bacteria synthesize many compounds needed for the proper function of the body (e.g., vitamins, short-chain fatty acids, and amino acids). They help maintain the integrity of the intestinal barrier and protect against pathogens. The gut microbiota plays a crucial role in the development and function of the immune system. Significant changes in the composition of the intestinal microbiota led to a dysbiotic state and the loss of its beneficial functions for humans. The review article summarizes the basic knowledge about the composition and function of the bacterial gut microbiota in healthy people, its role in the development of the immune system, and the mechanisms involved in maintaining homeostasis. It also presents current knowledge about the possibility of targeted modulation of the bacterial gut microbiota and faecal transplantation.

Incidence and Prognostic Value of Known Genetic Aberrations in Patients with Acute Myeloid Leukemia--a Two Year Study.

BACKGROUND: In this work, we evaluated the incidence and prognostic value of several genetic aberrations in patients with a diagnosis of acute myeloid leukemia (AML). PATIENTS AND METHODS: We analysed 90 patients: 42 males (mean age 54.5 years) and 48 females (mean age 59 years), with AML. The genetics of all leukemia samples was studied using conventional cytogenetics, the interphase fluorescence in situ hybridisation as well as the standardized RTPCR protocol. RESULTS: In 34.4% of patients, we detected at least one of the analysed genetic aberrations, except the CBFB MYH11, which we did not detect. Translocation t(8;21)/ AML1 ETO was found in 4.4% of patients with a mean age of 45.4 years, while none of these patients was older than 55 years. Translocation t(15;17)/ PMLRARA was found in 5.5% of patients with a mean age of 52.6 years and an almost equal distribution between younger and older patients. The MLL gene rearrangements were found in 6.6% of patients, the -5/ 5q- and/ or -7/ 7q- aberrations in 7.7% of patients, while the most frequent genetic abnormality in our study was trisomy 8 (10%). Moreover, we found a favorable clinical outcome in patients expressing fusion genes AML1-ETO or PMLRARA in contrast to an adverse clinical outcome with few remissions and death in AML patients with MLL, -5q/ -5 and -7q/ 7-. Finally, an intermediate prognosis was found in patients with trisomy 8. CONCLUSION: In this study, we found a good congruence with published literature on the incidence and prognostic value of several well established AML-associated genetic aberrations. This simple genetic-based classification system helps us to identify patients with a favorable, intermediate or unfavorable prognosis and to treat them with the best currently available therapy. However, analysis of new genetically defined abnormalities in AML is necessary for development of better therapeutic strategies and/or diagnostics.

Potential application of body fluids autofluorescence in the non-invasive diagnosis of endometrial cancer.

BACKGROUND: Endometrial carcinoma (EC) is the most common cancer of the female reproductive tract in developed countries. The prognosis and 5-year survival rates are closely tied to the stage diagnosis. Current routine diagnostic methods of EC are either lacking specificity or are uncomfortable, invasive and painful for the patient. As of now, the gold diagnostic standard is endometrial biopsy. Early and non-invasive diagnosis of EC requires the identification of new biomarkers of disease and a screening test applicable to routine laboratory diagnostics. The application of untargeted metabolomics combined with artificial intelligence and biostatistics tools has the potential to qualitatively and quantitatively represent the metabolome, but its introduction into routine diagnostics is currently unrealistic due to the financial, time and interpretation challenges. Fluorescence spectral analysis of body fluids utilizes autofluorescence of certain metabolites to define the composition of the metabolome under physiological conditions. PURPOSE: This review highlights the potential of fluorescence spectroscopy in the early detection of EC. Data obtained by three-dimensional fluorescence spectroscopy define the quantitative and qualitative composition of the complex fluorescent metabolome and are useful for identifying biochemical metabolic changes associated with endometrial carcinogenesis. Autofluorescence of biological fluids has the prospect of providing new molecular markers of EC. By integrating machine learning and artificial intelligence algorithms in the data analysis of the fluorescent metabolome, this technique has great potential to be implemented in routine laboratory diagnostics.

Hypoxia factors suppression effect on the energy metabolism of a malignant melanoma cell SK-MEL-30.

OBJECTIVE: Malignant melanoma (MM), as well as other cancers, is a disorder in the cell life cycle at many levels. In terms of energy, the sync of cytosolic and mitochondrial metabolism is required for each cell. Mismatches also caused by hypoxic factors accumulate defects leading to the formation, development and invasiveness of malignant melanoma. Our aim was to compare the effect of HIF-1α and miR-210 on the metabolism of malignant melanoma cells in normoxia and pseudohypoxia. Further, we also investigated how gene silencing affects the viability in order to evaluate the potential of gene therapy in the treatment of MM. MATERIALS AND METHODS: We targeted oxidative phosphorylation by genetically suppressing HIF-1α and miR-210. We have examined mitochondrial activity, cytosolic glycolysis and cell viability. RESULTS: The ratio of NADH/NAD+ in the cytoplasm under normal conditions is stable and can thus serve as a specific cellular metabolic marker. Therefore, the study was aimed at finding the cause of the reduction in NADH levels in increasing hypoxia under ideal in vitro conditions on the SK-MEL-30 malignant melanoma cells. The relationship between HIF-1α and miR-210, their effect on transcriptional level, and the subsequent effect on metabolic process attenuation in cells was investigated. Obtained results indicate that the NADH which is accumulated by cells in hypoxia was significantly decreased upon gene silencing. CONCLUSIONS: Our studies have shown that small regulatory molecules with organelle-specific effect (such as miRs) need to be targeted, and that the resultant effect is comparable to silencing of "general" hypoxic transcription factors.

Induction of single strand DNA breaks in workers professionally exposed to polycyclic aromatic hydrocarbons.

An epidemiological study was performed on 42 workers from coke works with the aim to evaluate the usefulness of monitoring single strand DNA breaks (SSBs) in human lymphocytes to assess exposure to polycyclic aromatic hydrocarbons (PAHs) as well as the usefulness of SSBs induction as an indicator of biological effects of PAHs. SSBs can be readily quantitated by a simple fluorometric assay of DNA unwinding. Compared with the control group, statistically significant increase in SSBs was observed in coke oven workers occupationally exposed to PAHs. These findings are in agreement with previous results obtained by a different method of measuring DNA damage in subjects exposed to high PAH levels. The findings confirmed that SSBs determination in human lymphocytes reflected the exposure to PAHs and the FADU method appears to be useful in the revelation of effects of occupational exposure to industrial air pollutants such as PAHs.

Effect of quercetin on daunorubicin-induced heart mitochondria changes in rats.

Cancer therapy with daunorubicin is limited by its cardiotoxicity. It has been suggested that daunorubicin-induced free radical generation can be involved. The precise molecular mechanism of daunorubicin-induced cardiotoxicity is still not well understood but it is believed that mitochondria play an important role in this process. It has been reported that flavonoids with antioxidant properties may prevent anthracycline-induced cardiotoxicity. In this work, we investigated the effects of daunorubicin and quercetin on mitochondrial enzyme activities such as ATPase, glutathione peroxidase (GPx) and glutathione reductase (GR). Moreover, we also studied the changes of outer mitochondrial membrane using synchronous fluorescence spectra. The activity of ATPase and GR were significantly increased after daunorubicin application. Pretreatment with quercetin significantly alleviated this increase. On the other hand, GPx activity was significantly decreased and quercetin prevented this decrease. Treatment with quercetin alone had no significant effect on the enzyme activity studied. Quercetin also completely prevented daunorubicin-induced changes in fluorescence of the outer mitochondrial membrane. In conclusion, our data indicate that quercetin may be useful in mitigating daunorubicin-induced cardiotoxicity.

[Problems and perspectives of wider use of saliva for diagnostic purposes]. / Problémy a perspektívy sirsieho vyuzitia slín na diagnostické úcely.

Saliva of individual salivary glands differs in appearance, density and particularly in the chemical composition. Generally, the composition of saliva is affected by the composition of blood plasma, salivary flow rate, hormonal activity, drug administration, smoking and other physiological and pathophysiological states of the organism. In spite of these facts, many of the components are permanently present in saliva (e.g. peptides, enzymes, hormones...) only their concentrations vary. In some special cases unusual constituents can be detected in the saliva as legal and illegal drugs, antibodies (HIV), and abnormal bacteria or viruses. When there is good correlation between the levels of constituents in saliva and blood plasma then the determination of the constituent level in saliva can be used for diagnostic and/or monitoring purposes. But the main advantage of saliva analysis resides in stress-free and harmless collection of saliva in comparison with blood withdrawing. However, the use of saliva for diagnostic purposes is still at its beginning. So far, only few such applications are known, but optimists believe that the saliva analysis has a very prospective chance to substitute or alternate the biochemical analysis of blood plasma due to the mentioned advantage and to attribute more information on the processes in the human body. (Fig. 1, Ref. 16.)

[Fe2+-induced oxidative processes in the liver mitochondria of rats]. / Oxidacné procesy mitochondrií pecene potkana indukované Fe2+.

The study investigated the prooxidative in vitro effect of various Fe(2+)-EDTA concentrations on biochemical parameters of the energetic metabolism of rat liver mitochondria. Fe(2+)-EDTA was added in concentrations 150, 300 and 400 mmol/mg of mitochondrial protein. The study included the investigation of consumption of oxygen in state 4 (without ADP addition) and in state 3 (with ADP addition), and the activities of ATP-ase, superoxide dismutase (SOD) and glutathione reductase. The mitochondrial outer membrane dynamics were simultaneously monitored by the method of synchronous fluorescence fingerprint. When compared with the control group, the results imply that in state 4, the addition of 150 mmol of Fe2+/mg of mitochondrial protein caused an insignificant increase in respiration to 104%, whereas in state 3, the oxygen consumption was insignificantly inhibited to 82%. The activity of ATPase was insignificantly raised to 105%, whereas the superoxide dismutase activity has decreased significantly to 77%. The activity of glutathione reductase increased significantly to 124%. The addition of 300 mmol of Fe2+/mg of mitochondrial protein has caused a significant inhibition of oxygen consumption to 67% in state 4 and to 31% in state 3. The activity of ATPase showed an insignificant elevation to 104%. The activity of superoxide dismutase was significantly reduced to 52% and that of glutathione reductase dropped to 72%. The addition of 400 Fe2+/mg of mitochondrial protein strongly diminished the oxygen consumption to 36% in state 4, and similarly to 37% in state 3. The activity of ATP-ase was significantly decreased to 39%, the superoxide dismutase activity diminished to 17% and glutathione reductase activity dropped to 37%. The monitoring of the mitochondrial outer membrane by the analysis of synchronous fluorescence fingerprint showed that the membrane is involved in these processes. (Fig. 5, Ref. 12.)

In vitro effect of stobadine on Fe(2+)-induced oxidative stress in rat liver mitochondria.

The authors have studied the susceptibility of two key protective enzymes, glutathione peroxidase (GPX) and glutathione reductase (GR) to the reactive oxygen species (ROS) known to induce oxidative damage in vitro system containing Fe2+/EDTA. The ability of ROS scavanger stobadine to prevent oxidative damage was also studied. Incubation of GPX with Fe2+/EDTA resulted in the significant decrease in its enzyme activity while under the same condition the activity of GR was not changed. The presence of stobadine was effective in protecting GPX from the loss of its activity by in vitro oxidizing agents. The monitoring of the mitochondrial outer membrane dynamics by the method of synchronous fluorescence fingerprint showed that the membrane is involved in these processes. (Fig. 3, Ref. 35.)