The Effect of Cross-Sex Fecal Microbiota Transplantation on Metabolism and Hormonal Status in Adult Rats.

Increasing evidence of sexual dimorphism in the pathophysiology of metabolic complications caused by sex steroids is under investigation. The gut microbiota represents a complex microbial ecosystem involved in energy metabolism, immune response, nutrition acquisition, and the health of host organisms. Gender-specific differences in composition are present between females and males. The purpose of this study was to use cross-sex fecal microbiota transplantation (FMT) for the detection of sex-dependent metabolic, hormonal, and gut microbiota changes in female and male recipients. Healthy non-obese female and male Wistar rats were divided into donor, same-sex, and cross-sex recipient groups. After a 30-day period of FMT administration, biochemical markers (glucose and lipid metabolism) and sex hormones were measured, and the gut microbiota was analyzed. The cross-sex male recipients displayed a significantly lower testosterone concentration compared to the males that received same-sex FMT. Sex-dependent changes caused by cross-sex FMT were detected, while several bacterial taxa correlated with plasma testosterone levels. This study represents the first to study the effect of cross-sex changes in the gut microbiome concerning metabolic and hormonal changes/status in adult non-obese Wistar rats. Herein, we present cross-sex FMT as a potential tool to modify sex-specific pathologies.

Endogenous DNase Activity in an Animal Model of Acute Liver Failure.

Deoxyribonucleases (DNases) cleave extracellular DNA (ecDNA) and are under intense research as interventions for diseases associated with high ecDNA, such as acute live injury. DNase I treatment decreases morbidity and mortality in this animal model. Endogenous DNase activity has high interindividual variability. In this study, we tested the hypothesis that high endogenous DNase activity is beneficial in an animal model of acute liver failure. DNase activity was measured in the plasma of adult male mice taken before i.p. injection of thioacetamide to induce acute liver failure. The survival of mice was monitored for 48 h. Mice were retrospectively divided into two groups based on the median DNase activity assessed using the gel-based single-radial enzyme diffusion assay. In acute liver failure, mice with a higher baseline DNase activity had lower mortality after 48 h (by 25%). Different protection of ecDNA against nucleases by vesicles or DNA-binding proteins could play a role and should be further evaluated. Similarly, the role of endogenous DNase activity should be analyzed in other disease models associated with high ecDNA.

Gut Dysbiosis and Fecal Microbiota Transplantation in Autoimmune Diseases.

Gut microbiota dysbiosis has recently been reported in a number of clinical states, including neurological, psychiatric, cardiovascular, metabolic and autoimmune disorders. Yet, it is not completely understood how colonizing microorganisms are implicated in their pathophysiology and molecular pathways. There are a number of suggested mechanisms of how gut microbiota dysbiosis triggers or sustains extraintestinal diseases; however, none of these have been widely accepted as part of the disease pathogenesis. Recent studies have proposed that gut microbiota and its metabolites could play a pivotal role in the modulation of immune system responses and the development of autoimmunity in diseases such as rheumatoid arthritis, multiple sclerosis or type 1 diabetes. Fecal microbiota transplantation (FMT) is a valuable tool for uncovering the role of gut microbiota in the pathological processes. This review aims to summarize the current knowledge about gut microbiota dysbiosis and the potential of FMT in studying the pathogeneses and therapies of autoimmune diseases. Herein, we discuss the extraintestinal autoimmune pathologies with at least one published or ongoing FMT study in human or animal models.

Circulating extracellular DNA is in association with continuous metabolic syndrome score in healthy adolescents.

Obesity is associated with chronic low-grade inflammation that eventually leads to metabolic complications. Extracellular DNA (ecDNA) is a damage-associated molecular pattern. Extracellular mitochondrial DNA can activate innate immunity. We hypothesized that ecDNA, especially of mitochondrial origin, could be associated with components of the metabolic syndrome in young healthy probands. In a cross-sectional study, healthy adolescents (n = 1,249) provided blood samples. Anthropometric data, blood pressure, and blood counts were assessed. In addition, biochemical analysis of sera or plasma was conducted, including the quantification of advanced oxidation protein products (AOPPs) as a marker of oxidative stress induced by neutrophil or monocyte activation. Plasma ecDNA was isolated and measured by fluorometry. Nuclear and mitochondrial DNA were quantified by real-time PCR. Males had higher total plasma ecDNA [15 (11-21) vs. 11 (8-17) ng/mL; median (interquartile range)], nuclear [1,760 (956-3,273) vs. 1,153 (600-2,292) genome equivalents (GE)/mL], and mitochondrial [37,181 (14,836-90,896) vs. 30,089 (12,587-72,286) GE/mL] DNA. ecDNA correlated positively with the continuous metabolic syndrome score (r = 0.158 for males and r = 0.134 for females). Stronger correlations were found between ecDNA of mitochondrial origin and AOPP (r = 0.202 and 0.186 for males and females, respectively). Multivariate regression analysis revealed associations of nuclear DNA with leukocyte and erythrocyte counts. The results of this study of healthy adolescents show that circulating ecDNA is associated with the risk of metabolic syndrome, not with obesity per se. The association between mitochondrial ecDNA and AOPP requires further attention as it supports a potential role of mitochondria-induced sterile inflammation in the pathogenesis of the metabolic syndrome.

Viruses in Cancers of the Digestive System: Active Contributors or Idle Bystanders?

The human virome, which is a collection of all the viruses that are present in the human body, is increasingly being recognized as an essential part of the human microbiota. The human gastrointestinal tract and related organs (e.g., liver, pancreas, and gallbladder)-composing the gastrointestinal (or digestive) system-contain a huge number of viral particles which contribute to maintaining tissue homeostasis and keeping our body healthy. However, perturbations of the virome steady-state may, both directly and indirectly, ignite/sustain oncogenic mechanisms contributing to the initiation of a dysplastic process and/or cancer progression. In this review, we summarize and discuss the available evidence on the association and role of viruses in the development of cancers of the digestive system.

Cell-Free Nucleic Acids and their Emerging Role in the Pathogenesis and Clinical Management of Inflammatory Bowel Disease.

Cell-free nucleic acids (cfNAs) are defined as any nucleic acids that are present outside the cell. They represent valuable biomarkers in various diagnostic protocols such as prenatal diagnostics, the detection of cancer, and cardiovascular or autoimmune diseases. However, in the current literature, little is known about their implication in inflammatory bowel disease (IBD). IBD is a group of multifactorial, autoimmune, and debilitating diseases with increasing incidence worldwide. Despite extensive research, their etiology and exact pathogenesis is still unclear. Since cfNAs were observed in other autoimmune diseases and appear to be relevant in inflammatory processes, their role in the pathogenesis of IBD has also been suggested. This review provides a summary of knowledge from the available literature about cfDNA and cfRNA and the structures involving them such as exosomes and neutrophil extracellular traps and their association with IBD. Current studies showed the promise of cfNAs in the management of IBD not only as biomarkers distinguishing patients from healthy people and differentiating active from inactive disease state, but also as a potential therapeutic target. However, the detailed biological characteristics of cfNAs need to be fully elucidated in future experimental and clinical studies.

Antioxidant vitamins prevent oxidative and carbonyl stress in an animal model of obstructive sleep apnea.

PURPOSE: The aim of our study was to analyze the effects of an antioxidant treatment on markers of oxidative and carbonyl stress in a rat model of obstructive sleep apnea. METHODS: Wistar rats were randomized into six groups-according to gender and intervention-sham, intermittent hypoxia, and intermittent hypoxia with treatment by vitamins C and E. Rats underwent tracheostomy. The tracheal cannula was closed for 12 s every minute for 1 h to simulate obstructive sleep apnea-related intermittent hypoxia. In the treatment group, rats received vitamin C and E 24 h prior to surgery. RESULTS: The intervention had a significant effect on advanced oxidation protein products (p = 0.008) and advanced glycation end products-specific fluorescence (p = 0.006) but no effect on malondialdehyde. Oxidation and glycation protein products were higher in intermittent hypoxia groups than in sham and in treated groups. CONCLUSIONS: Antioxidants alleviate oxidative and carbonyl stress in an experimental model of obstructive sleep apnea. Future studies will show whether such treatment has any clinical value regarding cardiovascular complications of sleep apnea syndrome, preferably in patients with low compliance to continuous positive airway pressure.

The short-term effects of soybean intake on oxidative and carbonyl stress in men and women.

Beyond other beneficial effects, a soy-rich diet has been shown to reduce the risk of cardiovascular diseases and diabetic complications. Reduction of oxidative and carbonyl stress has been proposed as the underlying mechanism, but the evidence for this is lacking. The aim of our study was to evaluate the effects of short-term increased soy intake on oxidative and carbonyl stress parameters in young volunteers. Young healthy probands (omnivores) of both genders (55 women, 33 men) were given soybeans (2 g/kg bodyweight daily) for one week. Markers of oxidative and carbonyl stress were measured in plasma at the beginning and at the end of one week soybean intake and after another week of a wash-out period. Total antioxidant capacity was increased by soybean intake in both genders. This led to decreased levels of advanced oxidation protein products in women, but not in men. On the contrary, in men, soybean intake increased lipoperoxidation. No effects on carbonyl stress markers (advanced glycation end products-specific fluorescence and fructosamine) were found. Soybean intake has gender-specific effects on oxidative stress in young healthy probands potentially due to divergent action and metabolism of phytoestrogens in men and women. Effects of soybean intake on carbonyl stress should be evaluated in longer studies.

Oxidative and carbonyl stress in patients with obstructive sleep apnea treated with continuous positive airway pressure.

PURPOSE: The pathogenesis of cardiovascular complications of obstructive sleep apnea syndrome (OSAS) can be explained by oxidative and carbonyl stress due to oxygenation and reoxygenation injury during sleep. This hypothesis has yet to be proved experimentally, although several clinical observations have found increased oxidative damage in plasma. Continuous positive airway pressure (CPAP) improves symptoms and prognosis of patients with OSAS. METHODS: Patients with confirmed SAS (n = 89) underwent polysomnography and received CPAP treatment. Plasma and saliva samples were taken before CPAP therapy as well as after 1 and 6 months of CPAP treatment. Selected markers of oxidative and carbonyl stress were measured in plasma and saliva, and their dynamics was statistically analyzed. RESULTS: Plasma levels of thiobarbituric acid reacting substances-a marker of lipoperoxidation-and advanced glycation end products (AGEs)-a marker of carbonyl stress-were decreased by the CPAP therapy. The decrease of AGEs and fructosamine was also found in saliva. Interestingly, no gender differences and no changes of antioxidant status measured as total antioxidant capacity and ferrous reducing ability were found in either of the samples. CONCLUSION: Previous findings of lowered plasma markers of oxidative stress were confirmed. Plasma AGEs were lowered by CPAP therapy. This is the first study analyzing markers of oxidative and carbonyl stress in saliva. Non-invasive sampling of saliva makes it a very interesting source of information for repeated monitoring of therapy success. Salivary AGEs and fructosamine as markers of carbonyl stress were decreased by the CPAP therapy and might therefore have potential informative value for clinical observations, as well as for the understanding of the pathogenesis of OSAS complications.

Lyme borreliosis--epidemiological analysis of incidence in the northern region of Slovakia.

Lyme borreliosis is a contemporary public health problem. That's why we devoted our prospective and retrospective epidemiological study to the incidence of anthropozoonosis in the regions of Liptovský Mikulás and Ruzomberok. We created a group of 476 patients from the medical documentation of infectious units. These patients were treated for Lyme borreliosis from 1989 to 2010, 280 patients in the county of Liptovský Mikulás, and 196 patients in the county of Ruzomberok. Morbidity in different years was compared to national data. The number of ill patients (n = 476) compared to data about reported cases from The Regional Public Health Office in Liptovský Mikulás (n = 221) confirmed the lack of a warning service. The actual incidence of Lyme disease in the Liptov region is twice higher. The average morbidity was 16.24 people per 100,000 of the population for the last 22 years. The highest morbidity from 476 treated patients (men 37.52%, women 62.48%) was in the group aged from 45 to 54 years with an average annual morbidity 21.18/100,000. The study also confirmed the higher incidence of Lyme disease in the female population.

The Citrullination-Neutrophil Extracellular Trap Axis in Chronic Diseases.

Citrullination of proteins is crucial for the formation of neutrophil extracellular traps (NETs) - strands of nuclear DNA expulsed in the extracellular environment along with antimicrobial proteins in order to halt the spread of pathogens. Paradoxically, NETs may be immunogenic and contribute to inflammation. It is known that for the externalization of DNA, a group of enzymes called peptidyl arginine deiminases (PADs) is required. Current research often looks at citrullination, NET formation, PAD overexpression, and extracellular DNA (ecDNA) accumulation in chronic diseases as separate events. In contrast, we propose that citrullination can be viewed as the primary mechanism of autoimmunity, for instance by the formation of anti-citrullinated protein antibodies (ACPAs) but also as a process contributing to chronic inflammation. Therefore, citrullination could be at the center, connecting and impacting multiple inflammatory diseases in which ACPAs, NETs, or ecDNA have already been documented. In this review, we aimed to highlight the importance of citrullination in the etiopathogenesis of a number of chronic diseases and to explore the diagnostic, prognostic, and therapeutic potential of the citrullination-NET axis.

The Human Mycobiome: Colonization, Composition and the Role in Health and Disease.

The mycobiome is the fungal component of the human microbial ecosystem that represents only a small part of this environment but plays an essential role in maintaining homeostasis. Colonization by fungi begins immediately after birth. The initial mycobiome is influenced by the gestational age of a newborn, birth weight, delivery method and feeding method. During a human's life, the composition of the mycobiome is further influenced by a large number of endogenous and exogenous factors. The most important factors are diet, body weight, age, sex and antibiotic and antifungal therapy. The human mycobiome inhabits the oral cavity, gastrointestinal tract, respiratory tract, urogenital tract and skin. Its composition can influence the gut-brain axis through immune and non-immune mediated crosstalk systems. It also interacts with other commensals of the ecosystem through synergistic and antagonistic relationships. Moreover, colonization of the gut by opportunistic fungal pathogens in immunocompromised individuals can lead to clinically relevant disease states. Thus, the mycobiome represents an essential part of the microbiome associated with a variety of physiological and pathological processes. This review summarizes the current knowledge on the composition of the mycobiome in specific sites of the human body and its role in health and disease.

Fecal Microbiota Transplantation as a Tool for Therapeutic Modulation of Non-gastrointestinal Disorders.

Fecal microbiota transplantation has been primarily investigated as a therapeutic tool for a number of gut disorders. Optimistic results from clinical studies on Clostridium difficile infection, inflammatory bowel disease and irritable bowel syndrome have stimulated the expansion of possible indications in which FMT might represent a game changing approach. Microbial dysbiosis was shown in a number of non-gastrointestinal disorders. Moreover, FMT was proven to be effective in therapy of numerous animal models of disease. However, only a proportion of these disorders have been addressed in clinical studies using FMT. These include obesity, non-alcoholic fatty liver disease, cardiovascular inflammation and neurological disorders such as autism, depression and Parkinson's disease. Results from preclinical and clinical studies also outlined possible molecular mechanisms that contribute to alleviation of the disease. These range from increasing the circulating levels of microbial metabolites (trimethylamine N-oxide, lipopolysaccharide, short chain fatty acids) to stimulation of the enteric nervous system. Several methodological shortcomings are still to be addressed; however, positive results of the clinical studies indicate that further investigation of FMT as a therapeutic tool for non-gastrointestinal disorders can be expected in upcoming years.

Metalloproteinases in Inflammatory Bowel Diseases.

Inflammatory bowel diseases (IBD) are chronic inflammatory diseases of the gastrointestinal tract, encompassing two main disorders: Crohn's disease (CD) and ulcerative colitis (UC). In both these pathologies, excessive and local immune response against luminal antigens promotes a pathological process leading to various degrees of gut damage. Matrix metalloproteinases (MMPs) are a family of neutral proteases with the ability to degrade all components of extracellular matrix. In physiological conditions, MMPs are produced at very low level and generally in the latent form and are involved in the normal tissue turnover. Their function is inhibited by tissue inhibitors of metalloproteinases (TIMPs). However, in inflamed tissue of IBD patients, MMPs are produced in excess and/or the activity of TIMPs is not sufficient to block MMPs, thereby making a major contribution to the IBD-related mucosal degradation. In this review, we summarize the available evidence on the expression and role of MMPs in IBD.

Extracellular DNA Correlates with Intestinal Inflammation in Chemically Induced Colitis in Mice.

Circulating extracellular DNA (ecDNA) is known to worsen the outcome of many diseases. ecDNA released from neutrophils during infection or inflammation is present in the form of neutrophil extracellular traps (NETs). It has been shown that higher ecDNA concentration occurs in a number of inflammatory diseases including inflammatory bowel disease (IBD). Enzymes such as peptidyl arginine deiminases (PADs) are crucial for NET formation. We sought to describe the dynamics of ecDNA concentrations and fragmentation, along with NETosis during a mouse model of chemically induced colitis. Plasma ecDNA concentration was highest on day seven of dextran sulfate sodium (DSS) intake and the increase was time-dependent. This increase correlated with the percentage of cells undergoing NETosis and other markers of disease activity. Relative proportion of nuclear ecDNA increased towards more severe colitis; however, absolute amount decreased. In colon explant medium, the highest concentration of ecDNA was on day three of DSS consumption. Early administration of PAD4 inhibitors did not alleviate disease activity, but lowered the ecDNA concentration. These results uncover the biological characteristics of ecDNA in IBD and support the role of ecDNA in intestinal inflammation. The therapeutic intervention aimed at NETs and/or nuclear ecDNA has yet to be fully investigated.

Melatonin interactions with blood pressure and vascular function during L-NAME-induced hypertension.

The mechanisms responsible for the antihypertensive effect of melatonin are not completely understood. To elucidate the possible role of the nitric oxide (NO) pathway in the hemodynamic actions of melatonin, the effects of this indolamine on vascular function during hypertension induced by the NO-synthase (NOS) inhibitor, N(omega)-nitro-L-arginine-methyl ester (L-NAME) were investigated. Four groups of male adult Wistar rats were employed: control, L-NAME (40 mg/kg), melatonin (10 mg/kg) and L-NAME + melatonin for 5 wks. Systolic and diastolic blood pressure were measured invasively in the carotid artery. Conjugated dienes concentration (an oxidative load marker), NOS RNA expression and its activity and RNA expression of cyclooxygenase-(COX)-1 and COX-2 were determined in the aorta. Acetylcholine-induced responses and their NO-mediated component were evaluated in femoral and mesenteric artery. Moreover, endothelium-derived constricting factor (EDCF)-dependent vasoconstriction and inner diameter were determined in the femoral artery. Chronic L-NAME treatment induced hypertension, elevated the oxidative load and inhibited NOS activity. Moreover, impaired NO-dependent relaxation, augmented EDCF-constriction, increased COX-2 expression and reduced arterial inner diameter were observed. Melatonin added to L-NAME treatment completely prevented elevation of the oxidative load in the aorta. However, melatonin was not able to prevent NOS activity decline, elevation of COX-2 expression or the impairment of vascular responses (except moderate improvement in relaxation of small mesenteric arteries) and it exerted only slight antihypertensive effect. In conclusion, in addition to the reduction of the oxidative load, the restoration of the NO pathway seems to play an important role in the antihypertensive effect of melatonin.

Oral in vivo bactofection in dextran sulfate sodium treated female Wistar rats.

Salmonella typhimurium SL7207 carrying Cu-Zn superoxide dismutase and an N-terminal deletion mutant of monocyte chemoattractant protein-1 genes was applied to dextran sodium sulfate treated female Wistar rats. Stool quality, food and water intake were monitored. Markers of oxidative stress, interleukin 1, interleukin 6 and tumor necrosis factor alpha were quantified. No differences were found in body weights, markers of oxidative stress in plasma and inflammatory markers in colon homogenates. Plasma concentrations of I11, I16 were lower in the treatment groups than in the dextran sodium sulfate group. However, dextran sodium sulfate induced inflammation could not be confirmed by plasma levels of I11, I16 and TNFalpha. Although some parameters showed a tendency to improve, the inflammation caused by administration of 4% dextran sodium sulfate during 7 days was low and contradictory to other studies. Results showed the potential synergic effect of combined bacteria-mediated antioxidative and anti-inflammatory gene therapy.

Phages and Their Role in Gastrointestinal Disease: Focus on Inflammatory Bowel Disease.

Inflammatory bowel diseases (IBDs) are a group of chronic autoinflammatory diseases including Crohn's disease and ulcerative colitis. Although the molecular mechanisms governing the pathogenesis of gastrointestinal inflammation are not completely clear, the main factors are presumed to be genetic predisposition, environmental exposure, and the intestinal microbiome. Hitherto, most of the studies focusing on the role of the microbiome studied the action and effect of bacteria. However, the intestinal microbiome comprises other members of the microbial community as well, namely, fungi, protozoa, and viruses. We believe that bacteriophages are among the main orchestrators of the effect of microbiota on the gut mucosa. Therefore, this review aims to summarize the knowledge of the role of intestinal phageome in IBD and to discuss the concept of phage therapy and its future applications.

Salivary microbiome composition changes after bariatric surgery.

Recent studies show that the salivary microbiome in subjects with obesity differ from those without obesity, but the mechanism of interaction between the salivary microbiome composition and body weight is unclear. Herein we investigate this relation by analyzing saliva samples from 35 adult patients with obesity undergoing bariatric surgery. Our aim was to describe salivary microbiome changes during body weight loss on an individual-specific level, and to elucidate the effect of bariatric surgery on the salivary microbiome which has not been studied before. Analysis of samples collected before and 1 day after surgery, as well as 3 and 12 months after surgery, showed that the salivary microbiome changed in all study participants, but these changes were heterogeneous. In the majority of participants proportions of Gemella species, Granulicatella elegans, Porphyromonas pasteri, Prevotella nanceiensis and Streptococcus oralis decreased, while Veillonella species, Megasphaera micronuciformis and Prevotella saliva increased. Nevertheless, we found participants deviating from this general trend which suggests that a variety of individual-specific factors influence the salivary microbiome composition more effectively than the body weight dynamics alone. The observed microbiome alternations could be related to dietary changes. Therefore, further studies should focus on association with altered taste preferences and potential oral health consequences.

Nuclear and Mitochondrial Circulating Cell-Free DNA Is Increased in Patients With Inflammatory Bowel Disease in Clinical Remission.

Background: The role of cell-free DNA (cfDNA) in the pathogenesis of inflammatory bowel disease (IBD) has been recently suggested. The aim of this study was to analyze circulating cfDNA and deoxyribonuclease (DNase) activity in IBD patients in clinical remission. Materials and Methods: Plasma and serum were obtained from 72 patients with Crohn's disease and 28 patients with ulcerative colitis. Total cfDNA, nuclear DNA (ncDNA), mitochondrial DNA (mtDNA) and DNase activity were measured. Results: IBD patients showed higher levels of both ncDNA and mtDNA compared to healthy controls. Concentration of ncDNA was higher in males compared to females, including patients and healthy controls. However, unlike males higher amount of ncDNA was found in female IBD patients compared to healthy controls. DNase activity was significantly lower in male IBD patients compared with healthy controls. In addition, there was a negative correlation between DNase activity and ncDNA levels in male IBD patients. Conclusions: Herein we present increased amount of circulating ncDNA and mtDNA in IBD patients in clinical remission. Thus, unlike total cfDNA, circulating ncDNA and mtDNA might not represent the optimal biomarkers of disease activity. This is also the first report on sex difference in circulating ncDNA levels, possibly associated with lower DNase activity in males.