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Background: Disturbances in the gut microbiota may act as mechanisms influencing the interplay between dietary factors and metabolic disorders. Studies have demonstrated that these alterations are associated with the diagnosis of polycystic ovary syndrome (PCOS). Within this context, we aimed to investigate associations between gut microbiota, gut-derived metabolites (short-chain fatty acids [SCFAs] and indole-3-propionic acid [IPA]), and dietary intake in women with PCOS., Methods: We conducted a cross-sectional study of 24 women with PCOS, previously recruited for two studies at our research center, compared with 14 age-matched healthy controls. The mean (SD) age of all 38 participants was 33.3 (7.5) years, and the mean (SD) body mass index was 29.5 (4.8) kg/m 2 . Primary outcomes included gut microbiota analysis by sequencing the V4 region of the 16 S rRNA gene, serum IPA levels measured by liquid chromatography/triple-quadrupole mass spectrometry (LC-QqQ-MS), and fecal and plasma SCFA levels measured by LC-MS/MS., Results: Gut microbiota diversity, composition, and metabolic pathways differed between the PCOS and control groups. A higher abundance of two operational taxonomic units specializing in complex carbohydrate metabolism was observed in healthy control women. The PCOS group exhibited a less favorable dietary intake than the control group, and a significant correlation was observed between gut microbiota composition and dietary glycemic load in PCOS (r = 0.314, P = 0.03 in Mantel test). Multivariable-adjusted linear regression models indicated that lower levels of IPA and higher circulating levels of two SCFAs (acetic acid and propionic acid) were independently associated with the diagnosis of PCOS., Conclusions: Our data support the differentiation between women with PCOS and healthy controls based on gut microbiota analysis. Furthermore, changes in gut bacteria and their metabolites could be, at least in part, the biological mechanism by which a low glycemic load diet may potentially improve PCOS-related reproductive and cardiometabolic outcomes., Competing Interests: Declarations. Consent for publication: Consent forms are available from the corresponding author on request. Competing interests: The authors declare no competing interests. Human Ethics and Consent to Participate: Each study participant provided written informed consent before enrollment. The study was approved by the HCPA Ethics Committee (CAAE 35025414.1.0000.5327) and conducted in accordance with the Helsinki Declaration. Clinical trial number: Not applicable., (© 2024. The Author(s).)

The gut microbiota plays a crucial role in modulating the immune response during COVID-19, with several studies reporting significant alterations in specific bacterial genera, including Akkermansia , Bacteroides , Bifidobacterium , Faecalibacterium , Lactobacillus , Oscillospira , and Ruminococcus . These genera are symbionts of the gut microbiota and contribute to host health. However, comparing results across studies is challenging due to differences in analysis methods and reference databases. We screened 16S rRNA raw datasets available in public databases on COVID-19, focusing on the V3-V4 region of the bacterial genome. In total, seven studies were included. All samples underwent the same bioinformatics pipeline, evaluating the differential abundance of these seven bacterial genera at each level of severity. The reanalysis identified significant changes in differential abundance. Bifidobacterium emerged as a potential biomarker of disease severity and a therapeutic target. Bacteroides presented a complex pattern, possibly related to disease-associated inflammation or opportunistic pathogen growth. Lactobacillus showed significant changes in abundance across the COVID-19 stages. On the other hand, Akkermansia and Faecalibacterium did not show significant differences, while Oscillospira and Ruminococcus produced statistically significant results but with limited relevance to COVID-19 severity. Our findings reveal new insights into the differential abundance of key bacterial genera in COVID-19, particularly Bifidobacterium and Bacteroides .

The COVID-19 pandemic has led to the emergence of acute and chronic post-COVID syndromes, which present diverse clinical manifestations. The underlying pathophysiology of these conditions is not yet fully understood, but genetic instability has been proposed as a potential contributing factor. This study aimed to explore the differential impact of physical and psychological health factors on genetic instability in individuals with acute and chronic post-COVID syndromes. In this study, three groups of subjects were analyzed: a control group, an acute post-COVID group, and a chronic post-COVID group, with a total of 231 participants. The participants were assessed using a questionnaire for long-COVID-19COVID, and female participants reported more symptoms than male participants in areas related to fatigue, memory, mental health, and well-being during the chronic phase. Genetic instability was assessed using the comet assay, and participants' physical and psychological profiles were evaluated. The overall results showed no significant differences in DNA damage, as measured by the comet assay, among the three groups, suggesting that genetic instability, as assessed by this method, may not be a primary driver of the distinct clinical presentations observed in post-COVID syndromes. However, when gender was considered, male participants in the acute long COVID group exhibited higher levels of genetic instability compared to females. Multiple linear regression analysis revealed that gender, age, and waist circumference were significant predictors of DNA damage. Among females in the acute group, sexual health, and eye-related symptoms significantly influenced the increase in DNA damage. These findings indicate the need for further investigation on the gender-specific differences in genetic instability and their potential implications for the pathophysiology of post-COVID syndromes. Exploring alternative markers of genetic instability and the interplay between genetic, inflammatory, and cellular processes could provide valuable insights for the management of these debilitating post-viral sequelae., (© The Author(s) 2024. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

This study aimed to characterize the taxonomic composition of intraradicular multispecies biofilms (IMBs) formed in situ in a model to reproduce clinical conditions. Twelve palatal roots of maxillary molars had its canals prepared. Two roots were randomly selected to sterility control. Ten intraoral prosthetic appliances with lateral slots were fabricated. The roots were positioned in the slots with the canal access open to the oral cavity. Eight volunteers wore the appliance for 21 days, and two wore it at two different time points. One root from each appliance was removed and stored at -20°C until DNA extraction and sequencing (n = 10). Biofilm was analyzed using next-generation sequencing and bioinformatics. The V4 hyper-variable region of the 16SrRNA gene was amplified and sequenced. For data analyses, the mothur pipeline was used for 16SrRNA processing, and subsequent analyses of the sequence dataset were performed in R using the MicrobiomeAnalyst R package. The taxonomy-based analysis of bacterial communities identified 562 operational taxonomic units (OTUs), which belonged to 93 genera, 44 families, and 8 phyla. Bacterial colonization was different for each biofilm, and samples did not have the same group of bacteria. Alpha and beta diversity analysis revealed some general patterns of sample clustering. A core microbiome of prevalent OTUs and genera was identified. IMBs were heterogeneous when analyzed individually, but some diversity patterns were found after sample clustering. The experimental model seemed to reproduce the actual biofilm composition in endodontic infections, which suggests that it may be used to evaluate disinfection protocols., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This study aimed to characterize the taxonomic composition of intraradicular multispecies biofilms (IMB) formed in situ in a model to reproduce clinical conditions. Twelve palatal roots of maxillary molars had its canals prepared. Two roots were randomly selected to sterility control. Ten intraoral prosthetic appliances with lateral slots were fabricated. The roots were positioned in the slots with the canal access open to the oral cavity. Eight volunteers wore the appliance for 21 days, and two wore it at two different time points. One root from each appliance was removed and stored at -20°C until DNA extraction and sequencing (n = 10). Biofilm was analyzed using next-generation sequencing and bioinformatics. The V4 hyper-variable region of the 16SrRNA gene was amplified and sequenced. For data analyses, the mothur pipeline was used for 16SrRNA processing, and subsequent analyses of the sequence dataset were performed in R using the Microbiome Analyst R package. The taxonomy-based analysis of bacterial communities identified 562 operational taxonomic units (OTUs), which belonged to 93 genera, 44 families, and 8 phyla. Bacterial colonization was different for each biofilm, and samples did not have the same group of bacteria. Alpha and beta diversity analysis revealed some general patterns of sample clustering. A core microbiome of prevalent OTUs and genera was identified. IMBs were heterogeneous when analyzed individually, but some diversity patterns were found after sample clustering. The experimental model seemed to reproduce the actual biofilm composition in endodontic infections, which suggests that it may be used to evaluate disinfection protocols., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This study aimed to investigate the morphological characteristics and phylogenetic relationships of three new species of Tropicoporus from the southern parts of India. The analyses of the ITS and nLSU regions revealed the novelty of these species, which have been named T. pannaensis , T. subindicus , and T. xerophyticus . All three species possess pileate basidiomes, a monomitic hyphal system in the context, and the presence of cystidioles and setae. However, they differ significantly in their phylogenetic placements and other morpho-taxonomic features. Tropicoporus pannaensis is characterized by a meagrely ungulate basidiome, indistinct zones, and an obtuse margin. Tropicoporus subindicus has a triquetrous basidiome and a radially cracked, crusted pileal surface with an acute margin, while T. xerophyticus is distinguished by an imbricate, perennial basidiome with an abundantly warted pileal surface. A phylogenetic tree is provided to show the placement of the three new species, along with detailed descriptions and illustrations. Additionally, a key for the identification of the Asian species of Tropicoporus is presented.

Background: Some evidence suggests an association between gut dysbiosis and cirrhosis progression. The authors investigated Gut Microbiome (GM) influence on 90-day mortality and hospitalization/rehospitalization rates in cirrhotic patients., Methods: Compensated/decompensated outpatients and decompensated inpatients were prospectively included and compared to healthy controls. Clinical, laboratory, GM, and two ratios between phyla were evaluated. Patients were followed up for 90 days for hospitalization/rehospitalization and mortality., Results: 165 individuals were included (50 compensated, 49 decompensated outpatients; 36 decompensated inpatients; 30 healthy), 48.5 % female, mean age was 61, main cirrhosis etiology was hepatitis C (27.3 %), and mostly Child-Pugh (CP) B patients, median MELD of 13. As liver disease progressed, microbiota diversity decreased between the groups (p = 0.05; p < 0.004). There were 9 deaths and 22 hospitalizations or rehospitalizations. GM composition had correlation with norfloxacin (p = 0.36, p = 0.04), encephalopathy (p = 0.31, p = 0.01), lactulose (p = 0.26, p = 0.01), 90-day mortality (p = 0.22, p = 0.04), CP (p = 0.17, p = 0.01), previous 6-month antibiotic use (p = 0.16, p = 0.01), MELD (p = 0.145, p = 0.01), ALBI (p = 0.1, p = 0.04) and 90-day hospitalization/rehospitalization (p = 0.08, p = 0.03). Firmicutes/Bacteroidetes (F/B) and Firmicutes/Proteobacteria (F/P) ratios were progressively lower and more significant and had an association with 90-day mortality (p < 0.001). Three MELD set-points (≥ 15, 18 and 20) were significantly associated with both ratios, with similar accuracies., Conclusions: GM dysbiosis was associated with higher CP, MELD, 90-day mortality and hospitalization/rehospitalization. F/B and F/P ratios were associated with 90-day mortality., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024. Published by Elsevier España, S.L.U.)

Major depressive disorder (MDD) is a global health concern, affecting over 250 million individuals worldwide. In recent years, the gut-brain axis has emerged as a promising field for understanding the pathophysiology of MDD. Microbial metabolites, such as short-chain fatty acids (SCFAs)-acetate, butyrate, and propionate-, have gained attention for their potential to influence epigenetic modifications within the host brain. However, the precise mechanisms through which these metabolites participate in MDD pathophysiology remain elusive. This study was designed to investigate the effects of oral SCFA supplementation in adult male Wistar rats subjected to chronic unpredictable mild stress (CUMS). A subset of control and CUMS-exposed rats received different supplementations: sodium acetate (NaOAc) at a concentration of 60 mM, sodium butyrate (NaB) at 40 mM, sodium propionate (NaP) at 50 mM, or a mixture of these SCFAs. The gut microbiome was assessed through 16S rRNA sequencing, and epigenetic profiling was performed using Western blot analysis. Results demonstrated that NaP supplementation significantly alleviated anhedonia in stressed animals, as evidenced by improved performance in the sucrose consumption test. This ameliorative effect was potentially associated with the modulation of gut bacterial communities, accompanied by the attenuation of the region-specific epigenetic dysregulation in the brain of the animals exposed to chronic stress. These findings suggest a potential association between gut dysbiosis and stress response, and NaP could be a promising target for future MDD interventions. However, further studies are needed to fully elucidate the underlying mechanisms of these effects., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Metabolic-dysfunction associated steatotic liver disease (MASLD) is a hepatic manifestation of metabolic syndrome. Studies suggest ornithine aspartate (LOLA) as drug therapy., Aim: To analyze the influence of LOLA intake on gut microbiota using a nutritional model of MASLD., Methods: Adult male Sprague Dawley rats were randomized into three groups: Control (10 rats fed with a standard diet), MASLD (10 rats fed with a high-fat and choline-deficient diet), and LOLA (10 rats receiving 200 mg/kg/d LOLA, after the 16 th week receiving high-fat and choline-deficient diet). After 28 wk of the experiment, animals were euthanized, and feces present in the intestine were collected. Following fecal DNA extraction, the V4 region of the 16S rRNA gene was amplified followed by sequencing in an Ion S5™ system., Results: Alpha and beta diversity metrics were comparable between MASLD and LOLA. 3 OTUs were differentially abundant between MASLD and LOLA, which belong to the species Helicobacter rodentium , Parabacteroides goldsteinii , and Parabacteroides distasonis . The functional prediction provided two different metabolic profiles between MASLD and LOLA. The 9 pathways differentially abundant in MASLD are related to a change in energy source, adenosine/purine nucleotides degradation as well as guanosine and adenosine deoxyribonucleotides biosynthesis. The 14 pathways differentially abundant in LOLA are associated with four major metabolic functions primarily influenced by L-aspartate, including tricarboxylic acid cycle pathways, purine/guanosine nucleotides biosynthesis, pyrimidine ribonucleotides biosynthesis and salvage as well as lipid IVA biosynthesis., Conclusion: Although LOLA had no influence on alpha and beta diversity in this nutritional model of MASLD, it was associated with changes in specific gut microbes and their related metabolic pathways., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Bats are a diverse and ecologically important group of mammals that exhibit remarkable diversity in their feeding habits. These diverse feeding habits are thought to be reflected in the composition and function of their gut microbiota, which plays important roles in nutrient acquisition, immune function, and overall health. Despite the rich biodiversity of bat species in South America, there is a lack of microbiome studies focusing on bats from this region. Such studies could offer major insights into conservation efforts and the preservation of biodiversity in South America. In this work, we aimed to compare the gut microbiota of four bat species with different feeding habits from Southern Brazil, including nectarivorous, frugivorous, insectivorous, and hematophagous bats. Our findings demonstrate that feeding habits can have a significant impact on the diversity and composition of bat gut microbiotas, with each species exhibiting unique metabolic potentials related to their dietary niches. In addition, the identification of potentially pathogenic bacteria suggests that the carriage of microbial pathogens by bats may vary, depending on feeding habits and host-specific factors. These findings provide novel insights into the relationship between bat feeding habits and gut microbiota composition, highlighting the need to promote diverse habitats and food sources to support these ecologically important species.

This comprehensive review explores the potential of using lactobacilli as a probiotic in the management of COVID-19. Our findings suggest that lactobacilli show promise in reducing the risk of death, gastrointestinal and overall symptoms, and respiratory failure, as well as in lowering cytokines and inflammatory markers associated with the disease. The molecular mechanisms by which lactobacilli protect against COVID-19 and other viral infections may be related to the reduction in inflammation, modulation of the immune response, and direct interaction with viruses to produce antiviral substances. However, the selected studies demonstrate the presence of mixed findings for various clinical, biochemical, hematological, and immunological parameters, which may be attributed to methodological differences among studies. We highlight the importance of clearly describing randomization processes to minimize bias and caution against small sample sizes and inappropriate statistical tests that could lead to errors. This review offers valuable insights into the therapeutic potential of lactobacilli in the context of COVID-19 and identifies avenues for further research and applications. These findings hold promise for the development of novel approaches to managing COVID-19 and warrant further investigation into the potential benefits of lactobacilli in combating the disease.

In this work, we examined the levels of vitamin E in the heart, liver, and kidneys of four species of adult male bats with distinct feeding habits. Our results indicate consistent vitamin E levels in the heart across all four bat species, suggesting the presence of regulatory mechanisms. Additionally, the liver displayed notably higher vitamin E levels in nectarivorous and frugivorous bats, while hematophagous bats exhibited lower levels, indicating a link between dietary intake and liver vitamin E levels. Furthermore, correlation analysis provided additional insights into the relationships between vitamin E and key antioxidant parameters in the livers of bats. On the other hand, no correlation was observed between vitamin E and key antioxidant parameters in the heart. Intriguingly, vitamin E was not detected in the kidneys, likely due to physiological factors and the prioritization of vitamin E mobilization in the heart, where it serves critical physiological functions. This unexpected absence of vitamin E in bat kidneys highlights the unique metabolic demands and prioritization of vitamin mobilization in wild animals like bats, compared to conventional animal models. These findings provide insight into the intricate distribution and utilization of vitamin E in bats, emphasizing the influence of dietary intake and metabolic adaptations on vitamin E levels in different organs.

Recent studies have shown the promising potential of probiotics, especially the bacterial genus Bifidobacterium , in the treatment of liver diseases. In this work, a systematic review was conducted, with a focus on studies that employed advanced Next Generation Sequencing (NGS) technologies to explore the potential of Bifidobacterium as a probiotic for treating liver pathologies such as Non-Alcoholic Fatty Liver Disease (NAFLD), Non-Alcoholic Steatohepatitis (NASH), Alcoholic Liver Disease (ALD), Cirrhosis, and Hepatocelullar Carcinoma (HCC) and its impact on the microbiota. Our results indicate that Bifidobacterium is a safe and effective probiotic for treating liver lesions. It successfully restored balance to the intestinal microbiota and improved biochemical and clinical parameters in NAFLD, ALD, and Cirrhosis. No significant adverse effects were identified. While more research is needed to establish its efficacy in treating NASH and HCC, the evidence suggests that Bifidobacterium is a promising probiotic for managing liver lesions.

The global pandemic was caused by the SARS-CoV-2 virus, known as COVID-19, which primarily affects the respiratory and intestinal systems and impacts the microbial communities of patients. This systematic review involved a comprehensive search across the major literature databases to explore the relationship between lactobacilli and COVID-19. Our emphasis was on investigations employing NGS technologies to explore this connection. Our analysis of nine selected studies revealed that lactobacilli have a reduced abundance in the disease and an association with disease severity. The protective mechanisms of lactobacilli in COVID-19 and other viral infections are likely to be multifaceted, involving complex interactions between the microbiota, the host immune system, and the virus itself. Moreover, upon closely examining the NGS methodologies and associated statistical analyses in each research study, we have noted concerns regarding the approach used to delineate the varying abundance of lactobacilli, which involves potential biases and the exclusion of pertinent data elements. These findings provide new insight into the relationship between COVID-19 and lactobacilli, highlighting the potential for microbiota modulation in COVID-19 treatment.

The physiopathology of liver diseases is complex and can be caused by various factors. Bifidobacterium is a bacterial genus commonly found in the human gut microbiome and has been shown to influence the development of different stages of liver diseases significantly. This study investigated the relationship between the Bifidobacterium genus and liver injury. In this work, we performed a systematic review in major databases using the key terms "Bifidobacterium", "ALD", "NAFLD", "NASH", "cirrhosis", and "HCC" to achieve our purpose. In total, 31 articles were selected for analysis. In particular, we focused on studies that used next-generation sequencing (NGS) technologies. The studies focused on assessing Bifidobacterium levels in the diseases and interventional aimed at examining the therapeutic potential of Bifidobacterium in the mentioned conditions. Overall, the abundance of Bifidobacterium was reduced in hepatic pathologies. Low levels of Bifidobacterium were associated with harmful biochemical and physiological parameters, as well as an adverse clinical outcome. However, interventional studies using different drugs and treatments were able to increase the abundance of the genus and improve clinical outcomes. These results strongly support the hypothesis that changes in the abundance of Bifidobacterium significantly influence both the pathophysiology of hepatic diseases and the related clinical outcomes. In addition, our critical assessment of the NGS methods and related statistical analyses employed in each study highlights concerns with the methods used to define the differential abundance of Bifidobacterium , including potential biases and the omission of relevant information.

The aim of this study was to compare the oxidative metabolism of four neotropical bat species with different feeding habits and investigate the relationship between their feeding habits and oxidative status. In terms of oxidative damage, our findings revealed major differences among the four bat species. In particular, hematophagous bats had lower levels of oxidative damage in the heart but higher levels in the liver. Nectarivorous bats had lower levels of carbonyl groups in the kidneys compared to insectivorous and hematophagous bats. The activity of various antioxidant and non-antioxidant enzymes in the heart, liver, and kidney also showed significant differences among the bat species. H 2 O 2 consumption was lower in the heart of hematophagous bats, while insectivorous bats exhibited the highest enzymatic activity in the kidney. SOD activity was lower in the heart of hematophagous bats and lower in nectarivorous bats in the liver. Fumarase activity was higher in the heart of frugivorous/insectivorous and lower in nectarivorous/hematophagous bats. GPx activity was higher in the heart of nectarivorous/insectivorous and higher in the kidney of insectivorous bats. GST activity was higher in the heart of nectarivorous and lower in hematophagous bats. The correlation analysis between oxidative markers and enzymatic/non-enzymatic antioxidants in the heart, liver, and kidney exhibited distinct patterns of correlations due to variations in antioxidant defense mechanisms and oxidative stress responses in different organs. The observed differences in oxidative damage, antioxidant enzyme activities, and correlations between oxidative markers and antioxidants highlight the adaptability and complexity of the antioxidant defense systems in these bats. Each organ appears to have specific demands and adaptations to cope with oxidative stress based on its physiological functions and exposure to dietary components. Our results have major significance for the conservation and management of bats, which are threatened species despite being crucial components of ecosystems. Our study's implications go beyond bat biology and offer valuable insights into comparative oxidative physiology.

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, mainly causes respiratory and intestinal symptoms and changes in the microbiota of patients. We performed a systematic search in major databases using " Bifidobacterium " and "COVID-19" or "SARS-CoV-2" as key terms to assess the relationship of the genus to COVID-19. After the selection steps, 25 articles were analyzed. Of these, eighteen were observational, and seven were interventional articles that evaluated the use of Bifidobacterium alone or in mix as probiotics for additional treatment of patients with COVID-19. All stages and severities were contemplated, including post-COVID-19 patients. Overall, Bifidobacterium was associated with both protective effects and reduced abundance in relation to the disease. The genus has been found to be abundant in some cases and linked to disease severity. The studies evaluating the use of Bifidobacterium as probiotics have demonstrated the potential of this genus in reducing symptoms, improving pulmonary function, reducing inflammatory markers, alleviating gastrointestinal symptoms, and even contributing to better control of mortality. In summary, Bifidobacterium may offer protection against COVID-19 through its ability to modulate the immune response, reduce inflammation, compete with pathogenic microbes, and maintain gut barrier function. The findings provide valuable insights into the relationship between the disease and the genus Bifidobacterium , highlighting the potential of microbiota modulation in the treatment of COVID-19.

Assessing the levels of oxidative stress markers and antioxidant enzymes in the brain is crucial in evaluating its antioxidant capacity and understanding the influence of various dietary patterns on brain well-being. This study aimed to investigate the antioxidant status and oxidative damage in the brain of bat species with different feeding habits to gain insights into their protective mechanisms against oxidative stress and their interspecific variation. The levels of oxidative damage markers and the activities of antioxidants were measured in the brain of four bat species with different feeding habits, namely insectivorous, frugivorous, nectarivorous, and hematophagous. Insectivorous bats showed higher levels of SOD and fumarase compared to the other groups, while hematophagous bats showed lower levels of these enzymes. On the other hand, the activities of glutathione peroxidase and glutathione S-transferase were higher in hematophagous bats and lower in insectivorous bats. The carbonyl groups and malondialdehyde levels were lower in frugivores, while they were similar in the other feeding guilds. Nitrite and nitrate levels were higher in the hematophagous group and relatively lower in all other groups. The GSSG/GSH ratio was higher in the hematophagous group and lower in frugivores. Overall, our results indicate that the levels of oxidative stress markers and the activities of antioxidant enzymes in the brain vary significantly among bat species with different feeding habitats. The findings suggest that the antioxidant status of the brain is influenced by diet and feeding habits.

Objectives: No specific therapy is available for metabolic dysfunction-associated fatty liver disease. We investigated nicotinamide riboside (NR) and dietary restriction (DR) effects in liver lipids, inflammation, histology, intestinal permeability, and gut microbiota in a cafeteria diet (CAFD)-induced obesity model., Methods: Adult male Wistar rats were randomly assigned to standard diet (SD) or CAFD. After 6 wk, they were subdivided into six groups-SD + vehicle (Veh) (distilled water), SD + NR (400 mg/kg), DR + Veh, DR + NR, CAFD + Veh, and CAFD + NR-for 4 wk more until euthanasia., Results: CAFD increased the hepatic content of lipids, triacylglycerols, and total cholesterol and promoted hepatomegaly, steatosis, steatohepatitis, and liver fibrosis. DR intervention successfully delayed the onset of CAFD-induced liver abnormalities except for steatosis and fibrosis. CAFD suppressed Sirt1 expression in the liver and DR increased Sirt3 expression. CAFD did not affect hepatic inflammatory genes but DR enhanced Il10 expression while decreasing Il1β expression. CAFD reduced Firmicutes and increased Bacteroidetes and Cyanobacteria, with no changes in intestinal permeability. Gut microbiota patterns in animals exposed to DR were similar to those of animals in SD. NR, specifically in CAFD, reduced hepatic triacylglycerols and total cholesterol deposition and collagen fiber accumulation in the liver and limited the colonization of CAFD-induced Cyanobacteria. NR combined with DR decreased the liver's relative weight and Tnfα expression and suppressed Sirt1 and Sirt3 hepatic expression., Conclusions: This study suggests that NR can be a potential adjuvant to metabolic dysfunction-associated fatty liver disease therapy, encouraging further research in this field., (Copyright © 2023. Published by Elsevier Inc.)

Mancozeb is a fungicide commonly used in pest control programs, especially to protect vineyards. Its toxicity has already been evidenced in several studies. However, its influence on the composition and diversity of the gut microbiota remains unknown. In this work, the adverse impact of Mancozeb on the intestinal microbiota was investigated using a rodent model. Adult male Sprague Dawley rats were randomized into three groups: Control (standard diet), MZ1 (Mancozeb dose: 250 mg/kg bw/day), and MZ2 (Mancozeb dose: 500 mg/kg bw/day). After 12 weeks of experiment, animals were euthanized, and feces present in the intestine were collected. After fecal DNA extraction, the V4 region of the 16S rRNA gene was amplified followed by sequencing in an Ion S5™ System. Alpha and beta diversity analysis showed significant differences between Control and Mancozeb groups (MZ1 e MZ2), but no difference between MZ1 and MZ2 was observed. Seven genera significantly increased in abundance following Mancozeb exposure, while five genera decreased. Co-occurrence analyses revealed that the topological properties of the microbial networks, which can be used to infer co-occurrence interaction patterns among microorganisms, were significantly lower in both groups exposed to Mancozeb when compared to Control. In addition, 23 differentially abundant microbial metabolic pathways were identified in Mancozeb-treated groups mainly related to a change in energy metabolism, LPS biosynthesis, and nucleotide biosynthesis. In conclusion, the exposure to Mancozeb presented side effects by changing the composition of the microbiota in rats, increasing bacterial diversity regardless of the dose used, reducing the interaction patterns of the microbial communities, and changing microbial metabolic pathways., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The composition of the gut microbiota oscillates according to the light-dark cycle. However, the existing literature demonstrates these oscillations only by molecular methods. Microbial cultures are an interesting method for studying metabolically active microorganisms. In this work, we aimed to understand the diurnal oscillation of the intestinal microbiota in Wistar male rats through microbial culture analysis. Over a 24 h period, three animals were euthanized every 6 h. Intestinal segments were dissected immediately after euthanasia and diluted in phosphate-buffered saline (PBS) for plating in different culture media. The CFU/mL counts in feces samples cultured in the Brucella medium were significantly higher at ZT0, followed by ZT6, ZT18, and ZT12 ( p = 0.0156), which demonstrated the diurnal oscillation of metabolically active anaerobic bacteria every 6 h using microbial culture. In addition, quantitative differences were demonstrated in anaerobic bacteria and fungi in different gastrointestinal tract tissues.

Objectives: Alcoholic liver disease (ALD) is the leading cause of alcohol-related deaths worldwide. Experimental ALD models are expensive and difficult to reproduce. A low-cost, reproducible ALD model was developed, and liver damage compared with the gut microbiota. The aims of this study were to develop an experimental model of ALD, through a high-fat diet, the chronic use of ethanol, and intragastric alcohol binge; and to evaluate the composition of the gut microbiota and its correlation with markers of inflammatory and liver disease progression in this model., Methods: Adult male Wistar rats were randomized (N = 24) to one of three groups: control (standard diet and water + 0.05% saccharin), ALC4 and ALC8 (sunflower seed, 10% ethanol + 0.05% saccharin for 4 and 8 wk, respectively). On the last day, ALC4/8 received alcoholic binge (5 g/kg). Clinical, nutritional, biochemical, inflammatory, pathologic, and gut microbiota data were analyzed., Results: ALC4/8 animals consumed more alcohol and lipids (P < 0.01) and less total energy, liquids, solids, carbohydrates, and proteins (P < 0.01), and gained less weight (P < 0.01) than controls. ALC8 had lower Lee index scores than controls and ALC4 (P < 0.01). Aminotransferases increased and albumin diminished in ALC4/8 but not in the control group (P < 0.03 for all). Glucose and aspartate transaminase/alanine aminotransaminase ratios were higher in the ALC8 rats than in the controls (P < 0.03). Cholesterol was higher in ALC4 and lower in ALC8 compared with controls (P < 0.03). Albumin and high-density lipoprotein cholesterol levels were lower in ALC8 (P < 0.03). Hepatic concentration of triacylglycerols was higher in ALC8 than in ALC4 and controls (P < 0.05). ALC4/8 presented microvesicular grade 2 and 3 steatosis, respectively, and macrovesicular grade 1. No change in the gene expression of inflammatory markers between groups was seen. ALC4/8 had lower fecal bacterial α-diversity and relative abundance of Firmicutes (P < 0.005) and greater Bacterioidetes (P < 0.0007) and Protobacteria (P < 0.001) than controls. Gut microbiota correlated with serum and liver lipids, steatosis, albumin, and aminotransferases (P < 0.01 for all)., Conclusion: The model induced nutritional, biochemical, histologic, and gut microbiota changes, and appears to be useful in the study of therapeutic targets., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Unlike most animals, most bats cannot synthesize vitamin C endogenously. Consequently, this vitamin must be obtained from the diet. Among the bat species, there are several food groups, such as frugivorous, nectarivorous, insectivorous, and hematophagous. In this work, we measured and compared vitamin C levels in different organs of four species of bats, all collected in southern Brazil. When analyzing and comparing the levels of vitamin C in the four bat species, (regardless of the organ), no significant differences were observed. However, when analyzing and comparing the levels of vitamin C in the four organs (regardless of the species), significant differences were observed, with the highest concentrations in the heart, followed by the liver and brain, while the lowest concentration was measured in the kidneys. Additional differences in the levels of Vitamin C were only observed when each organ was analyzed according to the species/diet. These results indicate a high degree of metabolic homeostasis in bats despite the marked difference in the type of diet.

A prospective study was conducted to identify bacterial communities in the nasal and laryngeal cavities of pigs with or without clinical signs of respiratory disease in a longitudinal fashion, from weaning to the finishing phase. Nasal and laryngeal swabs were collected from asymptomatic pigs (n = 30), as well as from pigs with clinical signs of respiratory disease (n = 30) at the end of the weaning (T1-33 days) phase, end of the nursery phase (T2-71 days), and finishing (T3-173 days). Total DNA was extracted from each sample, and the V4 hypervariable region of the 16S rRNA gene was amplified and sequenced with the Illumina MiSeq platform. Principal coordinates analysis indicated no significant differences between the nasal and laryngeal bacterial communities. Nevertheless, the microbiota composition in the upper respiratory tract (URT) was clearly distinct between animals, with or without signs of respiratory disease, particularly at post-weaning and the end of nursery. In pigs with clinical signs of respiratory disease, Actinobacillus , Streptococcus Porphyromonas , Veillonella , and an unclassified genus of Pasteurellaceae were more abundant than in pigs with no signs. Metabolic prediction identified 28 differentially abundant pathways, mainly related to carbohydrate, energy, amino acid, anaerobic, and nucleotide metabolism in symptomatic pigs (especially in T2). These findings provide evidence that the composition of the URT bacterial microbiota differs significantly when comparing pigs with or without respiratory clinical signs after weaning, and this difference is maintained in the nursery phase; such differences, however, were not evident at the finishing phase.

Background: Cardiovascular disease is the main cause of death in metabolic-associated fatty liver disease, and gut microbiota dysbiosis is associated with both of them., Aim: To assess the relationship between gut dysbiosis and cardiovascular risk (CVR) in an experimental model of steatohepatitis., Methods: Adult male Sprague-Dawley rats were randomized to a control group ( n = 10) fed a standard diet and an intervention group ( n = 10) fed a high-fat choline-deficient diet for 16 wk. Biochemical, molecular, hepatic, and cardiac histopathology. Gut microbiota variables were evaluated., Results: The intervention group had a significantly higher atherogenic coefficient, Castelli's risk index (CRI)-I and CRI-II, interleukin-1β, tissue inhibitor of metalloproteinase-1 (all P < 0.001), monocyte chemoattractant protein-1 ( P = 0.005), and plasminogen activator inhibitor-1 ( P = 0.037) than the control group. Gene expression of miR-33a increased ( P = 0.001) and miR-126 ( P < 0.001) decreased in the intervention group. Steatohepatitis with fibrosis was seen in the intervention group, and heart computerized histological imaging analysis showed a significant decrease in the percentage of cardiomyocytes with a normal morphometric appearance ( P = 0.007), reduction in the mean area of cardiomyocytes ( P = 0.037), and an increase of atrophic cardiomyocytes ( P = 0.007). There were significant correlations between the cardiomyocyte morphometry markers and those of progression and severity of liver disease and CVR. The intervention group had a lower Shannon diversity index and fewer changes in the structural pattern of gut microbiota (both P < 0.001) than controls. Nine microbial families that are involved in lipid metabolism were differentially abundant in intervention group and were significantly correlated with markers of liver injury and CVR., Conclusion: The study found a link between gut dysbiosis and significant cardiomyocyte abnormalities in animals with steatohepatitis., Competing Interests: Conflict-of-interest statement: The authors declare that they have no competing interests., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

Aim: To assess in a cross-sectional clinical study the effect of antibiotics on the diversity, structure and metabolic pathways of bacterial communities in various oral environments in patients with acute primary infections., Methodology: Samples of saliva (SA), supragingival biofilm (SB) and from the pulp cavity (PC) were collected from teeth with acute primary infections and then grouped according to previous use of antibiotics (NoAtb = no antibiotics [n = 6]; Atb = antibiotics [n = 6]). DNA sequencing was conducted using MiSeq (Illumina, San Diego, CA, USA). The V1-V3 hyper-variable region of the 16S rRNA gene was amplified. A custom Mothur pipeline was used for 16S rRNA processing. Subsequent analyses of the sequence dataset were performed in R (using vegan, phyloseq and ggplot2 packages) or QIIME., Results: Twelve patients aged from 22 to 56 years were recruited. Participants in the Atb group had taken the beta-lactamics amoxicillin (5/6) or cephalexin (1/6) for 2-3 days. A total of 332 bacterial taxa (OTUs) were identified, belonging to 120 genera, 60 families and nine phyla. Firmicutes (41%) and Bacteroidetes (38%) were the most abundant phyla in all samples. Taxa clustered significantly by oral site (PCoA analysis; P < 0.05, ANOSIM). Use of antibiotics had little effect on this clustering. However, SA, SB and PC had different degrees of richness, diversity and evenness. The greatest diversity was observed in SB samples and the least diversity was observed in PC samples. Metabolic prediction identified 163 pathways and previous use of antibiotics had a major effect on the estimated functional clustering in SA and PC samples., Conclusion: The ecological niche had a strong influence on the bacterial content of samples from various oral sites. Previous exposure to antibiotics may exert an effect on the phylogenetic composition of SA. Metabolic pathways appear to be modulated by antimicrobial agents in SA and PC samples. The dynamics of host/microbial interactions in the apical region and the functional ecology of the infected pulp cavity should be revisited., (© 2020 International Endodontic Journal. Published by John Wiley & Sons Ltd.)

Background/aim: The interactions between the gut and liver have been described in the progression of non-alcoholic steatohepatitis (NASH). The aim of this study was to develop an experimental nutritional model of NASH simulating metabolic changes occurring in humans., Materials and Methods: Adult male Sprague Dawley rats were randomized into two groups: controls (standard diet) and intervention (high-fat and choline-deficient diet) for 16 weeks, each experimental group with 10 animals. Biochemical analysis, hepatic lipid content, microRNAs, inflammatory, gut permeability markers and gut microbiota were measured., Results: Animals in the intervention group showed significantly higher delta Lee index ( p =0.017), abdominal circumference ( p <0.001), abdominal adipose tissue ( p <0.001) and fresh liver weight ( p <0.001), as well as higher serum levels of alanine aminotransferase ( p =0.010), glucose ( p =0.013), total cholesterol ( p =0.033), LDL cholesterol ( p =0.011), and triglycerides ( p =0.011), and lower HDL cholesterol ( p =0.006) compared to the control group. Higher TLR4 ( p =0.041), TLR9 ( p =0.033), MyD88 ( p =0.001), Casp1 ( p <0.001), NLPR3 ( p =0.019), liver inflammation index interleukin (IL)-1β/IL10 ( p <0.001), IL6/IL10 ( p =0.002) and TNFα/IL10 ( p =0.001) were observed in the intervention group, and also lower permeability markers Ocln ( p =0.003) and F11r ( p =0.041). Gene expression of miR-122 increased ( p =0.041) and miR-145 ( p =0.010) decreased in the intervention group. Liver steatosis, inflammation and fibrosis, along with collagen fiber deposition increment ( p <0.001), were seen in the intervention group. Regarding gut microbiota, Bray-Curtis dissimilarity index and number of operational taxonomic units were significantly different ( p <0.001) between the groups. Composition of the gut microbiota showed a significant correlation with histopathological score of NAFLD (r=0.694) and index IL-1β/IL-10 (r=0.522)., Conclusion: This experimental model mimicking human NASH demonstrated gut and liver interaction, with gut microbiota and intestinal permeability changes occurring in parallel with systemic and liver inflammation, miRNAs regulation and liver tissue damage., Competing Interests: The authors report no conflicts of interest in this work., (© 2020 Longo et al.)

The aim of this work was to analyze and compare the bacterial communities of 663 samples from a Brazilian hospital by using high-throughput sequencing of the 16S rRNA gene. To increase taxonomic profiling and specificity of 16S-based identification, a strict sequence quality filtering process was applied for the accurate identification of clinically relevant bacterial taxa. Our results indicate that the hospital environment is predominantly inhabited by closely related species. A massive dominance of a few taxa in all taxonomic levels down to the genera was observed, where the ten most abundant genera in each facility represented 64.4% of all observed taxa, with a major predominance of Acinetobacter and Pseudomonas . The presence of several nosocomial pathogens was revealed. Co-occurrence analysis indicated that the present hospital microbial network had low connectedness, forming a clustered topology, but not structured among groups of nodes (i.e., modules). Furthermore, we were able to detect ecologically relevant relationships between specific microbial taxa, in particular, potential competition between pathogens and non-pathogens. Overall, these results provide new insight into different aspects of a hospital microbiome and indicate that 16S rRNA sequencing may serve as a robust one-step tool for microbiological identification and characterization of a wide range of clinically relevant bacterial taxa in hospital settings with a high resolution.

Production and emission of CO 2 from different sources have caused significant changes in the climate, which is the major concern related to global warming. Among other CO 2 removal approaches, microalgae can efficiently remove CO 2 through the rapid production of algal biomass. In addition, microalgae have the potential to be used in wastewater treatment. Although, wastewater treatment and CO 2 removal by microalgae have been studied separately for a long time, there is no detailed information available on combining both processes. In this review article, microalgae-based CO 2 biofixation, various microalgae cultivation systems,¯ and microalgae-derived wastewater treatment are separately discussed, followed by the concept of integration of CO 2 biofixation process and wastewater treatment. In each section, details of energy efficiency and differences across microalgae species are also given.

Next-generation, culture-independent sequencing offers an excellent opportunity to examine network interactions among different microbial species. In this study, soil bacterial communities from a penguin rookery site at Seymour Island were analyzed for abundance, structure, diversity, and interaction networks to identify interaction patterns among the various taxa at three soil depths. The analysis revealed the presence of eight phyla distributed in different proportions among the surface layer (0-8 cm), middle layer (20-25 cm), and bottom (35-40 cm). The bottom layer presented the highest values of bacterial richness, diversity, and evenness when compared to surface and middle layers. The network analysis revealed the existence of a unique pattern of interactions in which the soil microbial network formed a clustered topology, rather than a modular structure as is usually found in biological communities. In addition, specific taxa were identified as important players in microbial community structure. Furthermore, simulation analyses indicated that the loss of potential keystone groups of microorganisms might alter the patterns of interactions within the microbial community. These findings provide new insights for assessing the consequences of environmental disturbances at the whole-community level in Antarctica.

One year after I assumed the position of Editor in Chief of Life, it is my great pleasure to write this editorial highlighting our achievements during this period, which were so many! As I wrote in the first editorial, my commitment was to make the journal a success, with the launch of exciting special issues, publication of high quality papers as well as inclusion of the journal in major indexing and abstracting services [1]. Basically, throughout 2014, all these commitments have been accomplished. Several eminent team leaders have joined our editorial board [2], timely special issues have been launched [3], and the journal already was indexed in PubMed [4]; now, it is just a matter of time to be indexed in Web of Science. The feedback from the scientific community already has been quite positive. With timely special issues lined up for 2015, the journal is developing quite fast.[...].

Platelets are cytoplasmatic fragments from bone marrow megakaryocytes present in blood. In this work, we review the basis of platelet mechanisms, their participation in syndromes and in arterial thrombosis, and their potential as a target for designing new antithrombotic agents. The option of new biotechnological sources is also explored.

Nitric oxide (NO) is one of the most important vasodilator molecules produced by the endothelium. It has already been established that NO/cGMP signaling pathway deficiencies are involved in the pathophysiological mechanisms of many cardiovascular diseases. In this context, the development of NO-releasing drugs for therapeutic use appears to be an effective alternative to replace the deficient endogenous NO and mimic the role of this molecule in the body. Organic nitrates represent the oldest class of NO donors that have been clinically used. Considering that tolerance can occur when these drugs are applied chronically, the search for new compounds of this class with lower tolerance potential is increasing. Here, we briefly discuss the mechanisms involved in nitrate tolerance and highlight some achievements from our group in the development of new organic nitrates and their preclinical application in cardiovascular disorders.

As an advocate of the transparency on the peer review process, during the last months, I've been working with MDPI to implant a new system of open peer review, under which the peer-review reports and authors' responses are published as an integral part of the final version of each article. This new model of publishing associated with the open access platform of MDPI result in one of the most transparent, unbiased, democratic and reliable assessment of research currently available. Life is the first MDPI journal to make this courageous step towards open peer-review in order to demonstrate the rigorous, fair and efficient standard of our editorial work. The first paper published under this new policy was a manuscript written by a Nobelist and reviewed by three experts in the field, as highlighted in this editorial.

It is my great pleasure to serve as the new Editor-in-Chief of Life, a journal concerned with fundamental questions on the origins and nature of life, evolution of biosystems and astrobiology. With my experience as Executive Editor, Senior Editor and Guest Editor of so many successful special issues (some of them in MDPI journals [1-6]), I am committed to making the journal a success, with the launch of exciting special issues, publication of high quality papers, as well as inclusion of the journal in major indexing and abstracting services. In this editorial, I present my view and plans for the journal. [...].

The Brazilian Savanna, also known as "Cerrado", is the richest and most diverse savanna in the world and has been ranked as one of the main hotspots of biodiversity. The Cerrado is a representative biome in Central Brazil and the second largest biome in species diversity of South America. Nevertheless, large areas of native vegetation have been converted to agricultural land including grain production, livestock, and forestry. In this view, understanding how land use affects microbial communities is fundamental for the sustainable management of agricultural ecosystems. The aim of this work was to analyze and compare the soil bacterial communities from the Brazilian Cerrado associated with different land use systems using high throughput pyrosequencing of 16S rRNA genes. Relevant differences were observed in the abundance and structure of bacterial communities in soils under different land use systems. On the other hand, the diversity of bacterial communities was not relevantly changed among the sites studied. Land use systems had also an important impact on specific bacterial groups in soil, which might change the soil function and the ecological processes. Acidobacteria, Proteobacteria, and Actinobacteria were the most abundant groups in the Brazilian Cerrado. These findings suggest that more important than analyzing the general diversity is to analyze the composition of the communities. Since soil type was the same among the sites, we might assume that land use was the main factor defining the abundance and structure of bacterial communities.

Over the last decades, the study of extremophiles has providing ground breaking discoveries that challenge the paradigms of modern biology and make us rethink intriguing questions such as "what is life?", "what are the limits of life?", and "what are the fundamental features of life?". These findings and possibilities have made the study of life in extreme environments one of the most exciting areas of research in recent decades. However, despite the latest advances we are just in the beginning of exploring and characterizing the world of extremophiles. This special issue discusses several aspects of these fascinating organisms, exploring their habitats, biodiversity, ecology, evolution, genetics, biochemistry, and biotechnological applications in a collection of exciting reviews and original articles written by leading experts and research groups in the field. [...].

The Europa Jupiter System Mission (EJSM) is the major Outer Planet Flagship Mission in preparation by NASA. Although well designed, the current EJSM concept may present problematic issues as a Flagship Mission for a long-term exploration program that will occur over the course of decades. For this reason, the present work reviews the current EJSM concept and presents a new strategy for the exploration of Europa. In this concept, the EJSM is reorganized to comprise three independent missions focused on Europa. The missions are split according to scientific goals, which together will give a complete understanding of the potential habitability of Europa, including in situ life's signal measurements. With this alternative strategy, a complete exploration of Europa would be possible in the next decades, even within a politically and economically constrained environment.