Sodium butyrate attenuates peritoneal fibroproliferative process in mice.

NEW FINDINGS: What is the central question of this study? Peritoneal injury can result in a persistent fibroproliferative process in the abdominal cavity, causing pain and loss of function of internal organs. This study aimed to demonstrate the use of sodium butyrate (NaBu) as a potential agent to attenuate peritoneal fibrosis induced by a synthetic matrix. What is the main finding and its importance? Our findings provide the first evidence that NaBu attenuates the inflammatory, angiogenesis and fibrogenesis axes involved in the formation of peritoneal fibrovascular tissue, indicating the potential of this compound to ameliorate peritoneal fibrosis. ABSTRACT: The aim of this study was to identify the bio-efficacy of sodium butyrate (NaBu) on preventing the development of peritoneal fibrovascular tissue induced by implantation of a synthetic matrix in the abdominal cavity. Polyether-polyurethane sponge discs were implanted in the peritoneal cavity of mice, which were treated daily with oral administration of NaBu (100 mg/kg). Control animals received water (100 µl). After 7 days, the implants were removed for assessment of inflammatory, angiogenic and fibrogenic markers. Compared with control values, NaBu treatment decreased mast cell recruitment/activation, inflammatory enzyme activities, levels of pro-inflammatory cytokines, and the proteins p65 and p50 of the nuclear factor-κB pathway. Angiogenesis, as determined by haemoglobin content, vascular endothelial growth factor levels and the number of blood vessels in the implant, was reduced by the treatment. In NaBu-treated animals, the predominant collagen present in the abdominal fibrovascular tissue was thin collagen, whereas in control implants it was thick collagen. Transforming growth factor-ß1 levels were also lower in implants of treated animals. Sodium butyrate downregulated the inflammatory, angiogenesis and fibrogenesis axes of the fibroproliferative tissue induced by the intraperitoneal synthetic matrix. This compound has potential to control/regulate chronic inflammation and adverse healing processes in the abdominal cavity.

Correlation between circadian rhythm related genes, type 2 diabetes, and cancer: Insights from metanalysis of transcriptomics data.

Clock genes work as an auto-regulated transcription-translational loop of circadian genes that drives the circadian rhythms in each cell and they are essential to physiological requests. Since metabolism is a dynamic process, it involves several physiological variables that circadian cycling. The clock genes alterations can affect multiple systems concomitantly, because they constitute the promoter factors for relevant metabolic pathways. Considering the intertwined structure of signaling, regulatory, and metabolic processes within a cell, we employed a genome-scale biomolecular network. Accordingly, a meta-analysis of diabetic-associated transcriptomic datasets was performed, and the core information on differentially expressed genes (DEGs) was obtained by statistical analyses. In the current study, meta-analysis was performed on type 2 diabetes, circadian rhythm-related genes, and breast, bladder, liver, pancreas, colon and rectum cancer-associated transcriptome data using the integration of gene expression profiles with genome-scale biomolecular networks in diabetes samples. First, we detected downregulated and upregulated DEGs in mouse cortex and hypothalamus samples of mice with sleep deprivation. In summary, upregulated genes active genes associated with oxidative phosphorylation, cancer and diabetes, mainly in hypothalamus specimens. In cortex, we observed mainly downregulation of immune system. DEGs were combined with 214 circadian rhythm related genes to type 2 DM and cancer samples. We observed that several common genes deregulated in both diseases. Klf10, Ntkr3, Igf1, Usp2, Ezh2 were both downregulated in type 2 DM and cancer samples, while Arntl2 and Agrp were upregulated. It seems that the changes in mRNA are contributing to the phenotypic changes in type 2 DM, resulting in phenotypic changes associated with the malignant transformation. Taking those genes to perform a survival analysis, we found only Igf1, Usp2 and Arntl2 genes associated with patient outcomes. While Igf1 and Usp2 downregulation had a negative impact, Arntl2 upregulation was associated with poor survival both in BLCA and BRCA cancer samples. Our data stimulate efforts in news studies to achieve the experimental and clinical validation about these biomolecules.

Factors Associated with Mortality among Hospitalized Patients with COVID-19: A Retrospective Cohort Study.

Information on the risk factors for COVID-19 mortality in low- and middle-income countries is still scarce. In this retrospective cohort study, we analyzed the factors associated with COVID-19 mortality in hospitalized patients in a poor area of Brazil. Logistic regression was used to identify factors independently associated with mortality, including gender, age, and the presence of underlying medical conditions. A total of 1,207 patients were included in the analysis, and a 1.5-fold increase in COVID-19 mortality was found among patients aged > 65 years with hypertension and diabetes (odds ratio [OR]: 1.50, 95% CI: 1.02-2.19). Moreover, infectious disease (OR: 4.31, 95% CI: 1.39-13.39), kidney disease (OR: 2.59, 95% CI: 1.27-5.27), and heart disease (OR: 2.00, 95% CI: 1.31-3.04) were also predictive for COVID-19 in-hospital death. This large cohort provides important data on potential factors associated with COVID-19 mortality in Brazil.

Implant-induced inflammatory angiogenesis is up-regulated in obese mice.

The damaging effects of obesity extend to multiple pre-existing tissue/organs. However, the influence of this condition on key components (inflammation and angiogenesis) of fibrovascular connective proliferating tissue, essential in repair processes, has been neglected. Our objective in this study was to investigate whether obesity would influence inflammatory-angiogenesis induced by synthetic matrix of polyether-polyurethane implanted subcutaneously in high-fat-fed obese C57/BL6 mice. Fourteen days after implantation, the inflammatory and angiogenic components of the newly formed tissue intra-implant were evaluated. The pro-inflammatory enzyme activities, myeloperoxidase (MPO) and N-acetyl-ß-D-glucosaminidase (NAG), the levels of TNF-α, CXCL1/KC and CCL2 and NF-κB transcription factor were examined. Angiogenesis was determined by morphometric analysis of implant blood vessels, intra-implant levels of hemoglobin content, VEGF levels, and western blot for VEGFR2. All inflammatory and angiogenic markers were increased in the implants of obese mice compared with their non-obese counterparts. Similarly, activation of the NF-κB pathway and phosphorylation of VEGFR2 were higher in implants of obese mice (1.60 ± 0.28 Np65/Cp65; 0.96 ± 0.08 p-VEGFR2/VEGFR2-T) compared with implants of non-obese animals (1.40 ± 0.14; 0.49 ± 0.08). These observations suggest that obesity exerts critical role in sponge-induced inflammatory-angiogenesis, possibly by activating fibrovascular components in the inflamed microenvironment. Thus, this pathological condition causes damage not only to pre-existing tissues/organs but also to newly formed proliferating fibrovascular tissue. This is relevant to the development of therapeutic approaches to improve healing processes in patients with obesity.

Sodium Butyrate Downregulates Implant-Induced Inflammation in Mice.

Sodium butyrate (NaBu), a histone deacetylase inhibitor, has shown to exert beneficial actions attenuating inflammation in a number of intestinal and extra-intestinal diseases. However, the effects of NaBu on persistent inflammatory processes as in a response to implantation of foreign material have not been investigated. Synthetic matrix of polyether-polyurethane sponge was implanted in mice's subcutaneous layer of the dorsal region, and the animals were treated daily with oral administration of NaBu (100 mg/kg). After 7 days, the implants were removed and processed for assessment of inflammatory markers. Butyrate treatment caused a significant attenuation of neutrophil and macrophage infiltration in implants, which was reflected by the reduction of myeloperoxidase and N-acetyl-ß-D-glucosaminidase activities, respectively. Similar reduction was observed in intra-implants nitrite levels of NaBu-treated mice. NaBu treatment was also able to decrease mast cell recruitment/activation and the levels of CXCL1, CCL2, IL-6, TNF-ɑ, and TGF-ß1 in the implants but did not alter the levels of IL-10. In addition, NaBu administration decreased the concentration of proteins p65 and p50 in the nucleus as compared with the cytoplasm by western blot analysis. This result suggests that treatment with NaBu inhibited the NF-κB pathway. The circulating levels of TNF-ɑ and TGF-ß1 were also attenuated by NaBu. Persistent inflammation at sites of implanted devices very often impairs their functionality; therefore, our findings suggest that NaBu holds potential therapeutic value to control this adverse response to biomedical implants.

Correlation between renin-angiotensin system (RAS) related genes, type 2 diabetes, and cancer: Insights from metanalysis of transcriptomics data.

Although studies have provided significant evidence about the role of RAS in mediating cancer risk in type 2 diabetes mellitus (DM), conclusions about the central molecular mechanisms underlying this disease remain to be reached, because this type of information requires an integrative multi-omics approach. In the current study, meta-analysis was performed on type 2 diabetes and breast, bladder, liver, pancreas, colon and rectum cancer-associated transcriptome data, and reporter biomolecules were identified at RNA, protein, and metabolite levels using the integration of gene expression profiles with genome-scale biomolecular networks in diabetes samples. This approach revealed that RAS biomarkers could be associated with cancer initiation and progression, which include metabolites (particularly, aminoacyl-tRNA biosynthesis and ABC transporters) as novel biomarker candidates and potential therapeutic targets. We detected downregulation and upregulation of differentially expressed genes (DEGs) in blood, pancreatic islets, liver and skeletal muscle from normal and diabetic patients. DEGs were combined with 211 renin-angiotensin-system related genes. Upregulated genes were enriched using Pathway analysis of cancer in pancreatic islets, blood and skeletal muscle samples. It seems that the changes in mRNA are contributing to the phenotypic changes in carcinogenesis, or that they are as a result of the phenotypic changes associated with the malignant transformation. Our analyses showed that Ctsg and Ednrb are downregulated in cancer samples. However, by immunohistochemistry experiments we observed that EDNRB protein showed increased expression in tumor samples. It is true that alterations in mRNA expression do not always reflect alterations in protein expression, since post-translational changes can occur in proteins. In this study, we report valuable data for further experimental and clinical analysis, because the proposed biomolecules have significant potential as systems biomarkers for screening or for therapeutic purposes in type 2 diabetes and cancer-associated pathways.

Schwann cell reprogramming and lung cancer progression: a meta-analysis of transcriptome data.

Schwann cells were identified in the tumor surrounding area prior to initiate the invasion process underlying connective tissue. These cells promote cancer invasion through direct contact, while paracrine signaling and matrix remodeling are not sufficient to proceed. Considering the intertwined structure of signaling, regulatory, and metabolic processes within a cell, we employed a genome-scale biomolecular network. Accordingly, a meta-analysis of Schwann cells associated transcriptomic datasets was performed, and the core information on differentially expressed genes (DEGs) was obtained by statistical analyses. Gene set over-representation analyses was performed on core DEGs to identify significantly functional and pathway enrichment analysis between Schwann cells and, lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). DEGs were further integrated with genome-scale human biomolecular networks. miRNAs were proposed by the reconstruction of a transcriptional and post-transcriptional regulatory network. Moreover, microarray-based transcriptome profiling was performed, and the prognostic power of selected dedifferentiated Schwann cell biomolecules was predicted. We observed that pathways associated with Schwann cells dedifferentiation was overexpressed in lung cancer samples. However, genes associated with Schwann cells migration inhibition system were downregulated. Besides, miRNA targeting those pathways were also deregulated. In this study, we report valuable data for further experimental and clinical analysis, because the proposed biomolecules have significant potential as systems biomarkers for screening or for therapeutic purposes in perineural invasion of lung cancer.

Double immunofluorescence labeling for CD31 and CD105 as a marker for polyether polyurethane-induced angiogenesis in mice.

A crucial component of the integration between foreign implants and the host is angiogenesis. However, to date, none of the available techniques and/or endothelial markers employed to assess angiogenesis in the implant/host interface seems to be able to highlight vascular structures convincingly. In the present study we investigated and compared the expression of two endothelial cell markers: platelet endothelial cell adhesion molecule (PECAM-1) (CD31) and endoglin (CD105) using immunohistochemistry (IHC) and immunofluorescence (IF) to identify and quantify newly formed blood vessels in subcutaneous implants of polyether-polyurethane sponge of formalin-fixed paraffin-embedded tissue. At day 14 post implantation the discs of the synthetic matrix were removed and processed for histological and morphometric analysis. In IHC staining for CD31 antibody the number of vessels was 2.27±0.69 and 5.25±0.46 for CD105. In IF for CD31 the number of vessels was 15.36±1.295 and 10.54±0.8213 for CD105. The level of cross-reaction was lesser in IF images compared with IHC images. Co-localization of CD31/CD105 using confocal images showed positive correlation (Pearson's co-relation and Manders' equation). The double labeling for blood vessels using the IF technique for CD31/CD105 may be an important tool for evaluation of angiogenesis in biomaterial/host integration.

Cytokine Production Is Differentially Modulated in Malignant and Non-malignant Tissues in ST2-Receptor Deficient Mice.

IL-33/ST2 axis has been shown to exert both pro- and anti- effects in wound healing and tumor development. To further understand the role of this cytokine complex, we characterized comparatively the inflammatory component of a malignant tissue and non-malignant tissue in mice lacking ST2 receptor (ST2-KO). KO mice and their wild-type (WT) counterparts were either implanted subcutaneously with polyether-polyurethane sponge discs to induce non-malignant fibrovascular tissue growth or inoculated with 4T1 cells to induce mammary tumor. Loss of ST2 receptor in mice resulted in enhanced mammary tumor and fibrovascular tissue relative to the WT animals. The inflammatory parameters (MPO and NAG activities, levels of the cytokines CXCL1/KC, CCL2, TNF-α, TGF-ß1, and mast cell number) were differentially modulated in both tissues. In tumors, these parameters were, overall, lower compared with those in tumors of WT mice. In KO implants, CXCL1/KC and TNF-α levels increased; MPO, NAG, and CCL2 levels decreased relative to the WT implants. In addition, deletion of ST2 receptor inhibited mast cell recruitment but had no effect on TGF-ß1 levels in implants. Our study has shown antitumorigenic effect of ST2 in mammary tumor and this may be mediated by downregulation of pro-inflammatory cytokines (CXCL1/KC, CCL2, TNF-α, and TGF-ß1). Conversely, in the fibrovascular tissue, lack of ST2 receptor resulted in differential modulation of cytokine production. Differential signaling mechanisms may be activated by IL-33/ST2 axis to modulate cytokine production in malignant and non-malignant proliferative processes.

Upregulation of Foreign Body Response in Obese Mice.

OBJECTIVE: Obesity is a highly prevalent multifactorial metabolic condition in which the need for functional bioengineered substitutes (e.g., scaffolds for tissue engineering) is likely to occur. However, the adverse foreign body response (FBR) that invariably takes place adjacent to implant devices impairing their function is poorly characterized in this condition. This study investigated the influence of obesity on the host response to a synthetic matrix implanted subcutaneously in high-fat-fed obese mice. METHODS: Histological analysis of 14-day-old implants was performed to identify collagen deposition, capsule thickness, fibroblast-like cells, foreign body giant cells, and mast cells. In addition, transforming growth factor ß1 (TGF-ß1) levels in the implants and serum were determined. RESULTS: All fibrogenic markers (and TGF-ß1 levels) increased in the implants of obese mice compared with their nonobese counterparts. Particularly relevant was the fibrous capsule thickness in implants of obese mice (234.2 ± 22.1 µm vs. 109.2 ± 13.4 µm in implants of nonobese animals). CONCLUSIONS: The study results showing that obesity upregulates the main features of the FBR induced by subcutaneous implants in mice may be relevant in understanding biomaterial integration and performance in this condition. This is crucial to the development of strategies to maintain the integrity and function of implantable devices.