Homocysteine Aggravates Intestinal Epithelial Barrier Dysfunction in Rats with Experimental Uremia

Background/Aims: Previous studies have shown that homocysteine (Hcy) is an important intestinal-derived uremic toxin. However, whether Hcy is involved in the epithelial barrier dysfunction observed in uremia remains unclear. This study aimed to investigate the effect of Hcy on intestinal permeability and intestinal barrier structure and function in adenine-induced uremic rats. Methods: Sprague-Dawley rats were divided into five groups: normal control (group NC), Hcy (group H), uremia (group U), uremia + Hcy (group UH), and uremia + Hcy + VSL#3 (group UHV). Experimental uremia was induced by intragastric adenine administration, and Hcy was injected subcutaneously. The animal models were assessed for renal function and pathological tissue staining. The pathological changes of intestinal tissue were observed by hematoxylin and eosin staining and electron microscopy. The serum and intestinal tissue levels of Hcy, interleukin (IL)-6, tumor necrosis factor (TNF)-α, superoxide dismutase (SOD), and malondialdehyde (MDA) as well as serum endotoxin and intestinal permeability were assessed. The levels of the tight junction proteins claudin-1, occludin, and zonula occludens-1 (ZO-1) were assessed by western blotting. Results: Blood analyses and renal pathology indicated that experimental uremia was induced successfully. Pathological damage to intestinal structure was most obvious in group UH. Serum and tissue Hcy, serum endotoxin, and intestinal permeability were significantly elevated in group UH. The protein levels of claudin-1, occludin, and ZO-1 were decreased to various degrees in group UH compared with groups NC, H, and U. The serum and tissue levels of IL-6, TNF-α, and MDA were significantly increased, while SOD activity was markedly decreased. Supplementation with the probiotic VSL#3 improved these parameters to various degrees and up-regulated the abundance of tight junction proteins, which indicated a role for Hcy in the increase of intestinal permeability and destruction of the epithelial barrier in uremia. Conclusion: Hcy aggravates the increase of intestinal permeability and destruction of the epithelial barrier by stimulating inflammatory and oxidative damage. Probiotic administration can ameliorate this damage by reducing the levels of Hcy-induced inflammation and oxidation

Downregulation of TGF-beta receptor types II and III in oral squamous cell carcinoma and oral carcinoma-associated fibroblasts

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to assess the expression levels for TβRI, TβRII, and TβRIII in epithelial layers of oral premalignant lesions (oral leukoplakia, OLK) and oral squamous cell carcinoma (OSCC), as well as in oral carcinoma-associated fibroblasts (CAFs), with the final goal of exploring the roles of various types of TβRs in carcinogenesis of oral mucosa.</p> <p>Methods</p> <p>Normal oral tissues, OLK, and OSCC were obtained from 138 previously untreated patients. Seven primary human oral CAF lines and six primary normal fibroblast (NF) lines were established successfully via cell culture. The three receptors were detected using immunohistochemical (IHC), quantitative RT-PCR, and Western blot approaches.</p> <p>Results</p> <p>IHC signals for TβRII and TβRIII in the epithelial layer decreased in tissue samples with increasing disease aggressiveness (P < 0.05); no expression differences were observed for TβRI, in OLK and OSCC (P > 0.05); and TβRII and TβRIII were significantly downregulated in CAFs compared with NFs, at the mRNA and protein levels (P < 0.05). Exogenous expression of TGF-β1 led to a remarkable decrease in the expression of TβRII and TβRIII in CAFs (P < 0.05).</p> <p>Conclusion</p> <p>This study provides the first evidence that the loss of TβRII and TβRIII expression in oral epithelium and stroma is a common event in OSCC. The restoration of the expression of TβRII and TβRIII in oral cancerous tissues may represent a novel strategy for the treatment of oral carcinoma.</p

New insights into the role of immunity and inflammation in diabetic kidney disease in the omics era

Diabetic kidney disease (DKD) is becoming the leading cause of chronic kidney disease, especially in the industrialized world. Despite mounting evidence has demonstrated that immunity and inflammation are highly involved in the pathogenesis and progression of DKD, the underlying mechanisms remain incompletely understood. Substantial molecules, signaling pathways, and cell types participate in DKD inflammation, by integrating into a complex regulatory network. Most of the studies have focused on individual components, without presenting their importance in the global or system-based processes, which largely hinders clinical translation. Besides, conventional technologies failed to monitor the different behaviors of resident renal cells and immune cells, making it difficult to understand their contributions to inflammation in DKD. Recently, the advancement of omics technologies including genomics, epigenomics, transcriptomics, proteomics, and metabolomics has revolutionized biomedical research, which allows an unbiased global analysis of changes in DNA, RNA, proteins, and metabolites in disease settings, even at single-cell and spatial resolutions. They help us to identify critical regulators of inflammation processes and provide an overview of cell heterogeneity in DKD. This review aims to summarize the application of multiple omics in the field of DKD and emphasize the latest evidence on the interplay of inflammation and DKD revealed by these technologies, which will provide new insights into the role of inflammation in the pathogenesis of DKD and lead to the development of novel therapeutic approaches and diagnostic biomarkers

Prevalence, Predictors, and Outcomes of Pulmonary Hypertension in Patients with Lupus Nephritis

Background and Objectives: This study aimed to assess the prevalence, predictors, and outcomes of pulmonary hypertension (PH) in patients with lupus nephritis (LN). Materials and Methods: Baseline characteristics and clinical outcomes of 387 patients with LN were retrospectively collected from 2007 to 2017. PH was defined as pulmonary artery systolic pressure ≥40 mmHg assessed by resting transthoracic echocardiography. The primary endpoint was all-cause mortality. The secondary endpoint was renal events, defined as the doubling of baseline serum creatinine or end-stage renal disease. Associations between PH and outcomes were analyzed by Cox regression models. Results: A total of 15.3% (59/387) of patients with LN were diagnosed with PH, and the prevalence of PH was higher for patients with an estimated glomerular filtration rate (eGFR) 2 compared to those with an eGFR ≥ 30 mL/min/1.73 m2 (31.5% vs. 12.6%). Higher mean arterial pressure, lower hemoglobin, and lower triglyceride levels were associated with greater odds of having PH. After adjusting for relevant confounding variables, PH was independently associated with a higher risk for death (HR: 2.01; 95% CI: 1.01–4.00; p = 0.047) and renal events (HR: 2.07; 95% CI: 1.04–4.12; p = 0.039). Conclusions: PH is an independent risk factor for all-cause mortality and adverse renal outcomes in patients with LN

Metabolite Profiling of Feces and Serum in Hemodialysis Patients and the Effect of Medicinal Charcoal Tablets

Background/Aims: Recently, the colon has been recognized as an important source of various uremic toxins in patients with end stage renal disease. Medicinal charcoal tablets are an oral adsorbent that are widely used in patients with chronic kidney disease in China to remove creatinine and urea from the colon. A parallel fecal and serum metabolomics study was performed to determine comprehensive metabolic profiles of patients receiving hemodialysis (HD). The effects of medicinal charcoal tablets on the fecal and serum metabolomes of HD patients were also investigated. Methods: Ultra-performance liquid chromatography/mass spectrometry was used to investigate the fecal and serum metabolic profiles of 20 healthy controls and 31 HD patients before and after taking medicinal charcoal tablets for 3 months. Results: There were distinct metabolic variations between the HD patients and healthy controls both in the feces and serum according to multivariate data analysis. Metabolic disturbances of alanine, aspartate and glutamate metabolism, arginine and proline metabolism figured prominently in the serum. However, in the feces, alterations of tryptophan metabolism, lysine degradation and beta-alanine metabolism were pronounced, and the levels of several amino acids (leucine, phenylalanine, lysine, histidine, methionine, tyrosine, and tryptophan) were increased dramatically. Nineteen fecal metabolites and 21 serum metabolites were also identified as biomarkers that contributed to the metabolic differences. Additionally, medicinal charcoal treatment generally enabled the serum and fecal metabolomes of the HD patients to draw close to those of the control subjects, especially the serum metabolic profile. Conclusion: Parallel fecal and serum metabolomics uncovered the systematic metabolic variations of HD patients, especially disturbances in amino acid metabolism in the colon. Medicinal charcoal tablets had an impact on the serum and fecal metabolomes of HD patients, but their exact effects still need to be studied further

Global Transcriptomic Analyses Reveal Genes Involved in Conceptus Development During the Implantation Stages in Pigs

Prenatal mortality remains a significant concern to the pig farming industry around the world. Spontaneous fetal loss ranging from 20 to 45% by term occur after fertilization, with most of the loss happening during the implantation period. Since the factors regulating the high mortality rates of early conceptus during implantation phases are poorly understood, we sought to analyze the overall gene expression changes during this period, and identify the molecular mechanisms involved in conceptus development. This work employed Illumina’s next-generation sequencing (RNA-Seq) and quantitative real-time PCR to analyze differentially expressed genes (DEGs). Soft clustering was subsequently used for the cluster analysis of gene expression. We identified 8236 DEGs in porcine conceptus at day 9, 12, and 15 of pregnancy. Annotation analysis of these genes revealed rRNA processing (GO:0006364), cell adhesion (GO:1904874), and heart development (GO:0007507), as the most significantly enriched biological processes at day 9, 12, and 15 of pregnancy, respectively. In addition, we found various genes, such as T-complex 1, RuvB-like AAA ATPase 2, connective tissue growth factor, integrins, interferon gamma, SLA-1, chemokine ligand 9, PAG-2, transforming growth factor beta receptor 1, and Annexin A2, that play essential roles in conceptus morphological development and implantation in pigs. Furthermore, we investigated the function of PAG-2 in vitro and found that PAG-2 can inhibit trophoblast cell proliferation and migration. Our analysis provides a valuable resource for understanding the mechanisms of conceptus development and implantation in pigs

Resveratrol delays polycystic kidney disease progression through attenuation of nuclear factor κB-induced inflammation

BACKGROUND: Inflammation plays an important role in polycystic kidney disease (PKD). The current study aimed to examine the efficacy of the anti-inflammatory compound resveratrol in PKD and to investigate its underlying mechanism of action. METHODS: Male Han:SPRD (Cy/+) rats with PKD were treated with 200 mg/kg/day resveratrol or vehicle by gavage for 5 weeks. Human autosomal dominant (AD) PKD cells, three-dimensional (3D) Madin-Darby canine kidney cells and zebrafish were treated with various concentrations of resveratrol or the nuclear factor κB (NF-κB) inhibitor QNZ. RESULTS: Resveratrol treatment reduced blood urea nitrogen levels and creatinine levels by 20 and 24%, respectively, and decreased two-kidney/total body weight ratio by 15% and cyst volume density by 24% in Cy/+ rats. The proliferation index and the macrophage infiltration index were reduced by 40 and 43%, respectively, in resveratrol-treated cystic kidneys. Resveratrol reduced the levels of the pro-inflammatory factors monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α) and complement factor B (CFB) in Cy/+ rat kidneys in parallel with the decreased activity of NF-κB (p50/p65). The activation of NF-κB and its correlation with pro-inflammatory factor expression were confirmed in human ADPKD cells and kidney tissues. Resveratrol and QNZ inhibited the expression of MCP-1, TNF-α and CFB and reduced NF-κB activity in ADPKD cells. Moreover, NF-κB blockage minimized the inhibition of inflammatory factor production by resveratrol treatment. Furthermore, resveratrol or QNZ inhibited cyst formation in the 3D cyst and zebrafish models. CONCLUSIONS: The NF-κB signaling pathway is activated and partly responsible for inflammation in polycystic kidney tissues. Targeting inflammation through resveratrol could be a new strategy for PKD treatment in the future