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Background Anterior cruciate ligament transection surgery (ACLT)-induced OA model was often used to investigate the molecular mechanism of knee osteoarthritis (KOA). Researches have shown that vascular endothelial growth factor (VEGF) played an important role in OA. The present study aimed to investigate the pathological changes after ACLT surgery and reveal the expression characteristics of the VEGF-A/VEGFR2 signaling pathway in this model. Methods Moderate KOA model was established by ACLT, and 1, 2, 4, 8, and 12 weeks after surgery, hematoxylin-eosin (HE) and Safranin-O(S-O) staining were used to detect the pathological changes in mouse knee cartilage, and the matrix biomarkers A Disintegrin and Metalloproteinase with Thrombospondin Motifs 5(ADAMTS5), Collagen II (COL-II) were detected using immunohistochemistry (IHC), CD31 was detected by immunofluorescence (IF) to show the vascular invasion in cartilage, and proteins expression of VEGF-A pathway were detected by Western blot (WB). Meanwhile, the inflammatory biomarkers cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in cartilage were detected by WB. Results ACLT surgery can lead to degeneration of cartilage in mice, and the characteristics of the lesion were time-dependent. The ADAMTS5-positive cells increased while COL-II decreased in OA cartilage with time, and new blood vessels labeled by CD31 can be seen from 1 week in OA cartilage, and increased in 8 and 12 weeks. The expression of VEGF-A, VEGFR2, COX-2, and iNOS were higher than control groups, which were basically consistent with the degree of osteoarthritis. Conclusions The degenerative degree of articular cartilage was time-dependent; angiogenesis and inflammation were important pathological changes of cartilage in KOA. The expression of the VEGF-A/VEGFR2 signaling pathway was basically correlated with the degree of KOA.

Despite substantial progress in identifying and understanding causative mutations in autosomal dominant polycystic kidney disease (ADPKD), little is known about subsequent cellular events leading to cyst formation. In prior studies we reported that Cadherin 8, a type II Cadherin, expression is sufficient to induce cyst emergence from HK-2 cells grown as tubule arrays in collagen matrix (1). However, emergent cysts did not exhibit the luminal enlargement observed in ADPKD. In this communication, we reconstitute cyst emergence with consequent cyst lumen expansion in 3D culture by stable co-expression of Cadherin 8 in combination with a constitutively active mutant of YAP1, the key effector of the HIPPO pathway. Specifically, immortalized cells derived from ADPKD cyst epithelia formed cysts with substantially larger lumen sizes when transduced with YAP1-5SA. Conversely, expression of the YAP1 inhibitor, AMOTL1, in these cells resulted in their forming cysts with smaller lumens than control cells. Our data show that cyst formation results from a sequential two-step process consisting of cyst initiation and subsequent cyst expansion. Taken together, cyst initiation induced by Cadherin 8 expression is proposed to result from decreased cell-cell adhesion while cyst expansion is driven by increased Yap1 activity.

OBJECTIVE: To study the characteristics of gut microbiota and its association with the activity of β-glucuronidase (β-GD) in neonates with hyperbilirubinemia. METHODS: A total of 50 neonates with hyperbilirubinemia who were admitted in January to December, 2018, were enrolled as the hyperbilirubinemia group, and 30 neonates without hyperbilirubinemia were enrolled as the control group. The 16S rRNA high-throughput sequencing method was used to compare gut microbiota between the two groups. The phenolphthalein-glucuronic acid substrate method was used to measure the activity of β-GD in the intestinal tract of neonates with hyperbilirubinemia before and after treatment. RESULTS: The comparison of the distribution of gut microbiota at the genus level showed a significant difference in the abundance of 52 bacteria between the hyperbilirubinemia and control groups before treatment (P < 0.05), as well as a significant difference in the abundance of 42 bacteria between the hyperbilirubinemia group on day 3 after treatment and the control group on day 3 after enrollment (P < 0.05). After treatment, the hyperbilirubinemia group had significant reductions in the content of Escherichia and Staphylococcus in the intestinal tract (P < 0.05) and the activity of β-GD in feces (P < 0.05). The activity of β-GD in feces was positively correlated with the abundance of Staphylococcus and Escherichia before and after treatment in the neonates with hyperbilirubinemia (r(s)=0.5948-0.7245, P < 0.01). CONCLUSIONS: There are differences in gut microbiota between the neonates with hyperbilirubinemia and those without hyperbilirubinemia. The activity of β-GD in feces is positively correlated with the abundance of Staphylococcus and Escherichia in neonates with hyperbilirubinemia. Gut microbiota may affect the development of neonatal hyperbilirubinemia by regulating the activity of β-GD. The determination and analysis of gut microbiota and β-GD activity may have certain clinical significance for the early assessment of the development of neonatal hyperbilirubinemia.

OBJECTIVE: To study the effectiveness of Saccharomyces boulardii combined with phototherapy in the treatment of hyperbilirubinemia in neonates. METHODS: The neonates with hyperbilirubinemia who were hospitalized from January to December 2018 were enrolled and randomly divided into an observation group (n=61) and a control group (n=63). The neonates in the observation group were treated with phototherapy combined with Saccharomyces boulardii, and those in the control group were treated with phototherapy combined with placebo. Treatment outcomes were compared between the two groups. Fecal samples were collected 72 hours after treatment and 16s rRNA high-throughput sequencing was used to compare the features of gut microbiota between the two groups. RESULTS: There was no significant difference in the total serum bilirubin level between the two groups before treatment (P > 0.05). At 24, 48, and 72 hours after treatment, the observation group had a significantly lower level of total serum bilirubin than the control group (P < 0.05). Compared with the control group, the observation group had a significantly lower proportion of neonates requiring phototherapy again[20% (12/61) vs 75% (47/63), P < 0.05]. Compared with the control group, the observation group had a significantly higher abundance of Bacteroides (P < 0.05) and a significantly lower abundance of Escherichia coli and Staphylococcus in the intestine at 72 hours after treatment (P < 0.05). CONCLUSIONS: In neonates with hyperbilirubinemia, phototherapy combined with Saccharomyces boulardii can effectively reduce bilirubin level and prevent the recurrence of jaundice. Saccharomyces boulardii can favour the treatment outcome by regulating the gut microbiota of neonates.

Background Although increased accumulation of neutrophils has been noted in chronic rhinosinusitis (CRS), the function and regulation of neutrophils in CRS are largely unknown. IL-36 family cytokines may play an important role in neutrophilic inflammation. Objective This study sought to investigate the expression and function of IL-36 cytokines in CRS. Methods Quantitative RT-PCR, immunohistochemistry, immunofluorescence, and ELISA were used to investigate the expression of IL-36 cytokines and IL-36 receptor (IL-36R) in sinonasal mucosa. The expression of IL-36R on neutrophils in polyps and blood was measured by flow cytometry. Purified blood neutrophils were cultured to investigate the regulation of IL-36R expression. The cleavage of IL-36γ was detected by Western blotting. Dispersed nasal polyp cells were treated with IL-36γ with or without elastase inhibitor and dexamethasone. Results Neutrophil infiltration and expression of IL-36 cytokines and IL-36R were upregulated in both CRS with and without nasal polyps. IL-36γ was the most abundant isoform and mainly expressed by epithelial cells in CRS. Neutrophils were the principal IL-36R + cell type in polyps. IL-36R expression was almost absent in blood neutrophils and upregulated by IL-6, IL-1β, and Dermatophagoides pteronyssinus group 1. Elastase activity was increased in polyps and degraded full-length IL-36γ. Consistently, the levels of cleaved IL-36γ were increased in polyps. Full-length IL-36γ promoted the production of matrix metalloproteinase 9; IL-17A; and chemokine (C-X-C motif) ligands 1, 2, and 8 from dispersed nasal polyp cells, which was abolished by elastase inhibitor. The proinflammatory effect of IL-36γ was not suppressed by dexamethasone. Conclusions Increased production and activation of IL-36γ may act on neutrophils and further exaggerate neutrophilic inflammation in CRS.

Ischemic preconditioning confers organ-wide protection against subsequent ischemic stress. A substantial body of evidence underscores the importance of mitochondria adaptation as a critical component of cell protection from ischemia. To identify changes in mitochondria protein expression in response to ischemic preconditioning, we isolated mitochondria from ischemic preconditioned kidneys and sham-treated kidneys as a basis for comparison. The proteomic screen identified highly upregulated proteins, including NADP+-dependent isocitrate dehydrogenase 2 (IDH2), and we confirmed the ability of this protein to confer cellular protection from injury in murine S3 proximal tubule cells subjected to hypoxia. To further evaluate the role of IDH2 in cell protection, we performed detailed analysis of the effects of Idh2 gene delivery on kidney susceptibility to ischemia-reperfusion injury. Gene delivery of IDH2 before injury attenuated the injury-induced rise in serum creatinine (P

While a variety of genetic mutations have been shown to be associated with renal cyst formation, mechanisms of renal cyst formation are largely unknown. In prior communications we described alterations in E-cadherin assembly in cultured cystic epithelial cells (Charron AJ, Nakamura S, Bacallao R, Wandinger-Ness A. J Cell Biol 149: 111–124, 2000). Using the same cell line we assayed cadherin expression by RT-PCR using primer pairs that anneal to highly conserved sequences of cadherin genes but flank informative regions of cadherins. Using this approach we found that autosomal dominant polycystic kidney disease (ADPKD) cells express cadherin 8, a neuronal cadherin with limited expression in the kidney. Immunohistochemistry confirmed cadherin 8 expression in cystic epithelia. To test the functional significance of cadherin 8 expression in renal epithelial cells, we adapted a three-dimensional collagen culture method in which HK-2 cells form tubule structures and microinjected adenovirus into the matrix space surrounding tubule structures. Adenovirus expressing cadherin 8 under the control of a tet promoter caused cyst structures to grow out of the tubules when coinjected with adenovirus expressing a tet transactivator. Microinjection of single adenovirus expressing either tet transactivator or cadherin 8 failed to cause cyst formation. When doxycycline was added to the culture, following coinjection of adenovirus, there was a dose-response reduction in cadherin 8 expression and cyst formation. Similarly, HK-2 cells transfected with Flag-tagged cadherin 8 form cysts in addition to tubular structures. HK-2 cells transfected with Flag-tagged N-cadherin do not form cysts. These data suggest that ectopic expression of cadherin 8 in renal epithelial cells is sufficient to cause the morphogenic pattern of cyst formation.

Background Autosomal dominant polycystic kidney disease (ADPKD) causes progressive loss of renal function in adults as a consequence of the accumulation of cysts. ADPKD is the most common genetic cause of end-stage renal disease. Mutations in polycystin-1 occur in 87% of cases of ADPKD and mutations in polycystin-2 are found in 12% of ADPKD patients. The complexity of ADPKD has hampered efforts to identify the mechanisms underlying its pathogenesis. No current FDA (Federal Drug Administration)-approved therapies ameliorate ADPKD progression. Results We used the de Almeida laboratory’s sensitive new transcriptogram method for whole-genome gene expression data analysis to analyze microarray data from cell lines developed from cell isolates of normal kidney and of both non-cystic nephrons and cysts from the kidney of a patient with ADPKD. We compared results obtained using standard Ingenuity Volcano plot analysis, Gene Set Enrichment Analysis (GSEA) and transcriptogram analysis. Transcriptogram analysis confirmed the findings of Ingenuity, GSEA, and published analysis of ADPKD kidney data and also identified multiple new expression changes in KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways related to cell growth, cell death, genetic information processing, nucleotide metabolism, signal transduction, immune response, response to stimulus, cellular processes, ion homeostasis and transport and cofactors, vitamins, amino acids, energy, carbohydrates, drugs, lipids, and glycans. Transcriptogram analysis also provides significance metrics which allow us to prioritize further study of these pathways. Conclusions Transcriptogram analysis identifies novel pathways altered in ADPKD, providing new avenues to identify both ADPKD’s mechanisms of pathogenesis and pharmaceutical targets to ameliorate the progression of the disease. Electronic supplementary material The online version of this article (doi:10.1186/s40246-016-0095-x) contains supplementary material, which is available to authorized users.

Ischemic preconditioning is well known to afford protection against subsequent episodes of ischemia/reperfusion (I/R) in multiple organs, including the kidney, but the mechanisms involved are not fully understood. We proposed that ischemic preconditioning results in an altered mitochondrial proteome that confers resistance to subsequent I/R injury. We subjected rats to moderate ischemic injury and used liquid chromatography – mass spectroscopy (LC/MS) to analyze the proteome of kidney cortical mitochondria isolated following 14 days of recovery from I/R. The expression of several proteins was elevated following preconditioning, and two were selected for further analysis: Isocitrate dehydrogenase 2 (IDH2) and a member of the sulfotransferase family (SULT1A1). The effect of increased expression of these proteins was evaluated by using hydrodynamic gene delivery of plasmid vectors to overexpress each protein. Strikingly, hydrodynamic delivery of IDH2 and SULT1A1 genes attenuated the peak in serum creatinine ...

The microvascular wall is remarkably simple, consisting only of the endothelial lining, subjacent basal lamina, and underlying periendothelial cells. This study describes the characterization of a novel microvascular protein. This 80,000-molecular weight protein was predominantly associated with electron-lucent amorphous material in capillary basal laminae and therefore termed cablin (protein of the capillary basal lamina). Consistent with its immunolocalization to the microvasculature, cablin was synthesized and secreted by cultured endothelial cells and vascular smooth muscle cells. Furthermore, cablin expression was induced during neovascularization. The predicted amino acid sequence of cablin revealed a prevalence of polar amino acids. Accounting for the low yet significant homology to several α-helical proteins, these residues were best accommodated by secondary structure predictions that aligned the molecule into two large α-helical domains. The presence of the integrin-binding RGD tripeptide and a putative elastin-binding sequence suggest that this rodlike molecule is suited to cross-link cells and matrix constituents. In this capacity it could contribute to the mechanical strength or the angiogenic potential of the microvasculature.

Batten disease, the juvenile form of neuronal ceroid lipofuscinosis, is a prevalent neuron degenerative disorder of childhood. A 1.02-kb genomic deletion in the Batten disease gene CLN3 has been determined to be a common mutation. We developed a PCR method to screen for this deletion and tested 43 Batten disease probands. We found 36% (31/86) of Batten disease chromosomes did not carry the 1.02-kb deletion. Of the three heterozygotes for the 1.02-kb deletion, a novel G-to-A missense mutation at nucleotide 1020 of the CLN3 cDNA sequence was found on two of the non-1.02-kb deletion chromosomes. The missense mutation resulted in a substitution of glutamic acid (E) by lysine (K) at position 295 (E295 K). The E295 K mutation causes a change in predicted local protein conformation. This glutamic acid is a highly conserved acidic amino acid, being present in human, mouse, dog and yeast, which suggests it may play an important role in the function of the Batten disease protein.

Autosomal dominant polycystic kidney disease (ADPKD) is associated with a variety of cellular phenotypes in renal epithelial cells. Cystic epithelia are secretory as opposed to absorptive, have higher proliferation rates in cell culture and have some characteristics of epithelial to mesenchymal transitions [1], [2]. In this communication we describe a telomerase immortalized cell line that expresses proximal tubule markers and is derived from renal cysts of an ADPKD kidney. These cells have a single detectable truncating mutation (Q4004X) in polycystin-1. These cells make normal appearing but shorter cilia and fail to assemble polycystin-1 in the cilia, and less uncleaved polycystin-1 in membrane fractions. This cell line has been maintained in continuous passage for over 35 passages without going into senescence. Nephron segment specific markers suggest a proximal tubule origin for these cells and the cell line will be useful to study mechanistic details of cyst formation in proximal tubule cells.