Expression of VEGF-A Signaling Pathway in Cartilage of ACLT-induced Osteoarthritis Mouse Model.

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.

The activation and function of IL-36γ in neutrophilic inflammation in chronic rhinosinusitis.

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-1ß, 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.

Transcriptome analysis reveals manifold mechanisms of cyst development in ADPKD.

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.

A telomerase immortalized human proximal tubule cell line with a truncation mutation (Q4004X) in polycystin-1.

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. 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.

Ectopic expression of cadherin 8 is sufficient to cause cyst formation in a novel 3D collagen matrix renal tubule culture.

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.

[The iodine status in Hangzhou, Zhejiang province 2010].

OBJECTIVE: To explore the iodine level in the environment and the iodine status among the general population as well as the prevalence of thyroid nodules in Hangzhou city. Relationship between the prevalence of thyroid nodules and the policy of universal salt iodization in Hangzhou was also analyzed. METHODS: Questionnaire, a 3-day weighed dietary record method, and 3 days' 24-hour dietary recall method were used to understand the iodine nutrition status and dietary intake of iodine among the general population in the city. Drinking water, edible salt and morning urine were collected to determine iodine content. All objects under survey underwent the thyroid B ultrasonic examination. Statistical analysis was done by SPSS 13.0 and SAS 9.1. RESULTS: (1) In total, 12 620 effective questionnaires were available, with 221 water samples, 12 730 urine samples, and 3593 salt samples collected. 12 515 objects underwent B ultrasonic examination, and 1848 received dietary investigation. (2) Water iodine level of Hangzhou was in the range of 0.20 - 5.99 µg/L, with the median level as 2.58 µg/L. (3) Average daily dietary intake of iodine for adult males in Hangzhou was 289.2 µg/d. The contribution of iodine intake from iodized salt was 74.4%. (4) The median of Hangzhou residents' urinary iodine was 178.80 µg/L, with the urinary iodine levels at 100 µg/L-, 200 µg/L-, < 100 µg/L, and ≥ 300 µg/L groups were 37.14%, 23.11%, 21.05%, and 18.69% respectively. Urinary iodine of pregnant women was 141.0 µg/L. (5) Incidence of thyroid nodules in females (28.6%) was higher than that of males (20.1%). The detection rate increased with age (6.4% at group 6-, 10.9% at 12-, 12.0% at 18-, 24.4% at 40-, and 38.8% at 65-); with the highest in urban area (29.8%), followed by suburbs (23.3%) and in rural area it showed the least (20.3%). Urinary iodine level was found lower among the population who had been detected with thyroid nodules (160.36 µg/L) than those among the undetected population (182.00 µg/L). CONCLUSION: Hangzhou appeared to be an area where the environmental was iodine deficient. Iodized salt was the major source of iodine intake. The iodine status among the general population seemed to be safe and suitable, but the iodine level for pregnant women was not sufficient. There was still no evidence indicating that the universal salt iodization policy in Hangzhou was associated with the prevalence of thyroid nodules.

[Combination effects of enhanced UV-B radiation and O3 stress on photosynthetic characteristics of winter wheat].

Experiments were conducted under open-top-chambers conditions to assess the photosynthetic responses of wheat plants (Triticum aestivum L., YangMail6) to supplemental UV-B radiation (10%-10.9% higher then control group, T1) and enhanced ozone [(100 +/- 9) nmol x mol(-1), T2], separately and in combination (combination treatment, T3), making use of LCpro + Portable Photosynthesis System and DIVING-PAM Fluorometer to determine gas exchange and chlorophyll fluorescence parameters. Results indicated that P(n), G(s), T(r), P(m) and I(k) of T1, T2 and T3 treatments decreased significantly compared to CK (control group, natural air and UV-B radiant intensity condition), while there were no differences between T3 and T1 or T2 or both in major growth stages. UV-B fiercely inhibited the stomatal conductance and transpiration of plants, while T1 stimulated stomata opening and transpiration in jointing stage. Dark respiration (R(d)) of T1 was increased, while no significance difference was found between T2 and CK or T3 and CK in most stages. T1 and T2 reduced F(v)/F(m) value only in booting stage, while T3 was significant lower than CK except jointing stage. qP value declined significantly in treatments of T1, T2 and T3 as Compared to CK, with decreasing amplitude occurring in the order T3 > T1 > T2. NPQ, Y (NPQ), Y (NO) value of T1, T2 and T3 treatments increased significantly compared to CK, with maximum increasing amplitude occurring in the order T3 > T1 > T2, of which NPQ of T1 and T2 turned to decrease since filling stage, and T3 turned to decrease since flowering stage to a greater degree than T1 and T2. T1, T2 and T3 also caused significance reduction in Y (II), with reducing amplitude occurring in the order T3 > T1 > T2. Obviously, supplemental UV-B radiation and enhanced ozone caused a significant decrease in gas exchange capacity, maximum photochemical capacity and photosynthetic activity of winter wheat, and the photoprotective mechanism was damage, leading to greater proportion of excitation energy dissipated in the form of non-regulated heat and fluorescence. The photosystems of winter wheat were damaged by both excess energy and UV-B or excess energy and O3, or excess energy, UV-B and O3 together. UV-B and O3 in combination enhanced the negative effects on photo-protective mechanisms and excitation energy distribution in PS II compared to UV-B or O3 alone, while the interactive effects were less than addition.