IL-6 Reduces Spheroid Sizes of Osteophytic Cells Derived from Osteoarthritis Knee Joint via Induction of Apoptosis.

Osteophytes in osteoarthritis (OA) joints contribute to restriction of joint movement, joint pain, and OA progression, but little is known about osteophyte regulators. Examination of gene expression related to cartilage extracellular matrix, endochondral ossification, and growth factor signaling in articular cartilage and osteophytes obtained from OA knee joints showed that several genes such as COL1A1, VCAN, BGLAP, BMP8B, RUNX2, and SOST were overexpressed in osteophytes compared with articular cartilage. Ratios of mesenchymal stem/progenitor cells, which were characterized by co-expression of CD105 and CD166, were significantly higher in osteophytic cells than articular cells. A three-dimensional culture method for cartilage and osteophyte cells was developed by modification of cultures of self-assembled spheroid cell organoids (spheroids). These spheroids cultured in the media for mesenchymal stem cells containing transforming growth factor-ß3 showed characteristic morphologies and gene expression profiles of articular cartilage and osteophytes, respectively. The effects of IL-1ß, tumor necrosis factor-α, and IL-6 on the spheroids of articular and osteophytic cells were studied. To the best of our knowledge, they provide the first evidence that IL-6 suppresses the spheroid size of osteophytic cells by inducing apoptosis and reducing extracellular matrix molecules. These data show that IL-6 is the suppressor of osteophyte growth and suggest that IL-6 expression and/or activity are implicated in the regulation of osteophyte formation in pathologic joints.

Medial meniscus extrusion is invariably observed and consistent with tibial osteophyte width in elderly populations: The Bunkyo Health Study.

We reported that the full-length width of medial tibial osteophytes comprising cartilage and bone parts correlates with medial meniscus extrusion (MME) in early-stage knee osteoarthritis (OA). However, no data exist on the prevalence of MME and its relationship with osteophytes in the elderly population. 1191 elderly individuals (females 57%; 72.9 years old on average) in the Bunkyo Health Study underwent standing plain radiograph and proton density-weighted MRI on knee joints. MRI-detected OA changes were evaluated according to the Whole-Organ Magnetic Resonance Imaging Score. A new method of assessing the cartilage and bone parts of osteophytes was developed using pseudo-coloring images of proton density-weighted fat-suppressed MRI. Most subjects showed Kellgren-Lawrence grade 1 or 2 radiographic medial knee OA (88.1%), MME (98.7%, 3.90 ± 2.01 mm), and medial tibial osteophytes (99.3%, 3.27 ± 1.50 mm). Regarding OA changes, MME was closely associated with the full-length width of medial tibial osteophytes (ß = 1.114; 95% CI 1.069-1.159; p < 0.001) in line with osteophyte width (intraclass correlation coefficient, 0.804; 95% CI 0.783-0.823). Our data revealed that MME and medial tibial osteophytes are observed in the elderly and demonstrate that the degree of MME is consistent with the full-length width of medial tibial osteophytes, suggesting that osteophytes might be implicated in MME.

Anterior meniscus extrusion is associated with anterior tibial osteophyte width in knee osteoarthritis - The Bunkyo Health Study.

Background: In knee osteoarthritis (OA), medial meniscus extrudes both medially and anteriorly. We reported that full-length width of medial tibial osteophyte, which comprises cartilage and bone parts, is directly associated with medial meniscus extrusion in early-stage knee OA and hypothesized that anterior tibial osteophyte (ATO) is also associated with anterior meniscus extrusion (AME). Thus, we aimed to examine their prevalence and relationship. Methods: Elderly subjects (638 females and 507 males; average 72.9 years old) in the Bunkyo Health Study cohort were enrolled. MRI-detected OA changes were evaluated according to the Whole Organ Magnetic Resonance Imaging Score. ATO was evaluated using the method which can assess both cartilage and bone parts of osteophyte by pseudo-coloring images of proton density-weighted fat-suppressed MRI. Results: Most subjects showed the Kellgren-Lawrence grade 1/2 of the medial knee OA (88.1%), AME (94.3%, 3.7 â€‹± â€‹2.2 â€‹mm), and ATO (99.6%, 4.2 â€‹± â€‹1.5 â€‹mm). Among the OA changes, AME was most closely associated with full-length width of ATO (multivariable ߠ​= â€‹0.877, p â€‹< â€‹0.001). The area under the receiver operating characteristic curve for determining the presence of AME as evaluated by ATO width was 0.75 (95% confidence interval 0.60-0.84, p â€‹< â€‹0.001). The odds ratio for the presence of AME as evaluated by ATO width at 2.9 â€‹mm was 7.16 (4.23-12.15, p â€‹< â€‹0.001, age, gender, BMI, and K-L adjusted). Conclusions: AME and ATO were inevitably observed in the elderly subjects and AME was closely associated with full-length width of ATO. Our study provides the first evidence on the close relationship between AME and ATO in knee OA.

Periostin derived from cancer-associated fibroblasts promotes esophageal squamous cell carcinoma progression via ADAM17 activation.

Periostin (POSTN) is a matricellular protein that was originally identified in osteoblasts. Past studies have shown that POSTN is also preferentially expressed in cancer-associated fibroblasts (CAFs) in various types of cancer. We previously demonstrated that the increased expression of POSTN in stromal tissues is associated with an unfavorable clinical outcome in esophageal squamous cell carcinoma (ESCC) patients. In this study, we aimed to elucidate the role of POSNT in ESCC progression and its underlying molecular mechanism. We found that POSTN is predominantly produced by CAFs in ESCC tissues, and that CAFs-cultured media significantly promoted the migration, invasion, proliferation, and colony formation of ESCC cell lines in a POSTN-dependent manner. In ESCC cells, POSTN increased the phosphorylation of ERK1/2 and stimulated the expression and activity of a disintegrin and metalloproteinase 17 (ADAM17), which is critically involved in tumorigenesis and tumor progression. The effects of POSTN on ESCC cells were suppressed by interfering with the binding of POSTN to integrin αvß3 or αvß5 using neutralizing antibody against POSTN. Taken together, our data show that CAFs-derived POSTN stimulates ADAM17 activity through activation of the integrin αvß3 or αvß5-ERK1/2 pathway and thereby contributes to the progression of ESCC.

Medial meniscus extrusion is directly correlated with medial tibial osteophyte in patients received reconstruction surgery for anterior cruciate ligament injury: A longitudinal study.

Objective: Anterior cruciate ligament (ACL) injury is one of the causes for post-traumatic knee osteoarthritis (OA), and ACL reconstruction surgery is reportedly unable to prevent OA development. In early-stage knee OA, medial meniscus extrusion (MME) is closely correlated with tibial medial osteophyte width, which consists of bone and cartilage -parts. However, the relationship between MME and osteophyte in ACL-injured patients remains elusive. We examined MME and osteophyte and their relationship in ACL-injured patients before and after surgery. Design: Thirty ACL-injured patients who underwent surgery (30.7 years old, on average) were enrolled. Correlations between magnetic resonance imaging (MRI)-detected OA changes and MME before and after surgery (7.6 months interval) were analyzed. Results: MME (>3 â€‹mm) was present in 16.7% and 26.7% of the patients before and after surgery, respectively, and MME was significantly increased after surgery (2.4 â€‹± â€‹1.3 â€‹mm) than before surgery (1.9 â€‹± â€‹1.2 â€‹mm) (p â€‹< â€‹0.0001). Full-length tibial osteophyte width measured by T2 mapping MRI was significantly increased after surgery (1.9 â€‹± â€‹0.7 â€‹mm) than before surgery (1.4 â€‹± â€‹0.6 â€‹mm) (p â€‹< â€‹0.0001). Among OA structural changes, only medial tibial osteophyte width directly correlated with MME before surgery (ߠ​= â€‹0.962) (p â€‹< â€‹0.001) and after surgery (ߠ​= â€‹0.928) (p â€‹= â€‹0.001). All the patients with MME had medial tibial osteophyte before and after surgery. A direct correlation was observed between changes of MME and those of medial tibial osteophyte width before and after surgery (r â€‹= â€‹0.63) (p â€‹< â€‹0.0001). Conclusion: MME and medial tibial osteophyte were simultaneously increased after surgery. In addition to close correlation between MME and medial tibial osteophyte width, changes of MME and medial tibial osteophyte width before and after surgery were directly correlated.

Expression and regulation of recently discovered hyaluronidases, HYBID and TMEM2, in chondrocytes from knee osteoarthritic cartilage.

Destruction of articular cartilage in osteoarthritis (OA) is initiated by depletion of the hyaluronan (HA)-aggrecan network, followed by degradation of the collagen fibrils. Previously, we reported the implications of HA-binding protein involved in HA depolymerization (HYBID), alias cell migration-inducing protein (CEMIP) and KIAA1199, for HA degradation. However, transmembrane protein 2 (TMEM2), which is ~ 50% homologous to HYBID, was discovered as another hyaluronidase, but their expression and regulation by OA chondrocytes remain elusive. Here we report that the absolute mRNA copy numbers of HYBID are significantly (7.1-fold) higher in OA cartilage than normal cartilage, whereas TMEM2 levels are not different between the groups. HA-degrading activity of cultured OA chondrocytes disappeared by siRNA-mediated knockdown of HYBID, but not TMEM2. HYBID expression was significantly up-regulated by treatment with interleukin-6 (IL-6) or tumor necrosis factor-α (TNF-α) and additively increased by the combined treatment. No significant changes in the TMEM2 expression were seen by the factors examined. IL-1α remarkably enhanced IL-6 production and increased HYBID expression when soluble IL-6 receptor was supplemented. These results demonstrate that in stark contrast to the constitutive expression of TMEM2 and its negligible HA-degrading activity, HYBID is overexpressed in OA cartilage and up-regulated by IL-6 and TNF-α in OA chondrocytes.

Cancer-associated fibroblasts at the unfavorable desmoplastic stroma promote colorectal cancer aggressiveness: Potential role of ADAM9.

The tumor microenvironment plays a key role in cancer aggressiveness. Desmoplastic reaction (DR), morphologically classified as Mature, Intermediate and Immature types, has previously been shown to be highly prognostic in colorectal cancer (CRC) and it consists to a large extent of cancer-associated fibroblasts (CAFs). The aim of our study was to characterize the molecular background of DR and understand the effects of CAFs in tumor aggressiveness. The prognostic significance of DR was initially examined in 1497 patients. Then CAFs originating from patient tissues with different DR types were isolated and their impact on tumor growth was examined both in vitro and in vivo. DR was shown to be highly prognostic, with patients within the Immature DR group conferring the worst relapse-free survival. The conditioned media of CAFs from tumor with Immature-type DR (CAFsImmature ) significantly increased proliferation and migration of CRC cell lines and growth of CRC-derived organoids compared to that of CAFs from Mature-type DR (CAFsMature ). Subcutaneous or orthotopic implantation of CRC cells together with CAFsImmature in mice significantly promoted tumor growth and dissemination compared to implantation with CAFsMature . Systematic examination of the expression of "a disintegrin and metalloproteinases" (ADAMs) in CAFs isolated from CRC tissues showed that the secreted isoform of ADAM9 (ADAM9s) was significantly higher in CAFsImmature than in CAFsMature . Knockdown of ADAM9s in CAFsImmature abrogated the promoting effects on CRC cell proliferation and migration. CAFs-derived ADAM9s is implicated in deteriorating survival in CRC patients with Immature-type DR by increasing tumor cell proliferation and dissemination.

Synergistic upregulation of ADAMTS4 (aggrecanase-1) by cytokines and its suppression in knee osteoarthritic synovial fibroblasts.

The ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family includes nine members with aggrecan-degrading activity, i.e., ADAMTS1, 4, 5, 8, 9, 15, 16, 18, and 20. However, their systematic expression profile in knee osteoarthritis (OA) synovium and effects of cytokines and growth factors on the expression in OA synovial fibroblasts remain elusive. In this study, expression of all nine aggrecanolytic ADAMTS species was assessed by quantitative real-time PCR in OA and control normal synovial tissues. OA synovial fibroblasts were treated with interleukin-1α (IL-1α), IL-1ß, tumor necrosis factor-α (TNF-α), transforming growth factor-ß (TGF-ß), vascular endothelial growth factor165, and heparin-binding epidermal growth factor, and analyzed for the expression of the ADAMTS species. The signaling pathways and inhibition of ADAMTS4 expression by high-molecular-weight hyaluronan, adalimumab, tocilizumab, and signaling molecule inhibitors were studied. ADAMTS1, 4, 5, 9, and 16 were expressed in OA synovium, but only ADAMTS4 expression was significantly higher in OA as compared to normal synovium. IL-1α, TNF-α, and TGF-ß markedly increased ADAMTS4 expression, while their effects were minimal for the other ADAMTS species. ADAMTS4 was synergistically upregulated by treatment with IL-1α and TNF-α, IL-1α and TGF-ß, or IL-1α, TNF-α and TGF-ß. The signaling molecules' inhibitors demonstrated that IL-1α-induced ADAMTS4 expression is predominantly through TGF-ß-associated kinase 1 (TAK1), and the TNF-α-stimulated expression is via TAK1 and nuclear factor-κB (NF-κB). The TGF-ß-promoted expression was through the activin receptor-like kinase 5 (ALK5)/Smad2/3, TAK1, and non-TAK1 pathways. Adalimumab blocked TNF-α-stimulated expression. ADAMTS4 expression co-stimulated with IL-1α, TNF-α and TGF-ß was abolished by treatment with adalimumab, TAK1 inhibitor, and ALK5/Smad2/3 inhibitor. These data demonstrate marked and synergistic upregulation of ADAMTS4 by IL-1α, TNF-α and TGF-ß in OA synovial fibroblasts, and suggest that concurrent therapy with an anti-TNF-α drug and inhibitor(s) may be useful for prevention against aggrecan degradation in OA.

Deletion of Hyaluronan-Binding Protein Involved in Hyaluronan Depolymerization (HYBID) Results in Attenuation of Osteoarthritis in Mice.

Hyaluronan (HA)-binding protein involved in HA depolymerization (HYBID) is involved in cartilage destruction via HA depolymerization in human knee osteoarthritis. However, the role of HYBID in the progression of osteoarthritis remain elusive. This study sought to examine whether genetic depletion of Hybid could suppress surgically induced osteoarthritis of mouse knee joints. In osteoarthritis induced by medial collateral ligament transection with meniscus removal, articular cartilage destruction and osteophyte formation at the medial femoral-tibial joint were significantly inhibited in Hybid-deficient (Hybid-/-) mice compared with wild-type mice. Hybid was highly produced by synovial cells and articular chondrocytes in the osteoarthritis joints of wild-type mice. IL-1ß, IL-6, and tumor necrosis factor-α were up-regulated in the osteoarthritis joint tissues of both wild-type and Hybid-/- mice. Vascular density at the synovial and periosteal junction was significantly reduced in Hybid-/- mice compared with wild-type mice. High-molecular-weight HA accumulated in osteoarthritis joint tissues of Hybid-/- mice. Injections of high-molecular-weight HA to knee joints attenuated the cartilage destruction and osteophyte formation in wild-type mouse osteoarthritis group. Inhibition of cartilage destruction and osteophyte formation in Hybid-/- mice was also observed in destabilization of the medial meniscus model. These data are the first to demonstrate that cartilage destruction and osteophyte formation are suppressed in Hybid-/- mice and suggest that Hybid-mediated HA depolymerization is implicated for the progression of mechanically-induced knee osteoarthritis.

HYBID derived from tumor cells and tumor-associated macrophages contribute to the glioblastoma growth.

Glioblastoma is the most malignant tumor of the brain associated with poor prognosis and outcome, and hence there is an urgent need to develop novel treatments for glioblastoma. In this study, we focused on hyaluronan binding protein (HYBID, as known as CEMIP/KIAA1199), a protein involved in hyaluronan depolymerization in chondrocytes and synoviocytes. We previously reported that Hybid-deficient (KO) mice show accumulation of hyaluronan in the brain, and memory impairment. To elucidate the role of HYBID in glioblastoma pathogenesis, we knocked down HYBID in human glioblastoma cells using siRNAs and developed a murine orthotopic xenograft model in the Hybid KO mice. Downregulation of HYBID in glioblastoma cells resulted in inhibition of cell proliferation and migration, and increased cell death. The growth of glioblastoma cells implanted in the mouse brain was suppressed in Hybid KO mice compared to that in the wild-type mice. Interestingly, infiltration of macrophages in the glioblastoma tissue was decreased in Hybid KO mice. Using intraperitoneal macrophages derived from Hybid KO mice and glioma cell supernatants, we examined the role of HYBID in macrophages in the tumor environment. We showed that HYBID contributes to macrophage migration and the release of pro-tumor factors. Moreover, we revealed that HYBID can be a poor prognostic factor in glioma patients by bioinformatics approaches. Our study provides data to support that HYBID expressed by both glioblastoma cells and tumor-associated macrophages may contribute to glioblastoma progression and suggests that HYBID may be a potential target for therapy that focuses on the tumor microenvironment of glioblastoma.

An antibacterial coated polymer prevents biofilm formation and implant-associated infection.

To prevent infections associated with medical implants, various antimicrobial silver-coated implant materials have been developed. However, these materials do not always provide consistent antibacterial effects in vivo despite having dramatic antibacterial effects in vitro, probably because the antibacterial effects involve silver-ion-mediated reactive oxygen species generation. Additionally, the silver application process often requires extremely high temperatures, which damage non-metal implant materials. We recently developed a bacteria-resistant coating consisting of hydroxyapatite film on which ionic silver is immobilized via inositol hexaphosphate chelation, using a series of immersion and drying steps performed at low heat. Here we applied this coating to a polymer, polyetheretherketone (PEEK), and analyzed the properties and antibacterial activity of the coated polymer in vitro and in vivo. The ionic silver coating demonstrated significant bactericidal activity and prevented bacterial biofilm formation in vitro. Bio-imaging of a soft tissue infection mouse model in which a silver-coated PEEK plate was implanted revealed a dramatic absence of bacterial signals 10 days after inoculation. These animals also showed a strong reduction in histological features of infection, compared to the control animals. This innovative coating can be applied to complex structures for clinical use, and could prevent infections associated with a variety of plastic implants.

ß-Selective Glycosylation Using Axial-Rich and 2-O-Rhamnosylated Glucosyl Donors Controlled by the Protecting Pattern of the Second Sugar.

Herein, we describe two counterexamples of the previously reported ß/α-selectivity of 96/4 for glycosylation using ethyl 2-O-[2,3,4-tris-O-tert-butyldimethylsilyl (TBS)-α-L-rhamnopyranosyl]-3,4,6-tris-O-TBS-thio-ß-D-glucopyranoside as the glycosyl donor. Furthermore, we investigated the effects of protecting group on the rhamnose moieties in the glycosylation with cholestanol and revealed that ß-selectivity originated from the two TBS groups at the 3-O and 4-O positions of rhamnose. In contrast, the TBS group at the 2-O position of rhamnose hampered the ß-selectivity. Finally, the ß/α-selectivity during the glycosylation was enhanced to ≥99/1. The results obtained herein suggest that the protecting groups on the sugar connected to the 2-O of a glycosyl donor with axial-rich conformation can control the stereoselectivity of glycosylation.

Medial meniscus extrusion is a determinant factor for the gait speed among MRI-detected structural alterations of knee osteoarthritis.

Objective: Knee osteoarthritis (OA) is one of the most common causes for reduction in gait speed. Research into the mechanism of underlying knee OA pain and other symptoms such as the reduction in the gait speed is essential to development of disease-modifying treatments for knee OA. We examined the magnetic resonance imaging (MRI)-detected structural alterations in knee joints those were associated with gait speed in knee OA patients. Design: In this cross-sectional study, structural alterations in knee joints of 74 knee OA patients (51 females; mean 72.2 years old) were evaluated by MRI, and subjects' gait speed was measured. Results: The mean self-selected gait speed of the subjects was 0.73 â€‹± â€‹0.21 â€‹m/s. A simple linear regression analysis revealed that MME was only correlated with the gait speed of the subjects with knee OA, while cartilage lesion, bone marrow lesion, subchondral bone cyst, subchondral cyst, osteophytes and meniscal pathology were not. A multiple regression analysis revealed that only MME was associated with gait speed (R2 â€‹= â€‹0.484, p â€‹< â€‹0.001). The area under the receiver operating characteristic curve for determining <0.8 â€‹m/s of gait speed as evaluated by MME were 0.72 (95% confidence interval: 0.60-0.84). The relative risks at a cut-off <0.8 â€‹m/s for gait speed as evaluated by MME at 6.2 â€‹mm were 2.19 (1.28-3.46, p â€‹= â€‹0.01). Conclusions: MME was associated with and the determinant for gait speed among MRI-detected structural alterations in patients with knee OA, suggesting the importance for elucidating the etiology of MME for developing a disease-modifying treatment for knee OA.

Stromal metalloproteinases: Crucial contributors to the tumor microenvironment.

Proteolytic balance is crucial for the maintenance of tissue homeostasis. In cancer, dysregulated proteolysis is involved in unregulated tissue remodeling and inflammation, leading to the promotion of tumor growth, local invasion, and metastasis. Metalloproteinases, which were first identified as collagen cleaving enzymes, have been shown to extensively degrade extracellular matrix proteins or selectively release cell surface-bound cytokines, growth factors, or their receptors, thereby impacting extracellular matrix integrity, immune cell recruitment and tissue turnover. Although tumor cells produce various metalloproteinases, the major source is thought to be stromal cells infiltrating the tumor. Different types of stromal cells express specific sets of metalloproteinases and their inhibitors, which specifically alter the milieu within the tumor. In this review, recent findings and knowledge regarding metalloproteinases derived from stromal cells during the creation of the tumor microenvironment are described and their contribution to the tumor progression and metastasis discussed.

Significance of tumor microenvironment in acquiring resistance to vascular endothelial growth factor-tyrosine kinase inhibitor and recent advance of systemic treatment of clear cell renal cell carcinoma.

The development of systemic therapies, including vascular endothelial growth factor-tyrosine kinase inhibitors (VEGF-TKI) and mammalian target of rapamycin (mTOR) inhibitors, represents a major breakthrough in the treatment of patients with renal cell carcinoma (RCC). However, inherent resistance is observed in some patients and acquired resistance commonly develops in many patients within several months of the initiation of systemic therapies. Since these treatments rarely cure patients, their aim is to suppress tumor progression and prolong survival. Therefore, the establishment of dependable criteria that predict responses and resistance to systemic therapies is clinically important, and the underlying molecular mechanisms also need to be elucidated for the future development of more effective therapies. We herein review recent advances in research on the molecular mechanisms underlying resistance, with a focus on morphological characteristics, tumor angiogenesis, and the tumor immune microenvironment in RCC and their relationships with VEGF-TKI treatments. Recent therapies using immune checkpoint inhibitors (ICI) and newly developed VEGF-TKI also appear to be effective for advanced RCC, with stable and durable responses to ICI being observed in some RCC patients. These new drugs and their outcomes have been briefly described.

Expression and Characterization of Hyaluronan-Binding Protein Involved in Hyaluronan Depolymerization: HYBID, Alias KIAA1199 and CEMIP.

Hyaluronan (HA), a major component of the extracellular matrix in vertebrate tissues, provides structural and functional integrity to cells and organs. Biological functions of HA are dependent on the molecular size of HA and the interaction with a wide range of HA-binding proteins, i.e., hyaladherins. In this book chapter, we introduce hyaladherins and focus on HYBID (Hyaluronan-binding protein involved in hyaluronan depolymerization, alias KIAA1199 and CEMIP), which is one of the hyaladherins and plays a central role in HA degradation in human dermal and arthritic synovial fibroblasts. The protocols describe the preparation of the stable transfectants expressing HYBID, the assays of HYBID-mediated HA depolymerization, and the binding assay of HYBID to HA. These methods will be helpful to further study the HYBID-mediated biological activities and its relevance on HA degradation and turnover under various physiological and pathological conditions such as wound healing, ageing, arthritis, and cancer.

Visual liver assessment using Gd-EOB-DTPA-enhanced magnetic resonance imaging of patients in the early post-Fontan period.

No imaging modality can be used to evaluate Fontan-associated liver disease (FALD). We retrospectively reviewed hepatic gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (EOB-MRI) characteristics of patients within 1 year post-Fontan procedure, and we evaluated the association between hepatic imaging abnormalities and clinical parameters, including follow-up cardiac catheterization and laboratory test findings. The EOB-MR images were graded, based on the extent of the decreased enhancement, as "normal" (Grade 1), "segmental" (Grade 2), "regional" (Grade 3), and "diffuse" (Grade 4). We enrolled 37 patients (mean age, 3.5 ± 1.0 years): 9 patients had Grade 1 or 2; 14 patients, Grade 3; and 14 patients, Grade 4. EOB-MRI revealed characteristic reticular or mosaic patterns of diminished enhancement (i.e. "frog spawn" appearance). Ultrasonography did not detect diminished enhancement or "frog spawn" appearance. A trend existed toward increased grade severity in imaging with increased central venous pressure, pulmonary vascular resistance, and gamma-glutamyltransferase levels. Noninvasive EOB-MRI revealed the characteristic pattern of diminished enhancement, which was correlated with certain clinical parameters indicative of Fontan physiology and liver dysfunction. Early-stage FALD may occur soon after the Fontan procedure and is associated with increased pressure in the inferior vena cava and hepatic veins.

Implication of HYBID (Hyaluronan-Binding Protein Involved in Hyaluronan Depolymerization) in Hyaluronan Degradation by Synovial Fibroblasts in Patients with Knee Osteoarthritis.

Cell migration-inducing hyaluronidase 1 (CEMIP), also known as hyaluronan (HA)-binding protein involved in HA depolymerization (HYBID), plays a role in HA degradation. CEMIP2, also known as transmembrane protein 2 (TMEM2), possessing a sequence similarity with HYBID, is reported as a hyaluronidase in mice. However, the expression of these molecules in osteoarthritic synovium and their involvement in HA degradation in synovial fluid (SF) from patients with knee osteoarthritis remain elusive. This study examined their expression in synovial tissue and the relationship with molecular weight of HA in SF in knee osteoarthritis patients. Quantification of mRNA demonstrated that HYBID expression is significantly (5.5-fold) higher in osteoarthritic synovium than in normal control synovium, whereas TMEM2 expression level is similar between the two groups. By immunohistochemistry, HYBID was localized mainly to CD68-negative and fibroblast-specific protein 1-positive synovial lining cells and sublining fibroblasts in osteoarthritic synovium. The mRNA expression levels of HYBID, but not TMEM2, in osteoarthritic synovium positively correlated with distribution of lower-molecular-weight HA with below 1000 kDa in SF. HA-degrading activity in osteoarthritic synovial fibroblasts was abrogated by siRNA-mediated knockdown of HYBID. Among the 12 factors examined, IL-6 significantly up-regulated the HYBID expression and HA-degrading activity in osteoarthritic synovial fibroblasts. These data suggest that HYBID overexpressed by IL-6-stimulated synovial fibroblasts is implicated in HA degradation in osteoarthritic synovium.

HYBID (alias KIAA1199/CEMIP) and hyaluronan synthase coordinately regulate hyaluronan metabolism in histamine-stimulated skin fibroblasts.

The immune-regulatory compound histamine is involved in the metabolism of the essential skin component hyaluronan (HA). We previously reported that histamine up-regulates the expression of HYBID (hyaluronan-binding protein involved in hyaluronan depolymerization, also called CEMIP or KIAA1199), which plays a key role in HA degradation. However, no information is available about histamine's effects on HA synthase (HAS) expression, the molecular sizes of HA species produced, and histamine receptors and their signaling pathways in skin fibroblasts. Moreover, histamine's effects on photoaged skin remain elusive. Here, we show that histamine increases HA degradation by up-regulating HYBID and down-regulating HAS2 in human skin fibroblasts in a dose- and time-dependent manner and thereby decreases the total amounts and sizes of newly produced HA. Histamine H1 blocker abrogated the histamine effects on HYBID up-regulation, HAS2 suppression, and HA degradation. Histamine H1 agonist exhibited effects on HA levels, composition, and breakdown similar to those of histamine. Of note, blockade of protein kinase Cδ or PI3K-Akt signaling abolished histamine-mediated HYBID stimulation and HAS2 suppression, respectively. Immunohistochemical experiments revealed a significant ∼2-fold increase in tryptase-positive mast cells in photoaged skin, where HYBID and HAS2 expression levels were increased and decreased, respectively, compared with photoprotected skin. These results indicate that histamine controls HA metabolism by up-regulating HYBID and down-regulating HAS2 via distinct signaling pathways downstream of histamine receptor H1. They further suggest that histamine may contribute to photoaged skin damage by skewing HA metabolism toward degradation.