Byoungjae Kim

Decreased expression of E-cadherin and ZO-1 in the nasal mucosa of patients with allergic rhinitis: Altered regulation of E-cadherin by IL-4, IL-5, and TNF-alpha.

Background Allergic rhinitis is a chronic nasal inflammatory disease mediated by an immunoglobulin E mediated process to environmental allergens. Although atopy is a potent predisposing risk factor for allergic rhinitis, local tissue susceptibilities are inevitable for disease expression. The nasal epithelium maintains tissue homeostasis by providing a physical barrier controlled by epithelial junctional proteins. However, the expression of epithelial junctional proteins has not been studied in patients with allergic rhinitis. We sought to elucidate the expression and the regulation of epithelial junctional proteins in the nasal epithelium of patients with allergic rhinitis. Methods The expression of E-cadherin and zonula occludens (ZO) 1 in epithelium of turbinate was measured by using real-time polymerase chain reaction, Western blot, and immunohistochemical assays, and was compared between control subjects and patients with allergic rhinitis. In addition, the expression levels of E-cadherin and ZO-1 were determined in cultured epithelial cell treated with interleukin (IL) 4, IL-5, tumor necrosis factor (TNF) alpha, and interferon gamma. Results The expression and the immunoreactivity of E-cadherin and ZO-1 were decreased in the nasal epithelium of patients with allergic rhinitis. Interestingly, the stimulation of cultured epithelial cells with IL-4, IL-5, and TNF-alpha resulted in downregulation of E-cadherin expression only in cultured epithelial cells of patients with allergic rhinitis, whereas E-cadherin expression in cultured epithelial cells of controls was not affected by stimulation with the same panel of cytokines. Conclusion Decreased expression of epithelial junctional proteins was found in patients with allergic rhinitis. The disruption of epithelial integrity by IL-4, IL-5, and TNF-alpha in vitro indicated a possible role for these cytokines in the pathogenesis of patients with allergic rhinitis.

Ascorbic acid enhances adipogenesis of 3T3-L1 murine preadipocyte through differential expression of collagens

BackgroundAdipogenesis from preadipocytes into mature adipocyte is precisely coordinated by transcription factors such as CCAAT-enhancer-binding proteins (C/EBPs) and peroxisome proliferator-activated receptor γ (PPARγ), cytokines, and hormones, which is accompanied by extracellular matrix remodeling. Besides anti-oxidant activity, ascorbic acid (ASC) is participating in collagen biosynthesis and increase production and processing of collagens. Moreover, several studies demonstrated that ASC enhanced differentiation from preadipocytes into mature adipocytes.MethodsThe adipogenic effect of ascorbic acid was evaluated in chemical induced 3T3-L1 by Oil Red O staining. This effect was elucidated by immunoblotting which detected the expression level of collagens and transcription factors in adipogenesis. The immunocytochemical determination of type I collagen was performed in 3T3-L1 adipocyte to show the change of extracellular matrix during adipogenesis.ResultsIn this study, Oil Red O staining in 3T3-L1 preadipocytes was increased dose-dependently by addition of ASC. These ASC-treated adipocytes increased collagen processing of α1(I) and α1(V) and expressed α1(VI) and α2(VI) collagens differentially. ASC also stimulated expression of C/EBPα and PPARγ, which is preceded by collagen enhancement. In addition, inhibition of ASC activity by ethyl-3,4-dihydroxybenzoate showed reduction of lipid accumulation by removal of large lipid droplets, not by inhibition of lipid production. This observation went with loss of α1(I) deposition on adipocyte surface, increase of α1(V) and α2(VI) collagens and decrease of C/EBPs.ConclusionOur findings imply that various actions of ASC on adipogenesis through differential collagen expression may provide diverse applications of ASC to adipose tissue technology.

In vivo photothermal treatment by the peritumoral injection of macrophages loaded with gold nanoshells.

Photothermal treatment methods have been widely studied for their target specificity and potential for supplementing the limitations of conventional surgical treatments. In this study, we conducted in vivo photothermal treatments using macrophages containing nanoshells as live vectors. We injected macrophages at the peritumoral sites and observed that they had penetrated into the tumor approximately 48 hours after injection. Afterwards, we irradiated with a near-infrared laser for 2 minutes at 1 W/cm(2), causing cancer cell death. Our study identified the optimal conditions of the photothermal treatment and confirmed the feasibility of its use in in vivo treatments.

Effect of 1-methyl-D-tryptophan and adoptive transfer of dendritic cells on polymicrobial sepsis induced by cecal content injection

A mouse model of polymicrobial sepsis induced by cecal content injection (CCI) was developed with the aim of gaining a better understanding of the mechanism of sepsis. This model has a similar survival pattern to the conventional model with the added benefits of ability to vary the severity of sepsis and greater consistency. Administration of 1‐methyl‐D‐tryptophan (1‐MT) to inhibit indoleamine 2,3‐dioxygenase (IDO) in mice with CCI‐induced sepsis increased the survival rate and tended to up‐regulate IL‐10/IL‐12 serum concentrations. The effectiveness of 1‐MT was confirmed by increases in IL‐10 over IL‐12 in bone marrow‐derived dendritic cells (BMDCs) treated with LPS and 1‐MT and a superior survival rate 24 hr after injection of these double treated BMDCs in the CCI‐induced sepsis model. Therefore, CCI is both a useful and reliable technique for investigating polymicrobial sepsis. The present findings using this newly developed model suggest that inhibition of IDO alleviates the severity of polymicrobial sepsis and modulates the immune response even in cases of severe systemic septic inflammation.

Adipogenic and lipolytic effects of ascorbic acid in ovariectomized rats

Purpose Ascorbic acid has been reported to have an adipogenic effect on 3T3-L1 preadipocytes, while evidence also suggests that ascorbic acid reduces body weight in humans. In this study, we tested the effects of ascorbic acid on adipogenesis and the balance of lipid accumulation in ovariectomized rats, in addition to long-term culture of differentiated 3T3-L1 adipocytes. Materials and Methods Murine 3T3-L1 fibroblasts and ovariectomized rats were treated with ascorbic acid at various time points. In vitro adipogenesis was analyzed by Oil Red O staining, and in vivo body fat was measured by a body composition analyzer using nuclear magnetic resonance. Results When ascorbic acid was applied during an early time point in 3T3-L1 preadipocyte differentiation and after bilateral ovariectomy (OVX) in rats, adipogenesis and fat mass gain significantly increased, respectively. However, lipid accumulation in well-differentiated 3T3-L1 adipocytes showed a significant reduction when ascorbic acid was applied after differentiation (10 days after induction). Also, oral ascorbic acid administration 4 weeks after OVX in rats significantly reduced both body weight and subcutaneous fat layer. In comparison to the results of ascorbic acid, which is a well-known cofactor for an enzyme of collagen synthesis, and the antioxidant ramalin, a potent antioxidant but not a cofactor, showed only a lipolytic effect in well-differentiated 3T3-L1 adipocytes, not an adipogenic effect. Conclusion Taking these results into account, we concluded that ascorbic acid has both an adipogenic effect as a cofactor of an enzymatic process and a lipolytic effect as an antioxidant.

Fundamental role of dendritic cells in inducing Th2 responses

A mysterious puzzle in immunology is how the immune system decides what types of immune response to initiate against various stimuli. Although much is known about control of T helper 1 (Th1) and Th17 responses, the mechanisms that initiate Th2 responses remain obscure. Antigen-presenting cells, particularly dendritic cells (DCs), are mandatory for the induction of a Th cell response. Numerous studies have documented the organizing role of DCs in this process. The present review summarizes the fundamental roles of DCs in inducing Th2 responses.

Decreased expression of CCL17 in the disrupted nasal polyp epithelium and its regulation by IL-4 and IL-5

Background In airway epithelium, thymus and activation-regulated chemokine (CCL17) and macrophage-derived chemokine (CCL22) are induced by defective epithelial barriers such as E-cadherin and attract the effector cells of Th2 immunity. However, the association between the epithelial barrier and CCL17 expression has not been studied in chronic rhinosinusitis with nasal polyp (CRSwNP). Thus, we aimed to evaluate the expression of CCL17 and its regulation by Th cytokines in nasal polyp (NP) epithelial cells. Methods The expression and distribution of CCL17, CCL22, E-cadherin and/or epidermal growth factor receptor (EGFR) were measured using real-time PCR, western blot, and immunohistochemistry and compared between normal ethmoid sinus epithelium and NP epithelium. In addition, the expression level of CCL17 was determined in cultured epithelial cells treated with IL-4, IL-5, IL-13, TNF-α, and IFN-γ. Results The expression of CCL17 was decreased in the NP epithelium compared to the epithelium of normal ethmoid sinus, whereas the expression of CCL22 was not decreased. E-cadherin was differentially distributed between the epithelium of normal ethmoid sinus and NP epithelium. EGFR was also decreased in NPs. Interestingly, the stimulation of cultured epithelial cells with Th2 cytokines, IL-4 and IL-5, resulted in an upregulation of CCL17 expression only in NP epithelial cells whereas the expression of CCL17 was increased in both normal epithelial cells and NP epithelial cells by Th1 cytokines. Conclusion Our results suggest that the decreased expression of CCL17 in defective NP epithelium may be closely connected to NP pathogenesis and can be differentially regulated by cytokines in the NP epithelium of patients with CRSwNP.

Effect of matrix metalloproteinase inhibitor on disrupted E-cadherin after acid exposure in the human nasal epithelium

Laryngopharyngeal reflux disease (LPRD) is one of potential factors in recalcitrant chronic rhinosinusitis with or without polyps. An increase in junctional permeability in the nasal mucosa in LPRD may be due to disrupted protein bridge formation with cell‐to‐cell adhesion molecules such as E‐cadherin. Despite the relationship between nasal mucosal inflammation and LPRD, the clear mechanism by which acid reflux affects the nasal epithelium remains unclear.

Excitatory GABAergic action and increased vasopressin synthesis in hypothalamic magnocellular neurosecretory cells underlie the high plasma level of vasopressin in diabetic rats

Diabetes mellitus (DM) is associated with increased plasma levels of arginine-vasopressin (AVP), which may aggravate hyperglycemia and nephropathy. However, the mechanisms by which DM may cause the increased AVP levels are not known. Electrophysiological recordings in supraoptic nucleus (SON) slices from streptozotocin (STZ)-induced DM rats and vehicle-treated control rats revealed that γ-aminobutyric acid (GABA) functions generally as an excitatory neurotransmitter in the AVP neurons of STZ rats, whereas it usually evokes inhibitory responses in the cells of control animals. Furthermore, Western blotting analyses of Cl− transporters in the SON tissues indicated that Na+-K+-2Cl– cotransporter isotype 1 (a Cl− importer) was upregulated and K+-Cl– cotransporter isotype 2 (KCC2; a Cl− extruder) was downregulated in STZ rats. Treatment with CLP290 (a KCC2 activator) significantly lowered blood AVP and glucose levels in STZ rats. Last, investigation that used rats expressing an AVP-enhanced green fluorescent protein fusion gene showed that AVP synthesis in AVP neurons was much more intense in STZ rats than in control rats. We conclude that altered Cl− homeostasis that makes GABA excitatory and enhanced AVP synthesis are important changes in AVP neurons that would increase AVP secretion in DM. Our data suggest that Cl− transporters in AVP neurons are potential targets of antidiabetes treatments.

In vivo photothermal treatment with real-time monitoring by optical fiber-needle array

Photothermal treatment (PTT) using gold nanoshells (gold-NSs) is accepted as a method for treating cancer. However, owing to restrictions in therapeutic depth and skin damage caused by excessive light exposure, its application has been limited to lesions close to the epidermis. Here, we demonstrate an in vivo PTT method that uses gold-NSs with a flexible optical fiber-needle array (OFNA), which is an array of multiple needles in which multimode optical fibers are inserted, one in each, for light delivery. The light for PTT was directly administrated to subcutaneous tissues through the OFNA, causing negligible thermal damage to the skin. Enhancement of light energy delivery assisted by the OFNA in a target area was confirmed by investigation using artificial tissues. The ability of OFNA to treat cancer without causing cutaneous thermal damage was also verified by hematoxylin and eosin (H&E) staining and optical coherence tomography in cancer models in mice. In addition, the OFNA allowed for observation of the target site through an imaging fiber bundle. By imaging the activation of the injected gold-NSs, we were able to obtain information on the PTT process in real-time.