Phosphorylation of p27(KIP1) in the Mitotic Cells of the Corneal Epithelium

PURPOSE

The mechanism in regulation of the cell cycle and proliferation of corneal epithelium in the homeostatic ocular surface remains unclear. The aim of this study is to examine the expression of p27(KIP1) and its phosphorylation in corneal epithelium.

METHODS

The eyes of C57BL/6 mice (7 weeks old) were enucleated. Formalin-fixed and paraffin-embedded tissue sections were examined using immunohistochemistry with anti-p27(KIP1), threonine 187 phosphorylated p27(KIP1) (T187-phospho-p27), and phosphorylated Histon H3 (pHiston H3) antibodies. Anti-T187-phospho-p27 and anti-pHiston H3 polyclonal antibodies were used for parallel immunofluorescent staining.

RESULTS

pHiston H3-immunopositive cells were noted in basal cells of the corneal epithelium. At high magnification of DAPI nuclear staining, mitotic and non-mitotic cells were observed in corneal basal layer. p27(KIP1)-positive nuclei were detected in corneal basal cells, where non-mitotic basal cells were located. In contrast, mitotic cells showed under detectable level on p27(KIP1) immunoreactivity. Immunoreactivity for T187-phospho-p27 was detected in basal cells of the corneal epithelium. At high magnification, it was confirmed that the immunopositive cells were mitotic cells. Immunoreactivity of T187-phospho-p27 as well as pHiston H3 was localized in the same corneal basal cells using double-staining immunohistochemistry.

CONCLUSIONS

These results suggested that degradation of p27(KIP1) regulates progression into mitosis in corneal basal cells.

EXTL3 promoter methylation down-regulates EXTL3 and heparan sulphate expression in mucinous colorectal cancers

Exostoses like-3 (EXTL3) is a putative tumour suppressor gene but its involvement in colorectal cancer (CRC) is unclear. We have investigated the role of methylation of the EXTL3 promoter as a mechanism for EXTL3 regulation and tested the hypothesis that loss of EXTL3 expression is associated with mucinous differentiation and alteration of glycoprotein expression in CRC cells. The methylation status of the EXTL3 gene promoter was analysed by methylation-specific PCR following bisulphite modification in CRC cell lines and microdissected primary CRC tissues and their corresponding adjacent normal colorectal mucosa. EXTL3 promoter methylation was detected in seven of 11 mucinous CRCs (63.6%) but in none of 26 non-mucinous CRCs examined. EXTL3 promoter methylation was also detected in the normal colonic mucosa of three patients with mucinous CRC but not in the normal colonic mucosa of any patients with non-mucinous CRC. The presence of EXTL3 methylation was significantly associated with the partial loss of HS expression in mucinous CRC lesions. The mucinous CRC cell lines, Colo201 and Colo205, showed EXTL3 promoter methylation and loss of EXTL3 mRNA expression. However 5-aza-2'-deoxycytidine treatment demethylated the EXTL3 gene promoter and restored its mRNA expression. Furthermore, the basal expression of HS in CRC cells was abolished by treatment with EXTL3-siRNA. We conclude that EXTL3 promoter methylation and its related loss of EXTL3 expression are involved in the loss of HS expression in mucinous CRCs.

Phosphorylation of p27(KIP1) in lens epithelial cells after extraction of fiber cells

Opacification of the posterior capsule depends on replication of the residual lens epithelial cells lining the capsule. However, the mechanisms in the regulation of lens cell proliferation have not been determined. The purpose of this study is to examine the expression of p27(KIP1), a cyclin-dependent kinase inhibitor, and its phosphorylation, and cyclin D1 in lens epithelial cells after extraction of fiber cells. C57Bl6 mice (12 weeks old) were anesthetized, and the lens fiber cells were surgically extracted. Eyeballs were collected and fixed at 15 min and 24 h after extraction with and without injection of a specific phosphorylated extracellular signal-regulated kinase (pERK) 1/2 inhibitor (PD98059) to the anterior chamber. Collected tissues were analyzed using immunohistochemistry with anti-p27(KIP1), anti-phosphorylated p27(KIP1) on serine 10 (s10-phospho-p27) and cyclin D1 antibodies. Human lens epithelial cells were cultured, and then were treated with and without 40 ng/ml human recombinant basic fibroblast growth factor (bFGF), which was analyzed by Western blot analysis. In the untreated lens, p27(KIP1) was not phosphorylated in the lens epithelial cells, although p27(KIP1)-positive nuclei were detected in the lens cells of the equatorial region. Immunoreactivity for cyclin D1 was hardly detected in the lens. Nuclear immunoreactivity for p27(KIP1) and s10-phospho-p27 was observed in several lens cells of the equatorial region 15 min after extraction of fiber cells. Western blotting demonstrated that the p27(KIP1) phosphorylation form was upregulated 15 min after bFGF treatment in cultured lens epithelial cells. Many cyclin D1-positive nuclei were noted 24 h after the surgery. p27(KIP1) phosphorylation and cyclin D1 induction were inhibited by PD98059. s10-phospho-p27 and p27(KIP1) immunoreactivity was undetected in the lens cells 24 h after the extraction of fiber cells. It is possible that the phosphorylation of p27(KIP1), and cyclin D1 expression are regulated by the ERK pathway in lens cells after the extraction of fiber cells.

Inhibition of nuclear factor-kappa B activation attenuates hydrogen peroxide-induced cytotoxicity in human lens epithelial cells

AIMS

Hydrogen peroxide (H(2)O(2)) is the major oxidant involved in cataract formation. Lens epithelial cells have been suggested to be the first site of oxidative damage. The authors investigated the relationship between H(2)O(2)-induced cytotoxicity and activation of nuclear factor kappa B (NF-kappaB) in human lens epithelial (HLE) cells.

METHODS

HLE B-3 cells were stimulated by various concentrations of H(2)O(2) in the presence or absence of pyrrolidine dithiocarbamate (PDTC), a potent inhibitor of NF-kappaB. H(2)O(2)-induced cytotoxicity was measured by lactate dehydrogenase cytotoxicity assay. Translocation of NF-kappaB was examined by Western blot and immunocytochemistry using anti-p65 antibody.

RESULTS

H(2)O(2)-induced cytotoxicity increased in a concentration-dependent manner. PDTC treatment significantly suppressed the cytotoxicity induced by H(2)O(2). After stimulated with H(2)O(2), NF-kappaB was found translocated from cytoplasm into the nuclei. PDTC treatment also inhibited the translocation of NF-kappaB.

CONCLUSIONS

NF-kappaB signal pathway may be important in the development of H(2)O(2)-induced damage in HLE cells that is involved in cataractogenesis.

Captopril suppresses inflammation in endotoxin-induced uveitis in rats

Captopril is an inhibitor of angiotensin-converting enzyme (ACE) that is largely used in the treatment of cardiovascular diseases. Several previous studies have demonstrated that captopril exhibits a wide variety of biological activities, including an anti-inflammatory action, on which we focused our attention. The aim of the present study was to investigate the efficacy of captopril on endotoxin induced uveitis (EIU) in rats. We investigated its effect upon cellular infiltration and protein leakage, as well as on the concentration of tumor necrosis factor-alpha (TNF-alpha), nitric oxide (NO), prostaglandin E2 (PGE2), monocyte chemoattractant protein-1 (MCP-1) in the anterior chamber. In addition, we checked its effect on activation of nuclear factor kappa B (NF-kappaB) in iris and ciliary body (ICB) cells in vivo. EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). One hour after the LPS inoculation, either 1mg/kg, 10mg/kg or 100mg/kg captopril were injected intravenously. 24h later, the aqueous humor was collected from both eyes, and the number of infiltrating cells and protein concentration in the aqueous humor were determined. Levels of TNF-alpha, PGE2, NO and MCP-1 were determined by enzyme-linked immunosorbent assay. On some eyes, after enucleation, immunohistochemical staining with a monoclonal antibody against activated NF-kappaB was performed. Captopril treatment significantly decreased the inflammatory cells infiltration, the level of protein, concentrations of TNF-alpha, PGE2, NO and MCP-1 in the aqueous humor. The number of activated NF-kappaB-positive cells was lower in ICB of the rats treated with captopril 3h after the LPS injection. The present results indicate that captopril suppresses the inflammation in EIU by inhibiting the NF-kappaB-dependent pathway and the subsequent production of pro-inflammatory mediators.

Inhibitory effects of lutein on endotoxin-induced uveitis in Lewis rats

PURPOSE

Lutein deposits in the macula and lens of human eyes with high concentration and is well known as an eye-protective nutrient for its beneficial effects on eye disease such as age-related macular degeneration and cataract. The purpose of the present study was to investigate the effects of lutein on endotoxin-induced uveitis (EIU) in rats.

METHODS

EIU was induced in male Lewis rats by subcutaneous injection of 200 microg lipopolysaccharide. Lutein or dexamethasone was administered intravenously at 30 minutes before, at the same time as, and at 30 minutes after LPS treatment. The aqueous humor was collected at 24 hours after LPS injection, the number of infiltrating cells, the protein concentration, and the levels of nitric oxide (NO), tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, prostaglandin (PG)-E2, monocyte chemoattractant protein-1 (MCP-1), and macrophage inflammatory protein (MIP)-2 in the aqueous humor were determined. Immunohistochemical staining with a monoclonal antibody against activated nuclear factor (NF)-kappaB was performed to evaluate the effect of lutein on NF-kappaB activation in the iris-ciliary body (ICB) of rats. A mouse macrophage cell line (RAW264.7 cells) was stimulated with LPS in the presence or absence of lutein. Expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and degradation of inhibitor kappaB (IkappaB) were analyzed by Western blot analysis.

RESULTS

Lutein suppressed the development of EIU in a dose-dependent fashion. The anti-inflammatory effect of 100 mg/kg lutein was as strong as that of 1 mg/kg dexamethasone. Treatment with lutein reduced the concentrations of NO, TNF-alpha, IL-6, PGE2, MCP-1, and MIP-2 in aqueous humor. Lutein also suppressed the activation of NF-kappaB in the ICB as well as iNOS and COX-2 expression and IkappaB degradation in RAW cells.

CONCLUSIONS

These findings indicate that lutein has anti-inflammatory effects on EIU by inhibiting the NF-kappaB dependent signaling pathway and the subsequent production of proinflammatory mediators.

Expression of cdc2 and p27(KIP1) phosphorylation in mitotic cells of the human retinoblastoma

It was recently demonstrated that a lack of p27(KIP1) degradation resulted in the suppression of cdc2 activity and consequent inhibition of entry into the M-phase. The aim of this study was to examine the distribution of phosphorylated p27(KIP1) on threonine 187 (T187-phospho-p27) and cdc2 in mitotic cells of human retinoblastoma, a malignant retinal neoplasm. Several T187-phospho-p27-immunopositive cells were observed in mitotic retinoblastoma cells, but not in the normal retina. Immunoreactivity for T187-phospho-p27 was located in the prophase and metaphase of mitotic tumor cells. In contrast, tumor cells in the anaphase showed no immunoreactivity for T187-phospho-p27. Nuclear expression of cdc2 was detected in many retinoblastoma cells, including mitotic cells. The immunoreactivity in mitotic cells was located in the prophase, as well as metaphase. In contrast, anaphase cells did not show immunoreactivity. Double staining demonstrated the same localization of T187-phospho-p27 and cdc2 in mitotic cells. These results suggest that p27(KIP1) interacts with cdc2 in the M-phase of human retinoblastoma cells.

[Mitral valvuloplasty utilizing a posterior leaflet patch for healed infective endocarditis; report of a case]

A 63-year-old man was diagnosed as having grade IV mitral regurgitation (MR). Intraoperative examination revealed perforation (13x7 mm) of the anterior mitral leaflet (AML) and prolapse of the posterior mitral leaflet (PML). The prolapsing part of the PML was resected as a rectangle and the AML perforation was covered with this resected PML patch. A Carpentier-Edwards rigid ring (30 mm) was used to secure the mitral valve annulus after suturing the PML. The patient had an uneventful course after surgery and postoperative echocardiography showed no regurgitation.

Granulocytapheresis in patients with refractory ocular Behcet's disease

Intraocular inflammation (uveoretinitis) is one major complication of Behcet's disease (BD) and responds poorly to drug therapy. This open prospective study was to assess the efficacy of selective granulocytapheresis in patients with refractory uveoretinitis of BD. Fourteen patients aged 20-56 years were treated. Granulocytapheresis was done with an Adacolumn filled with cellulose acetate leucocyte carries or beads that adsorb granulocytes and monocytes from the blood in the column. Each patient received 5 Adacolumn sessions at one session/week over 5 consecutive weeks. The study was designed to allow each patient to serve as his or her own control. The total numbers of ocular attacks (OA) were monitored for 6 months before and after 5 Adacolumn sessions. The number of OA (mean +/- SD) per patient for the 6 months before Adacolumn was 4.21 +/- 1.6 and for the 6 months post Adacolumn was 2.93 +/- 1.39 ( P = 0.0275). Nine patients (64%) improved and 5 did not change or worsened. Further, for a sub-group (n = 7) with duration of BD > or =5 years, the number of OA were 4.71 +/- 1.89 for the first 6 months and 2.29 +/- 1.38 for the second 6 months ( P = 0.0054). The corresponding values for a sub-group (n = 7) with duration of BD<5 years were 3.71 +/- 1.25 and 3.57 +/- 1.13, indicating that patients with long duration of BD are better responders. We conclude that granulocytapheresis might be effective and safe for patients with refractory ocular BD. Further studies are necessary to fully evaluate the clinical efficacy of granulocytapheresis for BD.

Increase in macrophage migration inhibitory factor levels in lacrimal fluid of patients with severe atopic dermatitis

BACKGROUND AND AIMS OF THE STUDY

Atopic dermatitis is a chronic inflammatory skin disorder that often involves some ophthalmic features. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that is associated with the generation of cell-mediated immune responses. Although serum MIF levels may be elevated in severe atopic dermatitis, the quantity of MIF in regional ocular fluid remains unknown. We measured MIF levels in tears (lacrimal fluid) of patients with atopic dermatitis.

PATIENTS AND METHODS

Tear samples were collected from 16 patients with atopic dermatitis, 10 patients with allergic conjunctivitis, and 15 healthy control subjects. The clinical severity of atopic dermatitis was evaluated according to the Scoring Atopic Dermatitis (SCORAD) index. The index was calculated by summing the following scores: extent criteria, intensity criteria, and subjective symptoms. Macrophage migration inhibitory factor levels were determined by a human MIF enzyme-linked immunosorbent assay. All comparisons were two-tailed, and P values <0.01 were considered as statistically significant.

RESULTS

The mean MIF concentration in lacrimal fluid collected from healthy control subjects was 0.69+/-0.2 ng/ml. The mean tear MIF levels were 17.87+/-6.3 ng/ml in moderate-to-severe atopic dermatitis (SCORAD> or =15, P=0.002), 0.93+/-0.08 ng/ml in mild atopic dermatitis (SCORAD<15), and 2.76+/-0.86 ng/ml in allergic conjunctivitis (P=0.008).

CONCLUSIONS

A proinflammatory cytokine MIF level was elevated in tears as well as serum in cases of severe atopic dermatitis. These results suggest that MIF may play an important role in the induction or enhancement of ophthalmic features related to severe atopic dermatitis.

Immunolocalization of cyclin D1 in the developing lens of c-maf -/- mice

The maf gene encodes a transcription factor protein containing a typical basic/leucine zipper domain structure, a motif for protein dimerization and DNA binding. It has been demonstrated that maf family genes have important roles in embryonic development and cellular differentiation. In this study, localization of cyclin D1, one of the cell cycle-related molecules, was examined immunohistochemically in developing lens cells of c-maf knockout (-/-) mice. At embryonic day 14 in wild-type mice, lens cells consisted of round epithelial cells in a single layer and regularly arranged elongated lens cells, indicating primary lens fiber cells. Cyclin D1-positive nuclei were observed in the lens epithelial cells, whereas cyclin D1 was not detected in the primary lens fiber cells. In c-maf -/- mice, a variety of round epithelial cells were located in the anterior and posterior lens. Many cyclin D1-positive nuclei were observed in lens epithelial cells as well as posterior lens cells. These results are consistent with c-maf playing a role in the regulation of cyclin D1 in developing lens cells.

Effects of blue honeysuckle (Lonicera caerulea L.) extract on lipopolysaccharide-induced inflammation in vitro and in vivo

The aim of the present study was to investigate the effects of blue honeysuckle extract (BHE), which contains high level of phenolic compounds, on endotoxin-induced uveitis (EIU). Male Lewis rats were randomly divided into 5 groups with 14 rats in each (eight rats for collection of aqueous humor, six rats for histologic examination). EIU was induced by a footpad injection of lipopolysaccharide (LPS). 1, 10, or 100 mg of BHE was injected intravenously immediately after LPS injection. The aqueous humor was collected at 24 h after LPS injection, the number of infiltrating cells, protein concentration, nitric oxide (NO), tumor necrosis factor (TNF)-alpha, and prostaglandin (PG)-E2 levels in the aqueous humor were determined. Some eyes were enucleated for histologic examination and immunohistochemical analysis. Immunohistochemical staining with a monoclonal antibody against activated nuclear factor (NF)-kappaB was performed to evaluate the effect of BHE on NF-kappaB activation. To further clarify the anti-inflammatory effect, RAW264.7 cells (a mouse macrophage cell line) were stimulated with LPS in the presence or absence of BHE and its major phenolics, cyanidin 3-glucoside (C3G), cyanidin 3-rutinoside (C3R), chlorogenic acid (CA). Expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) were analyzed by Western blot method. BHE treatment significantly reduced the inflammatory cell infiltration, the protein concentration, the levels of NO, TNF-alpha and PGE2 in the aqueous humor and improved histologic status of the ocular tissue. The number of activated NF-kappaB-positive cells was lower in the iris-ciliary body treated with BHE at 3 h after LPS injection. BHE significantly suppressed the production of NO, PGE2 and TNF-alpha in the culture medium as well as the expression of iNOS and COX-2 by LPS-stimulated RAW264.7 cells in a dose-dependent fashion. C3G, C3R and CA showed no or weak inhibitory effects on the level of inflammatory mediators and the expression of iNOS and COX-2. These results suggest that BHE attenuates the degree of inflammation in eyes with EIU by inhibiting the NF-kappaB dependent signaling pathway and the subsequent production of proinflammatory mediators.

Expression of p27(KIP1) and cell proliferation in human retina and retinoblastoma

BACKGROUND

Retinoblastoma is a rare cancer of the eye, in which biallelic inactivation of the retinoblastoma gene is a hallmark. Although retinoblastoma protein (Rb) and p27(KIP1) block the cell cycle transition from G1- to S-phase, the interaction has not been confirmed in vivo. The aim of this study was to examine the correlation between the expression of p27(KIP1) and cell proliferation in human retina and retinoblastoma.

MATERIALS AND METHODS

Human retinoblastoma, surgically removed, was fixed by 4% paraformaldehyde. Then, paraffin-embedded tissue sections were examined using immunohistochemistry with anti-p27(KIP1) and anti-proliferating cell nuclear antigen (PCNA) antibodies.

RESULTS

Retinoblastoma tissue was adjacent to the normal retina in which tumor cells with homogeneous nuclei proliferated and it was impossible to identify the layer structure of the inner nuclear layer (INL) and the outer nuclear layer (ONL). In normal retina, PCNA-positive nuclei were not observed, whereas nuclear immunoreactivity for PCNA was detected in a variety of tumor cells. Many p27(KIP1)-positive nuclei were detected in INL and ONL, while p27(KIP1) immunoreactivity was not detected in retinoblastoma cells.

CONCLUSION

The correlation between disappearance of p27(KIP1) and induction of proliferation activity suggests that functional loss of Rb leads to down-regulation of p27(KIP1) and uncontrolled retinal cell proliferation.

Disappearance of p27(KIP1) and increase in proliferation of the lens cells after extraction of most of the fiber cells of the lens

PURPOSE

Proliferation of the lens epithelial cells is involved in the fibrotic changes of lens capsules after cataract extraction. However, the mechanisms of the proliferation of the lens epithelial cells are largely unknown. The purpose of this study was to examine the correlation between the expression of p27(KIP1) and cell proliferation in the lens cells after the extraction of lens fiber cells.

METHODS

At embryonic days (E) 14 and 18, the C57Bl6 mice were anesthetized and the embryos were surgically removed. The eyes were dissected from these embryos and also from mice 12 weeks after birth. The 12-week-old mice were anesthetized, and then the lens fiber cells were extracted. Normal eyes at E14 and 18 and eyes fixed at 15 min and 48 hr after the extraction of the lens fiber cells were analyzed using immunohistochemistry with anti-p27(KIP1), p57(KIP2), and phosphorylated extracellular signal-regulated kinase (phospho-ERK) 1/2 antibodies, and cells in the S phase of the cell cycle were also examined using anti-bromodeoxyuridine (BrdU) antibody.

RESULTS

p27(KIP1) and p57(KIP2)-positive cells were present in the equatorial region of E14 mice. At E18, many lens fiber cells showed nuclear immunoreactivity for p27(KIP1), whereas a small number of cells were positive for p57(KIP2) in the equatorial region. At 12 weeks of age, all nuclei of the lens epithelial cells as well as lens fiber cells showed nuclear immunoreactivity for p27(KIP1). In contrast, p57(KIP2) and phospho-ERK1/2 were not expressed in the lens cells. At 15 min after the extraction of lens fiber cells, phospho-ERK1/2 as well as p27(KIP1) were detected in the lens cells. At 48 hr after the extraction of the lens fiber cells, a few p27(KIP1)-positive nuclei were observed in the equatorial region of the lens capsule. In contrast, many lens cells showed nuclear immunoreactivity for BrdU.

CONCLUSIONS

These findings suggest that degradation of p27(KIP1) mediated by phosphorylation of ERK 1/2 is correlated with proliferation of the epithelial cells after the extraction of the lens fiber cells.

Expression of thymidine phosphorylase in choroidal malignant melanoma associated with neovascular glaucoma

Reported herein is a case of 62-year-old man who complained of blurred vision and ocular pain in his right eye. The patient was diagnosed with choroidal melanoma complicated by neovascular glaucoma (NVG) and total retinal detachment, and he underwent enucleation of the eye. The isolated tumor was 2.5 x 2.5 cm in size. It was accompanied by intratumoral calcification, and consisted of epithelioid and spindle melanoma cells. There were a variety of microvessels in the stroma of the iris. The expression of thymidine phosphorylase (dThdPase), an angiogenic factor, was examined immunohistochemically. Cytoplasmic immunoreactivity for dThdPase was more prominent in the epithelioid cells than in spindle tumor cells. Another case of choroidal melanoma without NVG had less marked immunoreactivity. These results suggest that the production of dThdPase by melanoma cells correlates with the pathogenesis of NVG.

Suppressive effects of astaxanthin against rat endotoxin-induced uveitis by inhibiting the NF-kappaB signaling pathway

We investigated the effects of astaxanthin (AST), a carotenoid, on endotoxin-induced uveitis (EIU), and over the course of the disease measured the expression of inflammatory cytokines and chemokines in the presence or absence of AST. EIU was induced in male Lewis rats by footpad injection of lipopolysaccharide (LPS). The animals were randomly divided to 12 groups with eight animals in each. Immediately after the inoculation, AST (1, 10, or 100 mg kg(-1)) was injected intravenously. Aqueous humour was collected at 6, 12 and 24 hr after LPS inoculation and the number of infiltrating cells in the anterior chamber was counted. In addition, we assayed the concentration of protein, nitric oxide (NO), tumour necrosis factor-alpha (TNF-alpha) and prostaglandin E2 (PGE2). Immunohistochemical staining with a monoclonal antibody against activated NF-kappaB was performed in order to evaluate the effects of AST on NF-kappaB activation. Rats injected with AST showed a significant decrease in the number of infiltrating cells in the anterior chamber and additionally there was a significantly lower concentration of protein, NO, TNF-alpha and PGE2 in the aqueous humour. Moreover, even early stages of EIU were suppressed by injection of AST. The number of activated NF-kappaB-positive cells was lower in iris-ciliary bodies treated with 10 or 100 mg kg(-1) AST at 3 hr after LPS injection. These results suggest that AST reduces ocular inflammation in eyes with EIU by downregulating proinflammatory factors and by inhibiting the NF-kappaB-dependent signaling pathway.

Phosphorylation of extracellular signal-regulated kinase and p27(KIP1) after retinal detachment

PURPOSE

The roles of the extracellular signal-regulated kinase (ERK) pathway in the expression of cyclin D1 and p27(KIP1), the phosphorylation of p27(KIP1), and proliferation activity were examined after retinal detachment.

METHODS

Normal eyes and eyes at 15 min, 2 and 4 days after retinal detachment in C57Bl6 mice were examined by immunohistochemistry using anti-phosphorylated (p) ERK1/2, anti-cyclin D1, anti-p27(KIP1), anti-p27(KIP1) phosphorylated at serine 10 (S10-phospho-p27), and anti-proliferating cell nuclear antigen (PCNA) antibodies with or without treatment with a specific ERK inhibitor, PD98059. Mouse Müller cells were isolated and examined for alteration of p27(KIP1) and cyclin D1 after exposure of basic fibroblast growth factor (bFGF) with and without treatment of PD98059 using Western blotting.

RESULTS

In the normal retina, nuclear immunoreactivity for p27(KIP1), but not S10-phospho-p27 or pERK1/2, was observed in the middle sublayer of the inner nuclear layer (INL), where Müller glial cells are situated. At 15 min after the retinal detachment, p27(KIP1), S10-phospho-p27 and pERK1/2-positive nuclei were noted in the INL, whereas immunoreactivity for pERK1/2 or S10-phospho-p27 was not observed after treatment with PD98095. Cyclin D1 was induced in the INL 2 days after the retinal detachment, and the induction was inhibited by PD98059. At 4 days after the detachment, p27(KIP1) immunoreactivity was not observed, and cyclin D1 and PCNA were expressed. The disappearance of p27(KIP1) was suppressed, whereas expression of cyclin D1 and PCNA was not observed in mice treated with PD98059. Exposure of bFGF relatively decreased the expression level of p27(KIP1) and increased the level of cyclin D1 in mouse Müller cells, compared with control level. Induction of cyclin D1 and decrease in p27(KIP1) were inhibited with treatment of PD98059.

CONCLUSION

Phosphorylation of ERK and expression of p27(KIP1) and cyclin D1 are involved in the proliferation of Müller cells after retinal detachment.

Phosphorylation of p27(KIP1) in the developing retina and retinoblastoma

Cellular distribution of the p27(KIP1) protein and its phosphorylation on threonine (T) 187 in mouse retinas from three stages of development, and retinoblastoma were examined. Retinas in C57Bl6 mice at embryonic day (E) 14, postnatal day (P) 1 and P11 were analyzed using immunohistochemistry with anti-p27(KIP1), threonine-187-phosphorylated p27(KIP1) (T187-phospho-p27), bromodeoxyuridine (BrdU), proliferating cell nuclear antigen (PCNA) antibodies, and phosphorylated histon H3 (pHiston H3), which is a marker for cells in M phase. p27(KIP1) knockout (-/-) mice and human retinoblastoma were also analyzed. T187-phospho-p27 was detected in the outermost layer of the retina, whereas several neuroblastic cells expressed p27(KIP1) at E14. Many neuroblastic cells expressed BrdU in the middle layer. At P1, p27(KIP1) was detected in the ganglion cell layer and neuroblastic layer. T187-phospho-p27 was detected in the outermost layer, and that was localized in mitotic cells that also showed pHiston H3-positive. At P11, p27(KIP1) was detected in the inner nuclear layer, whereas T187-phospho-p27-positive or mitotic cells were not. BrdU positive nuclei were not detected in wild-type but were noted in the inner nuclear layer and the outer nuclear layer of the p27(KIP1) -/- mice retina at P11. In retinoblastoma, tumor cells formed numerous rosettes with Flexner-Wintersteiner rosettes. Several pHiston H3 -positive nuclei were noted in the tumor cells forming Flexner-Wintersteiner rosettes. Several T187-phospho-p27-positive nuclei were also detected in the mitotic cells forming Flexner-Wintersteiner rosettes. PCNA was expressed in rosette-forming cells. In conclusion, T187-phospho-p27(KIP1) was correlated with M phase of the cell cycle in the developing retina and retinoblastoma.

The Effects of Naringin and Naringenin on Endotoxin-Induced Uveitis in Rats

The aim of this study was to investigate the efficacy of naringin and naringenin on endotoxin- induced uveitis (EIU) in rats. EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). The rats were injected intravenously with 0.4, 4, or 40 microg/kg naringin or naringenin. Each compound was administered three times, simultaneously, 30 min before and after the actual LPS injection. The aqueous humor was collected 24 h later from both eyes, and the number of cells infiltrating into the aqueous humor and the aqueous humor protein concentration were measured. The levels of prostaglandin E2 (PGE2) and nitric oxide (NO) were determined. Naringin and naringenin suppressed the development of EIU in a dose-dependent fashion. Both treatments with naringin and naringenin produced reductions in PGE2 and NO concentrations in the aqueous humor. In particular, 40 microM/kg of naringin and naringenin suppressed increases in cell count owing to LPS treatment by 31% and 38%, respectively. The possible mechanism for the antiocular inflammatory effect may be the suppression of PGE2 and NO by naringin and naringenin.

Anti-inflammatory effects of alpha-melanocyte-stimulating hormone against rat endotoxin-induced uveitis and the time course of inflammatory agents in aqueous humor

PURPOSE

We examined the effects of the immunosuppressive neuropeptide alpha-melanocyte stimulating hormone (alpha-MSH) on rat endotoxin-induced uveitis, and to measure the expression of inflammatory cytokines and chemokines with and without the alpha-MSH treatment over the course of the disease.

METHODS

We injected Lewis rats once with Salmonella typhimurium lipopolysaccharide (LPS) to induce uveitis. The rats were given intravenous injections of 250, 500 or 1000 microg of alpha-MSH. The eyes were examined over the next 24 h for inflammation. Aqueous humor was collected 6, 12 and 24 h after endotoxin injections and the number of infiltrating cells were counted in anterior chamber. In addition, we assayed the concentration of protein, nitric oxide, TNF-alpha, IL-6, MCP-1 and MIP-2.

RESULTS

Rats injected with alpha-MSH showed a significant decrease in the number of infiltrating cells in anterior chamber. Moreover, alpha-MSH-treated rats with endotoxin-induced uveitis (EIU) showed significantly lower concentrations of protein, nitric oxide, proinflammatory cytokines and chemokines in their aqueous humor. Even the early stages of EIU were suppressed by the injection of alpha-MSH.

CONCLUSIONS

Our results demonstrate that the immunosuppressive neuropeptide alpha-MSH inhibits the early induction events of endotoxin-induced inflammation in the eye; therefore, suppresses the subsequent infiltration of cells and intraocular production of inflammatory cytokines and chemokines in eyes. alpha-MSH has a possibility of being a therapeutic strategy for anterior uveitis.

Five new genome types of adenovirus type 37 caused epidemic keratoconjunctivitis in Sapporo, Japan, for more than 10 years

Human adenovirus type 37 (HAdV-37) is a major cause of epidemic keratoconjunctivitis and has recently been the largest causative agent of keratoconjunctivitis in Japan. To investigate the genetic characteristics of HAdV-37 strains isolated in Sapporo, we analyzed the genome types and genetic relationships of 51 strains isolated there from 1990 through 2001. By using DNA restriction analysis, eight genome types (HAdV-37/D1, HAdV-37/D3, and HAdV-37/D6 to HAdV-37/D11) were identified, including five new ones. The restriction fragments of these genome types shared more than 95% identity with those of the prototype strain. By DNA sequence analysis, five and three single nucleotide substitutions, respectively, were found in partial sequences of the hexon and fiber genes. The combinations of mutations resulted in four hexon and fiber types (hx1 to hx4 and f1 to f4) and six hexon/fiber pairs (hx1/f1, hx2/f1, hx1/f2, hx1/f3, hx3/f4, and hx4/f4). The six pairs correlated well with certain genome types. In all three epidemics of keratoconjunctivitis to strike Sapporo in the past 12 years, specific genome types and fiber types were usually isolated: in the first epidemic, HAdV-37/D1 (f1) and HAdV-37/D3 (f1); in the second, HAdV-37/D6 (f2) and HAdV-37/D8 (f3); and in the third, HAdV-37/D10 (f4) and HAdV-37/D11 (f4). We conclude that mutations in the adenovirus genome occurred chronologically and that certain mutations were correlated with the epidemics of adenoviral keratoconjunctivitis.

Effects of fucoxanthin on lipopolysaccharide-induced inflammation in vitro and in vivo

The aim of the present study was to investigate the efficacy of fucoxanthin on endotoxin-induced uveitis (EIU) in rats. The effects of fucoxanthin on endotoxin-induced leucocyte and protein infiltration, nitric oxide (NO), prostaglandin (PG)-E2 and tumour necrosis factor (TNF)-alpha concentrations in rat aqueous humour, as well as on the cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) protein expression in a mouse macrophage cell line (RAW 264.7 cells) were studied. EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). Immediately after the LPS injection, either 0.1, 1 or 10mgkg(-1) of fucoxanthin was injected intravenously. The aqueous humour was collected 24hr later from both eyes, and both the number of cells infiltrating into the aqueous humour and the aqueous humour protein concentration were measured. The levels of PGE2, NO and TNF-alpha were determined by enzyme-linked immunosorbent assay. The RAW 264.7 cells were pretreated with various concentrations of fucoxanthin for 24hr and subsequently incubated with LPS for 24hr. COX-2 and iNOS protein expression was analysed by the Western blotting method. Levels of PGE2, NO and TNF-alpha production were determined. Fucoxanthin suppressed the development of EIU in a dose-dependent fashion. Treatment with fucoxanthin resulted in a reduction in PGE2, NO and TNF-alpha concentrations in the aqueous humour. The expression of COX and iNOS protein in the fucoxanthin treated RAW264.7 cells decreased significantly compared to that the LPS group. It also significantly reduced the concentration of PGE2, NO and TNF-alpha production in the medium of cells. The present result indicate fucoxanthin suppresses the inflammation of EIU by blocking the iNOS and COX-2 protein expression and its anti-inflammatory effect on eye is comparable with the effect of predinisolone used in similar doses.

Anti-inflammatory Effects of Aronia Extract on Rat Endotoxin-Induced Uveitis

PURPOSE

Aronia crude extract (ACE) with high levels of polyphenol compounds has been reported to have antioxidative effects in vitro and in vivo. In this study, attention was focused on the antioxidant effect of ACE. The purpose of the present study was to investigate the effect of ACE on endotoxin-induced uveitis (EIU) in rats. In addition, the endotoxin-induced expression of the inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 proteins was investigated in a mouse macrophage cell line (RAW 264.7) treated with ACE in vitro, to clarify the anti-inflammatory effect.

METHODS

EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). Immediately after the LPS inoculation, 1, 10, or 100 mg ACE or 10 mg prednisolone was injected intravenously. After 24 hours, the aqueous humor was collected from both eyes, and the number of infiltrating cells, protein concentration, nitric oxide (NO), prostaglandin (PG)-E2, and TNF-alpha levels in the aqueous humor were determined. RAW 264.7 cells treated with various concentrations of ACE were incubated with 10 mug/mL LPS for 24 hours. Levels of NO, PGE2, and TNF-alpha were determined by an enzyme-linked immunosorbent assay. The expression of iNOS and COX-2 proteins was analyzed by Western blot analysis.

RESULTS

The number of inflammatory cells, the protein concentrations, and the levels of NO, PGE2, and TNF-alpha in the aqueous humor in the groups treated with ACE were significantly decreased in a dose-dependent manner. In addition, the anti-inflammatory effect of 100 mg ACE was as strong as that of 10 mg prednisolone. The anti-inflammatory action of ACE was stronger than that of either quercetin or anthocyanin administered alone. ACE also suppressed LPS-induced iNOS and COX-2 protein expressions in RAW 264.7 cells in vitro in a dose-dependent manner.

CONCLUSIONS

The results suggest that ACE has a dose-dependent anti-ocular inflammatory effect that is due to the direct blocking of the expression of the iNOS and COX-2 enzymes and leads to the suppression of the production of NO, PGE2, and TNF-alpha.

Peroxisome proliferator-activated receptor gamma ligand prevents the development of chronic pancreatitis through modulating NF-kappaB-dependent proinflammatory cytokine production and pancreatic stellate cell activation

PURPOSE

Thiazolidinedione derivatives (TZDs) are known to be ligands of peroxisome proliferator-activated receptor gamma (PPARgamma). In this study, we investigated the effect of a TZD, troglitazone, on inflammation and fibrogenesis in the pancreas of an experimental model of chronic pancreatitis.

MATERIAL AND METHODS

Male WBN/Kob rats with spontaneous chronic pancreatitis were fed rat chow containing 0.2% troglitazone from 1 to 4 months of age. Immunohistochemical studies of rat pancreas were carried out with monoclonal mouse antibody against human alpha-smooth muscle actin (alpha-SMA) or rabbit polyclonal antibody against collagen type I, collagen type III, or fibronectin. Cytokine production was measured by enzyme-linked immunosorbent assay. The inhibitory action of troglitazone on nuclear factor-kappaB (NF-kappaB) binding activity in activated macrophages was also investigated.

RESULTS

Long-term administration of troglitazone reduced inflammatory cell infiltration and fibrosis in the pancreas of WBN/Kob rats, and expression of alpha-SMA, procollagen I, III, and fibronectin was significantly reduced by troglitazone. The increase in TNF-alpha production by activated macrophages was significantly decreased by troglitazone. Peritoneal macrophages isolated from WBN/Kob rats produced a large amount of TNF-alpha, whereas those from troglitazone-treated WBN/Kob rats produced only a marginal amount of TNF-alpha. Lipopolysaccharide-induced NF-kappaB binding activity in peritoneal macrophages was also significantly reduced by troglitazone.

CONCLUSIONS

Troglitazone prevented the progression of chronic pancreatitis via inhibition of ECM synthesis and proinflammatory cytokine production mediated by the inhibition of NF-kappaB activity.

Expression of maf-B mRNA in the epithelium around the eyelid closure of the mouse eye at embryonic day 18

Maf encodes a transcription factor protein containing a typical basic leucine zipper domain structure, a motif for protein dimerization and DNA binding. We examined the expression of maf-B mRNA in the epithelium around the eyelid closure. Expression of maf-B mRNA was examined in C57Bl6 mice at the embryonic stages in 12.5 days of gestation (E12.5) and E18 using in situ hybridization with 35S-labeled antisense riboprobes. In embryos studied 12.5 days postconception, a message specific for maf-B was not detected around the developing eyelid. In contrast, maf-B was strongly expressed in the epithelium of the eyelid closure at E18. Expression of maf-B was strongly noted in the suprabasal differentiating cells derived from the basal layer of the conjunctiva and epidermis. In contrast, basal cells in the eyelid closure and in the epidermis, as well as keratinizing cells, did not express maf-B. These data indicate that maf-B mRNA is expressed during development of the eyelid closure.

The effects of Ginkgo biloba extract on lipopolysaccharide-induced inflammation in vitro and in vivo

PURPOSE

Ginkgo biloba extract (GBE) contains many different flavone glycosides and terpenoides. Several previous studies have demonstrated that GBE exhibits a wide variety of biological activities, including an antioxidant action, on which we focused our attention. The aim of the present study was to investigate the efficacy of GBE on endotoxin induced uveitis in rats. The anti-inflammatory potency of GBE in vivo was compared with that of prednisolone. In addition, we also investigated nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-alpha (TNF-alpha) and the expression of iNOS in a mouse macrophage cell line (RAW 264.7) treated with GBE in vitro to clarify the anti-inflammatory effect.

METHODS

EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). Immediately after the LPS inoculation, either 1, 10 or 100 microg of GBE were injected intravenously. 24hr later, the aqueous humor was collected from both eyes, and the number of infiltrating cells, protein concentration and NO level in the aqueous humor was determined. The RAW 264.7 cells were pretreated with various concentrations of GBE for 24hr and subsequently incubated with LPS for 24hr. Levels of NO, PGE2 and TNF-alpha were determined by enzyme-linked immunosorbent assay. The expression of iNOS protein was analyzed by Western blotting method.

RESULTS

GBE treatment in vivo decreased the concentrations of protein and NO in the aqueous humor of EIU rats. The anti-inflammatory effect of 1 mg GBE was as strong as that of same dose prednisolone. It also significantly reduced the concentration of PGE2, TNF-alpha and NO production in the medium of RAW 264.7 cells compared to that of the LPS group in vitro. The expression of iNOS protein in the 1000 microg ml(-1) of GBE treated cells decreased significantly.

CONCLUSION

The present results indicate GBE suppresses the inflammation of EIU by blocking the iNOS protein expression and its anti-inflammatory effect on eye is comparable with the effect of prednisolone used in similar doses.

Activation of nuclear factor-kappa B in the conjunctiva with the epithelial scraping of the mouse cornea and human epidemic keratoconjunctivitis

AIM

To examine the expression of p65, one of nuclear factor-kappa B (NF-kappa B), in the conjunctival epithelium of the C57Bl6 mouse and a patient with epidemic keratoconjunctivitis (EKC).

METHODS

Normal and epithelial scraped cornea obtained 6 hours after the injury were processed for paraffin section. Samples of a normal and an EKC conjunctival epithelium were obtained using impression cytology. Both samples were analysed by immunocytochemistry using anti-p65 antibody.

RESULTS

Immunocytochemistry with the anti-NF-kappa B p65 antibody revealed that p65 was localised in the cytoplasm of the conjunctival epithelium in the C57Bl6 mouse without the treatment. Six hours after the scraping of the cornea, p65 protein was expressed in the nuclei of the conjunctival epithelium. p65 was localised in the cytoplasm of the conjunctival epithelium in the human normal eye. p65 protein was expressed in the nuclei of the conjunctival epithelial cells in the EKC patient.

CONCLUSION

These findings suggest that NF-kappa B was activated in the conjunctiva in the epithelial scraping of the mouse cornea and in human EKC.

Involvement of p27KIP1 in the proliferation of the developing corneal endothelium

PURPOSE

To examine the involvement of p27(KIP1) in the regulation of the proliferation of the developing corneal endothelium.

METHODS

Central and peripheral corneas in C57Bl6 mice at postnatal day (P)1, P11, and 12 weeks after birth were analyzed by immunocytochemistry with anti-p27(KIP1), -p57(KIP2), and -proliferating cell nuclear antigen (PCNA) antibodies. Nuclear staining was performed with 4',6'-diamino-2-phenylindole (DAPI) in wholemounts of corneal endothelium of the center and peripheral cornea in wild-type and p27(KIP1) knockout (-/-) mice at 12 weeks of age. p27(KIP1-/-) and control mice were injected with bromodeoxyuridine (BrdU) once on P7, twice per day on P8 and P9, and once on P10 and then were analyzed by a BrdU cell-proliferation assay on P11.

RESULTS

On P1, p27(KIP1) immunoreactivity was detected in a small number of corneal endothelial cells, and many endothelial cells expressed PCNA. At P11 and 12 weeks after birth, p27(KIP1) immunoreactivity was detected in many corneal endothelial cells. PCNA-positive cells in the endothelium were rare on P11 and completely absent at 12 weeks after birth. p57(KIP2) was not detected in either corneal epithelium or endothelium at P1, P11, or 12 weeks after birth. In wholemounts of corneal endothelium at 12 weeks of age, the number of endothelial nuclei in the p27(KIP1-/-) mice was significantly higher than that in wild-type mice in both the center and peripheral regions of the cornea. In the BrdU assay, positive cells were abundant in the corneal endothelium of p27(KIP1-/-) mice, whereas there were few positive cells in control mice. PCNA immunoreactivity in the endothelium of the p27(KIP1-/-) mice was completely absent at 12 weeks after birth.

CONCLUSIONS

These results suggest that p27(KIP1) is involved in the regulation of proliferation in the endothelium of the developing cornea.

[Multiple myxoma in the left ventricle and the left atrium]

Left ventricular myxoma is particulary rare. Our case is a 77-year-old female. Transesophageal echocardiography showed a giant tumor in the left atrium. An urgent operation was performed. A giant mass was excised en bloc via a transinteratrial septal approach. Histopathologically it was myxoma. As a transthoracic echocardiography at 1-year postoperation showed a tumor in the left ventricle. A mass was excised en bloc via a vertical approach. Histopathologically it was diagnosed again as myxoma. We looked at the earliest transesophageal echocardiogram again, and found the small tumor on the same area under the posterior mitral leaflet. At the diagnose of cardiac tumor, possibility of multiple formation should be always considered.

Distribution of p27(KIP1), cyclin D1, and proliferating cell nuclear antigen after retinal detachment

PURPOSE

To examine the expression of the p27(KIP1), cyclin D1, and proliferating cell nuclear antigen (PCNA) in the retina and retinal pigment epithelium (RPE) after retinal detachment.

METHODS

Normal eyes and eyes at 2 or 4 days after retinal detachment with the C57B16 mouse were analyzed by immunocytochemistry using anti-p27(KIP1), anti-cyclin D1, and anti-proliferating cell nuclear antigen (PCNA) antibodies as well as anti-glutamate synthetase (GS) antibody.

RESULTS

The p27(KIP1) positive nuclei were distributed in the inner nuclear layer (INL) and the RPE of the normal mice eye. In the INL, p27(KIP1) was detected in the middle sublayer, where the nuclei of glutamate synthetase positive Müller cells were situated. In contrast, cyclin D1 was not detected either in the retina or in the RPE. At 2 and 4 days after the retinal detachment, RPE cells under the detached retina were negative for p27(KIP1) and positive for cyclin D1 and PCNA. In the INL of the detached retina, p27(KIP1) was detected after 2 days, but was not detected after 4 days. In contrast, PCNA was not detected in the INL after 2 days, but was detected after 4 days. Cyclin D1 was detected in the middle sublayer of the INL at both 2 and 4 days after the retinal detachment.

CONCLUSION

These results suggested that degradation of p27(KIP1) and expression of cyclin D1 was involved in the proliferation of the Müller cells as well as RPE cells after retinal detachment.

Involvement of p27(KIP1) in proliferation of the retinal pigment epithelium and ciliary body

According to observations in various cell lines, elimination of the cyclin-dependent kinase inhibitor p27(KIP1) during the late G1 phase of the cell cycle is required for progression to the S phase. Eyes from C57BL/6 mice at embryonic days 13, 14, and 18, and at 4 weeks of age, were analyzed by a bromodeoxyuridine cell proliferation assay and by immunocytochemistry using anti-p27(KIP1) antibody. On embryonic days 14 and 18, p27(KIP1) was detected in the ciliary body. This protein also was detected in the nuclei of the many cells of the retinal pigment epithelium on embryonic day 18, and was present in all such cells at 4 weeks of age. When p27(KIP1)-/- knockout and control mice were injected with bromodeoxyuridine between postnatal days 7 and 10 and analyzed on day 11, positive cells were abundant in the retinal pigment epithelium and the ciliary body of p27(KIP1)-/- mice, whereas few cells were positive in control mice. By fluorescent nuclear staining in whole mounts of retinal pigment epithelium at 12 weeks of age, more nuclei were present in p27(KIP1)-/- than in the wild-type mice. These results suggest that p27(KIP1) was involved in regulation of proliferation in the RPE and the ciliary body.

Inhibition of endotoxin-induced uveitis and potentiation of cyclooxygenase-2 protein expression by alpha-melanocyte-stimulating hormone

PURPOSE

The efficacy of alpha-melanocyte-stimulating hormone (alpha-MSH) on endotoxin-induced uveitis (EIU) was investigated in rats. Several studies have demonstrated that there are various inflammatory reactions mediated by an alpha-MSH receptor in macrophages. In addition, as it is known that cyclooxygenase (COX)-2 is induced by a variety of stimuli and plays an important role in inflammation, COX-2 expression was also investigated in macrophage cells treated with alpha-MSH in vitro to clarify its anti-inflammatory effect.

METHODS

EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). The number of infiltrating cells and protein concentration in the aqueous humor collected 24 hours after the LPS treatment was determined. The levels of prostaglandin (PG)-E2, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1 production were determined. RAW 264.7 cells were pretreated with various concentrations of alpha-MSH for 24 hours and subsequently incubated with 10 microg/mL LPS for 24 hours. COX-2 protein expression was analyzed by Western blot analysis.

RESULTS

alpha-MSH suppressed the development of EIU in a dose-dependent fashion. The treatment with alpha-MSH reduced the PGE2, TNF-alpha, IL-6, and MCP-1 concentrations in aqueous humor. The COX-2 protein expression in the alpha-MSH group decreased.

CONCLUSIONS

This study suggests that alpha-MSH has an antiocular inflammatory effect, by suppression of PGE2, TNF-alpha, IL-6, and MCP-1 production and blocking of COX-2 expression.

Effect of human cationic antimicrobial protein 18 Peptide on endotoxin-induced uveitis in rats

PURPOSE

Human cationic antimicrobial protein 18 (hCAP18, 18 kDa) was originally identified in leukocytes on the basis of its antimicrobial activity. The peptide composed of the 27 C-terminal amino acids of hCAP18 (hCAP18(109-135)) binds lipopolysaccharide (LPS). The purpose of the present study was to investigate the effects of hCAP18 peptide on endotoxin-induced uveitis (EIU) in rats.

METHODS

EIU was induced by footpad injection of LPS. Each rat was injected intravenously with 1, 10, or 100 micro g hCAP18 peptide in 0.1 mL of PBS immediately after LPS injection in male Lewis rats. At 24 hours after LPS injection, enzyme-linked immunosorbent assay was performed to evaluate concentrations of protein, nitric oxide (NO), tumor necrosis factor (TNF)-alpha, prostaglandin (PG)-E2, interleukin (IL)-6, monocyte chemoattractant protein (MCP)-1 and macrophage inflammatory protein (MIP)-2 in aqueous humor. Also, EIU was evaluated by counting inflammatory cells in aqueous humor.

RESULTS

hCAP18 peptide at 10 and 100 micro g significantly suppressed an LPS-induced increase in the number of inflammatory cells and the levels of protein, NO, TNF-alpha, PGE2, MCP-1, and MIP-2. The anti-inflammatory effect of 10 micro g hCAP18 peptide was as strong as that of 100 micro g hCAP18 peptide. Treatment with 1 micro g hCAP18 peptide did not suppress EIU, compared with the LPS group.

CONCLUSIONS

The present results indicate that hCAP18 peptide suppresses development of EIU. A possible mechanism for the ocular anti-inflammatory effect of hCAP18 peptide is that it suppresses onset of LPS-triggered inflammatory reactions by binding directly to LPS.

Auricular chondritis in young ear-tagged Crj:CD(SD)IGS rats

Gross and histopathological features of auricular chondritis in young Crj:CD(SD)IGS rats were examined. Although the rats were identified with metallic ear tags on the right pinnae, auricular chondritis was also observed on the contralateral (left) ear in some animals. Histopathologically, the lesions were characterized by granulomatous inflammation with destruction of the normal cartilaginous plate, formation of new cartilaginous nodules and osseous metaplasia. Proliferative cell nuclear antigen (PCNA) positive cells were present predominantly in chondrocytes found in the centre of the newly-formed cartilaginous nodules. The results suggest that the newly-formed cartilaginous nodules were due to interstitial proliferation of chondrocytes.