Minocycline and sulforaphane inhibited lipopolysaccharide-mediated retinal microglial activation

PURPOSE: To elucidate the inhibitory effect of minocycline and sulforaphane on lipopolysaccharide (LPS)-induced retinal microglial activation and the mechanisms through which they exerted their inhibitory effects. METHODS: Primary retinal microglial cultures were exposed to LPS with or without minocycline and sulforaphane. The mRNA expression of monocyte chemotactic protein (MCP)-1, MCP-3, macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, eotaxin, regulated upon activation normal T-cell expressed and secreted (RANTES) protein, and interleukin (IL)-10 were examined by reverse transcription polymerase chain reaction (RT-PCR) assay. The mRNA expression of inducible nitric oxide synthase (iNOS) and subsequent nitric oxide (NO) production were examined by RT-PCR assay and Griess reagent assay. Protein expression of the p65 subunit of nuclear factor-kappa B (NF-kappa B) and p-p38, p-p44/42 and p-JNK mitogen-activated protein kinases (MAPKs) were examined by Western blot and immunofluorescent analysis. RESULTS: Cultured retinal microglial cells were activated following exposure to LPS. The mRNA expression and protein production of eotaxin, RANTES, and IL-10 and the mRNA expression of iNOS and subsequent NO production were upregulated. The protein expression of p-p38, p-JNK, and the p65 subunit of NF-kappa B were also upregulated. However, the protein expression of p-p44/42 was not significantly changed. Pretreatment with minocycline or sulforaphane for 1 h before LPS administration inhibited LPS-induced microglial morphological change and inhibited LPS-induced upregulation of p-p38, but had no effect on the expression of p-p44/42, p-JNK, and the p65 subunit of NF-kappa B. CONCLUSIONS: Minocycline and sulforaphane inhibited LPS-induced retinal microglial activation, Western blot and immunofluorescent studies showed decreased p-p38 MAPK expression. We suggested that the inhibitory effect of minocycline and sulforaphane was partly through a p38 MAPK-dependent mechanism.Biochemistry & Molecular BiologyOphthalmologySCI(E)PubMed18ARTICLE117-181083-10931

Pathologic study of early manifestations of polypoidal choroidal vasculopathy and pathogenesis of choroidal neo-vascularization

Purpose: To describe the histopathologic features of an early case of presumably bilateral polypoidal choroidal vasculopathy (PCV) in two eyes obtained at autopsy from a patient with no prior ocular therapy. Observations: The choroid of both eyes at the macular and peripapillary regions was greatly thickened with dilated, thin walled choroidal venules intertwining with arteriosclerotic arterioles in the Sattler's layer of the choroidal vasculature. At the temporal and nasal equatorial regions of both eyes many of these congested venular channels abruptly disappeared and were replaced by loose connective tissue with loss of the normal choroidal stromal tissue and uveal melanocytes. A few remaining venules showed intraluminal sloughing of endothelial cells and deposition of fibrinous material networks suggesting occlusion of these choroidal venules. At this equatorial location, serous detachment of retinal pigment epithelium (RPE) appeared and a thin neovascular membrane with cords of endothelial cell invaded into the sub-RPE space. Anteriorly, the neovascular membrane expanded and bulged into the sub-retinal space with dilated neovascular capillaries in a “grape like” or polypoidal configuration. Conclusion and importance: Polypoidal Choroidal Vasculopathy is a disease of the dilated and multi-layered choroidal venules. Occlusion of these choroidal vascular channels might give rise to choroidal stasis and ischemia leading to serous RPE detachment and a sub-RPE neovascular membrane. Gross dilatation of the choroidal venules and capillaries in the sub-RPE neovascular membrane leads to the characteristic “grape like” structures, a unique clinical feature in this disease entity. These pathologic features of PCV are different from the pathologic changes of neovascular age-related macular degeneration (nAMD). Consequently, PCV and nAMD are two distinct diseases. However, in the late stage of both entities, choroidal ischemia in both diseases, lead to sub-RPE neovascularization and subsequent sub-RPE and/or sub-retinal hemorrhage. These results in both entities showed comparable clinical and pathologic features that are frequently mistaken PCV as a sub-type of Neovascular AMD. Keywords: Polypoidal choroidal vasculopathy, Neovascular age-related macular degeneration, Choroidal venule, Choroidal neo-vascularization, Venous stasis choroidopath

Western blot analysis of NF-κB P65 protein levels in control and retinas for each age group

Little expression of NF-κB P65 (bands at 65 kDa) was found in the control retinas at different age groups. NF-κB P65 protein was detected in the samples from retinas. GAPDH (35 kDa) was used as a loading control. Intensitometry of immunoreactive bands in retinas. Note the protein levels of NF-κB P65 in retinas were significantly increased at P10 and reached a peak at P12. It kept a high level up to P18 and was markedly reduced by P28 (*p<p><b>Copyright information:</b></p><p>Taken from "κB "</p><p></p><p>Molecular Vision 2008;14():1075-1080.</p><p>Published online 10 Jun 2008</p><p>PMCID:PMC2426720.</p><p></p