Cis-urocanic acid suppresses UV-B-induced interleukin-6 and -8 secretion and cytotoxicity in human corneal and conjunctival epithelial cells in vitro.

PURPOSE: Urocanic acid (UCA) is a major ultraviolet (UV)-absorbing endogenous chromophore in the epidermis and is also an efficacious immunosuppressant. The anti-inflammatory and cytoprotective effects of cis-UCA were studied in ocular surface cell cultures exposed to UV-B irradiation. METHODS: Human corneal epithelial cells (HCE-2) and human conjunctival epithelial cells (HCECs) were incubated with 10, 100, 1,000, and 5,000 microg/ml cis-UCA with and without a single UV-B irradiation dose. The concentrations of IL-1beta, IL-6, IL-8, and TNF-alpha in the culture medium and caspase-3 activity in the cell extract sampled were measured by enzyme-linked immunosorbent assay (ELISA). Cell viability was measured by the colorimetric MTT (3-(4,5-dimethyldiazol- 2-yl)-2,5-diphenyltetrazolium bromide) assay. RESULTS: UV-B irradiation multiplied interleukin IL-6 and IL-8 secretion levels in HCE-2 cells and HCECs as analyzed with ELISA. Cell viability as measured by the MTT assay declined by 30%-50% in HCE-2 cells and by 20%-40% in HCECs after UV-B irradiation. Moreover, UV-B increased caspase-3 activity in both cell types as analyzed with ELISA. Treatment with 100 microg/ml cis-UCA completely suppressed IL-6 and IL-8 secretion, decreased caspase-3 activity, and improved cell viability against UV-B irradiation. No significant effects on IL-6 or IL-8 secretion, caspase-3 activity, or viability of the non-irradiated cells were observed with 100 microg/ml cis-UCA in both cell types. The 5,000 microg/ml concentration was toxic. CONCLUSIONS: These findings indicate that cis-UCA may represent a promising anti-inflammatory and cytoprotective treatment option to suppress UV-B-induced inflammation and cellular damage in human corneal and conjunctival epithelial cells.

The effect of glycaemic control on the quantitative characteristics of retinopathy lesions in patients with type 2 diabetes mellitus: 10-year follow-up study.

BACKGROUND: Diabetic retinopathy (DR) represents a common complication of type 2 diabetes mellitus. Appearance of DR lesions such as microaneurysms, haemorrhages, hard and soft exudates, IRMA and neovascularisation reflect the severity of DR. The aim of our study was to investigate the association of selected glycaemic parameters with particular DR abnormalities and their characteristics in patients with type 2 diabetes. METHODS: Eighty-three middle-aged patients with newly diagnosed type 2 diabetes mellitus participated in this 10-year prospective study. The glycaemic parameters such as glycated haemoglobin A1c (HbA1c), fasting blood/plasma glucose as well as 1- and 2-hour post-load glucose values were recorded at baseline, 5-year and 10-year follow-up. The fundus photographs were taken at baseline and then at 5-year and 10-year follow-ups and used for quantitative evaluation. RESULTS: Statistically significant positive correlations were found between all investigated 5-year glucose values and the extent of DR lesions at 10-year follow-up (p < 0.003). The 1- and 2-hour post-load glucose values correlated with the DR lesions with the highest significance (p

Juvenile-onset neuronal ceroid lipofuscinosis with infantile CLN1 mutation and palmitoyl-protein thioesterase deficiency.

Accurate diagnosis, especially in progressive hereditary diseases, is essential for the treatment and genetic counseling of the patient and the family. Neuronal ceroid lipofuscinoses (NCL) are amongst the most common groups of neurodegenerative diseases. Infantile, juvenile, and adult-onset types with multiple genotype-phenotype associations have been described. A fluorimetric enzyme assay for palmitoyl protein thioesterase (PPT) from leukocytes and fibroblasts has been previously developed to confirm the diagnosis of infantile NCL. We describe a patient with juvenile-onset NCL phenotype with a new CLN1 mutation and deficient PPT activity. Over 40 different mutations have been found in patients with PPT deficiency, indicating that screening for known mutations is not an efficient way to diagnose this disorder. Therefore, PPT enzyme analysis should precede mutation analysis in suspected PPT deficiency, particularly in patients with granular osmiophilic deposits (GROD) or in patients who have negative ultrastructural data. The use of enzyme assay led to the diagnosis of this patient with juvenile-onset Finnish variant NCL with PPT deficiency, and we expect that greater awareness of the utility of the enzymatic assay may lead to identification of other similar cases awaiting a definitive diagnosis.