Alpha-lipoic acid protects human dopaminergic neuronal cells against hydrogen peroxide-induced cell injury by inhibiting autophagy and apoptosis

Alpha-lipoic acid (ALA) is a naturally occurring antioxidant and has been previously used to treat diabetes and cardiovascular disease. However, the autophagy effects of ALA against oxidative stress-induced dopaminergic neuronal cell injury remain unclear. The aim of this study was to investigate the role of ALA in autophagy and apoptosis against oxidative stress in the SH-SY5Y human dopaminergic neuronal cell line. We examined SH-SY5Y phenotypes using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay (cell viability/proliferation), 4′,6-diamidino-2-phenylindole dihydrochloride nuclear staining, Live/Dead cell assay, cellular reactive oxygen species (ROS) assay, immunoblotting, and immunocytochemistry. Our data showed ALA attenuated hydrogen peroxide (H2O2)-induced ROS generation and cell death. ALA effectively suppressed Bax up-regulation and Bcl-2 and BclxL down-regulation. Furthermore, ALA increased the expression of the antioxidant enzyme, heme oxygenase-1. Moreover, the expression of Beclin-1 and LC-3 autophagy biomarkers was decreased by ALA in our cell model. Combined, these data suggest ALA protects human dopaminergic neuronal cells against H2O2-induced cell injury by inhibiting autophagy and apoptosis.

Alpha-lipoic acid protects human dopaminergic neuronal cells against hydrogen peroxide-induced cell injury by inhibiting autophagy and apoptosis

Alpha-lipoic acid (ALA) is a naturally occurring antioxidant and has been previously used to treat diabetes and cardiovascular disease. However, the autophagy effects of ALA against oxidative stress-induced dopaminergic neuronal cell injury remain unclear. The aim of this study was to investigate the role of ALA in autophagy and apoptosis against oxidative stress in the SH-SY5Y human dopaminergic neuronal cell line. We examined SH-SY5Y phenotypes using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay (cell viability/proliferation), 4′,6-diamidino-2-phenylindole dihydrochloride nuclear staining, Live/Dead cell assay, cellular reactive oxygen species (ROS) assay, immunoblotting, and immunocytochemistry. Our data showed ALA attenuated hydrogen peroxide (H2O2)-induced ROS generation and cell death. ALA effectively suppressed Bax up-regulation and Bcl-2 and BclxL down-regulation. Furthermore, ALA increased the expression of the antioxidant enzyme, heme oxygenase-1. Moreover, the expression of Beclin-1 and LC-3 autophagy biomarkers was decreased by ALA in our cell model. Combined, these data suggest ALA protects human dopaminergic neuronal cells against H2O2-induced cell injury by inhibiting autophagy and apoptosis.

Histological assessment of the palatal mucosa and greater palatine artery with reference to subepithelial connective tissue grafting / 대한해부학회지

This study aimed to measure the thickness of the epithelium and lamina propria of the palatal mucosa and to elucidate the location of the greater palatine artery to provide the anatomical basis for subepithelial connective tissue grafting. Thirty-two maxillary specimens, taken from the canine distal area to the first molar distal area, were embedded in paraffin and stained with hematoxylin-eosin. The thickness of the epithelium and lamina propria of the palatal mucosa was measured at three positions on these specimens, starting from 3 mm below the alveolar crest and in 3-mm intervals. The location of the greater palatine artery was evaluated by using image-processing software. The mean epithelial thickness decreased significantly in the posterior teeth; it was 0.41, 0.36, 0.32, and 0.30 mm in the canine, first premolar, second premolar, and first molar distal areas, respectively. The lamina propria was significantly thicker in the canine distal; it was 1.36, 1.08, 1.09, and 1.05 mm, respectively. The mean length from the alveolar crest to the greater palatine artery increased toward the posterior molar; it was 7.76, 9.21, 10.93, and 11.28 mm, respectively. The mean depth from the surface of the palatal mucosa to the greater palatine artery decreased from the canine distal to the first premolar distal but increased again toward the posterior molar; it was 3.97, 3.09, 3.58, and 5.50 mm, respectively. Detailed histological assessments of the lamina propria of the palatal mucosa and the greater palatine artery are expected to provide useful anatomical guidelines for subepithelial connective tissue grafting.

Morphometric Analysis of the Supraorbital and Infraorbital Foramina Based on the Medial Canthus in Koreans / 체질인류학회지

Knowledge of the location of the maxillo-facial foramina is essential for regional nerve blocks and endoscopic surgical procedures to avoid nerve injury passing through these foramina. The purposes of this study were to determine the locations of the supraorbital foramen (SOF) and the infraorbital foramen (IOF) related to medial canthus (MC), and to analyze the morphology of these foramina. Thirty-two embalmed cadavers (64 sides, mean age: 64.1 years) and 33 dry skulls (66 sides) were used. The distances from the SOF, IOF, and MC to facial midline were directly measured on the cadavers using digital Vernier caliper. The vertical and horizontal distances of the SOF and IOF relative to the medial canthus were indirectly measured on the digital photographs using image analyzer software. The vertical and horizontal diameters of the IOF, and its location in relation to maxillary tooth were evaluated on the dry skull. Statistical analysis was performed using one-way ANOVA with declaration of significant difference when P<0.05. The mean distances of SOF, MC, and IOF to the facial midline were 24.13 mm, 15.00 mm, and 29.11 mm, respectively. The SOF was located 18.99 mm superior and 9.05 mm lateral to the medial canthus. The distance between the medial canthus and the SOF was 22.67 mm, and the vertical angle (Angle 1) between these structures was 24.36degrees superolaterally. The IOF was located 26.69 mm inferior and 13.53 mm lateral to the medial canthus. The distance between the medial canthus and IOF was 30.82 mm and the vertical angle (Angle 2) between these structures was 26.59degrees inferolaterally. In the this study, spraorbital notch (SON) was found more frequently than the SOF. The mean vertical and horizontal diameters of IOF were 3.36 mm, 3.45 mm, respectively. IOF was most commonly found in the same vertical plane with the second upper premolar. In conclusion, these results are important for performing local anesthetic, facial plastic surgery, and other invasive procedures in the forehead and periorbital region to prevent injury of neurovascular bundles passing through these foramina.

Effects of Melatonin on MDPC-23 Cells Differentiation / 체질인류학회지

Melatonin is the major hormone released from the pineal gland and regulates a variety of physiological and pathophysiological processes. According to the recent studies the melatonin plays an important role in regulation of bone growth. The purpose of this study was to determine whether melatonin promotes the cell differentiation and nodules formation in MDPC-23 pre-odontoblast cell line. MDPC-23 cells were cultured for up to 15 days in growth media containing differentiation medium with melatonin or without melatonin. Cultures were stained with Alizarin-S. The expression of the mRNAs for DSPP, OC, ALP and NFI-C were analyzed by RT-PCR. The results were as follows. Cultures containing melatonin at day 15 showed extensive mineralization as compared with control cultures. Melatonin increased the expression of DSPP and OC mRNAs in MDPC-23 cells in a concentration-dependent manner. However, melatonin did not changed ALP expression. Melatonin markedly decreased mRNA expression of NFI-C in early stage cultures as compared with control cultures. These results demonstrated that melatonin is capable of promoting MDPC-23 cells differentiation and mineralization and suggested that melatonin may play an important role in dentin formation.

Effect of NFI-C on the Expression of Smad and TGF-betaR1 / 대한해부학회지

NFI-C null mice demonstrate aberrant odontoblast differentiation and abnormal dentin formation, and thus develop molars lacking roots. However, other tissues and organs in the body including ameloblasts appear to be unaffected. Abnormal dentin in NFI-C null mice shares morphological similarities to the osteodentin that is formed in dental caries. However, little is known about the relationship between NFI-C and osteodentin formation. In this study, to elucidate the molecular characteristics of abnormal odontoblast in NFI-C null mice, we examined the levels of Ask-1, Cdc-2, Smad2/3, and TGF-betaR1 in cell culture and tissue sections from NFI-C null mice using immunofluorescence and immunohistochemistry. NFI-C protein was localized in the nucleus and cytoplasm of normal odontoblasts in vitro. Ask-1 and Cdc-2 proteins were shown in the perinuclear cytoplasm of both normal and NFI-C null mice. There were no differences in the pattern of production of Ask-1 and Cdc-2 proteins between normal and NFI-C null mice. Smad2/3 was not found in the odontoblast and subodontoblastic cells of the normal mice, whereas NFI-C null mice showed Smad2/3 immunoreactivity in the odontoblasts and subodontoblastic cells of the tooth pulp. TGF-betaR1 was weakly immunopositive in the odontoblast and subodontoblastic cells of normal mice, whereas it was detected strongly in the subodontoblastic cells of the NFI-C null mice. These results suggest that disruption of NFI-C increased the expression of Smad2/3 and TGF-betaR1 in developing odontoblasts and consequently caused abnormal dentin formation, similar to osteodentin.