2007, Vol.20, No.2

Anatomy & Biological Anthropology 2023 KCI Impact Factor : 0.33

pISSN : 2671-5651 / eISSN : 2671-566X
https://journal.kci.go.kr/aba

Molecular mechanism of nuclear factor-κB(NF-κB) in the atherosclerosis has been unclear. Recently, NF-κB activating function of tissue transglutaminase (tTGase), multifunctional calcium-dependent transamidation enzyme, have been reported in the various tissues like neuroglia. In this report, we investigated the immunoreactivity of tTGase at the human atherosclerotic coronary artery, and examined the effect of tTGase on the well-known proatherogenic NF-κB pathway using tTGase-overexpressed cells. Immunohistochemical studies on autopsy samples showed that immunoreactivity of tTGase was markedly elevated in the neointimal tissues of atherosclerotic coronary arteries with progression of disease. Immunohistochemical staining also demonstrated that phosphorylated I-κB was activated in the atherosclerotic vessel wall. In vitro study using rat cardiomyoblast (H9c2) and tTGase-overexpressed H9c2 showed that activated tTGase enhanced the phosphorylation of I-κB, and this activation was inhibited by tTGase specific inhibitors. These findings suggest that cytosolic tTGase may serve as an activator of NF-κB.

This study was performed to investigate the changes of immunoreactivities of calcium channel α1B subunit in myenteric plexus of capsaicin treated adult rats. Sprague Dawley rats (about 200 g) were injected with capsaicin (50 mg/kg) subcutaneously. Ileal myenteric plexus was prepared by whole mount preparation method in 1 day, 2 days, 1 week and 4 weeks after capsaicin treated adult rats. Each myenteric plexus was reacted with NADH-TR and immunostained with α1B subunit. Myenteric ganglion cell numbers were counted by image analyzer. In control group myenteric plexus was arranged in rectangular appearance; myenteric ganglia and internodal strand were immunoreacted with α1B subunit. Immunoreactive cells were 56.0% of total myenteric neurons. Total numbers of immunoreactive cells decreased by 19.0%, 37.9% and 64.9% in 1 day, 2 days, and 1 week after capsaicn treated group respectively. In 4 weeks after capsaicin treated group, immunoreactivities of α1B subunit were increased compared to that of the 1 week after group. However total numbers of immuoreactive cells decreased by 43.9% compared to that of the control group. In conclusion, we confirmed that immunoreactivities of α1B subunit were decreased until 1 week after capsaicin treatment and recovered progressively after that time. It will take more than 4 weeks latency to recover the control immunoreactivities of α1B subunit.

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.