Allithiamine Exerts Therapeutic Effects on Sepsis by Modulating Metabolic Flux during Dendritic Cell Activation

Recent studies have highlighted that early enhancement of the glycolytic pathway is a mode of maintaining the pro-inflammatory status of immune cells. Thiamine, a well-known co-activator of pyruvate dehydrogenase complex, a gatekeeping enzyme, shifts energy utilization of glucose from glycolysis to oxidative phosphorylation. Thus, we hypothesized that thiamine may modulate inflammation by alleviating metabolic shifts during immune cell activation. First, using allithiamine, which showed the most potent anti-inflammatory capacity among thiamine derivatives, we confirmed the inhibitory effects of allithiamine on the lipopolysaccharide (LPS)-induced pro-inflammatory cytokine production and maturation process in dendritic cells. We applied the LPS-induced sepsis model to examine whether allithiamine has a protective role in hyper-inflammatory status. We observed that allithiamine attenuated tissue damage and organ dysfunction during endotoxemia, even when the treatment was given after the early cytokine release. We assessed the changes in glucose metabolites during LPS-induced dendritic cell activation and found that allithiamine significantly inhibited glucose-driven citrate accumulation. We then examined the clinical implication of regulating metabolites during sepsis by performing a tail bleeding assay upon allithiamine treatment, which expands its capacity to hamper the coagulation process. Finally, we confirmed that the role of allithiamine in metabolic regulation is critical in exerting anti-inflammatory action by demonstrating its inhibitory effect upon mitochondrial citrate transporter activity. In conclusion, thiamine could be used as an alternative approach for controlling the immune response in patients with sepsis.     

Up-regulation of skeletal muscle LIM protein 1 gene by 25-hydroxycholesterol may mediate morphological changes of rat aortic smooth muscle cells

Changes in the expression level of the skeletal muscle LIM protein 1 (SLIM1) in cultured A10 cells were monitored in response to 25-hydroxycholesterol (25-HC), an oxidized form of cholesterol present in the oxidized low-density lipoproteins. The level of SLIM1 mRNA was elevated in a time- and concentration-dependent manner by treatment of 25-HC. Expressions of smooth muscle (SM) alpha-actin and calponin-1 (CNN-1), early markers for SMC differentiation, were also increased by the 25-HC treatments. Expressions of all three genes (SLIM1, SM alpha-actin and CNN-1) were simultaneously elevated in the cells treated with 9-cis retinoic acid (RA). On the other hand, the SLIM1 expression induced by the 25-HC or 9-cis RA (as well as SM alpha-actin and CNN-1) was decreased by the treatment of 15d-PGJ2. Since the 25-HC, 9-cis RA and 15d-PGJ2 were ligands for the LXR, RXRalpha and PPARgamma respectively, there might be a functional positive cross-talk between LXR and RXRalpha pathways and a negative cross-talk between PPARgamma and LXR and/or RXRalpha pathways in the regulation of SLIM1 expression. The cells stably transfected with the expressional vector for SLIM1 also showed an elevation in the levels of SM alpha-actin and CNN-1. In addition, an over-production of SLIM1 in the cells resulted in a change in the cell-shape into a spindle-like form, which is identical to that observed after a prolonged treatment of the cells with cholesterol.     

Optimization of antibacterial activity by Gold-Thread (Coptidis Rhizoma Franch) against Streptococcus mutans using evolutionary operation-factorial design technique

This study was conducted to find the optimum extraction condition of Gold-Thread for antibacterial activity against Streptococcus mutans using The evolutionary operation-factorial design technique. Higher antibacterial activity was achieved in a higher extraction temperature (R2 = -0.79) and in a longer extraction time (R2 = -0.71). Antibacterial activity was not affected by differentiation of the ethanol concentration in the extraction solvent (R2 = -0.12). The maximum antibacterial activity of clove against S. mutans determined by the EVOP-factorial technique was obtained at 80 degrees C extraction temperature, 26 h extraction time, and 50% ethanol concentration. The population of S. mutans decreased from 6.110 logCFU/ml in the initial set to 4.125 logCFU/ml in the third set.     

Mouse strain-dependent osteoclastogenesis in response to lipopolysaccharide

Bacterial lipopolysaccharide (LPS) is a potent stimulator of bone resorption in periodontitis. Co-culture systems of mouse calvaria-derived osteoblasts and bone marrow-derived preosteoclasts were used as an in vitro osteoclast differentiation. This study revealed that co-cultures using ddY or ICR mouse strain responded differently to LPS while responded equally to 1alpha,25(OH)2D3. Thus, the different response to LPS indicates dissimilarity of two mouse stains in their capacity for generating osteoclasts while the two mouse strains share the similarity in response to 1alpha,25(OH)2D3. To identify which cells between osteoblasts and preosteoclasts in the co-culture are responsible for the dissimilarity, the reciprocal co-cultures were performed between ddY and ICR mouse strains. The treatment of 1,25(OH)2D3 to ddY/ICR (osteoblasts from ddY/preosteoclasts from ICR) and ICR/ddY reciprocal co-cultures also showed the similarity. In case of LPS treatment, the results of ddY/ICR were similar to ddY/ddY and the results of the other reciprocal co-culture, ICR/ddY combination, were consistent with those of ICR/ICR. It suggests that the dissimilarity between the two mouse strains may resident in osteoblasts but not in preosteoclasts. Therefore, the osteoblast is responsible for mouse strain-dependent osteoclastogenesis in response to LPS. Although mouse models will continue to provide insights into molecular mechanisms of osteoclastogenesis, caution should be exercised when using different mouse strains, especially ddY and ICR strains as models for osteoclast differentiation.     

Effect of maternal restraint stress on fetal development of ICR mice.

The present study was conducted to elucidate the susceptibility of embryos and fetuses at different gestational stages to the maternal stress in mice. Groups of pregnant ICR mice were subjected to daily 12-h restraint stress, taped in the supine position on a plastic board, on gestational days (GD) 1-4, 5-8, 9-12 and 13-16, respectively. Caesarean sections were performed on gestational day 18, and the fetuses were weighed and examined for morphological defects. During the daily restraint for 4 days, the maternal body weights markedly decreased. Although the body weights recovered gradually after termination of the stress, the recovery was not full until the final stage of pregnancy. Interestingly, restraint stress caused growth retardation of the fetuses, leading to a significant decrease in their body weights, and increased early and late resorptions of embryos and fetuses according to the stress periods. Although the preceding (GD1-4) and concurrent (GD5-8) stresses did not affect embryonic implantation, restraint stress on GD9-12 caused cleft palate. Whereas vertebral abnormalities, mainly bipartite ossification, were observed only in animals stressed on GD5-8, abnormalities of sternebrae, exhibiting asymmetric or bipartite ossification, were enhanced by the stress at all of the gestational stages. On the other hand, the incidence of other malformations including renal malposition and costal abnormalities was not increased by stress at any of the 4 stages. Taken together, the results suggest that intensive restraint stress influences the maternal body weight resulting in growth retardation and increased mortality of embryos and fetuses, in addition to gestational stage-specific ventricular dilatation, cleft palate and sternal abnormalities.     

Alkaloid accumulation in Catharanthus roseus cell suspension cultures fed with stemmadenine

Feeding stemmadenine to Catharanthus roseus cell suspension culture resulted in the accumulation of catharanthine, tabersonine and condylocarpine. Condylocarpine is not an intermediate in the pathway to catharanthine or tabersonine when it is fed to the cultures. The results support the hypothesis that stemmadenine is an intermediate in the pathway to catharanthine and tabersonine.