• Archives of Pharmacal Research
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• v.26 no.7
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• pp.559-563
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• 2003

Cytokines produced by immune cells infiltrating pancreatic islets have been incriminated as important mediators of $\beta$-cell destruction in insulin-dependent diabetes mellitus. In non insulin-dependent diabetes, cytokines are also associated with impaired $\beta$-cell function in high glucose condition. By the screening of various natural products blocking $\beta$-cell destruction, we have recently found that epigallocatechin gallate (EGCG) can prevent the in vitro destruction of RINm5F cell, an insulinoma cell line, that is induced by cytokines. In that study we suggested that EGCG could prevent cytokine-induced $\beta$-cell destruction by down-regulation of nitric oxide synthase (NOS) through inhibition of NF-kB activation. Here, to verify the in vivo antidiabetogenic effect of EGCG, we examined the possibility that EGCG could also prevent the experimental autoimmune diabetes induced by the treatment of multiple low doses of streptozotocin (MLD-STZ), which is recognized as an inducer of type I autoimmune diabetes. Administration of EGCG (100 mg/day/kg for 10 days) during the MLD-STZ induction of diabetes reduced the increase of blood glucose levels caused by MLD-STZ. Ex vivo analysis of $\beta$-islets showed that EGCG downregulates the MLD-STZ-induced expression of inducible NOS (iNOS). In addition, morphological examination showed that EGCG treatment ameliorated the decrease of islet mass induced by MLD-STZ. In combination these results suggest that EGCG could prevent the onset of MLD-STZ-induced diabetes by protecting pancreatic islets. Our results therefore revealed the possible therapeutic value of EGCG for the prevention of diabetes mellitus progression.

• Journal of Pharmaceutical Investigation
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• v.41 no.1
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• pp.19-24
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• 2011

In order to enhance the clinical efficacy of 5-aminolevulinic acid-induced photodynamic therapy (ALA-PDT), liposomal formulations using bulk hydrogenated phospholipids from soybean were introduced. Three types of lipids, S75-3, S100-3, and SL80-3 were used for formulating ALA. The pH of all the liposomal ALA is 4.5~5.5 and the size is 50~200 nm. All the liposomal formulations gave better ex vivo ALA skin penetration using nude mice skin in Franz cell than free ALA did. Among them, SL80-3 including 22% of lyso-phosphocholine achieved excellent ALA penetration when compared with those of S75-3 and S100-3 which have only 1~2% of lyso-phospholipids. S100-3 showed a little better results than S75-3 did. Addition of humectants (glycerine, propylene glycol, butylene glycol, betaine) in liposomal ALA formulated with SL80-3 produced little enhancing effect in ALA penetration. On the other hand, addition of surfactants (Tween 20, 60, Brij 72, 76, 78) in same liposomal system produced significant increase in ALA penetration. Among them, transferosomal system of lyso-phospholipid, SL80-3 and the surfactant, Brij76 showed the highest ALA penetration. Furthermore, this system also established the highest in vivo PpIX biosynthesis in hairy mice skin of C57BL/6. These results concluded that the transferosome of SL80-3 and Brij76 produced the best results in both ALA penetration and PpIX biosynthesis, and proved good correlation between them.

• Journal of Chest Surgery
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• v.33 no.5
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• pp.377-384
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• 2000

Background: Numerous studies of safe, long term preservation for lung transplantation have been performed using ex vivo models or in vivo single lung transplantation models. However, a safe preservation time which is applicable for clinical use is difficult to determine. We prepared LPDG solution for lung preservation study. In this study we examined the efficacy of LPDG(low potassium dextran glucose) solution in 24-hour lung preservation by using a sequential bilateral canine lung allotransplant model. Material and Method: Seven bilateral lung transplant procedures were performed using weight-matched pairs(24 to 25kg) of adult mongrel dogs. The donor lungs were flushed with LPDG solution and maintained hyperinflated with 100% oxygen at 1$0^{\circ}C$ for a planned ischemic time of 24 hours for the lung implanted first. After sequential bilateral lung transplantation, dogs were maintained on ventilators for 3 hours: arterial resistance were determined if the recipients hourly after bilateral reperfusion and compared with pretransplant-recipient values, which were used as controls. After 2hours of reperfusion, the chest X-ray, computed tomogram and lung perfusion scan were performed for assessmint of early graft lung function. Pathological examinations for ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery were performed. Result: Five of seven experiments successfully finished the whole assessments after bilateral reperfusion for three hours. Arterial oxygen tension in the recipients was markedly decrased in immediate reperfusion period but gradually recovered after reperfusion for three hours. The pulmonary artery and pulmonary vascular resistance showed singificant elevation(p<0.05 versus control values) but also recovered after reperfusion for three hours(p<0.05 versus immediate period value). The ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery showed reversible mild injury in 24 hours of lung perservation and reperfusion. Conclusion : This study suggests that LPDG solution provides excellent preservation in a canine model in which the dog is completely dependent on the function of the transplanted lung.

• The Plant Pathology Journal
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• v.24 no.4
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• pp.453-460
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• 2008

In the course of in vitro and in vivo screening for bioherbicidal agents, a hyphomycete fungus, Myrothecium sp. F0252 was selected as a candidate for the biocontrol of weeds. The isolate was identified as Myrothecium roridum Tode ex. Fries based on the morphological characteristics and 18S ribosomal DNA sequence analysis and registered as Myrothecium roridum F0252. In order to evaluate the in vitro effect of M. roridum F0252 on germination of ladino clover and white clover (Trifolium repens L.) seeds, spore solution of the fungus was employed in two concentrations, $6.5{\times}10^6$ and $2.5{\times}10^7$ spores per mL and then inoculated to the seeds. The fungal spores inhibited the seed germination, infected the seedlings, and caused an abnormal withering and inhibition of seedling growth. In addition, when the herbicidal activity of crude ethyl acetate extract from the liquid culture was assessed on a mini-plant, duck-weed (Lemna paucicostata (L.) Hegelm.), the extract showed high inhibitory effect at the level of $12.5{\mu}g$ per mL. On the other hand, in vivo herbicidal activity of M. roridum F0252 was evaluated by a whole plant spray method. M. roridum F0252 exhibited strong and broad-spectrum herbicidal activity. The herbicidal values ranged from 95-100% against 7 weeds, including Abutilon avicennae and Xanthium strumarium, and 70-80% against Digitaria sanguinalis and Sagittaria pygmaea. When the nutritional utilization (95 carbon sources) pattern of M. roridum F0252 was investigated, it varied with water activity ($a_w$) and temperature conditions, supplying good, basic information in regard to nutritional utilization for proper cultivation and formulation. Our results showed that M. roridum F0252 might be used as a potential biocontrol agent against weedy plants.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.3
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• pp.161-168
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• 2009

In the peripheral nerves, injury-induced cytokines and growth factors perform critical functions in the activation of both the MEK/ERK and JAK/STAT3 pathways. In this study, we determined that nerve injury-induced ERK activation was temporally correlated with STAT3 phosphorylation at the serine 727 residue. In cultured Schwann cells, we noted that ERK activation is required for the serine phosphorylation of STAT3 by neuropoietic cytokine interleukin-6 (IL-6). Serine phosphorylated STAT3 by IL-6 was transported into Schwann cell nuclei, thereby indicating that ERK may regulate the transcriptional activity of STAT3 via the induction of serine phosphorylation of STAT3. Neuregulin-1 (NRG) also induced the serine phosphorylation of STAT3 in an ERK-dependent fashion. In contrast with the IL-6 response, serine phosphorylated STAT3 induced by NRG was not detected in the nucleus, thus indicating the non-nuclear function of serine phosphorylated STAT3 in response to NRG. Finally, we determined that the inhibition of ERK prevented injury-induced serine phosphorylation of STAT3 in an ex-vivo explants culture of the sciatic nerves. Collectively, the results of this study show that ERK may be an upstream kinase for the serine phosphorylation of STAT3 induced by multiple stimuli in Schwann cells after peripheral nerve injury.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2405-2425
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• 2014

Radiation exposure leads to several pathophysiological conditions, including oxidative damage, inflammation and fibrosis, thereby affecting the survival of organisms. This review explores the radiation countermeasure properties of fourteen (14) plant extracts or plant-derived compounds against these cellular manifestations. It was aimed at evaluating the possible role of plants or its constituents in radiation countermeasure strategy. All the 14 plant extracts or compounds derived from it and considered in this review have shown some radioprotection in different in vivo, ex-vivo and or in vitro models of radiological injury. However, few have demonstrated advantages over the others. C. majus possessing antioxidant, anti-inflammatory and immunomodulatory effects appears to be promising in radioprotection. Its crude extracts as well as various alkaloids and flavonoids derived from it, have shown to enhance survival rate in irradiated mice. Similarly, curcumin with its antioxidant and the ability to ameliorate late effect of radiation exposure, combined with improvement in survival in experimental animal following irradiation, makes it another probable candidate against radiological injury. Furthermore, the extracts of P. hexandrum and P. kurroa in combine treatment regime, M. piperita, E. officinalis, A. sinensis, nutmeg, genistein and ginsan warrants further studies on their radioprotective potentials. However, one that has received a lot of attention is the dietary flaxseed. The scavenging ability against radiation-induced free radicals, prevention of radiation-induced lipid peroxidation, reduction in radiation cachexia, level of inflammatory cytokines and fibrosis, are some of the remarkable characteristics of flaxseed in animal models of radiation injury. While countering the harmful effects of radiation exposure, it has shown its ability to enhance survival rate in experimental animals. Further, flaxseed has been tested and found to be equally effective when administered before or after irradiation, and against low doses (${\leq}5Gy$) to the whole body or high doses (12-13.5 Gy) to the whole thorax. This is particularly relevant since apart from the possibility of using it in pre-conditioning regime in radiotherapy, it could also be used during nuclear plant leakage/accidents and radiological terrorism, which are not pre-determined scenarios. However, considering the infancy of the field of plant-based radioprotectors, all the above-mentioned plant extracts/plant-derived compounds deserves further stringent study in different models of radiation injury.

• Mycobiology
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• v.42 no.2
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• pp.174-180
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• 2014

We analyzed the genetic diversity of Cylindrocarpon destructans isolates obtained from Korean ginseng (i.e., Panax ginseng) roots by performing virulence tests and nuclear ribosomal gene internal transcribed spacer (ITS) and mitochondrial small subunit (mt SSU) rDNA sequence analysis. The phylogenetic relationship analysis performed using ITS DNA sequences and isolates from other hosts helped confirm that all the Korean C. destructans isolates belonged to Nectria/Neonectria radicicola complex. The results of in vivo and ex vivo virulence tests showed that the C. destructans isolates could be divided into two groups according to their distinctive difference in virulence and the genetic diversity. The highly virulent Korean isolates in pathogenicity group II (PG II), together with foreign isolates from P. ginseng and P. quinquefolius, formed a single group. The weakly virulent isolates in pathogenicity group I, together with the foreign isolates from other host plants, formed another group and exhibited a greater genetic diversity than the isolates of PG II, as confirmed by the mt SSU rDNA sequence analysis. In addition, as the weakly virulent Korean isolates were genetically very similar to the foreign isolates from other hosts, they were likely to originate from hosts other than the ginseng plants.

• IMMUNE NETWORK
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• v.13 no.3
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• pp.86-93
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• 2013

In the present study, we investigated if priming of autoreactive $CD8^+T$ cells would be inhibited by competitive peptides for major histocompatibility complex (MHC) class I binding. We used a mouse model of vitiligo which is induced by immunization of $K^b$-binding tyrosinase-related protein 2 (TRP2)-180 peptide. Competitive peptides for $K^b$ binding inhibited IFN-${\gamma}$production and proliferation of TRP2-180-specific $CD8^+T$ cells upon ex vivo peptide restimulation, while other MHC class I-binding peptides did not. In mice, the capability of inhibition was influenced by T-cell immunogenicity of the competitive peptides. The competitive peptide with a high T-cell immunogenicity efficiently inhibited priming of TRP2-180-specific $CD8^+T$ cells in vivo, whereas the competitive peptide with a low T-cell immunogenicity did not. Taken together, the inhibition of priming of autoreactive $CD8^+T$ cells depends on not only competition of peptides for MHC class I binding but also competitive peptide-specific $CD8^+T$ cells, suggesting that clonal expansion of autoreactive T cells would be affected by expansion of competitive peptide-specific T cells. This result provides new insights into the development of competitive peptides-based therapy for the treatment of autoimmune diseases.

• Clinical and Experimental Pediatrics
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• v.58 no.6
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• pp.199-205
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• 2015

Severe aplastic anemia (SAA) is a life-threatening disorder for which allogeneic hematopoietic stem cell transplantation (HSCT) is the current available curative treatment. HSCT from matched sibling donors (MSDs) is the preferred therapy for children with acquired SAA. For patients who lack MSDs, immunosuppressive therapy (IST) is widely accepted as a first-line treatment before considering HCT from an unrelated donor (URD). Given the recent progress in HSCT using URDs for childhood SAA, well-matched URDs became a realistic alternative for pediatric patients who have no suitable related donors and who are refractory to IST. However, it is quite challenging to treat patients with refractory SAA who lack suitable related or URDs. Even though haploidentical HSCT from genetically mismatched family members seemed to be an attractive procedure with the amazing benefit of readily available donors for most patients, early attempts were disappointing because of refractory graft-versus-host disease (GVHD) and excessively high transplant-related mortality. Recent advances with effective ex vivo depletion of T cells or unmanipulated in vivo regulation of T cells, better supportive care, and optimal conditioning regimens have significantly improved the outcome of haploidentical transplant. Besides considerable progress in the treatment of malignant diseases, recent emerging evidences for haploidentical HSCT in SAA has provided additional therapeutic options for patients with refractory diseases. Further improvements to decrease the rates of graft failure, GVHD, and infectious complications will facilitate the emergence of haploidentical HSCT as a front-line therapy for treating acquired SAA in children and adolescents who have no suitably matched donors.

• Toxicological Research
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• v.3 no.2
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• pp.97-110
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• 1987

The effects of 5 novel hepatotrophic agents, dithiol malonate derivatives (DMDs; DMD1-DMD5), on the liver microsomal lipid peroxidation induced by carbon tetrachloride $(CCl_4)$ and the correlations with the changes of microsomal electron transport system were investigated. All DMDs were found to inhibit the lipid peroxidation induced by $CCl_4$ in mice and rats as well in vitro liver microsomal system. Therefore, each DMD seemed to have direct mode of action on liver microsomes to inhibit the lipid peroxidation. As an ex vivo study, the induced lipid peroxidation by $CCl_4$ and the changes in electron transport system were determined with liver microsomes obtained from rats chronically treated with DMDs for 7 days. The induced lipid peroxide contents in liver microsomal system were lower in DMD1, DMD2 and DMD3 treated group, but higher in DMD4 and DMD5 group when compared to the control group. Cyt. p.450 contents in the microsomes were decreased by the treatment with DMD1, DMD2 and DMD3, but increased significantly by DMD4 with great extent and by DMD5 with less extent. The cyt. p-450 isozymes induced by treatment of DMD4 and DMD5 were identified as 3-methylcholanthrene (MC) type. The NADPH cyt. -C reductase activities of the microsomes treated with DMD1, DMD2, DMD4 and DMD5 were increased in the range of around 20% to 50%, but decreased with DMD3, All DMDs increased dyt. $-b_5$ content and did not alter NAdH-cyt, $-b_5$ reductase activities in the microsomes. In summary, the 5 novel hepatotrophic agents (DMDs) markedly protected against lipid peroxidation induced by $CCl_4$ in vivo and in vitro possibly through the mechanism of direct action on the liver microsomes. The degree of inhibition produced by DMDs on lipid peroxidation induced by $CCl_4$ seemed to coincide rather with cyt. p-450 contents than with other components of liver microsomal electron transport system including NADPH-cyt, -C reductase.