Hyeung-Sik Lee

Effects of ß-glucan fromAureobasidium pullulans on acute inflammation in mice

The effects of ß-glucan isolated fromAureobasidium pullulans were observed on acute xylene-induced inflammation, ß-glucan at a dose of 62.5, 125 or 250 mg/kg were administered once orally to xylene-treated mice (0.03 mL of xylene was applied on the anterior surface of the right ear to induce inflammation), and the body weight change, ear weight, histological profiles and histomorphometrical analyses of ear were conducted upon sacrifice. The xylene was topically applied 30min after dosing with ß-glucan. The results were compared to those of diclofenac, indomethacin and dexamethasone (15 mg/kg injected once intraperitoneally). All animals were sacrificed 2 h after xylene application. Xylene application resulted in marked increases in induced ear weights compared to that of intact control ear; hence, the differences between intact and induced ear were also significantly increased. The histological characteristics of acute inflammation, such as severe vasodilation, edematous changes of skin and infiltration of inflammatory cells, were detected in xylene-treated control ears with marked increase in the thickness of the ear tissues. However, these xylene-induced acute inflammatory changes were significantly and dose-dependently decreased by ß-glucan treatment. We conclude that ß-glu-can fromA. pullulans has a somewhat favorable effect in the reduction of the acute inflammatory responses induced by xylene application in mice.

28 Days repeated oral dose toxicity test of aqueous extracts of mahwangyounpae-tang, a polyherbal formula.

Mahwangyounpae-tang (MT), consisting of 22 types of herbal extracts has been used for thousands of years in Korean traditional medicine for the oral treatment of respiratory diseases including asthma. As part of a safety evaluation of MT extract for use in asthma, the 28 day repeat oral dose toxicity of an aqueous MT extract was evaluated at 800, 400 and 200mg/kg per day dose levels. The results showed that no significant toxicological changes were observed when 200 and 400mg/kg per day of MT extract was administered to rats. But when the dose was increased to 800 mg/kg per day, increases of body weights, food consumptions, and heart and kidney weights were observed with hypertrophy of heart and tubular necrosis of kidney. Besides this, no other signs of toxicity were observed. Based on these results, it can be concluded that the no observed adverse effect level of MT extract is 400mg/kg per day. Therefore, the use of MT is expected to be safe because 30 mg/kg was shown to be pharmacologically effective in mice and the high dose heart and kidney findings are not considered to represent any safety concern for humans.

Effects of Polycan, a β-glucan, on experimental periodontitis and alveolar bone loss in Sprague-Dawley rats

BACKGROUND AND OBJECTIVE Polycan is a promising candidate for the treatment of periodontal disease. This study was undertaken to examine whether Polycan, a type of β-glucan, has a protective effect on ligature-induced experimental periodontitis and related alveolar bone loss in Sprague-Dawley rats. MATERIAL AND METHODS  Polycan was orally administered, daily, for 10 d, at 21.25, 42.5 or 85 mg/kg, beginning 1 d after ligation. Changes in body weight and alveolar bone loss were monitored, and the anti-inflammatory effects of Polycan were determined by measuring the levels of myeloperoxidase (MPO), interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) in gingival tissue. We also evaluated inducible nitric oxide synthase (iNOS) activity and malondialdehyde (MDA) concentrations as a measure of the antioxidant effect. RESULTS Ligature placement led to a marked decrease in body weight, increased alveolar bone loss and increased concentrations of MPO, IL-1β, TNF-α and MDA, as well as increased iNOS activity and inflammatory cell infiltration and decreased collagen-fiber content. Histological examination revealed increases in the number and activity of osteoclast cells, decreases in alveolar bone volume and elevated percentages of osteclasts on the alveolar bone surface. Daily oral treatment with 42.5 or 85 mg/kg of Polycan for 10 d led to significant, dose-dependent inhibition of the effect of ligature placement. CONCLUSION Taken together, these results suggest that 10 d of oral treatment with Polycan effectively inhibits ligature placement-induced periodontitis and related alveolar bone loss via an antioxidant effect.

Micronucleus Test of DHU001, a Polyherbal Formula, in Bone Marrow Cells of Male ICR Mice

The genotoxic effects of DHU001, a polyherbal formula were evaluated using the mouse micronucleus test. DHU001 was administered once a day for 2 continuous days by oral gavage to male ICR mice at doses of 2000, 1000 and 500 mg/kg. Cyclophosphamide was used as a known geno-toxic agent in a positive control. The appearance of a micronucleus is used as an index for genotoxic potential. In addition, the changes on the total white blood cells and differential counts on the lymphocytes, neutrophils, eosinophils, basophils and monocytes in the prepared blood smears were also conducted to observe the possible immunosuppression. The results indicats that DHU001 showed no genotoxicity effects up to 2000 mg/kg dosing levels and did not influenced on the total white blood cells and differential counts. In addition, it is also considered that there were no problems from cytotoxicity of DHU001 tested in this study because the polychromatic erythrocyte ratio was detected as > 0.41 in all tested groups.

An immunohistochemical study of endocrine cells in the pancreas of the Red-bellied frog (Bombina orientalis)

The regional distribution and frequency of pancreatic endocrine cells in the red-bellied frog, Bombina orientalis, were studied by the immunohistochemical peroxidase anti-peroxidase (PAP) method using five types of specific mammalian antisera to insulin, glucagon, somatostatin, bovine pancreatic polypeptide (PP) and secretin. The frequency was calculated as the mean number of each endocrine cell type/1,000 total cells (including exocrine and endocrine cells) using an automated image analysis process. The percentage of each immunoreactive (IR) cell species to the total IR cell population was also calculated. In the pancreas of the red-bellied frog, all five endocrine cell types were demonstrated. Insulin IR cells were located in the pancreas as single cells or islet-like clusters. The latter were localized in central regions. The insulin-IR cells showed a frequency of 65.40 plus/minus 14.56/1,000 cells. Glucagon IR cells were also detected as single cells or as clusters but in the case of clusters, two distributional patterns were detected - a central core type and a marginally distributed type. They showed an abundance of 32.70 plus/minus 7.32/1,000 cells. Somatostatin-IR cells were dispersed throughout the pancreatic parenchyma as single cells, three to four cells, or clusters. The clusters were located in the marginal regions. The somatostatin-IR cell frequency was 19.40 plus/minus 6.52/1000 cells. PP-IR cells were randomly distributed throughout the pancreatic parenchyma as single cells with a frequency of 14.70 plus/minus 4.92/1,000 cells. Secretin-IR cells were demonstrated as clusters or as single cells, and as clusters they occupied the central regions. They showed a frequency of 39.60 plus/minus 10.36/1,000 cells. This is the first report of the presence of secretin-IR cells in amphibian pancreatic endocrine cells. Overall, there were 37.20 plus/minus 6.84% insulin-, 21.90 plus/minus 5.55% glucagon-, 11.60 plus/minus 4.33% somatostatin-, 8.60 plus/minus 2.72% PP- and 23.40 plus/minus 4.45% secretin-IR cells.

Immunohistochemistry of endocrine cells in the alimentary tract of the tree frog, hyla arborea japonica

The regional distribution and relative frequencies of endocrine cells were studied immunohistochemically (PAP methods) in the alimentary tract of the tree frog, Hyla arborea japonica, using specific antisera against serotonin, somatostatin, bovine Sp‐1/chromogranin (BCG), cholecystokinin (CCK)‐8, vasoactive intestinal polypeptide (VIP), gastrin, bombesin, secret in and pancreatic polypeptide (PP). Six kinds of endocrine cells were identified in this study. These immunoreactive cells were located in the gastric glands of stomach regions and in the basal portion of the epithelium of the intestinal tract or esophagus with variable frequencies. They were spherical or spindle‐shaped. Serotonin‐immunoreactive cells were observed in the whole alimentary tract including the esophagus. Somatostatin‐immunoreactive cells were also detected throughout the alimentary tract except the rectum. CCK‐8‐immunoreactive cells were observed from the pylorus to ileum. VIP‐immunoreactive cells were restricted to the rectum. Bombesin‐immunoreactive cells were restricted to the fundic gastric regions and gastrin‐immunoreactive cells were restricted to the pylorus. However, no BCG‐, secretin and PP‐immunoreactive cells were demonstrated in this study. In conclusion, the regional distribution and relative frequency of the endocrine cells in the alimentary tract of the tree frog were similar to other anuran species, but some differences which may be caused by feeding habits and species specification were also observed.

Decrease in intestinal endocrine cells in Balb/c mice with CT-26 carcinoma cells

The density of intestinal endocrine cells, in Balb/c mice with colon 26 (CT-26) carcinoma cells, were examined immunohistochemically at 28 days after implantation. After CT-26 cell administration there was a significant decrease in most of the intestinal endocrine cells (p < 0.01) compared with the control group. The significant quantitative changes in the intestinal endocrine cell density might contribute to the development of the gastrointestinal symptoms commonly encountered in cancer patients.

Genotoxicity testing of aqueous extracts of Mahwangyounpae-tang, a polyherbal formula

Mahwangyounpae-tang (MT), consisting of 22 types of herbal extracts has been used for thousands of years in Korean traditional medicine for the oral treatment of respiratory diseases including asthma. As part of a safety evaluation of MT extracts for use in asthma, the potential genotoxicity of an aqueous MT extract was evaluated using the standard battery of tests (bacterial reverse mutation assay; chromosomal aberrations assay; mouse micronucleus assay) recommended by Korea Food and Drug Administration (KFDA). The MT extract was determined not to be genotoxic under the conditions of the reverse mutation assay, chromosomal aberrations assay and mouse micronucleus assay. Use of MT is presently expected to be safe, as anticipated intake is small compared to the doses administered in the genotoxicity assays and may, after further toxicity research, prove to be a useful anti-asthma agent.

Oral Single Dose Toxicity Study of Low Molecular Fucoidan in Mice

This study was conducted to obtain information of the oral dose toxicity of low molecular fucoidan (LMF) in male and female mice. In order to calculate 50% lethal dose (LD50) and approximate lethal dose (LD), test material was once orally administered to male and female ICR mice at dose levels of 2000, 1000, 500, 250, 125 and 0 (vehicle control) mg/kg (body wt.). The mortality and the changes on body weight, clinical signs, gross observation and organ weight and histopathology of principle organs were monitored 14 days after LMF treatment. We could not find any mortalities, clinical signs, body weight changes and gross findings. In addition, significant changes in the organ weight and histopathology of principal organs were not observed except for some sporadic findings. The results obtained in this study suggest that LMF may not be toxic in mice and may be therefore safe for clinical use. The LD50 and approximate LD in mice after single oral dose of LMF were considered over 2000 mg/kg in both female and male mice.

Localization of endocrine cells in the gastrointestinal tract of the Manchurian chipmunk, tamias sibiricus barberi

The regional distribution and relative frequency of endocrine cells were studied immunohistochemically in the gastrointestinal tract (GIT) of the Manchurian chipmunk, Tamias sibiricus asiaticus. Six kinds of endocrine cells were identified in this study. 5‐hydroxytryptamine (5‐HT)‐immunoreactive cells were detected throughout the GIT. These cells were observed in moderate numbers in the pylorus, duodenum, jejunum, ileum, fundus, colon, and rectum. Somatostatin‐ and bovine pancreatic polypeptide (BPP)‐immunoreactive cells were also identified throughout the GIT. The former were abundant in the pylorus region while the latter were scattered in ileum and colon. Motilin‐immunoreactive cells were rarely detected in the small intestine. A few neurotensin‐immunoreactive cells were detected in jejunum, ileum and colon. Also, a few substance P‐immunoreactive cells were observed to be restricted to duodenum and jejunum