Se Young Choung

Synergistic immunostimulating activity of pidotimod and red ginseng acidic polysaccharide against cyclophosphamide-induced immunosuppression.

We investigated the synergistic effect of combined treatment with red ginseng acidic polysaccharide (RGAP) from Panax ginseng C.A. Meyer and pidotimod in cyclophosphamide-treated mice. The combination of pidotimod and RGAP restored concanavalin A-induced splenic T cell proliferation and LPS-stimulated B cell proliferation significantly. The production of nitric oxide from peritoneal macrophages was increased by the combinations. NK cell activity was increased by RGAP alone or in combination with pidotimod. A synergistic increase in the level of serum IL-12 and interferongamm was observed when the combination of the two was used. RGAP alone or in combination with pidotimod modulated the level of serum C-reactive protein to a near-normal level. These results indicate that combinations of pidotimod and RGAP are synergistic and suggest that combination therapy using pidotimod and RGAP for improving immune activity may provide an additional benefit over the use of the two drugs by themselves.

Antihyperglycemic and antihyperlipidemic action of Cinnamomi Cassiae (Cinnamon bark) extract in C57BL/Ks db/db mice.

In previous study, the anti-diabetic effect of Cinnamomi Cassiae extract (Cinnamon bark: Lauraceae) in a type II diabetic animal model (C57BIKsj db/db) has been reported. To explore their mechanism of action, in present study, the effect of cinnamon extract on anti-hyperglycemia and anti-hyperlipidemia was evaluated by measuring the blood glucose levels, serum insulin, and adiponectin levels, serum and hepatic lipids, PPARα mRNA expression in liver and PPARγ mRNA expression in adipose tissue, respectively. Male C57BIKs db/db mice were divided into a diabetic group and cinnamon extract treated group and examined for a period of 12 weeks (200 mg/kg, p.o). The fasting blood glucose and postprandial 2 h blood glucose levels in the cinnamon treated group were significantly lower than those in the control group (p < 0.01), whereas the serum insulin and adiponectin levels were significantly higher in the cinnamon treated group than in the control group (p < 0.05). The serum lipids and hepatic lipids were improved in the cinnamon administered group. Also the PPARα mRNA (liver) and PPARγ mRNA (adipose tissue) expression levels were increased significantly in the cinnamon treated group (p < 0.05). Our results suggest that cinnamon extract significantly increases insulin sensitivity, reduces serum, and hepatic lipids, and improves hyperglycemia and hyperlipidemia possibly by regulating the PPAR-medicated glucose and lipid metabolism.

Separation of the antioxidant compound quercitrin from Lindera obtusiloba Blume and its antimelanogenic effect on B16F10 melanoma cells.

Considering the growing evidence of the presence of antioxidant compounds in plant extracts, the objectives of this study were to identify antioxidant compounds in Lindera obtusiloba Blume (Lauraceae) and to evaluate their antimelanogenic activities on B16F10 melanoma cells. Organic solvent fractions were separated from L. obtusiloba extracts (LOE). The ethyl acetate fraction (LOE-E) was significantly active against oxidative damage induced by tert-butyl hydroperoxide in primary rat hepatocytes. Two single purified compounds, quercitrin (quercetin-3-O-α-L-rhamnopyranoside) and afzelin (kaempferol-3-O-α-L-rhamnoside), were identified by HPLC and NMR. These compounds were evaluated for antioxidant activities by 1,1-diphenyl 2-picrylhydrazyl (DPPH) radical scavenging assay and ferric reducing antioxidant power (FRAP) assay, and for their antimelanogenic activities by tyrosinase inhibitory assay melanin formation inhibition assay and Western bolt analysis for the signaling pathway. The significant effects of quercitrin on antioxidant and antimelanogenic activities, and signal modulation of ERK and MITF in B16F10 melanoma cells were observed. This is the first report to identify quercitrin in L. obtusiloba and its whitening effect.

Effects of chitosan on serum cytokine levels in elderly subjects.

This study was done to evaluate the immune enhancing activity of health function food, chitosan by clinical study. To evaluate the effect of chitosan on serum cytokine levels in elderly adults, 5.1 g/day of chitosan was administrated to volunteers (age range 74-86, mean 80±3 year old) for 8 weeks.This study was IRB approved and all patients gave informed consent prior to examination.The clinical study showed that the increase of IL-2, IL-12, and TNF-α production were a little greater in chitosan administered group as in the control group but there were no significant differences. In the safety study with blood biochemical test, it has been shown that all safety parameters in liver were in normal ranges. Also there were no significant changes in the values of the electrolytes, blood lipids profiles, glucose levels and leucocytes number. With these results we have not found any safety problems after the administration of chitosan for 8 weeks. In this study, there was a tendency of immune enhancing effect of chitosan at the experimental dose, which is generally used. More intense clinical study will be needed to confirm statistical significance.

Treatment of GABA from Fermented Rice Germ Ameliorates Caffeine-Induced Sleep Disturbance in Mice

γ-Aminobutyric acid (GABA), a major inhibitory neurotransmitter in the mammalian central nervous system, is involved in sleep physiology. Caffeine is widely used psychoactive substance known to induce wakefulness and insomnia to its consumers. This study was performed to examine whether GABA extracts from fermented rice germ ameliorates caffeine-induced sleep disturbance in mice, without affecting spontaneous locomotor activity and motor coordination. Indeed, caffeine (10 mg/kg, i.p.) delayed sleep onset and reduced sleep duration of mice. Conversely, rice germ ferment extracts-GABA treatment (10, 30, or 100 mg/kg, p.o.), especially at 100 mg/kg, normalized the sleep disturbance induced by caffeine. In locomotor tests, rice germ ferment extracts-GABA slightly but not significantly reduced the caffeine-induced increase in locomotor activity without affecting motor coordination. Additionally, rice germ ferment extracts-GABA per se did not affect the spontaneous locomotor activity and motor coordination of mice. In conclusion, rice germ ferment extracts-GABA supplementation can counter the sleep disturbance induced by caffeine, without affecting the general locomotor activities of mice.

Protective effect of the edible brown alga Ecklonia stolonifera on doxorubicin-induced hepatotoxicity in primary rat hepatocytes

As part of our efforts to isolate anti‐hepatotoxic agents from marine natural products, we screened the ability of 14 edible varieties of Korean seaweed to protect against doxorubicin‐induced hepatotoxicity in primary rat hepatocytes.

Whole genomic expression analysis of octachlorostyrene-induced chronic toxicity in Caenorhabditis elegans

In recent years, microarray technology has enabled the investigation of possible mechanisms the expression of genes related to toxic compounds. We used a C. elegans whole genome microarray to observe and evaluate the chronic toxicity of the free-living nematode Caenorhabditis elegans (C. elegans) after exposure to octachlorostyrene, (OCS), a by-product in the manufacture of many chlorinated hydrocarbons. In this study, we examined sublethal toxicity, egg hatching, and movement of octachlorostyrene over three generations using a nematode growth medium (NGM) agar plate. In the third generation, OCS affected the fecundity rate of C. elegans. Specifically, the number of worm and eggs decreased significantly to about 50% of control (p < 0.05). In microarray experiments, total RNA was isolated at 0, 2 and 3 generations following treatment of OCS, and hybridized to the microarray containing about 22,000 C. elegans genes. Dye swaps were performed. After data analysis, we identified a total of 1,294 genes that were differentially expressed through generations.

Effect of Coenzyme Q10 Supplementation in Statin-Treated Obese Rats.

Statins, HMG-CoA reductase inhibitors, are known to cause serious muscle injuries (e.g. myopathy, myositis and rhabdomyolysis), and these adverse effects can be rescued by co-administration of coenzyme Q10 (CoQ10) with statins. The goal of the current research is to assess the efficacy of combined treatment of CoQ10 with Atorvastatin for hyperlipidemia induced by high-fat diet in SD rats. 4-week-old Sprague-Dawley male rats were fed normal diet or high-fat diet for 6 weeks. Then, rats were treated with either Statin or Statin with various dosages of CoQ10 (30, 90 or 270 mg/kg/day, p.o.) for another 6 weeks. Compared to Statin only-treatment, CoQ10 supplementation significantly reduced creatine kinase and aspartate aminotransferase levels in serum which are markers for myopathy. Moreover, CoQ10 supplementation with Statin further reduced total fat, triglycerides, total cholesterol, and low-density lipoprotein-cholesterol. In contrast, the levels of high-density lipoprotein-cholesterol and CoQ10 were increased in the CoQ10 co-treated group. These results indicate that CoQ10 treatment not only reduces the side effects of Statin, but also has an anti-obesity effect. Therefore an intake of supplementary CoQ10 is helpful for solving problem of obese metabolism, so the multiple prescription of CoQ10 makes us think a possibility that can be solved in being contiguous to the obesity problem, a sort of disease of the obese metabolism.

Aster spathulifolius Maxim extract reduces body weight and fat mass in obese humans.

Aster spathulifolius Maxim (AS), a perennial herb of the genus Aster within the family Asteraceae, induced weight loss in a rat model of diet-induced obesity. We hypothesized that AS could also reduce body weight in obese humans. Therefore, we performed a randomized, double-blind, placebo-controlled clinical trial in Korea to evaluate the effect of AS extract (ASE) on body weight and fat mass and its safety in obese humans. Forty-four obese participants (body mass index [BMI], 25-30 kg/m(2)) aged ≥20 years were randomly assigned to the placebo or ASE group (700 mg/d of ASE) and were instructed to take a once-daily pill for 12 weeks. Weight, BMI, waist circumference, fat mass (measured using bioimpedance, dual-energy X-ray absorptiometry, and computed tomography), and laboratory tests were assessed at baseline and at 12 weeks. Body weight significantly decreased after 12 weeks of treatment in the ASE group (placebo vs ASE: -0.08 ± 2.11 kg vs -3.30 ± 3.15 kg, P < .05), and so did body fat mass (placebo vs ASE; bioimpedance method: -0.51 ± 1.89 kg vs -2.38 ± 2.30 kg, P < .05; dual-energy X-ray absorptiometry: 0.38 ± 1.59 kg vs -2.26 ± 2.37 kg, P < .05). Changes in lipid profiles, fasting plasma glucose, and hemoglobin A1c did not differ between the 2 groups. No drug-related adverse events were observed during the study. In conclusion, ASE significantly decreases body weight and fat mass in obese humans, suggesting that ASE may be a potential therapeutic candidate for reducing obesity.

In vitro efficacy evaluation for prevention of diabetes and diabetic complications using Aster sphathulifolius

The efficacy of Aster sphathulifolius (AS) for evaluation of preventive potencies against diabetes and diabetic complications was analyzed by assessment of inhibitory effects against advanced glycation end-products (AGEs) formation, rat lens aldose reductase (RLAR), α-glucosidase activity, and scavenging effects against DPPH. The 50% ethanol extract showed the highest DPPH radical scavenging activity (82.38%) at a concentration of 100 μg/mL, exhibited the most potent AGEs formation inhibitory effect (93.88%) at a concentration of 200 μg/mL, showed the most potent RLAR inhibitory effect (86.44%) at a concentration of 11.11 μg/mL. The 95% ethanol extract showed a potent α-glucosidase inhibitory activity (19.16%) at a concentration of 1 mg/mL. The 50% ethanol extract value was 16.79%. The 50% ethanol extract exhibited the most potent antioxidant and preventive actions against diabetes and diabetic complications and can, thus, be a source of valuable compounds for prevention of diabetes and diabetic complications.