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Excess body weight is a major risk factor for type 2 diabetes (T2D) and associated metabolic complications, and weight loss has been shown to improve glycemic control and decrease morbidity and mortality in T2D patients. Weight-loss strategies using dietary interventions produce a significant decrease in diabetes-related metabolic disturbance. We have previously reported that the supplementation of low molecular chitosan oligosaccharide (GO2KA1) significantly inhibited blood glucose levels in both animals and humans. However, the effect of GO2KA1 on obesity still remains unclear. The aim of the study was to evaluate the anti-obesity effect of GO2KA1 on lipid accumulation and adipogenic gene expression using 3T3-L1 adipocytes in vitro and plasma lipid profiles using a Sprague-Dawley (SD) rat model. Murine 3T3-L1 preadipocytes were stimulated to differentiate under the adipogenic stimulation in the presence and absence of varying concentrations of GO2KA1. Adipocyte differentiation was confirmed by Oil Red O staining of lipids and the expression of adipogenic gene expression. Compared to control group, the cells treated with GO2KA1 significantly decreased in intracellular lipid accumulation with concomitant decreases in the expression of key transcription factors, peroxisome proliferator-activated receptor gamma (PPAR&gamma, ) and CCAAT/enhancer-binding protein alpha (CEBP/&alpha, ). Consistently, the mRNA expression of downstream adipogenic target genes such as fatty acid binding protein 4 (FABP4), fatty acid synthase (FAS), were significantly lower in the GO2KA1-treated group than in the control group. In vivo, male SD rats were fed a high fat diet (HFD) for 6 weeks to induced obesity, followed by oral administration of GO2KA1 at 0.1 g/kg/body weight or vehicle control in HFD. We assessed body weight, food intake, plasma lipids, levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) for liver function, and serum level of adiponectin, a marker for obesity-mediated metabolic syndrome. Compared to control group GO2KA1 significantly suppressed body weight gain (185.8 &plusmn, 8.8 g vs. 211.6 &plusmn, 20.1 g, p &lt, 0.05) with no significant difference in food intake. The serum total cholesterol, triglyceride, and low-density lipoprotein (LDL) levels were significantly lower in the GO2KA1-treated group than in the control group, whereas the high-density lipoprotein (HDL) level was higher in the GO2KA1 group. The GO2KA1-treated group also showed a significant reduction in ALT and AST levels compared to the control. Moreover, serum adiponectin levels were significantly 1.5-folder higher than the control group. These in vivo and in vitro findings suggest that dietary supplementation of GO2KA1 may prevent diet-induced weight gain and the anti-obesity effect is mediated in part by inhibiting adipogenesis and increasing adiponectin level.

We prepared hyaluronic acid (HA)-based nanogels conjugated with dihydroxyflavone (DHF) and evaluated their cellular uptake and antitumoral efficiency. 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) was used as a conjugation agent for esterification between DHF and HA as well as crosslinking among HA. The conjugations were confirmed by nuclear magnetic resonance spectroscopy, UV/vis spectroscopy, and high-performance liquid chromatography. The size and Zeta-potential of the DHF/HA nanogels were reduced with an increase in the concentration of DMTMM due to the involvement of more HA molecules for the conjugation reactions. The DHF/HA nanogel with a smaller size was greatly taken up by two kinds of tumor cells (HeLa and HepG2), compared to NIH3T3. The cell viabilities were reduced to approximately 60% for HeLa and HepG2 cells after 48 h post treatment with DHF/HA nanogels.

Hyaluronan has diverse biological activities depending on its molecular size. The hyaluronan fragments (50 kDa) can decrease adipogenic differentiation in vitro. However, in vivo anti-obesitic effects of hyaluronan fragments have not been elucidated. Therefore, we examined the anti-obesity effects of hyaluronan fragments on high-fat diet induced obesity in C57BL/6 mice. Oral administration of hyaluronan fragments (200 mg/kg for 8 weeks) decreased body weight, adipose tissues, serum lipid (low-density lipoprotein cholesterol, triglyceride), and leptin level. Hyaluronan fragments decreased the hypertrophy of adipose tissue and ameliorated liver steatosis. The mRNA expression of leptin was reduced in adipocyte by treatment with hyaluronan fragments. Additionally, hyaluronan fragments enhanced the mRNA expression of PPAR-α and its target genes UCP-2 and decreased mRNA expression of PPAR- γ and fatty acid synthase in liver. In conclusions, hyaluronan fragments had marked effects on inhibiting the development of obesity in obese mice fed the high-fat diet. It suggested that enhancing PPAR-α and suppressing PPAR-γ expression are two possible mechanisms for the anti-obesitic effect of hyaluronan fragments.

Acorn-derived foods are commonly marketed in Korea, but their beneficial health effects have not been extensively explored. The aim of this study was to investigate the anti-inflammatory and antiasthmatic effects of an ethanol extract (AEx) from acorn (Quercus acutissima CARR.) in murine macrophage RAW264.7 cells and ovalbumin (OVA)-induced asthma model mice. The AEx at concentrations less than 100 µg/mL significantly, dose dependently attenuated the production of nitric oxide and the expression of inducible nitric oxide synthase, cyclooxygenase-2 and interleukin-1β (IL-1β) in RAW264.7 cells. The AEx (100 or 300 mg/kg/day) also inhibited the production of tumor necrosis factor-α and T-helper 2 (Th2) type cytokines (IL-4 and IL-13) in both the lung tissues and bronchoalveolar lavage fluid of the OVA-induced asthma model mice. These results suggest that the AEx has suppressive effects on asthma through its anti-inflammatory action both in vitro and in vivo. PRACTICAL APPLICATIONS AEx may be useful for preventing inflammatory diseases, such as allergic asthma, and may thus be effectively used as a natural anti-inflammatory ingredient in health food or pharmaceuticals.

A fucoidan, isolated from Korean Undaria pinnatifida spoprophyll (UP-F), was investigated for its immunomodulating activity on murine macrophages and splenocytes, and its activity was compared with that of fucoidan from Fucus vesiculosus (FV-F). Treatment of UP-F resulted in inhibition of the growth of murine macrophage RAW 264.7 cells, but its cytotoxicity was not observed in normal murine splenocytes. FV-F was shown to be highly cytotoxic to both immune cells, and its cytotoxic activity was higher than that of UP-F. Treatment of UP-F induced TNF-α in a dose-dependent manner from two types of macrophages, RAW 264.7 cells and murine peritoneal macrophages. The TNF-α-inducing activity of UP-F was higher than that of FV-F. UP-F also actively induced chemokines (RANTES and MIP-1α) from RAW 264.7 cells. Furthermore, treatment of UP-F gave rise to activation of murine splenocytes to produce cytokine (IL-6) and chemokines (RANTES and MIP-1α), showing significantly higher activity than that of FV-F. These results indicate that UP-F is less cytotoxic to immune cells than FV-F, and possesses immunomodulating activity to produce cytokines and chemokines from macrophages and splenocytes.

Streptomyces sp. Y-110, isolated from soil, modified compactin to pravastatin, a therapeutic agent for hypercholesterolemia. In a batch culture, the highest production of pravastatin was 340 mg l−1 from 750 mg compactin l−1 in 24 h. By intermittent feeding of compactin into the culture medium, both the compactin concentration and its conversion increased to 2000 mg l−1 and 1000 mg pravastatin l−1, respectively, with the conversion rate of 10 mg l−1 h−1. Continuous feeding of compactin increased production of pravastatin to 15 mg l−1 h−1.

The ethyl acetate extracts from the liquid cultures of Coriolus versicolor, Phellinus linteus, and Hericium erinaceus showed significant antibacterial activities against Escherichia coli K88, E. coli K99, E. coli 987P, and Salmonella typhimurium 14058 causing bacterial diarrhea in Korean house pigs and chicken. Of these extracts, Coriolus versicolor extract showed the highest antibacterial activity. In addition, these extracts also showed significant growth inhibition against Staphylococcus aureus CARM3230 and E. coli CARM1381 which are known as kanamycin and ampicillin-resistant strains. These results showed that the mushroom extracts could be developed as a livestock feed additives that can replace commercial antibiotics, and also could be good resources for the development of a new antibacterial agent.