Jae-Youl Cho

Study of Macrophage Activation and Structural Characteristics of Purified Polysaccharides from the Fruiting Body of Hericium erinaceus

Most, if not all, Basidiomycetes mushrooms have biologically active polysaccharides showing potent antitumor activity with immunomodulating properties. These polysaccharides have various chemical compositions and belong primarily to the beta-glucan group. In this study, the crude water-soluble polysaccharide HEF-P, which was obtained from the fruiting body of Hericium erinaceus by hot water extraction and ethanol precipitation, was fractionated by DEAE-cellulose and Sepharose CL-6B column chromatographies. This process resulted in four polysaccharide fractions, named HEF-NP Fr I, HEF-NP Fr II, HEF-AP Fr I, and HEF-AP Fr II. Of these fractions, HEF-AP Fr II was able to upregulate the functional events mediated by activated macrophages, such as production of nitric oxide and expression of cytokines (IL-1beta and TNF-beta). The molecular mass of HEF-AP Fr II was estimated by gel filtration to be 13 kDa. Its structural characteristics were investigated by a combination of chemical and instrumental analyses, including methylation, reductive cleavage, acetylation, Fourier transform infrared spectroscopy (FT-IR), and gas chromatography-mass spectrometry (GC-MS). Results indicate that HEF-AP Fr II is a low-molecular-mass polysaccharide with a laminarin-like triple helix conformation of a beta-1,3-branched-beta-1,6-glucan.

Torilin ameliorates type II collagen-induced arthritis in mouse model of rheumatoid arthritis.

Advancements in rheumatoid-arthritis-(RA) therapies have shown considerable progresses in the comprehension of disease. However, the development of new potential agents with relative safety and efficacy continues and natural compounds have been considered as alternatives to identify new entities. Since previous in-vivo data and our in-vitro findings showed that torilin has a strong anti-inflammatory property, we further investigated its effect against collagen-induced-arthritis-(CIA) in mice. CIA-induced DBA/1J mice were treated with torilin or methotrexate (MTX) for 5-weeks. Arthritis severity was evaluated by arthritic score and joint histopathology. Draining lymph node (dLN), joint and peripheral-blood mononuclear-cell (PBMC) counts, and activation/localization of T-/B-lymphocytes, dendritic cells (DCs) and neutrophils were examined by FACS analysis. Serum anti-type-II-collagen-(CII) antibody levels and cultured-splenocyte and serum cytokines were also evaluated. Torilin markedly reduced CIA-induced arthritic score, histopathology and leukocyte counts. Besides, torilin suppressed CIA-activated T-cells including CD3+, CD3+/CD69+, CD8+, CD4+ and CD4+/CD25+ in dLNs or joints. It also modified CD19+ or CD20+/CD23+ (B-cells), MHCII+/CD11c+ (DCs) and Gr-1+/CD11b+ (neutrophil) subpopulations. It further depressed total anti-CII-IgG, anti-CII-IgG1 and anti-CII-IgG2a antibody productions. Moreover, while IFN-γ and IL-10 were not affected, torilin suppressed CIA-induced serum TNF-α, IL-1β and IL-6 levels. Interestingly, torilin also blocked IFN-γ, IL-17 and IL-6 cytokines while it did not affect IL-10 but enhanced IL-4 in splenocytes. These results show that torilin attenuated arthritis severity, modified leukocyte activations in dLNs or joints, and restored serum and splenocyte cytokine imbalances. Torilin may have immunomodulatory and anti-inflammatory properties with the capacity to ameliorate the inflammatory response in CIA-mice.

Probiotic properties of lactic acid bacteria isolated from Korean rice wine Makgeolli

Makgeolli, a traditional Korean alcoholic beverage, includes many kinds of lactic acid bacteria (LAB). In this study, 17 different LAB strains were isolated from makgeolli and their functional effects were examined. The 17 LAB were identified as eight Pediococcus acidilactici strains, six P. pentosaceus strains, two Lactobacillus curvatus strains, and one L. curstorum strain. Evaluation of nitric oxide (NO) production showed that all of the LAB strains except P. acidilactici 4 (PA4) produced higher amounts of NO than L. rhamnosus GG, indicating that they may have immunomodulatory effects. In addition, P. acidilactici 5 ( PA5), P. pentosaceus 5 (PP5), L. curvatus 1, and L. curstorum 1 exhibited high acid tolerance properties. PA5 and PP5 also exhibited good bile acid tolerance. Lastly, Caco-2 cell adhesion experiments revealed that PA5 had a high cell adhesion rate of 19-43%. In conclusion, PA5 may be useful as a probiotic for further food industry applications.

Zingerone protects keratinocyte stem cells from UVB-induced damage

The epidermis, the outermost layer of the skin, is a stratified epithelium that protects the body from the external environment. Keratinocyte stem cells (KSCs) are involved in epidermis homeostasis by maintaining epidermal integrity through a process of constant regeneration. Ultraviolet B (UVB) radiation is a major inducer of cellular damage in the epidermis. In this study, we investigated the effects of zingerone (a phenolic compound derived from spices) on UVB-induced cellular damage in KSCs. We found that zingerone significantly inhibited cellular senescence of KSCs in response to UVB irradiation. These effects were confirmed by the senescence-associated β-galactosidase and comet assays. Zingerone decreased the production of proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in UVB-irradiated KSCs. Moreover, UVB-induced expression of p21, a cell cycle arrest-related gene, was reduced by zingerone treatment, whereas zingerone upregulated the expression of proliferation-related genes such as proliferating cell nuclear antigen (PCNA) and vascular endothelial growth factor (VEGF), in addition to anti-senescence-related genes including telomerase reverse transcriptase (TERT), histone deacetylase 1 (HDAC1), and DNA (cytosine-5)-methyltransferase 1 (DNMT1). The UVB-protective effects of zingerone were mediated by inhibition of p42/44 MAPK and p38 MAPK. Therefore, zingerone could potentially be used to protect the epidermis from UVB-induced damage.