Se-Gun Kim

Chestnut honey has various benefits, such as antioxidative, anti-inflammatory, immunomodulatory, antibacterial, and antiviral effects. However, the effects of chestnut honey or the ethyl acetate fraction of chestnut honey (EACH) on neurodegenerative diseases and their related cognitive impairment and neurotoxicity have not yet been established. Therefore, in this study, we investigated the mitigating effect of the EACH on scopolamine (SCO)-injected cognitive decline in mice and glutamate-exposed neurotoxicity in HT22 cells. EACH administration significantly reversed SCO-induced cognitive decline in mice, as demonstrated through the Morris water maze and passive avoidance tests. The EACH treatment showed a significant alleviation effect by recovering more than 80% of the cell viability decrease induced by glutamate exposure in the HT22 neuronal cell model. Furthermore, the EACH significantly reduced reactive oxygen species accumulation, lactate dehydrogenase release, mitochondrial depolarization, and neuronal apoptosis. The EACH regulated the level of apoptosis-related proteins, induced the nuclear translocation of nuclear factor-E2-related factor 2 (Nrf-2) and the expression of related antioxidant proteins, and induced the phosphorylation of tropomyosin-related kinase receptor B (TrkB)/cAMP-calcium response element-binding protein (CREB) and the expression of brain-derived neurotrophic factor. These data indicate that the EACH can prevent neurons from oxidative damage and improve cognitive dysfunction by activating Nrf-2 and TrkB/CREB signaling pathways. Therefore, the EACH demonstrates potential therapeutic value in mitigating oxidative stress-induced neurotoxicity, cognitive decline, and related neurodegenerative diseases.

Herpes simplex virus 1 (HSV-1) is double-stranded DNA virus that belongs to the Orthoherpesviridae family. It causes serious neurological diseases of the central nervous system, such as encephalitis. The current U.S. Food and Drug Administration (FDA)-approved drugs for preventing HSV-1 infection include acyclovir (ACV) and valacyclovir; however, their long-term use causes severe side effects and often results in the emergence of drug-resistant strains. Therefore, it is important to discover new antiviral agents that are safe and effective against HSV-1 infection. Korean chestnut honey (KCH) has various pharmacological activities, such as antioxidant, antibacterial, and anti-inflammation effects; however, antiviral effects against HSV-1 have not yet been reported. Therefore, we determined the antiviral activity and mechanism of action of KCH after HSV-1 infection on the cellular level. KCH inhibited the HSV-1 infection of host cells through binding and virucidal steps. KCH decreased the production of reactive oxygen species (ROS) and calcium (Ca²⁺) following HSV-1 infection and suppressed the production of inflammatory cytokines by inhibiting nuclear factor kappa-light-chain-enhancer of activated B cells (NF-кB) activity. Furthermore, we found that KCH inhibited the expression of the nod-like receptor protein 3 (NLRP3) inflammasome during HSV-1 infection. Taken together, the antiviral effects of KCH occur through multiple targets, including the inhibition of viral replication and the ROS-mediated NLRP3 inflammasome pathway. Our findings suggest that KCH has potential for the treatment of HSV-1 infection and related diseases.

Propolis has been used by humans as a nutraceutical agent with therapeutic benefits for many centuries. The chemical composition and biological activities of propolis depend on its botanical and geographical origins. The aim of this study was to characterize Korean propolis by quantitating their chrysin content using an ultra high performance liquid chromatography (UPLC). Methanol extracts of propolis were comprehensively analyzed by UPLC for the isolation and quantification of chrysin in propolis from different origins. The reproducibility of the method was 1.9% to 6.0%, and accuracy was confirmed with average recovery ranging from 98.2% to 101.0%. The chrysin content in propolis samples was successfully determined within 13.299 min. All propolis samples, except those from Jeju Island, contained chrysin. There were some variations in the concentration of chrysin among propolis samples from different locations. The chrysin of the analyzed propolis samples confirmed their affiliation to the Korean propolis except those from Jeju Island, and the proposed UPLC method yielded good sensitivity, linearity, repeatability, and accuracy.

Background. Currently, obesity and its comorbidities have become a serious threat to human health necessitating urgent development of safe and effective therapy for their management. Materials and Methods. In this research, a novel polyherbal formulation (F2) was prepared by mixing specific proportions of royal jelly and lemon juice with ethanol extracts of Orostachys japonicus, Rhus verniciflua, and Geranium thunbergii. The antioxidant activity was assessed using DPPH and ABTS assay methods. The antiobesity potential of the F2 was assessed in vitro using 3T3-L1 fibroblast and in vivo using a high-fat diet (HFD) fed C57BL/6J mice model. F2 was administered in mice at the dose of 23mg/kg and 46mg/kg, twice daily by oral gavage. A well-accepted antiobesity agent, Garcinia cambogia (GC), at 200mg/kg was used as a positive control. Results. F2 was observed to exhibit synergistic antiadipogenic activity in 3T3-L1 cells. This inhibition was reinforced by the downregulation of specific adipogenic transcription factors. Furthermore, F2 was also found to reduce mice body weight gain, food efficiency ratio, fasting blood glucose level, fat deposition into the liver, and mass of white adipose tissue. F2 also played a role in the excretion of fat consumed by the mice. For most of the assays performed, the F2 (46mg/kg) was comparable to the positive control GC (200mg/kg). In addition, potential and synergistic antioxidant activity was observed on F2. Conclusion. The results revealed that the formulation F2 exhibited potential antiobesity activity through the inhibition of adipocyte differentiation, dietary fat absorption, and reduction of free fatty acids deposition in tissues.

Angiopteris helferiana C.Presl is a gigantic fleshy-type fern, belonging to Marattiaceae family. In previous study, we reported the potent anti-adipogenic and anti-inflammatory activities of ethylacetate (EtOAc) and n-butanol (BuOH) fractions of methanol extract of rhizomes of A. helferiana. In continuation, in this study, we report the isolation, characterization, and bioactivity analysis of principle bioactive compounds in these fractions. (−)-epi-Osmundalactone (1) and angiopteroside (2) were isolated from EtOAc and BuOH fractions, respectively. The structures of these compounds were established on the basis of NMR spectroscopic data. The quantification study using UPLC revealed the contents of compounds 1 and 2 in the dried rhizome to be 1.54% and 3.2%, respectively. These compounds were evaluated for their anti-adipogenic and anti-inflammatory activities using 3T3-L1 and RAW 264.7 cells, respectively. Compound 1 (2.5 µg/mL) and 2 (20 µg/mL) inhibited the lipid production by 35% and 25%, respectively. Regarding the anti-inflammatory activity, compound 1 (5 µg/mL) inhibited the nitrite production by nearly 82%. In conclusion, the presence of potent anti-adipogenic and anti-inflammatory compounds in A. helferiana indicate its potential role in the use of herb-based treatment for obesity and other related diseases.

Bee venom (BV) has long been used as a traditional medicine. The aim of the present study was to formulate a BV emulsion with good rheological properties for dermal application and investigate the effect of formulation on the permeation of melittin through dermatomed rat skin. A formulated emulsion containing 1% (w/v) BV was prepared. The emulsion was compared with distilled water (DW) and 25% (w/v) N-methyl-2-pyrrolidone (NMP) in DW. Permeation of melittin from aqueous solution through the dermatomed murine skin was evaluated using the Franz diffusion cells. Samples of receptor cells withdrawn at pre-determined time intervals were measured for melittin amount. After the permeation study, the same skin was used for melittin extraction. In addition, a known amount of melittin (5 μg/mL) was added to stratum corneum, epidermis, and dermis of the rat skin, and the amount of melittin was measured at pre-determined time points. The measurement of melittin from all samples was done with HPLC-MS/MS. No melittin was detected in the receptor phase at all time points in emulsion, DW, or NMP groups. When the amount of melittin was further analyzed in stratum corneum, epidermis, and dermis from the permeation study, melittin was still not detected. In an additional experiment, the amount of melittin added to all skin matrices was corrected against the amount of melittin recovered. While the total amount of melittin was retained in the stratum corneum, less than 10% of melittin remained in epidermis and dermis within 15 and 30 min, respectively. Skin microporation with BV emulsion facilitates the penetration of melittin across the stratum corneum into epidermis and dermis, where emulsified melittin could have been metabolized by locally-occurring enzymes.

Propolis is a resinous substance collected by honeybees to seal honeycomb, which has been used with broad clinical applications. The chemical characteristics of propolis are linked to the diversity of geographical location, plant sources and bee species. The aim of this study was to characterize Korean propolis components and quantifying their component content by ultra-performance liquid chromatography (UPLC). Methanol extracts of propolis were comprehensively analysed by UPLC for the isolation and quantification of pinocembrin in propolis of different geographic. All of the propolis samples, except that from Jeju island, contained pinocembrin. Concentration of pinocembrin ranged between the 11.0~38.1㎎/g. Concentration of pinocembrin showed some variation among the propolis samples from different origins. The pinocembrin of the analysed propolis samples confirm its affiliation to the Korean propolis.

Methicillin-resistant Staphylococcus aureus (MRSA), along with other antibiotic resistant bacteria, has become a significant social and clinical problem. There is thus an urgent need to develop naturally bioactive compounds as alternatives to the few antibiotics that remain effective. Here we assessed the in vitro activities of bee venom (BV), alone or in combination with ampicillin, penicillin, gentamicin or vancomycin, on growth of MRSA strains. The antimicrobial activity of BV against MRSA strains was investigated using minimum inhibitory concentrations (MIC), minimum bactericidal concentrations (MBC) and a time-kill assay. Expression of atl which encodes murein hydrolase, a peptidoglycan-degrading enzyme involved in cell separation, was measured by reverse transcription-polymerase chain reaction. The MICs of BV were 0.085 µg/mL and 0.11 µg/mL against MRSA CCARM 3366 and MRSA CCARM 3708, respectively. The MBC of BV against MRSA 3366 was 0.106 µg/mL and that against MRSA 3708 was 0.14 µg/mL. The bactericidal activity of BV corresponded to a decrease of at least 3 log CFU/g cells. The combination of BV with ampicillin or penicillin yielded an inhibitory concentration index ranging from 0.631 to 1.002, indicating a partial and indifferent synergistic effect. Compared to ampicillin or penicillin, both MRSA strains were more susceptible to the combination of BV with gentamicin or vancomycin. The expression of atl gene was increased in MRSA 3366 treated with BV. These results suggest that BV exhibited antibacterial activity and antibiotic-enhancing effects against MRSA strains. The atl gene was increased in MRSA exposed to BV, suggesting that cell division was interrupted. BV warrants further investigation as a natural antimicrobial agent and synergist of antibiotic activity.