Protective effect of centipedegrass against Aß oligomerization and Aß-mediated cell death in PC12 cells.

CONTEXT: Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the abnormal accumulation of ß-amyloid (Aß). Multiple Aß-aggregated species have been identified, and neurotoxicity appears to be correlated with the amount of non-fibrillar oligomers. Potent inhibitors of Aß oligomer formation or Aß-induced cell toxicity have emerged as attractive means of therapeutic intervention. Eremochloa ophiuroide Hack. (Poaceae), also known as centipedegrass (CG), originates from China and South America and is reported to contain several C-glycosyl flavones and phenolic constituents. OBJECTIVE: We investigated whether CG could suppress Aß aggregation, BACE1 activity, and toxicity at neuronal cell. MATERIALS AND METHODS: The inhibitory effect of CG extracts toward aggregation of Aß42 was investigated in the absence and presence of 50 µg/mL CG. We investigated the inhibitory effects of CG (0-5 µg/mL) on BACE1 using fluorescence resonance energy transfer (FRET)-based assay. The effects of CG (0-75 µg/mL) on Aß42-induced neurotoxicity were examined in PC12 cells in the presence or absence of maysin and its derivatives of CG. RESULTS: We isolated EA-CG fraction (70% MeOH fraction from EtOAc extracts) from methanol extracts of CG, which contained approximately 60% maysin and its derivatives. In the present studies, we found that several Aß oligomeric forms such as the monomer, dimer, trimer, and highly aggregated oligomeric forms were remarkably inhibited in the presence of 50 µg/mL of EA-CG. EA-CG also inhibited BACE1 enzyme activity in a dose-dependent manner. EA-CG treatment generated approximately 50% or 85% inhibition to the control at the tested concentrations of 1 or 5 µg/mL, respectively. Moreover, the neurotoxicity induced by Aß42 was significantly reduced by treatment of EA-CG, and the 75 µg/mL EA-CG treatment significantly increased cell viability up to 82.5%. DISCUSSION AND CONCLUSION: These results suggested that the anti-Alzheimer's effects of CG occurred through inhibition of neuronal cell death by intervening with oligomeric Aß formation and reducing BACE1 activity. Maysin in CG could be an excellent therapeutic candidate for the prevention of AD.

Centipede grass exerts anti-adipogenic activity through inhibition of C/EBPß, C/EBPα, and PPARγ expression and the AKT signaling pathway in 3T3-L1 adipocytes.

BACKGROUND: Centipede grass (CG) originates from China and South America and is reported to contain several C-glycosyl flavones and phenolic constituents, including maysin and luteolin derivatives. This study aimed to investigate, for the first time, the antiobesity activity of CG and its potential molecular mechanism in 3T3-L1 cells. METHODS: To study the effect of CG on adipogenesis, differentiating 3T3-L1 cells were treated every day with CG at various concentrations (0-100 µg/ml) for six days. Oil-red O staining and triglyceride content assay were performed to determine the lipid accumulation in 3T3-L1 cells. The expression of mRNAs or proteins associated with adipogenesis was measured using RT-PCR and Western blotting analysis. We examined the effect of CG on level of phosphorylated Akt in 3T3-L1 cells treated with CG at various concentration s during adipocyte differentiation. RESULTS: Differentiation was investigated with an Oil-red O staining assay using CG-treated 3T3-L1 adipocytes. We found that CG suppressed lipid droplet formation and adipocyte differentiation in 3T3-L1 cells in a dose-dependent manner. Treatment of the 3T3-L1 adipocytes with CG resulted in an attenuation of the expression of adipogenesis-related factors and lipid metabolic genes. The expression of C/EBPα and PPARγ, the central transcriptional regulators of adipogenesis, was decreased by the treatment with CG. The expression of genes involved in lipid metabolism, aP2 were significantly inhibited following the CG treatment. Moreover, the CG treatment down-regulated the phosphorylation levels of Akt and GSK3ß. CONCLUSIONS: Taken collectively, these data indicated that CG exerts antiadipogenic activity by inhibiting the expression of C/EBPß, C/EBPα, and PPARγ and the Akt signaling pathway in 3T3-L1 adipocytes.

Thymic Hematoma Found in a Wild Eurasian Otter (Lutra lutra).

Thymic hematomas are uncommon in animals, and the few reported cases are all in dogs. In May 2019, we necropsied a wild Eurasian otter (Lutra lutra) in Junju, Republic of Korea, and found a thymic hematoma without any signs of trauma or hemorrhage in other organs, except for a hemothorax. This study describes the macroscopic and microscopic examinations of a thymic hematoma in an Eurasian otter.

Linear Micro-patterned Drug Eluting Balloon (LMDEB) for Enhanced Endovascular Drug Delivery.

In-stent restenosis (ISR) often occurs after applying drug eluting stents to the blood vessels suffering from atherosclerosis or thrombosis. For treatment of ISR, drug eluting balloons (DEB) have been developed to deliver anti-proliferative drugs to the lesions with ISR. However, there are still limitations of DEB such as low drug delivery efficiency and drug loss to blood flow. Although most researches have focused on alteration of drug formulation for more efficient drug delivery, there are few studies that have attempted to understand and utilize the contact modality of DEB drug delivery. Here, we developed a linear micro-patterned DEB (LMDEB) that applied higher contact pressure to enhance drug stamping to vascular tissue. Ex vivo and in vivo studies confirmed that higher contact pressure from micro-patterns increased the amount of drug delivered to the deeper regions of vessel. Finite element method simulation also showed significant increase of contact pressure between endothelium and micro-patterns. Quantitative analysis by high performance liquid chromatography indicated that LMDEBs delivered 2.3 times higher amount of drug to vascular tissue in vivo than conventional DEBs. Finally, efficacy studies using both atherosclerotic and ISR models demonstrated superior patency of diseased vessels treated with LMDEB compared to those treated with DEB.

Maysin and Its Flavonoid Derivative from Centipedegrass Attenuates Amyloid Plaques by Inducting Humoral Immune Response with Th2 Skewed Cytokine Response in the Tg (APPswe, PS1dE9) Alzheimer's Mouse Model.

Alzheimer's disease (AD) is a slow, progressive neurodegenerative disease and the most common type of dementia in the elderly. The etiology of AD and its underlying mechanism are still not clear. In a previous study, we found that an ethyl acetate extract of Centipedegrass (CG) (i.e., EA-CG) contained 4 types of Maysin derivatives, including Luteolin, Isoorientin, Rhamnosylisoorientin, and Derhamnosylmaysin, and showed protective effects against Amyloid beta (Aß) by inhibiting oligomeric Aß in cellular and in vitro models. Here, we examined the preventative effects of EA-CG treatment on the Aß burden in the Tg (Mo/Hu APPswe PS1dE9) AD mouse model. We have investigated the EA-CG efficacy as novel anti-AD likely preventing amyloid plaques using immunofluorescence staining to visually analyze Aß40/42 and fibril formation with Thioflavin-S or 6E10 which are the profile of immunoreactivity against epitope Aß1-16 or neuritic plaque, the quantitation of humoral immune response against Aß, and the inflammatory cytokine responses (Th1 and Th2) using ELISA and QRT-PCR. To minimize the toxicity of the extracted CG, we addressed the liver toxicity in response to the CG extract treatment in Tg mice using relevant markers, such as aspartate aminotransferase (AST)/ alanine aminotransferase (ALT) measurements in serum. The EA-CG extract significantly reduced the Aß burden, the concentration of soluble Aß40/42 protein, and fibril formation in the hippocampus and cortex of the Tg mice treated with EA-CG (50 mg/kg BW/day) for 6 months compared with the Tg mice treated with a normal diet. Additionally, the profile of anti-inflammatory cytokines revealed that the levels of Th2 (interleukin-4 (IL-4) and interleukin-10 (IL-10)) cytokines are more significantly increased than Th1 (interferon-γ (IFN-γ), interleukin-2(IL-2)) in the sera. These results suggest that the EA-CG fraction induces IL-4/IL-10-dependent anti-inflammatory cytokines (Th2) rather than pro-inflammatory cytokines (Th1), which are driven by IL-2/IFN-γ. With regard to the immune response, EA-CG induced an immunoglobulin IgG and IgM response against the EA-CG treatment in the Tg mice. Furthermore, EA-CG significantly ameliorated the level of soluble Aß42 and Aß40. Similarly, we observed that the fibril formation was also decreased by EA-CG treatment in the hippocampus and cortex after quantitative analysis with Thioflavin-S staining in the Tg brain tissues. Taken together, our findings suggested that Maysin and its derivative flavonoid compounds in the EA-CG fraction might be beneficial therapeutic treatments or alternative preventative measures to adjuvant for boosting humoral and cellular include immune response and anti-inflammation which may lead to amyloid plaque accumulation in Alzheimer's patients' brains.

Mycobacterium bovis infection in a wild sow (Sus scrofa): first case in Korea.

Mycobacterium (M.) bovis causes tuberculosis and has a broad host range, including humans, livestock, and wild animals. M. bovis infection of wild boar has been reported in several European countries. We report here the first case of M. bovis infection in a domesticated wild sow in Korea. Granulomatous and necrotizing lesions with small numbers of acid-fast bacilli were observed in nodules of the lung of wild sow. Furthermore, the M. bovis isolate from the wild sow had spoligotype SB0140 and a novel MIRU-VNTR allelic profile, which is not found in cattle and deer in Korea.

Determination of enantiomeric compositions of DOPA by tandem mass spectrometry using the kinetic method with fixed ligands.

A fixed ligand (FL) version of the kinetic method was applied to rapid, simple, and accurate chiral analysis of DOPA, which is an important drug used for treatment of Parkinson's disease. Singly charged clusters containing the transition metal ion Cu(II), pyridyl ligands which serve as a fixed ligand, some amino acid as a reference, and the analyte DOPA were generated by electrospray ionization. The cluster ion of interest was mass-selected, and the kinetics of its competitive unimolecular dissociations was investigated in an ion trap mass spectrometer. The chiral selectivity (R(chiral)), the ratio of the two fragment ion abundances when the cluster contains one pure enantiomer of the analyte expressed relative to that for the other enantiomer, varies with fixed ligands, references, and transition metals. Chiral discrimination was optimized in 1,10-phenanthroline as a FL, L-Phe and L-Pro as a reference, and Cu(II) as a central metal ion. Quantitative determinations of the enantiomeric composition of DOPA were achieved using two-point calibration curves. The linear relationship between the logarithm of the fragment ion abundance ratio (ln R) and enantiomeric compositions (ee%) of the DOPA allows the determination of the chiral purity of enantiomeric mixtures.

Enantioselective resolution of thyroxine hormone by high-performance liquid chromatography utilizing a highly fluorescent chiral tagging reagent.

A highly fluorescent chiral tagging reagent, 4-(3-isothiocyanatopyrrolidin-1-yl)-7-(N,N-dimethylaminosulfonyl-2,1,3-benzoxadiazole, [R(-)-DBD-PyNCS], was employed to develop an indirect resolution method for efficient separation of thyroxine enantiomers,D-T(4) and L-T(4). The reaction of R(-)-DBD-PyNCS with the thyroxine enantiomers proceeds effectively at 40 degrees C for 20 min in the presence of basic medium to produce the corresponding pair of diastereomers. No racemization occurs during the tagging reaction under the optimized conditions. Various experimental parameters for derivatization reaction including the species of catalyst, the concentration of tagging reagent and reaction temperatures, have been examined to get a highest yield for T(4) derivatives. The structure of T(4) derivatives was identified based on ESI-MS/MS measurements in negative mode. The efficient separation of D-, L-T(4) derivatives was achieved by isocratic elution with water-acetonitrile mobile phase containing 1% AcOH on a reversed phase column utilizing a conventional fluorescence detector. The resolution (Rs) value of the diastereomers derived from thyroxine was 5.1. The calibration curves of both the D-T(4) and L-T(4) were linear over the concentration range of 0.1-20 microg/ml. The limits of detection (S/N = 3) for both D-T(4) and L-T(4) were 0.2 ng per injection. The proposed method was applied to the determination of D-T(4) and L-T(4) in pharmaceutical formulations and human serum samples.