Amyloid Against Amyloid: Dimeric Amyloid Fragment Ameliorates Cognitive Impairments by Direct Clearance of Oligomers and Plaques.

Amyloid-ß (Aß) in the form of neurotoxic aggregates is regarded as the main pathological initiator and key therapeutic target of Alzheimer's disease. However, anti-Aß drug development has been impeded by the lack of a target needed for structure-based drug design and low permeability of the blood-brain barrier (BBB). An attractive therapeutic strategy is the development of amyloid-based anti-Aß peptidomimetics that exploit the self-assembling nature of Aß and penetrate the BBB. Herein, we designed a dimeric peptide drug candidate based on the N-terminal fragment of Aß, DAB, found to cross the BBB and solubilize Aß oligomers and fibrils. Administration of DAB reduced amyloid burden in 5XFAD mice, and downregulated neuroinflammation and prevented memory impairment in the Y-maze test. Peptide mapping assays and molecular docking studies were utilized to elucidate DAB-Aß interaction. To further understand the active regions of DAB, we assessed the dissociative activity of DAB with sequence modifications.

Lactobacillus plantarum-derived metabolites sensitize the tumor-suppressive effects of butyrate by regulating the functional expression of SMCT1 in 5-FU-resistant colorectal cancer cells.

A critical obstacle to the successful treatment of colorectal cancer (CRC) is chemoresistance. Chemoresistant CRC cells contribute to treatment failure by providing a mechanism of drug lethargy and modifying chemoresistance-associated molecules. The gut microbiota provide prophylactic and therapeutic effects by targeting CRC through anticancer mechanisms. Among them, Lactobacillus plantarum contributes to the health of the host and is clinically effective in treating CRC. This study confirmed that 5-fluorouracil (5-FU)-resistant CRC HCT116 (HCT116/5FUR) cells acquired butyrate-insensitive properties. To date, the relationship between 5-FU-resistant CRC and butyrate resistance has not been elucidated. Here, we demonstrated that the acquisition of butyrate resistance in HCT116/5FUR cells was strongly correlated with the inhibition of the expression and function of SMCT1, a major transporter of butyrate in colonocytes. L. plantarum-cultured cell-free supernatant (LP) restored the functional expression of SMCT1 in HCT116/5FUR cells, leading to butyrate-induced antiproliferative effect and apoptosis. These results suggest that LP has a synergistic effect on the SMCT1/butyrate-mediated tumor suppressor function and is a potential chemosensitizer to overcome dual 5-FU and butyrate resistance in HCT116 cells.

Aryloxypropanolamine targets amyloid aggregates and reverses Alzheimer-like phenotypes in Alzheimer mouse models.

BACKGROUND: Aggregated amyloid-ß (Aß) is considered a pathogenic initiator of Alzheimer's disease (AD), in strong association with tau hyperphosphorylation, neuroinflammation, synaptic dysfunction, and cognitive decline. As the removal of amyloid burden from AD patient brains by antibodies has shown therapeutic potential, the development of small molecule drugs inducing chemical dissociation and clearance of Aß is compelling as a therapeutic strategy. In this study, we synthesized and screened aryloxypropanolamine derivatives and identified 1-(3-(2,4-di-tert-pentylphenoxy)-2-hydroxypropyl)pyrrolidin-1-ium chloride, YIAD002, as a strong dissociator of Aß aggregates. METHODS: The dissociative activity of aryloxypropanolamine derivatives against Aß aggregates were evaluated through in vitro assays. Immunohistochemical staining, immunoblot assays, and the Morris water maze were used to assess the anti-Alzheimer potential in YIAD002-treated 5XFAD and transgenic APP/PS1 mice. Target-ligand interaction mechanism was characterized via a combination of peptide mapping, fluorescence dissociation assays, and constrained docking simulations. RESULTS: Among 11 aryloxypropanolamine derivatives, YIAD002 exerted strongest dissociative activity against ß-sheet-rich Aß aggregates. Upon oral administration, YIAD002 substantially reduced amyloid burden and accordingly, improved cognitive performance in the Morris water maze and attenuated major pathological hallmarks of AD including tauopathy, neuroinflammation, and synaptic protein loss. Mechanism studies suggest that YIAD002 interferes with intermolecular ß-sheet fibrillation by directly interacting with KLVFFA and IGLMVG domains of Aß. In addition, YIAD002 was found to possess dissociative activity against aggregates of pyroglutamate-modified Aß and tau. CONCLUSIONS: Collectively, our results evince the potential of chemical-driven dissociation of Aß aggregates by aryloxypropanolamines as a therapeutic modality of the amyloid clearance approach.

Highly Uniform Resistive Switching Performances Using Two-Dimensional Electron Gas at a Thin-Film Heterostructure for Conductive Bridge Random Access Memory.

This research demonstrates, for the first time, the development of highly uniform resistive switching devices with self-compliance current for conductive bridge random access memory using two-dimensional electron gas (2DEG) at the interface of an Al2O3/TiO2 thin-film heterostructure via atomic layer deposition (ALD). The cell is composed of Cu/Ti/Al2O3/TiO2, where Cu/Ti and Al2O3 overlayers are used as the active/buffer metals and solid electrolyte, respectively, and the 2DEG at the interface of Al2O3/TiO2 heterostructure, grown by the ALD process, is adopted as a bottom electrode. The Cu/Ti/Al2O3/TiO2 device shows reliable resistive switching characteristics with excellent uniformity under a repetitive voltage sweep (direct current sweep). Furthermore, it exhibits a cycle endurance over 107 cycles under short pulse switching. Remarkably, a reliable operation of multilevel data writing is realized up to 107 cycles. The data retention time is longer than 106 s at 85 °C. The uniform resistance switching characteristics are achieved via the formation of small (∼a few nm width) Cu filament with a short tunnel gap (<0.5 nm) owing to the 2DEG at the Al2O3/TiO2 interface. The performance and operation scheme of this device may be appropriate in neuromorphic applications.

Enhancement of interleukin-12 gene-based tumor immunotherapy by the reduced secretion of p40 subunit and the combination with farnesyltransferase inhibitor.

Interleukin-12 (IL-12) gene was shown to produce both IL-12 and p40 subunit. The excess production of the p40 subunit as a natural antagonist of IL-12 is a major obstacle of IL-12 gene-based cancer therapy. We previously reported that IL-12N220L gene, which selectively reduces the secretion of the p40 subunit, induces long-lasting stronger type 1 helper T cells (T(H)1) and cytotoxic T lymphocyte (CTL) immunity in hepatitis C virus (HCV) E2 DNA vaccination model and higher protection from challenge with tumor cells expressing E2 than IL-12 in a prophylactic setting. Here, we demonstrated that intratumoral injection of IL-12N220L-expressing adenovirus showed better tumor growth inhibition and higher survival rate than that of IL-12 or granulocyte macrophage-colony stimulating factor (GM-CSF)-expressing adenovirus in a therapeutic setting. In particular, the mice cured by IL-12N220L treatment were protected against intravenous rechallenge of the same tumor cells better than those by IL-12 treatment. In addition, the enhanced antitumor activity of IL-12N220L was confirmed in B16F10 lung metastasis model, which correlated with the frequency of tumor-specific interferon (IFN)-gamma-secreting cells. When tested in CT26/NP tumor that expresses influenza nucleoprotein (NP) as a tumor antigen, IL-12N220L induced stronger NP-specific T(H)1 and CTL responses than IL-12, particularly at a later time point, indicating the generating long-term tumor-specific memory T-cell responses. Moreover, the potent antitumor effects of IL-12N220L were further augmented by combination with chemotherapy using farnesyltransferase inhibitor (FTI), LB42908. Taken together, our results suggest that IL-12N220L is superior to IL-12 in cancer immunotherapy, which can be further enhanced by combination with chemotherapy.

Dioscorea Extract (DA-9801) Modulates Markers of Peripheral Neuropathy in Type 2 Diabetic db/db Mice.

The purpose of this study was to investigate the therapeutic effects of DA-9801, an optimized extract of Dioscorea species, on diabetic peripheral neuropathy in a type 2 diabetic animal model. In this study, db/db mice were treated with DA-9801 (30 and 100 mg/kg, daily, p.o.) for 12 weeks. DA-9801 reduced the blood glucose levels and increased the withdrawal latencies in hot plate tests. Moreover, it prevented nerve damage based on increased nerve conduction velocity and ultrastructural changes. Decrease of nerve growth factor (NGF) may have a detrimental effect on diabetic neuropathy. We previously reported NGF regulatory properties of the Dioscorea genus. In this study, DA-9801 induced NGF production in rat primary astrocytes. In addition, it increased NGF levels in the sciatic nerve and the plasma of type 2 diabetic animals. DA-9801 also increased neurite outgrowth and mRNA expression of Tieg1/Klf10, an NGF target gene, in PC12 cells. These results demonstrated the attenuation of diabetic peripheral neuropathy by oral treatment with DA-9801 via NGF regulation. DA-9801 is currently being evaluated in a phase II clinical study.

Enhanced immunogenicity and protective efficacy with the use of interleukin-12-encapsulated microspheres plus AS01B in tuberculosis subunit vaccination.

Tuberculosis subunit vaccines codelivered with interleukin-12 (IL-12)-encapsulated microspheres (IL-12EM) are designed for a sustained release of IL-12 and could induce strong Th1 immune responses specific to Ag85A and ESAT-6. The adjuvant combination of IL-12EM plus AS01B was a more efficient way to induce a sustained Th1 immunity and protection against Mycobacterium tuberculosis.