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1.
Chemistry ; : e202402564, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39278823

ABSTRACT

A photoinduced copper-catalyzed enantioselective conjugate addition of acylsilanes has been developed. The conjugate acylation of α,ß-unsaturated ketones and aldehydes was promoted by a copper(I)/chiral NHC catalyst under visible-light irradiation for synthesizing various 2-substituted 1,4-dicarbonyl compounds in enantioenriched forms. Mechanistic studies combining experiments and quantum chemical calculations indicated a reaction mechanism involving copper-to-acyl charge transfer (i.e., metal-to-ligand charge transfer (MLCT)) excitation of an alkene-bound acylcopper complex. The MLCT excitation is followed by an electronical and geometrical change to generate a ß-radical-C-enolate-Cu(II)-acyl complex with an acyl radical character, which undergoes facile C-C bond formation in the copper coordination sphere, affording the 1,4-conjugate addition product.

2.
J Org Chem ; 89(19): 13913-13922, 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39292972

ABSTRACT

The mechanism of the aza-aldol reaction between boron aza-enolate and benzaldehyde is investigated by using density functional theory calculations. The result shows that the syn-E isomer is preferentially formed, consistent with experimental observations. The six-membered ring transition state (TS) with the boat form leads to the E isomer, while the more unstable chair TS does to the Z isomer. The preference of the syn isomer is determined by the interactions between the substituents of aza-enolate and benzaldehyde. Structural distortion and intrinsic reaction coordinate analyses of simplified model systems provide insights into the origin of the relative stability of the rate-determining TS with boat and chair forms. The boat TS is an early TS; thus, minimal structural distortions of the reactant are required to reach this TS. The Lewis pair interactions between the boron and imine groups during B-N elimination also influenced the relative stability of the TSs. This interaction involves the nitrogen lone pair in the boat TS, while the π(N═C) orbital is involved in the chair TS. The Lewis pair with the lone pair stabilizes the TS more than that with the π orbital. The boron aza-enolate with 9-BBN generates an ate complex and forms C-C bonds sequentially, whereas that with Bpin does not generate an ate complex and exhibits the concerted formation of B-O and C-C bonds. Thus, the higher electrophilicity of boron such as 9-BBN enhances the reactivity by facilitating the formation of the ate complex. A reaction design is proposed to reverse the syn/anti selectivity. Proof-of-concept DFT calculations suggested that the modification of the imine group would change the relative stability of the boat/chair TSs and give the anti-product.

3.
J Biochem ; 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39271134

ABSTRACT

Phosphoinositides (PIPs) are phospholipids and components of the cellular membrane. In mammals, seven phosphorylated derivatives of PIPs have been identified. Among them, phosphatidylinositol 3,4-bisphosphate [PI(3,4)P2] is produced by lipid phosphatases (e.g., SHIP2) or by lipid kinases PI3KC2α and PI3KC2ß. Although PI(3,4)P2 is undetectable in normal mouse or human tissues and common cell lines, it appears in a mouse prostate cancer model and in cells exposed to oxidative stress, indicating that PI(3,4)P2 is involved in the pathogenesis of some diseases. Here, I summarize recent findings on the cellular roles and pathophysiological significance of PI(3,4)P2.

5.
Mod Rheumatol ; 2024 Aug 29.
Article in English | MEDLINE | ID: mdl-39206863

ABSTRACT

OBJECTIVES: This retrospective study aimed to examine the clinical features of juvenile onset ankylosing spondylitis (JoAS) in Japanese patients. METHODS: We examined clinical symptoms (including initial symptoms) and the progression to diagnosis of AS in 17 Japanese JoAS patients at our institute between January 2004 and May 2023. Initial symptoms were considered pain at axial joints and/or extra-axial joints. RESULTS: Mean ages (± standard deviation) at onset and diagnosis of AS were 12.9 (± 2.0) years and 19.6 (± 9.6) years, respectively. The back was the most common site of initial symptoms (seven patients; 41.2%), followed by the hip (five patients; 29.4%) and knees (five patients; 29.4%). Initial symptoms were limited to extra-axial joints and axial joints in nine (52.9%) and seven (41.2%) patients, respectively. Nine patients (52.9%) were recognised as a musculoskeletal disease other than AS, such as oligoarticular juvenile idiopathic arthritis. CONCLUSIONS: Sites of initial symptoms were frequently the back, hip, and knees, with 52.9% of patients having initial symptoms limited to extra-axial joints. More than half of the patients were recognised musculoskeletal diseases other than AS.

6.
J Am Chem Soc ; 146(33): 22993-23003, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39110536

ABSTRACT

Metal nanoclusters (NCs) have unique properties because of their small size, which makes them useful as catalysts in reactions like cross-coupling. Pd-catalyzed oxidative amination, which involves dehydrogenative C-N bond formation, uses Pd complexes as the active species. It is known that the catalytic conditions involve the formation of Pd(0) species from Pd NCs, but the precise role of Pd NCs in the transformations has not been established. In this study, we investigated the characteristic properties of Pd NCs in oxidative amination of 1,3-dienes. The reaction achieved direct amination of commercially accessible 1,3-dienes with secondary aromatic amines, providing a variety of nitrogen containing 1,3-dienes. The compound was applicable to radical polymerization to provide the nitrogen-fabricated 1,3-diene-based polymer, which exhibited a different thermal stability compared to aliphatic nitrogen-fabricated diene polymers. In addition to the synthetic utility, by combining X-ray absorption fine structure and small-angle X-ray scattering analysis, we revealed amines and 1,3-dienes affected metal leaching from the Pd nanoparticles and stabilization of Pd NCs in the catalytic reaction. Additionally, DFT calculation suggested that the catalytic intermediate contained multiple adjacent Pd atoms and was responsible for formation of an σ-allylic intermediate that is difficult to form with the use of Pd complexes. These results could be used to understand the underlying phenomenon in the oxidative coupling reaction and develop Pd NCs-based dehydrogenation.

7.
Mod Rheumatol ; 2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39177377

ABSTRACT

BACKGROUND: This study aimed to investigate the prevalence of social frailty and associated factors. METHODS: A total of 655 consecutive patients who were able to complete the Kihon Checklist (KCL) and the Questionnaire on Social Frailty between June and August 2022 were enrolled. Social frailty was assessed using the Makizako Social Frailty Index. Patient characteristics were analyzed by analysis of variance. Factors associated with social frailty were analyzed using multivariate logistic analysis. Spearman's rank correlation coefficients were used to examine correlations between each KCL domain and social frailty. RESULTS: Mean age was 68 years, and disease duration was 12 years; 73% of patients were female. Social frailty was present in 30.8% of patients, with 36.5% classified as social pre-frailty. Multivariate analysis revealed age and HAQ-DI to be independent factors associated with social frailty. The proportion of social frailty increased with increasing age and worsening HAQ-DI scores. The KCL domain "Isolation" was the most strongly associated with social frailty (r = 0.601, P < 0.001), with higher scores associated with a higher proportion of social frailty. CONCLUSIONS: Social frailty in RA patients is associated with age and physical impairment (HAQ-DI). Moreover, the KCL domain "Isolation" was strongly associated with social frailty.

8.
Life Sci Alliance ; 7(9)2024 Sep.
Article in English | MEDLINE | ID: mdl-38906678

ABSTRACT

H3.1 histone is predominantly synthesized and enters the nucleus during the G1/S phase of the cell cycle, as a new component of duplicating nucleosomes. Here, we found that p53 is necessary to secure the normal behavior and modification of H3.1 in the nucleus during the G1/S phase, in which p53 increases C-terminal domain nuclear envelope phosphatase 1 (CTDNEP1) levels and decreases enhancer of zeste homolog 2 (EZH2) levels in the H3.1 interactome. In the absence of p53, H3.1 molecules tended to be tethered at or near the nuclear envelope (NE), where they were predominantly trimethylated at lysine 27 (H3K27me3) by EZH2, without forming nucleosomes. This accumulation was likely caused by the high affinity of H3.1 toward phosphatidic acid (PA). p53 reduced nuclear PA levels by increasing levels of CTDNEP1, which activates lipin to convert PA into diacylglycerol. We moreover found that the cytosolic H3 chaperone HSC70 attenuates the H3.1-PA interaction, and our molecular imaging analyses suggested that H3.1 may be anchored around the NE after their nuclear entry. Our results expand our knowledge of p53 function in regulation of the nuclear behavior of H3.1 during the G1/S phase, in which p53 may primarily target nuclear PA and EZH2.


Subject(s)
Cell Nucleus , Enhancer of Zeste Homolog 2 Protein , Histones , Tumor Suppressor Protein p53 , Histones/metabolism , Tumor Suppressor Protein p53/metabolism , Cell Nucleus/metabolism , Humans , Enhancer of Zeste Homolog 2 Protein/metabolism , G1 Phase , S Phase , Nuclear Envelope/metabolism , Methylation , Animals , Nucleosomes/metabolism
9.
Phys Chem Chem Phys ; 26(27): 18530-18537, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38869073

ABSTRACT

As the sizes of noble metal catalysts, such as platinum, have been successfully minimized, fundamental insights into the electronic properties of metal sub-nanoclusters are increasingly sought for optimizing their catalytic performance. However, it is difficult to rationalize the catalytic activities of metal sub-nanoclusters owing to their more complex electronic structure compared with those of small molecules and bulky solids. In this study, the adsorption of molecular oxygen on a Pt13 sub-nanocluster supported on a graphene layer was analyzed using density functional theory. Unlike bulk Pt, the Pt13 sub-nanocluster has multiple adsorption sites, and the adsorption energy depends strongly on the type of adsorption site. The O2 adsorption energy does not correlate with the transferred charge between O2 and the Pt13 moiety; therefore, to elucidate the differences in the adsorption sites, we propose an original approach for analyzing the electronic structure change in metal sub-nanoclusters caused by molecular adsorption. Our analysis of the integrated local density of state (LDOS) revealed that O2 adsorption on the Pt13 sub-nanocluster has a distinct feature, different from that on a smaller Pt2 cluster or rather a larger Pt slab. The change in the electronic structure of the Pt13 moiety was primarily observed near the Fermi level, different from that of the Pt slab whose DOS was distributed over a wide energy range. Furthermore, the change in the integrated LDOS correlated well with the O2 adsorption energy on the Pt13 sub-nanocluster.

10.
Mod Rheumatol ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38727542

ABSTRACT

OBJECTIVES: The present study aimed to examine discrepancies between assessments based on Routine Assessment of Patient Index Data 3 (RAPID3) and Simple Disease Activity Index (SDAI) in RA patients with controlled disease activity. METHODS: Data from 464 RA patients in SDAI remission or low disease activity (REM/LDA) were analyzed. Patient-reported outcome (PRO) measures, including Health Assessment Questionnaire Disability Index (HAQ-DI), 25-question Geriatric Locomotive Function Scale (GLFS-25), and Kihon checklist (KCL), were assessed. Logistic regression models were used to identify factors associated with RAPID3 moderate or high disease activity (MDA/HDA). Cutoff values of RAPID3 MDA/HDA for each PRO evaluation item were determined using receiver operating characteristic curve analysis. RESULTS: Among RA patients in SDAI REM/LDA, 84.9% were in RAPID3 REM/LDA. Multivariable analysis revealed that HAQ-DI, GLFS-25, and KCL were independently associated with RAPID3 MDA/HDA. Subdomain analysis of KCL revealed that activities of daily living, physical function, cognitive function, and depressive mood were significantly associated with RAPID3 MDA/HDA. Cutoff values for HAQ-DI and KCL were 0.38 and 8, respectively. CONCLUSIONS: In RA patients with controlled disease activity, discrepancies between RAPID3 and SDAI assessments were observed, with factors such as HAQ-DI, GLFS-25, and KCL being independently associated with RAPID3 MDA/HDA.

11.
JACS Au ; 4(3): 1048-1058, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38559712

ABSTRACT

During the hydrogenation of CO2 to methanol over mixed-oxide catalysts, the strong adsorption of CO2 and formate poses a barrier for H2 dissociation, limiting methanol selectivity and productivity. Here we show that by using Co-containing dual-atom oxide catalysts, the poisoning effect can be countered by separating the site for H2 dissociation and the adsorption of intermediates. We synthesized a Co- and In-doped ZrO2 catalyst (Co-In-ZrO2) containing atomically dispersed Co and In species. Catalyst characterization showed that Co and In atoms were atomically dispersed and were in proximity to each other owing to a random distribution. During the CO2 hydrogenation reaction, the Co atom was responsible for the adsorption of CO2 and formate species, while the nearby In atoms promoted the hydrogenation of adsorbed intermediates. The cooperative effect increased the methanol selectivity to 86% over the dual-atom catalyst, and methanol productivity increased 2-fold in comparison to single-atom catalysts. This cooperative effect was extended to Co-Zn and Co-Ga doped ZrO2 catalysts. This work presents a different approach to designing mixed-oxide catalysts for CO2 hydrogenation based on the preferential adsorption of substrates and intermediates instead of promoting H2 dissociation to mitigate the poisonous effects of substrates and intermediates.

12.
Int J Rheum Dis ; 27(1): e15034, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38287545

ABSTRACT

OBJECTIVE: This study aimed to determine whether there are associations between laughter, disease activity, frailty, and depression in rheumatoid arthritis (RA) patients. METHODS: A total of 240 patients were included in this prospective cohort study on frailty in RA patients between March 2021 and June 2022. Patients were divided into the following four groups according to the frequency of laughter: "almost every day," "1-5 days per week," "1-3 days per month," and "never or almost never." Patient characteristics were compared among the four groups by analysis of variance. Factors associated with laughter were identified by multivariable logistic analysis. RESULTS: The mean 28-joint Disease Activity Score using CRP was 1.91, with 70.7% of patients in remission and 12.6% in low disease activity. For the "almost every day" (42.5% of patients), "1-5 days per week" (40.0%), "1-3 days per month" (11.3%), and "never or almost never" (6.3%) groups, scores of the Kihon Checklist (KCL) for assessing frailty status were 3.5, 4.6, 7.3, and 8.1 (p < .001), respectively, and scores of the Beck Depression Inventory (BDI-II) were 8.4, 10.7, 15.1, and 16.5 (p < .001), respectively. Multivariable analysis revealed that KCL (OR: 0.81, 95% CI: 0.73-0.90) and BDI-II (OR: 0.91, 95% CI: 0.86-0.95) scores were independently associated with the frequency of laughter. CONCLUSION: Frailty and depression were associated with laughter in RA patients with controlled disease activity. Interventions aimed at not only disease activity control but also frailty prevention may lead to a life filled with laughter.


Subject(s)
Arthritis, Rheumatoid , Frailty , Laughter , Humans , Depression/diagnosis , Depression/epidemiology , Depression/etiology , Frailty/diagnosis , Frailty/epidemiology , Prospective Studies , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/epidemiology
13.
J Phys Chem A ; 128(1): 81-88, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38113234

ABSTRACT

Single molecule magnets (SMMs) have been a promising material for next-generation high-density information storage and molecular spintronics. N23--bridged dilanthanide complexes, {[(Me3Si)2N]2Ln(THF)(µ-η2:η2-N2)(THF)Ln[(Me3Si)2N]2}1-, exhibit high blocking temperatures and have been one of the promising candidates for future application. Rational understanding should be established between the magnetic properties and electronic structure. However, the theoretical study is still challenging due to the complexities in their electronic structures. Here, we theoretically studied the magnetic susceptibility of dilanthanide SMMs based on the state-of-the-art multistate-complete active space self-consistent field and perturbation theory at the second order and restricted active space state interaction with spin-orbit coupling calculations. Temperature dependence of the magnetic susceptibility (χmT-T curve) was quantitatively reproduced by the theoretical calculations. The complexities in the electronic states of these dilanthanide complexes originate from significantly strong static electron correlations in the lanthanide 4f and N2 π* orbitals and the SOC effect. The temperature dependence of the magnetic susceptibility results from the energy levels and magnetic properties of the low-lying excited state. The χmT values below 50 K are dominated by the ground state, while thermal distribution in the low-lying excited state affects the χmT values over 50 K. Saturation magnetization at low temperatures was also evaluated, and the result agrees with the experimental observation.

14.
Chem Sci ; 14(47): 13908-13914, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38075668

ABSTRACT

Surface intermediate species and oxygen vacancy-assisted mechanism over CeO2 catalyst in the direct dimethyl carbonate (DMC) synthesis from carbon dioxide and methanol are suggested by means of transient spectroscopic methodologies in conjunction with multivariate spectral analysis. How the two reactants, i.e. CO2 and methanol, interact with the CeO2 surface and how they form decisive surface intermediates leading to DMC are unraveled by DFT-based molecular dynamics simulation by precise statistical sampling of various configurations of surface states and intermediates. The atomistic simulations and uncovered stability of different intermediate states perfectly explain the unique DMC formation profile experimentally observed upon transient operations, strongly supporting the proposed oxygen vacancy-assisted reaction mechanism.

15.
J Mol Graph Model ; 125: 108586, 2023 12.
Article in English | MEDLINE | ID: mdl-37567049

ABSTRACT

The reaction mechanism of ethylene (ET) polymerization catalyzed by the phenoxy-imine (FI) ligands using DFT calculations was studied. Among five possible isomers, isomer A which has an octahedral geometry and a (cis-N/trans-O/cis-Cl) arrangement is the most stable pre-reaction Ti-FI dichloride complex. The isomer A can be activated by MAO to form the active catalyst and the active form was used for the study of the mechanism for Ti-FI. The second ethylene insertion was found to be the rate-determining step of the catalyzed ethylene polymerization. To examine the effect of group IVB transition metals (M = Ti, Zr, Hf) substitutions, calculated activation energies at the rate-determining step (EaRDS) were compared, where values of EaRDS of Zr < Hf < Ti agree with experiments. Moreover, we examined the effect of substitution on (O, X) ligands of the Ti-phenoxy-imine (Ti-1) based catalyst. The results revealed that EaRDS of (O, N) > (O, O) > (O, P) > O, S). Hence, the (O, S) ligand has the highest potential to improve the catalytic activity of the Ti-FI catalyst. We also found the activation energy to be related to the Ti-X distance. In addition, a novel Ni-based FI catalyst was investigated. The results indicated that the nickel (II) complex based on the phenoxy-imine (O, N) ligand in the square-planar geometry is more active than in the octahedral geometry. This work provides fundamental insights into the reaction mechanism of M - FI catalysts which can be used for the design and development of M - FI catalysts for ET polymerization.


Subject(s)
Imines , Organometallic Compounds , Polymerization , Ligands , Ethylenes , Metals , Catalysis
16.
J Am Chem Soc ; 145(36): 19953-19960, 2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37584454

ABSTRACT

Dynamic behavior of intermediate adsorbates, such as diffusion, spillover, and reverse spillover, has a strong influence on the catalytic performance in oxide-supported metal catalysts. However, it is challenging to elucidate how the intermediate adsorbates move on the catalyst surface and find active sites to give the corresponding products. In this study, the effect of the dynamic behavior of methoxy intermediate on methanol decomposition on a Pt/TiO2(110) surface has been clarified by combination of scanning tunneling microscopy (STM), temperature-programmed desorption (TPD), and density functional theory (DFT) calculations. The methoxy intermediates were formed by the dissociative adsorption of methanol molecules on Pt nanoparticles at room temperature followed by spillover to the TiO2(110) support surface. TPD results showed that the methoxy intermediates were thermally decomposed at >350 K on the Pt sites to produce CO (dehydrogenation) and CH4 (C-O bond scission). A decrease of the Pt nanoparticle density lowered the activity for the decomposition reaction and increased the selectivity toward CH4, which indicates that the reaction is controlled by diffusion and reverse spillover of the methoxy intermediates. Time-lapse STM imaging and DFT calculations revealed that the methoxy intermediates migrate on the five-fold coordinated Ti (Ti5c) sites along the [001] or [11¯0] direction with the aid of hydrogen adatoms bonded to the bridging oxygens (Obr) and can move over the entire surface to seek and find active Pt sites. This work offers an in-depth understanding of the important role of intermediate adsorbate migration in the control of the catalytic performance in oxide-supported metal catalysts.

17.
J Am Chem Soc ; 145(28): 15054-15060, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37406156

ABSTRACT

Radical cations show a unique reactivity that is fundamentally different from that of conventional cations and have thus attracted considerable attention as alternative cationic intermediates for novel types of organic reactions. However, asymmetric catalysis to promote enantioselective radical cation reactions remains a major challenge in contemporary organic synthesis. Here, we report that the judicious design of an ion pair consisting of a radical cation and a chiral counteranion induces an excellent level of enantioselectivity. This strategy was applied to enantio-, diastereo-, and regioselective [2 + 2] cycloadditions, as well as enantio-, diastereo-, and regioselective [4 + 2] cycloadditions, by using chiral iron(III) photoredox catalysis. We anticipate that this strategy has the potential to expand the use of several mature chiral anions to develop numerous unprecedented enantioselective radical cation reactions.

18.
Dis Model Mech ; 16(7)2023 07 01.
Article in English | MEDLINE | ID: mdl-37415561

ABSTRACT

Phosphoinositides (PIPs) act as intracellular signaling molecules that regulate various cellular processes. Abnormalities in PIP metabolism cause various pathological conditions, including neurodegenerative diseases, cancer and immune disorders. Several neurological diseases with diverse phenotypes, such as ataxia with cerebellar atrophy or intellectual disability without brain malformation, are caused by mutations in INPP4A, which encodes a phosphoinositide phosphatase. We examined two strains of Inpp4a mutant mice with distinct cerebellar phenotypes: the Inpp4aΔEx1,2 mutant exhibited striatal degeneration without cerebellar atrophy, and the Inpp4aΔEx23 mutant exhibited a severe striatal phenotype with cerebellar atrophy. Both strains exhibited reduced expression of Inpp4a mutant proteins in the cerebellum. N-terminal-truncated Inpp4a proteins were expressed from the Inpp4aΔEx1,2 allele by alternative translation initiation and had phosphatase activity for PI(3,4)P2, whereas the Inpp4a mutant protein encoded by Inpp4aΔEx23 completely lacked phosphatase activity. Our results indicate that the diverse phenotypes observed in Inpp4a-related neurological diseases could be due to the varying protein expression levels and retained phosphatase activity in different Inpp4a variants. These findings provide insights into the role of INPP4A mutations in disease pathogenesis and may help to develop personalized therapy.


Subject(s)
Cerebellum , Phosphoric Monoester Hydrolases , Signal Transduction , Animals , Mice , Atrophy/pathology , Cerebellum/pathology , Phenotype , Phosphoric Monoester Hydrolases/genetics , Phosphoric Monoester Hydrolases/metabolism
19.
J Phys Chem A ; 127(19): 4345-4353, 2023 May 18.
Article in English | MEDLINE | ID: mdl-37146038

ABSTRACT

Inverse molecular design allows the optimization of molecules in chemical space and is promising for accelerating the development of functional molecules and materials. To design realistic molecules, it is necessary to consider geometric stability during optimization. In this work, we introduce an inverse design method that optimizes molecular properties by changing the chemical composition in the equilibrium geometry. The optimization algorithm of our recently developed molecular design method has been modified to allow molecular design for general properties at a low computational cost. The proposed method is based on quantum alchemy and does not require empirical data. We demonstrate the applicability and limitations of the present method in the optimization of the electric dipole moment and atomization energy in small chemical spaces for (BF, CO), (N2, CO), BN-doped benzene derivatives, and BN-doped butane derivatives. It was found that the optimality criteria scheme adopted for updating the molecular species yields faster convergence of the optimization and requires a less computational cost. Moreover, we also investigate and discuss the applicability of quantum alchemy to the electric dipole moment.

20.
Autophagy Rep ; 2(1)2023.
Article in English | MEDLINE | ID: mdl-37064812

ABSTRACT

Many neurodegenerative diseases, including Huntington's disease (HD) and Alzheimer's disease (AD), occur due to an accumulation of aggregation-prone proteins, which results in neuronal death. Studies in animal and cell models show that reducing the levels of these proteins mitigates disease phenotypes. We previously reported a small molecule, NCT-504, which reduces cellular levels of mutant huntingtin (mHTT) in patient fibroblasts as well as mouse striatal and cortical neurons from an HdhQ111 mutant mouse. Here, we show that NCT-504 has a broader potential, and in addition reduces levels of Tau, a protein associated with Alzheimer's disease, as well as other tauopathies. We find that in untreated cells, Tau and mHTT are degraded via autophagy. Notably, treatment with NCT-504 diverts these proteins to multivesicular bodies (MVB) and the ESCRT pathway. Specifically, NCT-504 causes a proliferation of endolysosomal organelles including MVB, and an enhanced association of mHTT and Tau with endosomes and MVB. Importantly, depletion of proteins that act late in the ESCRT pathway blocked NCT-504 dependent degradation of Tau. Moreover, NCT-504-mediated degradation of Tau occurred in cells where Atg7 is depleted, which indicates that this pathway is independent of canonical autophagy. Together, these studies reveal that upregulation of traffic through an ESCRT-dependent MVB pathway may provide a therapeutic approach for neurodegenerative diseases.

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