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Small molecule modulator of aggrephagy regulates neuroinflammation to curb pathogenesis of neurodegeneration.

ABSTRACT: BACKGROUND:Plethora of efforts fails to yield a single drug to reverse the pathogenesis of Parkinson's disease (PD) and related ?-synucleopathies. METHODS:Using chemical biology, we identified a small molecule inhibitor of c-abl kinase, PD180970 that could potentially clear the toxic protein aggregates. Genetic, molecular, cell biological and immunological assays were performed to understand the mechanism of action. In vivo preclinical disease model of PD was used to assess its neuroprotection efficacy. FINDINGS:In this report, we show the ability of a small molecule inhibitor of tyrosine kinases, PD180970, to induce autophagy (cell lines and mice midbrain) in an mTOR-independent manner and ameliorate the ?-synuclein mediated toxicity. PD180970 also exerts anti-neuroinflammatory potential by inhibiting the release of proinflammatory cytokines such as IL-6 (interleukin-6) and MCP-1 (monocyte chemoattractant protein-1) through reduction of TLR-4 (toll like receptor-4) mediated NF-?B (nuclear factor kappa-light-chain-enhancer of activated B cells) activation. In vivo studies show that PD180970 is neuroprotective by degrading the toxic protein oligomers through induction of autophagy and subsiding the microglial activation. INTERPRETATION:These protective mechanisms ensure the negation of Parkinson's disease related motor impairments. FUND: This work was supported by Wellcome Trust/DBT India Alliance Intermediate Fellowship (500159-Z-09-Z), DST-SERB grant (EMR/2015/001946), DBT (BT/INF/22/SP27679/2018) and JNCASR intramural funds to RM, and SERB, DST (SR/SO/HS/0121/2012) to PAA, and DST-SERB (SB/YS/LS-215/2013) to JPC and BIRAC funding to ETA C-CAMP.

SUBMITTER: Sn S

PROVIDER: S-EPMC6921191 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Small molecule modulator of aggrephagy regulates neuroinflammation to curb pathogenesis of neurodegeneration.

Sn Suresh S Pandurangi Janhavi J Murumalla Ravi R Dj Vidyadhara V Garimella Lakshmi L Acharya Achyuth A Rai Shashank S Paul Abhik A Yarreiphang Haorei H Pillai Malini S MS Giridharan Mridhula M Clement James P JP Alladi Phalguni Anand PA Saiyed Taslimarif T Manjithaya Ravi R

EBioMedicine 20191111

<h4>Background</h4>Plethora of efforts fails to yield a single drug to reverse the pathogenesis of Parkinson's disease (PD) and related α-synucleopathies.<h4>Methods</h4>Using chemical biology, we identified a small molecule inhibitor of c-abl kinase, PD180970 that could potentially clear the toxic protein aggregates. Genetic, molecular, cell biological and immunological assays were performed to understand the mechanism of action. In vivo preclinical disease model of PD was used to assess its ne ...[more]

PMID: 31727601

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Project description:Metastasis, the spread and growth of tumor cells to distant organ sites, represents the most devastating attribute and plays a major role in the morbidity and mortality of cancer. Inflammation is crucial for malignant tumor transformation and survival. Thus, blocking inflammation is expected to serve as an effective cancer treatment. Among anti-inflammation therapies, chemokine modulation is now beginning to emerge from the pipeline. CXC chemokine receptor-4 (CXCR4) and its ligand stromal cell-derived factor-1 (CXCL12) interaction and the resulting cell signaling cascade have emerged as highly relevant targets since they play pleiotropic roles in metastatic progression. The unique function of CXCR4 is to promote the homing of tumor cells to their microenvironment at the distant organ sites.We describe the actions of N,N'-(1,4-phenylenebis(methylene))dipyrimidin-2-amine (designated MSX-122), a novel small molecule and partial CXCR4 antagonist with properties quite unlike that of any other reported CXCR4 antagonists, which was prepared in a single chemical step using a reductive amination reaction. Its specificity toward CXCR4 was tested in a binding affinity assay and a ligand competition assay using (18)F-labeled MSX-122. The potency of the compound was determined in two functional assays, Matrigel invasion assay and cAMP modulation. The therapeutic potential of MSX-122 was evaluated in three different murine models for inflammation including an experimental colitis, carrageenan induced paw edema, and bleomycin induced lung fibrosis and three different animal models for metastasis including breast cancer micrometastasis in lung, head and neck cancer metastasis in lung, and uveal melanoma micrometastasis in liver in which CXCR4 was reported to play crucial roles.We developed a novel small molecule, MSX-122, that is a partial CXCR4 antagonist without mobilizing stem cells, which can be safer for long-term blockade of metastasis than other reported CXCR4 antagonists.

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Small molecule modulator of aggrephagy regulates neuroinflammation to curb pathogenesis of neurodegeneration.

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Small molecule modulator of aggrephagy regulates neuroinflammation to curb pathogenesis of neurodegeneration.

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