Cell Death and Neurodegeneration.
Ontology highlight
ABSTRACT:
SUBMITTER: Andreone BJ
PROVIDER: S-EPMC6996453 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Mutations in the macroautophagy/autophagy gene WDR45 cause β-propeller protein-associated neurodegeneration (BPAN); however the molecular and cellular mechanism of the disease process is largely unknown. Here we generated constitutive wdr45 knockout (KO) mice that displayed cognitive impairments, abnormal synaptic transmission and lesions in several brain regions. Immunohistochemistry analysis showed loss of neurons in prefrontal cortex and basal ganglion in aged mice, and increased apoptosis in prefrontal cortex, recapitulating a hallmark of neurodegeneration. Quantitative proteomic analysis showed accumulation of endoplasmic reticulum (ER) proteins in KO mouse. At the cellular level, accumulation of ER proteins due to WDR45 deficiency resulted in increased ER stress and impaired ER quality control. The unfolded protein response (UPR) was elevated through ERN1/IRE1 or EIF2AK3/PERK pathway, and eventually led to neuronal apoptosis. Suppression of ER stress or activation of autophagy through MTOR inhibition alleviated cell death. Thus, the loss of WDR45 cripples macroautophagy machinery in neurons and leads to impairment in organelle autophagy, which provides a mechanistic understanding of cause of BPAN and a potential therapeutic strategy to treat this genetic disorder.Abbreviations: 7-ADD: 7-aminoactinomycin D; ASD: autistic spectrum disorder; ATF6: activating transcription factor 6; ATG: autophagy-related; BafA1: bafilomycin A1; BCAP31: B cell receptor associated protein 31; BPAN: β-propeller protein-associated neurodegeneration; CCCP: carbonyl cyanide m-chlorophenylhydrazone; CDIPT: CDP-diacylglycerol-inositol 3-phosphatidyltransferase (phosphatidylinositol synthase); DDIT3/CHOP: DNA-damage inducible transcript 3; EIF2A: eukaryotic translation initiation factor 2A; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; ER: endoplasmic reticulum; ERN1/IRE1: endoplasmic reticulum to nucleus signaling 1; GFP: green fluorescent protein; HIP: hippocampus; HSPA5/GRP78: heat shock protein family A (HSP70) member 5; KO: knockout; LAMP1: lysosomal-associated membrane 1; mEPSCs: miniature excitatory postsynaptic currents; MG132: N-benzyloxycarbonyl-L-leucyl-L-leucyl-L-leucinal; MIB: mid-brain; MTOR: mechanistic target of rapamycin kinase; PCR: polymerase chain reaction; PFA: paraformaldehyde; PFC: prefrontal cortex; PRM: parallel reaction monitoring; RBFOX3/NEUN: RNA binding protein, fox-1 homolog [C. elegans] 3; RTN3: reticulon 3; SEC22B: SEC22 homolog B, vesicle trafficking protein; SEC61B: SEC61 translocon beta subunit; SEM: standard error of the mean; SNR: substantia nigra; SQSTM1/p62: sequestosome 1; TH: tyrosine hydroxylase; Tm: tunicamycin; TMT: tandem mass tag; TUDCA: tauroursodeoxycholic acid; TUNEL: terminal deoxynucleotidyl transferase dUTP nick-end labeling; UPR: unfolded protein response; WDR45: WD repeat domain 45; WT: wild type; XBP1: X-box binding protein 1.
| S-EPMC6999610 | biostudies-literature
Project description:Interventions: Participants will be intravenously administered 1.8-2.2MBq/kg (maximum 220MBq) of [68Ga]gallium 2,2’-(7-(4-((1-carboxy-4-((1-((carboxymethyl)amino)-3-((2-((4-(dihydroxyarsaneyl)phenyl)amino)-2-oxoethyl)thio)-1-oxopropan-2-yl)amino)-4-oxobutyl)amino)-1-carboxylato-4-oxobutyl)-1,4,7-triazonane-1,4-diyl)diacetate (68Ga Cell Death Indicator [68Ga-CDI]) on two occasions, once within 14 days prior to commencing treatment and the second between day 15 and day 20 (inclusive) after commencement of treatment (chemoradiotherapy in the case of oesophageal / gastro-oesophageal and rectal carcinoma and chemotherapy in the case of breast carcinoma and lymphoma).
One hour following each 68Ga-CDI administration, participants will undergo a positron emission tomography (PET) scan where they will lie still on a scanning bed (breathing normally). The scan will take approximately 30 minutes.
68Ga-CDI will be administered by a nuclear medicine specialist or medical radiation scientist. 68Ga-CDI administration and PET scannning will occur at the Prince of Wales Hospital, Randwick, NSW.
Primary outcome(s): Tumour uptake of 68Ga-CDI assessed on PET scan.[Tumour uptake of 68Ga-CDI assessed on PET scan performed within 14 days prior to commencement of treatment and then again between 15 and 20 days after commencing treatment.]
Study Design: Purpose: Diagnosis; Allocation: Non-randomised trial; Masking: Open (masking not used);Assignment: Single group;Type of endpoint: Safety/efficacy
| 2472264 | ecrin-mdr-crc