Small molecule C381 targets the lysosome to reduce inflammation and ameliorate disease in models of neurodegeneration

Abstract

Significance Neurodegenerative diseases are poorly understood and difficult to treat. One common hallmark is lysosomal dysfunction leading to the accumulation of aggregates and other undegradable materials, which cause damage to brain resident cells. Lysosomes are acidic organelles responsible for breaking down biomolecules and recycling their constitutive parts. In this work, we find that the antiinflammatory and neuroprotective compound, discovered via a phenotypic screen, imparts its beneficial effects by targeting the lysosome and restoring its function. This is established using a genome-wide CRISPRi target identification screen and then confirmed using a variety of lysosome-targeted studies. The resulting small molecule from this study represents a potential treatment for neurodegenerative diseases as well as a research tool for the study of lysosomes in disease.

Proteostasis and lysosomal quality control deficits in Alzheimer’s disease neurons

“…Based on these findings, targeting lysosomal acidification has become a desired strategy. Re-acidifying lysosomes by v-ATPase-targeting compounds (for example, EN6 and C381) or endocytosed nanoparticles (for example, PLGA-aNP and NP-1) showed promising effects on promoting the clearance of protein aggregates, rescue of autophagic dysfunction and attenuation of neuroinflammation and neurodegeneration in different pathological contexts(Bourdenx et al, 2016; Chung et al, 2019; Lee et al, 2015; Vest et al, 2022). The v-ATPase-targeting compound, C381 can rescue deficits in lysosomal acidification and disease-relevant pathologies in both neurons and glial cells in disease models for AD, PD and FTD.…”

“…The v-ATPase-targeting compound, C381 can rescue deficits in lysosomal acidification and disease-relevant pathologies in both neurons and glial cells in disease models for AD, PD and FTD. Further, C381 is orally bioavailable and brain penetrant, reflecting good translational potential (Vest et al, 2022). Administration of mTOR inhibitor, rapamycin, was shown to reduce neuropathology in mouse models for AD (Talboom et al, 2015), although its associated immunosuppression effects reduces translation potential for AD.…”

“…We previously identified a brain-penetrant lysosomal v-ATPase complex activator, C381, that promotes lysosomal acidification. C381 can reduce neuroinflammation, protein aggregates and neurodegeneration in mouse models of PD and FTD (Vest et al, 2022). Another compound, thioperamide, increases a late endosomal and lysosomal phospholipid, bis(monoacylglycero)phosphate (BMP), and rescues defects in lysosomal lipid metabolism and membrane permeabilization in lysosomal storage disorders (Moreau et al, 2019).…”

“…Transcardial perfusion with 50 ml cold PBS was performed using a peristaltic pump with the perfusate flow rate not exceeding 10 ml/min. Brain tissue processing was performed as described previously (Vest et al, 2022;Villeda et al, 2014). Hemibrains were isolated and fixed in 4% PFA overnight at 4°C before transferring to 30% sucrose in PBS at 4 °C for preservation.…”

Lysosome-acidifying nanoparticles rescue A30P α-synuclein induced neuronal death in cellular andDrosophilamodels of Parkinson’s disease

“…Apart from lysosome-acidifying nanoparticles (27, 34, 36, 45, 46), there are several other strategies such as small molecules that target lysosomal proton pump and ion channels that have been developed to restore lysosomal acidification. For example, C381 activates lysosomal vacuolar H + -ATPase and promotes lysosomal acidification in neurotoxin MPTP treated mouse model of PD (47). ML-SA1 is an agonist of lysosomal channel transient receptor potential mucolipin 1 that has been shown to enhance lysosomal acidification and promote clearance of A53T αSyn in HEK293 cells and WT αSyn in immortalized human dopaminergic neurons (48).…”