Vanishing White Matter Disease Diagnosis After Athletic Concussion in an Adolescent Male Patient

Edaravone and mitochondrial transfer as potential therapeutics for vanishing white matter disease astrocyte dysfunction

INTRODUCTION

Previous research has suggested that vanishing white matter disease (VWMD) astrocytes fail to fully differentiate and respond differently to cellular stresses compared to healthy astrocytes. However, few studies have investigated potential VWMD therapeutics in monoculture patient-derived cell-based models.

METHODS

To investigate the impact of alterations in astrocyte expression and function in VWMD, astrocytes were differentiated from patient and control induced pluripotent stem cells and analyzed by proteomics, pathway analysis, and functional assays, in the absence and presence of stressors or potential therapeutics.

RESULTS

Vanishing white matter disease astrocytes demonstrated significantly reduced expression of astrocyte markers and markers of inflammatory activation or cellular stress relative to control astrocytes. These alterations were identified both in the presence and absence of polyinosinic:polycytidylic acid stimuli, which is used to simulate viral infections. Pathway analysis highlighted differential signaling in multiple pathways in VWMD astrocytes, including eukaryotic initiation factor 2 (EIF2) signaling, oxidative stress, oxidative phosphorylation (OXPHOS), mitochondrial function, the unfolded protein response (UPR), phagosome regulation, autophagy, ER stress, tricarboxylic acid cycle (TCA) cycle, glycolysis, tRNA signaling, and senescence pathways. Since oxidative stress and mitochondrial function were two of the key pathways affected, we investigated whether two independent therapeutic strategies could ameliorate astrocyte dysfunction: edaravone treatment and mitochondrial transfer. Edaravone treatment reduced differential VWMD protein expression of the UPR, phagosome regulation, ubiquitination, autophagy, ER stress, senescence, and TCA cycle pathways. Meanwhile, mitochondrial transfer decreased VWMD differential expression of the UPR, glycolysis, calcium transport, phagosome formation, and ER stress pathways, while further modulating EIF2 signaling, tRNA signaling, TCA cycle, and OXPHOS pathways. Mitochondrial transfer also increased the gene and protein expression of the astrocyte marker, glial fibrillary acidic protein (GFAP) in VWMD astrocytes.

CONCLUSION

This study provides further insight into the etiology of VWMD astrocytic failure and suggests edaravone and mitochondrial transfer as potential candidate VWMD therapeutics that can ameliorate disease pathways in astrocytes related to oxidative stress, mitochondrial dysfunction, and proteostasis.

Adult polyglucosan body disease: an acute presentation leading to unmasking of this rare disorder

Introduction: Adult polyglucosan body disease (APBD) is an autosomal recessive leukodystrophy caused by abnormal intracellular accumulation of glycogen byproducts. This disorder is linked to a deficiency in glycogen branching enzyme-1 (GBE-1). Neurologic manifestations include upper and lower motor neuron signs, dementia, and peripheral neuropathy. APBD is typically a progressive disease. In this report, we discuss a novel case of APBD in a patient who had a sudden onset of spastic quadriparesis preceded by gradual difficulty with gait. Genetic and postmortem analysis confirmed the diagnosis of APBD.Case report: A 65-year-old man was evaluated for a new-onset of spastic quadriparesis, right-gaze preference, and left-sided beat nystagmus. Magnetic resonance imaging (MRI) of the brain revealed areas of white matter hyperintensities most prominent in the brainstem and periventricular regions. MRI of the cervical spine showed marked cord atrophy. Laboratory workup and cerebrospinal fluid analysis were unremarkable. Genetic testing supported the diagnosis of APBD due to GBE-1 deficiency. Postmortem analysis showed multiple white matter abnormalities suggestive of a leukodystrophy syndrome, and histopathologic testing revealed abnormal accumulation of polyglucosan bodies in samples from the patient's central nervous system supporting the diagnosis of APBD.Conclusion: APBD is a rare disorder that can affect the nervous system. The diagnosis can be confirmed with a combination of genetic testing and pathologic analysis of affected brain tissue.