title: Ultrastructural variations in platelets and platelet mitochondria: a novel feature in amyotrophic lateral sclerosis.
abstract: Platelets are characterized as a systemic tool to elucidate mitochondria-allied perturbance in neurological diseases. The authors studied ultrastructural changes in platelets and platelet mitochondria using a case-control approach in amyotrophic lateral sclerosis (ALS). Subjects were sporadic ALS cases (n = 22) and age- and sex-matched controls (n = 16). Phlebotomy was performed, platelet concentrates (PCs) were prepared, and mitochondria were extracted. PCs and mitochondria were processed for ultrastructure study using transmission electron microscopy. Image analysis was done using Image-J. Transmission electron microscopy demonstrated both qualitative and quantitative variations in ALS platelets and platelet mitochondria. Heterogeneous distribution of granules, formation of vacuoles, blebs, pseudopodia, loose demarcation of cell membrane with a significant increase in area (20.3%), perimeter (17.82%), integrated density (21.44%), electron-lucent granules (41.79%), and vacuoles (36.58%) were observed in ALS platelets. Conversely, control platelets exhibited an increase of circularity (11.7%) and electron-dense granules (36.89%). In parallel, nonuniformity of matrix, faint cristae, greater lysosomal bodies, and lesser intramitochondrial granules were seen in ALS platelet mitochondria. Significantly greater area (26.88%), perimeter (15%), circularity (3.76%), and integrated density (25.18%) were observed in control platelet mitochondria. Ultastructural divergence in platelets of ALS patients underlines a potential dependence of platelets on modest mitochondrial functioning. These observations also support the view that systemic involvement might be a novel feature in ALS pathophysiology.
authors.affiliation: Department of Neurobiochemistry, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Mohita
authors.initials: M
authors.lastname: Shrivastava
authors.forename: Taposh K
authors.initials: TK
authors.lastname: Das
authors.forename: Madhuri
authors.initials: M
authors.lastname: Behari
authors.forename: Uttam
authors.initials: U
authors.lastname: Pati
authors.forename: S
authors.initials: S
authors.lastname: Vivekanandhan
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000097:blood / Q000473:pathology*; D001792:Blood Platelets / Q000648:ultrastructure*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007194:India; D008297:Male; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D008928:Mitochondria / Q000648:ultrastructure*; D018962:Phlebotomy