Fig. 3.

Imipridone-induced ClpP hyperactivation leads to mitochondrial damage and impaired mitochondrial metabolism in DMGs. (A) Protein expression of ClpP and ClpX (top panel), NDUFA12 (middle panel), and respiratory chain complexes I, II, IV components (bottom panel) decreased in ONC201 and ONC206 treated cells (B) ONC201 and ONC206 treatment (24 hrs IC₅₀) decreased mitochondrial membrane potential, with a larger reduction in ONC206 treated cells. scale bar 50 µm. (C) ONC206 resulted in greater (top panel, 24 hrs treatment) and earlier (bottom panel, 4 vs 24 hrs treatment at IC₅₀) production of mitochondrial ROS. (D) Superoxide production in mitochondria was increased after 24 hrs treatment. Scale bar 50 µm. (E) TEM revealed mitochondrial morphological abnormalities in DMG cells treated with ONC201 (24 hrs, IC₅₀) where a temporal sequence of events was observed including cristae disintegration and cristae whirl formation (1), mitochondrial swelling (2-3), and possible encapsulation/vacuolation of mitochondria (4). Control DMSO-treated cells showed healthy mitochondria with round, dense morphologies, and an absence of cristae whirl formation. Scale bar 1 µm.