J Biochem. 2020 Sep 1;168(3):305-312. doi: doi: 10.1093/jb/mvaa050. PMID: 32302394.
This study shows that mice mitochondrial regulatory gene Mitol-deficient mice display reduced growth in combination with anterior pituitary hypoplasia and reduced growth hormone levels.
MITOL encodes a ubiquitin ligase. Ablation of Mitol in nestin-expressing cells led to reduced expression of Gh, Prl, Ghrhr, and Pit1, suggesting dysregulation of pituitary transcription factor Pit1 by a yet unidentified mechanism. MITOL expression was significantly reduced in the posterior pituitary of the Mitol-deficient mice. Interestingly, the anterior pituitary MITOL expression was not remarkably changed, and, given that the nestin-positive anterior pituitary cell population in mice is very small, the authors hypothesized that it represented somatotroph progenitors that fail to differentiate into GH-secreting cells.
Many patients with mitochondrial diseases present with growth failure. These findings suggest that mitochondrial dysfunction may possibly underlie cases with unexplained hypopituitarism.