Ataxia with giant axonopathy in Acbd5-deficient mice halted by adeno-associated virus gene therapy

Acyl-CoA binding domain containing 5 (ACBD5) is a critical player in handling very long chain fatty acids (VLCFA) en route for peroxisomal β-oxidation. Mutations in ACBD5 lead to the accumulation of VLCFA and patients present retinal dystrophy, ataxia, psychomotor delay and a severe leukodystrophy. Using CRISPR/Cas9, we generated and characterized an Acbd5 Gly357* mutant allele. Gly357* mutant mice recapitulated key features of the human disorder, including reduced survival, impaired locomotion and reflexes, loss of photoreceptors, and demyelination. The ataxic presentation of Gly357* mice involved the loss of cerebellar Purkinje cells and a giant axonopathy throughout the CNS. Lipidomic studies provided evidence for the extensive lipid dysregulation caused by VLCFA accumulation. Following a proteomic survey, functional studies in neurons treated with VLCFA unravelled a deregulated cytoskeleton with reduced actin dynamics and increased neuronal filopodia. We also show that an adeno-associated virus-mediated gene delivery ameliorated the gait phenotypes and the giant axonopathy, also improving myelination and astrocyte reactivity. Collectively, we established a mouse model with significance for VLCFA-related disorders. The development of relevant neuropathological outcomes enabled the understanding of mechanisms modulated by VLCFA and the evaluation of the efficacy of preclinical therapeutic interventions.

Mob4 is essential for spermatogenesis in Drosophila melanogaster

Gamete formation is essential for sexual reproduction in metazoans. Meiosis in males gives rise to spermatids that must differentiate and individualize into mature sperm. In Drosophila melanogaster, individualization of interconnected spermatids requires the formation of individualization complexes that synchronously move along the sperm bundles. Here, we show that Mob4, a member of the Mps-one binder family, is essential for male fertility but has no detectable role in female fertility. We show that Mob4 is required for proper axonemal structure and its loss leads to male sterility associated with defective spermatid individualization and absence of mature sperm in the seminal vesicles. Transmission electron micrographs of developing spermatids following mob4RNAi revealed expansion of the outer axonemal microtubules such that the 9 doublets no longer remained linked to each other and defective mitochondrial organization. Mob4 is a STRIPAK component, and male fertility is similarly impaired upon depletion of the STRIPAK components, Strip and Cka. Expression of the human Mob4 gene rescues all phenotypes of Drosophila mob4 downregulation, indicating that the gene is evolutionarily and functionally conserved. Together, this suggests that Mob4 contributes to the regulation of the microtubule- and actin-cytoskeleton during spermatogenesis through the conserved STRIPAK complex. Our study advances the understanding of male infertility by uncovering the requirement for Mob4 in sperm individualization.

Oral hygiene of children with cleft lip and palate: Efficacy of the cleft toothbrush - A designed add-on to regular toothbrushes

BACKGROUND

The anatomical and morphological alterations associated with cleft lip and palate (CLP) favour the buildup of dental plaque.

AIM

To assess the efficacy of a new add-on to regular toothbrush-the Cleft Toothbrush, in removing the dental plaque of CLP patients, compared to a regular toothbrush.

DESIGN

Forty-five children with CLP were randomly organized into two groups: A (n = 26, 2-6 years old) and B (n = 19, 7-12 years old). They were evaluated at days 0, 15, 30, and 60. After brushing their teeth with a regular toothbrush or with the Cleft Toothbrush, the dental plaque was recorded using an adapted Plaque Index (aPI). Data analyses were performed in IBM SPSS(c) , and all statistic inference comparisons were made using non-parametric tests.

RESULTS

In the first 15 days, children used a new regular toothbrush and aPI-C (teeth adjacent to the cleft) was recorded. The Cleft Toothbrush, used by all children from day 15 to day 30, showed high efficacy in removing dental plaque in the cleft area, evidenced by significantly lower aPI-C values, compared to those observed with the regular toothbrush (P < 0.001). When given free option of brushing technique, from day 30 to day 60, most of the children (38 out of 45) chose the Cleft Toothbrush.

CONCLUSIONS

The Cleft Toothbrush showed high efficacy in removing dental plaque in the cleft area, and presented high level of acceptance by parents and children, compared to a regular toothbrush. This is expected to improve the health status of the local adjacent tissues, a requirement for their rehabilitation.