Activity-dependent neuroprotective protein deficiency models synaptic and developmental phenotypes of autism-like syndrome
Gal Hacohen-Kleiman, … , R. Anne McKinney, Illana Gozes
Gal Hacohen-Kleiman, … , R. Anne McKinney, Illana Gozes
Published August 14, 2018
Citation Information: J Clin Invest. 2018;128(11):4956-4969. https://doi.org/10.1172/JCI98199.
View: Text | PDF
Research Article

Activity-dependent neuroprotective protein deficiency models synaptic and developmental phenotypes of autism-like syndrome

Abstract

Previous findings showed that in mice, complete knockout of activity-dependent neuroprotective protein (ADNP) abolishes brain formation, while haploinsufficiency (Adnp+/–) causes cognitive impairments. We hypothesized that mutations in ADNP lead to a developmental/autistic syndrome in children. Indeed, recent phenotypic characterization of children harboring ADNP mutations (ADNP syndrome children) revealed global developmental delays and intellectual disabilities, including speech and motor dysfunctions. Mechanistically, ADNP includes a SIP motif embedded in the ADNP-derived snippet drug candidate NAP (NAPVSIPQ, also known as CP201), which binds to microtubule end–binding protein 3, essential for dendritic spine formation. Here, we established a unique neuronal membrane–tagged, GFP-expressing Adnp+/– mouse line allowing in vivo synaptic pathology quantification. We discovered that Adnp deficiency reduced dendritic spine density and altered synaptic gene expression, both of which were partly ameliorated by NAP treatment. Adnp+/–mice further exhibited global developmental delays, vocalization impediments, gait and motor dysfunctions, and social and object memory impairments, all of which were partially reversed by daily NAP administration (systemic/nasal). In conclusion, we have connected ADNP-related synaptic pathology to developmental and behavioral outcomes, establishing NAP in vivo target engagement and identifying potential biomarkers. Together, these studies pave a path toward the clinical development of NAP (CP201) for the treatment of ADNP syndrome.

Authors

Gal Hacohen-Kleiman, Shlomo Sragovich, Gidon Karmon, Andy Y. L. Gao, Iris Grigg, Metsada Pasmanik-Chor, Albert Le, Vlasta Korenková, R. Anne McKinney, Illana Gozes

×

Figure 7

Influence of the Adnp genotype on motor, memory, and social aspects, all of which improve with NAP treatment.

Options: View larger image (or click on image) Download as PowerPoint
Influence of the Adnp genotype on motor, memory, and social aspects, all...
A 2-way ANOVA or 2-way, repeated-measures ANOVA with Tukey’s post hoc test was performed (males: Adnp+/+ n = 20, Adnp+/– n = 12, Adnp+/– NAP, n = 9; females: Adnp+/+ n = 14–15, Adnp+/– n = 7, Adnp+/– NAP, n = 20). (A) To assess neuromuscular ability, the latency (seconds) to fall off an inverted cage lid was determined by a hanging wire test. For males, a main group effect was found [F(3,49) = 8.186, P < 0.001], with significant differences between Adnp+/+ and Adnp+/– mice and NAP- versus vehicle-treated Adnp+/– mice (**P < 0.01, 2-way ANOVA). Sex differences were found among Adnp+/– mice (**P < 0.01, Mann-Whitney U test). (B) To assess forelimb grip strength, peak grip force was evaluated. For males, a main group effect was found [F(3,49) = 6.154, P = 0.001], with significant differences between Adnp+/+ and Adnp+/– mice and NAP- versus vehicle-treated Adnp+/– mice (**P < 0.01, 2-way ANOVA). Sex differences were found in Adnp+/– mice (*P < 0.05, Mann-Whitney U test). FG, grip force. (C) For object recognition assessment, a main genotype effect in males [F(1,49) = 7.037, P = 0.011] and a main interaction effect in females [F(1,56) = 5.386, P = 0.024] were found. In both sexes, significant differences between Adnp+/+ and Adnp+/– mice and NAP- versus vehicle-treated Adnp+/– mice were observed (*P < 0.05 and ***P < 0.001). The discrimination 2 score (D2) was determined using the following equation: D2 = (b – a)/(b + a), where a = time spent exploring the familiar object, and b = time spent exploring the novel object. (D) For social recognition among female mice, a main effect for the sniffed item was found [F(1,56) = 30.447, P < 0.001], with significant differences between the time spent sniffing the cup and the mouse for Adnp+/+ mice (**P < 0.01) and NAP-treated Adnp+/– mice (***P < 0.001 vs. cup). (E) Female Adnp+/– mice exhibited impaired olfactory function, which was restored by NAP treatment. *P < 0.05, **P < 0.01, and ***P < 0.001 versus previous sniffing (novel vs. familiar odor), by paired Student’s t test (Adnp+/+ n = 11, Adnp+/– n = 5, Adnp+/– NAP n = 15). (F) Social memory was assessed. For males, main treatment [F(1,49) = 4.573, P = 0.037] and interaction [F(1,49) = 4.473, P = 0.040] effects were found. For females, a significant main interaction effect [F(1,56) = 4.463, P = 0.039] was found. Among both sexes, significant differences between Adnp+/+ and Adnp+/– mice and NAP- versus vehicle-treated Adnp+/– mice were observed (*P < 0.05 and **P < 0.01). (A–C and F) Adnp+/+ data are reshown in Supplemental Figure 14, A–D. (D and E) Adnp+/+ data are reshown in Supplemental Figure 14, E and G.