Whole-brain in vivo base editing reverses behavioral changes in Mef2c-mutant mice.

Whole-brain genome editing to correct single-base mutations and reduce or reverse behavioral changes in animal models of autism spectrum disorder (ASD) has not yet been achieved. We developed an apolipoprotein B messenger RNA-editing enzyme, catalytic polypeptide-embedded cytosine base editor (AeCBE) system for converting C·G to T·A base pairs. We demonstrate its effectiveness by targeting AeCBE to an ASD-associated mutation of the MEF2C gene (c.104T>C, p.L35P) in vivo in mice. We first constructed Mef2cL35P heterozygous mice. Male heterozygous mice exhibited hyperactivity, repetitive behavior and social abnormalities. We then programmed AeCBE to edit the mutated C·G base pairs of Mef2c in the mouse brain through the intravenous injection of blood-brain barrier-crossing adeno-associated virus. This treatment successfully restored Mef2c protein levels in several brain regions and reversed the behavioral abnormalities in Mef2c-mutant mice. Our work presents an in vivo base-editing paradigm that could potentially correct single-base genetic mutations in the brain.

The critical role of ASD-related gene CNTNAP3 in regulating synaptic development and social behavior in mice.

Accumulated genetic evidences indicate that the contactin associated protein-like (CNTNAP) family is implicated in autism spectrum disorders (ASD). In this study, we identified genetic mutations in the CNTNAP3 gene from Chinese Han ASD cohorts and Simons Simplex Collections. We found that CNTNAP3 interacted with synaptic adhesion proteins Neuroligin1 and Neuroligin2, as well as scaffolding proteins PSD95 and Gephyrin. Significantly, we found that CNTNAP3 played an opposite role in controlling the development of excitatory and inhibitory synapses in vitro and in vivo, in which ASD mutants exhibited loss-of-function effects. In this study, we showed that the male Cntnap3-null mice exhibited deficits in social interaction， spatial learning and prominent repetitive behaviors. These evidences elucidate the pivotal role of CNTNAP3 in synapse development and social behaviors, providing mechanistic insights into ASD.

[Mitochondrial connexin43 and postconditioning protection in rabbits underwent myocardial ischemia/reperfusion injury].

OBJECTIVE: To investigate the roles of mitochondrial connexin43 (Cx43) and mitochondrial ATP sensitive potassium channe1 (mitoK(ATP)+) in the postconditioning protection for rabbits underwent myocardial ischemia/reperfusion injury. METHODS: In anesthetized open-chest rabbits, the left anterior descending artery (LAD) was occluded for 30 min and reperfused for 4 h and randomly divided into four groups (n = 16 each): sham operation group (Sham), ischemic reperfusion group (IR), ischemic postconditioning group (PC) and PC plus 5-HD, a specific mitoK(ATP)+ inhibitor (PC + 5-HD). Rabbits were sacrificed post 4 h reperfusion. Heart rate and the mean arterial pressure were recorded and plasma CK-MB and cTnI activity were measured at baseline, at the end of ischemia, and after 2 h and 4 h of reperfusion, respectively. Myocardial infarct size was determined and mitochondria structure was observed under electron microscope at the end of the experiment. Mitochondria were isolated and the protein content of the mitochondrial Cx43 was determined by Western blot. RESULTS: Plasma CK-MB, cTnI activity and myocardial infarct size were significantly reduced in PC [(19.1 +/- 3.9)%] group compared to IR [(35.7 +/- 5.8)%] and PC + 5HD [(34.2 +/- 3.9)%] groups (all P < 0.01). Degree of mitochondria damage was significantly reduced in PC group compared to IR and PC + 5HD groups (all P < 0.01). The mitochondria Cx43 content was significantly decreased in IR group and PC + 5-HD group compared to sham group (all P < 0.05) and restored in PC group. CONCLUSION: Ischemic postconditioning protected the heart from I/R injury by improving mitochondrial ultrastructure and by attenuating I/R induced decrease of mitochondria Cx43 expression. The protective effects of postconditioning was partly mediated by activating mitoK(ATP)+ pathway.

[Transarterial oily chemoembolization combined with interstitial laser thermotherapy for treatment of hepatocellular carcinoma].

OBJECTIVE: To evaluate the therapeutic effects and adverse effects of transarterial oily chemoembolization combined with interstitial laser thermotherapy (TOCE+ILT) in the treatment of hepatocellular carcinoma. METHODS: Totally 120 patients with hepatocellular carcinoma were randomized into two groups and received interventions with TOCE+ILT or TOCE combined with percutaneous ethanol injection (TOCE+PEI). The treatment was repeated when necessary until the tumor was completely ablated, after which the therapeutic effects were evaluated and the patients were the followed up for observing long-term clinical outcome. RESULTS: Of the 120 patients enrolled in this observation, 105 were followed up for two years (54 in TOCE+ILT group and 51 in TOCE+PEI group). The complete tumor necrosis rate of TOCE+ILT group was significantly higher than that of the TOCE+PEI group (84.8% vs 73.9%,Chi(2)=4.405, P=0.036), and TOCE+ILT was associated with a significantly higher negative conversion rate of AFP positivity (77.8% vs 56.1%, Chi(2)=4.592, P=0.032). The 1-year survival rate were similar between two groups, but the 2-year survival rate was significantly higher in patients with TOCE+ILT (79.6% vs 60.8%, Chi(2)=4.477, P=0.034). The hepatic function was comparable between the two groups before treatment, and 1 week after treatment, the ALT level in patients undergoing TOCE+ILT was significantly lower than that in patients with TOCE+PEI (95.90-/+56.06 U/L vs 116.31-/+45.27 U/L, t=2.04, P=0.043). Post-embolization syndrome was observed in the patients in two groups, but no severe adverse events were found. CONCLUSION: TOCE+ILT has good therapeutic effects and mild side effects in the treatment of hepatocellular carcinoma.

[Long-term result of combination of transcatheter arterial chemoembolization and percutaneous ethanol injection for treatment of hepatocellular carcinoma].

BACKGROUND & OBJECTIVE: Both transcatheter arterial chemoembolization (TACE) and percutaneous ethanol injection (PEI) are the most important and popular procedures of interventional treatment for hepatocellular carcinoma (HCC). Although the improvement of the short-term efficacy of the combination of TACE and PEI has been proved, the long-term efficacy is seldom reported so far. The purpose of this study was to evaluate the long-term efficacy of the combination of TACE and PEI for treatment of HCC. METHODS: Six hundred and seventy-five patients with HCC from 2 cm to 15 cm in the greatest diameter (average 9.6 cm) were enrolled in this study. Among them, 179 were treated by a combination of TACE using the emulsion of lipiodol and anti-cancer drugs and PEI (TACE/PEI group) and 496 patients by TACE alone (TACE group). Ten patients in each group underwent resection after the final interventional treatment and the resected specimens were detected by histopathology method. The unresected patients had been followed up for 5-7 years and the 1-, 3-, 5 -, and 7-year survival rates were evaluated. The clinical data of the patients in two groups before intervention were comparable. RESULTS: Pathological data of two groups showed that remarkable differences were found in the mean necrosis rates (100.0+/-0.0% vs 91.5+/-7.1%, P< 0.05) and the complete necrosis rates of tumors (100% vs 20%, P = 0.0007), while there were no statistical significances in the extent of shrinkage of tumors after treatment between two groups. The results of follow-up showed that the 1-, 3-, 5-, and 7-year survival rates were 80.5%, 58.6%, 29.6%, 16.5% in TACE-PEI group, and 68.5%, 27.8%, 7.2%, 5.2% in TACE group, respectively. Significant differences were found between two groups (P< 0.01). CONCLUSION: The combination of TACE and PEI is a valuable remedy for HCC to prolong long-term survival rate.