Effect of curcumin on autophagy apoptosis and histocytic renovation in mice after traumatic brain injury

Abstract

Objective To explore the therapeutic effect of curcumin on neronal apoptosis, autophagy and neural renovation in cerebral cortex of mice after traumatic brain injury (TBI). Methods A total of 90 mice were randomly divided into 4 groups: blank control group (N=12), sham group (N=26), TBI+NaCl group (N=26, NaCl was pretreated by intraperitoneal injection 30min after TBI) and TBI+ curcumin group (N=26,curcumin was pretreated by intraperitoneal injection 30 min after TBI). Propidium iodide (PI)-labeled cell-counting was used to study the cell protective effect of curcumin. Expression of apoptosis and autophagy related proteins B celllymphoma (Bcl-2),activated Caspase-3, P62, microtubule-associated protein 1 light chain 3 (MAP1LC3-Ⅱ) were detected by Western Blotting. The lesion volume of cortex was tested by Cavalieri mothod. Results PI positive cells significantly increased 48h after TBI (t= 26.000, P=0.000; t=18.520, P=0.000), and reduced after curcumin injection (t=3.686, P=0.014); in cortex lesion area,expression level of apoptosis associated protein Bcl-2 decreased(t=5.656, P=0.000; t= 3.254, P =0.008; t =4.485, P =0.001; t =3.150, P =0.009), expression level of activated Caspase-3 increased (t=8.534, P=0.000; t=3.468, P=0.005; t=8.565, P=0.000; t=2.846, P=0.016), expression level of autophagy associated protein P62 decreased (t=3.574, P=0.004; t=7.612, P=0.000; t=3.465, P= 0.005; t=8.637, P=0.000),expression level of MAP1LC3-Ⅱ increased(t=7.101, P=0.000; t=7.656, P= 0.000; t=6.816, P=0.000; t=9.043, P=0.000),curcumin suppressed apoptotic activity by showing higher expression level of Bcl-2 (t=3.290, P=0.007),lower expression level of activited Caspase-3 (t=3.520, P= 0.005),lower expression level of P62 (t=3.595, P=0.004),and higher expression level of MAP1LC3-Ⅱ (t= 4.954, P=0.000). More tissue damage was seen 28d after TBI (t=34.813, P=0.000; t=11.172, P=0.000) but less tissue damage was seen in TBI+curcumin group (t=4.525, P=0.003). Conclusions Curcumin could inhibit neuronal apoptosis and enhance antophagic activity. Therefore,it may induce neuroprotection and promote nerual renovaion after fraumatic brain injury.

Keywords

• Craniocerebral trauma; Curcumin; Apoptosis; Disease models
• animal