Chaihu Shugan Decoction improves cognitive impairment after epilepsy in rats by regulating hippocampal NMDAR subunits via upregulating ASIC1

doi:10.12122/j.issn.1673-4254.2025.07.17

Abstract

Abstract:

Objective To explore the therapeutic mechanism of Chaihu Shugan (CHSG) Decoction for improving cognitive impairment in rats with epilepsy induced by lithium chloride and pilocarpine. Methods Male SD rat models of cognitive impairment model after epilepsy induced by intraperitoneal injection with lithium chloride and pilocarpine were randomly divided into 5 groups (n=12) for treatment with daily gavage of saline, donepezil (90 mg/kg), or CHSG Decoction at 2.5, 5.0, 10, 20 and 40 g/kg for 4 consecutive weeks, with 10 rats with intraperitoneal injection with saline as the blank control group. Morris water maze test was used to evaluate cognitive and behavioral changes of the rats after treatment. The mRNA and protein expressions of ASIC1, NR1, NR2A and NR2B in the hippocampus of rats were detected using RT-qPCR and Western blotting. Results Compared with those with saline treatment, the rat models treated with CHSG Decoction at 5 and 10 g/kg showed significantly shortened escape latency and prolonged stay in the target quadrant with increased number of platform crossings in Morris water maze test. CHSG Decoction treatment at the two doses significantly increased ASIC1, NR1, NR2A and NR2B protein expressions in the hippocampus of the rat models, and their mRNA expression levels were all increased significantly after the treatment at the doses above 2.5 g/kg. Conclusion CHSG Decoction can improve cognitive impairment in rats after epilepsy possibly by regulating the expression and channel activity of NMDAR protein and its subunit protein via upregulating ASIC1 to modulate neuronal excitability and synaptic plasticity in the hippocampus.

Key words: epilepsy, cognitive impairment, treatment from Gan, Chaihu Shugan Decoction, acid sensitive ion channel, NMDAR

Yunhong YU, Wei XIE, Hui LI. Chaihu Shugan Decoction improves cognitive impairment after epilepsy in rats by regulating hippocampal NMDAR subunits via upregulating ASIC1[J]. Journal of Southern Medical University, 2025, 45(7): 1506-1512.

Figures/Tables 6

Tab.1 Reaction system of RT-qPCR

Component	Quantity (μL)
RNase Free d H₂O	10
5×PrimeScript^TM Buffer (for real time)	2
PrimeScript^TMRT Enzyme Mix I	1
Oligo dT Primer (50 μmol/L)	1
Random 6 mers (100 μmol/L)	2
RNA	4
Total	20

Tab.2 Primer sequence for RT-qPCR

Gene name	Sequence (5'-3')	Length (bp)
ASIC1	GCAATCTCAATGAGTTCCGCT	107
ASIC1	CTGTGTGTCCGGGATCTCATA
NR1	AGGACTGTCAGTTCATGTGGT	101
NR1	CATCTTCCTCCTCCTCAC
NR2A	GCTCATCCCCAAAGAGTTTCC	99
NR2A	AAGATCCCAAGACCGTCTCTC
NR2B	CAGCAAAGCTCGTTCCCAAA	91
NR2B	GGCGTCTTTTATGGCCACTTC
GAPDH	GTATGACTCTACCCACGGCAAGT	99
GAPDH	TCTCGCTCCTGGAAGATGGT

Fig.1 Cognitive and behavioral changes of the rats assessed using Morris water maze test. **P<0.01 vs Control group; #P<0.05, ##P<0.01 vs Model group; &P<0.05, &&P<0.01 vs CHSG-3 group.

Fig.2 Expression of ASIC1, NR1, NR2A, and NR2B proteins in the hippocampus of the rats detected by Western blotting. 1: Control group; 2: Model group; 3: CHSG-1 group; 4: CHSG-2 group; 5: CHSG-3 group; 6: CHSG-4 group; 7: CHSG-5 group; 8: Positive control group.

Fig. 3 Expression levels of ASIC1, NR1, NR2A and NR2B protein in each group. **P<0.01 vs Control group; #P<0.05, ##P<0.01 vs Model group; &P<0.05, &&P<0.01 vs CHSG-3 group.

Fig.4 Expression levels of ASIC1, NR1, NR2A and NR2B mRNA in each group. **P<0.01 vs Control group; ##P<0.01 vs Model group.

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