Effect of Suanzaoren Tang on Learning-memory Function and NLRP3 Pathway in Sleep-deprived Rats / 中国实验方剂学杂志

Objective:To explore the mechanism of Suanzaoren Tang in improving learning-memory of sleep-deprived rats based on Nod-like receptor 3 （NLRP3） inflammatome pathway. Method:The rats were randomly divided into normal control group， model group， Eszolam group（5.4×10^-4 g·kg^-1·d^-1）， low-dose Suanzaoren Tang group（4.59 g·kg^-1·d^-1）and high-dose Suanzaoren Tang group （18.36 g·kg^-1·d^-1）. In addition to normal control group， other groups were used to constructed sleep-deprived model， which was concurrent with 30-day continuous drug administration. Water maze was used to evaluate the learning-memory function of rats； The mRNA and protein expressions of NLRP3， apoptosis-related speckle proteins （ASC）， aspartic acid-specific cysteine protease-1 （Caspase-1）， interleukin-1（IL-1） and IL-18 in the hippocampus of rats were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. Result:Compared with control group， the incubation period of the platform， the total distance of swimming and the duration of first reaching the platform in model group were significantly increased （<italic>P</italic><0.01）， while the number of platform crossings and the target quadrant time were decreased （<italic>P</italic><0.01）. Compared with the model group， the incubation period， total swimming distance and the duration of first reaching the platform in low-dose Suanzaoren Tang group and high-dose Suanzaoren Tang group were decreased to different degrees （<italic>P</italic><0.05，<italic>P</italic><0.01）， while the number of platform crossings and the target quadrant time were increased significantly （<italic>P</italic><0.05，<italic>P</italic><0.01），but with no significant change in estazolam group. Compared with normal control group， mRNA and protein expressions of NLRP3， ASC， Caspase-1， IL-1<italic>β</italic>， IL-18 in the hippocampus of the model group were significantly increased （<italic>P</italic><0.05，<italic>P</italic><0.01）. Compared with model group， mRNA and protein expressions of NLRP3， ASC， Caspase-1， IL-1<italic>β</italic> and IL-18 in the hippocampus of the rats in low-dose Suanzaoren Tang group and high-dose Suanzaoren Tang group were all decreased to different degrees （<italic>P</italic><0.05）. The mRNA and protein expressions of NLRP3， ASC， Caspase-1， IL-1<italic>β</italic> and IL-18 in the hippocampus of Suanzaoren group also decreased， but with no significant change. Conclusion:Suanzaoren Tang can improve the learning-memory function of sleep-deprived rats， and its mechanism is related to the inhibition of NLRP3 inflammatome pathway in hippocampus and the alleviation of neuroinflammation.

Effect of Suanzaoren Tang on Learning Memory and TLR4/NF-κB Signaling Pathway in Rats with Chronic Sleep Deprivation / 中国实验方剂学杂志

Objective::To explore the mechanism of Suanzaoren Tang in improving learning and memory impairment induced by sleep deprivation based on Toll-like receptor (TLR4)/nuclear transcription factor-κB (NF-κB) signaling pathway. Method::The experimental rats were randomly divided into blank group, model group, melatonin group (2.5×10-4 g·kg-1·d-1) and Suanzaoren Tang group (12.96 g·kg-1·d-1). Except the blank group, the chronic sleep deprivation model was established in other groups. After 28 days of continuous administration, the learning and memory of the rats were assessed by Morris water maze. The expressions of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α(TNF-α)in serum were detected by enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of TLR4, NF-κB p65 and nuclear transcription factor inhibitory protein α (IκBα) in the hippocampus of rats were detected by real-time fluorescence quantitative polymerase chain reaction (Real-time PCR), and the protein expressions of TLR4, IκBα, p-IκBα and NF-κB p65 in the hippocampus of rats were detected by immunohistochemistry (IHC). Result::Compared with the blank group, the platform latency, total swimming distance and the first landing time of the model group increased significantly (P<0.01), while the number of crossing platforms and target quadrant time decreased significantly (P<0.01). Compared with the model group, the platform latency, total swimming distance and the first platform time were reduced in the melatonin group and the Suanzaoren group (P<0.05, P<0.01), while the number of crossing platforms and target quadrants time were increased(P<0.05, P<0.01). Compared with the blank group, the expression levels of TNF-α, IL-1β and IL-6 in the model group were significantly increased (P<0.01). Compared with the model group, the levels of TNF-α, IL-1β and IL-6 in the serum of melatonin group and Suanzaoren Tang group decreased (P<0.05, P<0.01). Compared with the blank group, mRNA and protein expression levels of TLR4 and NF-κB p65 in the hippocampus of the model group were increased (P<0.01), while mRNA and protein expression levels of IκBα were decreased (P<0.01). Compared with the model group, the mRNA and protein expressions of TLR4 and NF-κB p65 in the hippocampus of melatonin group and Suanzaoren Tang group decreased (P<0.05, P<0.01), while the mRNA and protein expression levels of IκBα increased (P<0.05, P<0.01). Compared with the blank group, the protein expression level of p-IκBα in the hippocampus of the model group was significantly increased (P<0.01). Compared with the model group, the protein expression level of IκBα in the hippocampus of melatonin group and Suanzaoren Tang group was increased (P<0.05, P<0.01). Conclusion::Suanzaoren Tang can improve learning and memory impairment induced by sleep deprivation in rats, and its mechanism may be related to its inhibition of TLR4/NF-κB signaling pathway in hippocampus.