[Mechanism of Wuyou Decoction in improving hippocampal injury in chronic sleep deprivation model rats by inhibiting neuroinflammation and protecting blood-brain barrier].

Chronic sleep deprivation for 21 days significantly impaired learning and memory in rats compared to normal controls.

• Model group rats exhibited significantly prolonged escape latency in the Morris water maze compared to the normal group.
• Model group rats showed decreased platform-crossing times and reduced target quadrant residence time.
• Fifty 2-month-old male SD rats were randomly divided into five groups: normal, model, low-dose WYD, medium-dose WYD, and high-dose WYD.
• The water platform sleep deprivation model involved a 7-day adaptation period followed by 21 days of formal sleep deprivation modeling.

Chronic sleep deprivation caused significant hippocampal neuronal damage, including reduced Nissl bodies and NeuN-positive neurons with disorganized arrangement.

• Nissl body count was reduced in the model group compared to the normal group.
• NeuN-positive neurons (assessed by immunohistochemistry) were decreased in the model group.
• Neuronal arrangement was disorganized in the model group hippocampus.
• Medium-dose WYD intervention resulted in more numerous Nissl bodies and neurons that were orderly arranged compared to the model group.

Chronic sleep deprivation elevated amyloid beta protein levels in hippocampal tissue, which were reduced by WYD treatment.

• Levels of Aβ1-40 and Aβ1-42 were elevated in the model group compared to the normal group as measured by ELISA.
• Medium-dose WYD intervention reduced both Aβ1-40 and Aβ1-42 levels compared to the model group.
• Elevated amyloid beta levels are associated with cognitive impairment and neurodegeneration.

Chronic sleep deprivation activated microglia and astrocytes in the hippocampus, as evidenced by increased IBA1 and GFAP fluorescence intensity.

• Fluorescence intensity of IBA1 (microglial marker) was increased in the model group compared to the normal group.
• Fluorescence intensity of GFAP (astrocyte marker) was increased in the model group compared to the normal group.
• Medium-dose WYD attenuated fluorescence intensity of both IBA1 and GFAP compared to the model group.
• IBA1 and GFAP levels were assessed by immunofluorescence.

Chronic sleep deprivation upregulated pro-inflammatory cytokines IL-1β, IL-6, and TNF-α in hippocampal tissue, which were decreased by WYD treatment.

• Expression of inflammatory factors IL-1β, IL-6, and TNF-α was enhanced in the model group compared to the normal group.
• Medium-dose WYD decreased levels of IL-1β, IL-6, and TNF-α compared to the model group.
• Inflammatory factor expression was analyzed by Western blot in hippocampal tissue.

Chronic sleep deprivation disrupted blood-brain barrier integrity by upregulating MMP2 and MMP9 and downregulating tight junction proteins ZO-1, occludin, and claudin 5.

• Expression of MMP9 and MMP2 was upregulated in the model group compared to the normal group.
• Expression of ZO-1, occludin, and claudin 5 was downregulated in the model group compared to the normal group.
• Medium-dose WYD downregulated MMP9 and MMP2 expression and upregulated ZO-1, occludin, and claudin 5 expression compared to the model group.
• BBB-related proteins were analyzed by Western blot in hippocampal tissue.

Medium-dose WYD administered for 28 consecutive days improved cognitive performance in chronic sleep-deprived rats across multiple Morris water maze measures.

• Medium-dose WYD intervention shortened escape latency compared to the model group.
• Medium-dose WYD increased platform-crossing times compared to the model group.
• Medium-dose WYD increased target quadrant residence time compared to the model group.
• WYD was administered via intragastric administration concurrently with the start of formal modeling for 28 consecutive days.