ObjectiveTo explore the effects of different dosage forms of Kaixinsan （KXS） on the morphology and function of mitochondria in rat models of Alzheimer's disease （AD） and potential mechanisms of action. MethodsMale SD rats were randomly assigned to a sham group， model group， treatment groups receiving KXS decoction， powders， and granules （3.08 g·kg^-1）， as well as donepezil group （0.51×10^-3 g·kg^-1）， with 10 rats in each group. AD model was created using intracerebroventricular injection of streptozocin （STZ）. After 30 days of administration， behavioral assessments were conducted， and mitochondrial morphology was observed using transmission electron microscopy. Mitochondrial respiratory chain complex content was measured via enzyme-linked immunosorbent assay （ELISA）. Changes in mitochondrial membrane potential were measured via JC-1 staining， and superoxide dismutase （SOD） activity and reactive oxygen species （ROS） levels were measured via biochemical assays. The mRNA expression of adenosine 5'-monophosphate-activated protein kinase （AMPK）， peroxisome proliferator-activated receptor gamma coactivator-1α （PGC-1α）， and silent information regulator 3 （SIRT3） was detected by real-time fluorescent quantitative polymerase chain reaction （Real-time PCR）， and Western blot was used to examine the protein expression levels of optic atrophy protein1 （OPA1）， mitochondrial fission protein 1 （FIS1）， AMPK， p-AMPK， PGC-1α， and SIRT3. ResultsCompared with the sham group， rats in the model group had significantly lower recognition index， spontaneous alternation rate， escape latency， number of platform crossings， time spent in the target quadrant， and percentage of distance traveled in the target quadrant distance （P<0.05， P<0.01）. Significant mitochondrial damage was observed in the hippocampal tissue， with a marked decrease in mitochondrial respiratory chain complex content （P<0.01） and reduced mitochondrial membrane potential （P<0.05）. Additionally， the SOD activity was reduced， while ROS levels were elevated （P<0.01）. The mRNA expression of PGC-1α and SIRT3 was significantly downregulated （P<0.01）， along with decreased protein expression levels of OPA1， p-AMPK/AMPK， PGC-1α， and SIRT3， whereas FIS1 protein expression was significantly upregulated （P<0.05， P<0.01）. Compared with the model group， rats in KXS-treated groups （various dosage forms） showed significant improvement in behavioral indexes （P<0.05， P<0.01）， reduced hippocampal mitochondrial damage， and more organized mitochondrial cristae. Mitochondrial respiratory chain complex content was significantly increased （P<0.05， P<0.01）， and mitochondrial membrane potentials were elevated （P<0.05）. SOD activity was elevated， and ROS levels were significantly reduced （P<0.05， P<0.01）. Furthermore， the mRNA expression of PGC-1α and SIRT3 was upregulated， with increased protein levels of OPA1， p-AMPK/AMPK， PGC-1α， and SIRT3， while FIS1 protein expression levels were significantly reduced （P<0.05， P<0.01）. Across the KXS-treated groups， the granule group showed a higher spontaneous alternation rate than the decoction and powder groups （P<0.05）. ConclusionKXS decoction， powders， and granules can improve the learning and memory ability of rats， with granules being the most effective. The mechanism of action may involve activation of the AMPK/PGC-1α/SIRT3 signaling pathway， improvement of the mitochondrial function， and subsequent amelioration of the brain energy metabolism disorders.

ObjectiveTo explore the effects of different dosage forms of Kaixinsan （KXS） on the morphology and function of mitochondria in rat models of Alzheimer's disease （AD） and potential mechanisms of action. MethodsMale SD rats were randomly assigned to a sham group， model group， treatment groups receiving KXS decoction， powders， and granules （3.08 g·kg^-1）， as well as donepezil group （0.51×10^-3 g·kg^-1）， with 10 rats in each group. AD model was created using intracerebroventricular injection of streptozocin （STZ）. After 30 days of administration， behavioral assessments were conducted， and mitochondrial morphology was observed using transmission electron microscopy. Mitochondrial respiratory chain complex content was measured via enzyme-linked immunosorbent assay （ELISA）. Changes in mitochondrial membrane potential were measured via JC-1 staining， and superoxide dismutase （SOD） activity and reactive oxygen species （ROS） levels were measured via biochemical assays. The mRNA expression of adenosine 5'-monophosphate-activated protein kinase （AMPK）， peroxisome proliferator-activated receptor gamma coactivator-1α （PGC-1α）， and silent information regulator 3 （SIRT3） was detected by real-time fluorescent quantitative polymerase chain reaction （Real-time PCR）， and Western blot was used to examine the protein expression levels of optic atrophy protein1 （OPA1）， mitochondrial fission protein 1 （FIS1）， AMPK， p-AMPK， PGC-1α， and SIRT3. ResultsCompared with the sham group， rats in the model group had significantly lower recognition index， spontaneous alternation rate， escape latency， number of platform crossings， time spent in the target quadrant， and percentage of distance traveled in the target quadrant distance （P<0.05， P<0.01）. Significant mitochondrial damage was observed in the hippocampal tissue， with a marked decrease in mitochondrial respiratory chain complex content （P<0.01） and reduced mitochondrial membrane potential （P<0.05）. Additionally， the SOD activity was reduced， while ROS levels were elevated （P<0.01）. The mRNA expression of PGC-1α and SIRT3 was significantly downregulated （P<0.01）， along with decreased protein expression levels of OPA1， p-AMPK/AMPK， PGC-1α， and SIRT3， whereas FIS1 protein expression was significantly upregulated （P<0.05， P<0.01）. Compared with the model group， rats in KXS-treated groups （various dosage forms） showed significant improvement in behavioral indexes （P<0.05， P<0.01）， reduced hippocampal mitochondrial damage， and more organized mitochondrial cristae. Mitochondrial respiratory chain complex content was significantly increased （P<0.05， P<0.01）， and mitochondrial membrane potentials were elevated （P<0.05）. SOD activity was elevated， and ROS levels were significantly reduced （P<0.05， P<0.01）. Furthermore， the mRNA expression of PGC-1α and SIRT3 was upregulated， with increased protein levels of OPA1， p-AMPK/AMPK， PGC-1α， and SIRT3， while FIS1 protein expression levels were significantly reduced （P<0.05， P<0.01）. Across the KXS-treated groups， the granule group showed a higher spontaneous alternation rate than the decoction and powder groups （P<0.05）. ConclusionKXS decoction， powders， and granules can improve the learning and memory ability of rats， with granules being the most effective. The mechanism of action may involve activation of the AMPK/PGC-1α/SIRT3 signaling pathway， improvement of the mitochondrial function， and subsequent amelioration of the brain energy metabolism disorders.