ObjectiveThis paper aims to investigate the effects of Xixintang on aquaporin-4 （AQP4） polarity distribution， blood-brain barrier （BBB） function， and neuroinflammationin rats with Alzheimer's disease （AD）， thereby revealing the potential mechanism through which this formula protects the BBB by regulating AQP4 polarization. The aim is to provide a scientific basis for clinical treatment. MethodsSixty Sprague-Dawley （SD） rats were randomly divided into a normal group， a model group， a probiotic group， a donepezil group， and an Xixintang group. The model was established by intraperitoneal injection of D-galactose （D-Gal） combined with bilateral intracerebroventricular injection of amyloid-β_25-35 （Aβ_25-35）. The probiotic group （30.85 mg·kg^-1）， donepezil group （0.88 mg·kg^-1）， and Xixintang group （1.174 g·kg^-1） received daily gavage administration， while the normal and model groups received intragastric administration with an equal volume of normal saline for one month. Cognitive ability was assessed by using the Morris water maze. BBB permeability was detected via Evans blue extravasation. The contents of interleukin-6 （IL-6）， amyloid-β_1-42 （Aβ_1-42）， and tumor necrosis factor-α （TNF-α） in the hippocampal tissues were measured by enzyme-linked immunosorbent assay （ELISA）. The protein expressions of zonula occludens-1 （ZO-1）， occludin， tissue inhibitor of metalloproteinase-1 （TIMP-1）， matrix metalloproteinase-9 （MMP-9）， and AQP4 in the hippocampal tissues were detected by western blot. The expression and co-localization levels of Aβ_1-42， ionized calcium-binding adapter molecule 1 （IBA1）， and AQP4/platelet endothelial cell adhesion molecule 31 （CD31） in the hippocampal region were examined by immunofluorescence. ResultsCompared with the normal group， the model group exhibited a significant decline in cognitive ability （P<0.01） and a marked increase in Evans blue extravasation in the brain （P<0.01）. The expressions of ZO-1， occludin， and TIMP-1 were significantly decreased （P<0.01）， while the expressions of AQP4 and MMP-9 were significantly increased （P<0.01）. The co-localization level of AQP4/CD31 was significantly reduced （P<0.01）， and the expressions of Aβ_1-42， IL-6， TNF-α， and IBA1 were significantly elevated （P<0.01）. Compared with the model group， the Xixintang group showed significant improvement in cognitive ability （P<0.01） and a significant reduction in Evans blue extravasation in the brain （P<0.01）. The expressions of occludin， TIMP-1， and ZO-1 were significantly increased （P<0.05， P<0.01）， while the expressions of AQP4 and MMP-9 were significantly decreased （P<0.05）. The co-localization level of AQP4/CD31 was significantly enhanced （P<0.01）， and the expressions of Aβ_1-42， IL-6， TNF-α， and IBA1 were significantly reduced （P<0.05， P<0.01）. ConclusionXixintang may improve cognitive function and alleviate AD pathology in AD model rats by regulating AQP4 polarity distribution， thereby breaking the vicious cycle of "Aβ deposition-neuroinflammation-BBB damage" and restoring the homeostasis of the microenvironment in the brain.

ObjectiveThis study aims to investigate whether Xixintang could ameliorate cognitive dysfunction in an Alzheimer's disease （AD） rat model induced by D-galactose and β-amyloid （Aβ_25-35）， by means of repairing the colonic mucosal barrier， regulating the Toll-like receptor 4 （TLR4）/nuclear factor-κB p65 （NF-κB p65） signaling pathway， and intervening in the pathological process mediated by the gut-brain axis. MethodsSixty specific pathogen-free （SPF） male Sprague-Dawley （SD） rats were randomly divided to five groups （n=12）： A control group， a model group， a donepezil group， an Xixintang group， and a probiotic group. Except for those in the control group， rats in all other groups received daily intraperitoneal injections of D-galactose for six consecutive weeks. Subsequently， aggregated Aβ_25-35 was injected stereotactically into the bilateral ventricles to establish the AD model. During the intervention periods， the rats in all groups were administered their respective drugs and normal saline by gavage. The Morris water maze test was used to assess the capacity for spatial learning and memory. Hematoxylin-eosin （HE） staining was employed to observe the histopathological changes in the colon tissues. Immunofluorescence was used to detect Aβ_1-41 deposition in the hippocampal region and Mucin 2 （MUC2） expression in the colonic mucosa. Western blot was performed to measure the protein expression levels of FFAR2，TLR4， NF-κB p65， occludin （OCLN）， zonula occludens-1 （ZO-1）， and MUC2 in the colonic tissues. Enzyme-linked immunosorbent assay （ELISA） was used to determine the contents of interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， serum amyloid A （SAA）， and Aβ_1-42 in the hippocampal region from the colonic tissues. The lipopolysaccharide （LPS） concentrations in colon tissues of rats were measured by using a dynamic chromogenic limulus assay. ResultsCompared with those in the control group， the rats in the model group exhibited a significantly prolonged escape latency and a markedly shorter duration in the target quadrant （P<0.01）. The integrity of the colonic mucosal structure was compromised， with disordered gland arrangement and a reduced number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was significantly increased （P<0.01）. The protein expression levels of TLR4 and NF-κB p65 in colonic tissues were significantly upregulated （P<0.01）， while those of occludin and ZO-1 were downregulated （P<0.01）. The contents of inflammatory factors such as IL-6， TNF-α， and SAA were significantly elevated （P<0.01）， and the LPS level in the serum was markedly increased （P<0.01）. In comparison to those in the model group， the rats in the Xixintang group showed a significantly shortened escape latency and a prolonged duration in the target quadrant （P<0.01）. The colonic mucosal structure was ameliorated， with neat gland arrangement and an increased number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was reduced （P<0.01）. The protein expressions of TLR4 and NF-κB p65 in the colon tissues were decreased （P<0.05，P<0.01）， while the protein levels of occludin and ZO-1 were increased （P<0.01）. The contents of IL-6， TNF-α， and serum amyloid A （SAA） were decreased （P<0.01）， and the LPS level was reduced （P<0.01）. ConclusionXixintang can significantly ameliorate cognitive dysfunction of AD model rats， by means of restoring the colonic mucosal barrier structure， reducing cerebral Aβ deposition， and suppressing peripheral and central inflammatory response. Its mechanism of action may be closely associated with the suppression of the TLR4/NF-κB signaling pathway activation， reduction of endotoxin levels， and regulation of the gut-brain axis.

ObjectiveThis study aims to investigate whether Xixintang could ameliorate cognitive dysfunction in an Alzheimer's disease （AD） rat model induced by D-galactose and β-amyloid （Aβ_25-35）， by means of repairing the colonic mucosal barrier， regulating the Toll-like receptor 4 （TLR4）/nuclear factor-κB p65 （NF-κB p65） signaling pathway， and intervening in the pathological process mediated by the gut-brain axis. MethodsSixty specific pathogen-free （SPF） male Sprague-Dawley （SD） rats were randomly divided to five groups （n=12）： A control group， a model group， a donepezil group， an Xixintang group， and a probiotic group. Except for those in the control group， rats in all other groups received daily intraperitoneal injections of D-galactose for six consecutive weeks. Subsequently， aggregated Aβ_25-35 was injected stereotactically into the bilateral ventricles to establish the AD model. During the intervention periods， the rats in all groups were administered their respective drugs and normal saline by gavage. The Morris water maze test was used to assess the capacity for spatial learning and memory. Hematoxylin-eosin （HE） staining was employed to observe the histopathological changes in the colon tissues. Immunofluorescence was used to detect Aβ_1-41 deposition in the hippocampal region and Mucin 2 （MUC2） expression in the colonic mucosa. Western blot was performed to measure the protein expression levels of FFAR2，TLR4， NF-κB p65， occludin （OCLN）， zonula occludens-1 （ZO-1）， and MUC2 in the colonic tissues. Enzyme-linked immunosorbent assay （ELISA） was used to determine the contents of interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， serum amyloid A （SAA）， and Aβ_1-42 in the hippocampal region from the colonic tissues. The lipopolysaccharide （LPS） concentrations in colon tissues of rats were measured by using a dynamic chromogenic limulus assay. ResultsCompared with those in the control group， the rats in the model group exhibited a significantly prolonged escape latency and a markedly shorter duration in the target quadrant （P<0.01）. The integrity of the colonic mucosal structure was compromised， with disordered gland arrangement and a reduced number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was significantly increased （P<0.01）. The protein expression levels of TLR4 and NF-κB p65 in colonic tissues were significantly upregulated （P<0.01）， while those of occludin and ZO-1 were downregulated （P<0.01）. The contents of inflammatory factors such as IL-6， TNF-α， and SAA were significantly elevated （P<0.01）， and the LPS level in the serum was markedly increased （P<0.01）. In comparison to those in the model group， the rats in the Xixintang group showed a significantly shortened escape latency and a prolonged duration in the target quadrant （P<0.01）. The colonic mucosal structure was ameliorated， with neat gland arrangement and an increased number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was reduced （P<0.01）. The protein expressions of TLR4 and NF-κB p65 in the colon tissues were decreased （P<0.05，P<0.01）， while the protein levels of occludin and ZO-1 were increased （P<0.01）. The contents of IL-6， TNF-α， and serum amyloid A （SAA） were decreased （P<0.01）， and the LPS level was reduced （P<0.01）. ConclusionXixintang can significantly ameliorate cognitive dysfunction of AD model rats， by means of restoring the colonic mucosal barrier structure， reducing cerebral Aβ deposition， and suppressing peripheral and central inflammatory response. Its mechanism of action may be closely associated with the suppression of the TLR4/NF-κB signaling pathway activation， reduction of endotoxin levels， and regulation of the gut-brain axis.

ObjectiveTo investigate the effects of Xixintang （XXT）-medicated serum on the amyloid β-protein （Aβ）_25-35-induced polarization of BV-2 microglial cells by a cell experiment and uncover the potential mechanisms of this formula in the prevention and treatment of Alzheimer's disease （AD）， thus providing scientific evidence for the clinical application of XXT. MethodsBV-2 microglial cells were subcultured. The optimal concentrations of XXT-medicated serum and Aβ_25-35 were determined via the cell-counting kit-8 （CCK-8） assay. The cell experiment was carried out with the following groups： blank control， model （Aβ_25-35 at 40 μmol·L^-1）， XXT-medicated serum （Aβ_25-35 at 40 μmol·L^-1 + 10% XXT-medicated serum）， and blank serum （Aβ_25-35 at 40 μmol·L^-1 + 10% blank serum）. After 24 hours of cell incubation， immunofluorescence was used to detect the expression of ionized calcium-binding adaptor molecule 1 （IBA1）， CD16/32， and CD206. Real-time PCR was performed to measure the mRNA levels of CD206， CD163， inducible nitric oxide synthase （iNOS）， and arginase 1 （Arg-1）. Enzyme-linked immunosorbent assay （ELISA） was employed to quantify the levels of nerve growth factor （NGF）， iNOS， and Arg-1. The nitric oxide （NO） concentration was determined via the nitrate reductase method. ResultsCompared with the blank control group， the model group showed increased expression of IBA1 and CD16/32 （P<0.01）， decreased expression of CD206 （P<0.05）， upregulation in the mRNA level （P<0.01） and content （P<0.05） of iNOS， downregulation in the mRNA levels of CD206， CD163， and Arg-1 （P<0.05， P<0.01）， lowered levels of Arg-1 and NGF （P<0.05）， and an elevation in the NO level （P<0.05）. Compared with the model group， the XXT-medicated serum group exhibited reduced expression of IBA1 and CD16/32 （P<0.05， P<0.01） and increased expression of CD206 （P<0.01）. Both the content and mRNA level of iNOS were downregulated （P<0.05， P<0.01）， while the mRNA levels of CD206， CD163， and Arg-1 were upregulated （P<0.01） in the XXT-medicated serum group. In addition， the XXT-medicated serum group showed elevated levels of Arg-1 and NGF （P<0.05） and a lowered level of NO （P<0.05）. The blank serum group showed no statistically significant differences in the measured parameters compared with the model group. ConclusionThe XXT-medicated serum can inhibit the polarization toward the M1 phenotype and promote the polarization toward the M2 phenotype， exerting anti-inflammatory and neurotrophic effects.

ObjectiveTo explore the potential mechanism of Xixin Decoction （洗心汤， XD） in treating Alzheimer's disease （AD）. MethodsXD-containing serum was prepared， and the BV-2 microglial cell viability was assessed using the CCK8 assay to determine the optimal intervention concentrations of XD-containing serum and amyloid-beta _25-35 （Aβ_25-35） for subsequent experiments. BV-2 cells were divided into four groups， control group， model group （Aβ_25-35）， XD-containing serum group （Aβ_25-35+ XD-containing serum）， and blank serum group （Aβ_25-35 + blank serum）. After 24 hours of culture， the levels of interleukin-1β（IL-1β）， cyclooxygenase-2 （COX-2）， and arginase-2 （Arg-2） in the supernatent were detected by ELISA. Immunofluorescence staining was performed to detect the protein levels of ionized calcium-binding adaptor molecule 1 （IBA1）， CD86， and CD206. RT-PCR was used to analyze the mRNA expression of IL-1β， interleukin-6 （IL-6）， and interleukin-10 （IL-10）. ResultsThe concentrations of 10% XD-containing serum and 40 μmol·L^-¹ Aβ_25-35 were selected for subsequent experiments. Compared to the control group， the model group showed significantly increased levels of IL-1β and COX-2 in the supernatant， as well as elevated protein expression of IBA1 and CD86 and increased mRNA expression of IL-1β and IL-6， while exhibiting significantly reduced levels of Arg-2 in the supernatant， CD206 protein expression， and IL-10 mRNA expression （P＜0.05 or P＜0.01）. Compared to the model group， the XD-containing serum group showed significant improvement in all these indicators （P＜0.01）， whereas no statistically significant differences were observed in the blank serum group （P＞0.05）. ConclusionXD may regulate microglial activation， inhibit pro-inflammatory factors， and enhance anti-inflammatory factor release， thereby improving neuroimmune inflammation and inhibiting the progression of Alzheimer's disease.

Objective:To study the effects of Shengui Jiajian Pills on myocardial fibrosis and the transforming growth factor-β1 (TGF-β1)/Smads signaling pathway in elderly rats with hypothyroidism; To preliminarily explore the mechanism of Shengui Jiajian Pills in treating hypothyroid heart disease through the TGF-β1/Smads pathway.Methods:Totally 60 SD rats were randomly divided into normal group, model group, sodium levothyroxine group, and Shengui Jiajian Pills low-, medium-, and high-dosage groups, with 10 rats in each group. A model of elderly hypothyroid heart injury in rats was prepared by freely drinking 0.1% propylthiouracil (PTU) for 10 weeks. Each group of rats was gavaged with the corresponding drug once a day for 6 weeks. After the last gastric lavage, an electrocardiogram was performed, hematoxylin-eosin staining (HE) was used to observe pathological changes in the heart tissue; bitter acid-toluidine blue staining was used to detect fibrosis of the heart tissue; TUNEL staining was used to observe myocardial cell apoptosis; Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of thyroid stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4) in the serum, as well as brain natriuretic peptide (BNP), creatine kinase isoenzymes MB (CK-MB), and lactate dehydrogenase (LDH); Western blot was used to detect the relative expressions of TGF-β1, p-Smad2, p-Smad3, α-smooth muscle actin (α-SMA), matrix metalloproteinase-1 (MMP-1), TIMP1, Bax, and Caspase-3 in the heart tissue; and immunofluorescence was used to detect the positive expressions of TGF-β1, Smad3, α-SMA, and MMP-1 in the heart tissue.Results:Compared with the model group, the inflammatory cell infiltration and cell damage in the heart of rats in each dosage group of Shengui Jiajian Pills were improved, the myocardial fibrosis area ratio was significantly reduced ( P<0.05), and the myocardial cell apoptosis rate significantly decreased ( P<0.05), the levels of TSH, BNP, CLD, and HK-MB in serum significantly decreased ( P<0.05). The levels of FT3 and FT4 increased in the Shengui Jiajian Pills medium- and high-dosage groups ( P<0.05), while the positive expressions of TGF-β1, Smad3, α-SMA, and MMP-1 decreased ( P<0.05). The protein expression of TGF-β1, p-Smad3, MMP-1, Bax, and Caspase-3 decreased ( P<0.05), and the expression of TIMP-1 increased ( P<0.05). The expression of Smad7 increased in the Shengui Jiajian Pills medium-dosage group ( P<0.05). Conclusion:Shengui Jiajian Pills may reduce myocardial collagen fiber deposition by modulating the TGF-β1/Smad3 signaling pathway, thereby partially reversing the pathological features of hypothyroidism-induced myocardial injury, with more pronounced effects observed in the medium and high dosage groups.