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1.
Braz. j. biol ; 83: e250179, 2023. graf
Article in English | LILACS, VETINDEX | ID: biblio-1339372

ABSTRACT

Abstract Diabetes mellitus (DM) is a non-communicable disease throughout the world in which there is persistently high blood glucose level from the normal range. The diabetes and insulin resistance are mainly responsible for the morbidities and mortalities of humans in the world. This disease is mainly regulated by various enzymes and hormones among which Glycogen synthase kinase-3 (GSK-3) is a principle enzyme and insulin is the key hormone regulating it. The GSK-3, that is the key enzyme is normally showing its actions by various mechanisms that include its phosphorylation, formation of protein complexes, and other cellular distribution and thus it control and directly affects cellular morphology, its growth, mobility and apoptosis of the cell. Disturbances in the action of GSK-3 enzyme may leads to various disease conditions that include insulin resistance leading to diabetes, neurological disease like Alzheimer's disease and cancer. Fluoroquinolones are the most common class of drugs that shows dysglycemic effects via interacting with GSK-3 enzyme. Therefore, it is the need of the day to properly understand functions and mechanisms of GSK-3, especially its role in glucose homeostasis via effects on glycogen synthase.


Resumo O diabetes mellitus (DM) é uma doença não transmissível em todo o mundo, na qual existe nível glicêmico persistentemente alto em relação à normalidade. O diabetes e a resistência à insulina são os principais responsáveis ​​pelas morbidades e mortalidades de humanos no mundo. Essa doença é regulada principalmente por várias enzimas e hormônios, entre os quais a glicogênio sintase quinase-3 (GSK-3) é uma enzima principal e a insulina é o principal hormônio que a regula. A GSK-3, que é a enzima-chave, normalmente mostra suas ações por vários mecanismos que incluem sua fosforilação, formação de complexos de proteínas e outras distribuições celulares e, portanto, controla e afeta diretamente a morfologia celular, seu crescimento, mobilidade e apoptose do célula. Perturbações na ação da enzima GSK-3 podem levar a várias condições de doença que incluem resistência à insulina que leva ao diabetes, doenças neurológicas como a doença de Alzheimer e câncer. As fluoroquinolonas são a classe mais comum de drogas que apresentam efeitos disglicêmicos por meio da interação com a enzima GSK-3. Portanto, é necessário hoje em dia compreender adequadamente as funções e mecanismos da GSK-3, principalmente seu papel na homeostase da glicose via efeitos na glicogênio sintase.


Subject(s)
Humans , Insulin Resistance , Diabetes Mellitus , Glycogen Synthase Kinase 3 , Glucose , Homeostasis
2.
Acta Pharmaceutica Sinica B ; (6): 1225-1239, 2022.
Article in English | WPRIM | ID: wpr-929366

ABSTRACT

The dysregulation of transcription factors is widely associated with tumorigenesis. As the most well-defined transcription factor in multiple types of cancer, c-Myc can transform cells by transactivating various downstream genes. Given that there is no effective way to directly inhibit c-Myc, c-Myc targeting strategies hold great potential for cancer therapy. In this study, we found that WSB1, which has a highly positive correlation with c-Myc in 10 cancer cell lines and clinical samples, is a direct target gene of c-Myc, and can positively regulate c-Myc expression, which forms a feedforward circuit promoting cancer development. RNA sequencing results from Bel-7402 cells confirmed that WSB1 promoted c-Myc expression through the β-catenin pathway. Mechanistically, WSB1 affected β-catenin destruction complex-PPP2CA assembly and E3 ubiquitin ligase adaptor β-TRCP recruitment, which inhibited the ubiquitination of β-catenin and transactivated c-Myc. Of interest, the effect of WSB1 on c-Myc was independent of its E3 ligase activity. Moreover, overexpressing WSB1 in the Bel-7402 xenograft model could further strengthen the tumor-driven effect of c-Myc overexpression. Thus, our findings revealed a novel mechanism involved in tumorigenesis in which the WSB1/c-Myc feedforward circuit played an essential role, highlighting a potential c-Myc intervention strategy in cancer treatment.

3.
Acta Pharmaceutica Sinica B ; (6): 1041-1053, 2022.
Article in English | WPRIM | ID: wpr-929344

ABSTRACT

The immune checkpoint blockade (ICB) targeting on PD-1/PD-L1 has shown remarkable promise in treating cancers. However, the low response rate and frequently observed severe side effects limit its broad benefits. It is partially due to less understanding of the biological regulation of PD-L1. Here, we systematically and comprehensively summarized the regulation of PD-L1 from nuclear chromatin reorganization to extracellular presentation. In PD-L1 and PD-L2 highly expressed cancer cells, a new TAD (topologically associating domain) (chr9: 5,400,000-5,600,000) around CD274 and CD273 was discovered, which includes a reported super-enhancer to drive synchronous transcription of PD-L1 and PD-L2. The re-shaped TAD allows transcription factors such as STAT3 and IRF1 recruit to PD-L1 locus in order to guide the expression of PD-L1. After transcription, the PD-L1 is tightly regulated by miRNAs and RNA-binding proteins via the long 3'UTR. At translational level, PD-L1 protein and its membrane presentation are tightly regulated by post-translational modification such as glycosylation and ubiquitination. In addition, PD-L1 can be secreted via exosome to systematically inhibit immune response. Therefore, fully dissecting the regulation of PD-L1/PD-L2 and thoroughly detecting PD-L1/PD-L2 as well as their regulatory networks will bring more insights in ICB and ICB-based combinational therapy.

4.
Article in English | WPRIM | ID: wpr-928959

ABSTRACT

OBJECTIVE@#To study the effects of total ginsenosides (TG) extract from Panax ginseng on neural stem cell (NSC) proliferation and differentiation and their underlying mechanisms.@*METHODS@#The migration of NSCs after treatment with various concentrations of TG extract (50, 100, or 200 µ g/mL) were monitored. The proliferation of NSCs was examined by a combination of cell counting kit-8 and neurosphere assays. NSC differentiation mediated by TG extract was evaluated by Western blotting and immunofluorescence staining to monitor the expression of nestin and microtubule associated protein 2 (MAP2). The GSK-3β/β-catenin pathway in TG-treated NSCs was examined by Western blot assay. The NSCs with constitutively active GSK-3β mutant were made by adenovirus-mediated gene transfection, then the proliferation and differentiation of NSCs mediated by TG were further verified.@*RESULTS@#TG treatment significantly enhanced NSC migration (P<0.01 or P<0.05) and increased the proliferation of NSCs (P<0.01 or P<0.05). TG mediation also significantly upregulated MAP2 expression but downregulated nestin expression (P<0.01 or P<0.05). TG extract also significantly induced GSK-3β phosphorylation at Ser9, leading to GSK-3β inactivation and, consequently, the activation of the GSK-3β/β-catenin pathway (P<0.01 or P<0.05). In addition, constitutive activation of GSK-3β in NSCs by the transfection of GSK-3β S9A mutant was found to significantly suppress TG-mediated NSC proliferation and differentiation (P<0.01 or P<0.05).@*CONCLUSION@#TG promoted NSC proliferation and neuronal differentiation by inactivating GSK-3β.


Subject(s)
Animals , Cell Differentiation , Cell Proliferation , Ginsenosides/pharmacology , Glycogen Synthase Kinase 3 beta/metabolism , Neural Stem Cells/metabolism , Panax , Plant Extracts/pharmacology , Rats , beta Catenin/metabolism
5.
Article in Chinese | WPRIM | ID: wpr-927893

ABSTRACT

Objective: To investigate the effects of glycogen synthase kinase-3β (GSK3β)/eukaryotic extension factor kinase 2 (eEF2K) signaling pathway on the process of pulmonary fibrosis through in vivo experiments, and find new ideas for clinical treatment of pulmonary fibrosis. Methods: The pulmonary fibrosis model of C57BL/6 male mice was induced by bleomycin with intratracheal injection at the dose of 2 mg/kg. After 14 days of modeling, animals were divided into model group, negative inhibition group and inhibition group (n=5 for each group), and control group was not processed. The inhibition group was treated with TDZD-8 (4 mg/kg) after modeling, the negative inhibition group was given DMSO solution after modeling, and the samples were collected after 28 days. Hematoxylin-eosin staining method was used to detect lung fibrosis in mice and scored according to Ashcroft scale. Expression levels of GSK3β, p-GSK3β, eEF2K, p-eEF2K (Ser70, Ser392, Ser470), precursor protein of matrix metalloproteinase-2 (pro-MMP-2), matrix metalloproteinase-2 (MMP-2), collagen I (Col I), collagen Ⅲ (Col Ⅲ) and α-smooth muscle actin (α-SMA) were detected by Western blot. Results: Compared with control group, the fibrosis score was up-regulated, the expression levels of GSK3β, p-GSK3β, p-eEF2K (Ser70, Ser392, Ser470), pro-MMP-2, MMP-2, Col I, Col Ⅲ and α-SMA were increased, while that of eEF2K was decreased in model group (P<0.05). Compared with model group, the fibrosis score, expression levels of GSK3β, p-GSK3β, p-eEF2K (Ser70, Ser392, Ser470), pro-MMP-2, MMP-2, Col I, Col Ⅲ and α-SMA were decreased, but the expression level of eEF2K was increased in inhibition group (P<0.05). Conclusion: GSK3β can activate eEF2K by phosphorylation at the sites of Ser70, Ser392 and Ser470, increase the contents of fibrosis indicators, promote the formation of pulmonary fibrosis, and aggravate lung tissue lesions.


Subject(s)
Animals , Collagen , Collagen Type I , Elongation Factor 2 Kinase/metabolism , Eukaryota/metabolism , Fibrosis , Glycogen Synthase Kinase 3 beta , Male , Matrix Metalloproteinase 2/metabolism , Mice , Mice, Inbred C57BL , Pulmonary Fibrosis/chemically induced , Signal Transduction
6.
Acta Pharmaceutica Sinica B ; (6): 1274-1285, 2021.
Article in English | WPRIM | ID: wpr-881198

ABSTRACT

Liver is the most common metastatic site for colorectal cancer (CRC), there is no satisfied approach to treat CRC liver metastasis (CRCLM). Here, we investigated the role of a polycomb protein BMI-1 in CRCLM. Immunohistochemical analysis showed that BMI-1 expression in liver metastases was upregulated and associated with T4 stage, invasion depth and right-sided primary tumor. Knockdown

7.
Acta Pharmaceutica Sinica B ; (6): 599-608, 2021.
Article in English | WPRIM | ID: wpr-881158

ABSTRACT

Redox-altered plasticity refers to redox-dependent reversible changes in synaptic plasticity

8.
Acta Pharmaceutica Sinica B ; (6): 71-88, 2021.
Article in English | WPRIM | ID: wpr-881125

ABSTRACT

@#Disrupted redox status primarily contributes to myocardial ischemia/reperfusion injury (MIRI). NRF2, the endogenous antioxidant regulator, might provide therapeutic benefits. Dihydrotanshinone-I (DT) is an active component in Salvia miltiorrhiza with NRF2 induction potency. This study seeks to validate functional links between NRF2 and cardioprotection of DT and to investigate the molecular mechanism particularly emphasizing on NRF2 cytoplasmic/nuclear translocation. DT potently induced NRF2 nuclear accumulation, ameliorating post-reperfusion injuries via redox alterations. Abrogated cardioprotection in NRF2-deficient mice and cardiomyocytes strongly supports NRF2-dependent cardioprotection of DT. Mechanistically, DT phosphorylated NRF2 at Ser40, rendering its nuclear-import by dissociating from KEAP1 and inhibiting degradation. Importantly, we identified PKC-δ-(Thr505) phosphorylation as primary upstream event triggering NRF2-(Ser40) phosphorylation. Knockdown of PKC-δ dramatically retained NRF2 in cytoplasm, convincing its pivotal role in mediating NRF2 nuclear-import. NRF2 activity was further enhanced by activated PKB/GSK-3β signaling via nuclear-export signal blockage independent of PKC-δ activation. By demonstrating independent modulation of PKC-δ and PKB/GSK-3β/Fyn signaling, we highlight the ability of DT to exploit both nuclear import and export regulation of NRF2 in treating reperfusion injury harboring redox homeostasis alterations. Coactivation of PKC and PKB phenocopied cardioprotection of DT in vitro and in vivo, further supporting the potential applicability of this rationale. Graphical abstract

9.
Frontiers of Medicine ; (4): 221-231, 2021.
Article in English | WPRIM | ID: wpr-880964

ABSTRACT

The mammalian target of rapamycin (mTOR) critically regulates several essential biological functions, such as cell growth, metabolism, survival, and immune response by forming two important complexes, namely, mTOR complex 1 (mTORC1) and complex 2 (mTORC2). mTOR signaling is often dysregulated in cancers and has been considered an attractive cancer therapeutic target. Great efforts have been made to develop efficacious mTOR inhibitors, particularly mTOR kinase inhibitors, which suppress mTORC1 and mTORC2; however, major success has not been achieved. With the strong scientific rationale, the intriguing question is why cancers are insensitive or not responsive to mTOR-targeted cancer therapy in clinics. Beyond early findings on induced activation of PI3K/Akt, MEK/ERK, and Mnk/eIF4E survival signaling pathways that compromise the efficacy of rapalog-based cancer therapy, recent findings on the essential role of GSK3 in mediating cancer cell response to mTOR inhibitors and mTORC1 inhibition-induced upregulation of PD-L1 in cancer cells may provide some explanations. These new findings may also offer us the opportunity to rationally utilize mTOR inhibitors in cancer therapy. Further elucidation of the biology of complicated mTOR networks may bring us the hope to develop effective therapeutic strategies with mTOR inhibitors against cancer.


Subject(s)
Glycogen Synthase Kinase 3 , Mechanistic Target of Rapamycin Complex 2 , Neoplasms/drug therapy , Phosphatidylinositol 3-Kinases , Protein Kinase Inhibitors , Proto-Oncogene Proteins c-akt , TOR Serine-Threonine Kinases
10.
Acta Pharmaceutica Sinica B ; (6): 3433-3446, 2021.
Article in English | WPRIM | ID: wpr-922806

ABSTRACT

RAS, a member of the small GTPase family, functions as a binary switch by shifting between inactive GDP-loaded and active GTP-loaded state. RAS gain-of-function mutations are one of the leading causes in human oncogenesis, accounting for ∼19% of the global cancer burden. As a well-recognized target in malignancy, RAS has been intensively studied in the past decades. Despite the sustained efforts, many failures occurred in the earlier exploration and resulted in an 'undruggable' feature of RAS proteins. Phosphorylation at several residues has been recently determined as regulators for wild-type and mutated RAS proteins. Therefore, the development of RAS inhibitors directly targeting the RAS mutants or towards upstream regulatory kinases supplies a novel direction for tackling the anti-RAS difficulties. A better understanding of RAS phosphorylation can contribute to future therapeutic strategies. In this review, we comprehensively summarized the current advances in RAS phosphorylation and provided mechanistic insights into the signaling transduction of associated pathways. Importantly, the preclinical and clinical success in developing anti-RAS drugs targeting the upstream kinases and potential directions of harnessing allostery to target RAS phosphorylation sites were also discussed.

11.
Acta Pharmaceutica Sinica B ; (6): 3105-3119, 2021.
Article in English | WPRIM | ID: wpr-922783

ABSTRACT

Pulmonary fibrosis (PF) is a chronic, progressive, fatal interstitial lung disease with limited available therapeutic strategies. We recently reported that the protein kinase glycogen synthase kinase-3

12.
Acta Pharmaceutica Sinica B ; (6): 2983-2994, 2021.
Article in English | WPRIM | ID: wpr-922779

ABSTRACT

Genomic instability remains an enabling feature of cancer and promotes malignant transformation. Alterations of DNA damage response (DDR) pathways allow genomic instability, generate neoantigens, upregulate the expression of programmed death ligand 1 (PD-L1) and interact with signaling such as cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) signaling. Here, we review the basic knowledge of DDR pathways, mechanisms of genomic instability induced by DDR alterations, impacts of DDR alterations on immune system, and the potential applications of DDR alterations as biomarkers and therapeutic targets in cancer immunotherapy.

13.
Article in English | WPRIM | ID: wpr-888655

ABSTRACT

OBJECTIVE@#To investigate the protective effects of Shexiang Tongxin Dropping Pill (, STDP) following sodium laurate-induced coronary microembolization (CME) in rats.@*METHODS@#Forty rats were divided into 4 groups: the control (sham) group, CME group, low-dose STDP pretreatment group (20 mg·kg@*RESULTS@#The rats in the CME group showed a significant increase in the fibrinogen-like protein 2 expression level and mitochondrial dysfunction and a decrease in the expression level of antioxidant biomarkers (superoxide dismutase and catalase, P<0.01 for all). In contrast, the rats in the low- and high-dose STDP pretreatment groups showed a significant decrease in coronary microthrombi (P<0.05); moreover, STDP restored the antioxidant-related protein activities and mitochondrial function, inhibited mPTP opening, decreased AKT-Ser473 phosphorylation, and increased GSK3β-Ser9 phosphorylation (P<0.05 or P<0.01).@*CONCLUSION@#STDP may be useful for treatment of CME, possibly via regulation of mPTP opening and AKT/GSK3β phosphorylation.

14.
Article in Chinese | WPRIM | ID: wpr-883515

ABSTRACT

Parkinson's disease(PD)is the second most common neurodegenerative disease in the world;however,it lacks effective and safe treatments.Ginkgo biloba dropping pill(GBDP),a unique Chinese G.biloba leaf extract preparation,exhibits antioxidant and neuroprotective effects and has a potential as an alternative therapy for PD.Thus,the aims of this study were to evaluate the effects of GBDP in in vitro and in vivo PD models and to compare the chemical constituents and pharmacological activities of GBDP and the G.biloba extract EGb 761.Using liquid chromatography tandem-mass spectrometry,46 GBDP constitu-ents were identified.Principal component analysis identified differences in the chemical profiles of GBDP and EGb 761.A quantitative analysis of 12 constituents showed that GBDP had higher levels of several flavonoids and terpene trilactones than EGb 761,whereas EGb 761 had higher levels of organic acids.Moreover,we found that GBDP prevented 6-hydroxydopamine-induced dopaminergic neuron loss in zebrafish and improved cognitive impairment and neuronal damage in methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced PD mice.Although similar effects were observed after EGb 761 treatment,the neuroprotective effects were greater after GBDP treatment on several endpoints.In addition,in vitro results suggested that the Akt/GSK3β pathway may be involved in the neuroprotective effects of GBDP.These findings demonstrated that GBDP have potential neuroprotective effects in the treatment of PD.

15.
Article in Chinese | WPRIM | ID: wpr-909536

ABSTRACT

Objective:To explore the modulatory effects of GSK-3β/β-catenin signaling pathway on anxiety- and depression-like behavior of mice induced by chronic sleep deprivation (CSD).Methods:Forty-eight 10-week-old C57BL/6J male mice were selected and randomly divided into four groups(with 12 mice in each group): control group, inhibitor-only group (LiCl), chronic sleep deprivation group (CSD) and inhibitor with CSD group (LiCl+ CSD). Elevated plus maze (EPM) and forced swimming test (FST) were used to evaluate the behavior of mice, HE staining was used to observe the pathological morphological changes of hippocampal neurons, and Western blot was used to detect the protein expressions of β-catenin, GSK-3β and p-GSK-3β in hippocampal tissues. SPSS 22.0 software was used for independent sample t-test and one way ANOVA. Results:After modeling, the body weight of mice in the CSD group ((26.53±0.76)g) was significantly lower than that of the control group ((28.00±0.37)g) ( q=4.119, P=0.041), and the body weight in the LiCl+ CSD group ((28.04±0.86)g) was improved compared with CSD group ( q=4.240, P=0.036). In EPM, the ratio of the entering times and the proportion of the staying time in the open arm in the CSD group ((48.44±9.16)%) and ((16.47±10.42)%) were significantly lower than those in the control group ((68.92±11.71)% and (42.93±15.89)%) ( q=4.660, P=0.018, q=4.346, P=0.029), but the staying time in the open arm in the LiCl+ CSD group ((32.92±12.05)%) was significantly higher than that in the CSD group ( q=2.432, P=0.038). In FST, the percentage of floating immobility time of the mice in the CSD group ((55.00±5.36)%) was significantly longer than that of the control group ((39.95±2.87)%) ( P=0.023), which was decreased significantly in the LiCl+ CSD group ((42.00±7.92)%) than that in the CSD group ( P=0.040). Western blot results showed that, the expressions of p-GSK-3β and β-catenin in the hippocampus of CSD group were decreased significantly ( P=0.040, P=0.008), while the expression of GSK-3β was significantly increased than that of the control group ( P<0.001). Both p-GSK-3β and β-catenin were significantly reversed in CSD+ LiCl group than that in CSD ( P=0.034, P=0.038). Conclusion:The GSK-3β/β-catenin signaling pathway may be involved in the regulation of CSD-induced anxiety and depression-like behaviors in mice.

16.
Article in Chinese | WPRIM | ID: wpr-909534

ABSTRACT

Objective:To investigate the effect of GluA2-3Y which is an inhibitor of AMPA(α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid) receptor internalization on cognitive function and hippocampal postsynaptic protein expression in rats with chronic cerebral hypoperfusion.Methods:Forty-eight adult male SD rats were randomly divided into Sham group, 2VO group, high-dose GluA2-3Y group and low-dose GluA2-3Y group according to random number table, with 12 rats in each group.The chronic cerebral hypoperfusion model of rat was established by two vessel occlusion (2VO) while the Sham operation was performed in rats of Sham group.The rats in high dose GluA2-3Y group and low dose GluA2-3Y group were intraperitoneal injected with 3 μmol/kg and 0.03 μmol/kg GluA2-3Y respectively once a day for 2 weeks. Rats in 2VO group and Sham group were intraperitoneally injected with control peptide. Morris water maze test and new object recognition test were performed to evaluate the learning and memory ability of rats, and Western blot was used to evaluate the expression of Akt1、GSK3β、p-GSK3β、GluA2 and PSD-95 in rat hippocampus. The expressions of GluA2 and PSD-95 in rat hippocampus were evaluated by immunofluorescence. SPSS 23.0 software was used for data analysis. The comparison between multiple groups was analyzed by one-way ANOVA and repeated measurement ANOVA was used to analyze Morris water maze results. And independent-samples t-test was used for pairwise comparisons. Results:(1)In Morris water maze trials, the results of repeated measurement ANOVA showed that the interaction between group and time of escape latency of rats in each group was not significant ( F=0.79, P>0.05), and the group main effect and time main effect were significant ( F=24.44, 40.42, both P<0.05). On the 5th day of navigation trials, the escape latency of rats in 2VO group was longer than that in sham group ( t=5.87, P<0.05). The escape latency of rats in low dose GluA2-3Y group and high dose GluA2-3Y group were significantly shorter than that in 2VO group ( t=2.20, 3.41, both P<0.05), but there was no significant difference between low dose GluA2-3Y group and high dose GluA2-3Y group ( t=1.37, P>0.05). The target quadrant residence time and resolution coefficient ((14.57±1.40)s, (0.15±0.10)) in 2VO group were significantly lower than those in Sham group ((23.71±2.57)s, (0.40±0.06)) ( t=3.23, 2.24, both P<0.05), while the target quadrant residence time in high dose GluA2-3Y group ((20.19±1.53)s) and low dose GluA2-3Y group ((20.31±2.06)s) were longer than that in 2VO group( t=2.71, 2.35, both P<0.05). The discrimination coefficients in high dose GluA2-3Y group (0.47±0.10) and low dose GluA2-3Y group (0.59±0.06) were higher than that of 2VO group ( t=2.21, 3.94, both P<0.05). (2)The Western blot results showed that the expression of PSD-95 and GluA2 in hippocampus of rats in 2VO group were significantly lower than those in Sham group ( t=2.31, 2.20, both P<0.05), and the expression of PSD-95 in high dose GluA2-3Y group (1.026±0.056) was significantly higher than that in 2VO group ((0.760±0.061), t=2.49, P<0.05), while there was no significant difference between low-dose GluA2-3Y group and 2VO group( t=0.96, P>0.05). The expression of GluA2 in low-dose GluA2-3Y group was higher than that in 2VO Group ((1.130±0.087), (0.766±0.080), t=2.37, P<0.05), but there was no significant difference between high-dose GluA2-3Y group and 2VO group( t=1.06, P>0.05). (3) Immunofluorescence showed that compared with Sham group, the expression of PSD-95 and GluA2 in 2VO group decreased ( t=4.23, 2.57, P<0.05). Compared with 2VO group, the expression of PSD-95 and GluA2 in high dose GluA2-3Y group and low dose GluA2-3Y group increased significantly, and the differences were statistically significant (PSD-95: (7.757±0.578), (12.057±0.578), t=3.14, 6.96, both P<0.05; (9.721±0.950), (16.610±0.950), t=4.56, 9.34, both P<0.05). (4) The results of Western blot showed that the expression GSK3β in hippocampus of rats in each group were not statistically different( F=2.03, P>0.05). There were significant differences in the expression of Akt1, p-GSK3β and the percentage of p-GSK3β/GSK3β in hippocampus of rats in each group ( F=8.30, 4.76, 3.57, all P<0.05). Compared with Sham group, the levels of Akt1, p-GSK3β and the percentage of p-GSK3β/GSK3β in 2VO group were significantly lower ( t=3.00, 2.81, 3.17, all P<0.05). Compared with 2VO group, the levels of Akt1, p-GSK3β and p-GSK3β/GSK3β percentage in low dose GluA2-3Y group and high-dose GluA2-3Y group were significantly higher (Akt1: t=2.05, 5.20, both P<0.05; p-GSK3β: t=2.49, 4.15, both P<0.05; p-GSK3β/GSK3β percentage: t=2.30, 2.97, both P<0.05). Conclusion:GluA2-3Y, an AMPA receptor internalization inhibitor, can alleviate the cognitive impairment in rats with chronic cerebral hypoperfusion, which may be related to the increased expression of Akt1, p-GSK3β and postsynaptic proteins.

17.
Article in Chinese | WPRIM | ID: wpr-906511

ABSTRACT

Objective:To observe the effect of Zuoguiwan on bone metabolism and Wnt/<italic>β</italic>-catenin signaling pathway in ovariectomized osteoporotic rats model, and to explore the molecular biological mechanism of Zuoguiwan in the prevention and treatment of osteoporosis. Method:The rat model of postmenopausal osteoporosis was established by bilateral ovariectomy, 60 female SD rats were randomly divided into sham operation group, model group, positive group (estradiol valerate tablet 0.05 mg·kg<sup>-1</sup>·d<sup>-1</sup>) and low, middle and high dose groups of Zuoguiwan (5.5,11,22 g·kg<sup>-1</sup>·d<sup>-1</sup>).After successful establishment of the model in the 13<sup>th</sup> week, intragastric administration (<italic>ig</italic>) was given once a day for a total of 12 weeks. After administration, the histomorphological changes of femur in rats were observed by hematoxylin-eosin (HE) staining, the bone mineral density (BMD) and bone mineral content(BMC) of femur were measured by dual energy X-ray apparatus, and the biomechanical properties of bone were measured by MTS Acumen3 biomechanical testing system. The contents of bone alkaline phosphatase (BALP), bone glaprotein(BGP),estradiol (E<sub>2</sub>) ,and tartrate-resistant acid phosphatase (TRAP), type Ⅰ procollagen N-terminal propeptide (PINP) in serum were detected by enzyme-linked immunosorbent assay (ELISA). Western blot was used to detect the protein level of Wnt2,<italic>β</italic>-catenin,low density lipoprotein related receptor protein 5 (LRP5) and the phosphorylation level of glycogen synthase kinase-3<italic>β</italic>(GSK-3<italic>β</italic>) in rat tibia. Result:Compared with sham operation group, the maximum load and stiffness of BMD,BMC, in the model group decreased significantly(<italic>P</italic><0.01), the contents of E<sub>2</sub> and PINP in serum decreased significantly(<italic>P</italic><0.01), the content of BALP,BGP,TRAP increased significantly(<italic>P</italic><0.01), the expression levels of Wnt2,p-GSK-3<italic>β </italic>Ser9,LRP5 and <italic>β</italic>-catenin protein in bone tissue decreased significantly(<italic>P</italic><0.01), the trabecula of femur became thinner and thinner, the number of bone trabeculae decreased. Compared with model group, the maximum load and stiffness of BMD,BMC, in estradiol group and Zuoguiwan group were significantly increased (<italic>P</italic><0.05,<italic>P</italic><0.01), the contents of serum E<sub>2</sub> and PINP were significantly increased (<italic>P</italic><0.05,<italic>P</italic><0.01), the content of BALP,BGP,TRAP was significantly decreased (<italic>P</italic><0.01), and the expression level of Wnt2,p-GSK-3<italic>β</italic> Ser9,LRP5, <italic>β</italic>-catenin protein in bone tissue was significantly increased (<italic>P</italic><0.05,<italic>P</italic><0.01) , the trabeculae of femur became thicker, the number increased, the structure was basically clear. Conclusion:Zuoguiwan has a certain preventive and therapeutic effect on osteoporosis in ovariectomized rats, and its mechanism may be related to increasing the level of estrogen, activating Wnt/<italic>β</italic>-catenin signaling pathway, up-regulating the expression of Wnt2 and LRP5 protein, inhibiting the activity of GSK-3<italic>β</italic>, reducing the degradation of <italic>β</italic>-catenin, coordinating the dynamic coupling balance between bone formation and bone resorption, correcting the disorder of bone metabolism and improving bone morphology.

18.
Article in Chinese | WPRIM | ID: wpr-905988

ABSTRACT

Objective:To observe the effects of Huazhuo Jiedu Shugan Prescription (HZJDSG) on learning, memory, and the expression of phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase-3<italic>β</italic> (GSK-3<italic>β</italic>) pathway-related proteins in epileptic rats, and to explore its possible mechanism. Method:Forty-eight SPF male SD rats were randomly divided into a normal group, a model group, a sodium valproate (0.19 g·kg<sup>-1</sup>) group, and low- (2.7 g·kg<sup>-1</sup>), medium- (5.4 g·kg<sup>-1</sup>), and high-dose (10.8 g·kg<sup>-1</sup>) HZJDSG groups, with eight rats in each group. The normal group received 0.9% sodium chloride solution (0.035 g·kg<sup>-1</sup>) by intraperitoneal injection, and the other five groups received pentetrazol (PTZ) at the same dose to induce a chronic epilepsy model for a total of 14 times. The drug groups received corresponding drugs and the normal group and the model group received 0.9% sodium chloride solution at the same volume once a day for 28 days. During the drug intervention period, epilepsy was maintained in each modeling group by intraperitoneal injection of PTZ on day 7, 14, 21, and 28. The behavioral changes of rats were observed by Morris water maze and the pathomorphological changes of rat hippocampal neurons by hematoxylin-eosin (HE) staining. The protein expression of phosphorylation Akt(p-Akt)and p-GSK-3<italic>β</italic> was detected by immunohistochemistry and the protein expression of PI3K, Akt, p-Akt, GSK-3<italic>β</italic>, and p-GSK-3<italic>β</italic> by Western blot. Result:Compared with the normal group, the model group showed prolonged platform finding time (<italic>P</italic><0.01), reduced number of platform crossings (<italic>P</italic><0.01), structural damage of neurons in the CA1 region of the hippocampus, down-regulated protein expression of p-Akt and p-GSK-3<italic>β </italic>in the CA1 region of the hippocampus (<italic>P</italic><0.05), and reduced relative expression of PI3K, p-Akt, and p-GSK-3<italic>β</italic> in the hippocampus (<italic>P</italic><0.01). Compared with the model group, the sodium valproate group and the HZJDSG groups showed shortened platform finding time (<italic>P</italic><0.01) and improved neuronal structure in the CA1 region of the hippocampus, while the sodium valproate group and the high- and medium-dose HZJDSG groups exhibited increased number of platform crossings (<italic>P</italic><0.01), up-regulated protein expression of p-Akt and p-GSK-3<italic>β</italic> in the CA1 region of the hippocampus (<italic>P</italic><0.05), and elevated relative expression of PI3K, p-Akt, and p-GSK-3<italic>β</italic> (<italic>P</italic><0.01). Conclusion:HZJDSG can improve the learning and memory of epileptic rats, and its antiepileptic effect may be achieved by the activation of PI3K/Akt/GSK-3<italic>β</italic> pathway-related proteins.

19.
Article in Chinese | WPRIM | ID: wpr-905833

ABSTRACT

Objective:To observe the effect of tetrahydroxy stilbene glycoside (TSG) on the expression of glycogen synthase kinase 3<italic>β </italic>(GSK3<italic>β</italic>), cyclic adenosine monophosphate-dependent protein kinase (PKA) and Serine/threonine phosphatase 2A(PP2A) in the brain of amyloid precursor protein/presenilin-1/Tau (APP/PS1/Tau) triple-transgenic mice dementia model. Method:A total of forty-five 8-month-old APP/PS1/Tau transgenic mice were randomly divided into model group, positive control group (Huperzine-A, 0.15 mg·kg<sup>-1</sup>), low, medium and high dose TSG groups (TSG, 0.033,0.1,0.3 g·kg<sup>-1</sup>), with 9 mice in each group, and another nine C5B7L/6J mice of the same age were selected as normal control group. After 60 days of intragastric administration, the general structure of hippocampal neurons was observed by hematoxylin-eosin (HE) staining, immunohistochemical (IHC) was used to detect the expression of PKA protein in the brain of mice in each group, the mRNA expression levels of GSK3<italic>β</italic>, PKA and PP2A were detected by real time quantitative reverse transcription polymerase chain reaction (Real-time PCR), and protein expression levels of GSK3<italic>β</italic> and PP2A were detected by Western blot. Result:Compared with the normal control group, the apoptosis level of neurons in the model group was significantly increased, the protein and mRNA expression levels of GSK3<italic>β</italic> and PKA were significantly increased (<italic>P</italic><0.05, <italic>P</italic><0.01), and the protein and mRNA expression levels of PP2A were significantly decreased (<italic>P</italic><0.05, <italic>P</italic><0.01). Compared with the model group, the apoptosis level of neurons in each treatment group was significantly down-regulated, the protein and mRNA expression levels of GSK3<italic>β</italic> and PKA were significantly down-regulated (<italic>P</italic><0.05, <italic>P</italic><0.01), and the protein and mRNA expression levels of PP2A were significantly increased (<italic>P</italic><0.05, <italic>P</italic><0.01). Conclusion:The mechanism of TSG in the treatment of Alzheimer's disease (AD) may be related to lowering the transcription and expression of GSK3<italic>β</italic> and PKA, increasing the transcription and expression of PP2A.

20.
Article in Chinese | WPRIM | ID: wpr-905066

ABSTRACT

Objective:To investigate the effect of Huangjingwan (HW) on the activities of glycogen synthase kinase-3β (GSK-3β), protein phosphatase 2A (PP2A) and the mechanism in inhibiting tau protein hyperphosphorylation in the hippocampal neurons of mice with Alzheimer's disease. Method:After subcutaneous injection with 1.0% D-galactose (0.14 g·kg-1·d-1) into the back and neck of mice for 4 weeks, the right ventricle of mice was injected with 2 μL (75 ng) of okadaic acid for one time to make AD model, and the successfully modeled AD mice were selected by Morris water maze. Then, the selected AD mice were randomly divided into AD model group, memantine group (1.3×10-3 g·kg-1·d-1) and HW group (2.5 g·kg-1·d-1). In addition, the sham model control group and the normal control group were set up. At the same time, 2 μL normal saline was injected into the right ventricle of mouse in the sham model control group for modeling control. Two weeks after modeling, the mice in the two experimental drug groups were given the corresponding dose of the experimental drug by gavage for 4 weeks. In addition, after 2 weeks of AD modeling, mice in control group and AD model group were intragastrically administrated with the same amount of normal saline daily for 4 weeks. The mice in normal control group were only given daily feed. At the end of gavage, all the mice were tested by the open field experiment and jumping platform experiment to evaluate the differences in exploratory activity ability, anxiety level and learning and memory ability. The number of neurons in CA1 and CA3 areas of hippocampus in all the mice was detected by Nissl staining. Quantitative real-time polymerase chain reaction (Real-time PCR) was used to detect mRNA expressions of GSK-3β and PP2A in hippocampus of mice in each group. Protein expressions of GSK-3β, PP2A, phosphorylated tau (p-tau) and total tau protein (t-tau) in hippocampus of mice in each group were detected by Western blot. Result:Compared with the normal control group, mice in AD model group showed an obvious dementia state, which was characterized by a lower spontaneous activity, lower exploration behavior ability, higher anxiety level, less movement and easier to stay and hide, longer learning response time, significantly increased number of learning and memory errors, and decreased numbers of hippocampal neuron in CA1 and CA3 areas, and reduced mRNA and protein expressions of PP2A, mRNA and protein expressions of GSK-3β, p-tau protein and the ratio of p-tau/t-tau were all increased significantly (P<0.01), while expression of t-tau protein was decreased, with no significant difference. Compared with the AD model group, mice in the HW group showed a higher spontaneous activity, higher exploration ability, lower anxiety level, higher learning and memory performance, and the numbers of hippocampal neuron in CA1 and CA3 areas increased, while mRNA and protein expressions of PP2A increased, and the mRNA and protein expressions of GSK-3β, the expression of p-tau protein and the ratio of p-tau/t-tau were all decreased significantly (P<0.01), but with no significant difference in the protein expression of t-tau. Conclusion:HW can inhibit tau hyperphosphorylation in hippocampal neurons of AD mice, restore tau protein function, protect hippocampal neurons, and exert an anti-AD effect, which may be related to the regulatory mechanism in the activity balance between GSK-3β and PP2A in hippocampal neurons.

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