Glycogen serves as the principal energy reserve for metabolic processes in aquatic shellfish and substantially contributes to the flavor and quality of oysters.The Jinjiang oyster(Crassostrea ariakensis)is an economic...Glycogen serves as the principal energy reserve for metabolic processes in aquatic shellfish and substantially contributes to the flavor and quality of oysters.The Jinjiang oyster(Crassostrea ariakensis)is an economically and ecologically important species in China.In the present study,RNA sequencing(RNA-seq)and assay for transposase-accessible chromatin using sequencing(ATAC-seq)were performed to investigate gene expression and chromatin accessibility variations in oysters with different glycogen contents.Analysis identified 9483 differentially expressed genes(DEGs)and 7215 genes with significantly differential chromatin accessibility(DCAGs)were obtained,with an overlap of 2600 genes between them.Notably,a significant proportion of these genes were enriched in pathways related to glycogen metabolism,including“Glycogen metabolic process”and“Starch and sucrose metabolism”.In addition,genome-wide association study(GWAS)identified 526 single nucleotide polymorphism(SNP)loci associated with glycogen content.These loci corresponded to 241 genes,63 of which were categorized as both DEGs and DCAGs.This study enriches basic research data and provides insights into the molecular mechanisms underlying the regulation of glycogen metabolism in C.ariakensis.展开更多
Background:This study aimed to determine the effect of different carbohydrate(CHO)doses on exercise capacity in patients with McArdle disease—the paradigm of“exercise intolerance”,characterized by complete muscle g...Background:This study aimed to determine the effect of different carbohydrate(CHO)doses on exercise capacity in patients with McArdle disease—the paradigm of“exercise intolerance”,characterized by complete muscle glycogen unavailability—and to determine whether higher exogenous glucose levels affect metabolic responses at the McArdle muscle cell(in vitro)level.Methods:Patients with McArdle disease(n=8)and healthy controls(n=9)underwent a 12-min submaximal cycling constant-load bout followed by a maximal ramp test 15 min after ingesting a non-caloric placebo.In a randomized,double-blinded,cross-over design,patients repeated the tests after consuming either 75 g or 150 g of CHO(glucose:fructose=2:1).Cardiorespiratory,biochemical,perceptual,and electromyographic(EMG)variables were assessed.Additionally,glucose uptake and lactate appearance were studied in vitro in wild-type and McArdle mouse myotubes cultured with increasing glucose concentrations(0.35,1.00,4.50,and 10.00 g/L).Results:Compared with controls,patients showed the“classical”second-wind phenomenon(after prior disproportionate tachycardia,myalgia,and excess electromyographic activity during submaximal exercise,all p<0.05)and an impaired endurance exercise capacity(-51%ventilatory threshold and55%peak power output,both p<0.001).Regardless of the CHO dose(p<0.05 for both doses compared with the placebo),CHO intake increased blood glucose and lactate levels,decreased fat oxidation rates,and attenuated the second wind in the patients.However,only the higher dose increased ventilatory threshold(+27%,p=0.010)and peak power output(+18%,p=0.007).In vitro analyses revealed no differences in lactate levels across glucose concentrations in wild-type myotubes,whereas a doseresponse effect was observed in McArdle myotubes.Conclusion:CHO intake exerts beneficial effects on exercise capacity in McArdle disease,a condition associated with total muscle glycogen unavailability.Some of these benefits are dose dependent.展开更多
Glycogen metabolism plays a key role in the development of hepatoellular carcinoma(HCC),but the function of glycogen metabolism genes in the tumor microenvironment(TME)is still to be elucidated.Single cell RNA-seq dat...Glycogen metabolism plays a key role in the development of hepatoellular carcinoma(HCC),but the function of glycogen metabolism genes in the tumor microenvironment(TME)is still to be elucidated.Single cell RNA-seq data were obtained from ten HCC tumor samples totaling 64,545 cells and 65 glycogen metabolism genes were analyzed bya nonnegative matrix factorization(NMF).The prognosis and immune response of new glycogen TME cell dusters were predicted by using HCC and immunotherapy cohorts from public databases.HOC single cell analysis was divided into fibroblasts,NT T cells,macrophages,endothelial clls,and B cells,which were separately divided into new cell clusters by glycogen metabolism gene annotation.Pseudo temporal trajectory analysis demonstrated the temporal differentiation trajectory of different glycogen subtype cell dusters.Cellular communication analysis revealed extensive interactions between endothelial cells with glycogen metabolizing TME cell.related subtypes and diferent glycogen subtype cell clusters.SCENIC analysis of transcription factors upstream of TME cell clusters with different glycogen metabolism.In addition,TME cell dusters of glycogen metabolism were found to be enriched in expression in CAF subtypes,CD8 depleted,M1,and M2 types.Bulk seq analysis showed the prognostic signifcance of glycogen metabolism.mediated TME cell dusters in HCC,while a significant immune response was found in the immunotherapy cohort in patients treated with immune checkpoint blockade(ICB),especially for CAFs,T cells,and macrophages In summary,our study reveals for the first time that glycogen metabolism mediates intercellular communication in the hepatocellular carcinoma microenvironment while elucidating the anti-tumor mechanisms and immune prognostic responses of different subtypes of cell dusters.展开更多
The agp gene encoding the ADP-glucose pyrophosphorylase involved in cyanobacterial glycogen synthesis was amplified by PCR. The resulting agp fragment was cloned in plasmid pUC118 to generate plasmid pUCA. Part of the...The agp gene encoding the ADP-glucose pyrophosphorylase involved in cyanobacterial glycogen synthesis was amplified by PCR. The resulting agp fragment was cloned in plasmid pUC118 to generate plasmid pUCA. Part of the fragment within the agp DNA was deleted and replaced by an erythromycin resistance cassette to generate plasmid pUCAE, which was used to transform the Synechocystis sp. PCC 6803 wild-type strain and a mutant with resistance to erythromycin was obtained. PCR analysis of the genomic DNA from the resulting mutant indicated that the appropriate deletion and insertion indeed had occurred. The cell growth and Chl a, glycogen content in the mutant showed difference from those in the wild-type strain. The obtained biomass as well as the Chl a content in the mutant strain was higher than that of the wild-type strain, which suggested that the photosynthesis efficiency in the agp(-) strain was higher than that in the wild-type strain. No glycogen was found in the mutant, providing evidence for the correction of the mutant in physiological level.展开更多
The changes and correlations of muscle pH, glycogen, lactic acid and in- tramuscular fat oxidation in Duroc pigs 10 d after their slaughter, and the effects of different storage temperature and time on Duroc muscle pH...The changes and correlations of muscle pH, glycogen, lactic acid and in- tramuscular fat oxidation in Duroc pigs 10 d after their slaughter, and the effects of different storage temperature and time on Duroc muscle pH value, water loss rate, glycogen, lactic acid and 2-thiobarbituric acid (TBA) were studied. The results showed that during the 10 h after the slaughter, the pH value was decreased rapid- ly, the lactic acid content was increased significantly, while the glycogen and TBA contents were remained stable. At the storage temperature of 4 ℃, storage time showed no significant effects on Duroc muscle pH value and glycogen, lactic acid and TBA contents. At the storage temperature of -20 ℃, storage temperature had significant effects on pH value, while no significant effects on other indicators. The correlation analysis demonstrated that during the 10 h after the slaughter, the TBA content was negatively related to glycogen content (P〈0.05), but positively related to lactic content (P〈0.05); the pH value was negatively related to lactic acid content (P〈0.05). At the storage temperature of 4 ℃, the TBA content was negatively relat- ed to water loss rate (P〈0.01) and lactic acid content (P〈0.05); the water loss rate was positively related to pH value (P〈0.01) and lactic acid content (P〈0.05). At the storage temperature of -20 ℃, the TBA content was negatively related to pH value (P〈0.01) and positively related to water loss rate (P〈0.05); the water loss rate was negatively related to pH value (P〈0.01) and lactic acid content (P〈0.05).展开更多
Wnts are a large family of growth factors that mediate essential biological processes like embryogenesis, morpho- genesis and organogenesis. These proteins also play a role in oncogenesis, and they regulate apoptosis ...Wnts are a large family of growth factors that mediate essential biological processes like embryogenesis, morpho- genesis and organogenesis. These proteins also play a role in oncogenesis, and they regulate apoptosis in many tissues. Wnts bind to a membrane receptor complex comprised of a frizzled (FZD) G-protein-coupled receptor and a low-density lipoprotein (LDL) receptor-related protein (LRP). The formation of this ligand-receptor complex initiates a number of signaling cascades that include the canonical/beta-catenin pathway as well as several noncanonical pathways. In recent years, canonical Wnt signaling has been reported to play a significant role in the control of bone formation. Clinical studies have found that mutations in LRP-5 are associated with reduced bone mineral density (BMD) and fractures. Investigations of knockout and transgenic mouse models of Wnt pathway components have shown that canonical Wnt signaling modulates most aspects ofosteoblast physiology including proliferation, differentiation, function and apoptosis. Transgenic mice expressing a gain of function mutant of LRP-5 in bone, or mice lacking the Wnt antagonist secreted frizzled-related protein-l, exhibit elevated BMD and suppressed osteoblast apoptosis. In addition, preclinical studies with pharmacologic compounds such as those that inhibit glycogen synthase kinase-3β support the importance of the canonical Wnt pathway in modulation of bone formation and osteoblast apoptosis.展开更多
In this study, molecular interactions of the ligands, quercetin, gallic acid, and metformin with various diabetes mellitus-related protein targets, such as glycogen phosphorylase and peroxisome proliferatoractivated r...In this study, molecular interactions of the ligands, quercetin, gallic acid, and metformin with various diabetes mellitus-related protein targets, such as glycogen phosphorylase and peroxisome proliferatoractivated receptor gamma, were assessed. It was revealed that quercetin possesses good binding affinity to both targets. Quercetin is a major constituent of methanolic extracts of Phyllanthus emblica fruit. The antihyperglycemic effect of quercetin in streptozotocin(STZ)-induced diabetic rats was examined. The isolated quercetin administered at a dose of 75 mg/kg body weight produced a maximum decrease of14.78% in blood glucose levels in the diabetic rats after 7 days of treatment. Furthermore, quercetin doses of 50 and 75 mg/kg were shown to significantly improve the profiles of triglycerides, high-density lipoprotein, very-low-density lipoprotein, low-density lipoprotein, and total cholesterol at the end of the study in STZ-induced diabetic rats. The administration of quercetin(25, 50, and 75 mg/kg body weight)daily for 28 days in STZ-induced diabetic rats resulted in a significant decrease in blood glucose and urine sugar levels, with a considerable rise in plasma insulin and hemoglobin levels. Therefore, quercetin is a potential drug with antidiabetic and antihyperglycemic action mediated by changes in the levels of glucose, cholesterol, and triglycerides as indicated by in silico and in vivo studies.展开更多
Glycogen storage diseases (GSD) are inherited metabolic disorders of glycogen metabolism. Different hormones, including insulin, glucagon, and cortisol regulate the relationship of glycolysis, gluconeogenesis and gl...Glycogen storage diseases (GSD) are inherited metabolic disorders of glycogen metabolism. Different hormones, including insulin, glucagon, and cortisol regulate the relationship of glycolysis, gluconeogenesis and glycogen synthesis. The overall GSD incidence is estimated 1 case per 20000-43000 live births. There are over 12 types and they are classified based on the enzyme deficiency and the affected tissue. Disorders of glycogen degradation may affect primarily the liver, the muscle, or both. Type I a involves the liver, kidney and intestine (and I b also leukocytes), and the clinical manifestations are hepatomegaly, failure to thrive, hypoglycemia, hyperlactatemia, hyperuricemia and hyperlipidemia. Type Ilia involves both the liver and muscle, and lib solely the liver. The liver symptoms generally improve with age. Type IV usually presents in the first year of life, with hepatomegaly and growth retardation. The disease in general is progressive to cirrhosis. Type Ⅵ and Ⅳ are a heterogeneous group of diseases caused by a deficiency of the liver phosphorylase and phosphorylase kinase system. There is no hyperuricemia or hyperlactatemia. Type Ⅺ is characterized by hepatic glycogenosis and renal Fanconi syndrome. Type Ⅱ is a prototype of inborn lysosomal storage diseases and involves many organs but primarily the muscle. Types V and Ⅶ involve only the muscle.展开更多
Polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) protocol was employed for revealing microbial community structure and succession in a sequential anaerobic and aerobic reactor perform...Polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) protocol was employed for revealing microbial community structure and succession in a sequential anaerobic and aerobic reactor performing enhanced biological phosphorus removal (EBPR) during start-up period. High phosphorus removal was achieved after 15 d. On day 30, phosphorus removal efficiency reached to 83.2% and the start-up was finished. DGGE profiles of periodical sludge samples showed that dominant microbial species were 19 OTUs (operational taxonomy units). Unweighted pair-group method using arithmetic averages (UPGMA) clustering analysis revealed that rapid community succession correlated to low phosphorus removal rate and high phosphorus removal efficiency reflected on steady community structure. Sequencing results indicated that determined sequences (12 OTUs) belonged to Proteobacterium, Actinobacteria, Gemmatimonadales and unaffiliate group. Proteobacterium, Tetrasphaera elongate and Gemmatimonas aurantiaca may act important roles in phosphorus removal. With little amount as known glycogen accumulating organisms, Candidatus Competibacter phosphatis still at accumulating-phase had limited effect on microbial community structure. When climax community was obtained, dominant microbes were 14 OTUs. Microbes in a large amount were uncultured bacterium Thauera sp., uncultured y-Proteobacterium and Tetrasphaera elongata.展开更多
Diabetes mellitus affects virtually every organ system in the body and the degree of organ involvement depends on the duration and severity of the disease,and other co-morbidities.Gastrointestinal(GI) involvement can ...Diabetes mellitus affects virtually every organ system in the body and the degree of organ involvement depends on the duration and severity of the disease,and other co-morbidities.Gastrointestinal(GI) involvement can present with esophageal dysmotility,gastro-esophageal reflux disease(GERD),gastroparesis,enteropathy,non alcoholic fatty liver disease(NAFLD) and glycogenic hepatopathy.Severity of GERD is inversely related to glycemic control and management is with prokinetics and proton pump inhibitors.Diabetic gastroparesis manifests as early satiety,bloating,vomiting,abdominal pain and erratic glycemic control.Gastric emptying scintigraphy is considered the gold standard test for diagnosis.Management includes dietary modifications,maintaining euglycemia,prokinetics,endoscopic and surgical treatments.Diabetic enteropathy is also common and management involves glycemic control and symptomatic measures.NAFLD is considered a hepatic manifestation of metabolic syndrome and treatment ismainly lifestyle measures,with diabetes and dyslipidemia management when coexistent.Glycogenic hepatopathy is a manifestation of poorly controlled type 1 diabetes and is managed by prompt insulin treatment.Though GI complications of diabetes are relatively common,awareness about its manifestations and treatment options are low among physicians.Optimal management of GI complications is important for appropriate metabolic control of diabetes and improvement in quality of life of the patient.This review is an update on the GI complications of diabetes,their pathophysiology,diagnostic evaluation and management.展开更多
Objective:To analyze the expression of phosphatidylinositol 3 kinase(PI3-K),protein kinase B(PKB)and glycogen synthase kinase 3 beta(GSK-3β)in skeletal muscle tissue of gestational diabetes mellitus(GDM).Methods:A to...Objective:To analyze the expression of phosphatidylinositol 3 kinase(PI3-K),protein kinase B(PKB)and glycogen synthase kinase 3 beta(GSK-3β)in skeletal muscle tissue of gestational diabetes mellitus(GDM).Methods:A total of 90 cases of pregnant women were divided into observation group and control group according to the occurrence of GDM with 45 cases in either,and the expression of PI3-K,PKB,GSK-3βmRNA expression in skeletal muscle tissue was compared between two groups.Results:The total PI3-K p85 protein was significantly higher in the observation group compared with the control group,the activity of PI3-K was lower than that of the latter;The total PKB,GSK-3βprotein in skeletal tissue had no significant difference between two groups,while the serine phosphorylation levels of PKB and GSK-3βwere significantly lower in observation group compared with the control group.Conclusions:The downregulation of PI3-K,PKB and GSK-3βin skeletal tissue of GDM caused by phosphorylation dysfunction of signaling molecules is the reason for insulin resistance and transporter function decline which lead to GDM.展开更多
Although glycogen synthase kinase-3 (GSK-3) might act as a tumor suppressor since its inhibition is expected to mimic the activation of Wnt-signaling pathway, GSK-3β may contribute to NF-κB activation in cancer ce...Although glycogen synthase kinase-3 (GSK-3) might act as a tumor suppressor since its inhibition is expected to mimic the activation of Wnt-signaling pathway, GSK-3β may contribute to NF-κB activation in cancer cells leading to increased cancer cell proliferation and survival. Here we report that GSK-3β activity was involved in the proliferation of human ovarian cancer cell both in vitro and in vivo. Inhibition of GSK-3 activity by pharmacological inhibitors suppressed proliferation of the ovarian cancer cells. Overexpressing constitutively active form of GSK-3β induced entry into the S phase, increased cyclin D1 expression and facilitated the proliferation of ovarian cancer cells. Furthermore, GSK-3 inhibition prevented the formation of the tumor in nude mice generated by the inoculation of human ovarian cancer cells. Our findings thus suggest that GSK-3β activity is important for the proliferation of ovarian cancer cells, implicating this kinase as a potential therapeutic target in ovarian cancer.展开更多
AIM: To investigate the regulatory mechanism of glycogen synthase kinase 3β(GSK3β) in epithelialmesenchymal transition(EMT) process after proliferative vitreoretinopathy(PVR) induction. METHODS: Experimenta...AIM: To investigate the regulatory mechanism of glycogen synthase kinase 3β(GSK3β) in epithelialmesenchymal transition(EMT) process after proliferative vitreoretinopathy(PVR) induction. METHODS: Experimental PVR was induced by intravitreal injection of retinal pigment epithelium(RPE) cells in the eyes of rabbits. A PI3 K/Akt inhibitor(wortmannin) and a GSK3β inhibitor(Li Cl) were also injected at different time during PVR progress. Electroretinogram(ERG), ocular fundus photographs, and B-scan ultrasonography were used to observe the PVR progress. Western blot test on the extracted retina were performed at 1, 2, 4 wk. The expression of the mesenchymal marker vimentin was determined by immunohistochemistry. Toxicity of wortmannin and Li Cl were evaluated by ERG and Td Tmediated d UTP nick-end labeling(TUNEL) assay. The vitreous was also collected for metabolomic analysis. RESULTS: Experimental PVR could significantly lead to EMT, along with the suppressed expression of GSK3β and the activation of Wnt/β-catenin and PI3 K/Akt pathways. It was verified that upregulating the expression of GSK3β could effectively inhibit EMT process by suppressing Wnt/β-catenin and PI3 K/Akt pathways. CONCLUSION: GSK3β effectively inhibits EMT via the Wnt/β-catenin and PI3 K/Akt pathways. GSK3β may be regarded as a promising target of experimental PVR inhibition.展开更多
As a major microtubule-associated protein, tau plays an important role in promoting microtubule assembly and stabilizing microtubules. In Alzheimer’s disease(AD) and other tauopathies, the abnormally hyperphosphoryla...As a major microtubule-associated protein, tau plays an important role in promoting microtubule assembly and stabilizing microtubules. In Alzheimer’s disease(AD) and other tauopathies, the abnormally hyperphosphorylated tau proteins are aggregated into paired helical filaments and accumulated in the neurons with the form of neurofibrillary tangles. An imbalanced regulation in protein kinases and protein phosphatases is the direct cause of tau hyperphosphorylation. Among various kinases and phosphatases, glycogen synthase kinase-3β(GSK-3β) and protein phosphatase 2A(PP2A) are the most implicated. Accumulation of the hyperphosphorylated tau induces synaptic toxicity and cognitive impairments. Here, we review the upstream factors or pathways that can regulate GSK-3β or PP2A activity mainly based on our recent findings. We will also discuss the mechanisms that may underlie tau-induced synaptic toxicity.展开更多
Isoflurane and sevoflurane are both inhalation anesthetics,but in clinical application,sevoflurane has been considered to be less suitable for long-term anesthesia because of its catabolic compounds and potential neph...Isoflurane and sevoflurane are both inhalation anesthetics,but in clinical application,sevoflurane has been considered to be less suitable for long-term anesthesia because of its catabolic compounds and potential nephrotoxicity.Nevertheless,recent studies have shown that these two inhalation anesthetics are similar in hepatorenal toxicity,cost,and long-term anesthetic effect.Moreover,sevoflurane possibly has less cognitive impact on young mice.In this study,C57BL/6 mice aged 8–10 weeks were exposed to 1.2%isoflurane or 2.4%sevoflurane for 6 hours.Cognitive function and memory were examined in young mice using the novel object recognition,contextual fear conditioning,and cued-fear extinction tests.Western blot assay was performed to detect expression levels of D1 dopamine receptor,catechol-O-methyltransferase,phospho-glycogen synthase kinase-3β,and total glycogen synthase kinase-3βin the hippocampus.Our results show that impaired performance was not detected in mice exposed to sevoflurane during the novel object recognition test.Contextual memory impairment in the fear conditioning test was shorter in the sevoflurane group than the isoflurane group.Long-term sevoflurane exposure did not affect memory consolidation,while isoflurane led to memory consolidation and reduced retention.Downregulation of hippocampal D1 dopamine receptors and phosphorylated glycogen synthase kinase-3β/total glycogen synthase kinase-3βand upregulation of catechol-O-methyltransferase may be associated with differing memory performance after exposure to isoflurane or sevoflurane.These results confirm that sevoflurane has less effect on cognitive impairment than isoflurane,which may be related to expression of D1 dopamine receptors and catechol-O-methyltransferase and phosphorylation of glycogen synthase kinase-3βin the hippocampus.This study was approved by the Institutional Animal Care and Use Committee,Nanjing University,China on November 20,2017(approval No.20171102).展开更多
Acupuncture has been shown to ameliorate cognitive impairment of Alzheimer’s disease.Acupoints and stimulation frequency influence the therapeutic effect of electroacupuncture.Rat models of Alzheimer’s disease were ...Acupuncture has been shown to ameliorate cognitive impairment of Alzheimer’s disease.Acupoints and stimulation frequency influence the therapeutic effect of electroacupuncture.Rat models of Alzheimer’s disease were established by injecting amyloid beta 1–42(Aβ_(1–42))into the bilateral lateral ventricles.Electroacupuncture at 2,30,and 50 Hz was carried out at Baihui(GV20;15°obliquely to a depth of 2mm)and Shenshu(BL23;perpendicularly to 4–6 mm depth),once a day for 20 minutes(each),for 15 days,taking a break every 7 days.The Morris water maze test was conducted to assess the learning and memory.The expression levels of glycogen synthase kinase-3β(GSK-3β),p Ser9-GSK-3β,p Tyr216-GSK-3β,amyloid precursor protein and Aβ_(1–40) in the hippocampus were determined by western blot assay.Results demonstrated that electroacupuncture treatment at different frequencies markedly improved learning and memory ability,increased synaptic curvatures,decreased the width of synaptic clefts,thickened postsynaptic densities,and downregulated the expression of GSK-3β,amyloid precursor protein,and Aβ_(1–40).pSer9-GSK-3βexpression markedly decreased,while p Tyr216-GSK-3βexpression increased.High-frequency(50 Hz)electroacupuncture was more effective than low(2 Hz)or medium-frequency(30 Hz)electroacupuncture.In conclusion,electroacupuncture treatment exerts a protective effect against Aβ_(1–42)-induced learning and memory deficits and synapse-ultrastructure impairment via inhibition of GSK-3βactivity.Moreover,high-frequency electroacupuncture was the most effective therapy.展开更多
基金supported by the National Key R&D Program of China(2022YFD2400105,2018YFD0900104)Central Publicinterest Scientific Institution Basal Research Fund,CAFS(2021XT0102,2023TD30)+2 种基金Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(2021QNLM050103)Key Research and Development Project of Shandong Province(2021LZGC028)National Marine Genetic Resource Center。
文摘Glycogen serves as the principal energy reserve for metabolic processes in aquatic shellfish and substantially contributes to the flavor and quality of oysters.The Jinjiang oyster(Crassostrea ariakensis)is an economically and ecologically important species in China.In the present study,RNA sequencing(RNA-seq)and assay for transposase-accessible chromatin using sequencing(ATAC-seq)were performed to investigate gene expression and chromatin accessibility variations in oysters with different glycogen contents.Analysis identified 9483 differentially expressed genes(DEGs)and 7215 genes with significantly differential chromatin accessibility(DCAGs)were obtained,with an overlap of 2600 genes between them.Notably,a significant proportion of these genes were enriched in pathways related to glycogen metabolism,including“Glycogen metabolic process”and“Starch and sucrose metabolism”.In addition,genome-wide association study(GWAS)identified 526 single nucleotide polymorphism(SNP)loci associated with glycogen content.These loci corresponded to 241 genes,63 of which were categorized as both DEGs and DCAGs.This study enriches basic research data and provides insights into the molecular mechanisms underlying the regulation of glycogen metabolism in C.ariakensis.
基金supported by a Sara Borrell postdoctoral contract granted by Instituto de Salud Carlos III(CD21/00138).PLV,DB-G and AL are funded by the Spanish Ministry of Economy and Competitiveness and Fondos Feder(Alejandro Lucia,Grant No.PI18/00139)TP is funded by the Spanish Ministry of Economy and Competitiveness and Fondos Feder(Tomas Pinos,Grant No.PI22/00201).
文摘Background:This study aimed to determine the effect of different carbohydrate(CHO)doses on exercise capacity in patients with McArdle disease—the paradigm of“exercise intolerance”,characterized by complete muscle glycogen unavailability—and to determine whether higher exogenous glucose levels affect metabolic responses at the McArdle muscle cell(in vitro)level.Methods:Patients with McArdle disease(n=8)and healthy controls(n=9)underwent a 12-min submaximal cycling constant-load bout followed by a maximal ramp test 15 min after ingesting a non-caloric placebo.In a randomized,double-blinded,cross-over design,patients repeated the tests after consuming either 75 g or 150 g of CHO(glucose:fructose=2:1).Cardiorespiratory,biochemical,perceptual,and electromyographic(EMG)variables were assessed.Additionally,glucose uptake and lactate appearance were studied in vitro in wild-type and McArdle mouse myotubes cultured with increasing glucose concentrations(0.35,1.00,4.50,and 10.00 g/L).Results:Compared with controls,patients showed the“classical”second-wind phenomenon(after prior disproportionate tachycardia,myalgia,and excess electromyographic activity during submaximal exercise,all p<0.05)and an impaired endurance exercise capacity(-51%ventilatory threshold and55%peak power output,both p<0.001).Regardless of the CHO dose(p<0.05 for both doses compared with the placebo),CHO intake increased blood glucose and lactate levels,decreased fat oxidation rates,and attenuated the second wind in the patients.However,only the higher dose increased ventilatory threshold(+27%,p=0.010)and peak power output(+18%,p=0.007).In vitro analyses revealed no differences in lactate levels across glucose concentrations in wild-type myotubes,whereas a doseresponse effect was observed in McArdle myotubes.Conclusion:CHO intake exerts beneficial effects on exercise capacity in McArdle disease,a condition associated with total muscle glycogen unavailability.Some of these benefits are dose dependent.
基金Liuzhou City's Top Ten Hundred Talents Project,Liuzhou Science and Technology Project(Grant Nos.2021CBC0126 and 2021CBC0123)Guangxi Zhuang Autonomous Region Health and Family Planning Commission Projects(Z20210561,Z20210903)+1 种基金liuzhou Scienceand Technology Plan Projects(2021CBC0121,2021CBC0128).
文摘Glycogen metabolism plays a key role in the development of hepatoellular carcinoma(HCC),but the function of glycogen metabolism genes in the tumor microenvironment(TME)is still to be elucidated.Single cell RNA-seq data were obtained from ten HCC tumor samples totaling 64,545 cells and 65 glycogen metabolism genes were analyzed bya nonnegative matrix factorization(NMF).The prognosis and immune response of new glycogen TME cell dusters were predicted by using HCC and immunotherapy cohorts from public databases.HOC single cell analysis was divided into fibroblasts,NT T cells,macrophages,endothelial clls,and B cells,which were separately divided into new cell clusters by glycogen metabolism gene annotation.Pseudo temporal trajectory analysis demonstrated the temporal differentiation trajectory of different glycogen subtype cell dusters.Cellular communication analysis revealed extensive interactions between endothelial cells with glycogen metabolizing TME cell.related subtypes and diferent glycogen subtype cell clusters.SCENIC analysis of transcription factors upstream of TME cell clusters with different glycogen metabolism.In addition,TME cell dusters of glycogen metabolism were found to be enriched in expression in CAF subtypes,CD8 depleted,M1,and M2 types.Bulk seq analysis showed the prognostic signifcance of glycogen metabolism.mediated TME cell dusters in HCC,while a significant immune response was found in the immunotherapy cohort in patients treated with immune checkpoint blockade(ICB),especially for CAFs,T cells,and macrophages In summary,our study reveals for the first time that glycogen metabolism mediates intercellular communication in the hepatocellular carcinoma microenvironment while elucidating the anti-tumor mechanisms and immune prognostic responses of different subtypes of cell dusters.
文摘The agp gene encoding the ADP-glucose pyrophosphorylase involved in cyanobacterial glycogen synthesis was amplified by PCR. The resulting agp fragment was cloned in plasmid pUC118 to generate plasmid pUCA. Part of the fragment within the agp DNA was deleted and replaced by an erythromycin resistance cassette to generate plasmid pUCAE, which was used to transform the Synechocystis sp. PCC 6803 wild-type strain and a mutant with resistance to erythromycin was obtained. PCR analysis of the genomic DNA from the resulting mutant indicated that the appropriate deletion and insertion indeed had occurred. The cell growth and Chl a, glycogen content in the mutant showed difference from those in the wild-type strain. The obtained biomass as well as the Chl a content in the mutant strain was higher than that of the wild-type strain, which suggested that the photosynthesis efficiency in the agp(-) strain was higher than that in the wild-type strain. No glycogen was found in the mutant, providing evidence for the correction of the mutant in physiological level.
基金Supported by Funds for Swine Innovation Team Construction of Shandong Provincial Modern Agriculture Industry Technology System(SDAIT-06-011-03)Fine Breeds Engineering Project of Shandong Province(2011LZ013-01)China Swine Industry Technology System(CARS-36)~~
文摘The changes and correlations of muscle pH, glycogen, lactic acid and in- tramuscular fat oxidation in Duroc pigs 10 d after their slaughter, and the effects of different storage temperature and time on Duroc muscle pH value, water loss rate, glycogen, lactic acid and 2-thiobarbituric acid (TBA) were studied. The results showed that during the 10 h after the slaughter, the pH value was decreased rapid- ly, the lactic acid content was increased significantly, while the glycogen and TBA contents were remained stable. At the storage temperature of 4 ℃, storage time showed no significant effects on Duroc muscle pH value and glycogen, lactic acid and TBA contents. At the storage temperature of -20 ℃, storage temperature had significant effects on pH value, while no significant effects on other indicators. The correlation analysis demonstrated that during the 10 h after the slaughter, the TBA content was negatively related to glycogen content (P〈0.05), but positively related to lactic content (P〈0.05); the pH value was negatively related to lactic acid content (P〈0.05). At the storage temperature of 4 ℃, the TBA content was negatively relat- ed to water loss rate (P〈0.01) and lactic acid content (P〈0.05); the water loss rate was positively related to pH value (P〈0.01) and lactic acid content (P〈0.05). At the storage temperature of -20 ℃, the TBA content was negatively related to pH value (P〈0.01) and positively related to water loss rate (P〈0.05); the water loss rate was negatively related to pH value (P〈0.01) and lactic acid content (P〈0.05).
文摘Wnts are a large family of growth factors that mediate essential biological processes like embryogenesis, morpho- genesis and organogenesis. These proteins also play a role in oncogenesis, and they regulate apoptosis in many tissues. Wnts bind to a membrane receptor complex comprised of a frizzled (FZD) G-protein-coupled receptor and a low-density lipoprotein (LDL) receptor-related protein (LRP). The formation of this ligand-receptor complex initiates a number of signaling cascades that include the canonical/beta-catenin pathway as well as several noncanonical pathways. In recent years, canonical Wnt signaling has been reported to play a significant role in the control of bone formation. Clinical studies have found that mutations in LRP-5 are associated with reduced bone mineral density (BMD) and fractures. Investigations of knockout and transgenic mouse models of Wnt pathway components have shown that canonical Wnt signaling modulates most aspects ofosteoblast physiology including proliferation, differentiation, function and apoptosis. Transgenic mice expressing a gain of function mutant of LRP-5 in bone, or mice lacking the Wnt antagonist secreted frizzled-related protein-l, exhibit elevated BMD and suppressed osteoblast apoptosis. In addition, preclinical studies with pharmacologic compounds such as those that inhibit glycogen synthase kinase-3β support the importance of the canonical Wnt pathway in modulation of bone formation and osteoblast apoptosis.
基金the DST-SERB Major Research Project,New Delhi,India[Project File No.SB/YS/LS-109/2014]for funding this projectthe Management of A.V.V.M.Sri Pushpam College(Autonomous)+1 种基金Poondi,and Sharmila Institute of Medicinal Products Research Academy(SIMPRA)Thanjavur,India,for providing necessary facilities and support in carrying out this work
文摘In this study, molecular interactions of the ligands, quercetin, gallic acid, and metformin with various diabetes mellitus-related protein targets, such as glycogen phosphorylase and peroxisome proliferatoractivated receptor gamma, were assessed. It was revealed that quercetin possesses good binding affinity to both targets. Quercetin is a major constituent of methanolic extracts of Phyllanthus emblica fruit. The antihyperglycemic effect of quercetin in streptozotocin(STZ)-induced diabetic rats was examined. The isolated quercetin administered at a dose of 75 mg/kg body weight produced a maximum decrease of14.78% in blood glucose levels in the diabetic rats after 7 days of treatment. Furthermore, quercetin doses of 50 and 75 mg/kg were shown to significantly improve the profiles of triglycerides, high-density lipoprotein, very-low-density lipoprotein, low-density lipoprotein, and total cholesterol at the end of the study in STZ-induced diabetic rats. The administration of quercetin(25, 50, and 75 mg/kg body weight)daily for 28 days in STZ-induced diabetic rats resulted in a significant decrease in blood glucose and urine sugar levels, with a considerable rise in plasma insulin and hemoglobin levels. Therefore, quercetin is a potential drug with antidiabetic and antihyperglycemic action mediated by changes in the levels of glucose, cholesterol, and triglycerides as indicated by in silico and in vivo studies.
文摘Glycogen storage diseases (GSD) are inherited metabolic disorders of glycogen metabolism. Different hormones, including insulin, glucagon, and cortisol regulate the relationship of glycolysis, gluconeogenesis and glycogen synthesis. The overall GSD incidence is estimated 1 case per 20000-43000 live births. There are over 12 types and they are classified based on the enzyme deficiency and the affected tissue. Disorders of glycogen degradation may affect primarily the liver, the muscle, or both. Type I a involves the liver, kidney and intestine (and I b also leukocytes), and the clinical manifestations are hepatomegaly, failure to thrive, hypoglycemia, hyperlactatemia, hyperuricemia and hyperlipidemia. Type Ilia involves both the liver and muscle, and lib solely the liver. The liver symptoms generally improve with age. Type IV usually presents in the first year of life, with hepatomegaly and growth retardation. The disease in general is progressive to cirrhosis. Type Ⅵ and Ⅳ are a heterogeneous group of diseases caused by a deficiency of the liver phosphorylase and phosphorylase kinase system. There is no hyperuricemia or hyperlactatemia. Type Ⅺ is characterized by hepatic glycogenosis and renal Fanconi syndrome. Type Ⅱ is a prototype of inborn lysosomal storage diseases and involves many organs but primarily the muscle. Types V and Ⅶ involve only the muscle.
基金supported by the National Natural Science Foundation of China (No. 50508011).
文摘Polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) protocol was employed for revealing microbial community structure and succession in a sequential anaerobic and aerobic reactor performing enhanced biological phosphorus removal (EBPR) during start-up period. High phosphorus removal was achieved after 15 d. On day 30, phosphorus removal efficiency reached to 83.2% and the start-up was finished. DGGE profiles of periodical sludge samples showed that dominant microbial species were 19 OTUs (operational taxonomy units). Unweighted pair-group method using arithmetic averages (UPGMA) clustering analysis revealed that rapid community succession correlated to low phosphorus removal rate and high phosphorus removal efficiency reflected on steady community structure. Sequencing results indicated that determined sequences (12 OTUs) belonged to Proteobacterium, Actinobacteria, Gemmatimonadales and unaffiliate group. Proteobacterium, Tetrasphaera elongate and Gemmatimonas aurantiaca may act important roles in phosphorus removal. With little amount as known glycogen accumulating organisms, Candidatus Competibacter phosphatis still at accumulating-phase had limited effect on microbial community structure. When climax community was obtained, dominant microbes were 14 OTUs. Microbes in a large amount were uncultured bacterium Thauera sp., uncultured y-Proteobacterium and Tetrasphaera elongata.
文摘Diabetes mellitus affects virtually every organ system in the body and the degree of organ involvement depends on the duration and severity of the disease,and other co-morbidities.Gastrointestinal(GI) involvement can present with esophageal dysmotility,gastro-esophageal reflux disease(GERD),gastroparesis,enteropathy,non alcoholic fatty liver disease(NAFLD) and glycogenic hepatopathy.Severity of GERD is inversely related to glycemic control and management is with prokinetics and proton pump inhibitors.Diabetic gastroparesis manifests as early satiety,bloating,vomiting,abdominal pain and erratic glycemic control.Gastric emptying scintigraphy is considered the gold standard test for diagnosis.Management includes dietary modifications,maintaining euglycemia,prokinetics,endoscopic and surgical treatments.Diabetic enteropathy is also common and management involves glycemic control and symptomatic measures.NAFLD is considered a hepatic manifestation of metabolic syndrome and treatment ismainly lifestyle measures,with diabetes and dyslipidemia management when coexistent.Glycogenic hepatopathy is a manifestation of poorly controlled type 1 diabetes and is managed by prompt insulin treatment.Though GI complications of diabetes are relatively common,awareness about its manifestations and treatment options are low among physicians.Optimal management of GI complications is important for appropriate metabolic control of diabetes and improvement in quality of life of the patient.This review is an update on the GI complications of diabetes,their pathophysiology,diagnostic evaluation and management.
基金supported by Medical Fund of Zhejiang Province(No.2013KYA207)Shaoxing Science and Technology Bureau Program(No.2011A23013 and No.2013B70079)
文摘Objective:To analyze the expression of phosphatidylinositol 3 kinase(PI3-K),protein kinase B(PKB)and glycogen synthase kinase 3 beta(GSK-3β)in skeletal muscle tissue of gestational diabetes mellitus(GDM).Methods:A total of 90 cases of pregnant women were divided into observation group and control group according to the occurrence of GDM with 45 cases in either,and the expression of PI3-K,PKB,GSK-3βmRNA expression in skeletal muscle tissue was compared between two groups.Results:The total PI3-K p85 protein was significantly higher in the observation group compared with the control group,the activity of PI3-K was lower than that of the latter;The total PKB,GSK-3βprotein in skeletal tissue had no significant difference between two groups,while the serine phosphorylation levels of PKB and GSK-3βwere significantly lower in observation group compared with the control group.Conclusions:The downregulation of PI3-K,PKB and GSK-3βin skeletal tissue of GDM caused by phosphorylation dysfunction of signaling molecules is the reason for insulin resistance and transporter function decline which lead to GDM.
文摘Although glycogen synthase kinase-3 (GSK-3) might act as a tumor suppressor since its inhibition is expected to mimic the activation of Wnt-signaling pathway, GSK-3β may contribute to NF-κB activation in cancer cells leading to increased cancer cell proliferation and survival. Here we report that GSK-3β activity was involved in the proliferation of human ovarian cancer cell both in vitro and in vivo. Inhibition of GSK-3 activity by pharmacological inhibitors suppressed proliferation of the ovarian cancer cells. Overexpressing constitutively active form of GSK-3β induced entry into the S phase, increased cyclin D1 expression and facilitated the proliferation of ovarian cancer cells. Furthermore, GSK-3 inhibition prevented the formation of the tumor in nude mice generated by the inoculation of human ovarian cancer cells. Our findings thus suggest that GSK-3β activity is important for the proliferation of ovarian cancer cells, implicating this kinase as a potential therapeutic target in ovarian cancer.
基金Supported by the National Natural Science Foundation of China(No.81371039)Shanghai Natural Science Foundation(No.18ZR1440200)
文摘AIM: To investigate the regulatory mechanism of glycogen synthase kinase 3β(GSK3β) in epithelialmesenchymal transition(EMT) process after proliferative vitreoretinopathy(PVR) induction. METHODS: Experimental PVR was induced by intravitreal injection of retinal pigment epithelium(RPE) cells in the eyes of rabbits. A PI3 K/Akt inhibitor(wortmannin) and a GSK3β inhibitor(Li Cl) were also injected at different time during PVR progress. Electroretinogram(ERG), ocular fundus photographs, and B-scan ultrasonography were used to observe the PVR progress. Western blot test on the extracted retina were performed at 1, 2, 4 wk. The expression of the mesenchymal marker vimentin was determined by immunohistochemistry. Toxicity of wortmannin and Li Cl were evaluated by ERG and Td Tmediated d UTP nick-end labeling(TUNEL) assay. The vitreous was also collected for metabolomic analysis. RESULTS: Experimental PVR could significantly lead to EMT, along with the suppressed expression of GSK3β and the activation of Wnt/β-catenin and PI3 K/Akt pathways. It was verified that upregulating the expression of GSK3β could effectively inhibit EMT process by suppressing Wnt/β-catenin and PI3 K/Akt pathways. CONCLUSION: GSK3β effectively inhibits EMT via the Wnt/β-catenin and PI3 K/Akt pathways. GSK3β may be regarded as a promising target of experimental PVR inhibition.
文摘As a major microtubule-associated protein, tau plays an important role in promoting microtubule assembly and stabilizing microtubules. In Alzheimer’s disease(AD) and other tauopathies, the abnormally hyperphosphorylated tau proteins are aggregated into paired helical filaments and accumulated in the neurons with the form of neurofibrillary tangles. An imbalanced regulation in protein kinases and protein phosphatases is the direct cause of tau hyperphosphorylation. Among various kinases and phosphatases, glycogen synthase kinase-3β(GSK-3β) and protein phosphatase 2A(PP2A) are the most implicated. Accumulation of the hyperphosphorylated tau induces synaptic toxicity and cognitive impairments. Here, we review the upstream factors or pathways that can regulate GSK-3β or PP2A activity mainly based on our recent findings. We will also discuss the mechanisms that may underlie tau-induced synaptic toxicity.
基金supported by the National Natural Science Foundation of China,No.81730033(to XPG),No.81701371(to TJX)
文摘Isoflurane and sevoflurane are both inhalation anesthetics,but in clinical application,sevoflurane has been considered to be less suitable for long-term anesthesia because of its catabolic compounds and potential nephrotoxicity.Nevertheless,recent studies have shown that these two inhalation anesthetics are similar in hepatorenal toxicity,cost,and long-term anesthetic effect.Moreover,sevoflurane possibly has less cognitive impact on young mice.In this study,C57BL/6 mice aged 8–10 weeks were exposed to 1.2%isoflurane or 2.4%sevoflurane for 6 hours.Cognitive function and memory were examined in young mice using the novel object recognition,contextual fear conditioning,and cued-fear extinction tests.Western blot assay was performed to detect expression levels of D1 dopamine receptor,catechol-O-methyltransferase,phospho-glycogen synthase kinase-3β,and total glycogen synthase kinase-3βin the hippocampus.Our results show that impaired performance was not detected in mice exposed to sevoflurane during the novel object recognition test.Contextual memory impairment in the fear conditioning test was shorter in the sevoflurane group than the isoflurane group.Long-term sevoflurane exposure did not affect memory consolidation,while isoflurane led to memory consolidation and reduced retention.Downregulation of hippocampal D1 dopamine receptors and phosphorylated glycogen synthase kinase-3β/total glycogen synthase kinase-3βand upregulation of catechol-O-methyltransferase may be associated with differing memory performance after exposure to isoflurane or sevoflurane.These results confirm that sevoflurane has less effect on cognitive impairment than isoflurane,which may be related to expression of D1 dopamine receptors and catechol-O-methyltransferase and phosphorylation of glycogen synthase kinase-3βin the hippocampus.This study was approved by the Institutional Animal Care and Use Committee,Nanjing University,China on November 20,2017(approval No.20171102).
基金supported by the National Natural Science Foundation of China,No.81373741a grant from the Chinese Medicine and Integrated Medicine Research Projects funded by the Health and Family Planning Commission of Hubei Province of China,No.24a grant from the Hubei Provincial Collaborative Innovation Center of Preventive Treatment by Acupuncture and Moxibustion of China in 2014,No.8
文摘Acupuncture has been shown to ameliorate cognitive impairment of Alzheimer’s disease.Acupoints and stimulation frequency influence the therapeutic effect of electroacupuncture.Rat models of Alzheimer’s disease were established by injecting amyloid beta 1–42(Aβ_(1–42))into the bilateral lateral ventricles.Electroacupuncture at 2,30,and 50 Hz was carried out at Baihui(GV20;15°obliquely to a depth of 2mm)and Shenshu(BL23;perpendicularly to 4–6 mm depth),once a day for 20 minutes(each),for 15 days,taking a break every 7 days.The Morris water maze test was conducted to assess the learning and memory.The expression levels of glycogen synthase kinase-3β(GSK-3β),p Ser9-GSK-3β,p Tyr216-GSK-3β,amyloid precursor protein and Aβ_(1–40) in the hippocampus were determined by western blot assay.Results demonstrated that electroacupuncture treatment at different frequencies markedly improved learning and memory ability,increased synaptic curvatures,decreased the width of synaptic clefts,thickened postsynaptic densities,and downregulated the expression of GSK-3β,amyloid precursor protein,and Aβ_(1–40).pSer9-GSK-3βexpression markedly decreased,while p Tyr216-GSK-3βexpression increased.High-frequency(50 Hz)electroacupuncture was more effective than low(2 Hz)or medium-frequency(30 Hz)electroacupuncture.In conclusion,electroacupuncture treatment exerts a protective effect against Aβ_(1–42)-induced learning and memory deficits and synapse-ultrastructure impairment via inhibition of GSK-3βactivity.Moreover,high-frequency electroacupuncture was the most effective therapy.