ObjectiveThe malaria parasites remodel the host erythrocyte structure by exporting parasite proteins that interact with the membrane skeleton proteins of red blood cells (RBCs), facilitating their intracellular survival and pathogenicity. Skeleton-binding protein 1 (SBP1) is a conserved exported protein across Plasmodium species. In Plasmodium falciparum, SBP1 has been reported to interact with erythrocyte membrane skeleton proteins 4.1R and spectrin, while its contribution to erythrocyte remodeling and parasite virulence in Plasmodium berghei (Pb) remains unclear. This study aims to determine whether PbSBP1 associates with the host cytoskeletal protein 4.1R and to investigate its role in the remodeling of host RBCs and the pathogenicity of Plasmodium berghei. MethodsIn Plasmodium berghei, the relationship between PbSBP1 and the erythrocyte cytoskeletal protein 4.1R was examined using co-immunoprecipitation. A Pbsbp1 gene knockout mutant of Plasmodium berghei (Pbsbp1∆) was generated based on the principle of double crossover homologous recombination. The deformability of erythrocytes infected with Pbsbp1∆ parasites was assessed using microfluidic methods. Microchannels with an array of cylindrical pillars were used to detect modifications in infected RBC deformability. The infected RBCs were squashed between the rows and recovered between the columns and the transit velocity (μm/s) of infected RBCs travelling through the microchannel was recorded. The component of the erythrocyte membrane skeleton junctional complex, tropomodulin (TMOD), was fluorescently labeled, and the cytoskeletal network of infected erythrocytes was imaged using super-resolution stochastic optical reconstruction microscopy (STORM) to analyze ultrastructural changes in the cytoskeleton of wild-type (WT) and Pbsbp1∆-infected erythrocytes. Actin-based junctional complexes were displayed as individual clusters by the labeled TMOD in the STORM images, and the cluster densities and distances between adjacent clusters of infected RBCs were calculated. Additionally, rodent malaria models (BALB/c mice) and experimental cerebral malaria models (C57BL/6 mice) were employed to monitor the growth of Pbsbp1∆ and WT parasites during the intraerythrocytic stage and their capacity to induce cerebral malaria in mice. ResultsPbSBP1 may participate in the remodeling of infected erythrocytes through direct or indirect interaction with the erythrocyte cytoskeletal protein 4.1R. Microfluidic assays revealed that the deformability of erythrocytes infected with Pbsbp1∆ parasites was significantly enhanced compared to those infected with WT parasites. STORM imaging further demonstrated that the ultrastructure of the erythrocyte cytoskeleton in Pbsbp1∆-infected cells was altered relative to that in WT-infected erythrocytes. The distances between nearest neighbors of clusters had a tendency to increase while the cluster densities were decreased in Pbsbp1∆-infected RBCs compared to WT-infected RBCs. Subsequent phenotypic analysis indicated that the growth rate of Pbsbp1∆ parasites during the intraerythrocytic stage was significantly slower than that of WT parasites, and their ability to induce cerebral malaria in mice was also attenuated. These findings suggest that PbSBP1 is involved in the remodeling of the erythrocyte membrane skeleton, likely through its direct or indirect interaction with protein 4.1R, thereby regulating the deformability of infected erythrocytes and influencing the pathogenicity of the blood-stage parasites. ConclusionThis study establishes a role for PbSBP1 in host erythrocyte remodeling and parasite virulence, providing new research strategies for the prevention and treatment of malaria.

AIM To investigate the mechanism of Jiedu Yizhi Formula on cognitive function and neuroinflammation in a mouse model of Alzheimer's disease(AD).METHODS 50 APP/PS1 double transgenic mice were randomly divided into the model group,the donepezil group,and the low-dose,moderate-dose,and high-dose Jiedu Yizhi Formula group(1.78,3.56 and 7.12 g/kg),with 10 mice in each group,in contrast to the 10 WT mice of the blank group.Following anesthesia administration and 8-week oral gavage regimen with respective drugs,all mice underwent final tissue sample collection.The mice had their learning and memory ability assessed by Morris water maze and nesting behavior scores;their pathology of brain tissue and Aβ expression observed using HE,Nissl and IHC staining;their polarization of microglia and the expression of inflammatory factors in hippocampal tissue detected by IF and ELISA;their hippocampal expression of PI3K/Akt/mTOR signaling pathway detected by RT-qPCR and Western blot.RESULTS Compared with the blank group,the model group had lower scores in total swimming distance,frequency in crossing the platform,residence time in the target quadrant,and nesting behavior scores(P＜0.05,P＜0.01);prolonged evasion latency(P＜0.01);more disorganized arrangement of pyramidal cells,solidification and deep staining,unclear demarcation,irregular cell shapes,reduction of Nyctinidia,and increased Aβ deposition in the brain tissue(P＜0.01);elevated expression of hippocampal microglia M1-type markers CD16/32 and lba-1(P＜0.01);decreased levels of M2-type marker CD206(P＜0.05);elevated levels of TNF-α and IL-1β(P＜0.01);decreased expressions of IL-13 and IL-4(P＜0.01);and decreased levels of PI3K,Akt and mTOR mRNA,and reduced p-PI3K,p-Akt and p-mTOR protein expressions(P＜0.01).Compared to the model group,the donepezil group and the Jiedu Yizhi Formula groups showed statistically significant improvements in the aforementioned indexes(P＜0.05,P＜0.01),with the magnitude of improvement being higher in the high-dose Jiedu Yizhi Formula group.CONCLUSION Jiedu Yizhi Formula suppresses microglia Ml-type polarization while enhancing M2-type polarization via activation the PI3K/Akt/mTOR signaling pathway,which subsequently reduces inflammatory cytokine secretion.This mechanism attenuates Aβ deposition in brain tissues and ameliorates cognitive dysfunction in AD mouse models.

Aim To investigate the regulatory mecha-nisms of donepezil on the expression and enzymatic ac-tivity of cytochrome P450 3A4(CYP3A4),elucidate the synergistic impact of hypoxia on CYP3A4 function,and reveal its potential association with drug-induced cardiotoxicity,particularly QT interval prolongation.Methods Western blot,co-immunoprecipitation,and gene knockdown techniques were employed to evaluate the effects of donepezil and hypoxia on CYP3A4 pro-tein expression.CYP3A4 enzymatic activity was as-sessed using an in vitro incubation system with rat liver microsomes combined with high-performance liquid chromatography(HPLC),and the half-maximal inhib-itory concentration(IC50)was determined.Results Donepezil(10 μmol·L-1)and hypoxia reduced CYP3A4 protein expression to 31.75％and 45.90％of the control levels,respectively.Both interventions activated the gp78-mediated ubiquitin-proteasome path-way,significantly increasing CYP3A4 ubiquitination levels by 2.1-fold compared to the control group,thereby promoting proteasomal degradation.Donepezil inhibited CYP3A4 enzyme activity with an IC50 of 83.4μmol·L-1,and hypoxia synergistically enhanced this inhibitory effect,reducing the IC50 to 20.79 μmol·L-1.Conclusion Donepezil downregulates CYP3A4 function through dual mechanisms involving ubiquitin-mediated proteasomal degradation and direct enzymatic inhibition.Hypoxia potentiates this effect,leading to impaired metabolism of CYP3A4 substrate drugs,ele-vated plasma drug concentrations(1.6-2.3-fold in-crease compared to normal metabolic conditions),and an increased risk of QT interval prolongation and other forms of cardiotoxicity.

Bovine rotavirus(BRV)is an important pathogen causing diarrhea in calves.To understand the genomic charac-teristics and genetic variations in bovine rotavirus,and to further enrich data on the biological characteristics of rotavirus,we aimed to amplify 11 gene segments of the isolated and cultured G6P[1]bovine rotavirus BLL strain,perform whole genome se-quencing,and analyze the molecular characteristics.MEGA7.0 and DNAMAN software were used for homology and typing a-nalysis,and the whole genome phylogenetic tree was constructed to analyze genetic evolution relationships.The complete geno-type of the BLL strain was G6-P[1]-I2-R2-C2-M2-A3-N2-T6-E2-H3.Phylogenetic analysis of the VP7 and VP4 genes of the BLL strain showed that the VP7 gene had the highest homology with RVA/Cow-wt/HB01/China/2021,and the VP4 gene of the BLL strain was in the same branch as RVA/Human-tc/ISR/Ro8059/1995.From the sequence alignment of VP8*amino acids,the sialic acid domain of the BLL strain was found to be similar to that in other P[1]strains,but different from those in other types of strains,except for residue 189,which was the same as that in Ro8059 but different from that in other strains.The results suggested that the BLL strain might potentially infect humans.Therefore,continued monitoring and study of the biological characteristics of this strain are necessary to provide more information and evidence supporting further research on the cross-species transmission of group A rotavirus in China.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Objective To develop and validate a transgenic mouse model enabling specific and inducible optogenetic activation of oligodendrocyte precursor cells(OPCs).Methods A conditional allele for the photosensitive opsin chicken opsin 5(cOpn5)(Rosa26-LSL-cOpn5)was generated using CRISPR/Cas9 technology.These mice were subsequently crossed with NG2-CreERT transgenic mice to produce NG2-CreERT;cOpn5 animals.In this model,tamoxifen administration induces Cre-mediated recombination,leading to specific expression of cOpn5 in NG2-positive OPCs.The specificity and efficiency of cOpn5 expression in OPCs were confirmed by immunofluorescent staining.Functional validation of light-induced OPC activation was performed by using calcium imaging in acute brain slices after stimulation with 470 nm blue light.Results Immunofluorescence analysis confirmed robust and specific expression of cOpn5 within NG2-positive OPCs in the brains of tamoxifen-treated NG2-CreERT;cOpn5 mice.Crucially,calcium imaging of acute brain slices from these mice demonstrated a significant increase in intracellular calcium levels in cOpn5-expressing OPCs upon stimulation with 470 nm blue light,indicating successful optogenetic activation.Conclusion We have successfully generated and validated a novel transgenic mouse model(NG2-CreERT;cOpn5)that permits specific and inducible optogenetic activation of OPCs.This model provides a novel tool for subsequent in vivo studies of the role and regulating mechanisms of OPCs in the central nervous system.

Aim To investigate the mechanism by which Aiweixin oral liquid(AWX)alleviates myocar-dial ischemia-reperfusion injury in rats through the reg-ulation of mitochondrial fusion and fission.Methods Seventy-two healthy male Sprague-Dawley rats were randomly assigned to six groups(n=12)using a ran-dom number table:sham surgery group,model group,low-dose AWX(1 mL·kg-1)group,medium-dose AWX(2 mL·kg-1)group,high-dose AWX(4 mL·kg-1)group,and positive control drug trimetazidine(10 mg·kg-1)group.A myocardial ischemia-reper-fusion injury(MIRI)model was established by ligating the left anterior descending coronary artery of the rat heart,followed by 30 minutes of ischemia and 90 mi-nutes of reperfusion.In the sham surgery group,only a suture was placed without ligation.The rats in the treatment groups were pre-gavaged with AWX starting 10 days prior to the modeling procedure.Lead Ⅱ elec-trocardiograms were recorded before and after reperfu-sion in each group to observe the changes in electrocar-diographic parameters.The myocardial infarct size in each group was assessed using TTC staining.The his-topathological changes in myocardial tissue were exam-ined under a light microscope using hematoxylin and eosin(HE)staining.The serum levels of adenosine triphosphate(ATP)and cardiac troponin I(cTnI)were measured using enzyme-linked immunosorbent as-say(ELISA).Superoxide dismutase(SOD)activity and the levels of malondialdehyde(MDA)and lactate dehydrogenase(LDH)were determined using bio-chemical assay kits.The protein expression levels of dynamin-related protein 1(dynamin-relatedprotein 1,DRP1),mitochondrial fission factor(mitochondrial fis-sion factor,MFF),mitochondrial fission protein 1(mi-tochondrial fission protein 1,FIS1),mitofusin 1(mito-fusion-1,MFN1),and mitofusin 2(mitofusion-2,MFN2)were evaluated by Western blot analysis.Re-sults Compared with the sham group,the model group exhibited aggravated myocardial tissue pathological damage,an increased percentage of myocardial infarct size,decreased serum SOD activity and ATP levels,and significantly elevated levels of MDA,cTnI,and LDH activity.Additionally,the protein expression of mito-chondrial fission factors DRP1,MFF,and FIS1 was up-regulated,while the expression of fusion-related factors MFN1 and MFN2 was downregulated.Compared with the model group,Aiweixin oral liquid significantly alle-viated myocardial injury,reduced the percentage of my-ocardial infarct size,increased serum SOD activity and ATP levels,decreased MDA content and cTnI and LDH activity,downregulated the protein expression of mito-chondrial fission factors DRP1,MFF,and FIS1,and up-regulated the protein expression of fusion-related factors MFN1 and MFN2.Conclusion Aiweixin oral liquid alleviates myocardial ischemia-reperfusion injury in rats by regulating abnormal mitochondrial fusion and fis-sion.

The ocean plays a critical role in the global carbon cycle,and base on the"dual carbon"goals,ocean carbon sinks have received widespread attention.Shellfish aquaculture is one of the most important sources of carbon sinks in fisheries,which has an important impact on the offshore carbon cy-cle.As global temperature rises and ocean acidification intensifies,the capacity of the ocean to absorb CO2 will change.However,the effects of high temperature on the physiology and transcriptome related to carbon metabolism in Mytilus coruscus are not clear enough.This study investigated the effects of high temperatures on the total carbon content,carbon metabolism,antioxidant-related enzyme activities,and the transcriptome of Mytilus coruscus.The results showed that high temperature significantly inhibited the activities of hexokinase and pyruvate kinase,increased carbonic anhydrase activity(P＜0.05),de-creased the ATP content of digestive glands(P＜0.05),and affected glycolysis and the tricarboxylic acid cycle,leading to a significant decrease in the mussel's ability to sequester carbon.High temperature re-sulted in significant(P＜0.05)increases in the levels of reactive oxygen species and malondialdehyde,and enhanced the activities of superoxide dismutase and catalase.Observations by transmission electron microscopy showed that high temperatures damaged the subcellular structure of the digestive gland in Mytilus coruscus,resulting in the shrinkage of the nucleolus,swelling of the endoplasmic reticulum,and a significant reduction in the mitochondrial cristae.Comparative transcriptomic analysis showed that the upregulated DEGs were mainly enriched in protein processing in the endoplasmic reticulum,antigen pro-cessing and presentation,and MAPK signaling pathway.The downregulated DEGs were mainly enriched in necroptosis,DNA replication,and the NF-kappa B signaling pathway.In antioxidant-related DEGs,the upregulated DEGs include vitamin K epoxide reductase,peroxidases,heat shock protein 105 kD,heat shock protein 70 kD,and superoxide dismutase;The downregulated DEGs mainly included NADPH oxidase,glutathione reductase,cytochrome b-245,cytochrome P450,and quinone reductase.The up-regulated genes enriched in the carbon metabolism pathway included chitinase,phosphatidylinositol 4,5-bisphosphate 3-kinase,phosphoenolpyruvate carboxykinase,galactokinase,and inositol trisphosphate 3-kinase.The downregulated genes included aldose-1-epimerase,carbonic anhydrase,galactose mutaro-tase,acyl-CoA synthetase,alcohol dehydrogenase,and hexokinase.In conclusion,high temperature has an inhibitory effect on the activities of enzymes and the expression of genes related to carbon metabolism in Mytilus coruscus.The results of this study are intended to provide a scientific basis for the healthy de-velopment of mussel aquaculture and the assessment of carbon sinks.

Aim To investigate the mechanism by which Aiweixin oral liquid(AWX)alleviates myocar-dial ischemia-reperfusion injury in rats through the reg-ulation of mitochondrial fusion and fission.Methods Seventy-two healthy male Sprague-Dawley rats were randomly assigned to six groups(n=12)using a ran-dom number table:sham surgery group,model group,low-dose AWX(1 mL·kg-1)group,medium-dose AWX(2 mL·kg-1)group,high-dose AWX(4 mL·kg-1)group,and positive control drug trimetazidine(10 mg·kg-1)group.A myocardial ischemia-reper-fusion injury(MIRI)model was established by ligating the left anterior descending coronary artery of the rat heart,followed by 30 minutes of ischemia and 90 mi-nutes of reperfusion.In the sham surgery group,only a suture was placed without ligation.The rats in the treatment groups were pre-gavaged with AWX starting 10 days prior to the modeling procedure.Lead Ⅱ elec-trocardiograms were recorded before and after reperfu-sion in each group to observe the changes in electrocar-diographic parameters.The myocardial infarct size in each group was assessed using TTC staining.The his-topathological changes in myocardial tissue were exam-ined under a light microscope using hematoxylin and eosin(HE)staining.The serum levels of adenosine triphosphate(ATP)and cardiac troponin I(cTnI)were measured using enzyme-linked immunosorbent as-say(ELISA).Superoxide dismutase(SOD)activity and the levels of malondialdehyde(MDA)and lactate dehydrogenase(LDH)were determined using bio-chemical assay kits.The protein expression levels of dynamin-related protein 1(dynamin-relatedprotein 1,DRP1),mitochondrial fission factor(mitochondrial fis-sion factor,MFF),mitochondrial fission protein 1(mi-tochondrial fission protein 1,FIS1),mitofusin 1(mito-fusion-1,MFN1),and mitofusin 2(mitofusion-2,MFN2)were evaluated by Western blot analysis.Re-sults Compared with the sham group,the model group exhibited aggravated myocardial tissue pathological damage,an increased percentage of myocardial infarct size,decreased serum SOD activity and ATP levels,and significantly elevated levels of MDA,cTnI,and LDH activity.Additionally,the protein expression of mito-chondrial fission factors DRP1,MFF,and FIS1 was up-regulated,while the expression of fusion-related factors MFN1 and MFN2 was downregulated.Compared with the model group,Aiweixin oral liquid significantly alle-viated myocardial injury,reduced the percentage of my-ocardial infarct size,increased serum SOD activity and ATP levels,decreased MDA content and cTnI and LDH activity,downregulated the protein expression of mito-chondrial fission factors DRP1,MFF,and FIS1,and up-regulated the protein expression of fusion-related factors MFN1 and MFN2.Conclusion Aiweixin oral liquid alleviates myocardial ischemia-reperfusion injury in rats by regulating abnormal mitochondrial fusion and fis-sion.

The ocean plays a critical role in the global carbon cycle,and base on the"dual carbon"goals,ocean carbon sinks have received widespread attention.Shellfish aquaculture is one of the most important sources of carbon sinks in fisheries,which has an important impact on the offshore carbon cy-cle.As global temperature rises and ocean acidification intensifies,the capacity of the ocean to absorb CO2 will change.However,the effects of high temperature on the physiology and transcriptome related to carbon metabolism in Mytilus coruscus are not clear enough.This study investigated the effects of high temperatures on the total carbon content,carbon metabolism,antioxidant-related enzyme activities,and the transcriptome of Mytilus coruscus.The results showed that high temperature significantly inhibited the activities of hexokinase and pyruvate kinase,increased carbonic anhydrase activity(P＜0.05),de-creased the ATP content of digestive glands(P＜0.05),and affected glycolysis and the tricarboxylic acid cycle,leading to a significant decrease in the mussel's ability to sequester carbon.High temperature re-sulted in significant(P＜0.05)increases in the levels of reactive oxygen species and malondialdehyde,and enhanced the activities of superoxide dismutase and catalase.Observations by transmission electron microscopy showed that high temperatures damaged the subcellular structure of the digestive gland in Mytilus coruscus,resulting in the shrinkage of the nucleolus,swelling of the endoplasmic reticulum,and a significant reduction in the mitochondrial cristae.Comparative transcriptomic analysis showed that the upregulated DEGs were mainly enriched in protein processing in the endoplasmic reticulum,antigen pro-cessing and presentation,and MAPK signaling pathway.The downregulated DEGs were mainly enriched in necroptosis,DNA replication,and the NF-kappa B signaling pathway.In antioxidant-related DEGs,the upregulated DEGs include vitamin K epoxide reductase,peroxidases,heat shock protein 105 kD,heat shock protein 70 kD,and superoxide dismutase;The downregulated DEGs mainly included NADPH oxidase,glutathione reductase,cytochrome b-245,cytochrome P450,and quinone reductase.The up-regulated genes enriched in the carbon metabolism pathway included chitinase,phosphatidylinositol 4,5-bisphosphate 3-kinase,phosphoenolpyruvate carboxykinase,galactokinase,and inositol trisphosphate 3-kinase.The downregulated genes included aldose-1-epimerase,carbonic anhydrase,galactose mutaro-tase,acyl-CoA synthetase,alcohol dehydrogenase,and hexokinase.In conclusion,high temperature has an inhibitory effect on the activities of enzymes and the expression of genes related to carbon metabolism in Mytilus coruscus.The results of this study are intended to provide a scientific basis for the healthy de-velopment of mussel aquaculture and the assessment of carbon sinks.