Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Background/Aims: Metabolic dysfunction-associated steatohepatitis (MASH) is a significant risk factor for gallstone formation, but mechanisms underlying MASH-related gallstone formation remain unclear. Golgi membrane protein 1 (GOLM1) participates in hepatic cholesterol metabolism and is upregulated in MASH. Here, we aimed to explore the role of GOLM1 in MASH-related gallstone formation. Methods: The UK Biobank cohort was used for etiological analysis. GOLM1 knockout (GOLM1-/-) and wild-type (WT) mice were fed with a high-fat diet (HFD). Livers were excised for histology and immunohistochemistry analysis. Gallbladders were collected to calculate incidence of cholesterol gallstones (CGSs). Biles were collected for biliary lipid analysis. HepG2 cells were used to explore underlying mechanisms. Human liver samples were used for clinical validation. Results: MASH patients had a greater risk of cholelithiasis. All HFD-fed mice developed MASH, and the incidence of gallstones was 16.7% and 75.0% in GOLM1-/- and WT mice, respectively. GOLM1-/- decreased biliary cholesterol concentration and output. In vivo and in vitro assays confirmed that GOLM1 facilitated cholesterol efflux through upregulating ATP binding cassette transporter subfamily G member 5 (ABCG5). Mechanistically, GOLM1 translocated into nucleus to promote osteopontin (OPN) transcription, thus stimulating ABCG5-mediated cholesterol efflux. Moreover, GOLM1 was upregulated by interleukin-1β (IL-1β) in a dose-dependent manner. Finally, we confirmed that IL-1β, GOLM1, OPN, and ABCG5 were enhanced in livers of MASH patients with CGSs. Conclusions In MASH livers, upregulation of GOLM1 by IL-1β increases ABCG5-mediated cholesterol efflux in an OPN-dependent manner, promoting CGS formation. GOLM1 has the potential to be a molecular hub interconnecting MASH and CGSs.

Background/Aims: Metabolic dysfunction-associated steatohepatitis (MASH) is a significant risk factor for gallstone formation, but mechanisms underlying MASH-related gallstone formation remain unclear. Golgi membrane protein 1 (GOLM1) participates in hepatic cholesterol metabolism and is upregulated in MASH. Here, we aimed to explore the role of GOLM1 in MASH-related gallstone formation. Methods: The UK Biobank cohort was used for etiological analysis. GOLM1 knockout (GOLM1-/-) and wild-type (WT) mice were fed with a high-fat diet (HFD). Livers were excised for histology and immunohistochemistry analysis. Gallbladders were collected to calculate incidence of cholesterol gallstones (CGSs). Biles were collected for biliary lipid analysis. HepG2 cells were used to explore underlying mechanisms. Human liver samples were used for clinical validation. Results: MASH patients had a greater risk of cholelithiasis. All HFD-fed mice developed MASH, and the incidence of gallstones was 16.7% and 75.0% in GOLM1-/- and WT mice, respectively. GOLM1-/- decreased biliary cholesterol concentration and output. In vivo and in vitro assays confirmed that GOLM1 facilitated cholesterol efflux through upregulating ATP binding cassette transporter subfamily G member 5 (ABCG5). Mechanistically, GOLM1 translocated into nucleus to promote osteopontin (OPN) transcription, thus stimulating ABCG5-mediated cholesterol efflux. Moreover, GOLM1 was upregulated by interleukin-1β (IL-1β) in a dose-dependent manner. Finally, we confirmed that IL-1β, GOLM1, OPN, and ABCG5 were enhanced in livers of MASH patients with CGSs. Conclusions In MASH livers, upregulation of GOLM1 by IL-1β increases ABCG5-mediated cholesterol efflux in an OPN-dependent manner, promoting CGS formation. GOLM1 has the potential to be a molecular hub interconnecting MASH and CGSs.

Background/Aims: Metabolic dysfunction-associated steatohepatitis (MASH) is a significant risk factor for gallstone formation, but mechanisms underlying MASH-related gallstone formation remain unclear. Golgi membrane protein 1 (GOLM1) participates in hepatic cholesterol metabolism and is upregulated in MASH. Here, we aimed to explore the role of GOLM1 in MASH-related gallstone formation. Methods: The UK Biobank cohort was used for etiological analysis. GOLM1 knockout (GOLM1-/-) and wild-type (WT) mice were fed with a high-fat diet (HFD). Livers were excised for histology and immunohistochemistry analysis. Gallbladders were collected to calculate incidence of cholesterol gallstones (CGSs). Biles were collected for biliary lipid analysis. HepG2 cells were used to explore underlying mechanisms. Human liver samples were used for clinical validation. Results: MASH patients had a greater risk of cholelithiasis. All HFD-fed mice developed MASH, and the incidence of gallstones was 16.7% and 75.0% in GOLM1-/- and WT mice, respectively. GOLM1-/- decreased biliary cholesterol concentration and output. In vivo and in vitro assays confirmed that GOLM1 facilitated cholesterol efflux through upregulating ATP binding cassette transporter subfamily G member 5 (ABCG5). Mechanistically, GOLM1 translocated into nucleus to promote osteopontin (OPN) transcription, thus stimulating ABCG5-mediated cholesterol efflux. Moreover, GOLM1 was upregulated by interleukin-1β (IL-1β) in a dose-dependent manner. Finally, we confirmed that IL-1β, GOLM1, OPN, and ABCG5 were enhanced in livers of MASH patients with CGSs. Conclusions In MASH livers, upregulation of GOLM1 by IL-1β increases ABCG5-mediated cholesterol efflux in an OPN-dependent manner, promoting CGS formation. GOLM1 has the potential to be a molecular hub interconnecting MASH and CGSs.

Objective To investigate the neuroprotective effect and potential mechanism of rehabilitation training combined with citicoline on cerebral hemorrhage model in mice based on Keap1/Nrf2/ARE signaling pathway.Methods The C57BL/6 male mice were randomly divided into sham operation group(sham operation treatment),model group(right caudate putamen hemorrhage model induced by type Ⅶcollagenase),choline group(model+choline 64 mg·kg-1),rehabilitation training group(rehabilitation training)and combined group(model+rehabilitation training+choline 64 mg·kg-1).The study observed the modified neurological severity score(mNSS)in mice with cerebral hemorrhage;colorimetric assays were used to detect the expression of malondialdehyde(MDA),superoxide dismutase(SOD)and catalase(CAT)in brain tissues;protein imprinting and reverse transcription-quantitative polymerase chain reaction were employed to assess the expression of Kelch-like ECH-associated protein 1(Keap1),nuclear factor erythroid 2-related factor 2(Nrf2)/antioxidant response element(ARE),heme oxygenase-1(HO-1),quinone oxidoreductase 1(NQ01)proteins and mRNA in brain tissues.Results The mNSS scores of sham operation group,model group,citicoline group,rehabilitation training group and combined group were 0,1.56±0.73,1.00±0.00,0.78±0.44 and 0.67±0.50;the MDA contents were(6.93±0.92),(22.97±0.77),(19.26±1.73),(13.21±0.78)and(7.25±0.97)nmol·mgprot-1;the relative expression of Keap1 protein were 0.79±0.03,1.02±0.04,0.95±0.10,0.90±0.09 and 0.86±0.05;the relative expression levels of Nrf2 protein were 0.94±0.12,0.71±0.08,0.90±0.07,0.98±0.12 and 1.33±0.25.There were significant differences in the above indexes between the model group and the sham operation group(P＜0.05,P＜0.01);there were significant differences between the citicoline group and the rehabilitation training group,the model group(P＜0.05,P＜0.01);there were significant differences between the combined group and the citicoline group,the rehabilitation training group except for protein expression of Keap1(all P＜0.01).Conclusion Rehabilitation training and citicoline can reduce the symptoms of neurological deficits in mice with cerebral hemorrhage.The mechanism way be that they can activate the Keap1/Nrf2/ARE signaling pathway to exert anti-oxidative stress,and the combined effect is the best.

Objective:To understand the whole genome and genetic evolution characteristics of the first epidemic influenza A (H3N2) viruses in Wuxi from 2022-2023.Methods:Real time fluorescence quantitative RT-PCR method was used to perform typing on respiratory samples of influenza cases. Virus isolation was performed on samples with positive nucleic acid of subtype A H3N2 influenza virus detected. After cell culture, nucleic acid was extracted from strains with red blood cell agglutination test (HA) ≥ 1∶8, whole genome sequence was amplified, library was constructed, and computer sequencing was performed using MiSeq sequencer. Using NC_007366.1 as reference strain, the data were analyzed using CLC Genomics Workbench (Version 23) software. The phylogenetic tree was constructed using MEGA 7.0 software, and the N-glycosylation sites were predicted by NetNGlyc 1.0 Server software.Results:The nucleotide homology and amino acid homology among 35 strains of influenza A H3N2 virus from 2022 to 2023 were 96.4%-100% and 95.2%-100%, respectively. The 16 epidemic strains in 2022 belong to the 3C.2a1b.2a.1a evolutionary branch, while the 19 epidemic strains in 2023 belong to the 3C.2a1b.2a.2a.3a.1 evolutionary branch. There are 7 differences in the nucleotide sequence of the HA gene between the 2022 epidemic strain and the corresponding vaccine strain, sharing 15 mutation sites; There are 28 differences in the nucleotide sequence of the HA gene between the 2023 epidemic strain and the corresponding vaccine strain, sharing 17 mutation sites. The HA genes of 35 epidemic strains all lack N-glycosylation site 61: NSS, while in 2023, the HA genes of 19 epidemic strains added N-glycosylation site 110: NSS.Conclusions:The HA and NA genes of influenza A H3N2 virus in 2022 and 2023 belong to two evolutionary branches, respectively, and both show specific amino acid site changes compared to the corresponding vaccine strains. The antigen matching between the 2022 epidemic strain and the vaccine strain is relatively good, while there is a risk of low antigen matching between the 2023 epidemic strain and the vaccine strain.

Objective:To analyze the clinical characteristics and all-cause mortality influencing factors of patients with Keshan disease.Methods:Clinical data of patients with Keshan disease from Keshan disease areas in Sichuan Province and Yunnan Province were collected and retrospectively analyzed for clinical characteristics and survival status during regular follow-up. According to the survival status of patients, the survey subjects were divided into a survival group and a death group. All-cause mortality (referring to the death caused by various reasons throughout the follow-up period) was used as the study endpoint. Kaplan-Meier (K-M) survival curve analysis and log-rank χ 2 test were performed, univariate and multivariate Cox regression analysis were used for all-cause mortality factor analysis. Results:A total of 176 patients with Keshan disease were collected, including 92 cases in Sichuan Province and 84 cases in Yunnan Province. Among all the patients, there were 105 males, accounting for 59.66%, and 71 females, accounting for 40.34%. The age was (53.89 ± 13.19) years old. Thirty-five cases died from all causes, with a mortality rate of 19.89%. There were significant differences in age ( t = 2.09, P = 0.038), New York Heart Association (NYHA) cardiac function grading (χ 2 = 14.62, P < 0.001) and ventricular premature contraction (χ 2 = 6.82, P = 0.009) between the survival group and the death group. K-M survival curve analysis showed that patients with Keshan disease complicated by premature ventricular contraction and high NYHA cardiac function grading (Ⅲ and Ⅳ) had higher all-cause mortality (log-rank χ 2 = 8.72, 22.49, P < 0.05). Univariate Cox regression analysis showed that NYHA cardiac function grading and ventricular premature contraction ( HR = 3.09, 2.71, P < 0.05) were predictive influencing factors for all-cause mortality in patients with Keshan disease. Multivariate Cox regression analysis showed that NYHA cardiac function grading ( HR = 6.57, P = 0.002) and ventricular premature contraction ( HR = 2.98, P = 0.050) were independent factors for all-cause mortality in patients with Keshan disease. Conclusions:Among 176 patients with Keshan disease, the number of patients with poor cardiac function (NYHA cardiac function grading Ⅲ and Ⅳ) and arrhythmia is high. NYHA cardiac function grading and ventricular premature contractions are independent influencing factors for all-cause mortality in patients with Keshan disease.

Objective:To investigate the neuroprotective effect of hesperidin combined with enriched environment on ferroptosis in collagenase-induced intracerebral hemorrhage(ICH) mouse model as well as the ferroptosis mechanism.Methods:ICH model was established by injecting collagenase Ⅶ into caudate putamen nucleus. Ninty C57BL/6J mice were randomly divided into 6 groups according to a random number table: sham group, intracerebral hemorrhage group, enriched environment group, hesperidin group, enriched environment and hesperidin group (combination group), and combination group + Nrf2 specific inhibitor ML385 (inhibitor group), with 15 mice in each group. The mice in inhibitor group, intracerebral hemorrhage group, enriched environment group, hesperidin group and combination group were injected with 0.5 μL collagenase type Ⅶ solution (0.075 U/μL, dissolved with 0.9% NaCl solutin) for ICH modeling, and the mice in sham group were injected with 0.9% normal saline. The hesperidin group, combination group, and inhibitor group were given hesperidin solution (dissolved in 0.5% carboxymethyl cellulose sodium) by gavage within 6 hours after the modeling surgery. The sham group, intracerebral hemorrhage group, and enriched environment group were given equal volumes of 0.5% carboxymethyl cellulose sodium solution by gavage. The inhibitor group was intraperitoneally injected with Nrf2 specific inhibitor ML385 (30 mg/kg, dissolved in 5% DMSO), while the other groups were intraperitoneally injected with an equal volume of 5% DMSO. Both gastric perfusion and intraperitoneal injection were completed within 6 hours after the end of modeling operation, once a day for 14 days. After the postoperative recovery of the mice, the enriched environment group, combination group, and inhibitor group were placed in enriched environment cages, while the sham group, intracerebral hemorrhage group, and hesperidin group were placed in regular cages. After all intervention were completed, all mice were evaluated using the modified neurological severity score (mNSS). Then the mice were subjected to brain water content detection, Prussian blue staining, ELISA detection of changes in malondialdehyde (MDA), superoxide dismutase (SOD), reactive oxygen species (ROS), glutathione peroxidase 4 (Gpx4), PCR and Western blot detection of nuclear factor E2 related factor 2 (Nrf2) and Gpx4 at the mRNA level and protein level. The GraphPad Prism 9 software was used for statistical analysis. ANOVA was used for multi-group comparison, and Tukey test was used for multiple comparisons.Results:(1) There was a statistically significant difference in mNSS scores among the 6 groups ( F=66.35, P<0.001). The mNSS score of the intracerebral hemorrhage group(8.00±1.46) was higher than that of the sham group(0.86±0.83)( P<0.05). The mNSS scores of the enriched environment group (6.47±1.13) and hesperidin group (6.13±1.25) were lower than that of the intracerebral hemorrhage group, but higher than that of the combination group (4.53±1.30)(all P<0.05). (2) There was a statistically significant difference in the percentage of brain water content among the 6 groups ( F=33.29, P<0.001). The percentage of brain water content in the intracerebral hemorrhage group was higher than that in the sham group.The percentage of brain water content in the enriched environment group and hesperidin group were lower than that in the intracerebral hemorrhage group, but higher than that in the combination group (all P<0.05). (3) The result of Prussian blue staining showed that iron deposition in the intracerebral hemorrhage group was higher than that in the sham group, while the iron depositions in the enriched environment group and hesperidin groups were lower than that in the intracerebral hemorrhage group, but higher than that in the combination group(all P<0.05). (4) There were statistically significant differences in the expression levels of Nrf2 and Gpx4 mRNA and protein among the 6 groups ( F=27.73, 31.24, 26.79, 13.79, all P<0.001). The mRNA and protein levels of Nrf2 and Gpx4 in the combination group were higher than those in the enriched environment group, hesperidin group, but higher than those in the inhibitor group(all P<0.05). (5) The results of ELISA showed that the levels of MDA, Gpx4, ROS, and SOD in the brain tissues of 6 groups were statistically significant ( F=111.20, 21.53, 29.45, 22.75, all P<0.001). Among them, the MDA and ROS in the combination group ((14.05±0.57) nmol/mL, (75.46±3.40) ng/mL) were lower than those in the enriched environment group ((18.17±2.51) nmol/mL, (97.23±3.43) ng/mL), hesperidin group ((17.24±0.68) nmol/mL, (90.02±9.46) ng/mL) and the inhibitor group ((17.08±0.64) nmol/mL, (101.07±3.38) ng/mL), while Gpx4 and SOD ((340.40±31.21) pg/mL, (62.55±2.81) ng/mL) were higher than those in the enriched environment group ((267.81±27.17) pg/mL, (50.47±8.38) ng/mL), hesperidin group ((271.55±34.36) pg/mL, (50.55±8.19) ng/mL) and the inhibitor group ((235.65±72.54)pg/mL, (52.67±3.56)ng/mL)(all P<0.05). Conclusion:Enriched environment and hesperidin can inhibit ferroptosis after ICH by activating the Nrf2/GPX4 pathway, exerting neuroprotective effects on ICH mouse models, and the combined treatment of the enriched environment and hesperidin has a more significant effect.

Objective:To observe the clinical efficacy of exercise-based acupuncture in treating ischemic stroke and its effects in improving the patient's motor function and daily living ability. Methods:A total of 106 patients with motor dysfunction due to cerebral infarction were randomized into a trial group and a control group,each consisting of 53 cases.Both groups received conventional rehabilitation;in addition,the control group was given point-toward-point acupuncture at scalp points,and the trial group was offered exercise-based acupuncture,3 times weekly for 4 consecutive weeks.Before treatment,after 2 and 4 weeks of treatment,and at the 2-month follow-up,the Fugl-Meyer assessment(FMA)scale,Lovett scale for muscle strength,modified Ashworth scale(MAS),and activities of daily living(ADL)scale were used to assess the patient's motor function,muscle strength,muscle tension,and daily living ability. Results:After treatment,both groups gained improvements in motor function and daily living ability;after 4-week treatment and at the 2-month follow-up,the trial group had higher FMA and ADL scores than the control group(P<0.05).The MAS score decreased after treatment in both groups;after 2 and 4 weeks of treatment and at the 2-month follow-up,the MAS score was lower in the trial group than in the control group(P<0.05).After the intervention,the Lovett score increased in both groups;after 4 weeks of treatment,the Lovett score was higher in the trial group than in the control group(P<0.05). Conclusion:Based on routine rehabilitation,exercise-based acupuncture and scalp point-toward-point acupuncture both can improve the motor function and daily living ability in ischemic stroke patients;exercise-based acupuncture performs better than scalp point-toward-point acupuncture.

Cinnamomum camphora is an important economic tree species in China. According to the type and content of main components in the volatile oil of leaf, C. camphora were divided into five chemotypes, including borneol-type, camphor-type, linalool-type, cineole-type, and nerolidol-type. Terpene synthase(TPS) is the key enzyme for the formation of these compounds. Although several key enzyme genes have been identified, the biosynthetic pathway of(+)-borneol, which has the most economic value, has not been reported. In this study, nine terpenoid synthase genes CcTPS1-CcTPS9 were cloned through transcriptome analysis of four chemical-type leaves. After the recombinant protein was induced by Escherichia coli, geranyl pyrophosphate(GPP) and farnesyl pyrophosphate(FPP) were used as substrates for enzymatic reaction, respectively. Both CcTPS1 and CcTPS9 could catalyze GPP to produce bornyl pyrophosphate, which could be hydrolyzed by phosphohydrolase to obtain(+)-borneol, and the product of(+)-borneol accounted for 0.4% and 89.3%, respectively. Both CcTPS3 and CcTPS6 could catalyze GPP to generate a single product linalool, and CcTPS6 could also react with FPP to generate nerolidol. CcTPS8 reacted with GPP to produce 1,8-cineol(30.71%). Nine terpene synthases produced 9 monoterpene and 6 sesquiterpenes. The study has identified the key enzyme genes responsible for borneol biosynthesis in C. camphora for the first time, laying a foundation for further elucidating the molecular mechanism of chemical type formation and cultivating new varieties of borneol with high yield by using bioengineering technology.
Cinnamomum camphora/enzymology* ; Alkyl and Aryl Transferases/chemistry*