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.

This study aimed to investigate the effect of saltwater stir-fried Plantaginis Semen(SPS) on renal fibrosis in rats and decipher the underlying mechanism. Thirty-six Sprague-Dawley rats were randomly assigned into control, model, losartan potassium, and low-, medium-, and high-dose(15, 30, and 60 g·kg~(-1), respectively) SPS groups. Rats in other groups except the control group were subjected to unilateral ureteral obstruction(UUO) to induce renal fibrosis, and the modeling and gavage lasted for 14 days. After 14 consecutive days of treatment, the levels of serum creatinine(Scr) and blood urea nitrogen(BUN) in rats of each group were determined by an automatic biochemical analyzer. Hematoxylin-eosin(HE) and Masson staining were used to evaluate pathological changes in the renal tissue. Western blot and immunofluorescence assay were conducted to determine the protein levels of fibronectin(FN), collagen Ⅰ, vimentin, and α-smooth muscle actin(α-SMA) in the renal tissue. The mRNA levels of epithelial-mesenchymal transition(EMT)-associated transcription factors including twist family bHLH transcription factor 1(TWIST1), snail family transcriptional repressor 1(SNAI1), and zinc finger E-box binding homeobox 1(ZEB1), as well as inflammatory cytokines such as interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α), were determined by RT-qPCR. Human renal proximal tubular epithelial(HK2) cells exposed to transforming growth factor-β(TGF-β) for the modeling of renal fibrosis were used to investigate the inhibitory effect of SPS on EMT. Network pharmacology and Western blot were employed to explore the molecular mechanism of SPS in alleviating renal fibrosis. The results showed that SPS significantly reduced Scr and BUN levels and alleviated renal injury and collagen deposition in UUO rats. Moreover, SPS notably down-regulated the protein levels of FN, collagen Ⅰ, vimentin, and α-SMA as well as the mRNA levels of SNAI1, ZEB1, TWIST1, IL-1β, IL-6, and TNF-α in the kidneys of UUO rats and TGF-β-treated HK-2 cells. In addition, compared with Plantaginis Semen without stir-frying with saltwater, SPS showed increased content of specific compounds, which were mainly enriched in the mitogen-activated protein kinase(MAPK) signaling pathway. SPS significantly inhibited the phosphorylation of extracellular signal-regulated kinase(ERK) and p38 MAPK in the kidneys of UUO rats and TGF-β-treated HK2 cells. In conclusion, SPS can alleviate renal fibrosis by attenuating EMT through inhibition of the MAPK signaling pathway.
Animals ; Epithelial-Mesenchymal Transition/drug effects* ; Rats, Sprague-Dawley ; Male ; Rats ; Fibrosis/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Kidney Diseases/pathology* ; Kidney Tubules/pathology* ; Humans

This study compared the differences in intestinal absorption characteristics of eleven active components in Rubus multibracteatus(RM) extract(protocatechuic acid, tiliroside, scutellarin, luteoloside, astragalin, epicatechin, catechin, xanthotoxin, p-coumaric acid, caffeic acid, and apigenin-7-O-glucuronide) between normal rats and inflammatory pain model rats using the in-vitro everted intestinal sac model. The RM extract was administered at absorption concentrations of 25.0, 50.0, and 100.0 mg·mL~(-1). The contents of the eleven components in intestinal absorption solution samples were quantified by ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS), and their cumulative absorption(Q) and absorption rate constant(K_a) were calculated to evaluate the absorption characteristics of these components in normal rats and inflammatory pain model rats. The results show that except for catechin, epicatechin, and caffeic acid, the cumulative absorption-time curves of the other eight components(protocatechuic acid, tiliroside, scutellarin, luteoloside, astragalin, xanthotoxin, p-coumaric acid, and apigenin-7-O-glucuronide) exhibit an upward trend without saturation, with correlation coefficients(R~2) all > 0.9, indicating linear absorption. However, the overall absorption of all components is not dose-dependent with increasing concentration, suggesting that their absorption mechanisms are not solely passive diffusion. In both normal and model rats, the jejunum shows the highest absorption for all components except xanthotoxin. The overall absorption of seven components(excluding protocatechuic acid, caffeic acid, apigenin-7-O-glucuronide, and luteoloside) in normal rats is better than that in model rats across all intestinal segments. These findings indicate that the pathological state of inflammatory pain alters the intestinal absorption of RM extract, and its mechanism needs further investigation.
Animals ; Rats ; Intestinal Absorption/drug effects* ; Male ; Rats, Sprague-Dawley ; Drugs, Chinese Herbal/metabolism* ; Disease Models, Animal ; Pain/metabolism* ; Intestines/drug effects* ; Intestinal Mucosa/metabolism*

Glaucoma is the leading cause of irreversible blindness worldwide, with its primary risk factor arising from elevated intraocular pressure (IOP) due to an imbalance between aqueous humor production and outflow. This study aims to establish quantitative correlations among IOP, iris mechanical properties, channel microstructures, and aqueous humor dynamics through three-dimensional modeling and finite element analysis, overcoming the limitations of conventional experimental techniques in studying aqueous flow within the trabecular meshwork (TM) outflow pathway. A three-dimensional fluid-structure interaction (FSI) model incorporating the layered TM structure, Schlemm's canal (SC), iris, and other anterior segment tissues was developed based on human ocular anatomy. FSI simulations were performed to quantify the effects of IOP variations and iris Young's modulus on tissue morphology and aqueous humor dynamics parameters. The computational results demonstrated that axial iris deformation showed significant correlations with IOP and iris Young's modulus. Although elevated IOP exhibited minimal effects on hydrodynamic parameters in the anterior and posterior chambers, it markedly suppressed aqueous flow velocity in the TM region. Additionally, wall shear stress in SC and collector channels displayed high sensitivity to IOP variations. These findings reveal that the tissue mechanics-FSI mechanism modulates outflow resistance by regulating aqueous humor dynamics, offering valuable references for developing clinical therapies targeting IOP reduction in glaucoma management.
Humans ; Trabecular Meshwork/anatomy & histology* ; Finite Element Analysis ; Aqueous Humor/metabolism* ; Intraocular Pressure/physiology* ; Glaucoma/physiopathology* ; Iris/anatomy & histology* ; Computer Simulation ; Models, Biological

Humans ; PPAR gamma/metabolism* ; Multiple Sclerosis ; Transcription Factors/metabolism* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha