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.

This study explores the mechanism of Guben Jiannao Liquid on Alzheimer's disease(AD) by regulating autophagy based on the liver kinase B1(LKB1)/adenosine monophosphate-activated protein kinase(AMPK)/mammalian target of rapamycin(mTOR) pathway. Male SD rats were randomly divided into the blank group, model group, low-dose and high-dose groups of Guben Jiannao Liquid, and rapamycin group, with 10 rats in each group. Except for the blank group, all other groups of rats were injected bilaterally in the hippocampus with β-amyloid(Aβ)_(1-42) to establish the AD model. The low-dose(6.21 g·kg~(-1)) and high-dose(12.42 g·kg~(-1)) groups of Guben Jiannao Liquid and rapamycin group(1 mg·kg~(-1)) were given the corresponding drugs by gavage, and the blank and model groups were given an equal volume of saline by gavage for four weeks. Morris water maze was used to test the learning and memory ability of rats in each group; hematoxylin-eosin(HE) and Nissl staining were used to observe the morphological and quantitative changes of neurons and Nissl bodies in the CA1 region of rat hippocampus; immunohistochemistry was utilized to detect Aβ-positive cell expression in the CA1 region of rat hippocampus; transmission electron microscopy was employed to observe ultrastructural changes in rat hippocampal tissue, and Western blot was used to examine the protein expression levels of LKB1, p-AMPK/AMPK, p-mTOR/mTOR, Beclin1, p62, and LC3-Ⅱ in the hippocampal tissue of the rats. The results showed that compared with those in the blank group, rats in the model group had elevated evasion latency and decreased number of platform transversal and residence time in the platform quadrant. The number of neurons in the hippocampal area was reduced, and the morphology was impaired. The average integral optical density value of Aβ-positive cells was elevated; the expression levels of LKB1, p-AMPK/AMPK, Beclin1, and LC3-Ⅱ were decreased, and the expression levels of p-mTOR/mTOR and p62 were increased. Compared with those in the model group, rats in the low-dose and high-dose groups of Guben Jiannao Liquid had shorter evasion latency, higher number of platform transversal, longer residence time in the platform quadrant, increased number of neurons, decreased expression of Aβ-positive cells and average integral optical density values, and increased number of autophagic lysosomes in hippocampal tissue. The expression levels of LKB1, Beclin1, and LC3-Ⅱ were elevated in the hippocampus of rats in the low-dose group of Guben Jiannao Liquid. The expression levels of LKB1, p-AMPK/AMPK, Beclin1, and LC3-Ⅱ were elevated in the hippocampal tissue of rats in the high-dose group of Guben Jiannao Liquid, and the expression levels of p-mTOR/mTOR and p62 were decreased. The findings suggest that Guben Jiannao Liquid can improve cognitive impairment in AD rats, and its mechanism of action may be related to the activation of the LKB1/AMPK/mTOR signaling pathway and the up-regulation of autophagy level.
Animals ; Alzheimer Disease/physiopathology* ; Male ; TOR Serine-Threonine Kinases/genetics* ; Autophagy/drug effects* ; Rats, Sprague-Dawley ; Protein Serine-Threonine Kinases/genetics* ; AMP-Activated Protein Kinases/genetics* ; Rats ; Drugs, Chinese Herbal/administration & dosage* ; Signal Transduction/drug effects* ; AMP-Activated Protein Kinase Kinases ; Humans ; Hippocampus/metabolism*

This study aims to investigate the effect of Congrong San(CRS) on endoplasmic reticulum stress-induced neuroinflammation in the rat model of Aβ_(1-42)-induced Alzheimer's disease(AD). Sixty male Sprague-Dawley rats(2 months old) were randomized into blank(CON), model(MOD), low-dose Congrong San(L-CRS), medium-dose Congrong San(M-CRS), high-dose Congrong San(H-CRS), and memantine hydrochloride(MJG) groups. The Morris water maze test was carried out to examine the learning and memory abilities of rats in each group. Hematoxylin-eosin staining and Nissl staining were employed to observe the morphology and number of CA1 neurons in the hippocampus of rats in each group. The morphology and structure of the endoplasmic reticulum in the hippocampus were observed by transmission electron microscopy. The immunofluorescence assay was employed to detect the expression of 78 kDa glucose-regulated protein(GRP78) in the hippocampus. Western blot was employed to determine the expression of apoptosis-associated speck-like protein containing a CARD(ASC), cysteinyl aspartate-specific proteinase(caspase-1), interleukin-18(IL-18), interleukin-1β(IL-1β), GRP78, and pathway proteins including protein kinase RNA-like endoplasmic reticulum kinase(PERK), phosphorylated PERK(p-PERK), C/EBP homologous protein(CHOP), and NOD-like receptor pyrin domain-containing protein 3(NLRP3) in the rat hippocampus. Compared with the MOD group, the M-CRS and H-CRS groups showed improved learning and memory abilities, reduced neuron losses in the hippocampus, alleviated endoplasmic reticulum stress, inhibited PERK-CHOP-NLRP3 pathway, and lowered levels of IL-1β, IL-6, and tumor necrosis factor-alpha(TNF-α). The results suggest that CRS can alleviate cognitive impairment and hippocampal neuron damage and reduce neuroinflammation in AD rats by alleviating endoplasmic reticulum stress to inhibit the activation of NLRP3 inflammasomes.
Animals ; Endoplasmic Reticulum Stress/drug effects* ; Male ; Alzheimer Disease/psychology* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Rats, Sprague-Dawley ; Rats ; Inflammasomes/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Cognitive Dysfunction/metabolism* ; Disease Models, Animal ; Hippocampus/drug effects* ; Humans ; Neuroinflammatory Diseases/drug therapy*

This study explores the effect and mechanism of Banxia Xiexin Decoction(BXD) in inhibiting colon cancer progression by reshaping tryptophan metabolism. Balb/c mice were assigned into control, model, low-dose BXD(BXD-L), and high-dose BXD(BXD-H) groups. Except the control group, the other groups were subcutaneously injected with CT26-Luc cells for the modeling of colon cancer, which was followed by the intervention with BXD. Small animal live imaging was employed to monitor tumor growth, and the tumor volume and weight were measured. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in mouse tumors. Immunohistochemistry was used to detect Ki67 expression in tumors. Immunofluorescence and flow cytometry were used to detect the infiltration and number changes of CD3~+/CD8~+ T cells in the tumor tissue. Enzyme-linked immunosorbent assay(ELISA) was employed to measure the levels of interferon-gamma(IFN-γ) and interleukin-2(IL-2) in tumors. Targeted metabolomics was employed to measure the level of tryptophan(Trp) in the serum, and the Trp content in the tumor tissue was measured. Western blot and RT-qPCR were employed to determine the protein and mRNA levels, respectively, of indoleamine 2,3-dioxygenase 1(IDO1), MYC proto-oncogene, and solute carrier family 7 member 5(SLC7A5) in the tumor tissue. Additionally, a co-culture model with CT26 cells and CD8~+ T cells was established in vitro and treated with the BXD-containing serum. The cell counting kit-8(CCK-8) assay was used to examine the viability of CT26 cells. The content of Trp in CT26 cells and CD8~+ T cells, as well as the secretion of IFN-γ and IL-2 by CD8~+ T cells, was measured. RT-qPCR was used to determine the mRNA levels of MYC and SLC7A5 in CT26 cells. The results showed that BXD significantly inhibited the tumor growth, reduced the tumor weight, and decreased the tumor volume in the model mice. In addition, the model mice showed sparse arrangement of tumor cells, varying degrees of patchy necrosis, and downregulated expression of Ki67 in the tumor tissue. BXD elevated the levels of IFN-γ and IL-2 in the tumor tissue, while upregulating the ratio of CD3~+/CD8~+ T cells and lowering the levels of Trp, IDO1, MYC, and SLC7A5. The co-culture experiment showed that BXD-containing serum reduced Trp uptake by CT26 cells, increased Trp content in CD8~+T cells, enhanced IL-2 and IFN-γ secretion of CD8~+T cells, and down-regulated the mRNA levels of MYC and SLC7A5 in CT26 cells. In summary, BXD can inhibit the MYC/SLC7A5 pathway to reshape Trp metabolism and adjust Trp uptake by CD8~+ T cells to enhance the cytotoxicity, thereby inhibiting the development of colon cancer.
Animals ; Tryptophan/metabolism* ; Colonic Neoplasms/pathology* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Mice, Inbred BALB C ; Humans ; Cell Line, Tumor ; Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism* ; Female ; Disease Progression ; Cell Proliferation/drug effects* ; Proto-Oncogene Mas ; Male

To explore the common irritant components in different base sources of Polygonati Rhizoma(PR). A rabbit eye irritation experiment was conducted to compare the irritant effects of raw products of Polygonatum kingianum, P. officinale, and P. multiflorum. The irritant effects of different solvent extraction parts and needle crystals of PR were compared, and the irritant components were screened. The morphology and structure of the purified needle crystal of PR were observed by microscope and scanning electron microscope and characterized by X-ray diffraction. Rabbit eye irritation and mouse abdominal inflammation model were used to evaluate rabbit eye irritation scores, inflammatory mediators, inflammatory factors levels in the peritoneal exudate of mice, with the peritoneal pathological section used as indicators. The inflammatory effect of needle crystals of PR was studied, and the content of calcium oxalate in three kinds of PR was determined by HPLC. The common protein in three kinds of PR was screened and compared by double enzymatic hydrolysis in solution combined with mass spectrometry. The results showed that three kinds of PR raw products had certain irritant effects on rabbit eyes, among which P. kingianum had the strongest irritant effect. There were no obvious irritant effects in the different solvent extraction parts of P. kingianum. Compared with the blank group, the needle crystal of PR had a significant irritant effect on rabbit eyes, and the inflammatory mediators and inflammatory factors in the peritoneal exudate were significantly increased(P<0.05) in a dose-dependent manner. Meanwhile, the peritoneal tissue of mice was damaged with significant inflammatory cell infiltration after intraperitoneal injection of needle crystal, indicating that needle crystal had an inflammatory effect. Microscope and scanning electron microscope observations showed that the needle crystals of PR were slender, with a length of about 100-200 μm and sharp ends. X-ray diffraction analysis showed that the needle crystals of PR were calcium oxalate monohydrate crystals. The results of HPLC showed that the content of calcium oxalate in P. kingianum was the highest among the three kinds of PR. It was speculated that the content of needle crystal in P. kingianum was higher than that in P. officinale and P. multiflorum, which was consistent with the results of the rabbit eye irritation experiment. The results of mass spectrometry showed that ribosome inactivating protein and mannose/sialic acid binding lectin were related to inflammation and cell metabolism in all three kinds of PR. There was no obvious irritant effect in different solvent extracts of PR. The calcium oxalate needle crystal contained was the main irritant component of PR, and three kinds of PR contained common ribosome inactivating protein and mannose/sialic acid binding lectin, which may be related to the inflammatory irritant effect of PR.
Animals ; Rabbits ; Mice ; Polygonatum/chemistry* ; Drugs, Chinese Herbal/toxicity* ; Rhizome/chemistry* ; Male ; Eye/drug effects* ; Female ; Humans

Glucocorticoid-induced osteoporosis(GIOP) is a serious metabolic bone disease caused by long-term application of glucocorticoids(GCs). Traditional Chinese medicine(TCM) has unique advantages in improving bone microstructure and antagonizing hormone toxicity. This paper systematically reviews the theoretical research, clinical application, and basic research progress of TCM intervention in GIOP. In terms of theoretical research, the theory of "kidney governing bone and generating marrow" indicates that the kidney is closely related to bone development, revealing that core pathogenesis of GIOP is Yin-Yang disharmony, which can be discussed using the theories of "Yin fire", "ministerial fire", and "Yang pathogen damaging Yin". Thus, regulating Yin and Yang is the basic principle to treat GIOP. In terms of clinical application, effective empirical prescriptions(such as Bushen Zhuanggu Decoction, Bushen Jiangu Decoction, and Zibu Ganshen Formula) and Chinese patent medicines(Gushukang Capsules, Hugu Capsules, Xianling Gubao Capsules, etc.) can effectively increase bone mineral density(BMD) and improve calcium and phosphorus metabolism. The combination of traditional Chinese and western medicine can reduce the risk of fracture and play an anti-GIOP role. In terms of basic research, it has been clarified that active ingredients of TCM(such as fraxetin, ginsenoside Rg_1, and salidroside) reduce bone loss and promote bone formation by inhibiting oxidative stress, ferroptosis, and other pathways, effectively improving bone homeostasis. Additionally, classical prescriptions(Modified Yiguan Decoction, Modified Qing'e Pills, Zuogui Pills, etc.) and Chinese patent medicines(Gushukang Granules, Lurong Jiangu Dropping Pills, Gubao Capsules, etc.) can improve bone marrow microcirculation, promote osteoblast differentiation, and inhibit bone cell apoptosis through multiple pathways, multiple targets, and multiple mechanisms. Through the above three aspects, the TCM research status on GIOP is elucidated in the expectation of providing reference for its diagnosis and treatment using traditional Chinese and western medicine treatment programs.
Osteoporosis/physiopathology* ; Humans ; Glucocorticoids/adverse effects* ; Drugs, Chinese Herbal/administration & dosage* ; Animals ; Medicine, Chinese Traditional ; Bone Density/drug effects*

From the perspective of circular RNA forkhead box protein O3(circFOXO3) regulating glycolysis in osteoarthritis(OA) chondrocytes, this study investigated the mechanism by which Tougu Xiaotong Capsules(TGXTC) alleviated OA degeneration. In in vivo experiments, after randomized grouping and relevant interventions, morphological staining was used to observe structural changes in cartilage tissue. The mRNA level of circFOXO3 in cartilage tissue was detected by real-time quantitative PCR(RT-qPCR). Western blot analysis was used to detect changes in the expression of glucose transporter 1(GLUT1), hexokinase 2(HK2), pyruvate kinase M2(PKM2), lactate dehydrogenase A(LDHA), and matrix metalloproteinase 13(MMP13). In in vitro experiments, fluorescence in situ hybridization(FISH) was used to detect circFOXO3 expression in chondrocytes from each group. A lentiviral vector was used to construct circFOXO3-silenced(sh-circFOXO3) chondrocytes. RT-qPCR was used to analyze the changes in circFOXO3 levels after silencing, and Western blot was used to assess the regulatory effects of TGXTC on GLUT1, HK2, PKM2, LDHA, and MMP13 proteins in interleukin-1β(IL-1β)-induced chondrocytes under sh-circFOXO3 conditions. Masson staining and alcian blue staining results showed that the cartilage layer structure in the TGXTC and positive drug groups was improved compared with that in the model group. The mRNA level of circFOXO3 was significantly upregulated in both the TGXTC and positive drug groups, while the expression of the above-mentioned proteins was significantly reduced. FISH results showed that TGXTC upregulated the fluorescence intensity of circFOXO3 in IL-1β-induced chondrocytes. In the circFOXO3 silencing experiment, compared with the IL-1β group, circFOXO3 levels in the IL-1β + sh-circFOXO3 group were significantly decreased. Compared with the IL-1β + TGXTC group, circFOXO3 levels were significantly reduced in the IL-1β + sh-circFOXO3 + TGXTC group. Western blot results indicated that the elevated levels of GLUT1, HK2, PKM2, LDHA, and MMP13 proteins in chondrocytes of the IL-1β group were significantly inhibited by TGXTC intervention. However, this regulatory effect was attenuated after circFOXO3 silencing. In conclusion, TGXTC alleviate glycolytic metabolism disorder in OA chondrocytes and delay OA degeneration by regulating circFOXO3.
Chondrocytes/metabolism* ; Animals ; Drugs, Chinese Herbal/administration & dosage* ; RNA, Circular/metabolism* ; Osteoarthritis/genetics* ; Glycolysis/drug effects* ; Humans ; Forkhead Box Protein O3/metabolism* ; Male ; Capsules ; Matrix Metalloproteinase 13/genetics*

This study investigated the therapeutic effects of Yiguanjian on dry eye in rats and its mechanisms involving the T helper cell 17(Th17)/regulatory T cell(Treg) balance. The rat model of dry eye was established by administrating 0.2% benzalkonium chloride solution in eye drops. After successful modeling, the rats were treated with Yiguanjian for 4 consecutive weeks. The Schirmer test was carried out to assess the lacrimal gland function, corneal fluorescence staining to detect corneal injury, hematoxylin-eosin staining to observe corneal histopathology, enzyme-linked immunosorbent assay to measure serum levels of interleukin(IL)-6, IL-8, IL-17A, IL-21, and tumor necrosis factor-α(TNF-α), RT-qPCR to analyze mRNA levels of retinoic acid receptor-related orphan receptor gamma t(RORγt) and forkhead box protein p3(Foxp3) in the corneal tissue, immunofluorescence double staining to evaluate RORγt and Foxp3 expression in the lacrimal gland tissue, and Western blot to quantify the protein levels of signal transducer and activator of transcription 3(STAT3), phosphorylated STAT3(p-STAT3), Janus kinase 2(Jak2), phosphorylated Jak2(p-Jak2), RORγt, and Foxp3 in the corneal tissue. The results demonstrated that Yiguanjian increased tear secretion(P<0.01), alleviated corneal damage and pathological changes, and lowered the serum levels of IL-6, IL-8, IL-17A, IL-21, and TNF-α(P<0.05) in model rats. Additionally, Yiguanjian decreased the ratio of RORγt to Foxp3 in the corneal and lacrimal gland tissue(P<0.01), downregulated the protein levels of STAT3, Jak2, and RORγt(P<0.05), upregulated the protein level of Foxp3(P<0.05), and inhibited phosphorylation of STAT3 and Jak2(P<0.01). These findings indicate that Yiguanjian ameliorates ocular surface dysfunction in dry eye rats by restoring Th17/Treg balance in the corneal and lacrimal gland tissue and suppressing systemic inflammatory cytokine release, thus mitigating ocular surface inflammation.
Animals ; Rats ; T-Lymphocytes, Regulatory/immunology* ; Drugs, Chinese Herbal/administration & dosage* ; Th17 Cells/immunology* ; Male ; Rats, Sprague-Dawley ; Dry Eye Syndromes/genetics* ; Nuclear Receptor Subfamily 1, Group F, Member 3/immunology* ; Lacrimal Apparatus/immunology* ; Humans ; STAT3 Transcription Factor/immunology*

OBJECTIVE: To explore the mechanism by which the extract of Semen Ziziphi Spinosae extract promotes bone growth in mice by modulation of the expression of miR-34a-5p in brain tissue. METHODS: Mice were assigned to four experimental groups:a normal control group, a drug administration group (receiving 0.320 mg·g^-1 body weight of Semen Ziziphi Spinosae extract via intragastric administration), a positive control group (receiving 0.013 mg·g^-1 body weight of jujube seed saponin via intragastric administration), and a combination group administration with Semen Ziziphi Spinosae extract plus a 5-hydroxytryptamine 2A receptor (5-HT2AR) agonist (intragastric administration of Semen Ziziphi Spinosae extract combined with intracerebroventricular injection of 8 μg P-MPPF per mice for the final three days of the experiment). Following a 20-day administration period, the effects of the interventions on bone growth, serum growth hormone (GH) levels, and 5-HT2AR expression in brain tissue were evaluated. MicroRNAs (miRNAs) that were differentially expressed in the brain tissues of mice exhibiting bone growth induced by Semen Ziziphi Spinosae extract, as compared to those in normal mice, were identified using a gene chip approach. The interaction between miR-34a-5p and 5-HT2AR was subsequently validated through quantitative reverse transcription polymerase chainreaction (RT-qPCR) and dual-luciferase reporter gene assays. Subsequently, by utilizing the miR-34a-5p inhibitor group and mimics group, along with the normal control group, the drug administration group, the positive control group, and the drug administration combined with miR-34a-5p inhibitor group, the variations in 5-HT2AR expression in mouse brain tissue across all groups were examined, and the binding activity of 5-hydroxytryptamine (5-HT) to the 5-hydroxytryptamine 1A receptor (5-HT1AR) in mice was assessed. RESULTS: The body lengths of the normal control group and the drug administration group were(8.9±0.3) and(10.4±0.4) cm;femur lengths were (8.5±0.3) and (9.1±0.5) mm;tibia lengths were (10.7±0.3) and (11.2±0.4) mm, respectively. The contents of GH levels were (58.6±8.2) and (72.9±6.1) ng·ml-1;and the contents of 5-HT2AR were (32.0±5.0) and (21.9± 5.5) ng·ml-1, respectively. Compared with the normal control group, the drug administration group promoted the growth of body length, femur, and tibia in mice, and increased GH secretion, showing statistically significant differences (P<0.05). Additionally, it significantly reduced the content of 5-HT2AR in brain tissue, with statistical significance (P<0.01). The gene chip analysis identified a total of 16 differentially expressed miRNAs, of which 13 were up-regulated and 3 were down-regulated. Bioinformatics analysis predicted that the up-regulated miR-34a-5p could regulate the expression of 5-HT2AR, a prediction that was confirmed through a dual-luciferase reporter gene assay, demonstrating a direct regulatory interaction between the two. Furthermore, in vivo experiments in mice revealed that overexpression and silencing of miR-34a-5p resulted in corresponding changes in the expression levels of 5-HT2AR in brain tissues/cells, as well as in the binding activity between 5-HT and 5-HT1AR. CONCLUSION The Semen Ziziphi Spinosae extract promotes animal bone growth by enhancing miR-34a-5p expression in brain tissue, downregulating the expression level of 5-HT2AR, improving the binding activity between 5-HT and 5-HT1AR, and extending slow-wave sleep duration, thereby stimulating GH secretion.
Animals ; MicroRNAs/metabolism* ; Mice ; Male ; Brain/metabolism* ; Ziziphus/chemistry* ; Bone Development/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Plant Extracts/pharmacology*