Intermittent fasting and Alzheimer's disease-Targeting ketone bodies as a potential strategy for brain energy rescue.

Alzheimer's disease (AD) lacks effective clinical treatments. As the disease progresses, the cerebral glucose hypometabolism that appears in the preclinical phase of AD gradually worsens, leading to increasingly severe brain energy disorders. This review analyzes the brain energy deficit in AD and its etiology, brain energy rescue strategies based on ketone intervention, the effects and mechanisms of IF, the differences in efficacy between IF and ketogenic diet and the duality of IF. The evidence suggests that brain energy deficits lead to the development and progression of AD pathology. IF, which improves brain energy impairments by promoting ketone metabolism, thus has good therapeutic potential for AD.

[Research advances of prostaglandin E2 receptor 1 (EP1)].

Prostaglandin E2 (PGE2) is an important lipid molecule derived from arachidonic acid, which regulates a variety of physiological and pathological activities. Based on the inhibition of inflammatory PGE2 production, non-steroidal anti-inflammatory drugs (NSAIDs) are considered as the most commonly used drugs to treat inflammatory diseases and to relieve fever and pain symptoms. PGE2 mediates its functions via four different G protein-coupled receptors, named EP1-EP4. Though the limited distribution and low PGE2 affinity of EP1, it plays important roles in the maintenance of many physiological functions and homeostasis. Moreover, EP1 is widely involved in the inflammatory response, pain perception and multisystem pathological function regulation. In this review, we will briefly summarize the recent advances on the physiological and pathophysiological function of EP1 and its targeted drugs development.

Functional study of the soybean stamen-preferentially expressed gene GmFLA22a in regulating male fertility.

China has a high dependence on soybean imports, yield increase at a faster rate is an urgent problem that need to be solved at present. The application of heterosis is one of the effective ways to significantly increase crop yield. In recent years, the development of an intelligent male sterility system based on recessive nuclear sterile genes has provided a potential solution for rapidly harnessing the heterosis in soybean. However, research on male sterility genes in soybean has been lagged behind. Based on transcriptome data of soybean floral organs in our research group, a soybean stamen-preferentially expressed gene GmFLA22a was identified. It encodes a fasciclin-like arabinogalactan protein with the FAS1 domain, and subcellular localization studies revealed that it may play roles in the endoplasmic reticulum. Take advantage of the gene editing technology, the Gmfla22a mutant was generated in this study. However, there was a significant reduction in the seed-setting rate in the mutant plants at the reproductive growth stage. The pollen viability and germination rate of Gmfla22a mutant plants showed no apparent abnormalities. Histological staining demonstrated that the release of pollen grains in the mutant plants was delayed and incomplete, which may due to the locule wall thickening in the anther development. This could be the reason of the reduced seed-setting rate in Gmfla22a mutants. In summary, our study has preliminarily revealed that GmFLA22a may be involved in regulating soybean male fertility. It provides crucial genetic materials for further uncovering its molecular function and gene resources and theoretical basis for the utilization of heterosis in soybean.

COLEC10 Induces Endoplasmic Reticulum Stress by Occupying GRP78 and Inhibits Hepatocellular Carcinoma.

Collectin subfamily member 10 (COLEC10), a C-type lectin mainly expressed in the liver, is involved in the development of hepatocellular carcinoma (HCC). However, its underlying molecular mechanism in HCC progression remains unknown. In this study, reduced COLEC10 expression in tumor tissues was validated using various HCC cohorts and was associated with poor patient prognosis. COLEC10 overexpression attenuated HCC cell growth and migration abilities in vitro and in vivo. We identified that COLEC10 was a novel interactor of 78-kDa glucose-regulated protein (GRP78), a master modulator of the unfolded protein response in the endoplasmic reticulum (ER). COLEC10 overexpression potentiated ER stress in HCC cells, as demonstrated by elevated expression levels of phosphorylated protein kinase RNA-like ER kinase, phosphorylated inositol-requiring protein 1α, activating transcription factor 4, DNA damage-inducible transcript 3, and X-box-binding protein 1s. The ER in COLEC10-overexpressing cells also showed a dilated and fragmented pattern. Mechanistically, COLEC10 overexpression increases GRP78 occupancy through direct binding by the C-terminal carbohydrate recognition domain in the ER, which released and activated the ER stress transducers protein kinase RNA-like ER kinase and phosphorylated inositol-requiring protein 1α, triggering the unfolded protein response activity. COLEC10-overexpressing HCC cells generated a relatively high reactive oxygen species level and switched to apoptotic cell death under sorafenib-treated conditions. Our study provides the first novel view that COLEC10 inhibits HCC progression by regulating GRP78-mediated ER stress signaling and may serve as a promising therapeutic and prognostic biomarker.

MBL2 polymorphism may be a protective factor of autoimmune thyroid disease susceptibility.

Genetic susceptibility is an essential pathogenetic mechanism in autoimmune thyroid disease (AITD). MBL2 gene polymorphisms have been shown to play a vital role in the pathogenesis of multiple autoimmune disorders, but its contribution to AITD is unclear. The aim of this study was to assess the linkage between MBL2 gene polymorphisms and AITD susceptibility in a Chinese Han population. One thousand seven hundred sixty seven subjects consisting of 965 AITD patients and 802 controls from a Chinese Han population were enrolled in the case-control study. Four common single-nucleotide polymorphisms (SNPs) in the MBL2 gene were tested using high-throughput sequencing technology for sequence-based SNP genotyping. The allele and genotype distribution results showed that the minor alleles of rs198266, rs10824793, and rs4935046 were significantly lower in Hashimoto's thyroiditis (HT) patients than in healthy controls. In further genetic model analysis, the dominant models of rs1982266, rs10824793, and rs4935046 for MBL2 in the AITD group exhibited a lower risk of morbidity. Finally, we discovered that haplotype AAGC was associated with Graves' disease (GD), while AGC was associated with HT. Our study provides strong evidence for a genetic correlation between MBL2 and AITD, and the polymorphism of the MBL2 gene may be a protective factor for AITD, especially for HT. These findings can advance our understanding of the etiology of AITD, as well as provide guidance for prevention and intervention toward AITD.

[Recent studies on dilated cardiomyopathy caused by TTN mutations in children]. / TTNåŸºå› çªå˜è‡´å„¿ç«¥æ‰©å¼ åž‹å¿ƒè‚Œç— çš„ç ”ç©¶è¿›å±•.

The mutations of TTN gene that encodes titin are the most common mutation type among the genetic causes of dilated cardiomyopathy (DCM). This article reviews the worldwide studies on potential molecular pathogenesis (transcription, post-translational modification, etc.), clinical phenotypes, and gene therapies of pediatric DCM caused by TTN mutations, with the hope of providing a reference for the precision treatment of pediatric DCM caused by TTN mutations.

[Clinical and genetic characteristics of children with primary dilated cardiomyopathy]. / å„¿ç«¥åŽŸå‘æ€§æ‰©å¼ åž‹å¿ƒè‚Œç— çš„ä¸´åºŠç‰¹å¾åŠé—ä¼ å­¦åˆ†æž.

OBJECTIVES: To study the genetic characteristics, clinical characteristics, and prognosis of children with primary dilated cardiomyopathy (DCM). METHODS: A retrospective analysis was performed on the medical data of 44 children who were diagnosed with DCM in Hebei Children's Hospital from July 2018 to February 2023. According to the genetic testing results, they were divided into two groups: gene mutation-positive group (n=17) and gene mutation-negative group (n=27). The two groups were compared in terms of clinical data at initial diagnosis and follow-up data. RESULTS: Among the 44 children with DCM, there were 21 boys (48%) and 23 girls (52%). Respiratory symptoms including cough and shortness of breath were the most common symptom at initial diagnosis (34%, 15/44). The detection rate of gene mutations was 39% (17/44). There were no significant differences between the two groups in clinical characteristics, proportion of children with cardiac function grade Ⅲ or Ⅳ, brain natriuretic peptide levels, left ventricular ejection fraction, and left ventricular fractional shortening at initial diagnosis (P>0.05). The median follow-up time was 23 months, and 9 children (20%) died, including 8 children from the gene mutation-positive group, among whom 3 had TTN gene mutation, 2 had LMNA gene mutation, 2 had TAZ gene mutation, and 1 had ATAD3A gene mutation. The gene mutation-positive group had a significantly higher mortality rate than the gene mutation-negative group (P<0.05). CONCLUSIONS: There is no correlation between the severity of DCM at initial diagnosis and gene mutations in children. However, children with gene mutations may have a poorer prognosis.

Decreased Methylenetetrahydrofolate Reductase Activity Leads to Increased Sensitivity to para-Aminosalicylic Acid in Mycobacterium tuberculosis.

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is one of the most fatal diseases in the world. Methylenetetrahydrofolate reductase (MTHFR) catalyzes the production of 5-methyltetrahydrofolate (5-CH3-THF), which is required for the de novo biosynthesis of methionine in bacteria. Here, we identified Rv2172c as an MTHFR in M. tuberculosis through in vitro and in vivo analyses and determined that the protein is essential for the in vitro growth of the bacterium. Subsequently, we constructed rv2172c R159N and L214A mutants in M. tuberculosis and found that these mutants were more sensitive to the antifolates para-aminosalicylic acid (PAS) and sulfamethoxazole (SMX). Combining biochemical and genetic methods, we found that rv2172c R159N or L214A mutation impaired methionine production, leading to increased susceptibility of M. tuberculosis to PAS, which was largely restored by adding exogenous methionine. Moreover, overexpression of rv2172c in M. tuberculosis could increase methionine production and lead to PAS resistance. This research is the first to identify an MTHFR in M. tuberculosis and reveals that the activity of this enzyme is associated with susceptibility to antifolates. These findings have particular value for antitubercular drug design for the treatment of drug-resistant TB.

Target identification of anti-diabetic and anti-obesity flavonoid derivative (Fla-CN).

Fla-CN is a flavonoid derivative with anti-diabetic and anti-obesity effects; however, its biological targets are still unknown. In this study, we developed bifunctional affinity-based probes to identify the direct targets of Fla-CN. When using probe 3, we observed the co-location of probe 3 and mitochondria in both HepG2 and 3T3-L1 cells. The putative target proteomes were obtained using activity-based protein profiling (ABPP) and photo-affinity labelling. Pyruvate carboxylase, mitochondrial malate dehydrogenase, mitochondrial complex I, and F1FO-ATPase were validated as the direct targets of Fla-CN by surface plasmon resonance (SPR) and biochemical assays. It was elucidated that the Tyr651, Gln870 and Lys912 were the key amino acid residues near the binding site of pyruvate carboxylase with Fla-CN. The direct interaction of Fla-CN and the above four targets allowed elucidation of its complicated molecular mechanism, including the activation of adenosine 5-monophosphate (AMP)-activated protein kinase (AMPK), and the inhibition of gluconeogenesis. Further investigation for activation of AMPK in normal and insulin resistance (IR) HepG2 cells, indicated that Fla-CN could target insulin resistance tissues.

Comparison of predictive value of risk scores for gastrointestinal bleeding in antiplatelet therapy.

Gastrointestinal bleeding (GIB) is the most common serious bleeding complication of antiplatelet therapy. The bleeding risk score (BRS) of GIB may help to determine the risk of bleeding, and provides a reference for the formulation of antiplatelet therapy regimen in clinical practice, but we found that no specific risk scores are available in East Asian patients. This study analyzed patients who were administered antiplatelet therapy from May 2015 to December 2018 in two medical centers. Patient's baseline data were obtained. We assessed four BRSs (New Score, RIETE Score, Cuschieri Score, de Groot Score) and compared them using the area under the receiver operating characteristic curve (AUC). The 4,052 patients enrolled in this study had an average age of 69.6 ± 10.8 years, and 65.9% of them were male. Among the 4,052 patients included, 171 patients experienced GIB within 6 months of follow-up. In the study population, the AUCs for the New, RIETE, Cuschieri, and de Groot scores were 0.673 (95% confidence interval (CI) 0.616-0.729, P < .001), 0.742 (95% CI 0.690-0.794, P < .001), 0.598 (95% CI 0.537-0.659, P = .002), and 0.875 (95% CI 0.839-0.912, P < .001), respectively. After validation, the de Groot Score has better performance. Among the four scores, the de Groot Score might be more suitable for helping Chinese clinicians to predict the risk of GIB in patients taking antiplatelet drugs, and reduce GIB events.

Comparison of clinical performance of four gastrointestinal bleeding risk scores in Chinese patients with atrial fibrillation receiving oral anticoagulants.

Gastrointestinal bleeding is the most common bleeding complication during anticoagulant therapy. A reliable bleeding risk score can help the clinician assess risk of bleeding in individual patients and select the anticoagulant regimen. This study retrospectively analyzed the data of patients with atrial fibrillation who received anticoagulant therapy from July 2015 to December 2018 at two centers-the Fujian Medical University Union Hospital and Fuzhou Second Hospital Affiliated to Xiamen University. Demographic data, clinical findings, and laboratory results were collected from the hospital records. Patients were followed up for 6 months. The performance of four bleeding risk scores (New Score, RIETE Score, Cuschieri et al. Score, de Groot et al. Score) for prediction of gastrointestinal bleeding was assessed using the area under the curve. A total of 3462 patients (mean age, 66.3 ± 11.5 years; 59.6% males; 1055 direct oral anticoagulants users and 2407 warfarin users) were followed up for 6 months. While 99/3462 (2.9%) patients had gastrointestinal bleeding. The area under the curves for the New, RIETE, Cuschieri et al., de Groot et al. scores were 0.652 (95% CI 0.576-0.728), 0.862 (95% CI 0.809-0.914), 0.606 (95% CI 0.527-0.685), and 0.873 (95% CI 0.816-0.929), respectively. Among the four BRSs evaluated, the RIETE score and the de Groot et al. score appear to have the good predictive value, while the NEW score and the Cuschieri et al. score did not sufficiently predict gastrointestinal bleeding risk within the study Chinese population.

Two new dibenzyl derivatives from the stems of Dendrobium catenatum.

Two new dibenzyl derivatives, dendrocandins V-W (1-2), together with six known compounds (3-8), have been isolated from the dried stems of Dendrobium catenatum. Their structures were mainly elucidated on the basis of HRESIMS, one- and two-dimensional NMR techniques. The isolated compounds 5-8 were evaluated in vitro for their antioxidant and hypoglycemic activities. Compound 8 showed moderate potent DPPH scavenging activity with IC50 value of 34.45 ± 1.07 µM. And compounds 5, 7-8 exhibited significant ABTS radical scavenging activities with IC50 values of 10.03 ± 0.88, 5.32 ± 1.13 and 9.01 ± 1.39 µM. Compounds 6-7 showed potent α-glucosidase inhibitory activities with IC50 values of 36.05 ± 0.67 and 159.59 ± 0.86 µM.

[Research advances of prostaglandin E2 synthases and receptors in cardiovascular diseases].

Prostaglandin E2 (PGE2) is an important lipid mediator derived from arachidonic acid. It is widely distributed in various tissues and involved in numerous physiological and pathophysiological processes. Based on the inhibition of inflammatory PGE2 production, non-steroidal anti-inflammatory drugs (NSAIDs) are considered as the most commonly used drugs to treat pain and inflammation. However, clinical trials have revealed that NSAIDs, especially cyclooxygenase-2 (COX-2) selective inhibitors, may predispose patients to a remarkably increased cardiovascular risk, including hypertension, myocardial infarction, and heart failure. This promotes scientists to develop new drugs to not only afford pain relief but also have cardiovascular efficacy. Microsomal prostaglandin E synthase-1 (mPGES-1), the key terminal enzyme catalyzing the synthesis of inflammatory PGE2, and the four PGE2 receptors (EP1-4) have gained more attention as the promising alternative drug targets for the development of novel NSAIDs. The role of mPGES-1 and EP receptors in cardiovascular diseases also has been widely studied. In this review, we highlight the most recent advances from our and other studies on the role of PGE2, particularly mPGES-1 and the four PGE2 receptors, in cardiovascular diseases.

[Chronic sleep deprivation exacerbates cognitive and pathological impairments in APP/PS1/tau triple transgenic Alzheimer's disease model mice].

Sleep exerts important functions in the regulation of cognition and emotion. Recent studies have found that sleep disorder is one of the important risk factors for Alzheimer's disease (AD), but the effects of chronic sleep deprivation on the cognitive functions of AD model mice and its possible mechanism are still unclear. In the present study, 8-month-old male APP/PS1/tau triple transgenic AD model (3xTg-AD) mice and wild type (WT) mice (n = 8 for each group) were subjected to chronic sleep deprivation by using the modified multiple platform method, with 20 h of sleep deprivation each day for 21 days. Then, open field test, elevated plus maze test, sugar water preference test, object recognition test, Y maze test and conditioned fear memory test were performed to evaluate anxiety- and depression-like behaviors, and multiple cognitive functions. In addition, the immunohistochemistry technique was used to observe pathological characteristics in the hippocampus of mice. The results showed that: (1) Chronic sleep deprivation did not affect anxiety- (P = 0.539) and depression-like behaviors (P = 0.874) in 3xTg-AD mice; (2) Chronic sleep deprivation exacerbated the impairments of object recognition memory (P < 0.001), working memory (P = 0.002) and the conditioned fear memory (P = 0.039) in 3xTg-AD mice; (3) Chronic sleep deprivation increased amyloid ß (Aß) deposition (P < 0.001) and microglial activation (P < 0.001) in the hippocampus of 3xTg-AD mice, without inducing abnormal tau phosphorylation and neurofibrillary tangles. These results indicate that chronic sleep deprivation exacerbates the impairments of recognition memory, working memory and conditioned fear memory in 3xTg-AD mice by aggravating Aß deposition and the excessive activation of microglia in the hippocampus.

Progress on genic male sterility gene in soybean.

Male sterility refers to the phenomenon that stamens cannot grow normally and produce viable pollen grains in plants. Hybrid seed production by taking advantage of the trait of male sterility is an effective and quick strategy to increase crop yield. Up to date, the yield of rice (Oryza sativa L.), maize (Zea mays L.), wheat (Triticum aestivum L.) and other crops has been greatly increased based on hybrid vigor utilization. Soybean (Glycine max (L.) Merr.) is a self-pollination species, artificial emasculation is not only time-consuming, but also labor-intensive and economically impracticable. So far, large scale hybrid breeding has not been performed in soybean due to the shortage of male sterile lines suitable for hybrid production. Therefore, it is urgent to identify a stable male sterile system for the rapid utilization of heterosis in soybean. In this review, we summarize the progress on the discovery of soybean genic male sterility (GMS) mutants and GMS genes. Combining with the investigation of GMS genes in Arabidopsis, rice and maize, we provide important insights into the identification and potential utilization of GMS genes in soybean in the perspective of reverse genetics.

Inhibition of expression of glucocorticoids receptors may contribute to postpartum depression.

Although postpartum depression (PPD) is the leading cause of disability worldwide, its molecular mechanisms are poorly understood. Recent evidence has suggested that impaired glucocorticoid receptor (GR), the signaling of key molecules of the HPA axis, plays a key role in the behavioral and neuroendorcrine alterations of major depression. However, the role of GR in postpartum period, which following with the abrupt withdrawal of placental corticotropin releasing hormone (CRH) and resulting in a re-equilibration of the maternal HPA axis in the days of post-delivery, is still not entirely clear. Previously, a hormone-simulated pregnancy (HSP), and the subsequent 'postpartum' withdrawal in estrogen has been employed to mimic the fluctuations in estradiol associated with pregnancy and postpartum. Using the HSP model, we investigated here the effect of 'postpartum' withdrawal in estrogen as well as depression- and anxiety-like behavior by intra-hippocampal infusion with GR inhibitor-RU486. Following the successful acquisition of PPD model by withdrawal in estrogen, reduced GR expression was observed in hippocampus. Further, HSP-rats suffered intra-hippocampal RU486 infusion presented depression- and anxiety-like behavior as postpartum depression. Together, these results suggest an important, though complex, role for GR in the behavioral regulation of postpartum depression.

PGC-1α regulate critical period plasticity via gene × environment interaction in the developmental trajectory to schizophrenia.

Genes and environmental conditions are thought to interact in the development of postnatal brain in schizophrenia (SZ). Genome wide association studies have identified that PPARGC1A being one of the top candidate genes for SZ. We previously reported GABAergic neuron-specific PGC-1α knockout mice (Dlx5/6-Cre:PGC-1αfl/fl) presented some characteristic features of SZ. However, there is a fundamental gap of the molecular mechanism by which PGC-1α gene involved in the developmental trajectory to SZ. To explore whether PGC-1α regulates environmental factors interacting with genetic susceptibility to trigger symptom onset and disease progression, PGC-1α deficient mice were utilized to model genetic effect and an additional oxidative stress was induced by GBR injection. We confirm that PGC-1α gene deletion prolongs critical period (CP) timing, as revealed by delaying maturation of PV interneurons (PVIs), including their perineuronal nets (PNNs). Further, we confirm that gene × environment (G × E) influences CP plasticity synergistically and the interaction varies as a function of age, with the most sensitive period being at preweaning stage, and the least sensitive one at early adult age in PGC-1α deficient mice. Along this line, we find that the synergic action of G × E is available in ChABC-infusion PGC-1α KO mice, even though during the adulthood, and the neuroplasticity seems to remain open to fluctuate. Altogether, these results refine the observations made in the PGC-1α deficient mice, a potential mouse model of SZ, and illustrate how PGC-1α regulates CP plasticity via G × E interaction in the developmental trajectory to SZ.

A dual GLP-1 and Gcg receptor agonist rescues spatial memory and synaptic plasticity in APP/PS1 transgenic mice.

Alzheimer's disease (AD) is a neurodegenerative disease that severely affects the health and lifespan of the elderly worldwide. Recently, the correlation between AD and type 2 diabetes mellitus (T2DM) has received intensive attention, and a promising new anti-AD strategy is the use of anti-diabetic drugs. Oxyntomodulin (Oxm) is a peptide hormone and growth factor that acts on neurons in the hypothalamus. OXM activates glucagon-like peptide 1 (GLP-1) and glucagon (Gcg) receptors, facilitates insulin signaling and has neuroprotective effects against Aß1-42-induced cytotoxicity in primary hippocampal neurons. Here, we tested the effects of the protease-resistant analogue (D-Ser2)Oxm on spatial memory and synaptic plasticity and the underlying molecular mechanisms in the APP/PS1 transgenic mouse model of AD. The results showed that (D-Ser2)Oxm not only alleviated the impairments of working memory and long-term spatial memory, but also reduced the number of Aß plaques in the hippocampus, and reversed the suppression of hippocampal synaptic long-term potentiation (LTP). Moreover, (D-Ser2)Oxm administration significantly increased p-PI3K/p-AKT1 expression and decreased p-GSK3ß levels in the hippocampus. These results are the first to show an in vivo neuroprotective role of (D-Ser2)Oxm in APP/PS1 mice, and this role involves the improvement of synaptic plasticity, clearance of Aß and normalization of PI3K/AKT/GSK3ß cell signaling in the hippocampus. This study suggests that (D-Ser2)Oxm holds promise for the prevention and treatment of AD.

Anti-SARS-CoV-2 activities in vitro of Shuanghuanglian preparations and bioactive ingredients.

Human infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19) and there is no cure currently. The 3CL protease (3CLpro) is a highly conserved protease which is indispensable for CoVs replication, and is a promising target for development of broad-spectrum antiviral drugs. In this study we investigated the anti-SARS-CoV-2 potential of Shuanghuanglian preparation, a Chinese traditional patent medicine with a long history for treating respiratory tract infection in China. We showed that either the oral liquid of Shuanghuanglian, the lyophilized powder of Shuanghuanglian for injection or their bioactive components dose-dependently inhibited SARS-CoV-2 3CLpro as well as the replication of SARS-CoV-2 in Vero E6 cells. Baicalin and baicalein, two ingredients of Shuanghuanglian, were characterized as the first noncovalent, nonpeptidomimetic inhibitors of SARS-CoV-2 3CLpro and exhibited potent antiviral activities in a cell-based system. Remarkably, the binding mode of baicalein with SARS-CoV-2 3CLpro determined by X-ray protein crystallography was distinctly different from those of known 3CLpro inhibitors. Baicalein was productively ensconced in the core of the substrate-binding pocket by interacting with two catalytic residues, the crucial S1/S2 subsites and the oxyanion loop, acting as a "shield" in front of the catalytic dyad to effectively prevent substrate access to the catalytic dyad within the active site. Overall, this study provides an example for exploring the in vitro potency of Chinese traditional patent medicines and effectively identifying bioactive ingredients toward a specific target, and gains evidence supporting the in vivo studies of Shuanghuanglian oral liquid as well as two natural products for COVID-19 treatment.

Fabricating cholyglycine-glucose-6-phosphate dehydrogenase conjugates for cholyglycine detection.

To establish cholyglycine (CG) detection via enzyme multiplied immunoassay technique (EMIT), glucose-6-phosphate dehydrogenase (G6PD) was used as a reporter enzyme to prepare hapten-enzyme conjugate. Gel electrophoresis and UV scanning demonstrated that G6PD was successfully labeled with cholyglycine and CG-G6PD conjugate was obtained. Furthermore, the effects of various parameters on the preparation of CG-G6PD conjugates were investigated. Consequently, CG amount, NADH, D-glucose-6-phosphate (G6P), phosphate buffer and the pH, and ionic strength of solution had important effects on the residual activity of CG-G6PD. Moreover, CG amount, the pH, and G6P played important roles in changing CG labeling location on G6PD. Using the CG-G6PD conjugate as test kit, the cholyglycine-EMIT calibration curve was established, which could be employed in clinical detection of cholyglycine. This study provides some valuable information for preparing hapten-G6PD conjugates. This article is protected by copyright. All rights reserved.