Unveiling the mechanism of cysteamine dioxygenase: A combined HPLC-MS assay and metal-substitution approach.

Mammalian cysteamine dioxygenase (ADO), a mononuclear non-heme Fe(II) enzyme with three histidine ligands, plays a key role in cysteamine catabolism and regulation of the N-degron signaling pathway. Despite its importance, the catalytic mechanism of ADO remains elusive. Here, we describe an HPLC-MS assay for characterizing thiol dioxygenase catalytic activities and a metal-substitution approach for mechanistic investigation using human ADO as a model. Two proposed mechanisms for ADO differ in oxygen activation: one involving a high-valent ferryl-oxo intermediate. We hypothesized that substituting iron with a metal that has a disfavored tendency to form high-valent states would discriminate between mechanisms. This chapter details the expression, purification, preparation, and characterization of cobalt-substituted ADO. The new HPLC-MS assay precisely measures enzymatic activity, revealing retained reactivity in the cobalt-substituted enzyme. The results obtained favor the concurrent dioxygen transfer mechanism in ADO. This combined approach provides a powerful tool for studying other non-heme iron thiol oxidizing enzymes.

Research progress on predictive models for malnutrition in cancer patients.

Disease-related malnutrition is a prevalent issue among cancer patients, affecting approximately 40-80% of those undergoing treatment. This condition is associated with numerous adverse outcomes, including extended hospitalization, increased morbidity and mortality, delayed wound healing, compromised muscle function and reduced overall quality of life. Moreover, malnutrition significantly impedes patients' tolerance of various cancer therapies, such as surgery, chemotherapy, and radiotherapy, resulting in increased adverse effects, treatment delays, postoperative complications, and higher referral rates. At present, numerous countries and regions have developed objective assessment models to predict the risk of malnutrition in cancer patients. As advanced technologies like artificial intelligence emerge, new modeling techniques offer potential advantages in accuracy over traditional methods. This article aims to provide an exhaustive overview of recently developed models for predicting malnutrition risk in cancer patients, offering valuable guidance for healthcare professionals during clinical decision-making and serving as a reference for the development of more efficient risk prediction models in the future.

Stacking self-gluing cellulose II films: A facile strategy for the formation of novel all-cellulose laminates.

Cellulose laminates represent a remarkable convergence of natural materials and modern engineering, offering a wide range of versatile applications in sustainable packaging, construction, and advanced materials. In this study, novel all-cellulose laminates are developed using an environmentally friendly approach, where freshly regenerated cellulose II films are stacked without the need for solvents (for impregnation and/or partial dissolution), chemical modifications, or resins. The structural and mechanical properties of these all-cellulose laminates were thoroughly investigated. This simple and scalable procedure results in transparent laminates with exceptional mechanical properties comparable to or even superior to common plastics, with E-modulus higher than 9 GPa for a single layer and 7 GPa for the laminates. These laminates are malleable and can be easily patterned. Depending on the number of layers, they can be thin and flexible (with just one layer) or thick and rigid (with three layers). Laminates were also doped with 10 wt% undissolved fibers without compromising their characteristics. These innovative all-cellulose laminates present a robust, eco-friendly alternative to traditional synthetic materials, thus bridging the gap between environmental responsibility and high-performance functionality.

Global, regional, and national burden of fungal skin diseases in 204 countries and territories from 1990 to 2021: An analysis of the global burden of disease study 2021.

BACKGROUND: Fungal skin diseases are common skin diseases with a heterogeneous distribution worldwide. OBJECTIVES: This study aimed to analyse the spatiotemporal trends in the burden of fungal skin diseases at global, regional, and national levels from 1990 to 2021. METHODS: Based on the data obtained from the Global Burden of Disease Study (GBD) 2021, we described the incident cases, prevalent cases, number of disability-adjusted life years (DALYs), and corresponding age-standardised rates (ASRs) for fungal skin diseases in 1990 and 2021 by sex, age, socio-demographic index (SDI), 21 GBD regions, and 204 countries and territories. We used Joinpoint regression analysis to assess the temporal trends in burden of fungal skin diseases during 1990 to 2021. Spearman's rank test was used to analyse the relationship between disease burden and potential factors. RESULTS: From 1990 to 2021, the incident cases, prevalent cases, and DALYs for fungal skin diseases worldwide increased by 67.93%, 67.73%, and 66.77%, respectively. Globally, the age-standardised incidence rate (ASIR), age-standardised prevalence rate (ASPR), and age-standardised DALYs rate (ASDR) for fungal skin diseases in 2021 were 21668.40 per 100,000 population (95% UI: 19601.19-23729.17), 7789.55 per 100,000 population (95% UI: 7059.28-8583.54), and 43.39 per 100,000 population (95% UI: 17.79-89.10), respectively. Between 1990 and 2021, the ASIR, ASPR, and ASDR for fungal skin diseases have modestly increased, with AAPC of 11.71% (95% confidence interval [CI]: 11.03%-12.39%), 19.24% (95% CI: 18.12%-20.36%), and 20.25% (95% CI: 19.33%-21.18%), respectively. Males experienced a higher burden of fungal skin diseases than females. The incident cases, prevalent cases, and DALYs for fungal skin diseases were highest at the age of 5-9, while the ASRs were highest among the elderly. At national level, the highest ASRs were observed in Nigeria, Ethiopia, and Mali. Overall, SDI was negatively correlated with the ASRs, whereas Global Land-Ocean Temperature Index (GLOTI) was remarkably positively correlated with the burden of fungal skin diseases. CONCLUSIONS: Between 1990 and 2021, the global burden of fungal skin diseases has increased, causing a high disease burden worldwide, particularly in underdeveloped regions and among vulnerable population such as children and the elderly. With global warming and aging of the population, the burden of fungal skin diseases may continue to increase in the future. Targeted and specific measures should be taken to address these disparities and the ongoing burden of fungal skin diseases.

Is there an association between serum 25-hydroxyvitamin D concentrations and obstructive sleep apnoea? A cross-sectional analysis of NHANES 2007-2008 data.

OBJECTIVES: The study aimed to investigate the relationship between serum 25-hydroxyvitamin D (25(OH)D) concentrations and obstructive sleep apnoea (OSA) and to assess the confounding effect of body mass index (BMI) on this relationship. DESIGN: This was a cross-sectional analysis using data from the 2007-08 National Health and Nutrition Examination Survey (NHANES). SETTING: Data were sourced from NHANES, a continuous survey sponsored by the Centres for Disease Control and Prevention, covering residents from 15 urban areas in the United States of America(USA). PARTICIPANTS: The study included 4901 participants aged 16 years and older who had completed 25(OH)D data and responses to the OSA questionnaire. MAIN EXPOSURE MEASURE: Serum 25(OH)D concentrations were measured using liquid chromatography-tandem mass spectrometry. MAIN OUTCOME MEASURE: The primary outcome was the self-reported diagnosis of OSA from questionnaires. RESULTS: After adjusting for age, sex and race (model 1), a significant negative association was observed between 25(OH)D and OSA (ß=-3.21, 95% CI: -6.17 to -0.26). However, this association was no longer significant after further adjustment for BMI (model 2) (ß=1.47, 95% CI: -1.48, 4.42). In the fully adjusted model (model 3), there was no significant association between 25(OH)D and OSA (ß=0.92, 95% CI: -1.93, 3.76). Subgroup analyses stratified by sex, age, race or BMI also revealed no significant associations between 25(OH)D and OSA. CONCLUSIONS: The study found no significant association between 25(OH)D and OSA. The observed correlation between lower levels of 25(OH)D and OSA may be due to confounding factors, such as higher BMI in the OSA group. Therefore, improving obesity management in OSA patients may be necessary to prevent 25(OH)D insufficiency. This underscores the importance of comprehensive management of both OSA and obesity to promote optimal health outcomes.

Corrigendum: The relationship between heavy metals and metabolic syndrome using machine learning.

[This corrects the article DOI: 10.3389/fpubh.2024.1378041.].

Symbiosis of a lytic bacteriophage and Yersinia pestis and characteristics of plague in Marmota himalayana.

Surveillance for animal plague was conducted in the Marmota himalayana plague focus of the Qinghai-Tibet Plateau from 2020 to 2023. A 22.89% positive rate of serum F1 antibody was detected in live-caught marmots, alongside a 43.40% incidence of Yersinia pestis isolation from marmot carcasses. Marmot carcasses infected with plague exhibited a significantly higher spleen-somatic index (P < 0.05). Twenty-one Y. pestis-specific phages were isolated, among which one Y. pestis lytic phage (AKS2022HT87GU_phi) was isolated from the bone marrow of a marmot carcass (no. AKS2022HT87) and was found to be symbiotic with Y. pestis. Microscopy revealed the coexistence of lysed and non-lysed colonies of Y. pestis AKS2022HT87. Genome-wide analysis showed that certain strains of the Y. pestis AKS2022HT87 carried phage DNA fragments consistent with phage AKS2022HT87GU_phi. The rare symbiotic relationship between a lytic phage and Y. pestis observed in vitro was highlighted in this study, laying the basis for further exploring the relationship between Y. pestis and its bacteriophages.IMPORTANCEBacteriophages and host bacteria commonly coexist in vivo or in soil environments through complex and interdependent microbial interactions. However, recapitulating this symbiotic state remains challenging in vitro due to limited medium nutrients. In this work, the natural symbiosis between Yersinia pestis and specific phages has been discovered in a Marmota himalayana specimen. Epidemiological analysis presented the characteristics of the Y. pestis and specific phages in the area with a strong plague epidemic. Crucially, comparative genomics has been conducted to analyze the genetic changes in both the Y. pestis and phages over different periods, revealing the dynamic and evolving nature of their symbiosis. These are the critical steps to study the mechanism of the symbiosis.

Supramolecular Chiral Aggregation of Porphyrin Induced by Photo-Generated Triphenylamines Radical Cations.

Here, it is shown that photoirradiation triggered chiral J-aggregates formation of an achiral anionic porphyrin, TPPS (tetrakis(4-sulfonatophenyl) porphyrin), in the presence of chiral triphenylamine (TPA) derivatives. A series of chiral triarylamines linked with aromatic rings is designed through urea or amide bonds. UV-irradiation of self-assembled urea-linked triphenylamine derivatives causes the formation of persistent radical cations in the chlorinated solvents, which subsequently induces the aggregation of TPPS. Transferring chirality of TPA derivatives to achiral TPPS J-aggregates leads to the chiral assemblies with remarkable chiroptical signals. The experimental results demonstrate that, TPA derivatives linked by the urea bond can effectively promote the aggregation of TPPS rather than those with the amide bond although the photo-generated radical cations are both produced. It is suggested that the urea-linked TPA derivatives are more favorable to stable radical cations and thus cause the formation of TPPS chiral J-aggregation. This work may open up an avenue for designing photo-modulated chiral supramolecular assemblies.

Sex differences in the association between sleep duration and muscle quality index in adults: A cross-sectional study from NHANES 2011-2014.

OBJECTIVE: The aim of this study was to investigate the association between sleep duration and muscle quality index (MQI) in middle-aged and older age groups, as limited evidence exists on this topic. METHODS: In order to assess the relationship between sleep duration and MQI, a cross-sectional study was undertaken, utilizing data from the National Health and Nutrition Examination Survey (NHANES) acquired during the period from 2011 to 2014. The study comprised a total of 4598 participants aged 20 years and above. To examine the association between sleep duration and MQI, sophisticated weighted multivariate linear regression models were employed. Additionally, smooth curve fitting techniques were applied to examine the possibility of any non-linear relationship between the two variables. RESULTS: The average age of the adults who were enrolled in the study was 38.48±11.69 years, and 46.75% of them were female. The results of the multivariable linear regression models showed that sleep duration had a positive correlation with MQI. However, when subgroup analysis was conducted, it was found that this positive correlation only existed among women (ß = 0.09, 95% CI: 0.014 to 0.167). To further confirm the differences between sexes in the relationship between sleep duration and MQI, a weighted generalized additive model (GAM) was used. CONCLUSIONS: This research study provides evidence that there is a positive correlation between the duration of sleep and MQI specifically in females, while no such association was observed in males. These findings shed light on the existence of gender disparities in the connection between sleep duration and MQI.

Association between obstructive sleep apnea and risk of lung cancer: findings from a collection of cohort studies and Mendelian randomization analysis.

Background: Previous cohort studies conducted on large populations have suggested a potential association between obstructive sleep apnea (OSA) and an elevated risk of developing lung cancer. However, limited research has comprehensively investigated the correlation between the two conditions, and the causal effect remains unknown. Methods: A comprehensive and systematic search was conducted across various databases, including PubMed, Web of Science, Cochrane Library, and Embase, from their inception dates to November 1, 2023. To assess the relationship between OSA and lung cancer, a meta-analysis was performed. Additionally, a two-sample Mendelian randomization (MR) study was conducted using summary data. The datasets included 336,659 individuals from the FinnGen study for OSA and 27,209 individuals from the International Lung Cancer Consortium study, as well as 420,473 individuals from the UK Biobank study for lung cancer. The estimates from each study were aggregated using the inverse variance-weighted method. Results: Data from six population-based cohort studies, encompassing 6,589,725 individuals, indicated a significant increase in the risk of developing lung cancer among patients with OSA (HR 1.28, 95% CI 1.07-1.54). However, the MR analysis did not support a causal relationship between OSA and lung cancer (OR 1.001, 95% CI 0.929-1.100). This lack of association was consistent across specific subtypes of lung cancer, including non-small-cell lung cancer (OR 1.000, 95% CI 0.999-1.000, p = 0.974), lung adenocarcinoma (OR 0.996, 95% CI 0.906-1.094, p = 0.927), and squamous cell lung carcinoma (OR 1.034, 95% CI 0.937-1.140, p = 0.507). Conclusions: Our meta-analysis findings suggest an elevated risk of lung cancer among individuals with OSA. However, the MR analysis did not provide evidence supporting a causal relationship between OSA and lung cancer. Further investigation is required to uncover the underlying factors contributing to the observed association between OSA and lung cancer risk.

Development of a nomogram for predicting malnutrition in elderly hospitalized cancer patients: a cross-sectional study in China.

Objectives: The Patient-Generated Subjective Global Assessment (PG-SGA) serves as a specialized nutritional assessment instrument designed for cancer patients. Despite its specificity, the complexity and time requirements of this tool, along with the necessity for administration by trained professionals, limit its practicality in clinical settings. Our objective is to identify a straightforward, efficient, and dependable nutritional assessment tool to promote broader adoption in clinical practice. Methods: This study encompassed a total of 450 patients diagnosed with cancer. Of these, 315 individuals constituted the training set, and the remaining 135 were allocated to the external validation set. The model variables were identified through the Least Absolute Shrinkage and Selection Operator (LASSO) regression method. Binary logistic regression outcomes facilitated the development of a nomogram, offering a visual depiction of the predicted probabilities. The predictive accuracy of the nomogram model was evaluated by calculating the area under the Receiver Operating Characteristic (ROC) curve. Results: The LASSO method detected four variables that were included in the final prediction model: age, serum albumin levels (ALB), body mass index (BMI), and activities of daily living (ADL). The area under the curve (AUC) for this prediction model was 0.905. Both the internal and external calibration curves for malnutrition showed that the predictive nomogram model was highly accurate. Conclusion: The study has developed a prediction model that demonstrates remarkable accuracy in forecasting malnutrition. Furthermore, it presents a streamlined nutritional assessment tool aimed at swiftly identifying cancer patients at nutritional risk, thereby facilitating oncologists in delivering targeted nutritional support to these individuals.

The effect of fascia iliaca compartment block on postoperative delirium in elder adults undergoing hip surgery: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: This meta-analysis aimed to evaluate whether fascia iliaca compartment block (FIB) could reduce the incidence of postoperative delirium (POD) in elderly patients undergoing hip surgery. METHODS: This meta-analysis was registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42023490399). The PubMed, Embase, Web of Science, and Cochrane Library databases were searched for randomized controlled trials (RCTs) till November 15, 2023. Review Manger 5.4 was used to analyze the data. RESULTS: A total of 10 RCTs with 930 elderly patients were included in this meta-analysis. This meta-analysis indicated that FIB could reduce the incidence of POD in elderly patients undergoing hip surgery without preoperative cognitive impairment (OR:0.46; 95%CI[0.22, 0.96], P = 0.04, I2 = 0%). Subgroup analysis of the incidence of POD showed that elderly patients who received FIB treatment before entering the operating room had a lower risk of developing POD(OR:0.48; 95%CI[0.30, 0.76], P = 0.002, I2 = 0%), and FIB could reduce the occurrence of POD in patients undergoing intravertebral anesthesia instead of general anesthesia (OR:0.37; 95%CI[0.20, 0.66], P﹤0.01, I2 = 0%). Moreover, FIB could reduce the MMSE score on the first day after surgery (SMD:1.07; 95%CI[0.15, 1.99], P = 0.02, I2 = 86%). In addition, FIB could reduce the pain score on the first and third day after surgery (SMD: -0.46; 95%CI[-0.74, -0.18], P = 0.001, I2 = 43%; SMD: -0.62; 95%CI[-0.97, -0.26], P﹤0.001, I2 = 58%), as well as after physical activity(SMD: -1.64; 95%CI[-3.00, -0.28], P = 0.02, I2 = 83%). CONCLUSION: FIB can reduce the incidence of POD in elderly patients undergoing hip surgery without pre-existing cognitive impairment. Additionally, it can lower the delirium scores and pain scores.

Transplantation of olfactory mucosa mesenchymal stromal cells repairs spinal cord injury by inducing microglial polarization.

STUDY DESIGN: Animal studies OBJECTIVES: To evaluate the therapeutic effect of olfactory mucosa mesenchymal stem cell (OM-MSCs) transplantation in mice with spinal cord injury (SCI) and to explore the mechanism by which OM-MSCs inhibit neuroinflammation and improve SCI. SETTING: Xiangya Hospital, Central South University; Affiliated Hospital of Guangdong Medical University. METHODS: Mice (C57BL/6, female, 6-week-old) were randomly divided into sham, SCI, and SCI + OM-MSC groups. The SCI mouse model was generated using Allen's method. OM-MSCs were immediately delivered to the lateral ventricle after SCI using stereotaxic brain injections. One day prior to injury and on days 1, 5, 7, 14, 21, and 28 post-injury, the Basso Mouse Scale and Rivlin inclined plate tests were performed. Inflammation and microglial polarization were evaluated using histological staining, immunofluorescence, and qRT-PCR. RESULTS: OM-MSCs originating from the neuroectoderm have great potential in the management of SCI owing to their immunomodulatory effects. OM-MSCs administration improved motor function, alleviated inflammation, promoted the transformation of the M1 phenotype of microglia into the M2 phenotype, facilitated axonal regeneration, and relieved spinal cord injury in SCI mice. CONCLUSIONS: OM-MSCs reduced the level of inflammation in the spinal cord tissue, protected neurons, and repaired spinal cord injury by regulating the M1/M2 polarization of microglia.

Predictive model for assessing malnutrition in elderly hospitalized cancer patients: A machine learning approach.

BACKGROUND: Malnutrition is prevalent among elderly cancer patients. This study aims to develop a predictive model for malnutrition in hospitalized elderly cancer patients. METHODS: Data from January 2022 to January 2023 on cancer patients aged 60+ were collected, involving 22 variables. Key variables were identified using the LASSO (Least Absolute Shrinkage and Selection Operator) method, and nine machine learning models were tested. SHAP was used to interpret the XGBoost model. Malnutrition prevalence was assessed. RESULTS: Among 450 participants, 46.4 % were malnourished. Key predictors identified were ADL (Activities of Daily Living), ALB (Albumin), BMI (Body Mass Index) and age. XGBoost had the highest AUC of 0.945, accuracy of 0.872, and sensitivity of 0.968. Higher ADL and age increased malnutrition risk, while lower ALB and BMI reduced it. CONCLUSIONS: The XGBoost model is highly effective in detecting malnutrition in elderly cancer patients, enabling early and rapid nutritional assessments.

Cobalt(II)-Substituted Cysteamine Dioxygenase Oxygenation Proceeds through a Cobalt(III)-Superoxo Complex.

We investigated the metal-substituted catalytic activity of human cysteamine dioxygenase (ADO), an enzyme pivotal in regulating thiol metabolism and contributing to oxygen homeostasis. Our findings demonstrate the catalytic competence of cobalt(II)- and nickel(II)-substituted ADO in cysteamine oxygenation. Notably, Co(II)-ADO exhibited superiority over Ni(II)-ADO despite remaining significantly less active than the natural enzyme. Structural analyses through X-ray crystallography and cobalt K-edge excitation confirmed successful metal substitution with minimal structural perturbations. This provided a robust structural basis, supporting a conserved catalytic mechanism tailored to distinct metal centers. This finding challenges the proposed high-valent ferryl-based mechanism for thiol dioxygenases, suggesting a non-high-valent catalytic pathway in the native enzyme. Further investigation of the cysteamine-bound or a peptide mimic of N-terminus RGS5 bound Co(II)-ADO binary complex revealed the metal center's high-spin (S = 3/2) state. Upon reaction with O2, a kinetically and spectroscopically detectable intermediate emerged with a ground spin state of S = 1/2. This intermediate exhibits a characteristic 59Co hyperfine splitting (A = 67 MHz) structure in the EPR spectrum alongside UV-vis features, consistent with known low-spin Co(III)-superoxo complexes. This observation, unique for protein-bound thiolate-ligated cobalt centers in a protein, unveils the capacities for O2 activation in such metal environments. These findings provide valuable insights into the non-heme iron-dependent thiol dioxygenase mechanistic landscape, furthering our understanding of thiol metabolism regulation. The exploration of metal-substituted ADO sheds light on the intricate interplay between metal and catalytic activity in this essential enzyme.

Glucose-6-phosphate dehydrogenase alleviates epileptic seizures by repressing reactive oxygen species production to promote signal transducer and activator of transcription 1-mediated N-methyl-d-aspartic acid receptors inhibition.

The pathogenesis of epilepsy remains unclear; however, a prevailing hypothesis suggests that the primary underlying cause is an imbalance between neuronal excitability and inhibition. Glucose-6-phosphate dehydrogenase (G6PD) is a key enzyme in the pentose phosphate pathway, which is primarily involved in deoxynucleic acid synthesis and antioxidant defense mechanisms and exhibits increased expression during the chronic phase of epilepsy, predominantly colocalizing with neurons. G6PD overexpression significantly reduces the frequency and duration of spontaneous recurrent seizures. Furthermore, G6PD overexpression enhances signal transducer and activator of transcription 1 (STAT1) expression, thus influencing N-methyl-d-aspartic acid receptors expression, and subsequently affecting seizure activity. Importantly, the regulation of STAT1 by G6PD appears to be mediated primarily through reactive oxygen species signaling pathways. Collectively, our findings highlight the pivotal role of G6PD in modulating epileptogenesis, and suggest its potential as a therapeutic target for epilepsy.

Pharmacokinetics, Mass Balance, Safety, and Tolerability of Obeldesivir in Healthy Participants.

There is an unmet need for safe and efficacious oral therapies for COVID-19 with low potential for drug-drug interactions. Obeldesivir is an orally administered nucleoside prodrug that has shown antiviral potency in nonclinical studies against SARS-CoV-2 and its circulating variants. Obeldesivir is metabolized to the active nucleoside triphosphate (GS-443902), which acts as an inhibitor of the SARS-CoV-2 RNA-dependent RNA polymerase, thereby inhibiting viral RNA synthesis. Here, we report the safety, tolerability, and pharmacokinetics from a first-in-human, randomized, placebo-controlled, phase I study following oral administration of obeldesivir and a phase I, open-label absorption, distribution, metabolism, and excretion study following oral administration of [14C]-obeldesivir. Overall, obeldesivir was safe and well tolerated at single and multiple doses between 100 and 1,600 mg, with low potential for QT prolongation as assessed by QT-concentration analysis. The exposures to GS-441524 increased dose proportionally in the 100-900-mg dose range. GS-441524 accumulated by 35% after twice-daily and 12% after once-daily dosing for 5 days. Dose-proportional increases in the intracellular concentration of GS-443902 were also observed in peripheral blood mononuclar cells. Plasma exposure of GS-441524 was not significantly altered by food intake. Following oral administration of [14C]-obeldesivir (500 mg; 100 µCi), the mean cumulative [14C]-dose recovery was 90.7% with 58.5% in urine and 32.2% in feces. GS-441524 was the predominant plasma component (90% of 14C-area under the concentration-time curve) and was primarily eliminated via renal excretion. Collectively, data from these studies support selection of the obeldesivir 350 mg twice-daily dosing regimen for further evaluation in phase III studies for COVID-19.

Computational Docking as a Tool in Guiding the Drug Design of Rutaecarpine Derivatives as Potential SARS-CoV-2 Inhibitors.

COVID-19 continues to spread around the world. This is mainly because new variants of the SARS-CoV-2 virus emerge due to genomic mutations, evade the immune system and result in the effectiveness of current therapeutics being reduced. We previously established a series of detection platforms, comprising computational docking analysis, S-protein-based ELISA, pseudovirus entry, and 3CL protease activity assays, which allow us to screen a large library of phytochemicals from natural products and to determine their potential in blocking the entry of SARS-CoV-2. In this new screen, rutaecarpine (an alkaloid from Evodia rutaecarpa) was identified as exhibiting anti-SARS-CoV-2 activity. Therefore, we conducted multiple rounds of structure-activity-relationship (SAR) studies around this phytochemical and generated several rutaecarpine analogs that were subjected to in vitro evaluations. Among these derivatives, RU-75 and RU-184 displayed remarkable inhibitory activity when tested in the 3CL protease assay, S-protein-based ELISA, and pseudovirus entry assay (for both wild-type and omicron variants), and they attenuated the inflammatory response induced by SARS-CoV-2. Interestingly, RU-75 and RU-184 both appeared to be more potent than rutaecarpine itself, and this suggests that they might be considered as lead candidates for future pharmacological elaboration.

Glucose uptake in trophoblasts of GDM mice is regulated by the AMPK-CLUT3 signaling pathway.

GDM, as a metabolic disease during pregnancy, regulates GLUT3 translocation by AMPK, thereby affecting glucose uptake in trophoblasts. It provides a new research idea and therapeutic target for alleviating intrauterine hyperglycemia in GDM. STZ was used to construct GDM mice, inject AICAR into pregnant mice, and observe fetal and placental weight; flow cytometry was employed for the detection of glucose uptake by primary trophoblast cells; immunofluorescence was applied to detect the localization of GLUT3 and AMPK in placental tissue; Cocofal microscope was used to detect the localization of GLUT3 in trophoblast cells;qRT-PCR and Western blot experiments were carried out to detect the expression levels of GLUT3 and AMPK in placental tissue; CO-IP was utilized to detect the interaction of GLUT3 and AMPK. Compared with the normal pregnancy group, the weight of the fetus and placenta of GDM mice increased (P < 0.001), and the ability of trophoblasts to take up glucose decreased (P < 0.001). In addition, AMPK activity in trophoblasts and membrane localization of GLUT3 in GDM mice were down-regulated compared with normal pregnant mice (P < 0.05). There is an interaction between GLUT3 and AMPK. Activating AMPK in trophoblasts can up-regulate the expression of GLUT3 membrane protein in trophoblasts of mice (P < 0.05) and increase the glucose uptake of trophoblasts (P < 0.05). We speculate that inhibition of AMPK activity in GDM mice results in aberrant localization of GLUT3, which in turn attenuates glucose uptake by placental trophoblast cells. AICAR activates AMPK to increase the membrane localization of GLUT3 and improve the glucose uptake capacity of trophoblasts.