Icariin Ameliorates D-galactose-induced Cell Injury in Neuron-like PC12 Cells by Inhibiting MPTP Opening.

OBJECTIVE: Icariin (ICA) has a good neuroprotective effect and can upregulate neuronal basal autophagy in naturally aging rats. Mitochondrial dysfunction is associated with brain aging-related neurodegenerative diseases. Abnormal opening of the mitochondrial permeability transition pore (mPTP) is a crucial factor in mitochondrial dysfunction and is associated with excessive autophagy. This study aimed to explore that ICA protects against neuronal injury by blocking the mPTP opening and down-regulating autophagy levels in a D-galactose (D-gal)-induced cell injury model. METHODS: A cell model of neuronal injury was established in rat pheochromocytoma cells (PC12 cells) treated with 200 mmol/L D-gal for 48 h. In this cell model, PC12 cells were pre-treated with different concentrations of ICA for 24 h. MTT was used to detect cell viability. Senescence associated ß-galactosidase (SA-ß-Gal) staining was used to observe cell senescence. Western blot analysis was performed to detect the expression levels of a senescence-related protein (p21), autophagy markers (LC3B, p62, Atg7, Atg5 and Beclin 1), mitochondrial fission and fusion-related proteins (Drp1, Mfn2 and Opa1), and mitophagy markers (Pink1 and Parkin). The changes of autophagic flow were detected by using mRFP-GFP-LC3 adenovirus. The intracellular ultrastructure was observed by transmission electron microscopy. Immunofluorescence was used to detect mPTP, mitochondrial membrane potential (MMP), mitochondrial reactive oxygen species (mtROS) and ROS levels. ROS and apoptosis levels were detected by flow cytometry. RESULTS: D-gal treatment significantly decreased the viability of PC12 cells, and markedly increased the SA-ß-Gal positive cells as compared to the control group. With the D-gal stimulation, the expression of p21 was significantly up-regulated. Furthermore, D-gal stimulation resulted in an elevated LC3B II/I ratio and decreased p62 expression. Meanwhile, autophagosomes and autolysosomes were significantly increased, indicating abnormal activation of autophagy levels. In addition, in this D-gal-induced model of cell injury, the mPTP was abnormally open, the ROS generation was continuously increased, the MMP was gradually decreased, and the apoptosis was increased. ICA effectively improved mitochondrial dysfunction to protect against D-gal-induced cell injury and apoptosis. It strongly inhibited excessive autophagy by blocking the opening of the mPTP. Cotreatment with ICA and an mPTP inhibitor (cyclosporin A) did not ameliorate mitochondrial dysfunction. However, the protective effects were attenuated by cotreatment with ICA and an mPTP activator (lonidamine). CONCLUSION: ICA inhibits the activation of excessive autophagy and thus improves mitochondrial dysfunction by blocking the mPTP opening.

Transcriptomic analysis of epicardial adipose tissue reveals the potential crosstalk genes and immune relationship between type 2 diabetes mellitus and atrial fibrillation.

BACKGROUND: The complex relationship between atrial fibrillation (AF) and type 2 diabetes mellitus (T2DM) suggests a potential role for epicardial adipose tissue (EAT) that requires further investigation. This study employs bioinformatics and experimental approaches to clarify EAT's role in linking T2DM and AF, aiming to unravel the biological mechanisms involved. METHOD: Bioinformatics analysis initially identified common differentially expressed genes (DEGs) in EAT from T2DM and AF datasets. Pathway enrichment and network analyses were then performed to determine the biological significance and network connections of these DEGs. Hub genes were identified through six CytoHubba algorithms and subsequently validated biologically, with further in-depth analyses confirming their roles and interactions. Experimentally, db/db mice were utilized to establish a T2DM model. AF induction was executed via programmed transesophageal electrical stimulation and burst pacing, focusing on comparing the incidence and duration of AF. Frozen sections and Hematoxylin and Eosin (H&E) staining illuminated the structures of the heart and EAT. Moreover, quantitative PCR (qPCR) measured the expression of hub genes. RESULTS: The study identified 106 DEGs in EAT from T2DM and AF datasets, underscoring significant pathways in energy metabolism and immune regulation. Three hub genes, CEBPZ, PAK1IP1, and BCCIP, emerged as pivotal in this context. In db/db mice, a marked predisposition towards AF induction and extended duration was observed, with HE staining verifying the presence of EAT. Additionally, qPCR validated significant changes in hub genes expression in db/db mice EAT. In-depth analysis identified 299 miRNAs and 33 TFs as potential regulators, notably GRHL1 and MYC. GeneMANIA analysis highlighted the hub genes' critical roles in stress responses and leukocyte differentiation, while immune profile correlations highlighted their impact on mast cells and neutrophils, emphasizing the genes' significant influence on immune regulation within the context of T2DM and AF. CONCLUSION: This investigation reveals the molecular links between T2DM and AF with a focus on EAT. Targeting these pathways, especially EAT-related ones, may enable personalized treatments and improved outcomes.

Manufacturing, quality control, and GLP-grade preclinical study of nebulized allogenic adipose mesenchymal stromal cells-derived extracellular vesicles.

BACKGROUND: Human adipose stromal cells-derived extracellular vesicles (haMSC-EVs) have been shown to alleviate inflammation in acute lung injury (ALI) animal models. However, there are few systemic studies on clinical-grade haMSC-EVs. Our study aimed to investigate the manufacturing, quality control (QC) and preclinical safety of clinical-grade haMSC-EVs. METHODS: haMSC-EVs were isolated from the conditioned medium of human adipose MSCs incubated in 2D containers. Purification was performed by PEG precipitation and differential centrifugation. Characterizations were conducted by nanoparticle tracking analysis, transmission electron microscopy (TEM), Western blotting, nanoflow cytometry analysis, and the TNF-α inhibition ratio of macrophage [after stimulated by lipopolysaccharide (LPS)]. RNA-seq and proteomic analysis with liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to inspect the lot-to-lot consistency of the EV products. Repeated toxicity was evaluated in rats after administration using trace liquid endotracheal nebulizers for 28 days, and respiratory toxicity was evaluated 24 h after the first administration. In vivo therapeutic effects were assessed in an LPS-induced ALI/ acute respiratory distress syndrome (ARDS) rat model. RESULTS: The quality criteria have been standardized. In a stability study, haMSC-EVs were found to remain stable after 6 months of storage at - 80°C, 3 months at - 20 °C, and 6 h at room temperature. The microRNA profile and proteome of haMSC-EVs demonstrated suitable lot-to-lot consistency, further suggesting the stability of the production processes. Intratracheally administered 1.5 × 108 particles/rat/day for four weeks elicited no significant toxicity in rats. In LPS-induced ALI/ARDS model rats, intratracheally administered haMSC-EVs alleviated lung injury, possibly by reducing the serum level of inflammatory factors. CONCLUSION: haMSC-EVs, as an off-shelf drug, have suitable stability and lot-to-lot consistency. Intratracheally administered haMSC-EVs demonstrated excellent safety at the tested dosages in systematic preclinical toxicity studies. Intratracheally administered haMSC-EVs improved the lung function and exerted anti-inflammatory effects on LPS-induced ALI/ARDS model rats.

Hydroxychloroquine had neutral effect on long-term risk of malignancy in rheumatoid arthritis patients: A population-based retrospective cohort study.

BACKGROUND: The cancer risk in rheumatoid arthritis (RA) patients has been discussed. Hydroxychloroquine (HCQ) may exert protective effects against malignancy. The study investigated the association between HCQ use and the risk of subsequent malignancy in RA patients. METHODS: Catastrophic illness certificated RA patients were extracted from the National Health Insurance Research Database. The index date was set 180 days after the RA diagnosis date to avoid immortal time bias. Two groups were matched in a 1-to-1 ratio by propensity score regarding age, gender, index date, relevant comorbidities, and comedication. HCQ users prior to the diagnosis of RA were exempted to ensure compliance with the new-user design. Cancers diagnosed before or less than 180 days after the index date were excluded to mitigate protopathic bias. The study adopted the Kaplan-Meier curve and Cox proportional hazards model to examine the association between HCQ use and cancer risk. The assumption of proportional hazard was also tested. RESULTS: Based on strict criteria, we included 492 eligible RA patients and divided them into study and control groups (N = 246 in each group). HCQ users exhibited a neutral risk of cancer relative to the controls (adjusted hazard ratio, 0.99; 95% CI, 0.44-2.21, p > .05). The assumption of proportional hazard was not violated. CONCLUSION: This study does not observe the effect of using HCQ as a primary regimen to prevent cancer in RA patients. We are assured that HCQ is not associated with an increased risk of subsequent malignancy in RA patients. Further mechanistic research is needed.

Effects of heavy metal and disinfectant on antibiotic resistance genes and virulence factor genes in the plastisphere from diverse soil ecosystems.

Antibiotic-resistance genes (ARGs) are world-wide contaminants posing potential health risks. Quaternary ammonium compounds (QACs) and heavy metals can apply selective pressure on antibiotic resistance. However, there is a lack of evidence regarding their coupled effect on changes in ARGs and virulence factor genes (VFGs) in various soil types and their plastispheres. Herein, we conducted a microcosm experiment to explore the abundances and profiles of ARGs and VFGs in soil plastispheres from three distinct types of soils amended with Cu and disinfectants. The plastispheres enriched the ARGs' abundance compared to soils and stimulated the coupling effect of combined pollutants on promoting the abundances of ARGs and VFGs. Horizontal gene transfer inevitably accelerates the propagation of ARGs and VFGs in plastispheres under pollutant stress. In plastispheres, combined exposure to disinfectants and Cu increased some potential pathogens' relative abundances. Moreover, the combined effect of disinfectants and Cu on ARGs and VFGs changed with soil type in plastispheres, emphasising the necessity to incorporate soil type considerations into health risk assessments for ARGs and VFGs. Overall, this study highlights the high health risks of ARGs under the selective pressure of combined pollutants in plastispheres and provides valuable insights for future risk assessments related to antibiotic resistance.

Selective enrichment of virulence factor genes in the plastisphere under antibiotic and heavy metal pressures.

The growing accumulation of plastic waste in the environment has created novel habitats known as the "plastisphere", where microorganisms can thrive. Concerns are rising about the potential for pathogenic microorganisms to proliferate in the plastisphere, posing risks to human health. However, our knowledge regarding the virulence and pathogenic potential of these microorganisms in the plastisphere remains limited. This study quantified the abundance of virulence factor genes (VFGs) in the plastisphere and its surrounding environments (water and soil) to better assess pathogenic risks. Our findings revealed a selective enrichment of VFGs in the plastisphere, which were attributed to the specific microbial community assembled. The presence of arsenic and ciprofloxacin in the plastisphere exerted additional co-selective pressures, intensifying the enrichment of VFGs. Notably, VFGs that encoded multiple functions or enhanced the survival of host microorganisms (e.g., encoding adherence functions) tended to accumulate in the plastisphere. These versatile and environmentally adaptable VFGs are more likely to be favored by bacteria in the environment, warranting increased attention in future investigations due to their potential for widespread dissemination. In terms of virulence and pathogenicity, this research offers new insights into evaluating pathogen-related risks in the plastisphere.

Colorectal cancer cell-secreted exosomal miRNA N-72 promotes tumor angiogenesis by targeting CLDN18.

Angiogenesis is essential for the growth and metastasis of several malignant tumors including colorectal cancer (CRC). The molecular mechanism underlying CRC angiogenesis has not been fully elucidated. Emerging evidence indicates that secreted microRNAs (miRNAs) may mediate the intercellular communication between tumor cells and neighboring endothelial cells to regulate tumor angiogenesis. In addition, exosomes have been shown to carry and deliver miRNAs to regulate angiogenesis. miRNA N-72 is a novel miRNA that plays a regulatory role in the EGF-induced migration of human amnion mesenchymal stem cells. However, the relation between miRNA N-72 and cancer remains unclear. We here found that CRC cells could secrete miRNA N-72. A high miRNA N-72 level was detected in the serum of CRC patients and the cultured CRC cells. Moreover, the CRC cell-secreted miRNA N-72 could promote the migration, tubulogenesis, and permeability of endothelial cells. In addition, the mouse xenograft model was used to verify the facilitating effects of miRNA N-72 on CRC growth, angiogenesis, and metastasis in vivo. Further mechanism analysis revealed that CRC cell-secreted miRNA N-72 could be delivered into endothelial cells via exosomes, which then inhibited cell junctions of endothelial cells by targeting CLDN18 and consequently promoted angiogenesis. Our findings reveal a novel mechanism of CRC angiogenesis and highlight the potential of secreted miRNA N-72 as a therapeutic target and a biomarker for CRC.

PANoptosis-based molecular subtyping and HPAN-index predicts therapeutic response and survival in hepatocellular carcinoma.

Background: Hepatocellular carcinoma (HCC) is a highly prevalent and fatal cancer. The role of PANoptosis, a novel form of programmed cell death, in HCC is yet to be fully understood. This study focuses on identifying and analyzing PANoptosis-associated differentially expressed genes in HCC (HPAN_DEGs), aiming to enhance our understanding of HCC pathogenesis and potential treatment strategies. Methods: We analyzed HCC differentially expressed genes from TCGA and IGCG databases and mapped them to the PANoptosis gene set, identifying 69 HPAN_DEGs. These genes underwent enrichment analyses, and consensus clustering analysis was used to determine three distinct HCC subgroups based on their expression profiles. The immune characteristics and mutation landscape of these subgroups were evaluated, and drug sensitivity was predicted using the HPAN-index and relevant databases. Results: The HPAN_DEGs were mainly enriched in pathways associated with the cell cycle, DNA damage, Drug metabolism, Cytokines, and Immune receptors. We identified three HCC subtypes (Cluster_1, SFN+PDK4-; Cluster_2, SFN-PDK4+; Cluster_3, SFN/PDK4 intermediate expression) based on the expression profiles of the 69 HPAN_DEGs. These subtypes exhibited distinct clinical outcomes, immune characteristics, and mutation landscapes. The HPAN-index, generated by machine learning using the expression levels of 69 HPAN_DEGs, was identified as an independent prognostic factor for HCC. Moreover, the high HPAN-index group exhibited a high response to immunotherapy, while the low HPAN-index group showed sensitivity to small molecule targeted drugs. Notably, we observed that the YWHAB gene plays a significant role in Sorafenib resistance. Conclusion: This study identified 69 HPAN_DEGs crucial to tumor growth, immune infiltration, and drug resistance in HCC. Additionally, we discovered three distinct HCC subtypes and constructed an HPAN-index to predict immunotherapeutic response and drug sensitivity. Our findings underscore the role of YWHAB in Sorafenib resistance, presenting valuable insights for personalized therapeutic strategy development in HCC.

Ultrasonic sample introduction combined with flame assisted thermal ionization: Pretreatment-free direct mass spectrometry analysis for fraction collecting tubes of preparative liquid chromatography.

Ultrasonic sample introduction combined with flame assisted thermal ionization mass spectrometry (USI-FATI-MS) was developed to monitor the fractions of preparative liquid chromatography. Recently, ultrasound-based sample introduction techniques have achieved great advance in the field of high-throughput analysis. However, it is still a challenge to directly apply these existing techniques to the analysis of macro volume samples (mL level). In this work, ultrasonic sample introduction combined with flame assisted thermal ionization was used for pretreatment-free direct mass spectrometry analysis of micro to macro volume samples (µL-mL level). Utilizing this unique design of ultrasonic sample introduction, liquid sample in the container can be quickly atomized to the gas phase without contact. Then, due to the flame assisted thermal ionization source, desolvation and ionization of the sample droplets will occur immediately. USI-FATI-MS has shown excellent sensitivity, repeatability and great compatibility to solvents and compounds with a wide range of polarity. As a proof of concept, USI-FATI-MS has been applied for rapid monitoring and identification of purified synthetic and natural products in fractions.

Uncovering the mechanism of Kang-ai injection for treating intrahepatic cholangiocarcinoma based on network pharmacology, molecular docking, and in vitro validation.

Objective: Kang-ai injection (KAI) has been a popular adjuvant treatment for solid tumors, but its anti-tumor mechanism in intrahepatic cholangiocarcinoma (ICC) remains poorly understood. This study applied a network pharmacology-based approach to unveil KAI's anti-tumor activity, key targets, and potential pharmacological mechanism in ICC by integrating molecular docking and in vitro validation. Methods: The KAI-compound-target-ICC network was constructed to depict the connections between active KAI compounds and ICC-related targets based on the available data sources. The crucial ingredients, potential targets, and signaling pathways were screened using GO, KEGG enrichment analysis, and the PPI network. Molecular docking was performed to visualize the interactions between hub targets and components. In vitro experiments were carried out to validate the findings. Results: Among the 87 active components of KAI and 80 KAI-ICC-related targets, bioinformatics analysis identified quercetin as a possible candidate. GO and KEGG enrichment analysis indicated that the PI3K-AKT signaling pathway might be essential in ICC pharmacotherapy. The PPI network and its sub-networks screened 10 core target genes, including AKT1 and IL1ß. Molecular docking results showed stable binding between AKT1 and IL1ß with KAI active ingredients. The in vitro experiments confirmed that KAI might suppress the proliferation of ICC cell lines by inhibiting the PI3K/AKT signaling pathway, consistent with the network pharmacology approach and molecular docking predictions. Conclusion: The study sheds light on KAI's biological activity, potential targets, and molecular mechanisms in treating ICC and provides a promising strategy for understanding the scientific basis and therapeutic mechanisms of herbal treatments for ICC. This research has important implications for developing new, targeted therapies for ICC and highlights the importance of network pharmacology-based approaches in investigating complex herbal formulations.

Injectable Temperature-Sensitive Hydrogel Loaded with IL-36Ra for the Relief of Osteoarthritis.

Osteoarthritis (OA) is an inflammatory disease accompanied by synovial joint inflammation, and IL-36 plays an important role in this process. Local application of IL-36 receptor antagonist (IL-36Ra) can effectively control the inflammatory response, thereby protecting cartilage and slowing down the development of OA. However, its application is limited by the fact that it is rapidly metabolized locally. We designed and prepared a temperature-sensitive poly(lactic-co-glycolic acid)-poly(ethylene glycol)-poly(lactic-co-glycolic acid) (PLGA-PEG-PLGA) hydrogel (IL-36Ra@Gel) system carrying IL-36Ra and evaluated its basic physicochemical characteristics. The drug release curve of IL-36Ra@Gel indicated that this system could slowly release the drug over a longer period. Furthermore, degradation experiments showed that it could be largely degraded from the body within 1 month. The biocompatibility-related results showed that it had no significant effect on cell proliferation compared to the control group. In addition, the expression of MMP-13 and ADAMTS-5 was lower in IL-36Ra@Gel-treated chondrocytes than in the control group, and the opposite results appeared in aggrecan and collagen X. After 8 weeks of treatment with IL-36Ra@Gel by joint cavity injection, HE and Safranin O/Fast green staining showed that the degree of cartilage tissue destruction in the IL-36Ra@Gel-treated group was less than those in other groups. Meanwhile, the joints of mice in the IL-36Ra@Gel group had the most intact cartilage surface, the smallest thickness of cartilage erosion, and the lowest OARSI and Mankins score among all groups. Consequently, the combination of IL-36Ra and PLGA-PLEG-PLGA temperature-sensitive hydrogels can greatly improve the therapeutic effect and prolong the drug duration time, thus effectively delaying the progression of degenerative changes in OA, providing a new feasible nonsurgical treatment for OA.

Toxoplasma gondii infection triggers ongoing inflammation mediated by increased intracellular Cl- concentration in airway epithelium.

Toxoplasma gondii is a widespread parasitic protozoan causing toxoplasmosis including pulmonary toxoplasmosis. As the first line of host defense, airway epithelial cells play critical roles in orchestrating pulmonary innate immunity. However, the mechanism underlying the airway inflammation induced by the T. gondii infection remains largely unclear. This study demonstrated that after infection with T. gondii, the major anion channel located in the apical membranes of airway epithelial cells, cystic fibrosis transmembrane conductance regulator (CFTR), was degraded by the parasite-secreted cysteine proteases. The intracellular Cl- concentration ([Cl-]i) was consequently elevated, leading to activation of nuclear factor-κB (NF-κB) signaling via serum/glucocorticoid regulated kinase 1. Furthermore, the heightened [Cl-]i and activated NF-κB signaling could be sustained in a positive feedback regulatory manner resulting from decreased intracellular cAMP level through NF-κB-mediated up-regulation of phosphodiesterase 4. Conversely, the sulfur-containing compound allicin conferred anti-inflammatory effects on pulmonary toxoplasmosis by decreasing [Cl-]i via activation of CFTR. These results suggest that the intracellular Cl- dynamically modulated by T. gondii mediates sustained airway inflammation, which provides a potential therapeutic target against pulmonary toxoplasmosis.

Case report: AngioJet thrombectomy with extracorporeal membrane oxygenation support for acute massive pulmonary embolism in a severe multiple trauma patient.

Acute massive pulmonary embolism (PE) is one of the main leading causes of high cardiovascular mortality, and the prognosis strongly varies, depending on the severity of pulmonary arterial obstruction and its impact on the RV function. Alternative therapy approaches comprise systemic thrombolysis, catheter-directed thrombolysis, catheter embolectomy, catheter-assisted fragmentation techniques, and surgical thrombectomy. The following case study explores a 72-year-old man with severe multiple trauma who suffered from a sudden massive pulmonary embolism and presented with an unstable hemodynamic status. Extracorporeal membrane oxygenation (ECMO) has amply proven its efficacy in supplying cardiopulmonary assistance for this patient shocked by a massive PE with contraindication for thrombolysis. AngioJet catheter embolectomy and ECMO were performed, which finally cleared the massive pulmonary embolism away and improved the patient's hemodynamic status. The use of ECMO was continued during the weaning program, on the fifth day after ECMO decannulation, the patient was extubated and transferred to a local hospital for further recuperation. This case highlights that the AngioJet thrombectomy with the combination use of ECMO may be a potential choice of treatment for unstable PE patients.

Case report: Total percutaneous post-closure of femoral arterial access sites after veno-arterial extracorporeal membrane oxygenation.

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) which is a form of circulatory and gas exchange support. Following VA-ECMO, total percutaneous closure of the site of femoral arterial puncture with perclose Proglide (PP) has become widespread, enhancing patient comfort and lessening the incidence of wound infections and lymphatic fistulas in a short closure time. The preclose technique with perclose Proglide provides numerous benefits, however, it prolongs extra time during the VA-ECMO procedure, adds additional post-operative care to workloads, and increases the potential for Proglide stitch infection. The modified technique-percutaneous post-closure, described here by a case of a 65-year-old man with heart attack who underwent VA-ECMO, is a simple, rapidly applied technique to wean VA-ECMO also suitable for emergency cannulation. The patient was administered mechanically ventilated and sedated and the femoral artery access site and evaluated by ultrasound for precise positioning, then the VA-ECMO arterial cannula was withdrawn, and a 0.035-in guidewire was left in the artery. The first set of sutures was deployed after the Proglide device was inserted over the guidewire. The second sutures were then replaced in the same way but at a different angle. After hemostasis was achieved, the guidewire was removed, and additional manual compression was used to control any residual blood seeping. No hematoma, pseudoaneurysm, major bleeding, minor bleeding, acute arterial thrombosis, arteriovenous fistula, groin infection, lymphocele, or arterial dissection and stenosis occurred during the periprocedural period or during the 30-day post-procedural follow-up. In conclusion, the standardized algorithm we established, total percutaneous post-closure of femoral arteriotomies utilizing Perclose ProGlide device is feasible and safe with a low incidence of access site complications.

Allicin Facilitates Airway Surface Liquid Hydration by Activation of CFTR.

Airway epithelium plays critical roles in regulating airway surface liquid (ASL), the alteration of which causes mucus stasis symptoms. Allicin is a compound released from garlic and harbors the capacity of lung-protection. However, the potential regulatory effects of allicin on airway epithelium remain elusive. This study aimed to investigate the effects of allicin on ion transport across airway epithelium and evaluate its potential as an expectorant. Application of allicin induced Cl- secretion across airway epithelium in a concentration-dependent manner. Blockade of cystic fibrosis transmembrane conductance regulator (CFTR) or inhibition of adenylate cyclase-cAMP signaling pathway attenuated allicin-induced Cl- secretion in airway epithelial cells. The in vivo study showed that inhaled allicin significantly increased the ASL secretion in mice. These results suggest that allicin induces Cl- and fluid secretion across airway epithelium via activation of CFTR, which might provide therapeutic strategies for the treatment of chronic pulmonary diseases associated with ASL dehydration.

SARS-CoV-2 nucleocapsid protein triggers hyperinflammation via protein-protein interaction-mediated intracellular Cl- accumulation in respiratory epithelium.

SARS-CoV-2, the culprit pathogen of COVID-19, elicits prominent immune responses and cytokine storms. Intracellular Cl- is a crucial regulator of host defense, whereas the role of Cl- signaling pathway in modulating pulmonary inflammation associated with SARS-CoV-2 infection remains unclear. By using human respiratory epithelial cell lines, primary cultured human airway epithelial cells, and murine models of viral structural protein stimulation and SARS-CoV-2 direct challenge, we demonstrated that SARS-CoV-2 nucleocapsid (N) protein could interact with Smad3, which downregulated cystic fibrosis transmembrane conductance regulator (CFTR) expression via microRNA-145. The intracellular Cl- concentration ([Cl-]i) was raised, resulting in phosphorylation of serum glucocorticoid regulated kinase 1 (SGK1) and robust inflammatory responses. Inhibition or knockout of SGK1 abrogated the N protein-elicited airway inflammation. Moreover, N protein promoted a sustained elevation of [Cl-]i by depleting intracellular cAMP via upregulation of phosphodiesterase 4 (PDE4). Rolipram, a selective PDE4 inhibitor, countered airway inflammation by reducing [Cl-]i. Our findings suggested that Cl- acted as the crucial pathological second messenger mediating the inflammatory responses after SARS-CoV-2 infection. Targeting the Cl- signaling pathway might be a novel therapeutic strategy for COVID-19.

G protein-coupled estrogen receptor promotes acrosome reaction via regulation of Ca2+ signaling in mouse sperm†.

G protein-coupled estrogen receptor (GPER), a seven-transmembrane G protein-coupled receptor, mediates the rapid pre-genomic signaling actions of estrogen and derivatives thereof. The expression of GPER is extensive in mammal male reproductive system. However, the functional role of GPER in mouse sperm has not yet been well recognized. This study revealed that GPER was expressed at the acrosome and the mid-flagellum of the mouse sperm. The endogenous GPER ligand 17ß-estradiol and the selective GPER agonist G1 increased intracellular Ca2+ concentration ([Ca2+]i) in mouse sperm, which could be abolished by G15, an antagonist of GPER. In addition, the G1-stimulated Ca2+ response was attenuated by interference with the phospholipase C (PLC) signaling pathways or by blocking the cation channel of sperm (CatSper). Chlortetracycline staining assay showed that the activation of GPER increased the incidence of acrosome-reacted sperm. Conclusively, GPER was located at the acrosome and mid-flagellum of the mouse sperm. Activation of GPER triggered the elevation of [Ca2+]i through PLC-dependent Ca2+ mobilization and CatSper-mediated Ca2+ influx, which promoted the acrosome reaction of mouse sperm.

Correlation between Surface Area Ratio of Medial to Lateral Tibial Plateau and Knee Alignment in Adults.

OBJECTIVE: This study aimed to investigate the correlation between the surface area ratio of medial tibial plateau (MTP) to lateral tibial plateau (LTP) and the mechanical tibiofemoral angle (mTFA). METHODS: Lower limb computed tomography (CT) images were collected at our hospital. Then, the original CT data were analyzed and reconstructed using medical image processing software. The proximal and distal centres of the femur and tibia were marked. The surface areas of MTP and LTP were identified using image processing software. GraphPad Prism 8.0.2 was used to perform the statistical analysis. RESULTS: The surface area ratio of MTP to LTP was significantly correlated with the mTFA in all patients (P<0.0001), male group (P<0.0001), female group (P<0.0001), varus group (P<0.0001), and valgus group (P=0.002). Furthermore, the surface area of MTP and LTP was significantly greater in the male group than in the female group (P<0.0001). There was significant difference in the surface area of the MTP between the varus and valgus groups (P<0.0001). Significant difference was also observed in the surface area ratio of MTP to LTP between the varus and valgus groups (P<0.0001). CONCLUSION: The surface area ratio of MTP to LTP was correlated with the mTFA. Within a certain range, the smaller the mTFA, the greater the surface area ratio of MTP to LTP. For patients undergoing total knee arthroplasty, of whom the surface area of the MTP was basically equal to that of the LTP, it is recommended that the osteotomy should be performed in accordance with mechanical alignment standards, and that a symmetrical tibial plateau prosthesis should be used. For patients whose surface area of MTP is significantly greater than that of the LTP, it is recommended that the osteotomy should be performed in accordance with kinematic alignment standards, and that an anatomical tibial plateau prosthesis should be used.