Integration of Rap1 and Calcium Signaling

Extracellular histones promote TWIK2-dependent potassium efflux and associated NLRP3 activation in alveolar macrophages during sepsis-induced lung injury

BACKGROUND AND AIM

Sepsis-induced acute lung injury (ALI) is a complex and life-threatening condition lacking specific and efficient clinical treatments. Extracellular histones, identified as a novel type of damage-associated molecular patterns, have been implicated in the inflammatory process of ALI. However, further elucidation is needed regarding the precise mechanism through which extracellular histones induce inflammation. The aim of this study was to investigate whether extracellular histones can activate NLRP3 inflammasome-mediated inflammation in alveolar macrophages (AMs) by affecting TWIK2-dependent potassium efflux.

METHODS AND RESULTS

We conducted experiments using cecal ligation and puncture (CLP) C57BL/6 mice and extracellular histone-stimulated LPS-primed MH-S cells. The results demonstrated a significant increase in the levels of extracellular histones in the plasma and bronchoalveolar lavage fluid (BALF) of CLP mice. Furthermore, neutralizing extracellular histone mitigated lung injury and inflammation in CLP-induced ALI mice. In vitro studies confirmed that extracellular histones upregulated the expression of NLRP3 inflammasome activation-related proteins in MH-S cells, and this effect was dependent on increased potassium efflux mediated by the TWIK2 channel on the plasma membrane. Moreover, extracellular histones directly triggered a substantial influx of calcium, leading to increased Rab11 activity and facilitating the trafficking and location of TWIK2 to the plasma membrane.

CONCLUSION

These findings underscore the critical role of extracellular histone-induced upregulation of TWIK2 expression on the plasma membrane of alveolar macrophages (AMs). This upregulation leads to potassium efflux and subsequent activation of the NLRP3 inflammasome, ultimately exacerbating lung inflammation and injury during sepsis.

Effects of spinal cord injury associated exosomes delivered tRF-41 on the progression of spinal cord injury progression

BACKGROUND

Spinal cord injury (SCI) is a devastating neurological and pathological condition. Exosomal tsRNAs have reported to be promising biomarkers for cancer diagnosis and therapy. This study aimed to investigate the roles of SCI-associated exosomes, and related tsRNA mechanisms in SCI.

METHODS

The serum of healthy controls and SCI patients at the acute stage were collected for exosomes isolation, and the two different exosomes were used to treat human astrocytes (HA). The cell viability, apoptosis, and cycle were determined, and the expression of the related proteins were detected by western blot. Then, the two different exosomes were sent for tsRNA sequencing, and four significant known differentially expressed tsRNAs (DE-tsRNAs) were selected for RT-qPCR validation. Finally, tRT-41 was chosen to further explore its roles and related mechanisms in SCI.

RESULTS

After sequencing, 21 DE-tsRNAs were identified, which were significantly enriched in pathways of Apelin, AMPK, Hippo, MAPK, Ras, calcium, PI3K-Akt, and Rap1. RT-qPCR showed that tRF-41 had higher levels in the SCI-associated exosomes. Compared with the control HA, healthy exosomes did not significantly affect the growth of HA cells, but SCI-associated exosomes inhibited viability of HA cells, while promoted their apoptosis and increased the HA cells in G2/M phase; but tRF-41 inhibitor reversed the actions of SCI-associated exosomes. Additionally, SCI-associated exosomes, similar with tRF-41 mimics, down-regulated IGF-1, NGF, Wnt3a, and β-catenin, while up-regulated IL-1β and IL-6; but tRF-41 inhibitor had the opposite actions, and reversed the effects induced by SCI-associated exosomes.

CONCLUSIONS

SCI-associated exosomes delivered tRF-41 may inhibit the growth of HA through regulating Wnt/ β-catenin pathway and inflammation response, thereby facilitating the progression of SCI.

Calcium (Ca2+) hemostasis, mitochondria, autophagy, and mitophagy contribute to Alzheimer's disease as early moderators

This review rigorously investigates the early cerebral changes associated with Alzheimer's disease, which manifest long before clinical symptoms arise. It presents evidence that the dysregulation of calcium (Ca2+) homeostasis, along with mitochondrial dysfunction and aberrant autophagic processes, may drive the disease's progression during its asymptomatic, preclinical stage. Understanding the intricate molecular interplay that unfolds during this critical period offers a window into identifying novel therapeutic targets, thereby advancing the treatment of neurodegenerative disorders. The review delves into both established and emerging insights into the molecular alterations precipitated by the disruption of Ca2+ balance, setting the stage for cognitive decline and neurodegeneration.

LncRNA AC100826.1 regulated PLCB1 to promote progression in non-small cell lung cancer

BACKGROUND

Lung cancer is the most common malignant tumor. In the present study, we identified a long non-coding RNA (lncRNA) AC100826.1 (simplify to Lnc1), which was highly expressed in non-small cell lung cancer (NSCLC) tissues compared with the paracancerous tissues. We also observed the critical role of Lnc1 in regulating the metastasis ability of NSCLC cells.

METHODS

RNA sequencing was performed to detect differential expression levels of lncRNAs in NSCLC tissues and its paracancerous tissues. Effects of Lnc1 on cell proliferation, invasion, and migration were determined by CCK-8, transwell and scratch assays. The xenograft experiment confirmed the effect of Lnc1 on NSCLC cells proliferation and migration abilities in vivo. RT-qPCR and western blots were performed to determine the expression levels of mRNAs and proteins.

RESULTS

The expression level of Lnc1 was related to multiple pathological results, knockdown of Lnc1 can inhibit the proliferation and metastasis abilities of NSCLC cells. silencing phospholipase C, β1(PLCB1) can reverse the promoting effects of overexpression Lnc1 on NSCLC cells proliferation and migration abilities. In addition, the Rap1 signaling pathway was implicated in the regulation of Lnc1 in NSCLC metastasis.

CONCLUSION

Our results suggest that Lnc1 regulated the metastatic ability of NSCLC cells through targeting the PLCB1/Rap1 signal pathway.

Rap1GAP exacerbates myocardial infarction by regulating the AMPK/SIRT1/NF-κB signaling pathway

Rap1 GTPase-activating protein (Rap1GAP) is an important tumor suppressor. The purpose of this study was to investigate the role of Rap1GAP in myocardial infarction (MI) and its potential mechanism. Left anterior descending coronary artery ligation was performed on cardiac-specific Rap1GAP conditional knockout (Rap1GAP-CKO) mice and control mice with MI. Seven days after MI, Rap1GAP expression in the hearts of control mice peaked, the expression of proapoptotic markers (Bax and cleaved caspase-3) increased, the expression of antiapoptotic factors (Bcl-2) decreased, and the expression of the inflammatory factors IL-6 and TNF-α increased; thus, apoptosis occurred, inflammation, infarct size, and left ventricular dysfunction increased, while the heart changes caused by MI were alleviated in Rap1GAP-CKO mice. Mouse heart tissue was obtained for transcriptome sequencing, and gene set enrichment analysis (GSEA) was used to analyze Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. We found that Rap1GAP was associated with the AMPK and NF-κB signaling pathways and that Rap1GAP inhibited AMPK/SIRT1 and activated the NF-κB signaling pathway in model animals. Similar results were observed in primary rat myocardial cells subjected to oxygen-glucose deprivation (OGD) to induce ischemia and hypoxia. Activating AMPK with the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) reversed the damage caused by Rap1GAP overexpression in cardiomyocytes. In addition, the coimmunoprecipitation results showed that exogenous Rap1GAP interacted with AMPK. Rap1GAP was verified to regulate the AMPK SIRT1/NF-κB signaling pathway and exacerbate the damage to myocardial cells caused by ischemia and hypoxia. In conclusion, our results suggest that Rap1GAP promotes MI by modulating the AMPK/SIRT1/NF-κB signaling pathway and that Rap1GAP may be a therapeutic target for MI treatment in the future.

Characterization of lncRNA and mRNA profiles in ciliary body in experimental myopia

Currently, researchers have mainly focused on the role of the tissues of the posterior segment of the eyes in the development of myopia. However, the ciliary body, an anterior ocular tissue that contracts to initiate the process of accommodation, may also play an important role in the progression of myopia due to the increased demand for near work. In the present study, we established a lens-induced myopia (LIM) animal model in guinea pigs and investigated the molecular changes in the ciliary body associated with the development of myopia based on RNA sequencing. As a result, 871 differentially expressed (DE) mRNAs and 19 DE lncRNAs were identified in the ciliary body between the LIM group and the normal control group. In addition, the lncRNA-mRNA co-expression analysis was performed to explore the target genes of lncRNAs, which were mainly enriched in the Rap1 signaling pathway, cytokine-cytokine receptor interaction, and complement and coagulation cascades pathways based on the functional enrichment analysis. Among the target genes of lncRNAs, three hub genes, including Ctnnb1, Pik3r1, and Itgb1, were found to be involved in the Rap1 signaling pathway. Interestingly, two crucial genes, Grk1 and Pde6a, which are mainly expressed in retinal photoreceptors, were enriched in visual perception in the ciliary body in functional analysis and were verified to be expressed in the ciliary body. These findings indicate the molecular pathogenetic role of the ciliary body in myopia and provide new insights into the underlying mechanism of myopia development. Further studies are needed to explore the specific contributions of these identified lncRNAs and mRNAs to the development of myopia.

A statistical method for image-mediated association studies discovers genes and pathways associated with four brain disorders

Brain imaging and genomics are critical tools enabling characterization of the genetic basis of brain disorders. However, imaging large cohorts is expensive and may be unavailable for legacy datasets used for genome-wide association studies (GWASs). Using an integrated feature selection/aggregation model, we developed an image-mediated association study (IMAS), which utilizes borrowed imaging/genomics data to conduct association mapping in legacy GWAS cohorts. By leveraging the UK Biobank image-derived phenotypes (IDPs), the IMAS discovered genetic bases underlying four neuropsychiatric disorders and verified them by analyzing annotations, pathways, and expression quantitative trait loci (eQTLs). A cerebellar-mediated mechanism was identified to be common to the four disorders. Simulations show that, if the goal is identifying genetic risk, our IMAS is more powerful than a hypothetical protocol in which the imaging results were available in the GWAS dataset. This implies the feasibility of reanalyzing legacy GWAS datasets without conducting additional imaging, yielding cost savings for integrated analysis of genetics and imaging.

Transcriptome Analysis of mRNA and lncRNA Related to Muscle Growth and Development in Gannan Yak and Jeryak

The production performance of Jeryak, resulting from the F1 generation of the cross between Gannan yak and Jersey cattle, exhibits a significantly superior outcome compared with that of Gannan yak. Therefore, we used an RNA-seq approach to identify differentially expressed mRNAs (DEMs) and differentially expressed lncRNAs (DELs) influencing muscle growth and development in Gannan yaks and Jeryaks. A total of 304 differentially expressed lncRNAs and 1819 differentially expressed mRNAs were identified based on the screening criteria of |log 2 FC| > 1 and FDR < 0.05. Among these, 132 lncRNAs and 1081 mRNAs were found to be down-regulated, while 172 lncRNAs and 738 mRNAs were up-regulated. GO and KEGG analyses showed that the identified DELs and DEMs were enriched in the entries of pathways associated with muscle growth and development. On this basis, we constructed an lncRNA-mRNA interaction network. Interestingly, two candidate DELs (MSTRG.16260.9 and MSTRG.22127.1) had targeting relationships with 16 (MYC, IGFBP5, IGFBP2, MYH4, FGF6, etc.) genes related to muscle growth and development. These results could provide a basis for further studies on the roles of lncRNAs and mRNAs in muscle growth in Gannan yaks and Jeryak breeds.

Roles of hypoxic environment and M2 macrophage-derived extracellular vesicles on the progression of non-small cell lung cancer

BACKGROUND

Hypoxia contributes to the development of invasive and metastatic cancer cells, and is detrimental to cancer treatment. This study aimed to explore the molecular mechanisms by which hypoxic microenvironments affect hypoxic non-small cell lung cancer (NSCLC) development and the effects of M2 macrophage-derived extracellular vesicles (EVs) on NSCLC cells.

METHODS

A549 cells were cultured in an anoxic incubator for 48 h to construct hypoxic A549 cells, and then normal and hypoxic A549 cells were harvested for RNA sequencing. Next, THP-1 cells were used to induce M2 macrophages, and EVs were isolated from THP-1 cells and M2 macrophages. Cell counting kit-8 and transwell assays were used to determine the viability and migration of hypoxic A549 cells, respectively.

RESULTS

After sequencing, 2426 DElncRNAs and 501 DEmiRNAs were identified in normal A549 cells and hypoxic A549 cells. These DElncRNAs and DEmiRNAs were significantly enriched in "Wnt signaling pathway," "Hippo signaling pathway," "Rap1 signaling pathway," "calcium signaling pathway," "mTOR signaling pathway," and "TNF signaling pathway." Subsequently, ceRNA networks consisting of 4 lncRNA NDRG1 transcripts, 16 miRNAs and 221 target mRNAs were built, and the genes in the ceRNA networks were significantly associated with "Hippo signaling pathway" and "HIF-1 signaling pathway." EVs were successfully extracted from THP-1 cells and M2 macrophages, and M2 macrophage-derived EVs significantly enhanced the viability and migration of hypoxic A549 cells. Finally, M2 macrophage-derived EVs further upregulated the expression of NDRG1-009, NDRG1-006, VEGFA, and EGLN3, while downregulating miR-34c-5p, miR-346, and miR-205-5p in hypoxic A549 cells.

CONCLUSIONS

M2 macrophage-derived EVs may worsen the progression of NSCLC in a hypoxic microenvironment by regulating the NDRG1-009-miR-34c-5p-VEGFA, NDRG1-006-miR-346-EGLN3, NDRG1-009-miR-205-5p-VEGFA, and Hippo/HIF-1 signaling pathways.

Evaluation of Rap1GAP and EPAC1 Gene Expression in Endometriosis Disease

Background

Endometriosis is a female reproductive system disease in which the endometrial tissue is found in other women's organs. Various factors are effective in the development of endometriosis, and because of the interaction of genetics and environmental factors, this disease is a multi-factorial disease. MAPK/ERK and PI3K/Akt/mTOR pathways are activated by growth factors and steroid hormones and are known as two important pathways involved in the processes of growth, proliferation, and survival of endometriosis cells. Raps, monomeric GTPase of the Ras family, are able to activate these pathways independent of Ras. The goal of our study was to evaluate the expression level of Rap1GAP and EPAC1 genes as two important RapGAPs (GTPase-activating proteins) and RapGEFs (guanine nucleotide exchange factors), respectively, in endometriosis tissues and normal endometrium tissues.

Materials and Methods

In this study, 15 samples of women without signs of endometriosis were taken as control samples. Fifteen ectopic and 15 eutopic samples were taken from women with endometriosis using laparoscopic surgery. The expression of EPAC1 and Rap1GAP genes was investigated by the real-time polymerase chain reaction technique, and the results were analyzed by one-way ANOVA test.

Results

EPAC1 upregulated significantly in ectopic tissues compared to eutopic and control tissues. Rap1GAP expression was lower in ectopic tissues compared to control and eutopic tissues.

Conclusions

Based on these results, it may be concluded that changes in the expression of the Rap1GAP and Epca1 genes may play a role in the pathways involved in the pathogenesis, displacement, and migration of endometriosis cells.

Host Cell Rap1b mediates cAMP-dependent invasion by Trypanosoma cruzi

Trypanosoma cruzi cAMP-mediated invasion has long been described, however, the detailed mechanism of action of the pathway activated by this cyclic nucleotide still remains unknown. We have recently demonstrated a crucial role for Epac in the cAMP-mediated invasion of the host cell. In this work, we gathered evidence indicating that the cAMP/Epac pathway is activated in different cells lines. In accordance, data collected from pull-down experiments designed to identify only the active form of Rap1b (Rap1b-GTP), and infection assays using cells transfected with a constitutively active mutant of Rap1b (Rap1b-G12V), strongly suggest the participation of Rap1b as mediator of the pathway. In addition to the activation of this small GTPase, fluorescence microscopy allowed us to demonstrate the relocalization of Rap1b to the entry site of the parasite. Moreover, phospho-mimetic and non-phosphorylable mutants of Rap1b were used to demonstrate a PKA-dependent antagonistic effect on the pathway, by phosphorylation of Rap1b, and potentially of Epac. Finally, Western Blot analysis was used to determine the involvement of the MEK/ERK signalling downstream of cAMP/Epac/Rap1b-mediated invasion.

Soluble cyclase-mediated nuclear cAMP synthesis is sufficient for cell proliferation

cAMP, a key player in many physiological processes, was classically considered to originate solely from the plasma membrane (PM). This view was recently challenged by observations showing that upon internalization GsPCRs can sustain signaling from endosomes and/or the trans-Golgi network (TGN). In this new view, after the first PM-generated cAMP wave, the internalization of GsPCRs and ACs generates a second wave that was strictly associated with nuclear transcriptional events responsible for triggering specific biological responses. Here, we report that the endogenously expressed TSHR, a canonical GsPCR, triggers an internalization-dependent, calcium-mediated nuclear sAC activation that drives PKA activation and CREB phosphorylation. Both pharmacological and genetic sAC inhibition, which did not affect the cytosolic cAMP levels, blunted nuclear cAMP accumulation, PKA activation, and cell proliferation, while an increase in nuclear sAC expression significantly enhanced cell proliferation. Furthermore, using novel nuclear-targeted optogenetic actuators, we show that light-stimulated nuclear cAMP synthesis can mimic the proliferative action of TSH by activating PKA and CREB. Therefore, based on our results, we propose a novel three-wave model in which the "third" wave of cAMP is generated by nuclear sAC. Despite being downstream of events occurring at the PM (first wave) and endosomes/TGN (second wave), the nuclear sAC-generated cAMP (third wave) is sufficient and rate-limiting for thyroid cell proliferation.

Small GTP-binding protein Rap1 mediates EGF and HB-EGF signaling and modulates EGF receptor expression in HTR-8/SVneo extravillous trophoblast cells

Purpose

Extravillous trophoblasts (EVTs) invade the endometrium to establish a fetomaternal interaction during pregnancy. Epidermal growth factor (EGF) and heparin-binding EGF-like growth factor (HB-EGF) stimulate EVT invasion by binding to the EGF receptor (EGFR). We examined the role of the small GTP-binding protein Rap1 in EGF- and HB-EGF-stimulated EVT invasion.

Methods

Expression of Rap1 in the first-trimester placenta was examined by immunohistochemistry. Effect of EGF or HB-EGF on Rap1 activation (GTP-Rap1) and Rap1 knockdown on invasion was assessed in EVT cell line (HTR-8/SVneo). In addition, effect of Rap1 knockdown and Rap1GAP (a Rap1 inactivator) overexpression on the activation of EGF signaling and EGFR expression were examined.

Results

Rap1 was expressed by EVTs, villous cytotrophoblasts, and syncytiotrophoblasts in the placenta. EGF and HB-EGF activated Rap1 and promoted invasion of HTR-8/SVneo, and these effects were inhibited by Rap1 knockdown. The EGF- and HB-EGF-induced phosphorylation of AKT, ERK1/2, p38MAPK, and Src was inhibited by Rap1 knockdown. Furthermore, the knockdown of Rap1 reduced the EGFR protein level. Overexpression of Rap1GAP repressed EGF- and HB-EGF-induced Rap1 activation and reduced EGFR expression.

Conclusion

Rap1 may function as a mediator of EGF and HB-EGF signaling pathways and can modulate EGFR expression in EVTs during placental development.

DARPP-32/protein phosphatase 1 regulates Rasgrp2 as a novel component of dopamine D1 receptor signaling in striatum

Dopamine regulates psychomotor function by D1 receptor/PKA-dependent phosphorylation of DARPP-32. DARPP-32, phosphorylated at Thr34 by PKA, inhibits protein phosphatase 1 (PP1), and amplifies the phosphorylation of other PKA/PP1 substrates following D1 receptor activation. In addition to the D1 receptor/PKA/DARPP-32 signaling pathway, D1 receptor stimulation is known to activate Rap1/ERK signaling. Rap1 activation is mediated through the phosphorylation of Rasgrp2 (guanine nucleotide exchange factor; activation) and Rap1gap (GTPase-activating protein; inhibition) by PKA. In this study, we investigated the role of PP1 inhibition by phospho-Thr34 DARPP-32 in the D1 receptor-induced phosphorylation of Rasgrp2 and Rap1gap at PKA sites. The analyses in striatal and NAc slices from wild-type and DARPP-32 knockout mice revealed that the phosphorylation of Rasgrp2 at Ser116/Ser117 and Ser586, but not of Rasgrp2 at Ser554 or Rap1gap at Ser441 or Ser499 induced by a D1 receptor agonist, is under the control of the DARPP-32/PP1. The results were supported by pharmacological analyses using a selective PP1 inhibitor, tautomycetin. In addition, analyses using a PP1 and PP2A inhibitor, okadaic acid, revealed that all sites of Rasgrp2 and Rap1gap were regulated by PP2A. Thus, the interactive machinery of DARPP-32/PP1 may contribute to efficient D1 receptor signaling via Rasgrp2/Rap1 in the striatum.

PGCLCs of human 45,XO reveal pathogenetic pathways of neurocognitive and psychosocial disorders

Background

Neurocognitive disorders and psychosocial difficulties are common in patients with Turner syndrome and multiple neurodegenerative diseases, yet there is no effective cure. Human primordial germ cells (hPGCs) are pluripotent germline stem cells in early embryo, which pass genetic information from one generation to the next, whereas all somatic cells will die along with the end of life. However, it is not known whether patient hPGCs with Turner syndrome contain information of neurocognitive and psychosocial illness.

Results

In this report, we used a high-density of culture system of embryoids derived from iPSCs of a patient with Turner syndrome to ask how pathogenetic pathways are associated with onset of neurocognitive and psychosocial disorders. The hPGC-Like Cells (hPGCLCs) were in vitro specified from iPSCs of 45,XO, 46,XX and 46,XY by the high-density induction of embryoids. Amazingly, we found that the specification process of the hPGCLCs in 45,XO, compared to those in 46,XX and 46,XY, enriched several common pathogenetic pathways regulating neurocognitive and psychosocial disorders, that shared among multiple neurodegenerative diseases and Turner syndrome. The downregulated chemical synaptic transmission pathways, including glutamatergic, GABAergic, and nicotine cholinergic synapses, indicated synaptic dysfunctions, while upregulated pathways that were associated with imbalance of mitochondrial respiratory chain complexes and apoptosis, may contribute to neuronal dysfunctions. Notably, downregulation of three types of ubiquitin ligases E1-E2-E3 and lysosome-associated sulfatases and RAB9A, owing to haploinsufficiency and parental preference of the X chromosome expression, indicated that two pathways of cellular degradation, lysosome and ubiquitin–proteasome, were impaired in the specification process of 45,XO hPGCLCs. This would lead to accumulation of undesired proteins and aggregates, which is a typically pathological hallmark in neurodegenerative diseases.

Conclusions

Our data suggest that the specification process of the hPGCLCs in 45,XO, compared to those in 46,XX and 46,XY, enriched pathogenetic pathways that are associated with the onset of neurocognitive and psychosocial disorders.

Differential RNA methylation analysis for MeRIP-seq data under general experimental design

MOTIVATION

RNA epigenetics is an emerging field to study the post-transcriptional gene regulation. The dynamics of RNA epigenetic modification have been reported to associate with many human diseases. Recently developed high-throughput technology named Methylated RNA Immunoprecipitation Sequencing (MeRIP-seq) enables the transcriptome-wide profiling of N6-methyladenosine (m6A) modification and comparison of RNA epigenetic modifications. There are a few computational methods for the comparison of mRNA modifications under different conditions but they all suffer from serious limitations.

RESULTS

In this work, we develop a novel statistical method to detect differentially methylated mRNA regions from MeRIP-seq data. We model the sequence count data by a hierarchical negative binomial model that accounts for various sources of variations and derive parameter estimation and statistical testing procedures for flexible statistical inferences under general experimental designs. Extensive benchmark evaluations in simulation and real data analyses demonstrate that our method is more accurate, robust and flexible compared to existing methods.

AVAILABILITY AND IMPLEMENTATION

Our method TRESS is implemented as an R/Bioconductor package and is available at https://bioconductor.org/packages/devel/TRESS.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Repair of Large-Scale Rib Defects Based on Steel-Reinforced Concrete-Designed Biomimetic 3D-Printed Scaffolds with Bone-Mineralized Microenvironments

Tissue engineering technology provides a promising approach for large-scale bone reconstruction in cases of extensive chest wall defects. However, previous studies did not consider meticulous scaffold design specific to large-scale rib regeneration in terms of three-dimensional (3D) shape, proper porous structures, enough mechanical strength, and osteogenic microenvironments. Thus, there is an urgent need to develop an appropriate bone biomimetic scaffold (BBS) to address this problem. In this study, a BBS with controllable 3D morphology, appropriate mechanical properties, good biocompatibility and biodegradability, porous structure suitable for cell loading, and a biomimetic osteogenic inorganic salt (OIS) microenvironment was successfully prepared by integrating computer-aided design, 3D-printing, cast-molding, and freeze-drying technologies. The addition of the OIS in the scaffold substantially promoted ectopic bone regeneration in vivo, which might be attributed to the activation of osteogenic and angiogenic signaling pathways as well as upregulated expression of osteogenic genes. More importantly, dual long rib defects could be successfully repaired and medullary cavity recanalized by the rib-shaped mature cortical bone, which might be mediated by the activation of osteoclast signaling pathways. Thus, this paper presents a reliable BBS and proposes a new strategy for the repair of large-scale bone defects.

Therapeutic Mechanism and Key Active Ingredients of Shenfu Injection in Sepsis: A Network Pharmacology and Molecular Docking Approach

At present, although the early treatment of sepsis is advocated, the treatment effect of sepsis is unsatisfactory, and the mortality rate remains high. Shenfu injection (SFI) has been used to treat sepsis with good clinical efficacy. Based on network pharmacology, this study adopted a new research strategy to identify the potential therapeutic targets and key active ingredients of SFI for sepsis from the perspective of the pathophysiology of sepsis. This analysis identified 28 active ingredients of SFI based on UHPLC-QQQ MS, including 18 ginsenosides and 10 aconite alkaloids. 59 targets were associated with the glycocalyx and sepsis pathways. Based on the number of targets related to the pathophysiological process of sepsis, we identified songorine, ginsenoside Rf, ginsenoside Re, and karacoline as the key active ingredients of SFI for the treatment of sepsis. According to the cluster analysis of MCODE and the validation on the GEO dataset, LGALS3, BCHE, AKT1, and IL2 were identified as the core targets. This study further explored the therapeutic mechanism and the key active ingredients of SFI in sepsis and provided candidate compounds for drug development.

Identifying key genes in milk fat metabolism by weighted gene co-expression network analysis

Milk fat is the most important and energy-rich substance in milk, and its content and composition are important reference elements in the evaluation of milk quality. However, the current identification of valuable candidate genes affecting milk fat is limited. IlluminaPE150 was used to sequence bovine mammary epithelial cells (BMECs) with high and low milk fat rates (MFP), the weighted gene co-expression network (WGCNA) was used to analyze mRNA expression profile data in this study. As a result, a total of 10,310 genes were used to construct WGCNA, and the genes were classified into 18 modules. Among them, violet (r = 0.74), yellow (r = 0.75) and darkolivegreen (r =  − 0.79) modules were significantly associated with MFP, and 39, 181, 75 hub genes were identified, respectively. Combining enrichment analysis and differential genes (DEs), we screened five key candidate DEs related to lipid metabolism, namely PI4K2A, SLC16A1, ATP8A2, VEGFD and ID1, respectively. Relative to the small intestine, liver, kidney, heart, ovary and uterus, the gene expression of PI4K2A is the highest in mammary gland, and is significantly enriched in GO terms and pathways related to milk fat metabolism, such as monocarboxylic acid transport, phospholipid transport, phosphatidylinositol signaling system, inositol phosphate metabolism and MAPK signaling pathway. This study uses WGCNA to form an overall view of MFP, providing a theoretical basis for identifying potential pathways and hub genes that may be involved in milk fat synthesis.

Cardiovascular protection associated with cilostazol, colchicine and target of rapamycin inhibitors

ABSTRACT

An alteration in extracellular matrix production by vascular smooth muscle cells is a crucial event in the pathogenesis of vascular diseases such as aging-related, atherosclerosis and allograft vasculopathy. The human target of rapamycin (TOR) is involved in the synthesis of extracellular matrix by vascular smooth muscle cells. TOR inhibitors reduce arterial stiffness, blood pressure, and left ventricle hypertrophy and decrease cardiovascular risk in kidney graft recipients and patients with coronary artery disease and heart allograft vasculopathy. Other drugs that modulate extracellular matrix production such as cilostazol and colchicine have also demonstrated a beneficial cardiovascular effect. Clinical studies have consistently shown that cilostazol confers cardiovascular protection in peripheral vascular disease, coronary artery disease, and cerebrovascular disease. In patients with type 2 diabetes, cilostazol prevents the progression of subclinical coronary atherosclerosis. Colchicine reduces arterial stiffness in patients with Familial Mediterranean Fever and patients with coronary artery disease. Pathophysiological mechanisms underlying the cardioprotective effect of these drugs may be related to interactions between the cytoskeleton, TOR signaling and cyclic AMP synthesis that remain to be fully elucidated. Adult vascular smooth muscle cells exhibit a contractile phenotype and produce little extracellular matrix. Conditions that upregulate extracellular matrix synthesis induce a phenotypic switch toward a synthetic phenotype. TOR inhibition with rapamycin reduces extracellular matrix production by promoting the change to the contractile phenotype. Cilostazol increases the cytosolic level of cyclic AMP, which in turn leads to a reduction in extracellular matrix synthesis. Colchicine is a microtubule-destabilizing agent that may enhance the synthesis of cyclic AMP.

Thromboinflammation in Myeloproliferative Neoplasms (MPN)-A Puzzle Still to Be Solved

Myeloproliferative neoplasms (MPNs), a group of malignant hematological disorders, occur as a consequence of somatic mutations in the hematopoietic stem cell compartment and show excessive accumulation of mature myeloid cells in the blood. A major cause of morbidity and mortality in these patients is the marked prothrombotic state leading to venous and arterial thrombosis, including myocardial infarction (MI), deep vein thrombosis (DVT), and strokes. Additionally, many MPN patients suffer from inflammation-mediated constitutional symptoms, such as fever, night sweats, fatigue, and cachexia. The chronic inflammatory syndrome in MPNs is associated with the up-regulation of various inflammatory cytokines in patients and is involved in the formation of the so-called MPN thromboinflammation. JAK2-V617F, the most prevalent mutation in MPNs, has been shown to activate a number of integrins on mature myeloid cells, including granulocytes and erythrocytes, which increase adhesion and drive venous thrombosis in murine knock-in/out models. This review aims to shed light on the current understanding of thromboinflammation, involvement of neutrophils in the prothrombotic state, plausible molecular mechanisms triggering the process of thrombosis, and potential novel therapeutic targets for developing effective strategies to reduce the MPN disease burden.

Thromboinflammation in Myeloproliferative Neoplasms (MPN)-A Puzzle Still to Be Solved

Myeloproliferative neoplasms (MPNs), a group of malignant hematological disorders, occur as a consequence of somatic mutations in the hematopoietic stem cell compartment and show excessive accumulation of mature myeloid cells in the blood. A major cause of morbidity and mortality in these patients is the marked prothrombotic state leading to venous and arterial thrombosis, including myocardial infarction (MI), deep vein thrombosis (DVT), and strokes. Additionally, many MPN patients suffer from inflammation-mediated constitutional symptoms, such as fever, night sweats, fatigue, and cachexia. The chronic inflammatory syndrome in MPNs is associated with the up-regulation of various inflammatory cytokines in patients and is involved in the formation of the so-called MPN thromboinflammation. JAK2-V617F, the most prevalent mutation in MPNs, has been shown to activate a number of integrins on mature myeloid cells, including granulocytes and erythrocytes, which increase adhesion and drive venous thrombosis in murine knock-in/out models. This review aims to shed light on the current understanding of thromboinflammation, involvement of neutrophils in the prothrombotic state, plausible molecular mechanisms triggering the process of thrombosis, and potential novel therapeutic targets for developing effective strategies to reduce the MPN disease burden.

FABP4 activates the JAK2/STAT2 pathway via Rap1a in the homocysteine-induced macrophage inflammatory response in ApoE-/- mice atherosclerosis

Atherosclerosis is a chronic inflammatory vascular disease, and inflammation plays a critical role in its formation and progression. Elevated serum homocysteine (Hcy) is an independent risk factor for atherosclerosis. Previous studies have shown that fatty acid binding protein 4 (FABP4) plays an important role in macrophage inflammation and lipid metabolism in atherosclerosis induced by Hcy. However, the underlying molecular mechanism of FABP4 in Hcy-induced macrophage inflammation remains unknown. In this study, we found that FABP4 activated the Janus kinase 2/signal transducer and activator of transcription 2 (JAK2/STAT2) pathway in macrophage inflammation induced by Hcy. Of note, we further observed that ras-related protein Rap-1a (Rap1a) induced the Tyr416 phosphorylation and membrane translocation of non-receptor tyrosine kinase (c-Src) to activate the JAK2/STAT2 pathway. In addition, the suppressor of cytokine signaling 1 (SOCS1)-a transcriptional target of signal transducer and activator of transcription (STATs) inhibited the JAK2/STAT2 pathway and Rap1a expression via a negative feedback loop. In summary, these results demonstrated that FABP4 promotes c-Src phosphorylation and membrane translocation via Rap1a to activate the JAK2/STAT2 pathway, contributing to Hcy-accelerated macrophage inflammation in ApoE-/- mice.

1,800 MHz Radiofrequency Electromagnetic Irradiation Impairs Neurite Outgrowth With a Decrease in Rap1-GTP in Primary Mouse Hippocampal Neurons and Neuro2a Cells

Background: With the global popularity of communication devices such as mobile phones, there are increasing concerns regarding the effect of radiofrequency electromagnetic radiation (RF-EMR) on the brain, one of the most important organs sensitive to RF-EMR exposure at 1,800 MHz. However, the effects of RF-EMR exposure on neuronal cells are unclear. Neurite outgrowth plays a critical role in brain development, therefore, determining the effects of 1,800 MHz RF-EMR exposure on neurite outgrowth is important for exploring its effects on brain development.

Objectives: We aimed to investigate the effects of 1,800 MHz RF-EMR exposure for 48 h on neurite outgrowth in neuronal cells and to explore the associated role of the Rap1 signaling pathway.

Material and Methods: Primary hippocampal neurons from C57BL/6 mice and Neuro2a cells were exposed to 1,800 MHz RF-EMR at a specific absorption rate (SAR) value of 4 W/kg for 48 h. CCK-8 assays were used to determine the cell viability after 24, 48, and 72 h of irradiation. Neurite outgrowth of primary hippocampal neurons (DIV 2) and Neuro2a cells was observed with a 20 × optical microscope and recognized by ImageJ software. Rap1a and Rap1b gene expressions were detected by real-time quantitative PCR. Rap1, Rap1a, Rap1b, Rap1GAP, and p-MEK1/2 protein expressions were detected by western blot. Rap1-GTP expression was detected by immunoprecipitation. The role of Rap1-GTP was assessed by transfecting a constitutively active mutant plasmid (Rap1-Gly_Val-GFP) into Neuro2a cells.

Results: Exposure to 1,800 MHz RF-EMR for 24, 48, and 72 h at 4 W/kg did not influence cell viability. The neurite length, primary and secondary neurite numbers, and branch points of primary mouse hippocampal neurons were significantly impaired by 48-h RF-EMR exposure. The neurite-bearing cell percentage and neurite length of Neuro2a cells were also inhibited by 48-h RF-EMR exposure. Rap1 activity was inhibited by 48-h RF-EMR with no detectable alteration in either gene or protein expression of Rap1. The protein expression of Rap1GAP increased after 48-h RF-EMR exposure, while the expression of p-MEK1/2 protein decreased. Overexpression of constitutively active Rap1 reversed the decrease in Rap1-GTP and the neurite outgrowth impairment in Neuro2a cells induced by 1,800 MHz RF-EMR exposure for 48 h.

Conclusion: Rap1 activity and related signaling pathways are involved in the disturbance of neurite outgrowth induced by 48-h 1,800 MHz RF-EMR exposure. The effects of RF-EMR exposure on neuronal development in infants and children deserve greater focus.

Integrated bioinformatics analysis of the anti-atherosclerotic mechanisms of the polysaccharide CM1 from Cordyceps militaris

Cordyceps militaris is a well-known traditional Chinese medicine. Studies have demonstrated that the polysaccharides of C. militaris have various bioactivities. However, their mechanisms of action remain unclear. We previously purified a water-soluble polysaccharide CM1 from C. militaris and found that it has a cholesterol efflux improving capacity. This study further investigates the effect of CM1 in anti-atherosclerosis and its underlying mechanism in apolipoprotein E-deficient mice. Our data indicated that CM1 significantly decreased the total cholesterol and triglyceride in the plasma of mice, and decreased lipid deposition and formation of atherosclerotic plaque in a dose-dependent manner. Integrated bioinformatics analysis revealed that CM1 interacted with multiple signaling pathways, including those involved in lipid metabolism, inflammatory response, oxidoreductase activity and fluid shear stress, to exert its anti-atherosclerotic effect. Molecular technology analysis showed that CM1 enhanced the expression of proteins involved in lipid metabolism, reduced the expression of intercellular adhesion molecule-1 and tumor necrosis factor-α in the aorta, and decreased the content of oxidative products by enhancing the activities of antioxidant enzymes. Microarray analysis and biochemical data indicated that CM1 can improve lipid metabolism, reduce inflammation and oxidative stress. Taken together, CM1 could be used for the treatment of hyperlipidemia and atherosclerotic cardiovascular diseases.

CalDAG-GEFI mediates striatal cholinergic modulation of dendritic excitability, synaptic plasticity and psychomotor behaviors

CalDAG-GEFI (CDGI) is a protein highly enriched in the striatum, particularly in the principal spiny projection neurons (SPNs). CDGI is strongly down-regulated in two hyperkinetic conditions related to striatal dysfunction: Huntington’s disease and levodopa-induced dyskinesia in Parkinson’s disease. We demonstrate that genetic deletion of CDGI in mice disrupts dendritic, but not somatic, M1 muscarinic receptors (M1Rs) signaling in indirect pathway SPNs. Loss of CDGI reduced temporal integration of excitatory postsynaptic potentials at dendritic glutamatergic synapses and impaired the induction of activity-dependent long-term potentiation. CDGI deletion selectively increased psychostimulant-induced repetitive behaviors, disrupted sequence learning, and eliminated M1R blockade of cocaine self-administration. These findings place CDGI as a major, but previously unrecognized, mediator of cholinergic signaling in the striatum. The effects of CDGI deletion on the self-administration of drugs of abuse and its marked alterations in hyperkinetic extrapyramidal disorders highlight CDGI’s therapeutic potential.

Proteome characterisation of extracellular vesicles isolated from heart

Cardiac intercellular communication is critical for heart function and often dysregulated in cardiovascular diseases. While cardiac extracellular vesicles (cEVs) are emerging mediators of signalling, their isolation remains a technical challenge hindering our understanding of cEV protein composition. Here, we utilised Langendorff-collagenase-based enzymatic perfusion and differential centrifugation to isolate cEVs from mouse heart (yield 3-6 μg/heart). cEVs are ∼200 nm, express classical EV markers (Cd63/81/9⁺ , Tsg101⁺ , Pdcd6ip/Alix⁺ ), and are depleted of blood (Alb/Fga/Hba) and cardiac damage markers (Mb, Tnnt2, Ldhb). Comparison with mechanically-derived EVs revealed greater detection of EV markers and decreased cardiac damage contaminants. Mass spectrometry-based proteomic profiling revealed 1721 proteins in cEVs, implicated in proteasomal and autophagic proteostasis, glycolysis, and fatty acid metabolism; essential functions often disrupted in cardiac pathologies. There was striking enrichment of 942 proteins in cEVs compared to mouse heart tissue - implicated in EV biogenesis, antioxidant activity, and lipid transport, suggesting active cargo selection and specialised function. Interestingly, cEVs contain marker proteins for cardiomyocytes, cardiac progenitors, B-cells, T-cells, macrophages, smooth muscle cells, endothelial cells, and cardiac fibroblasts, suggesting diverse cellular origin. We present a method of cEV isolation and provide insight into potential functions, enabling future studies into EV roles in cardiac physiology and disease.

The dopamine D1-D2DR complex in the rat spinal cord promotes neuropathic pain by increasing neuronal excitability after chronic constriction injury

Dopamine D1 receptor (D1DR) and D2 receptor (D2DR) are closely associated with pain modulation, but their exact effects on neuropathic pain and the underlying mechanisms remain to be identified. Our research revealed that intrathecal administration of D1DR and D2DR antagonists inhibited D1-D2DR complex formation and ameliorated mechanical and thermal hypersensitivity in chronic constriction injury (CCI) rats. The D1-D2DR complex was formed in the rat spinal cord, and the antinociceptive effects of D1DR and D2DR antagonists could be reversed by D1DR, D2DR, and D1-D2DR agonists. Gαq, PLC, and IP3 inhibitors also alleviated CCI-induced neuropathic pain. D1DR, D2DR, and D1-D2DR complex agonists all increased the intracellular calcium concentration in primary cultured spinal neurons, and this increase could be reversed by D1DR, D2DR antagonists and Gαq, IP3, PLC inhibitors. D1DR and D2DR antagonists significantly reduced the expression of p-PKC γ, p-CaMKII, p-CREB, and p-MAPKs. Levo-corydalmine (l-CDL), a monomeric compound in Corydalis yanhusuo W.T. Wang, was found to obviously suppress the formation of the spinal D1-D2DR complex to alleviate neuropathic pain in CCI rats and to decrease the intracellular calcium concentration in spinal neurons. l-CDL-induced inhibition of p-PKC γ, p-MAPKs, p-CREB, and p-CaMKII was also reversed by D1DR, D2DR, and D1-D2DR complex agonists. In conclusion, these results indicate that D1DR and D2DR form a complex and in turn couple with the Gαq protein to increase neuronal excitability via PKC γ, CaMKII, MAPK, and CREB signaling in the spinal cords of CCI rats; thus, they may serve as potential drug targets for neuropathic pain therapy.

Effect of Prostanoids on Human Platelet Function: An Overview

Prostanoids are bioactive lipid mediators and take part in many physiological and pathophysiological processes in practically every organ, tissue and cell, including the vascular, renal, gastrointestinal and reproductive systems. In this review, we focus on their influence on platelets, which are key elements in thrombosis and hemostasis. The function of platelets is influenced by mediators in the blood and the vascular wall. Activated platelets aggregate and release bioactive substances, thereby activating further neighbored platelets, which finally can lead to the formation of thrombi. Prostanoids regulate the function of blood platelets by both activating or inhibiting and so are involved in hemostasis. Each prostanoid has a unique activity profile and, thus, a specific profile of action. This article reviews the effects of the following prostanoids: prostaglandin-D₂ (PGD₂), prostaglandin-E₁, -E₂ and E₃ (PGE₁, PGE₂, PGE₃), prostaglandin F_2α (PGF_2α), prostacyclin (PGI₂) and thromboxane-A₂ (TXA₂) on platelet activation and aggregation via their respective receptors.