The PI3K/AKT signaling pathway in regulatory T-cell development, stability, and function

The PI3K signaling pathway; from normal lymphopoiesis to lymphoid malignancies

INTRODUCTION

As a vital mechanism of survival, lymphopoiesis requires the collaboration of different signaling molecules to orchestrate each step of cell development and maturation. The PI3K pathway is considerably involved in the maturation of lymphatic cells and therefore, its dysregulation can immensely affect human well-being and cause some of the most prevalent malignancies. As a result, studies that investigate this pathway could pave the way for a better understanding of the lymphopoiesis mechanisms, the undesired changes that lead to cancer progression, and how to design drugs to solve this issue.

AREAS COVERED

The present review addresses the aforementioned aspects of the PI3K pathway and helps pave the way for future therapeutic approaches. In order to access the articles, databases such as Medicine Medline/PubMed, Scopus, Google Scholar, and Science Direct were utilized. The search formula was established by identifying main keywords including PI3K/Akt/mTOR pathway, Lymphopoiesis, Lymphoid malignancies, and inhibitors.

EXPERT OPINION

The PI3K pathway is crucial for lymphocyte development and differentiation, making it a potential target for therapeutic intervention in lymphoid cancers. Studies are focused on developing PI3K inhibitors to impede the progression of hematologic malignancies, highlighting the pathway's significance in lymphoma and lymphoid leukemia.

Molecular Mechanisms of the Therapeutic Effect of Selenium Nanoparticles in Hepatocellular Carcinoma

This review describes and summarizes, for the first time, the molecular mechanisms of the cytotoxic effect of selenium nanoparticles of various origins on hepatocellular carcinoma cells. The text provides information from recent years indicating the regulation of various signaling pathways and endoplasmic reticulum stress by selenium nanoparticles; the pathways of cell death of liver cancer cells as a result of exposure to selenium nanoparticles are considered. Particular attention is paid to the participation of selenoproteins and selenium-containing thioredoxin reductases and glutathione peroxidases in these processes. Previously, there were no reviews that fully reflected the cytotoxic effects of selenium nanoparticles specifically in hepatocellular carcinoma, despite the fact that many reviews and experimental articles have been devoted to the causes of this disease and the molecular mechanisms of regulation of cytotoxic effects by other agents. The relevance of this review is primarily explained by the fact that despite the development of various drugs and approaches for the treatment and prevention of hepatocellular carcinoma, this disease is still the fourth leading cause of death in the world. For this reason, a complete understanding of the latest trends in the treatment of oncology of various etiologies, especially hepatocellular carcinoma, is extremely important.

Inhibition of Lck/Fyn kinase activity promotes the differentiation of induced Treg cells through AKT/mTOR pathway

Regulatory T (Treg) cells are indispensable in maintaining the immune homeostasis and preventing autoimmune diseases. Regulatory T (Treg) cells include thymus derived Treg cells (tTregs) and peripherally induced Treg cells (iTreg), which are differentiated from antigen stimulated CD4+ naïve T cells in presence of TGFβ. tTregs are quite stable, and more immune suppressive, while iTreg cells are less stable, and are prone to differentiate into inflammatory T cells. Therefore, identification of small molecules that could promote the differentiation of iTreg cells is an attractive strategy for autoimmune diseases. Inhibition of AKT/mTOR pathway promotes their differentiation. Whether inhibition of Lck/Fyn kinase activity (upstream of AKT/mTOR pathway) can be used to promote the differentiation of iTreg cells has not been determined. Here, we showed that Srci1, a small molecular inhibitor of Lck/Fyn, promoted the differentiation of FOXP3+ iTreg cells. Srci1 treatment resulted in inhibition of phosphorylation of key components of AKT/mTOR pathway, including mTOR, p70 S6K, 4EBP1, and promoted the expression of Foxp3 and its target genes, thereby promoted differentiation of in vitro iTreg cells. Srci1 treated iTreg cells showed more similar gene expression profile to that of tTreg cells. Our results thus suggest that inhibition of Lck/Fyn kinase activity can promote the differentiation of iTreg cells, and may have implication in autoimmune diseases.

Antibody nanoparticle conjugate-based targeted immunotherapy for non-small cell lung cancer

The use of immune checkpoint inhibitors, which activate T cells, is a paradigm shift in the treatment of non-small cell lung cancer. However, the overall response remains low. To address this limitation, here we describe a novel platform, termed antibody-conjugated drug-loaded nanotherapeutics (ADN), which combines immunotherapy and molecularly targeted therapy. An ADN was designed with an anti-CD47 and anti-programmed death ligand 1 (PDL1) antibody pair on the surface of the nanoparticle and a molecularly targeted inhibitor of the PI3K (phosphatidylinositol 3-kinase)/AKT/mTOR (mammalian target of rapamycin) pathway, PI103, entrapped in the nanoparticle. The anti-CD47-PDL1-ADN exhibited greater antitumor efficacy than current treatment options with a PDL1 inhibitor in vivo in an aggressive lung cancer immunocompetent mouse model. Dual antibody-drug-loaded nanotherapeutics can emerge as an attractive platform to improve outcomes with cancer immunotherapy.

Mechanism of Prunella vulgaris L. and luteolin in restoring Tfh/Tfr balance and alleviating oxidative stress in Graves' disease

BACKGROUND

The pathophysiology of Graves' disease (GD) involves imbalances between follicular helper T (Tfh) and follicular regulatory T (Tfr) cells, as well as oxidative stress (OS). Prunella vulgaris L. (Xia Ku Cao, XKC) and its primary bioactive compound, luteolin, are recognized for their potential in treating GD. Yet, the mechanism accounting for the immune-modulatory and antioxidant effects of XKC remains elusive.

PURPOSE

This study aims to evaluate the pharmacological effects and elucidate the underlying mechanism of XKC and luteolin in a GD mouse model induced by recombinant adenovirus of TSH receptor A subunit (Ad-hTSHR-289).

METHODS

High-Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry (HPLC-QTOF MS) was used to detect the constituents of XKC. The GD model was established through inducing female BALB/c mice with three intramuscular injections of Ad-TSHR-289. Thyroid function, autoantibody and OS parameters were measured by ELISA. Changes of Tfh cells and Tfr cells were detected by flow cytometry. RT-qPCR, Western Blotting, immunohistochemistry were used to explore the related molecular mechanisms.

RESULTS

A total of 37 chemical components from XKC were identified by HPLC-QTOF MS, represented by flavonoids, steroids, terpenoids, and luteolin. XKC and luteolin reduced T4, TRAb levels and facilitated the recovery from thyroid damage in GD mice. Meanwhile, XKC and luteolin effectively alleviated OS by decreasing the levels of MDA, NOX2, 4-HNE, 8-OHdG, while increasing GSH level. Flow cytometry showed that XKC and luteolin restored the abnormal proportions of Tfh/Tfr and Tfh/Treg, and the mRNA levels of IL-21, Bcl-6 and Foxp3 in GD mice. In addition, XKC and luteolin inhibited PI3K, Akt, p-PI3K and p-Akt, but activated Nrf2 and HO-1.

CONCLUSION

XKC and luteolin could inhibit the development of GD in vivo by rebalancing Tfh/Tfr cells and alleviating OS. This therapeutic mechanism may involve the Nrf2/HO-1 and PI3K/Akt signaling pathways. Luteolin is the main efficacy material basis of XKC in countering GD. For the first time, we revealed the mechanism of XKC and luteolin in the treatment of GD from the perspective of autoimmune and OS.

Ephrin B2 (EFNB2) potentially protects against intervertebral disc degeneration through inhibiting nucleus pulposus cell apoptosis

Nucleus pulposus (NP) cell apoptosis is a significant indication of accelerated intervertebral disc degeneration; however, the precise mechanism is unelucidated as of yet. Ephrin B2 (EFNB2), the only gene down-regulated in the three degraded intervertebral disc tissue microarray groups (GSE70362, GSE147383 and GSE56081), was screened for examination in this study. Subsequently, EFNB2 was verified to be down-regulated in degraded NP tissue samples. Interleukin-1 (IL-1β) treatment of NP cells to simulate the IDD environment indicated that IL-1β treatment decreased EFNB2 expression. In degenerative NP cells stimulated by IL-1β, EFNB2 knockdown significantly increased the rate of apoptosis as well as the apoptosis-related molecules cleaved-caspase-3 and the Bax to Bcl-2 ratio. EFNB2 was found to promote AKT, PI3K, and mTOR phosphorylation; the PI3K/AKT signaling role was investigated using the PI3K inhibitor LY294002. EFNB2 overexpression significantly increased PI3K/AKT pathway activity in IL-1β-stimulated NP cells than the normal control. Moreover, EFNB2 partially alleviated NP cell apoptosis induced by IL-1β, reduced the cleaved-cas3 level, and decreased the Bax/Bcl-2 ratio after the addition of the inhibitor LY294002. Additionally, EFNB2 overexpression inhibited the ERK1/2 phosphorylation; the effects of EFNB2 overexpression on ERK1/2 phosphorylation, degenerative NP cell viability, and cell apoptosis were partially reversed by ERK signaling activator Ceramide C6. EFNB2 comprehensively inhibited the apoptosis of NP cells by activating the PI3K/AKT signaling and inhibiting the ERK signaling, obviating the exacerbation of IDD. EFNB2 could be a potential target to protect against degenerative disc changes.

Targeting CXCR4 impaired T regulatory function through PTEN in renal cancer patients

BACKGROUND

Tregs trafficking is controlled by CXCR4. In Renal Cell Carcinoma (RCC), the effect of the new CXCR4 antagonist, R54, was explored in peripheral blood (PB)-Tregs isolated from primary RCC patients.

METHODS

PB-Tregs were isolated from 77 RCC patients and 38 healthy donors (HDs). CFSE-T effector-Tregs suppression assay, IL-35, IFN-γ, IL-10, TGF-β1 secretion, and Nrp-1+Tregs frequency were evaluated. Tregs were characterised for CTLA-4, PD-1, CD40L, PTEN, CD25, TGF-β1, FOXP3, DNMT1 transcriptional profile. PTEN-pAKT signalling was evaluated in the presence of R54 and/or triciribine (TCB), an AKT inhibitor. Methylation of TSDR (Treg-Specific-Demethylated-Region) was conducted.

RESULTS

R54 impaired PB-RCC-Tregs function, reduced Nrp-1+Tregs frequency, the release of IL-35, IL-10, and TGF-β1, while increased IFN-γ Teff-secretion. The CXCR4 ligand, CXCL12, recruited CD25+PTEN+Tregs in RCC while R54 significantly reduced it. IL-2/PMA activates Tregs reducing pAKT+Tregs while R54 increases it. The AKT inhibitor, TCB, prevented the increase in pAKT+Tregs R54-mediated. Moreover, R54 significantly reduced FOXP3-TSDR demethylation with DNMT1 and FOXP3 downregulation.

CONCLUSION

R54 impairs Tregs function in primary RCC patients targeting PTEN/PI3K/AKT pathway, reducing TSDR demethylation and FOXP3 and DNMT1 expression. Thus, CXCR4 targeting is a strategy to inhibit Tregs activity in the RCC tumour microenvironment.

CD93 regulates breast cancer growth and vasculogenic mimicry through the PI3K/AKT/SP2 signaling pathway activated by integrin β1

In women, breast cancer (BC) accounts for 7%-10% of all cancer cases and is one of the most common cancers. To identify a new method for treating BC, the role of CD93 and its underlying mechanism were explored. MDA-MB-231 cells were used in this study and transfected with si-CD93, si-MMRN2, oe-CD93, si-integrin β1, or oe-SP2 lentivirus. After MDA-MB-231 cells were transfected with si-NC or si-CD93, they were injected into nude mice by subcutaneous injection at a dose of 5 × 106/mouse to construct a BC animal model. The expression of genes and proteins and cell migration, invasion and vasculogenic mimicry were detected by RT‒qPCR, western blot, immunohistochemistry, immunofluorescence, Transwell, and angiogenesis assays. In pathological samples and BC cell lines, CD93 was highly expressed. Functionally, CD93 promoted the proliferation, migration, and vasculogenic mimicry of MDA-MB-231 cells. Moreover, CD93 interacts with MMRN2 and integrin β1. Knockdown of CD93 and MMRN2 can inhibit the activation of integrin β1, thereby inhibiting the PI3K/AKT/SP2 signaling pathway and inhibiting BC growth and vasculogenic mimicry. In conclusion, the binding of CD93 to MMRN2 can activate integrin β1, thereby activating the PI3K/AKT/SP2 signaling pathway and subsequently promoting BC growth and vasculogenic mimicry.

OptoREACT: Optogenetic Receptor Activation on Nonengineered Human T Cells

Optogenetics is a versatile and powerful tool for the control and analysis of cellular signaling processes. The activation of cellular receptors by light using optogenetic switches usually requires genetic manipulation of cells. However, this considerably limits the application in primary, nonengineered cells, which is crucial for the study of physiological signaling processes and for controlling cell fate and function for therapeutic purposes. To overcome this limitation, we developed a system for the light-dependent extracellular activation of cell surface receptors of nonengineered cells termed OptoREACT (Optogenetic Receptor Activation) based on the light-dependent protein interaction of A. thaliana phytochrome B (PhyB) with PIF6. In the OptoREACT system, a PIF6-coupled antibody fragment binds the T cell receptor (TCR) of Jurkat or primary human T cells, which upon illumination is bound by clustered phytochrome B to induce receptor oligomerization and activation. For clustering of PhyB, we either used tetramerization by streptavidin or immobilized PhyB on the surface of cells to emulate the interaction of a T cell with an antigen-presenting cell. We anticipate that this extracellular optogenetic approach will be applicable for the light-controlled activation of further cell surface receptors in primary, nonengineered cells for versatile applications in fundamental and applied research.

Transcriptome analysis reveals immune function-related mRNA expression in donkey mammary glands during four developmental stages

The low susceptibility to mastitis of female donkey (jenny) mammary glands and the strong immune properties of donkey milk are acknowledged, but little is known about the genes involved in mammary gland immunity in jennies. Herein, we used RNA-sequencing and bioinformatics analyses to explore jenny mammary gland transcriptomes and detect potential functional differentially expressed (DE) mRNAs related to immunity during four specific developmental stages: foetal (F), pubertal (P), adult parous nonlactation (N) and lactation (L). A total of 2497, 583 and 1820 DE mRNAs were identified in jenny mammary glands at F vs. P, P vs. N, and N vs. L, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) analyses revealed numerous GO terms related to immune function, especially between F and P. Seven significantly enriched profiles were identified, among which 497 and 1261 DE mRNAs were upregulated in profiles 19 and 17. Eleven mRNAs were enriched in over 10 KEGG pathways. β-2-microglobulin (B2M), immunoglobulin heavy constant mu (IGHM), toll like receptor 2 (TLR2), toll like receptor 4 (TLR4) and myeloid differentiation factor 88 (MYD88) were mainly involved in phosphoinositide 3-kinase (PI3K)-Akt signalling, phagosome and nuclear factor kappa-B (NF-kappa B) signalling pathways. The findings provide insight into the molecular features underpinning the low prevalence of intramammary infections (i.e., mastitis) in donkeys.

Elucidation of the mechanism of Zhenbao pills for the treatment of spinal cord injury by network pharmacology and molecular docking: A review

To explore the mechanism of the Zhenbao pill (ZBP) in treating spinal cord injury (SCI). The TCMSP Database, HERB Database and literature search were used to screen the effective ingredients and targets of ZBP; SCI-related genes were searched in GeneCards, OMIM, PharmGkb, TTD and DrugBank databases; the potential targets of ZBP for treating SCI were predicted and Venn diagrams were drawn, and the "herb-ingredient-target" network was constructed by Cytoscape software. The PPI network was constructed by STRING software, and the core targets were screened by cytoNCA plug-in; GO enrichment and KEGG pathway analysis were performed on the predicted targets using the DAVID Platform, and visualized with the Microbiology Network Platform. The molecular docking between the key ingredients and the core target was carried out by AutoDockVina software. 391 active ingredients and 836 action targets were obtained from ZBP and there are 1557 SCI related genes in 5 disease databases. The top 5 active ingredients were Quercetin, Camptothecin, Kaempferol, Ethyl iso-allocholate, and Ethyl linoleate, and 5 core genes were SRC, CTNNB1, TP53, AKT1, and STAT3. GO enrichment analysis showed that the core targets were involved in 1206 biological processes, 120 cellular components and 160 molecular functions; KEGG enrichment analysis showed that the core targets involved 183 pathways, including PI3K-Akt signaling pathway and other signaling pathways. Molecular docking indicated that CTNNB1, SRC, TP53, AKT1 and STAT3 showed good binding ability with the active ingredients quercetin, kaempferol and ethyl isobutyric acid. ZBP improves SCI through multi-components, multi-targets and multi-pathways.

BPA and low-Se exacerbate apoptosis and mitophagy in chicken pancreatic cells by regulating the PTEN/PI3K/AKT/mTOR pathway

INTRODUCTION

Bisphenol A (BPA) is a widespread environmental pollutant which has serious toxic effects on organisms. One of the crucial trace elements is selenium (Se), whose shortage can harm biological tissues and enhance the toxicity of contaminants, in which apoptosis and autophagy are core events.

OBJECTIVES

An in vivo model was established to investigate the effects of BPA and low-Se on chicken pancreatic tissue, and identify the possible potential molecular mechanism.

METHODS

A total of 80 1-day-old broiler chickens (Xinghua Chicken Farm, Harbin, China) were stochastically divided into 4 groups (n = 20/group): Control group, BPA group, low-Se group, and low-Se + BPA group. Pancreatic tissue was collected at day 42 to detect changes in markers.

RESULTS

First, the data showed that BPA and low-Se exposure gave rose to structural abnormalities in pancreatic tissue, oxidative stress, mitochondrial dysfunction and homeostasis imbalance, apoptosis and mitophagy. In addition, the co-exposure of BPA and low-Se caused the most serious damage to pancreatic tissue. In terms of mechanism, it was found that apoptosis and mitophagy induced by BPA and low-Se were related to the activation of PTEN/PI3K/AKT/mTOR pathway.

CONCLUSION

In summary, the study found that BPA and low-Se exacerbated mitochondria damage, apoptosis and mitophagy by regulating the PTEN/PI3K/AKT/mTOR pathway.

Low vitamin D during pregnancy is associated with infantile eczema by up-regulation of PI3K/AKT/mTOR signaling pathway and affecting FOXP3 expression: A bidirectional cohort study

Vitamin D has received increasing attention because of its association with atopic disease development. Limited studies that have been done on the impact of maternal vitamin D levels during pregnancy on infantile eczema are still debatable. We wanted to discover the effect of maternal vitamin D on infantile eczema and explore whether regulatory T cells (Treg) play a role in this process. 219 pairs of mothers and children were enrolled. Maternal fasting venous blood was collected in pregnancy's second and third trimesters to determine vitamin D levels. Cord blood and placenta samples were collected during childbirth for detecting levels of genes, proteins and cytokines. Pediatricians followed up the prevalence of eczema in infants within 1 year. The reported rate of vitamin D deficiency and insufficiency was 35.6% and 28.3%. Lower maternal 25(OH)D3 levels were related to a higher risk of infantile eczema. Foxp3 gene expression is lower in cord blood of infants with eczema compared to infants without eczema. There was a positive correlation between maternal 25(OH)D3 levels and the expression of FOXP3 gene in cord blood. Compared to vitamin D sufficiency women, vitamin D deficiency women's placental FOXP3 protein expression was decreased and PI3K/AKT/mTOR protein was up-regulated. Our study demonstrates that low prenatal maternal vitamin D levels increased the risk of infantile eczema aged 0-1 year, which might be related to the downregulating of the FOXP3 gene expression in cord blood and decreased placental FOXP3 protein expression. Low placental FOXP3 protein was related with activating PI3K/AKT/mTOR signaling pathway.

The role of serum and glucocorticoid-regulated kinase 1 in cellular signaling: Implications for drug development

Serum and glucocorticoid-regulated kinase 1 (SGK1) is a ubiquitously expressed protein belonging to the Ser/Thr kinase family. It regulates diverse physiological processes, including epithelial sodium channel activity, hypertension, cell proliferation, and insulin sensitivity. Due to its significant role in the pathogenesis of numerous diseases, SGK1 can be exploited as a potential therapeutic target to address challenging health problems. SGK1 is associated with the development of obesity, and its overexpression enhances the sodium-glucose co-transporter 1 activity, which absorbs intestinal glucose. This review highlighted the detailed functional significance of SGK1 signaling and role in different diseases and subsequent therapeutic targeting. We aim to provide deeper mechanistic insights into understanding the pathogenesis and recent advancements in the SGK1 targeted drug development process. Small-molecule inhibitors are being developed with excellent binding affinity and improved SGK1 inhibition with desired selectivity. We have discussed small molecule inhibitors designed explicitly as potent SGK1 inhibitors and their therapeutic implications in various diseases. We further addressed the therapeutic potential and mechanism of action of these SGK1 inhibitors and provided a strong scientific foundation for developing effective therapeutics.

MIWE: detecting the critical states of complex biological systems by the mutual information weighted entropy

Complex biological systems often undergo sudden qualitative changes during their dynamic evolution. These critical transitions are typically characterized by a catastrophic progression of the system. Identifying the critical point is critical to uncovering the underlying mechanisms of complex biological systems. However, the system may exhibit minimal changes in its state until the critical point is reached, and in the face of high throughput and strong noise data, traditional biomarkers may not be effective in distinguishing the critical state. In this study, we propose a novel approach, mutual information weighted entropy (MIWE), which uses mutual information between genes to build networks and identifies critical states by quantifying molecular dynamic differences at each stage through weighted differential entropy. The method is applied to one numerical simulation dataset and four real datasets, including bulk and single-cell expression datasets. The critical states of the system can be recognized and the robustness of MIWE method is verified by numerical simulation under the influence of different noises. Moreover, we identify two key transcription factors (TFs), CREB1 and CREB3, that regulate downstream signaling genes to coordinate cell fate commitment. The dark genes in the single-cell expression datasets are mined to reveal the potential pathway regulation mechanism.

Novel lncRNA regulatory elements in milk somatic cells of Holstein dairy cows associated with mastitis

Despite regulatory elements such as long non - coding RNAs representing most of the transcriptome, the functional understanding of long non - coding RNAs in relation to major health conditions including bovine mastitis is limited. This study examined the milk somatic cell transcriptome from udder quarters of 6 Holstein dairy cows to identify differentially expressed long non - coding RNAs using RNA - Sequencing. Ninety - four differentially expressed long non - coding RNAs are identified, 5 of which are previously annotated for gene name and length, 11 are annotated for gene name and 78 are novel, having no gene name or length previously annotated. Significant inflammatory response and regulation of immune response pathways (false discovery rate < 0.05) are associated with the differentially expressed long non - coding RNAs. QTL annotation analysis revealed 31 QTL previously annotated in the genomic regions of the 94 differentially expressed long non - coding RNAs, and the majority are associated with milk traits. This research provides a better understanding of long non - coding RNAs regulatory elements in milk somatic cells, which may enhance current breeding strategies for more adaptable or high mastitis resistant cattle.

Predictive, preventive, and personalized medicine in breast cancer: targeting the PI3K pathway

Breast cancer (BC) is a multifaceted disease characterized by distinct molecular subtypes and varying responses to treatment. In BC, the phosphatidylinositol 3-kinase (PI3K) pathway has emerged as a crucial contributor to the development, advancement, and resistance to treatment. This review article explores the implications of the PI3K pathway in predictive, preventive, and personalized medicine for BC. It emphasizes the identification of predictive biomarkers, such as PIK3CA mutations, and the utility of molecular profiling in guiding treatment decisions. The review also discusses the potential of targeting the PI3K pathway for preventive strategies and the customization of therapy based on tumor stage, molecular subtypes, and genetic alterations. Overcoming resistance to PI3K inhibitors and exploring combination therapies are addressed as important considerations. While this field holds promise in improving patient outcomes, further research and clinical trials are needed to validate these approaches and translate them into clinical practice.

PI3K/Akt signaling pathway mediates the effect of low-dose boron on barrier function, proliferation and apoptosis in rat intestinal epithelial cells

Boron is an essential trace element with roles in growth, development, and physiological functions; however, its mechanism of action is still unclear. In this study, the regulatory roles of the PI3K/Akt signaling pathway on boron-induced changes in barrier function, proliferation, and apoptosis in rat intestinal epithelial cells were evaluated. Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein expression levels of PCNA were higher, while the proportions of cells in the G0/G1 and S phases, apoptosis rate, and caspase-3 mRNA and protein expression levels were lower in cells treated with 0.8 mmol/L boron than in control IEC-6 cells (P < 0.01 or P < 0.05). However, 40 mmol/L boron decreased ZO-1 and Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein levels of PCNA and increased the apoptosis rate and caspase-3 mRNA expression (P < 0.01 or P < 0.05). After specifically blocking PI3K and Akt signals (using LY294002 and MK-2206 2HCL), 0.8 mmol/L boron had no effects on Occludin, PCNA level, apoptosis rates, and caspase-3 levels (P < 0.05); however, the proliferation rate and PCNA levels decreased significantly (P < 0.01 or P < 0.05). The addition of 40 mmol/L boron did not affect ZO-1 and Occludin levels and did not affect the apoptosis rate or PCNA and caspase-3 levels. These results suggested that the PI3K/Akt signaling pathway mediates the effects of low-dose boron on IEC-6 cells.

The Potential Mechanism of Liujunzi Decoction in the Treatment of Breast Cancer based on Network Pharmacology and Molecular Docking Technology

BACKGROUND

Liujunzi Decoction (LJZD) is a potential clinical treatment for Breast Cancer (BC), but the active ingredients and mechanisms underlying its effectiveness remain unclear.

OBJECTIVE

The study aimed to investigate the target gene of LJZD compatibility and the possible mechanism of action in the treatment of breast cancer by using network pharmacology and molecular docking.

METHODS

Based on TCMSP, ETCM, and BATMAN database searching and screening to obtain the ingredients of LJZD, the related targets were obtained. Breast cancer-related targets were collected through GEO, Geencards, OMIM, and other databases, and drug-disease Venn diagrams were drawn by R. The PPI network map was constructed by using Cytoscape. The intersecting targets were imported into the STRING database, and the core targets were analyzed and screened. The intersected targets were analyzed by the DAVID database for GO and KEGG enrichment. AutoDock Vina and Gromacs were used for molecular docking and simulation of the core targets and active ingredients.

RESULTS

126 active ingredients of LJZD were obtained; 241 targets related to breast cancer were sought after screening, and 180 intersection targets were identified through Venn diagram analysis. The core targets were FOS and ESR1. KEGG enrichment analysis mainly involved PI3K/Akt, MAPK, and other signaling pathways.

CONCLUSION

This study has explored the possible targets and signaling pathways of LJZD in treating breast cancer through network pharmacology and bioinformatics analysis. Molecular docking and simulation have further validated the potential mechanism of action of LJZD in breast cancer treatment, providing essential experimental data for future studies.

Molecular Mechanisms of Medicinal Plant Securinega suffruticosa-derived Compound Securinine against Spinal Muscular Atrophy based on Network Pharmacology and Experimental Verification

BACKGROUND

Spinal Muscular Atrophy (SMA) is a severe motor neuronal disorder with high morbidity and mortality. Securinine has shown the potential to treat SMA; however, its anti-SMA role remains unclear.

OBJECTIVE

This study aims to reveal the anti-SMA mechanisms of securinine.

METHODS

Securinine-associated targets were acquired from Herbal Ingredients' Targets (HIT), Similarity Ensemble Approach (SEA), and SuperPred. SMA-associated targets were obtained from GeneCards and Dis- GeNET. Protein-protein Interaction (PPI) network was constructed using GeneMANIA, and hug targets were screened using cytoHubba. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using ClusterProfifiler. Molecular docking was conducted using Pymol and Auto- Dock. In vitro assays were used to verify the anti-SMA effects of securinine.

RESULTS

Twenty-six intersection targets of securinine and SMA were obtained. HDAC1, HDAC2, TOP2A, PIK3R1, PRMT5, JAK2, HSP90AB1, TERT, PTGS2, and PAX8 were the core targets in PPI network. GO analysis demonstrated that the intersecting targets were implicated in the regulation of proteins, steroid hormones, histone deacetylases, and DNA transcription. KEGG analysis, pathway-pathway, and hub target-pathway networks revealed that securinine might treat SMA through TNF, JAK-STAT, Ras, and PI3K-Akt pathways. Securinine had a favorable binding affinity with HDAC1, HSP90AB, JAK2, PRMT5, PTGS2, and TERT. Securinine rescued viability suppression, mitochondria damage, and SMN loss in the SMA cell model. Furthermore, securinine increased HDAC1 and PRMT5 expression, decreased PTGS2 expression, suppressed the JAK2-STAT3 pathway, and promoted the PI3K-Akt pathway.

CONCLUSION

Securinine might alleviate SMA by elevating HDAC1 and PRMT5 expression and reducing PTGS2 via JAK2-STAT3 suppression and PI3K-Akt activation.

Transcriptome profiling of regulatory T cells from children with transient hypogammaglobulinemia of infancy

Transient hypogammaglobulinemia of infancy (THI) is one of the most common forms of hypogammaglobulinemia in the early childhood. THI is usually associated with chronic, recurrent bacterial and viral infections, life-threatening in some cases, yet its pathogenesis is still largely unknown. As our previous findings indicated the possible role of Treg cells in the pathomechanism of THI, the aim of the current study was to investigate gene expression profile of Treg cells isolated from THI patients. The transcriptome-wide gene profiling was performed using microarray technology on THI patients in two time-points: during (THI-1), and in resolution phase (THI-2) of hypogammaglobulinemia. As a result, a total of 1086 genes were differentially expressed in THI-1 patients, when compared to THI-2 as well as control group. Among them, 931 were up- and 155 downregulated, and part of them encodes genes important for Treg lymphocyte biology and function, i.e. transcription factors/cofactors that regulate FOXP3 expression. Thus, we postulate that Treg cells isolated from THI patients during hypogammaglobulinemia display enhanced suppressor transcriptome signature. Treg expression profile of THI children after normalization of Ig levels largely resembles the results obtained in healthy control group, suggesting THI Treg transcriptome seems to return to that observed in healthy children. Taken together, we suggest that THI pathomechanism is associated not only with transiently elevated Treg cell numbers, but also with their enhanced regulatory/inhibitory functions. These findings expand our knowledge of human Treg cells and may be useful for the future diagnosis or management of THI.

TPN10475 alleviates concanavalin A-induced autoimmune hepatitis by limiting T cell development and function through inhibition of PI3K-AKT pathway

Autoimmune hepatitis (AIH) is an inflammatory liver disease in which the autoimmune system instigates an attack on the liver, causing inflammation and liver injury, and its incidence has increased worldwide in recent years. The mouse model of acute hepatitis established by concanavalin A (Con A) is a typical and recognized mouse model for the study of T-cell-dependent liver injury. In this study, we aimed to investigate whether the artemisinin derivative TPN10475 could alleviate AIH and its possible mechanisms. TPN10475 effectively inhibited lymphocyte proliferation and IFN-γ+ T cells production in vitro, alleviated liver injury by decreasing infiltrating inflammatory T cells producing IFN-γ in the liver and peripheral immune tissues, and demonstrated that TPN10475 weakened the activation and function of T cells by inhibiting PI3K-AKT signaling pathway. These results suggested that TPN10475 may be a potential drug for the treatment of AIH, and the inhibition of PI3K-AKT signaling pathway may provide new ideas for the study of the pathogenesis of AIH.

microRNA-944 inhibits breast cancer cell proliferation and promotes cell apoptosis by reducing SPP1 through inactivating the PI3K/Akt pathway

Breast cancer is a common malignancy in women with poor prognosis. This study aimed to investigate the molecular mechanism of microRNA-944 (miR-944) mediated secreted phosphoprotein-1 (SPP1) in breast cancer progression and its regulatory effect on the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway. Differential gene analysis was performed to identify key genes associated with breast cancer development by screening breast cancer-related microarray data. The expression of miR-944 and SPP1 and their relationship were determined in clinical samples and cells. sh-SPP1, oe-SPP1, LY294002 or miR-944 mimic were transfected into MCF-7 cells to investigate the role of miR-944 mediated SPP1 in breast cancer development and its regulatory effect on the PI3K/Akt pathway. Finally, the tumorigenicity of breast cancer cells was observed in nude mice. Through bioinformatics analysis, we identified SPP1 as a key gene in breast cancer, and miR-944 as an upstream miRNA of SPP1. In breast cancer tissues and cells, the expression of miR-944 was decreased while that of SPP1 was increased. miR-944 negatively regulated the expression of SPP1. In breast cancer cells, SPP1 activated the PI3K/Akt pathway to promote cell proliferation and inhibit apoptosis. In vitro cell experiments showed that the downregulation of miR-944 promoted the high expression of SPP1, which then activated the PI3K/Akt signaling pathway, promoting breast cancer cell proliferation. In vivo experiments further confirmed the anti-cancer role of miR-944 mediated SPP1 in breast cancer. Our study highlights the role of miR-944 mediated SPP1 in inhibiting breast cancer progression by blocking the PI3K/Akt pathway.

HMGB1/PTEN/PI3K axis participates in the peripheral immune cell differentiation in two representative TCM syndromes of chronic hepatitis B patients

Liver depression and spleen deficiency syndrome (LDSDS) and spleen-gastric damp-heat syndrome (SGDHS) are two major traditional Chinese medicine syndromes observed in chronic hepatitis B (CHB). Both syndromes exhibit significant differences in the pathogenesis and prognosis, and are closely related to the immune system. However, the underlying mechanisms are largely unknown. This study aimed to explore the immunoregulatory mechanisms of the two syndromes and promote the differentiation precision between the two syndromes. Thirty-six patients with CHB (18 LDSDS patients and 18 SGDHS patients) and 14 healthy controls were recruited into this study and blood was collected from all the subjects for testing. We studied the contents of T lymphocytes by flow cytometry and the expression levels of HMGB1/PTEN/PI3K axis proteins by enzyme-linked immunosorbent assay (Elisa). Protein-protein interaction (PPI) networks among HMGB1/PTEN/PI3K axis were constructed for functional enrichment. The correlations between T lymphocytes and proteins were analyzed by constructing multiple regression equations. The results revealed that the CD8+ T cells level in the two syndromes were lower than that in healthy controls, and the levels of Th17, Treg cells, and HMGB1, PI3K, PDK1, Akt were higher than those of the healthy controls (p < 0.05). Moreover, the levels of CD4+ T, Th17 cells, and HMGB1, PTEN, PI3K in LDSDS were higher than SGDHS (p < 0.05). PPI network indicated that HMGB1/PTEN/PI3K axis participated in T cell activation and liver pathology. Our results revealed that HMGB1/PTEN/PI3K axis may play an important role in regulating the formation of peripheral immune differences between the two syndromes. CD4+ T and Th17 are two representative immune cells that may serve as potential biological markers for LDSDS and SGDHS in CHB.

Polystyrene microplastics with different sizes induce the apoptosis and necroptosis in liver through the PTEN/PI3K/AKT/autophagy axis

The production of plastics worldwide has been instrumental in the progress of modern society, while the increasing accumulation of plastics castoff in oceans, soils and anywhere else has become a major pressure source on environmental sustainability and animal health. Meanwhile, from a biological perspective, our understanding of the toxicological fingerprints of plastics, especially microplastics (MPs), is still poor. Here, we reported a phenomenon of hepatotoxicity dominated by MPs in the form of polystyrene (PS), was observed in mice model systems and cellular assays. Apoptosis and necroptosis related to the size of particles were seen upon PS-MPs introduction, as revealed by transmission electron microscopy, fluorescence microscopy, flow cytometry, and quantitative analysis of signaling pathways in vivo and vitro. Collectively, the current study demonstrated that the levels of liver cell injury caused by PS-MPs were negatively correlated with the particle diameters. Small-sized particles (1-10 μm) induced cell death primarily as necroptosis whereas the large-sized particles (50-100 μm) mainly induced apoptosis, which was directly accomplished by PTEN/PI3K/AKT signaling axis and its targeted autophagy flux. More interestingly, inhibition of autophagy not only alleviated PS-MPs-triggered cell death, but also changed the form of death injury to a certain extent. This uncovered crosstalk relationship opens up a new avenue for investigating the biological and toxicological effects of MPs, and may provide important insights for preventing and limiting of health hazards from MPs.

Unleashing the pathological imprinting of cancer in autoimmunity: Is ZEB1 the answer?

The intriguing scientific relationship between autoimmunity and cancer immunology have been traditionally indulged to throw spotlight on novel pathological targets. Understandably, these "slowly killing" diseases are on the opposite ends of the immune spectrum. However, the immune regulatory mechanisms between autoimmunity and cancer are not always contradictory and sometimes mirror each other based on disease stage, location, and timepoint. Moreover, the blockade of immune checkpoint molecules or signalling pathways that unleashes the immune response against cancer is being leveraged to preserve self-tolerance and treat many autoimmune disorders. Therefore, understanding the common crucial factors involved in cancer is of paramount importance to paint the autoimmune disease spectrum and validate novel drug candidates. In the current review, we will broadly describe how ZEB1, or Zinc-finger E-box Binding Homeobox 1, reinforces immune exhaustion in cancer or contributes to loss of self-tolerance in auto-immune conditions. We made an effort to exchange information about the molecular pathways and pathological responses (immune regulation, cell proliferation, senescence, autophagy, hypoxia, and circadian rhythm) that can be regulated by ZEB1 in the context of autoimmunity. This will help untwine the intricate and closely postured pathogenesis of ZEB1, that is less explored from the perspective of autoimmunity than its counterpart, cancer. This review will further consider several approaches for targeting ZEB1 in autoimmunity.

1-Monopalmitin promotes lung cancer cells apoptosis through PI3K/Akt pathway in vitro

Lung cancer is the leading cause of cancer-related death worldwide and non-small cell lung cancer (NSCLC) represents 85%. Mougeotia nummuloides and Spirulina major have been reported to possess anticancer properties. 1-Monopalmitin (1-Mono) is the principle active constituent in these natural plants. It is debating whether 1-Mono exerts antitumor effects. Therefore, we explored the role of 1-Mono in lung cancer in vitro. Results showed that 1-Mono significantly inhibited A549 and SPC-A1 cell proliferation, induced G2/M arrest and caspase-dependent apoptosis. Moreover, it suppressed the protein expression of inhibitors of apoptosis proteins (IAPs). It was further demonstrated that 1-Mono activated the PI3K/Akt pathway, suppression of PI3K/Akt activities with LY294002 and Wortmannin partially attenuated 1-Mono-mediated anticancer activities, indicating that 1-Mono-induced antitumor effects is dependent on PI3K/Akt pathway. 1-Mono induced cytoprotective autophagy since autophagy inhibitor Chloroquine dramatically enhanced 1-Mono-induced cytotoxicity. In summary, our results showed 1-Mono kills lung cancer through PI3K/Akt pathway, providing novel options for lung cancer administration.

Transcriptomic analysis reveals differentially expressed genes and key immune pathways in the spleen of the yak (Bos grunniens) at different growth stage

Yak is one of the rare and unique cattle species on the Qinghai-Tibetan Plateau, which has strong adaptability to the extreme environment of the plateau. The spleens are important functional organs that enable animals to adapt to their external environment and are vital in the growth and development process. To further investigate changes in immune function during yak development, we compared the transcriptome profiles of spleen tissues among juvenile (1-day old), youth (15-months old), and prime (5-years old) yaks. Immunology of spleen development was evaluated based on histological analyses and global gene expression was examined by using RNA-sequencing (RNA-seq) technology. In this work, we found 6378 genes with significant differences between the spleen of juvenile yak and youth yak, with the largest difference between groups. There were 3144 genes with significant differences between the spleen of young yak and prime yak, with the smallest differences between groups. Further, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted for the functional annotation of these genes. GO and KEGG analysis showed that some of them were related to growth, disease, immune, and metabolism. However, the genetic mechanism underlying the adaptability of yak spleens at different ages to harsh plateau environments remains unknown. These findings are important for studying the mechanisms of spleen development in yaks of different age groups.

Therapeutic potential of bixin on inflammation: a mini review

Chronic inflammation is the underlying mechanism for many diseases. Thus, inflammatory signaling pathways are valuable targets for new treatment modalities. Natural products have gained interest as a potential source of bioactive compounds which provide health benefits in combating inflammatory-related diseases. Recent reports have linked the medicinal values of Bixa orellana L. with its anti-inflammatory activities. Therefore, this review aims to examine the therapeutic potential of bixin, a major bioactive constituent found in the seeds of B. orellana, on inflammatory-related diseases based on existing in vitro and in vivo evidence. Additionally, the anti-inflammatory mechanism of bixin via signaling pathways is explored and possible toxic effects are addressed. The findings suggest that bixin may ameliorate inflammation via inhibition of toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB), phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) and thioredoxin-interacting protein/NOD-like receptor protein 3 (TXNIP/NLRP3) inflammasome mechanisms. More well-planned clinical studies should be performed to verify its effectiveness and safety profile.

Prenatal exposure to crude oil vapor reduces differentiation potential of rat fetal mesenchymal stem cells by regulating ERK1/2 and PI3K signaling pathways: Protective effect of quercetin

It has been indicated that crude oil vapor (COV) induces tissue damage by several molecular mechanisms. Quercetin (QT) as an important component of food with antioxidant properties has a protective role against cell toxicity caused by many pollutants. However, data related to the adverse effects of crude oil vapor (COV) on stem cell fate and differentiation and the role of quercetin (QT) in protecting stem cells against the toxicity caused by these pollutants is very limited. This study aimed to explore the protective effect of QT against the adverse effects of COV on fetal mesenchymal stem cells (fMSCs) differentiation. Twenty-four pregnant Wistar rats were categorized into 4 groups including the control, COV, COV+QT, and QT. Rats were exposed to COV from gestational day (GD) 0-15 and received QT by gavage. The fMSCs were isolated from fetuses, and cell proliferation, differentiation potential, expression of osteogenesis and adipogenesis-related genes, and phosphorylation of PI3K and ERK1/2 signaling proteins were evaluated. The results showed that COV reduced the proliferation and differentiation of fMSCs through the activation of PI3K and ERK1/2 signaling pathways. Also, COV significantly decreased the expression of osteonectin, ALP, BMP-6, Runx-2, PPARγ, and CREBBP genes in differentiated cells. QT treatment increased the proliferation and differentiation of fMSCs in COV-exposed rats. In conclusion, our findings suggest that prenatal exposure to COV impaired fMSCs differentiation and QT reduced the adverse effects of COV by regulating ERK1/2 and PI3K signaling pathways.

PTPN22 activates the PI3K pathway via 14-3-3τ in T cells

The protein tyrosine phosphatase PTPN22 inhibits T cell activation by dephosphorylating some essential proteins in the T cell receptor-mediated signalling pathway, and its negative regulatory function protects organisms from autoimmune disease. 14-3-3τ is an adaptor protein that regulates target protein function through its intracellular localization. In the present study, we determined that PTPN22 binds to 14-3-3τ via the PTPN22-Ser640 phosphorylation side. PTPN22 binding to 14-3-3τ resulted in 14-3-3τ-Tyr179 dephosphorylation, and reduced the association between 14-3-3τ and Shc, which competitively increased 14-3-3ζ binding to Shc and activated phosphoinositide 3-kinase (PI3K) by bringing it to the membrane. In addition, PTPN22 decreased the tyrosine phosphorylation of p110 to activate PI3K. These two pathways cooperatively affect PI3K activity and the expression of PI3K downstream proteins, such as phosphorylated Akt, mammalian target of rapamycin and forkhead box O1, which inhibited the expression of some proinflammatory factors such as interleukin-1β, interleukin-2, interleukin-6, interferon-γ and tumour necrosis factor-α. Our research provides a preliminary theory for PTPN22 regulating T cell activation, development and immune response via the PI3K/Akt/mammalian target of rapamycin pathway and brings new information for clarifying the functions of PTPN22 in autoimmune diseases.

PI3K signaling-regulated metabolic reprogramming: From mechanism to application

Oncogenic signaling involved in tumor metabolic reprogramming. Tumorigenesis was not only determined by the mutations or deletion of oncogenes but also accompanied by the reprogramming of cellular metabolism. Metabolic alterations play a crucial regulatory role in the development and progression of tumors. Oncogenic PI3K/AKT signaling mediates the metabolic switch in cancer cells and immune cells in the tumor microenvironment. PI3K/AKT and its downstream effector branch off and connect to multiple steps of metabolism, such as glucose, lipids, and amino acids. Thus, PI3K inhibitor could effectively regulate metabolic pathway and impede the oncogenic process and some key metabolic proteins or critical enzymes also constitute biomarkers for tumor diagnosis and treatment. In the current review, we summarize the significant effect of PI3K/AKT signaling toward tumor metabolism, it enables us to obtain the better understanding for this interaction and develop more effective therapeutic strategies targeting cancer cell metabolism.

MiR-93-5p inhibits retinal neurons apoptosis by regulating PDCD4 in acute ocular hypertension model

The present study focused on the effect of miR-93-5p on apoptosis of retinal neurons in acute ocular hypertension (AOH) model by regulating PDCD4 and explored its related mechanism. We detected that miR-93-5p expression was decreased and PDCD4 expression was increased in the AOH retina by qRT-PCR. Therefore, we explored the role of miR-93-5p and PDCD4. MiR-93-5p overexpression inhibited the apoptosis of retinal neurons and the expression of PDCD4 in vivo and in vitro. Inhibiting the expression of PDCD4 via transfected interfering RNA decreased the apoptosis of retinal cells and increased the expression of PI3K/Akt pathway-related proteins in vitro. However, the addition of PI3K protein inhibitor LY294002 reversed this effect, leading to a decrease of PI3K/Akt pathway protein expression and an increase of apoptosis-related protein Bax/Bcl-2 expression ratio. Finally, up-regulating miR-93-5p or down-regulating PDCD4 increased the expression of PI3K/Akt pathway protein in vivo. In conclusion, under the condition of AOH injury, miR-93-5p-inhibiting PDCD4 expression reduced the apoptosis of retinal neurons by activating PI3K/Akt pathway.

Current understanding of CTLA-4: from mechanism to autoimmune diseases

Autoimmune diseases (ADs) are characterized by the production of autoreactive lymphocytes, immune responses to self-antigens, and inflammation in related tissues and organs. Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is majorly expressed in activated T cells and works as a critical regulator in the inflammatory response. In this review, we first describe the structure, expression, and how the signaling pathways of CTLA-4 participate in reducing effector T-cell activity and enhancing the immunomodulatory ability of regulatory T (Treg) cells to reduce immune response, maintain immune homeostasis, and maintain autoimmune silence. We then focused on the correlation between CTLA-4 and different ADs and how this molecule regulates the immune activity of the diseases and inhibits the onset, progression, and pathology of various ADs. Finally, we summarized the current progress of CTLA-4 as a therapeutic target for various ADs.

Network Pharmacology, Molecular Docking and Molecular Dynamics to Explore the Potential Immunomodulatory Mechanisms of Deer Antler

The use of deer antlers dates back thousands of years in Chinese history. Deer antlers have antitumor, anti-inflammatory, and immunomodulatory properties and can be used in treating neurological diseases. However, only a few studies have reported the immunomodulatory mechanism of deer antler active compounds. Using network pharmacology, molecular docking, and molecular dynamics simulation techniques, we analyzed the underlying mechanism by which deer antlers regulate the immune response. We identified 4 substances and 130 core targets that may play immunomodulatory roles, and the beneficial and non-beneficial effects in the process of immune regulation were analyzed. The targets were enriched in pathways related to cancer, human cytomegalovirus infection, the PI3K-Akt signaling pathway, human T cell leukemia virus 1 infection, and lipids and atherosclerosis. Molecular docking showed that AKT1, MAPK3, and SRC have good binding activity with 17 beta estradiol and estrone. Additionally, the molecular dynamics simulation of the molecular docking result using GROMACS software (version: 2021.2) was performed and we found that the AKT1-estrone complex, 17 beta estradiol-AKT1 complex, estrone-MAPK3 complex, and 17 beta estradiol-MAPK3 complex had relatively good binding stability. Our research sheds light on the immunomodulatory mechanism of deer antlers and provides a theoretical foundation for further exploration of their active compounds.

PD-L1's Role in Preventing Alloreactive T Cell Responses Following Hematopoietic and Organ Transplant

Over the past decade, Programmed Death-Ligand 1 (PD-L1) has emerged as a prominent target for cancer immunotherapies. However, its potential as an immunosuppressive therapy has been limited. In this review, we present the immunological basis of graft rejection and graft-versus-host disease (GVHD), followed by a summary of biologically relevant molecular interactions of both PD-L1 and Programmed Cell Death Protein 1 (PD-1). Finally, we present a translational perspective on how PD-L1 can interrupt alloreactive-driven processes to increase immune tolerance. Unlike most current therapies that block PD-L1 and/or its interaction with PD-1, this review focuses on how upregulation or reversed sequestration of this ligand may reduce autoimmunity, ameliorate GVHD, and enhance graft survival following organ transplant.

CXCL8 and the peritoneal metastasis of ovarian and gastric cancer

CXCL8 is the most representative chemokine produced autocrine or paracrine by tumor cells, endothelial cells and lymphocytes. It can play a key role in normal tissues and tumors by activating PI3K-Akt, PLC, JAK-STAT, and other signaling pathways after combining with CXCR1/2. The incidence of peritoneal metastasis in ovarian and gastric cancer is extremely high. The structure of the peritoneum and various peritoneal-related cells supports the peritoneal metastasis of cancers, which readily produces a poor prognosis, low 5-year survival rate, and the death of patients. Studies show that CXCL8 is excessively secreted in a variety of cancers. Thus, this paper will further elaborate on the mechanism of CXCL8 and the peritoneal metastasis of ovarian and gastric cancer to provide a theoretical basis for the proposal of new methods for the prevention, diagnosis, and treatment of cancer peritoneal metastasis.

The deacetylation of Akt by SIRT1 inhibits inflammation in macrophages and protects against sepsis

Sepsis is characterized by uncontrolled inflammatory response and altered polarization of macrophages at the early phase. Akt is known to drive macrophage inflammatory response. However, how macrophage inflammatory response is fine-tuned by Akt is poorly understood. Here, we found that Lys14 and Lys20 of Akt is deacetylated by the histone deacetylase SIRT1 during macrophage activation to suppress macrophages inflammatory response. Mechanistically, SIRT1 promotes Akt deacetylation to inhibit the activation of NF-κB and pro-inflammatory cytokines. Loss of SIRT1 facilitates Akt acetylation and thus promotes inflammatory cytokines in mouse macrophages, potentially worsen the progression of sepsis in mice. By contrast, the upregulation of SIRT1 in macrophages further contributes to the inhibition of pro-inflammatory cytokines via Akt activation in sepsis. Taken together, our findings establish Akt deacetylation as an essential negative regulatory mechanism that curtails M1 polarization.

Spatiotemporal Coordination of RPE Cell Quality by Extracellular Vesicle miR-494-3p Via Competitive Interplays With SIRT3 or PTEN

Purpose

To reveal the molecular mechanism underlying degeneration in human retinal pigment epithelial (hRPE) cells with dysfunctional mitochondrial homeostasis.

Methods

The expression of recently identified miR-494-3p in extracellular vesicles (EV) released from induced-pluripotential-stem-cell-derived human RPE (iPS-hRPE), during coculture with macrophages (Mps) was investigated in iPS-hRPE and ARPE cells differentiated in the presence of nicotinamide (Nic-ARPE). The expression of phosphatase and tensin homolog (PTEN), sirtuin3 (SIRT3), and mitochondrial marker proteins before and after the transfection of miR-494-3p inhibitor and mimic, and the changes in mitochondrial metabolism, membrane potential, and oxidative phosphorylation (OXPHOS) were monitored.

Results

Compared with senescent dedifferentiated ARPE19 cells, iPS-hRPE and Nic-ARPE cells expressed elevated levels of mitochondrial marker proteins but a repressed cellular miR-494-3p level. The expression of target proteins of miR-494-3p, PTEN, and SIRT3 was upregulated along with the differentiation disposition of these RPE cells. The ratio of PTEN/SIRT3 in de-differentiated ARPE19 cells was surprisingly elevated by around 20 times compared with that in iPS-hRPE and Nic-ARPE cells. The novel molecular interplay of EV miR-494-3p either with mitochondria selective SIRT3 or organelle nonselective PTEN was found to participate in the degeneration of hRPE cells by inducing mitochondrial dysfunctions and repressed OXPHOS, mitochondrial membrane potential, and ATP and NAD+ production.

Conclusions

Our results demonstrate a clear causal link between miR-494-3p and hRPE cell degeneration via the regulation of mitochondrial integrity. EV miR-494-3p may play a pivotal role in pathogenic spreading of degenerated hRPE cells from the local perifovea throughout the macula.

MUC1 induces the accumulation of Foxp3+ Treg cells in the tumor microenvironment to promote the growth and metastasis of cholangiocarcinoma through the EGFR/PI3K/Akt signaling pathway

Tumor microenvironment (TME) plays an important role in the progression of cholangiocarcinoma. This study aims to explore whether Mucin 1 (MUC1) regulates Foxp3⁺ Treg cells in the TME of cholangiocarcinoma through the epidermal growth factor receptor (EGFR)/phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathway. High-throughput sequencing dataset in the GEO database combined with GeneCards and Phenolyzer databases was used to obtain key genes in cholangiocarcinoma, followed by downstream pathway prediction. The relationship among MUC1, EGFR, and PI3K/Akt signaling pathway was explored. CD4⁺ T cells extracted from peripheral blood were induced to differentiate into Treg cells, followed by co-culture with cholangiocarcinoma cells. A mouse model was constructed to detect the role of MUC1 in the accumulation of Foxp3⁺ Treg cells, malignant phenotypes of cholangiocarcinoma, and tumorigenesis in vivo. MUC1, highly expressed in cholangiocarcinoma, might be involved in cholangiocarcinoma development. MUC1 interacted with the EGFR to activate the EGFR/PI3K/Akt signaling pathway. MUC1 overexpression could activate the EGFR/PI3K/Akt signaling pathway, which promoted the accumulation of Foxp3⁺ Treg cells in the TME and the malignant phenotypes of cholangiocarcinoma cells both in vitro and in vivo and enhanced tumorigenesis in vivo. MUC1 may interact with EGFR to activate the EGFR/PI3K/Akt signaling pathway, which induces the accumulation of Foxp3⁺ Treg cells, enhancing the malignant phenotypes of cholangiocarcinoma cells and tumorigenesis in vivo and ultimately augmenting cholangiocarcinoma growth and metastasis.

JI017 Induces Cell Autophagy and Apoptosis via Elevated Levels of Reactive Oxygen Species in Human Lung Cancer Cells

Lung cancer is one of the most common malignant tumors and a leading cause of cancer-related death in the worldwide. Various anticancer drugs, such as cisplatin and pemetrexed, have been developed for lung cancer treatment but due their drug resistance and side effects, novel treatments need to be developed. In this study, the efficacy of the natural drug JI017, which is known to have few side effects, was tested in lung cancer cells. JI017 inhibited A549, H460, and H1299 cell proliferation. JI017 induced apoptosis, regulated apoptotic molecules, and inhibited colony formation. Additionally, JI017 increased intracellular ROS generation. JI017 downregulated PI3K, AKT, and mTOR expression. JI017 increased the cytosolic accumulation of LC3. We found that JI017 promoted apoptosis through ROS-induced autophagy. Additionally, the xenograft tumor size was smaller in JI017-treated mice. We found that JI017 treatment increased MDA concentrations, decreased Ki-67 protein levels, and increased cleaved caspase-3 and LC3 levels in vivo. JI017 decreased cell proliferation and increased apoptosis by inducing autophagy signaling in H460 and H1299 lung cancer cells. Targeting JI017 and autophagy signaling could be useful in lung cancer treatment.

Liraglutide Attenuates Myocardial Ischemia/Reperfusion Injury Through the Inhibition of Necroptosis by Activating GLP-1R/PI3K/Akt Pathway

Necroptosis is a crucial programmed cell death that is tightly associated with myocardial ischemia/reperfusion injury (MI/RI). Liraglutide is an effective option for the treatment of type 2 diabetes and has recently been reported to exert cardioprotective effects on MI/RI. Researchers do not know whether the cardioprotective effect of liraglutide is involved in regulating necroptosis. This study aimed to explore the effect of liraglutide on MI/RI-induced necroptosis and its potential mechanisms. Hypoxia/reoxygenation (H/R) was performed on H9c2 cells in vitro to simulate ischemia/reperfusion (I/R) injury, and an MI/RI rat model was established in vivo by ligating the anterior descending branch of the left coronary artery. H/R or I/R damage was assessed by performing biochemical assay, Hoechst 33342/PI staining, H&E (hematoxylin and eosin) staining, and Annexin-V/PI staining. Our data revealed that liraglutide resulted in markedly increased cell viability and reduced cardiac enzyme release by protecting cardiomyocytes from a necrosis-like phenotype after H/R. The myocardial infarct size and cardiac enzyme release were reduced in the heart tissues from the liraglutide-treated group. The levels of necroptosis-associated proteins (receptor-interacting protein kinase 3 (RIPK3), p-RIPK3, and phosphorylated-mixed lineage kinase domain-like protein (p-MLKL)) were also reduced by the liraglutide treatment. Mechanistically, we revealed that liraglutide exerted cardioprotective effects through a glucagon-like peptide-1 receptor (GLP-1R) and phosphatidylinositol-3 kinase (PI3K)-dependent pathway. Both the GLP-1R inhibitor exendin (9-39) and the PI3K inhibitor LY294002 abrogated the protective effects of liraglutide in vitro. We found that liraglutide may attenuate MI/RI by inhibiting necroptosis, in part by enhancing the activity of the GLP-1R/PI3K/Akt pathway.

Treg-specific deletion of the phosphatase SHP-1 impairs control of inflammation in vivo

Introduction

To achieve a healthy and functional immune system, a delicate balance exists between the activation of conventional T cells (Tcon cells) and the suppression by regulatory T cells (Treg). The tyrosine phosphatase SHP-1, a negative regulator of TCR signaling, shapes this ‘activation-suppression’ balance by modulating Tcon cell resistance to Treg-mediated suppression. Treg cells also express SHP-1, but its role in influencing Treg function is still not fully understood.

Methods

We generated a Treg-specific SHP-1 deletion model, Foxp3Cre+ Shp-1f/f, to address how SHP-1 affects Treg function and thereby contributes to T cell homeostasis using a combination of ex vivo studies and in vivo models of inflammation and autoimmunity.

Results

We show that SHP-1 modulates Treg suppressive function at different levels. First, at the intracellular signaling level in Treg cells, SHP-1 attenuates TCR-dependent Akt phosphorylation, with loss of SHP-1 driving Treg cells towards a glycolysis pathway. At the functional level, SHP-1 expression limits the in vivo accumulation of CD44hiCD62Llo T cells within the steady state Tcon populations (both CD8+ as well as CD4+ Tcon). Further, SHP-1-deficient Treg cells are less efficient in suppressing inflammation in vivo; mechanistically, this appears to be due to a failure to survive or a defect in migration of SHP-1-deficient Treg cells to peripheral inflammation sites.

Conclusion

Our data identify SHP-1 as an important intracellular mediator for fine-tuning the balance between Treg-mediated suppression and Tcon activation/resistance.

Pgp3 protein of Chlamydia trachomatis inhibits apoptosis via HO-1 upregulation mediated by PI3K/Akt activation

As an obligate intracellular pathogen, Chlamydia trachomatis assumes various strategies to inhibit host cells apoptosis, thereby providing a suitable intracellular environment to ensure completion of the development cycle. In the current study, we revealed that Pgp3 protein, one of eight plasmid proteins of C. trachomatis that has been illustrated as the key virulence factor, increased HO-1 expression to suppress apoptosis, and downregulation of HO-1 with siRNA-HO-1 failed to exert anti-apoptosis activity of Pgp3 protein. Moreover, treatment of PI3K/Akt pathway inhibitor and Nrf2 inhibitor evidently reduced HO-1 expression and Nrf2 nuclear translocation was blocked by PI3K/Akt pathway inhibitor. These findings highlight that induction of HO-1 expression by Pgp3 protein is probably due to regulation of Nrf2 nuclear translocation activated by PI3K/Akt pathway, which provide clues on how C. trachomatis adjusts apoptosis.

Scoping Review on Epigenetic Mechanisms in Primary Immune Thrombocytopenia

Immune Thrombocytopenia (ITP) is an autoimmune blood disorder that involves multiple pathways responsible for the homeostasis of the immune system. Numerous pieces of literature have proposed the potential of immune-related genes as diagnostic and prognostic biomarkers, which mostly implicate the role of B cells and T cells in the pathogenesis of ITP. However, a more in-depth understanding is required of how these immune-related genes are regulated. Thus, this scoping review aims to collate evidence and further elucidate each possible epigenetics mechanism in the regulation of immunological pathways pertinent to the pathogenesis of ITP. This encompasses DNA methylation, histone modification, and non-coding RNA. A total of 41 studies were scrutinized to further clarify how each of the epigenetics mechanisms is related to the pathogenesis of ITP. Identifying epigenetics mechanisms will provide a new paradigm that may assist in the diagnosis and treatment of immune thrombocytopenia.

Comprehensive analysis of prognosis and immune function of CD70-CD27 signaling axis in pan-cancer

The immune checkpoint molecule CD70 and its receptor CD27 constitute the signal transduction axis, which is abnormally expressed in many solid tumors and is crucial for T cell co-stimulation and immune escape. Tumor cells regulate CD27 expression in the tumor microenvironment by expressing CD70, which promotes immune escape. Although current research evidence suggests a link between CD70 and tumors, no pan-cancer analysis is available. Using the Cancer Genome Atlas, Gene Expression Omnibus datasets, and online databases, we first explored the potential carcinogenic role of the CD70-CD27 signaling axis in human malignancies. Furthermore, qRT-PCR, Western blot, immunohistochemistry, and a T cell-mediated tumor cell killing assay were used to assess the biological function of the CD70-CD27 signaling axis. CD70 expression is upregulated in most cancers and has an obvious correlation with the prognosis of tumor patients. The expression of CD70 and CD27 is associated with the level of regulatory T cell (Treg) infiltration. In addition, T cell receptor signaling pathways, PI3K-AKT, NF-κB, and TNF signaling pathways are also involved in CD70-mediated immune escape. CD70 mainly regulates tumor immune escape by regulating T cell-mediated tumor killing, with Tregs possibly being its primary T cell subset. Our first pan-cancer study provides a relatively comprehensive understanding of the carcinogenic role of the CD70-CD27 signaling axis in different tumors.

Uncovering the effects and molecular mechanism of Astragalus membranaceus (Fisch.) Bunge and its bioactive ingredients formononetin and calycosin against colon cancer: An integrated approach based on network pharmacology analysis coupled with experimental validation and molecular docking

Colon cancer is a highly malignant cancer with poor prognosis. Astragalus membranaceus (Fisch.) Bunge (Huang Qi in Chinese, HQ), a well-known Chinese herbal medicine and a popular food additive, possesses various biological functions and has been frequently used for clinical treatment of colon cancer. However, the underlying mechanism is not fully understood. Isoflavonoids, including formononetin (FMNT) and calycosin (CS), are the main bioactive ingredients isolated from HQ. Thus, this study aimed to explore the inhibitory effects and mechanism of HQ, FMNT and CS against colon cancer by using network pharmacology coupled with experimental validation and molecular docking. The network pharmacology analysis revealed that FMNT and CS exerted their anticarcinogenic actions against colon cancer by regulating multiple signaling molecules and pathways, including MAPK and PI3K-Akt signaling pathways. The experimental validation data showed that HQ, FMNT and CS significantly suppressed the viability and proliferation, and promoted the apoptosis in colon cancer Caco2 and HT-29 cells. HQ, FMNT and CS also markedly inhibited the migration of Caco2 and HT-29 cells, accompanied by a marked increase in E-cadherin expression, and a notable decrease in N-cadherin and Vimentin expression. In addition, HQ, FMNT and CS strikingly decreased the expression of ERK1/2 phosphorylation (p-ERK1/2) without marked change in total ERK1/2 expression. They also slightly downregulated the p-Akt expression without significant alteration in total Akt expression. Pearson correlation analysis showed a significant positive correlation between the inactivation of ERK1/2 signaling pathway and the HQ, FMNT and CS-induced suppression of colon cancer. The molecular docking results indicated that FMNT and CS had a strong binding affinity for the key molecules of ERK1/2 signaling pathway. Conclusively, HQ, FMNT and CS exerted good therapeutic effects against colon cancer by mainly inhibiting the ERK1/2 signaling pathway, suggesting that HQ, FMNT and CS could be useful supplements that may enhance chemotherapeutic outcomes and benefit colon cancer patients.

Alternative splicing of FKBP5 gene exerts control over T lymphocyte expansion

FKBP51 is constitutively expressed by immune cells. As other FKBP family members, FKBP51 acts as a coreceptor for the natural products FK506 and rapamycin, which exhibit immunosuppressive effects. However, little is known about the intrinsic role of this large FKBP in the primary function of lymphocytes, that is, the adaptive immune response against foreign antigens, for example, pathogens. This paper aimed to investigate whether FKBP51 expression was modulated during lymphocyte activation. Moreover, as we recently identified a splicing isoform of FKBP51, namely FKBP51s, we also measured this splice protein, along with the canonical one, at different times of a peripheral blood mononuclear cell culture stimulated via T cell receptor. Our results show that the two FKBP51 isoforms were alternatively induced during the proliferative burst. Canonical FKBP51 increased in the time window between 48 and 96 h and its expression levels correlated with cyclin D levels. FKBP51s transiently increased earlier, at 24-36 h to reappearing later, at 120 h, when cyclin D expression returned at resting levels and proliferation ceased. Interestingly, within these two specific timeframes, FKBP51s accumulated in the nucleus. Here FKBP51s colocalized with the Foxp3 transcription factor at 36 h. Regulatory T cell (Treg) counts significantly decreased when FKBP51s was downmodulated. The coculture suppression assay suggested that FKBP51s supports the suppressive capability of Tregs. At 120 h, chromatin immunoprecipitation experiments found FKBP51s linked to CCND1 gene, suggesting a possible effect on gene transcription regulation, as previously demonstrated in melanoma. In conclusion, our study shows that FKBP5 isoforms are upregulated during lymphocyte activation, albeit on different timeframes. The activation of canonical FKBP51 coincides with proliferation hallmarks; FKBP5 splicing occurs early to sustain Treg development and late when proliferation ceases.

Regulatory T cell and macrophage crosstalk in acute lung injury: future perspectives

Acute lung injury (ALI) describes the injury to endothelial cells in the lungs and associated vessels due to various factors. Furthermore, ALI accompanied by inflammation and thrombosis has been reported as a common complication of SARS-COV-2 infection. It is widely accepted that inflammation and the cytokine storm are main causes of ALI. Two classical anti-inflammatory cell types, regulatory T cells (Tregs) and M2 macrophages, are theoretically capable of resisting uncontrolled inflammation. Recent studies have indicated possible crosstalk between Tregs and macrophages involving their mutual activation. In this review, we discuss the current findings related to ALI pathogenesis and the role of Tregs and macrophages. In particular, we review the molecular mechanisms underlying the crosstalk between Tregs and macrophages in ALI pathogenesis. Understanding the role of Tregs and macrophages will provide the potential targets for treating ALI.

Protective Effects of Chestnut (Castanea crenata) Inner Shell Extract in Macrophage-Driven Emphysematous Lesion Induced by Cigarette Smoke Condensate

Chestnut (Castanea crenata) inner shell extract (CIE), a curative herb in Korea, has diverse pharmacological effects against various diseases including pulmonary fibrosis, asthma, and chronic obstructive pulmonary disease (COPD). However, its molecular mechanisms of anti-emphysematous effects are still not fully elucidated. In the present study, we elucidate the efficacy of CIE against emphysematous lesion progression in a cigarette smoke condensate (CSC)-instilled mice and CSC-stimulated H292 cell line. The mice are administered CSC via intranasal instillation at 7-day intervals for 1 month after 1 week of pretreatment with CIE. CIE (100 or 300 mg/kg) is administered by oral gavage for 1 month. CIE decreased the macrophage count in bronchoalveolar lavage fluid and the severity of emphysematous lesions in lung tissue. Additionally, CIE suppressed the phosphatidylinositol 3-kinase/protein kinase B/nuclear factor kappa B signal pathway and thereby downregulated matrix metalloprotease-9 expression, which was confirmed in CSC-stimulated H292 cells. Thus, CIE effectively inhibited CSC-induced macrophage-driven emphysema progression in airways; this inhibition was associated with the suppression of protease-antiprotease imbalance. Our results propose that CIE has the potential for the alleviation of COPD.