Akt isoforms in the immune system

Chlorogenic acid alleviates DNCB-induced atopic dermatitis by inhibiting the Akt1/NF-κB signaling pathway

OBJECTIVE

Atopic dermatitis (AD) is a prevalent chronic inflammatory skin disease that significantly impacts patients' quality of life. Chlorogenic acid (CGA), a polyphenol present in various dietary sources and plants, has been shown to reduce skin inflammation. However, its efficacy and mechanisms of action in AD have not been thoroughly investigated. This study aimed to evaluate the therapeutic effect of CGA on AD in mice and explored its mechanism.

METHODS

To establish a BALB/c mouse model of AD induced by 2,4-dinitrochlorobenzene (DNCB) to evaluate the therapeutic potential of CGA. The anti-inflammatory effects of CGA were assessed by measuring IL-1β and IL-6 levels in TNF-α-stimulated HaCaT cells. The phosphorylation levels of PI3K, Akt, Akt1, NF-κB, and IκB-α were analyzed using Western blotting. Molecular docking was conducted to evaluate the binding affinity of CGA to Akt1.

RESULTS

Topical application of CGA significantly reduced dermatitis scores, spleen index, epidermal thickness, mast cell infiltration, and skin fibrosis. CGA reversed DNCB-induced increases in IgE, histamine, TNF-α, IL-1β, IL-6, and IL-8 levels. Western blot analysis showed that CGA inhibited the PI3K/Akt and NF-κB signaling pathways. In vitro, CGA exerts its anti-inflammatory effects by inhibiting the Akt1/NF-κB pathway, and the Akt activator (SC79) can counteract this effect. Molecular docking and dynamics simulations suggest that CGA may inhibit Akt1 activity by interacting with specific residues (ALA-50, GLY-37, TYR-326, ASP-323).

CONCLUSIONS

CGA improves AD by inhibiting the Akt1/NF-κB pathway, suggesting its potential as a natural treatment for AD.

Checkpoint kinase Wee1 activation drives inflammation and hypertrophy through the protein kinase B/phosphoinositide 3-kinases-nuclear factor κB pathway in cardiomyocytes

BACKGROUND AND AIMS

Hypertensive heart failure has an urgent need for new therapeutic targets. Protein kinases act as key regulators in cellular actions relevant to cardiac pathophysiology. This study identified a protein kinase, Wee1 G2 checkpoint kinase (Wee1), being activated and involved in this disease.

METHODS

RNA-seq-based kinase enrichment analysis was used to identify the involved kinase pathways. Cardiomyocyte-specific Wee1-deficiency mice with chronic angiotensin II (Ang II) infusion and transverse aortic constriction (TAC) were utilized to develop cardiac remodelling. RNA-seq and co-immunoprecipitation were used to explore the mechanism and substrate of Wee1.

RESULTS

Kinase enrichment analysis and experimental evidence revealed that Wee1 phosphorylation at Ser642, but not increased expression, was observed in hypertrophic cardiac tissues from both mice and human patients. Knockdown, pharmacological inhibition, or mutational inactivation of Wee1 significantly alleviated Ang II-induced cardiomyocyte injuries. RNA-seq analysis showed that phosphoinositide 3-kinases/protein kinase B (AKT) pathway mediated the function of Wee1 in cardiomyocytes. Mechanistically, the phosphorylated Wee1 directly binds to the PHD domain of AKT to phosphorylate AKT inducing AKT/phosphoinositide 3-kinases-nuclear factor κB signalling pathway activation and subsequent inflammation and hypertrophy in cardiomyocytes. Cardiomyocyte-specific Wee1 deficiency was found to protect against cardiac inflammation, remodelling, and dysfunction in mice subjected to transverse aortic constriction or Ang II infusion. Pharmacological Wee1 inhibition also attenuated Ang II-induced cardiac remodelling in mice.

CONCLUSIONS

Cardiomyocyte Wee1 activation drives inflammation and hypertrophy by directly phosphorylating AKT and activating AKT-nuclear factor κB pathway. This study identifies Wee1 as a new upstream kinase of AKT and a potential therapeutic target for hypertensive heart failure.

Differential regulation of calcium-NFAT signaling pathway by Akt isoforms: unraveling effector dynamics and exhaustion of cytotoxic T lymphocytes in tumor microenvironment

BACKGROUND

Impairment of Akt signaling has been observed in antigen-specific cytotoxic T lymphocytes (CTLs) during chronic viral infections or tumor progression. Despite numerous studies emphasizing Akt's role in driving CTL effector functions, there is limited exploration of using Akt molecules in T-cell engineering to enhance their antiviral or antitumor capabilities for therapeutic purposes. Some studies even conclude that inhibiting Akt activation during the in vitro expansion process can prevent T-cell exhaustion and boost the antitumor effector functions of chimeric antigen receptor-T cells in vivo. Given the unique expression patterns and functions of the three Akt isoforms in immune cells, we proposed that Akt isoforms in CTLs may regulate effector functions and T-cell exhaustion distinctly.

METHODS

In this study, we genetically modified tumor/virus-antigen-specific T-cell receptor tg CTLs to ectopically express Akt isoforms via retroviral transduction. We subsequently conducted western blotting, flow cytometry, and RNA sequencing analysis to assess their Akt expression, expression of immune checkpoints, antitumor/antivirus functionalities, and transcriptome. Additionally, we employed a persistent Hepatitis B Virus mouse model and a syngeneic hepatocellular carcinoma mouse model for further evaluation of their antivirus/antitumor efficacies.

RESULTS

We found that both Akt1 and Akt2 overexpression enhanced the cytotoxic capabilities of mouse CTLs, although with different dynamics. Specifically, Akt2 signaling in CTLs accelerated effector functions, leading to a rapid attack on tumor cells. Conversely, Akt1 signaling triggered calcium influx and subsequent nuclear factor of activated T cells (NFAT) activation, while Akt2 signaling suppressed calcium influx, preventing excessive NFAT expression and nuclear translocation. This repression of NFAT transcriptional activity by Akt2 signaling during prolonged antigen stimulation subsequently led to reduced expression of transcription factors associated with T-cell exhaustion, such as Egr2, Nr4a, Tox, and immune checkpoints. Consequently, Akt2-overexpressed CTLs displayed reduced T-cell exhaustion within the tumor microenvironment and efficiently eradicated tumors.

CONCLUSION

These findings highlight the essential role of Akt signaling in enabling tumor-specific CTLs to eliminate cancer cells in the solid TME, with Akt isoforms differentially regulating the calcium-calcineurin-NFAT signaling pathway. This discovery suggests the potential of AKT2 in T-cell engineering technology to enhance the survival and effector functions of adoptively transferred T cells for treating liver malignancies or chronic viral infections.

Targeting the PI3K/AKT/mTOR pathway in lung cancer: mechanisms and therapeutic targeting

Owing to its high mortality rate, lung cancer (LC) remains the most common cancer worldwide, with the highest malignancy diagnosis rate. The phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling (PAM) pathway is a critical intracellular pathway involved in various cellular functions and regulates numerous cellular processes, including growth, survival, proliferation, metabolism, apoptosis, invasion, and angiogenesis. This review aims to highlight preclinical and clinical studies focusing on the PAM signaling pathway in LC and underscore the potential of natural products targeting it. Additionally, this review synthesizes the existing literature and discusses combination therapy and future directions for LC treatment while acknowledging the ongoing challenges in the field. Continuous development of novel therapeutic agents, technologies, and precision medicine offers an increasingly optimistic outlook for the treatment of LC.

Perilla frutescens leaf extracts alleviate acute lung injury in mice by inhibiting KAT2A

ETHNOPHARMACOLOGICAL RELEVANCE

Acute lung injury (ALI) can lead to respiratory failure and even death. KAT2A is a key target to suppress the development of inflammation. A herb, perilla frutescens, is an effective treatment for pulmonary inflammatory diseases with anti-inflammatory effects; however, its mechanism of action remains unclear.

AIM OF THE STUDY

The purpose of this study was to investigate the therapeutic effect and underlying mechanism of perilla frutescens leaf extracts (PLE), in the treatment of ALI by focusing on its ability to treat inflammation.

MATERIALS AND METHODS

In vivo and in vitro models of ALI induced by LPS. Respiratory function, histopathological changes of lung, and BEAS-2B cells damage were assessed upon PLE. This effect is also tested under conditions of KAT2A over expression and KAT2A silencing.

RESULTS

PLE significantly attenuated LPS-induced histopathological changes in the lungs, improved respiratory function, and increased survival rate from LPS stimuation background in mice. PLE remarkably suppressed the phosphorylation of STAT3, AKT, ERK (1/2) and the release of cytokines (IL-6, TNF-α, and IL-1β) induced by LPS via inhibiting the expression of KAT2A.

CONCLUSIONS

PLE has a dose-dependent anti-inflammatory effect by inhibiting KAT2A expression to suppress LPS-induced ALI n mice. Our study expands the clinical indications of the traditional medicine PLE and provide a theoretical basis for clinical use of acute lung injury.

The evolution of small-molecule Akt inhibitors from hit to clinical candidate

Akt, a key regulator of cell survival, proliferation, and metabolism, has become a prominent target for treatment of cancer and inflammatory diseases. The journey of small-molecule Akt inhibitors from discovery to the clinic has faced numerous challenges, with a significant emphasis on optimization throughout the development process. Early discovery efforts identified various classes of inhibitors, including ATP-competitive and allosteric modulators. However, during preclinical and clinical development, several issues arose, including poor specificity, limited bioavailability, and toxicity. Optimization efforts have been central to overcoming these hurdles. Researchers focused on enhancing the selectivity of inhibitors to target Akt isoforms more precisely, reducing off-target effects, and improving pharmacokinetic properties to ensure better bioavailability and distribution. Structural modifications and the design of prodrugs have played a crucial role in refining the efficacy and safety profile of these inhibitors. Additionally, efforts have been made to optimize the therapeutic window, balancing effective dosing with minimal adverse effects. The review highlights how these optimization strategies have been key in advancing small-molecule Akt inhibitors toward clinical success and underscores the importance of continued refinement in their development.

Effect of particle size on dissolution of different chemical components in Codonopsis pilosula

Codonopsis pilosula (Franch.) Nannf. is a traditional herb for treating immunosuppression. C. pilosula boiling powder (CP-BP) contains particles of a small size made from C. pilosula decoction pieces (CP-DP). It is still unclear how changes in particle size during the decoction process affect the dissolution of various chemical components in C. pilosula. Herein, an ultra-high-performance liquid chromatography-quadrupole-Exactive Orbitrap mass spectrometry technique was established to characterize the components of CP-BP and CP-DP decoctions. The contents of the components were evaluated based on the relative peak area, extract yield, and alcohol solubility rate. A total of 71 compounds were finally identified, and their content in the CP-BP decoction was generally higher than that in the CP-DP decoction. Alkaloids had the highest average content, whereas terpenoids were the most affected by changes in particle size. In addition, immunosuppression was used as model to investigate whether these changes have practical significance. The results of network pharmacology suggested that the phosphoinositide 3-kinase (PI3K)-Akt pathway may be a potential pathway of C. pilosula for treating immunosuppression. The results of molecular docking indicated that compounds with large content variations have good docking affinity with key targets (epidermal growth factor receptor [EGFR], prostaglandin-endoperoxide synthase 2 [PTGS2], and peroxisome proliferator-activated receptor gamma [PPARG]). These results provide an important reference for further development and use of C. pilosula.

VPS34 Governs Oocyte Developmental Competence by Regulating Mito/Autophagy: A Novel Insight into the Significance of RAB7 Activity and Its Subcellular Location

Asynchronous nuclear and cytoplasmic maturation in human oocytes is believed to cause morphological anomalies after controlled ovarian hyperstimulation. Vacuolar protein sorting 34 (VPS34) is renowned for its pivotal role in regulating autophagy and endocytic trafficking. To investigate its impact on oocyte development, oocyte-specific knockout mice (ZcKO) are generated, and these mice are completely found infertile, with embryonic development halted at 2- to 4-cell stage. This infertility is related with a disruption on autophagic/mitophagic flux in ZcKO oocytes, leading to subsequent failure of zygotic genome activation (ZGA) in derived 2-cell embryos. The findings further elucidated the regulation of VPS34 on the activity and subcellular translocation of RAS-related GTP-binding protein 7 (RAB7), which is critical not only for the maturation of late endosomes and lysosomes, but also for initiating mitophagy via retrograde trafficking. VPS34 binds directly with RAB7 and facilitates its activity conversion through TBC1 domain family member 5 (TBC1D5). Consistent with the cytoplasmic vacuolation observed in ZcKO oocytes, defects in multiple vesicle trafficking systems are also identified in vacuolated human oocytes. Furthermore, activating VPS34 with corynoxin B (CB) treatment improved oocyte quality in aged mice. Hence, VPS34 activation may represent a novel approach to enhance oocyte quality in human artificial reproduction.

Autophagy modulation in cancer therapy: Challenges coexist with opportunities

Autophagy, a crucial intracellular degradation process facilitated by lysosomes, plays a pivotal role in maintaining cellular homeostasis. The elucidation of autophagy key genes and signaling pathways has significantly advanced our understanding of this process and has led to the exploration of autophagy as a promising therapeutic approach. This review comprehensively assesses the latest developments in small molecule modulators targeting autophagy. Moreover, the review delves into the most recent strategies for drug discovery, specifically focusing on selective agents that exploit autophagosomes and lysosomes for targeted protein degradation. Additionally, this article highlights the prevailing challenges and outlines potential future advancements in the field. By amalgamating the cutting-edge knowledge in the field, we aim to offer valuable insights and references for the anti-cancer drug development of autophagy-targeted therapies, thus contributing to the advancement of novel therapeutic interventions.

Identification of DNA methylation markers for age and Bovine Respiratory Disease in dairy cattle: A pilot study based on Reduced Representation Bisulfite Sequencing

Methylation profiles of animals are known to differ by age and disease status. Bovine respiratory disease (BRD), a complex infectious disease, primarily affects calves and has significant impact on animal welfare and the cattle industry, due to production losses, increased veterinary costs as well as animal losses. BRD susceptibility is multifactorial, influenced by both environmental and genetic factors. We have performed a pilot study to investigate the epigenetic profile of BRD susceptibility in six calves (three healthy versus three diagnosed with BRD) and age-related methylation differences between healthy calves and adult dairy cows (three calves versus four adult cows) using Reduced Representation Bisulfite Sequencing (RRBS). We identified 2537 genes within differentially methylated regions between calves and adults. Functional analysis revealed enrichment of developmental pathways including cell fate commitment and tissue morphogenesis. Between healthy and BRD affected calves, 964 genes were identified within differentially methylated regions. Immune and vasculature regulatory pathways were enriched and key candidates in BRD susceptibility involved in complement cascade regulation, vasoconstriction and respiratory cilia structure and function were identified. Further studies with a greater sample size are needed to validate these findings and formulate integration into breeding programmes aiming to increase animal longevity and disease resistance.

Treatment-related adverse events in patients with advanced breast cancer receiving adjuvant AKT inhibitors: a meta-analysis of randomized controlled trials

INTRODUCTION

Incorporation of AKT inhibitors into adjuvant therapy for advanced or metastatic breast cancer has improved clinical outcomes. However, the safety of AKT inhibitors should be better evaluated, given the possibility of prolonging survival and impacting patient quality of life. Our aim was to assess how the addition of AKT inhibitors to adjuvant therapy affects treatment-related adverse events.

METHODS

We evaluated binary outcomes with risk ratios (RRs), with 95% confidence intervals (CIs). We used DerSimonian and Laird random-effect models for all endpoints. Heterogeneity was assessed using I2 statistics. R, version 4.2.3, was used for statistical analyses.

RESULTS

A total of seven RCTs comprising 1619 patients with BC. The adverse effects that show significance statistical favoring the occurrence of adverse effects in AKT inhibitor were diarrhea (RR 3.05; 95% CI 2.48-3.75; p < 0.00001; I2 = 49%), hyperglycemia (RR 3.4; 95% CI 1.69-6.83; p = 0.00058; I2 = 75%), nausea (RR 1.69; 95% CI 1.34-2.13; p = 0.000008; I2 = 42%), rash (RR 2.79; 95% CI 1.49-5.23; p = 0.0013; I2 = 82%), stomatitis (RR 2.24; 95% CI 1.69-2.97; p < 0.00001; I2 = 16%) and vomiting (RR 2.99; 95% CI 1.85-4.86; p = 0.00009; I2 = 42%). There was no significant difference between the groups for alopecia (p = 0.80), fatigue (p = 0.087), and neuropathy (p = 0.363380).

CONCLUSION

The addition of AKT inhibitors to adjuvant therapy was associated with an increase in treatment-related adverse events. These results provide safety information for further clinical trials evaluating AKT inhibitor therapy for patients with metastatic BC. Clinicians should closely monitor patients for treatment-related adverse events to avoid discontinuation of therapy and morbidity caused by these early-stage therapies.

Proteogenomic insights into the biology and treatment of pan-melanoma

Melanoma is one of the most prevalent skin cancers, with high metastatic rates and poor prognosis. Understanding its molecular pathogenesis is crucial for improving its diagnosis and treatment. Integrated analysis of multi-omics data from 207 treatment-naïve melanomas (primary-cutaneous-melanomas (CM, n = 28), primary-acral-melanomas (AM, n = 81), primary-mucosal-melanomas (MM, n = 28), metastatic-melanomas (n = 27), and nevi (n = 43)) provides insights into melanoma biology. Multivariate analysis reveals that PRKDC amplification is a prognostic molecule for melanomas. Further proteogenomic analysis combined with functional experiments reveals that the cis-effect of PRKDC amplification may lead to tumor proliferation through the activation of DNA repair and folate metabolism pathways. Proteome-based stratification of primary melanomas defines three prognosis-related subtypes, namely, the ECM subtype, angiogenesis subtype (with a high metastasis rate), and cell proliferation subtype, which provides an essential framework for the utilization of specific targeted therapies for particular melanoma subtypes. The immune classification identifies three immune subtypes. Further analysis combined with an independent anti-PD-1 treatment cohort reveals that upregulation of the MAPK7-NFKB signaling pathway may facilitate T-cell recruitment and increase the sensitivity of patients to immunotherapy. In contrast, PRKDC may reduce the sensitivity of melanoma patients to immunotherapy by promoting DNA repair in melanoma cells. These results emphasize the clinical value of multi-omics data and have the potential to improve the understanding of melanoma treatment.

Differential effects of AKT1 and AKT2 on sleep-wake activity under basal conditions and in response to LPS challenge in mice

Infectious challenge can trigger alterations in sleep-wake behavior. Accumulating evidence has shown that the serine/threonine kinases Akt1 and Akt2 are important targets in both physiological and infectious signaling processes. However, the involvement of Akt1 and Akt2 in sleep-wake activity under basal conditions and in response to inflammatory stimulation has not been established. In the present study, we assessed the precise role of Akt1 and Akt2 in sleep-wake behavior using electroencephalography (EEG)/electromyography (EMG) data from Akt1- and Akt2-deficient mice and wild-type (WT) mice. The results showed that both Akt1 and Akt2 deficiency affect sleep-wake activity, as indicated by reduced nonrapid eye movement (NREM) sleep and increased wakefulness in mutant mice compared to WT mice. Sleep amount and intensity (delta, theta and alpha activity) at night were also drastically attenuated in Akt1- and Akt2-deficient mice. Moreover, since Akt1 and Akt2 are involved in immune responses, we assessed their roles in the sleep response to the inflammatory stimulus lipopolysaccharide (LPS) throughout the following 24 h. We observed that the decrease in wakefulness and increase in NREM sleep induced by LPS were restored in Akt1 knockout mice but not in Akt2 knockout mice. Correspondingly, the decrease in the number of positive orexin-A neurons induced by LPS was abrogated in Akt1 knockout mice but not in Akt2 knockout mice. Our results revealed that both Akt1 and Akt2 deficiency affect the sleep response under basal conditions, but only Akt1 deficiency protects against the aberrant changes in sleep behavior induced by peripheral immune challenge.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-024-00519-y.

Reprogramming of 3D genome structure underlying HSPC development in zebrafish

BACKGROUND

Development of hematopoietic stem and progenitor cells (HSPC) is a multi-staged complex process that conserved between zebrafish and mammals. Understanding the mechanism underlying HSPC development is a holy grail of hematopoietic biology, which is helpful for HSPC clinical application. Chromatin conformation plays important roles in transcriptional regulation and cell fate decision; however, its dynamic and role in HSPC development is poorly investigated.

METHODS

We performed chromatin structure and multi-omics dissection across different stages of HSPC developmental trajectory in zebrafish for the first time, including Hi-C, RNA-seq, ATAC-seq, H3K4me3 and H3K27ac ChIP-seq.

RESULTS

The chromatin organization of zebrafish HSPC resemble mammalian cells with similar hierarchical structure. We revealed the multi-scale reorganization of chromatin structure and its influence on transcriptional regulation and transition of cell fate during HSPC development. Nascent HSPC is featured by loose conformation with obscure structure at all layers. Notably, PU.1 was identified as a potential factor mediating formation of promoter-involved loops and regulating gene expression of HSPC.

CONCLUSIONS

Our results provided a global view of chromatin structure dynamics associated with development of zebrafish HSPC and discovered key transcription factors involved in HSPC chromatin interactions, which will provide new insights into the epigenetic regulatory mechanisms underlying vertebrate HSPC fate decision.

Targeting PI3K/AKT/mTOR signaling to overcome drug resistance in cancer

This review comprehensively explores the challenge of drug resistance in cancer by focusing on the pivotal PI3K/AKT/mTOR pathway, elucidating its role in oncogenesis and resistance mechanisms across various cancer types. It meticulously examines the diverse mechanisms underlying resistance, including genetic mutations, feedback loops, and microenvironmental factors, while also discussing the associated resistance patterns. Evaluating current therapeutic strategies targeting this pathway, the article highlights the hurdles encountered in drug development and clinical trials. Innovative approaches to overcome resistance, such as combination therapies and precision medicine, are critically analyzed, alongside discussions on emerging therapies like immunotherapy and molecularly targeted agents. Overall, this comprehensive review not only sheds light on the complexities of resistance in cancer but also provides a roadmap for advancing cancer treatment.

Investigating the effects of Laggera pterodonta on H3N2-Induced inflammatory and immune responses through network pharmacology, molecular docking, and experimental validation in a mice model

For centuries, Laggera pterodonta (LP), a Chinese herbal medicine, has been widely employed for treating respiratory infectious diseases; however, the mechanism underlying LP's effectiveness against the influenza A/Aichi/2/1968 virus (H3N2) remains elusive. This study aims to shed light on the mechanism by which LP combats influenza in H3N2-infected mice. First, we conducted quasi-targeted metabolomics analysis using liquid chromatography-mass spectrometry to identify LP components. Subsequently, network pharmacology, molecular docking, and simulation were conducted to screen candidate targets associated with AKT and NF-κB. In addition, we conducted a series of experiments including qPCR, hematoxylin-eosin staining, flow cytometry, immunohistochemistry, and enzyme-linked immunosorbent assay to provide evidence that LP treatment in H3N2-infected mice can reduce pro-inflammatory cytokine levels (TNF-α, IL-6, IL-1β, and MCP-1) while increasing T cells (CD3+, CD4+, and CD8+) and syndecan-1 and secretory IgA expression. This, in turn, aids in the prevention of excessive inflammation and the fortification of immunity, both of which are compromised by H3N2. Finally, we utilized a Western blot assay to confirm that LP indeed inhibits the AKT/NF-κB signaling cascade. Thus, the efficacy of LP serves as a cornerstone in establishing a theoretical foundation for influenza treatment.

Synergistic Glutathione Depletion and STING Activation to Potentiate Dendritic Cell Maturation and Cancer Vaccine Efficacy

Dendritic cell (DC) maturation and antigen presentation are key factors for successful vaccine-based cancer immunotherapy. This study developed manganese-based layered double hydroxide (Mn-LDH) nanoparticles as a self-adjuvanted vaccine carrier that not only promoted DC maturation through synergistically depleting endogenous glutathione (GSH) and activating STING signaling pathway, but also facilitated the delivery of model antigen ovalbumin (OVA) into lymph nodes and subsequent antigen presentation in DCs. Significant therapeutic-prophylactic efficacy of the OVA-loaded Mn-LDH (OVA/Mn-LDH) nanovaccine was determined by the tumor growth inhibition in the mice bearing B16-OVA tumor. Our results showed that the OVA/Mn-LDH nanoparticles could be a potent delivery system for cancer vaccine development without the need of adjuvant. Therefore, the combination of GSH exhaustion and STING pathway activation might be an advisable approach for promoting DC maturation and antigen presentation, finally improving cancer vaccine efficacy.

Meiotic and developmental competence of growing pig oocytes derived from small antral follicles is enhanced in culture medium containing FGF2, LIF, and IGF1 (FLI medium)

BACKGROUND

Oocytes of large animal species isolated from small ovarian follicles (< 2 mm) are less competent to support early embryonic development after in vitro maturation and fertilization than their counterparts isolated from medium-sized and preovulatory follicles. This study aimed to assess the effect of a new maturation medium containing FGF2, LIF, and IGF1 (FLI medium) on the meiotic and developmental competence of pig cumulus-oocytes complexes (COCs) derived from the small and medium-sized follicles.

METHODS

The growing oocytes were isolated from 1 to 2 (small follicle; SF) and the fully-grown ones from 3 to 6 (large follicle; LF) mm follicles and matured in a control M199 medium with gonadotropins and EGF and the FLI medium enriched by the triplet of growth factors. The matured oocytes were parthenogenetically activated and cultured to the blastocyst stage. Chromatin configuration before and during the culture and MAP kinase activity were assessed in the oocytes. Finally, the expression of cumulus cell genes previously identified as markers of oocyte quality was assessed.

RESULTS

The maturation and blastocyst rates of oocytes gained from LF were significantly higher than that from SF in the control medium. In contrast, similar proportions of oocytes from LF and SF completed meiosis and developed to blastocysts when cultured in FLI. Most of the oocytes freshly isolated from SF possessed germinal vesicles with fine filaments of chromatin (GV0) or chromatin surrounding the nucleolus (GVI; 30%); the oocytes from LF were mainly in GVI (or GVII) exhibiting a few small lumps of chromatin beneath the nuclear membrane. When cultured in the FLI medium for 16 h, an acceleration of the course of maturation in oocytes both from SF and LF compared to the control medium was observed and a remarkable synchrony in the course of chromatin remodeling was noticed in oocytes from SF and LF.

CONCLUSIONS

This work demonstrates that the enrichment of culture medium by FGF2, LIF, and IGF1 can enhance the meiotic and developmental competence of not only fully-grown, but also growing pig oocytes and significantly thus expanding the number of oocytes available for various assisted reproductive technology applications.

Advances in Research on Type 2 Diabetes Mellitus Targets and Therapeutic Agents

Diabetes mellitus is a chronic multifaceted disease with multiple potential complications, the treatment of which can only delay and prolong the terminal stage of the disease, i.e., type 2 diabetes mellitus (T2DM). The World Health Organization predicts that diabetes will be the seventh leading cause of death by 2030. Although many antidiabetic medicines have been successfully developed in recent years, such as GLP-1 receptor agonists and SGLT-2 inhibitors, single-target drugs are gradually failing to meet the therapeutic requirements owing to the individual variability, diversity of pathogenesis, and organismal resistance. Therefore, there remains a need to investigate the pathogenesis of T2DM in more depth, identify multiple therapeutic targets, and provide improved glycemic control solutions. This review presents an overview of the mechanisms of action and the development of the latest therapeutic agents targeting T2DM in recent years. It also discusses emerging target-based therapies and new potential therapeutic targets that have emerged within the last three years. The aim of our review is to provide a theoretical basis for further advancement in targeted therapies for T2DM.

PI3K/AKT/mTOR signaling transduction pathway and targeted therapies in cancer

The PI3K/AKT/mTOR (PAM) signaling pathway is a highly conserved signal transduction network in eukaryotic cells that promotes cell survival, cell growth, and cell cycle progression. Growth factor signalling to transcription factors in the PAM axis is highly regulated by multiple cross-interactions with several other signaling pathways, and dysregulation of signal transduction can predispose to cancer development. The PAM axis is the most frequently activated signaling pathway in human cancer and is often implicated in resistance to anticancer therapies. Dysfunction of components of this pathway such as hyperactivity of PI3K, loss of function of PTEN, and gain-of-function of AKT, are notorious drivers of treatment resistance and disease progression in cancer. In this review we highlight the major dysregulations in the PAM signaling pathway in cancer, and discuss the results of PI3K, AKT and mTOR inhibitors as monotherapy and in co-administation with other antineoplastic agents in clinical trials as a strategy for overcoming treatment resistance. Finally, the major mechanisms of resistance to PAM signaling targeted therapies, including PAM signaling in immunology and immunotherapies are also discussed.

Exploring the potential of treating chronic liver disease targeting the PI3K/Akt pathway and polarization mechanism of macrophages

Chronic liver disease is a significant public health issue that can lead to considerable morbidity and mortality, imposing an enormous burden on healthcare resources. Understanding the mechanisms underlying chronic liver disease pathogenesis and developing effective treatment strategies are urgently needed. In this regard, the activation of liver resident macrophages, namely Kupffer cells, plays a vital role in liver inflammation and fibrosis. Macrophages display remarkable plasticity and can polarize into different phenotypes according to diverse microenvironmental stimuli. The polarization of macrophages into M1 pro-inflammatory or M2 anti-inflammatory phenotypes is regulated by complex signaling pathways such as the PI3K/Akt pathway. This review focuses on investigating the potential of using plant chemicals targeting the PI3K/Akt pathway for treating chronic liver disease while elucidating the polarization mechanism of macrophages under different microenvironments. Studies have demonstrated that inhibiting M1-type macrophage polarization or promoting M2-type polarization can effectively combat chronic liver diseases such as alcoholic liver disease, non-alcoholic fatty liver disease, and liver fibrosis. The PI3K/Akt pathway acts as a pivotal modulator of macrophage survival, migration, proliferation, and their responses to metabolism and inflammatory signals. Activating the PI3K/Akt pathway induces anti-inflammatory cytokine expression, resulting in the promotion of M2-like phenotype to facilitate tissue repair and resolution of inflammation. Conversely, inhibiting PI3K/Akt signaling could enhance the M1-like phenotype, which exacerbates liver damage. Targeting the PI3K/Akt pathway has tremendous potential as a therapeutic strategy for regulating macrophage polarization and activity to treat chronic liver diseases with plant chemicals, providing new avenues for liver disease treatment.

miEAA 2023: updates, new functional microRNA sets and improved enrichment visualizations

MicroRNAs (miRNAs) are small non-coding RNAs that play a critical role in regulating diverse biological processes. Extracting functional insights from a list of miRNAs is challenging, as each miRNA can potentially interact with hundreds of genes. To address this challenge, we developed miEAA, a flexible and comprehensive miRNA enrichment analysis tool based on direct and indirect miRNA annotation. The latest release of miEAA includes a data warehouse of 19 miRNA repositories, covering 10 different organisms and 139 399 functional categories. We have added information on the cellular context of miRNAs, isomiRs, and high-confidence miRNAs to improve the accuracy of the results. We have also improved the representation of aggregated results, including interactive Upset plots to aid users in understanding the interaction among enriched terms or categories. Finally, we demonstrate the functionality of miEAA in the context of ageing and highlight the importance of carefully considering the miRNA input list. MiEAA is free to use and publicly available at https://www.ccb.uni-saarland.de/mieaa/.

Molecular Mechanisms of the Anti-Inflammatory Effects of Epigallocatechin 3-Gallate (EGCG) in LPS-Activated BV-2 Microglia Cells

Chronic neuroinflammation is associated with many neurodegenerative diseases, such as Alzheimer's. Microglia are the brain's primary immune cells, and when activated, they release various proinflammatory cytokines. Several natural compounds with anti-inflammatory and antioxidant properties, such as epigallocatechin 3-gallate (EGCG), may provide a promising strategy for inflammation-related neurodegenerative diseases involving activated microglia cells. The objective of the current study was to examine the molecular targets underlying the anti-inflammatory effects of EGCG in activated microglia cells. BV-2 microglia cells were grown, stimulated, and treated with EGCG. Cytotoxicity and nitric oxide (NO) production were evaluated. Immunoassay, PCR array, and WES™ Technology were utilized to evaluate inflammatory, neuroprotective modulators as well as signaling pathways involved in the mechanistic action of neuroinflammation. Our findings showed that EGCG significantly inhibited proinflammatory mediator NO production in LPS-stimulated BV-2 microglia cells. In addition, ELISA analysis revealed that EGCG significantly decreases the release of proinflammatory cytokine IL-6 while it increases the release of TNF-α. PCR array analysis showed that EGCG downregulated MIF, CCL-2, and CSF2. It also upregulated IL-3, IL-11, and TNFS10. Furthermore, the analysis of inflammatory signaling pathways showed that EGCG significantly downregulated mRNA expression of mTOR, NF-κB2, STAT1, Akt3, CCL5, and SMAD3 while significantly upregulating the expression of mRNA of Ins2, Pld2, A20/TNFAIP3, and GAB1. Additionally, EGCG reduced the relative protein expression of NF-κB2, mTOR, and Akt3. These findings suggest that EGCG may be used for its anti-inflammatory effects to prevent neurodegenerative diseases.

Regulation of the immune system by the insulin receptor in health and disease

The signaling pathways downstream of the insulin receptor (InsR) are some of the most evolutionarily conserved pathways that regulate organism longevity and metabolism. InsR signaling is well characterized in metabolic tissues, such as liver, muscle, and fat, actively orchestrating cellular processes, including growth, survival, and nutrient metabolism. However, cells of the immune system also express the InsR and downstream signaling machinery, and there is increasing appreciation for the involvement of InsR signaling in shaping the immune response. Here, we summarize current understanding of InsR signaling pathways in different immune cell subsets and their impact on cellular metabolism, differentiation, and effector versus regulatory function. We also discuss mechanistic links between altered InsR signaling and immune dysfunction in various disease settings and conditions, with a focus on age related conditions, such as type 2 diabetes, cancer and infection vulnerability.

Sevoflurane reverses cisplatin resistance in neuroblastoma cells through the linc00473/miR-490-5p/AKT1 axis

OBJECTIVES

To determine whether sevoflurane regulates cisplatin resistance in neuroblastoma cells.

METHODS

The SH-SY5Y cell line with cisplatin-resistant phenotype (SH-SY5Y-SR) was generated. Cells were co-treated with sevoflurane and cisplatin to seek the sevoflurane function on cisplatin resistance. Key targets of sevoflurane treatment were determined using sequencing (ribonucleic acid [RNA-seq]). Cells were then transfected with specific vectors. Linc00473 and microRNA-490-5p (miR-490-5p) levels were detected using reverse transcriptase quantitative real-time reverse transcription PCR (RT-qPCR). Linc00473-miR-490-5p binding was confirmed using a luciferase reporter-gene assay. After treatment, cell proliferation, viability, and caspase-3 activity were measured to determine the effects of treatment on tumor cells. Each experimental result is based on three independent experiments.

RESULTS

Co-treatment with sevoflurane and cisplatin markedly improved the sensitivity of SH-SY5Y-SR cells to cisplatin, which inhibited the occurrence of cisplatin resistance. The RNA-sequencing analysis and RT-qPCR showed that sevoflurane inhibited linc00473 expression. Overexpression of linc00473 promoted cell proliferation, inhibited apoptosis, and promoted cisplatin resistance. The linc00473/miR-490-5p/V-akt murine thymoma viral oncogene homolog 1 (AKT1) axis was found to mediate the regulatory effects of sevoflurane on cisplatin resistance.

CONCLUSION

Sevoflurane has great clinical potential against cisplatin-resistant tumors. Further animal experiments and clinical trials are required to achieve this goal.