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Space-related stressors such as microgravity are associated with cellular and molecular alterations of the immune and inflammatory homeostasis that have been linked to the disorders that astronauts suffer from during their missions. Most of the research of the past 30 years has consistently established that innate adaptive immune cells represent a target of microgravity, which leads to their defective or dysfunctional activation, as well as to an altered ability to produce soluble mediators—e.g., cytokines/chemokines and bioactive lipids—that altogether control tissue homeostasis. Bioactive lipids include a vast array of endogenous molecules of immune origin that control the induction, intensity and outcome of the inflammatory events. However, none of the papers published so far focus on a newly characterized class of lipid mediators called specialized pro-resolving mediators (SPMs), which orchestrate the "resolution of inflammation"—i.e., the active control and confinement of the inflammatory torrent mostly driven by eicosanoids. SPMs are emerging as crucial players in those processes that avoid acute inflammation to degenerate into a chronic event. Given that SPMs, along with their metabolism and signaling, are being increasingly linked to many inflammatory disorders, their study seems of the outmost importance in the research of pathological processes involved in space-related diseases, also with the perspective of developing therapeutic countermeasures. Here, we show that microgravity, simulated in the rotary cell culture system (RCCS) developed by NASA, rearranges SPM receptors both at the gene and protein level, in human monocytes but not in lymphocytes. Moreover, RCCS treatment reduces the biosynthesis of a prominent SPM like resolvin (Rv) D1. These findings strongly suggest that not only microgravity can impair the functioning of immune cells at the level of bioactive lipids directly involved in proper inflammation, but it does so in a cell-specific manner, possibly perturbing immune homeostasis with monocytes being primary targets. [ABSTRACT FROM AUTHOR]

In 2020, a total of 106 original research articles, 84 reviews, and 1 other paper were published within the "Cell Nuclei: Function, Transport and Receptors" section. The overexpression of progerin resulted in an induction of endothelial cell dysfunction characterized by increased inflammation, oxidative stress along with persistent DNA damage, an elevated expression of cell cycle arrest proteins, and cellular senescence. 33003364 13 Conti I., Varano G., Simioni C., Laface I., Milani D., Rimondi E., Neri L.M. miRNAs as influencers of cell-cell communication in tumor microenvironment. [Extracted from the article]

The endosomal sorting complex required for transport (ESCRT) machinery is composed of an articulated architecture of proteins that assemble at multiple cellular sites. The ESCRT machinery is involved in pathways that are pivotal for the physiology of the cell, including vesicle transport, cell division, and membrane repair. The subunits of the ESCRT I complex are mainly responsible for anchoring the machinery to the action site. The ESCRT II subunits function to bridge and recruit the ESCRT III subunits. The latter are responsible for finalizing operations that, independently of the action site, involve the repair and fusion of membrane edges. In this review, we report on the data related to the activity of the ESCRT machinery at two sites: the nuclear membrane and the midbody and the bridge linking cells in the final stages of cytokinesis. In these contexts, the machinery plays a significant role for the protection of genome integrity by contributing to the control of the abscission checkpoint and to nuclear envelope reorganization and correlated resilience. Consistently, several studies show how the dysfunction of the ESCRT machinery causes genome damage and is a codriver of pathologies, such as laminopathies and cancer. [ABSTRACT FROM AUTHOR]

IBD is an uncontrolled inflammatory condition of the gastrointestinal tract, which mainly manifests in two forms: ulcerative colitis (UC) and Crohn's disease (CD). The pathogenesis of IBD appears to be associated with an abnormal response of innate and adaptive immune cells. Innate immunity cells, such as macrophages, mast cells, and granulocytes, can produce proinflammatory (e.g., TNF-α) and oxidative stress (ROS) mediators promoting intestinal damage, and their abnormal responses can induce an imbalance in adaptive immunity, leading to the production of inflammatory cytokines that increase innate immune damage, abate intestinal barrier functions, and aggravate inflammation. Considering that Ca2+ signalling plays a key role in a plethora of cellular functions, this review has the purpose of deepening the potential Ca2+ involvement in IBD pathogenesis. [ABSTRACT FROM AUTHOR]

While the transcription factor GATA-3 is well-established for its crucial role in T cell development, its specific influence on invariant natural killer T (iNKT) cells remains relatively unexplored. Using flow cytometry and single-cell transcriptomic analysis, we demonstrated that GATA-3 deficiency in mice leads to the absence of iNKT2 and iNKT17 cell subsets, as well as an altered distribution of iNKT1 cells. Thymic iNKT cells lacking GATA-3 exhibited diminished expression of PLZF and T-bet, key transcription factors involved in iNKT cell differentiation, and reduced production of Th2, Th17, and cytotoxic effector molecules. Single-cell transcriptomics revealed a comprehensive absence of iNKT17 cells, a substantial reduction in iNKT2 cells, and an increase in iNKT1 cells in GATA-3-deficient thymi. Differential expression analysis highlighted the regulatory role of GATA-3 in T cell activation signaling and altered expression of genes critical for iNKT cell differentiation, such as Icos, Cd127, Eomes, and Zbtb16. Notably, restoration of Icos, but not Cd127, expression could rescue iNKT cell development in GATA-3-deficient mice. In conclusion, our study demonstrates the pivotal role of GATA-3 in orchestrating iNKT cell effector lineage differentiation through the regulation of T cell activation pathways and Icos expression, providing insights into the molecular mechanisms governing iNKT cell development and function. [ABSTRACT FROM AUTHOR]

Autophagy is a highly conserved cellular recycling process which enables eukaryotes to maintain both cellular and overall homeostasis through the catabolic breakdown of intracellular components or the selective degradation of damaged organelles. In recent years, the importance of autophagy in vascular endothelial cells (ECs) has been increasingly recognized, and numerous studies have linked the dysregulation of autophagy to the development of endothelial dysfunction and vascular disease. Here, we provide an overview of the molecular mechanisms underlying autophagy in ECs and our current understanding of the roles of autophagy in vascular biology and review the implications of dysregulated autophagy for vascular disease. Finally, we summarize the current state of the research on compounds to modulate autophagy in ECs and identify challenges for their translation into clinical use. [ABSTRACT FROM AUTHOR]

Mitochondria provide energy for all cellular processes, including reactions associated with cell cycle progression, DNA damage repair, and cilia formation. Moreover, mitochondria participate in cell fate decisions between death and survival. Nek family members have already been implicated in DNA damage response, cilia formation, cell death, and cell cycle control. Here, we discuss the role of several Nek family members, namely Nek1, Nek4, Nek5, Nek6, and Nek10, which are not exclusively dedicated to cell cycle-related functions, in controlling mitochondrial functions. Specifically, we review the function of these Neks in mitochondrial respiration and dynamics, mtDNA maintenance, stress response, and cell death. Finally, we discuss the interplay of other cell cycle kinases in mitochondrial function and vice versa. Nek1, Nek5, and Nek6 are connected to the stress response, including ROS control, mtDNA repair, autophagy, and apoptosis. Nek4, in turn, seems to be related to mitochondrial dynamics, while Nek10 is involved with mitochondrial metabolism. Here, we propose that the participation of Neks in mitochondrial roles is a new functional axis for the Nek family. [ABSTRACT FROM AUTHOR]

Extracellular biophysical properties have particular implications for a wide spectrum of cellular behaviors and functions, including growth, motility, differentiation, apoptosis, gene expression, cell–matrix and cell–cell adhesion, and signal transduction including mechanotransduction. Cells not only react to unambiguously mechanical cues from the extracellular matrix (ECM), but can occasionally manipulate the mechanical features of the matrix in parallel with biological characteristics, thus interfering with downstream matrix-based cues in both physiological and pathological processes. Bidirectional interactions between cells and (bio)materials in vitro can alter cell phenotype and mechanotransduction, as well as ECM structure, intentionally or unintentionally. Interactions between cell and matrix mechanics in vivo are of particular importance in a variety of diseases, including primarily cancer. Stiffness values between normal and cancerous tissue can range between 500 Pa (soft) and 48 kPa (stiff), respectively. Even the shear flow can increase from 0.1–1 dyn/cm2 (normal tissue) to 1–10 dyn/cm2 (cancerous tissue). There are currently many new areas of activity in tumor research on various biological length scales, which are highlighted in this review. Moreover, the complexity of interactions between ECM and cancer cells is reduced to common features of different tumors and the characteristics are highlighted to identify the main pathways of interaction. This all contributes to the standardization of mechanotransduction models and approaches, which, ultimately, increases the understanding of the complex interaction. Finally, both the in vitro and in vivo effects of this mechanics–biology pairing have key insights and implications for clinical practice in tumor treatment and, consequently, clinical translation. [ABSTRACT FROM AUTHOR]

Retinoic acid signaling is indispensable for the completion of spermatogenesis. It is known that loss of retinoic acid nuclear receptor alpha (RARA) induces male sterility due to seminiferous epithelium degeneration. Initial genetic studies established that RARA acts in Sertoli cells, but a recent paper proposed that RARA is also instrumental in germ cells. In the present study, we have re-assessed the function of RARA in germ cells by genetically ablating the Rara gene in spermatogonia and their progenies using a cell-specific conditional mutagenesis approach. We show that loss of Rara in postnatal male germ cells does not alter the histology of the seminiferous epithelium. Furthermore, RARA-deficient germ cells differentiate normally and give rise to normal, living pups. This establishes that RARA plays no crucial role in germ cells. We also tested whether RARA is required in Sertoli cells during the fetal period or after birth. For this purpose, we deleted the Rara gene in Sertoli cells at postnatal day 15 (PN15), i.e., after the onset of the first spermatogenic wave. To do so, we used temporally controlled cell-specific mutagenesis. By comparing the testis phenotypes generated when Rara is lost either at PN15 or at embryonic day 13, we show that RARA exerts all of its functions in Sertoli cells not at the fetal stage but from puberty. [ABSTRACT FROM AUTHOR]

In this paper, we present the role of autologous and allogeneic monocytes from healthy individuals and those of the cancer patients, with a number of distinct cancers, in activating the function of natural killer (NK) cells, in particular, in induction of IFN-γ secretion by the NK cells and the functional capability of secreted IFN-γ in driving differentiation of the tumor cells. In addition, we compared the roles of CD16 signaling as well as sonicated probiotic bacteria AJ2 (sAJ2)-mediated induction and function of IFN-γ-mediated differentiation in tumor cells. We found that monocytes from cancer patients had lower capability to induce functional IFN-γ secretion by the autologous CD16 mAb-treated NK cells in comparison to those from healthy individuals. In addition, when patient monocytes were cultured with NK cells from healthy individuals, they had lower capability to induce functional IFN-γ secretion by the NK cells when compared to those from autologous monocyte/NK cultures from healthy individuals. Activation by sAJ2 or addition of monocytes from healthy individuals to patient NK cells increased the secretion of functional IFN-γ by the NK cells and elevated its functional capability to differentiate tumors. Monocytes from cancer patients were found to express lower CD16 receptors, providing a potential mechanism for their lack of ability to trigger secretion of functional IFN-γ. In addition to in vitro studies, we also conducted in vivo studies in which cancer patients were given oral supplementation of AJ2 and the function of NK cells were studied. Oral ingestion of AJ2 improved the secretion of IFN-γ by patient derived NK cells and resulted in the better functioning of NK cells in cancer patients. Thus, our studies indicate that for successful NK cell immunotherapy, not only the defect in NK cells but also those in monocytes should be corrected. In this regard, AJ2 probiotic bacteria may serve to provide a potential adjunct treatment strategy. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) was recognized as a gaseous signaling molecule, similar to nitric oxide (-NO) and carbon monoxide (CO). The aim of this review is to provide an overview of the formation of hydrogen sulfide (H2S) in the human body. H2S is synthesized by enzymatic processes involving cysteine and several enzymes, including cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE), cysteine aminotransferase (CAT), 3-mercaptopyruvate sulfurtransferase (3MST) and D-amino acid oxidase (DAO). The physiological and pathological effects of hydrogen sulfide (H2S) on various systems in the human body have led to extensive research efforts to develop appropriate methods to deliver H2S under conditions that mimic physiological settings and respond to various stimuli. These functions span a wide spectrum, ranging from effects on the endocrine system and cellular lifespan to protection of liver and kidney function. The exact physiological and hazardous thresholds of hydrogen sulfide (H2S) in the human body are currently not well understood and need to be researched in depth. This article provides an overview of the physiological significance of H2S in the human body. It highlights the various sources of H2S production in different situations and examines existing techniques for detecting this gas. [ABSTRACT FROM AUTHOR]

Familial Exudative Vitreoretinopathy (FEVR), Norrie disease, and persistent fetal vascular syndrome (PFVS) are extremely rare retinopathies that are clinically distinct but are unified by abnormal retinal endothelial cell function, and subsequent irregular retinal vascular development and/or aberrant inner blood-retinal-barrier (iBRB) function. The early angiogenesis of the retina and its iBRB is a delicate process that is mediated by the canonical Norrin Wnt-signaling pathway in retinal endothelial cells. Pathogenic variants in genes that play key roles within this pathway, such as NDP, FZD4, TSPAN12, and LRP5, have been associated with the incidence of these retinal diseases. Recent efforts to further elucidate the etiology of these conditions have not only highlighted their multigenic nature but have also resulted in the discovery of pathological variants in additional genes such as CTNNB1, KIF11, and ZNF408, some of which operate outside of the Norrin Wnt-signaling pathway. Recent discoveries of FEVR-linked variants in two other Catenin genes (CTNND1, CTNNA1) and the Endoplasmic Reticulum Membrane Complex Subunit-1 gene (EMC1) suggest that we will continue to find additional genes that impact the neural retinal vasculature, especially in multi-syndromic conditions. The goal of this review is to briefly highlight the current understanding of the roles of their encoded proteins in retinal endothelial cells to understand the essential functional mechanisms that can be altered to cause these very rare pediatric retinal vascular diseases. [ABSTRACT FROM AUTHOR]

Pyruvate kinase M (PKM) 2 was described to interact with the inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) and suppress its activity. To further investigate the physiological importance of the PKM2:IP3R interaction, we developed and characterized HeLa PKM2 knockout (KO) cells. In the HeLa PKM2 KO cells, the release of Ca2+ to the cytosol appears to be more sensitive to low agonist concentrations than in HeLa wild-type (WT) cells. However, upon an identical IP3-induced Ca2+ release, Ca2+ uptake in the mitochondria is decreased in HeLa PKM2 KO cells, which may be explained by the smaller number of contact sites between the ER and the mitochondria. Furthermore, in HeLa PKM2 KO cells, mitochondria are more numerous, though they are smaller and less branched and have a hyperpolarized membrane potential. TAT-D5SD, a cell-permeable peptide representing a sequence derived from IP3R1 that can disrupt the PKM2:IP3R interaction, induces Ca2+ release into the cytosol and Ca2+ uptake into mitochondria in both HeLa WT and PKM2 KO cells. Moreover, TAT-D5SD induced apoptosis in HeLa WT and PKM2 KO cells but not in HeLa cells completely devoid of IP3Rs. These results indicate that PKM2 separately regulates cytosolic and mitochondrial Ca2+ handling and that the cytotoxic effect of TAT-D5SD depends on IP3R activity but not on PKM2. However, the tyrosine kinase Lck, which also interacts with the D5SD sequence, is expressed neither in HeLa WT nor PKM2 KO cells, and we can also exclude a role for PKM1, which is upregulated in HeLa PKM2 KO cells, indicating that the TAT-D5SD peptide has a more complex mode of action than anticipated. [ABSTRACT FROM AUTHOR]

Tumor metabolism plays a crucial role in sustaining tumorigenesis. There have been increasing reports regarding the role of tumor metabolism in the control of immune cell functions, generating a potent immunosuppressive contexture that can lead to immune escape. The metabolic reprogramming of tumor cells and the immune escape are two major hallmarks of cancer, with several instances of crosstalk between them. In this paper, we review the effects of tumor metabolism on immune cells, focusing on myeloid cells due to their important role in tumorigenesis and immunosuppression from the early stages of the disease. We also discuss ways to target this specific crosstalk in cancer patients. [ABSTRACT FROM AUTHOR]

The current study's objective was to elucidate some currently unknown biological indicators to evaluate the biological nature of cancer-associated fibroblasts (CAFs). For this purpose, four different CAFs, CAFS1, CAFS2, SCC17F and MO-1000, were established using surgical specimens from oral squamous cell carcinomas (OSCC) with different clinical malignant stages (CAFS1 and CAFS2, T2N0M0, stage II; SCC17F and MO-1000, T4aN2bM0, stage IVA). Fibroblasts unrelated to cancer (non-CAFs) were also prepared and used as controls. Initially, confirmation that these four fibroblasts were indeed CAFs was obtained by their mRNA expression using positive and negative markers for the CAF or fibroblasts. To elucidate possible unknown biological indicators, these fibroblasts were subjected to a cellular metabolic analysis by a Seahorse bioanalyzer, in conjugation with 3D spheroid cultures of the cells and co-cultures with a pancreas ductal carcinoma cell line, MIA PaCa-2. The mitochondrial and glycolytic functions of human orbital fibroblasts (HOF) were nearly identical to those of Graves'-disease-related HOF (GOF). In contrast, the characteristics of the metabolic functions of these four CAFs were different from those of human conjunctival fibroblasts (HconF), a representative non-CAF. It is particularly noteworthy that CAFS1 and CAFS2 showed markedly reduced ratios for the rate of oxygen consumption to the extracellular acidification rate, suggesting that glycolysis was enhanced compared to mitochondrial respiration. Similarly, the physical aspects, their appearance and stiffness, of their 3D spheroids and fibroblasts that were induced effects based on the cellular metabolic functions of MIA PaCa-2 were also different between CAFs and non-CAFs, and their levels for CAFS1 or SCC17F were similar to those for CAFS2 or MO-1000 cells, respectively. The findings reported herein indicate that cellular metabolic functions and the physical characteristics of these types of 3D spheroids may be valuable and useful indicators for estimating potential biological diversity among various CAFs. [ABSTRACT FROM AUTHOR]

Retinal ganglion cells (RGCs) are the sole output neurons conveying visual stimuli from the retina to the brain, and dysfunction or loss of RGCs is the primary determinant of visual loss in traumatic and degenerative ocular conditions. Currently, there is a lack of RGC-specific Cre mouse lines that serve as invaluable tools for manipulating genes in RGCs and studying the genetic basis of RGC diseases. The RNA-binding protein with multiple splicing (RBPMS) is identified as the specific marker of all RGCs. Here, we report the generation and characterization of a knock-in mouse line in which a P2A-CreERT2 coding sequence is fused in-frame to the C-terminus of endogenous RBPMS, allowing for the co-expression of RBPMS and CreERT2. The inducible Rbpms-CreERT2 mice exhibited a high recombination efficiency in activating the expression of the tdTomato reporter gene in nearly all adult RGCs as well as in differentiated RGCs starting at E13.5. Additionally, both heterozygous and homozygous Rbpms-CreERT2 knock-in mice showed no detectable defect in the retinal structure, visual function, and transcriptome. Together, these results demonstrated that the Rbpms-CreERT2 knock-in mouse can serve as a powerful and highly desired genetic tool for lineage tracing, genetic manipulation, retinal physiology study, and ocular disease modeling in RGCs. [ABSTRACT FROM AUTHOR]

Studies on host microbiota and their interactions with the central nervous system (CNS) have grown considerably in the last decade. Indeed, it has been widely demonstrated that dysregulations of the bidirectional gut–brain crosstalk are involved in the development of several pathological conditions, including chronic pain. In addition, the activation of central and peripheral glial cells is also implicated in the pathogenesis and progression of pain and other neurodegenerative disorders. Recent preclinical findings suggest that the gut microbiota plays a pivotal role in regulating glial maturation, morphology and function, possibly through the action of different microbial metabolites, including the most studied short-chain fatty acids (SCFAs). Moreover, altered microbiota composition has been reported in CNS disorders characterized by glial cell activation. In this review, we discuss recent studies showing the role of the gut microbiota and the effects of its depletion in modulating the morphology and function of glial cells (microglia and astrocytes), and we hypothesize a possible role for glia–microbiota interactions in the development and maintenance of chronic pain. [ABSTRACT FROM AUTHOR]

The expression of High-temperature requirement factor A4 (HtrA4) mRNA is significantly lower in the chorionic villi of patients with recurrent pregnancy loss (RPL) than in the control group. We conducted an investigation into the cellular functions of HtrA4 using the CRISPR/Cas9 system and shRNA-HtrA4 to create knockout BeWo cells and HtrA4 knockdown JEG3 cells. Our results indicated that the knockout BeWo cells exhibited reduced capacity for invasion and fusion, but increased levels of proliferation and migration, with a significantly shortened cell cycle compared to wild-type cells. Wild-type BeWo cells highly expressed cell invasion- and fusion-related factors, while knockout BeWo cells highly expressed migration-, proliferation-, and cell cycle-related factors. The shRNA-HtrA4 JEG3 cells showed a decreased capacity for invasion, but an increased capacity for migration, accompanied by a decrease in the expression of cell invasion-related factors and an increase in migration-related factors. Moreover, our ELISA results revealed that the serum HtrA4 level was lower in patients with RPL than in the controls. These findings suggest that HtrA4 depletion may be associated with placental dysfunction. [ABSTRACT FROM AUTHOR]

LIM kinase 1 (LIMK1) and LIM kinase 2 (LIMK2) are serine/threonine and tyrosine kinases and the only two members of the LIM kinase family. They play a crucial role in the regulation of cytoskeleton dynamics by controlling actin filaments and microtubule turnover, especially through the phosphorylation of cofilin, an actin depolymerising factor. Thus, they are involved in many biological processes, such as cell cycle, cell migration, and neuronal differentiation. Consequently, they are also part of numerous pathological mechanisms, especially in cancer, where their involvement has been reported for a few years and has led to the development of a wide range of inhibitors. LIMK1 and LIMK2 are known to be part of the Rho family GTPase signal transduction pathways, but many more partners have been discovered over the decades, and both LIMKs are suspected to be part of an extended and various range of regulation pathways. In this review, we propose to consider the different molecular mechanisms involving LIM kinases and their associated signalling pathways, and to offer a better understanding of their variety of actions within the physiology and physiopathology of the cell. [ABSTRACT FROM AUTHOR]

G protein-coupled receptors (GPCRs) are transmembrane signal transducers that regulate a plethora of physiological and pathological processes. Considering the metabolic alterations that characterize tumor cells and the main role that inflammatory responses elicited in tumor initiation and progression, it is no wonder that the action of certain metabolite-sensing GPCRs may be of particular relevance in tumor cells [[46]]. In addition to G proteins, GPCRs can recruit G protein-coupled receptor kinases (GRKs) and arrestins, which are known to be implicated in both the desensitization and responsiveness of GPCRs [[5]]. In particular, GRK-mediated GPCR phosphorylation promotes the binding of -arrestins, which play a role not only in uncoupling receptors from G proteins but also act as adaptors for agonist-induced GPCR endocytosis and kinase activation toward the activation of signaling pathways within endosomes [[6]]. [Extracted from the article]

Background: Antithymocyte globulins (ATG) are T cell-depleting antibodies used in solid organ transplantation for induction therapy in sensitized patients with a high risk of graft rejection. Previously described effects besides the depletion of T cells have suggested additional modes of action and identified further cellular targets. Methods: We examined the transcriptional changes arising in immune cells from human blood after ex vivo stimulation with ATG at the single-cell level to uncover additional mechanisms by which ATG regulates T cell activity and effector functions. Findings: Analysis of the paracrine factors present in the plasma of ATG-treated whole blood revealed high levels of chemokines and cytokines, including interferon-γ (IFN-γ). Furthermore, we identified an increase in the surface expression of the programmed death ligand 1 (PDL-1) on monocytes mediated by the released paracrine factors. In addition, we showed that this induction is dependent on the activation of JAK/STAT signaling via the binding of IFN-γ to interferon-γ receptor 1 (IFN-γR1). Lastly, we demonstrated that the modulation of the immune regulatory axis of programmed cell death protein 1 (PD1) on activated CD8+ T cells with PDL-1 found on monocytes mediated by ATG potently inhibits effector functions including the proliferation and granzyme B release of activated T cells. Interpretation: Together, our findings represent a novel mode of action by which ATG exerts its immunosuppressive effects. [ABSTRACT FROM AUTHOR]

Aging is associated with changes in the immune system, increased inflammation and mitochondrial dysfunction. The relationship between these phenomena and the clinical phenotype of frailty is unclear. Here, we evaluated the immune phenotypes, T cell functions and mitochondrial functions of immune cells in frail and robust older subjects. We enrolled 20 frail subjects age- and gender-matched with 20 robust controls, and T cell phenotype, response to immune stimulation, cytokine production and immune cell mitochondrial function were assessed. Our results showed that numbers of CD4+ and CD8+ T cells were decreased in frail subjects, without impairment to their ratios. Memory and naïve T cells were not significantly affected by frailty, whereas the expression of CD28 but not that of ICOS was decreased in T cells from frail subjects. T cells from robust subjects produced more IL-17 after CD28 stimulation. Levels of serum cytokines were similar in frail subjects and controls. Mitochondrial bioenergetics and ATP levels were significantly lower in immune cells from frail subjects. In conclusion, we suggest that changes in T cell profiles are associated with aging rather than with frailty syndrome; however, changes in T cell response to immune stimuli and reduced mitochondrial activity in immune cells may be considered hallmarks of frailty. [ABSTRACT FROM AUTHOR]

Objective: We aimed to construct the ferritin autophagy regulatory network and illustrate its mechanism in ferroptosis, TME immunity and malignant phenotypes of ovarian cancer. Methods: First, we used Western blot assays and immunohistochemistry to detect the pathway expression in ovarian cancer samples (C-MYC, NCOA4). Then, we performed RIP and FISH analysis to verify the targeted binding of these factors after which we constructed ovarian cancer cell models and detected pathway regulator expression (NCOA4). Co-localization and Western blot assays were used to detect ferritin autophagy in different experimental groups. We selected corresponding kits to assess ROS contents in ovarian cancer cells. MMP was measured using flow cytometry and mitochondrial morphology was observed through TEM. Then, we chose Clone, EdU and Transwell to evaluate the proliferation and invasion abilities of ovarian cancer cells. We used Western blot assays to measure the DAMP content in ovarian cancer cell supernatants. Finally, we constructed tumor bearing models to study the effect of the C-MYC pathway on ovarian cancer tumorigenesis and TME immune infiltration in in vivo conditions. Results: Through pathway expression detection, we confirmed that C-MYC was obviously up-regulated and NCOA4 was obviously down-regulated in ovarian cancer samples, while their expression levels were closely related to the malignancy degree of ovarian cancer. RIP, FISH and cell model detection revealed that C-MYC could down-regulate NCOA4 expression through directly targeted binding with its mRNA. Ferritin autophagy and ferroptosis detection showed that C-MYC could inhibit ferroptosis through NCOA4-mediated ferritin autophagy, thus reducing ROS and inhibiting mitophagy in ovarian cancer cells. Cell function tests showed that C-MYC could promote the proliferation and invasion of ovarian cancer cells through the NCOA4 axis. The Western blot assay revealed that C-MYC could reduce HMGB1 release in ovarian cancer cells through the NCOA4 axis. In vivo experiments showed that C-MYC could promote tumorigenesis and immune evasion in ovarian cancer cells through inhibiting HMGB1 release induced by NCOA4-mediated ferroptosis. Conclusion: According to these results, we concluded that C-MYC could down-regulate NCOA4 expression through directly targeted binding, thus inhibiting ferroptosis and promoting malignant phenotype/immune evasion in ovarian cancer cells through inhibiting ferritin autophagy. [ABSTRACT FROM AUTHOR]

This comprehensive review facilitates our understanding of the complex cell-cell interactions in the development and pathophysiology of pulmonary artery hypertension. In general, it is assumed that mild-to-moderate endoplasmic reticulum (ER) stress can induce cell adaptation responses, while chronic or severe ER stress can provoke a pro-apoptotic response contributing to the development of the cardiac disease. They found that the mitochondrial DNA levels in blood samples correlate with the AF stage and are high, especially in male patients with paroxysmal AF. Although episodes of AF are readily detectable through electrocardiographic (ECG) measurements, these methods of verification are not informative in AF-free intervals and do not enable the evaluation of the AF stage. [Extracted from the article]

The histone demethylase JMJD1C is associated with human platelet counts. The JMJD1C knockout in zebrafish and mice leads to the ablation of megakaryocyte–erythroid lineage anemia. However, the specific expression, function, and mechanism of JMJD1C in megakaryopoiesis remain unknown. Here, we used cell line models, cord blood cells, and thrombocytopenia samples, to detect the JMJD1C expression. ShRNA of JMJD1C and a specific peptide agonist of JMJD1C, SAH-JZ3, were used to explore the JMJD1C function in the cell line models. The actin ratio in megakaryopoiesis for the JMJDC modulation was also measured. Mass spectrometry was used to identify the JMJD1C-interacting proteins. We first show the JMJD1C expression difference in the PMA-induced cell line models, the thrombopoietin (TPO)-induced megakaryocyte differentiation of the cord blood cells, and also the thrombocytopenia patients, compared to the normal controls. The ShRNA of JMJD1C and SAH-JZ3 showed different effects, which were consistent with the expression of JMJD1C in the cell line models. The effort to find the underlying mechanism of JMJD1C in megakaryopoiesis, led to the discovery that SAH-JZ3 decreases F-actin in K562 cells and increases F-actin in MEG-01 cells. We further performed mass spectrometry to identify the potential JMJD1C-interacting proteins and found that the important Ran GTPase interacts with JMJD1C. To sum up, JMJD1C probably regulates megakaryopoiesis by influencing the actin network. [ABSTRACT FROM AUTHOR]

Lysosomes are highly dynamic organelles involved in the breakdown and recycling of macromolecules, cell cycle, cell differentiation, and cell death, among many other functions in eukaryotic cells. Recently, lysosomes have been identified as cellular hubs for the modulation of intracellular signaling pathways, such as the Wnt/beta-catenin pathway. Here we analyzed morphological and functional characteristics of lysosomes in muscle and non-muscle cells during chick myogenesis, as well as their modulation by the Wnt/beta-catenin pathway. Our results show that (i) muscle and non-muscle cells show differences in lysosomal size and its distribution, (ii) lysosomes are found in spherical structures in myoblasts and fibroblasts and tubular structures in myotubes, (iii) lysosomes are found close to the plasma membrane in fibroblasts and close to the nucleus in myoblasts and myotubes, (iv) lysosomal distribution and size are dependent on the integrity of microtubules and microfilaments in myogenic cells, (v) alterations in lysosomal function, in the expression of LAMP2, and in Wnt/beta-catenin pathway affect the distribution and size of lysosomes in myogenic cells, (vi) the effects of the knockdown of LAMP2 on myogenesis can be rescued by the activation of the Wnt/beta-catenin pathway, and (vii) the chloroquine Lys05 is a potent inhibitor of both the Wnt/beta-catenin pathway and lysosomal function. Our data highlight the involvement of the Wnt/beta-catenin pathway in the regulation of the positioning, size, and function of lysosomes during chick myogenesis. [ABSTRACT FROM AUTHOR]

Epithelial ovarian cancer (EOC) patients frequently develop peritoneal metastasis, especially in the human omentum. However, the mechanism underlying this propensity remains unknown. A previous study found that human omental adipose-derived mesenchymal stem cells are potentially involved in ovarian cancer growth and metastasis, but the results were inconsistent and even contradictory. In addition, the underlying mechanisms of visceral adipose metastasis remain poorly understood. Here, our goal is to clarify the role and mechanism of human omental adipose-derived mesenchymal stem cells (HO-ADSCs) in EOC cancer growth and metastasis. We first found that human omental tissue conditioned medium (HO-CM) enhances EOC cell function. Subsequent coculture studies indicated that HO-ADSCs increase the growth, migratory and invasive capabilities of ovarian cancer cells. Then, we demonstrated that exosomes secreted by HO-ADSCs (HO-ADSC exosomes) enhanced ovarian cancer cell function, and further mechanistic studies showed that the FOXM1, Cyclin F, KIF20A, and MAPK signaling pathways were involved in this process. In addition, subcutaneous tumorigenesis and peritoneal metastatic xenograft experiments provided evidence that HO-ADSC exosomes promote ovarian cancer growth and metastasis in vivo. Finally, our clinical studies provided evidence that ascites from ovarian cancer patients enhance EOC cell line proliferation, migration, and invasion in vitro. The present study indicated that HO-ADSC exosomes are secreted into ascites and exert a tumor-promoting effect on EOC growth and metastasis, providing a new perspective and method to develop future novel therapeutic strategies for the treatment of ovarian cancer. [ABSTRACT FROM AUTHOR]

N-methyl-D-aspartate receptors (NMDARs) are important postsynaptic receptors that contribute to normal synaptic function and cell survival; however, when overactivated, as in Huntington's disease (HD), NMDARs cause excitotoxicity. HD-affected striatal neurons show altered NMDAR currents and augmented ratio of surface to internal GluN2B-containing NMDARs, with augmented accumulation at extrasynaptic sites. Fyn protein is a member of the Src kinase family (SKF) with an important role in NMDARs phosphorylation and synaptic localization and function; recently, we demonstrated that Fyn is reduced in several HD models. Thus, in this study, we aimed to explore the impact of HD-mediated altered Fyn levels at post-synaptic density (PSD), and their role in distorted NMDARs function and localization, and intracellular neuroprotective pathways in YAC128 mouse primary striatal neurons. We show that reduced synaptic Fyn levels and activity in HD mouse striatal neurons is related to decreased phosphorylation of synaptic GluN2B-composed NMDARs; this occurs concomitantly with augmented extrasynaptic NMDARs activity and currents and reduced cAMP response element-binding protein (CREB) activation, along with induction of cell death pathways. Importantly, expression of a constitutive active form of SKF reestablishes NMDARs localization, phosphorylation, and function at PSD in YAC128 mouse neurons. Enhanced SKF levels and activity also promotes CREB activation and reduces caspase-3 activation in YAC128 mouse striatal neurons. This work supports, for the first time, a relevant role for Fyn protein in PSD modulation, controlling NMDARs synaptic function in HD, and favoring neuroprotective pathways and cell survival. In this respect, Fyn Tyr kinase constitutes an important potential HD therapeutic target directly acting at PSD. [ABSTRACT FROM AUTHOR]

Despite their homogeneous appearance, Purkinje cells are remarkably diverse with respect to their molecular phenotypes, physiological properties, afferent and efferent connectivity, as well as their vulnerability to insults. Heterogeneity in Purkinje cells arises early in development, with molecularly distinct embryonic cell clusters present soon after Purkinje cell specification. Traditional methods have characterized cerebellar development and cell types, including Purkinje cell subtypes, based on knowledge of selected markers. However, recent single-cell RNA sequencing studies provide vastly increased resolution of the whole cerebellar transcriptome. Here we draw together the results of multiple single-cell transcriptomic studies in developing and adult cerebellum in both mouse and human. We describe how this detailed transcriptomic data has increased our understanding of the intricate development and function of Purkinje cells and provides first clues into features specific to human cerebellar development. [ABSTRACT FROM AUTHOR]

Autophagy performs essential cell functions in the liver through an intracellular lysosomal degradation process. Several studies have reported that autophagy deficiency can lead to liver injury, including hepatic fibrosis; however, the mechanisms underlying the relationship between autophagy deficiency and liver pathology are unclear. In this study, we examined the expression levels of fibrosis-associated genes in hepatocyte-specific ATG7-deficient mice. The expression levels of the connective tissue growth factor (CTGF) and phosphorylated ERK (phospho-ERK) proteins were increased significantly in primary hepatocytes isolated from hepatocyte-specific ATG7-deficient mice compared to those isolated from control mice. In addition, the inhibition of autophagy in cultured mammalian hepatic AML12 and LX2 cells increased CTGF and phospho-ERK protein levels without altering CTGF mRNA expression. In addition, the autophagy deficiency-mediated enhancement of CTGF expression was attenuated when ERK was inhibited. Overall, these results suggest that the inhibition of autophagy in hepatocytes increases phospho-ERK expression, which in turn increases the expression of CTGF, a biomarker of fibrosis. [ABSTRACT FROM AUTHOR]

The anti-inflammatory cytokine interleukin-37 (IL-37) plays a key role in inhibiting innate and adaptive immunity. Past results have shown that IL-37 is elevated in human Treg cells compared to other T cell subsets and contributes to enhancing the Treg transcription factor, forkhead box protein P3 (FOXP3). However, it is unknown if ectopic expression of IL-37 in non-Treg CD4+ T cells can lead to the development of Treg phenotype and function. In the present study, we used a PrimeFlow® RNA assay and confirmed elevated IL37 expression in human Treg cells. We then stably transfected the non-Treg CD4+ T cell leukemia cell line, E6 Jurkat cells, with IL37 and found significant induction of the Treg phenotype. These IL-37-expressing Jurkat cells had elevated CTLA-4 and FOXP3 and produced IL-10. In conjunction with the Treg phenotype, IL-37-expressing Jurkat cells suppressed T cell activation/proliferation, comparable to human primary Treg cells. The creation of this stable human Treg-like cell line has the potential to provide further assistance for in vitro studies of human Treg cells, as it is more convenient than the use of primary human Treg cells. Furthermore, it provides insights into Treg cell biology and function. [ABSTRACT FROM AUTHOR]

SETD8 is a histone methyltransferase that plays pivotal roles in several cellular functions, including transcriptional regulation, cell cycle progression, and genome maintenance. SETD8 regulates the recruitment of 53BP1 to sites of DNA damage by controlling histone H4K20 methylation. Moreover, SETD8 levels are tightly regulated in a cell cycle-dependent manner by ubiquitin-dependent proteasomal degradation. Here, we identified ubiquitin-specific peptidase 29, USP29, as a novel regulator of SETD8. Depletion of USP29 leads to decreased SETD8 protein levels, an effect that is independent of the cell cycle. We demonstrate that SETD8 binds to USP29 in vivo, and this interaction is dependent on the catalytic activity of USP29. Wildtype USP29 can deubiquitinate SETD8 in vivo, indicating that USP29 directly regulates SETD8 protein levels. Importantly, USP29 knockdown inhibits the irradiation-induced increase in H4K20 monomethylation, thereby preventing focus formation of 53BP1 in response to DNA damage. Lastly, depletion of USP29 increases the cellular sensitivity to irradiation. These results demonstrate that USP29 is critical for the DNA damage response and cell survival, likely by controlling protein levels of SETD8. [ABSTRACT FROM AUTHOR]

Organ function relies on microvascular networks to maintain homeostatic equilibrium, which varies widely in different organs and during different physiological challenges. The endothelium role in this critical process can only be evaluated in physiologically relevant contexts. Comparing the responses to oxygen flux in primary murine microvascular EC (MVEC) obtained from brain and lung tissue reveals that supra-physiological oxygen tensions can compromise MVEC viability. Brain MVEC lose mitochondrial activity and undergo significant alterations in electron transport chain (ETC) composition when cultured under standard, non-physiological atmospheric oxygen levels. While glycolytic capacity of both lung and brain MVEC are unchanged by environmental oxygen, the ability to trigger a metabolic shift when oxygen levels drop is greatly compromised following exposure to hyperoxia. This is particularly striking in MVEC from the brain. This work demonstrates that the unique metabolism and function of organ-specific MVEC (1) can be reprogrammed by external oxygen, (2) that this reprogramming can compromise MVEC survival and, importantly, (3) that ex vivo modelling of endothelial function is significantly affected by culture conditions. It further demonstrates that physiological, metabolic and functional studies performed in non-physiological environments do not represent cell function in situ, and this has serious implications in the interpretation of cell-based pre-clinical models. [ABSTRACT FROM AUTHOR]

A proportion of COVID-19 reconvalescent patients develop post-COVID-19 syndrome (PCS) including a subgroup fulfilling diagnostic criteria of Myalgic encephalomyelitis/Chronic Fatigue Syndrome (PCS/CFS). Recently, endothelial dysfunction (ED) has been demonstrated in these patients, but the mechanisms remain elusive. Therefore, we investigated the effects of patients' sera on endothelia cells (ECs) in vitro. PCS (n = 17), PCS/CFS (n = 13), and healthy controls (HC, n = 14) were screened for serum anti-endothelial cell autoantibodies (AECAs) and dysregulated cytokines. Serum-treated ECs were analysed for the induction of activation markers and the release of small molecules by flow cytometry. Moreover, the angiogenic potential of sera was measured in a tube formation assay. While only marginal differences between patient groups were observed for serum cytokines, AECA binding to ECs was significantly increased in PCS/CFS patients. Surprisingly, PCS and PCS/CFS sera reduced surface levels of several EC activation markers. PCS sera enhanced the release of molecules associated with vascular remodelling and significantly promoted angiogenesis in vitro compared to the PCS/CFS and HC groups. Additionally, sera from both patient cohorts induced the release of molecules involved in inhibition of nitric oxide-mediated endothelial relaxation. Overall, PCS and PCS/CFS patients′ sera differed in their AECA content and their functional effects on ECs, i.e., secretion profiles and angiogenic potential. We hypothesise a pro-angiogenic effect of PCS sera as a compensatory mechanism to ED which is absent in PCS/CFS patients. [ABSTRACT FROM AUTHOR]

Autophagy is a highly conserved lysosomal degradation pathway active at basal levels in all cells. However, under stress conditions, such as a lack of nutrients or trophic factors, it works as a survival mechanism that allows the generation of metabolic precursors for the proper functioning of the cells until the nutrients are available. Neurons, as post-mitotic cells, depend largely on autophagy to maintain cell homeostasis to get rid of damaged and/or old organelles and misfolded or aggregated proteins. Therefore, the dysfunction of this process contributes to the pathologies of many human diseases. Furthermore, autophagy is highly active during differentiation and development. In this review, we describe the current knowledge of the different pathways, molecular mechanisms, factors that induce it, and the regulation of mammalian autophagy. We also discuss its relevant role in development and disease. Finally, here we summarize several investigations demonstrating that autophagic abnormalities have been considered the underlying reasons for many human diseases, including liver disease, cardiovascular, cerebrovascular diseases, neurodegenerative diseases, neoplastic diseases, cancers, and, more recently, infectious diseases, such as SARS-CoV-2 caused COVID-19 disease. [ABSTRACT FROM AUTHOR]

Cells possess membraneless ribonucleoprotein (RNP) granules, including stress granules, processing bodies, Cajal bodies, or paraspeckles, that play physiological or pathological roles. RNP granules contain RNA and numerous RNA-binding proteins, transiently formed through the liquid–liquid phase separation. The assembly or disassembly of numerous RNP granules is strongly controlled to maintain their homeostasis and perform their cellular functions properly. Normal RNA granules are reversibly assembled, whereas abnormal RNP granules accumulate and associate with various neurodegenerative diseases. This review summarizes current studies on the physiological or pathological roles of post-translational modifications of various cellular RNP granules and discusses the therapeutic methods in curing diseases related to abnormal RNP granules by autophagy. [ABSTRACT FROM AUTHOR]

Myosin heavy chain 9 (MYH9) gene encodes a protein named non-muscle heavy chain IIA (NMHC IIA), interacting with actin and participating in various biological processes. Mutations in MYH9 cause an array of autosomal dominant disorders, known as MYH9-related diseases (MYH9-RD). However, the role of MYH9 in normal hematopoiesis remains largely unexplored. By using Mx1-cre Myh9 conditional knockout mice, we established an inducible system to precisely inactivate Myh9 function in hematopoietic cells in vivo. The results showed that deletion of Myh9 led to severe defects in hematopoiesis, characterized by pancytopenia, drastic decreases of hematopoietic stem/progenitor cells (HSPC), and bone marrow failure, causing early lethality in mice. The defect in hematopoiesis caused by Myh9 ablation is cell autonomous. In addition, Myh9 deletion impairs HSPC repopulation capacity and increases apoptosis. RNA sequencing results revealed significant alterations in the expression of genes related to HSC self-renewal and maintenance, while multiple signal pathways were also involved, including genes for HSC and myeloid cell development, intrinsic apoptosis, targets of mTOR signaling, and maturity of hematopoietic cells. Our present study suggests an essential role for Myh9 in the survival and maintenance of HSPC in normal hematopoiesis. [ABSTRACT FROM AUTHOR]

All human life starts with a calcium (Ca2+) wave. This ion regulates a plethora of cellular functions ranging from fertilisation and birth to development and cell death. A sophisticated system is responsible for maintaining the essential, tight concentration of calcium within cells. Intricate components of this Ca2+ network are store-operated calcium channels in the cells' membrane. The best-characterised store-operated channel is the Ca2+ release-activated Ca2+ (CRAC) channel. Currents through CRAC channels are critically dependent on the correct function of two proteins: STIM1 and Orai1. A disruption of the precise mechanism of Ca2+ entry through CRAC channels can lead to defects and in turn to severe impacts on our health. Mutations in either STIM1 or Orai1 proteins can have consequences on our immune cells, the cardiac and nervous system, the hormonal balance, muscle function, and many more. There is solid evidence that altered Ca2+ signalling through CRAC channels is involved in the hallmarks of cancer development: uncontrolled cell growth, resistance to cell death, migration, invasion, and metastasis. In this work we highlight the importance of Ca2+ and its role in human health and disease with focus on CRAC channels. [ABSTRACT FROM AUTHOR]

Recently, we have shown that the physiological roles of a multifunctional protein fructose 1,6-bisphosphatase 2 (FBP2, also called muscle FBP) depend on the oligomeric state of the protein. Here, we present several lines of evidence that in HL-1 cardiomyocytes, a forced, chemically induced reduction in the FBP2 dimer-tetramer ratio that imitates AMP and NAD+ action and restricts FBP2-mitochondria interaction, results in an increase in Tau phosphorylation, augmentation of FBP2-Tau and FBP2-MAP1B interactions, disturbance of tubulin network, marked reduction in the speed of mitochondrial trafficking and increase in mitophagy. These results not only highlight the significance of oligomerization for the regulation of FBP2 physiological role in the cell, but they also demonstrate a novel, important cellular function of this multitasking protein—a function that might be crucial for processes that take place during physiological and pathological cardiac remodeling, and during the onset of diseases which are rooted in the destabilization of MT and/or mitochondrial network dynamics. [ABSTRACT FROM AUTHOR]

Early postnatal events are important for the development of the neonatal immune system. Harboring the pioneering microorganisms forming the microbiota of the neonatal gastrointestinal tract is important for priming the immune system, as well as inducing appropriate tolerance to the relatively innocuous environmental antigens and compounds of normal healthy microbiota. Early postnatal supplementation of suitable, safe probiotics could accelerate this process. In the current study, the immunomodulatory capacity of the probiotic strain of Escherichia coli O83:K24:H31 (EcO83) was characterized in vitro and in vivo. We compared the capacity of EcO83 with and without hemolytic activity on selected immune characteristics in vitro as determined by flow cytometry and quantitative real-time PCR. Both strains with and without hemolytic activity exerted comparable capacity on the maturation of dendritic cells while preserving the induction of interleukin 10 (Il10) expression in dendritic cells and T cells cocultured with EcO83 primed dendritic cells. Early postnatal supplementation with EcO83 led to massive but transient colonization of the neonatal gastrointestinal tract, as detected by in vivo bioimaging. Early postnatal EcO83 administration promoted gut barrier function by increasing the expression of claudin and occludin and the expression of Il10. Early postnatal EcO83 application promotes maturation of the neonatal immune system and promotes immunoregulatory and gut barrier functions. [ABSTRACT FROM AUTHOR]

The bergamot polyphenolic fraction (BPF) was evaluated in the F1FO-ATPase activity of swine heart mitochondria. In the presence of a concentration higher than 50 µg/mL BPF, the ATPase activity of F1FO-ATPase, dependent on the natural cofactor Mg2+, increased by 15%, whereas the enzyme activity in the presence of Ca2+ was inhibited by 10%. By considering this opposite BPF effect, the F1FO-ATPase activity involved in providing ATP synthesis in oxidative phosphorylation and triggering mitochondrial permeability transition pore (mPTP) formation has been evaluated. The BPF improved the catalytic coupling of oxidative phosphorylation in the presence of a substrate at the first phosphorylation site, boosting the respiratory control ratios (state 3/state 4) by 25% and 85% with 50 µg/mL and 100 µg/mL BPF, respectively. Conversely, the substrate at the second phosphorylation site led to the improvement of the state 3/state 4 ratios by 15% only with 100 µg/mL BPF. Moreover, the BPF carried out its beneficial effect on the mPTP phenomenon by desensitizing the pore opening. The acute effect of the BPF on the metabolism of porcine aortica endothelial cells (pAECs) showed an ATP rate index greater than one, which points out a prevailing mitochondrial oxidative metabolism with respect to the glycolytic pathway, and this ratio rose by about three times with 100 µg/mL BPF. Consistently, the mitochondrial ATP turnover, in addition to the basal and maximal respiration, were higher in the presence of the BPF than in the controls, and the MTT test revealed an increase in cell viability with a BPF concentration above 200 µg/mL. Therefore, the molecule mixture of the BPF aims to ensure good performance of the mitochondrial bioenergetic parameters. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression and thus act as important regulators of cellular phenotype and function. As their expression may be dysregulated in numerous diseases, they are of interest as biomarkers. What is more, attempts of modulation of some microRNAs for therapeutic reasons have been undertaken. In this review, we discuss the current knowledge regarding the influence of microRNAs on phagocytosis, which may be exerted on different levels, such as through macrophages polarization, phagosome maturation, reactive oxygen species production and cytokines synthesis. This phenomenon plays an important role in numerous pathological conditions. [ABSTRACT FROM AUTHOR]

Hamed and Antonin [[12]] digested how nucleoporins could interact with the nuclear pore membrane and, subsequently, contribute to the assembly and function of nuclear pore complexes that regulate the transport of macromolecules between the nucleus and cytoplasm. The authors eventually developed a simple and efficient protocol to reliably fractionate the nucleus and cytoplasm of both viable and apoptotic cells. For this purpose, adequate subcellular fractionation techniques that distinguish apoptotic bodies and cell fragments from their contaminants are of importance. Senichkin et al. [[2]] compared multiple nucleus/cytoplasm fractionation methods, including those using a Potter-Elvehjem homogenizer, non-ionic detergents (i.e., digitonin and NP-40) and the stepwise lysis of cells and washing of the resultant nuclei with NP-40 at both steps. [Extracted from the article]

Ischemic brain injury represents a major cause of death worldwide with limited treatment options with a narrow therapeutic window. Accordingly, novel treatments that extend the treatment from the early neuroprotective stage to the late regenerative phase may accommodate a much larger number of stroke patients. To this end, stem cell-based regenerative therapies may address this unmet clinical need. Several stem cell therapies have been tested as potentially exhibiting the capacity to regenerate the stroke brain. Based on the long track record and safety profile of transplantable stem cells for hematologic diseases, bone marrow-derived mesenchymal stromal cells or mesenchymal stromal cells have been widely tested in stroke animal models and have reached clinical trials. However, despite the translational promise of MSCs, probing cell function remains to be fully elucidated. Recognizing the multi-pronged cell death and survival processes that accompany stroke, here we review the literature on MSC definition, characterization, and mechanism of action in an effort to gain a better understanding towards optimizing its applications and functional outcomes in stroke. [ABSTRACT FROM AUTHOR]

The RAS/RAF/MEK/ERK (MAPK) signaling cascade is essential for cell inter- and intra-cellular communication, which regulates fundamental cell functions such as growth, survival, and differentiation. The MAPK pathway also integrates signals from complex intracellular networks in performing cellular functions. Despite the initial discovery of the core elements of the MAPK pathways nearly four decades ago, additional findings continue to make a thorough understanding of the molecular mechanisms involved in the regulation of this pathway challenging. Considerable effort has been focused on the regulation of RAF, especially after the discovery of drug resistance and paradoxical activation upon inhibitor binding to the kinase. RAF activity is regulated by phosphorylation and conformation-dependent regulation, including auto-inhibition and dimerization. In this review, we summarize the recent major findings in the study of the RAS/RAF/MEK/ERK signaling cascade, particularly with respect to the impact on clinical cancer therapy. [ABSTRACT FROM AUTHOR]

O-linked β-N-acetylglucosamine (O-GlcNAc) modification regulates the activity of hundreds of nucleocytoplasmic proteins involved in a wide variety of cellular processes, such as gene expression, signaling, and cell growth; however, the mechanism underlying the regulation of B cell development and function by O-GlcNAcylation remains largely unknown. Here, we demonstrate that changes in cellular O-GlcNAc levels significantly affected the growth of pre-B cells, which rapidly proliferate to allow expansion of functional clones that express successfully rearranged heavy chains at the pro-B stage during early B cell development. In our study, the overall O-GlcNAc levels in these proliferative pre-B cells, which are linked to the glucose uptake rate, were highly induced when compared with those in pro-B cells. Thus, pharmacologically, genetically, or nutritionally, inhibition of O-GlcNAcylation in pre-B cells markedly downregulated c-Myc expression, resulting in cell cycle arrest via blockade of cyclin expression. Importantly, the population of B cells after the pro-B cell stage in mouse bone marrow was severely impaired by the administration of an O-GlcNAc inhibitor. These results strongly suggest that O-GlcNAcylation-dependent expression of c-Myc represents a new regulatory component of pre-B cell proliferation, as well as a potential therapeutic target for the treatment of pre-B cell-derived leukemia. [ABSTRACT FROM AUTHOR]

Any given cell type has an associated "normal" nuclear morphology, which is important to maintain proper cellular functioning and safeguard genomic integrity. Deviations from this can be indicative of diseases such as cancer or premature aging syndrome. To accurately assess nuclear abnormalities, it is important to use quantitative measures of nuclear morphology. Here, we give an overview of several nuclear abnormalities, including micronuclei, nuclear envelope invaginations, blebs and ruptures, and review the current methods used for image-based quantification of these abnormalities. We discuss several parameters that can be used to quantify nuclear shape and compare their outputs using example images. In addition, we present new pipelines for quantitative analysis of nuclear blebs and invaginations. Quantitative analyses of nuclear aberrations and shape will be important in a wide range of applications, from assessments of cancer cell anomalies to studies of nucleus deformability under mechanical or other types of stress. [ABSTRACT FROM AUTHOR]

MCPH1, or BRIT1, is often mutated in human primary microcephaly type 1, a neurodevelopmental disorder characterized by a smaller brain size at birth, due to its dysfunction in regulating the proliferation and self-renewal of neuroprogenitor cells. In the last 20 years or so, genetic and cellular studies have identified MCPH1 as a multifaceted protein in various cellular functions, including DNA damage signaling and repair, the regulation of chromosome condensation, cell-cycle progression, centrosome activity and the metabolism. Yet, genetic and animal model studies have revealed an unpredicted essential function of MPCH1 in gonad development and tumorigenesis, although the underlying mechanism remains elusive. These studies have begun to shed light on the role of MPCH1 in controlling various pathobiological processes of the disorder. Here, we summarize the biological functions of MCPH1, and lessons learnt from cellular and mouse models of MCPH1. [ABSTRACT FROM AUTHOR]

Pulse power technology using nanosecond pulsed electric fields (nsPEFs) offers a new stimulus to modulate cell functions or induce cell death for cancer cell ablation. New data and a literature review demonstrate fundamental and basic cellular mechanisms when nsPEFs interact with cellular targets. NsPEFs supra- electroporate cells creating large numbers of nanopores in all cell membranes. While nsPEFs have multiple cellular targets, these studies show that nsPEF-induced dissipation of ΔΨm closely parallels deterioration in cell viability. Increases in intracellular Ca2+ alone were not sufficient for cell death; however, cell death depended of the presence of Ca2+. When both events occur, cell death ensues. Further, direct evidence supports the hypothesis that pulse rise-fall times or high frequency components of nsPEFs are important for decreasing ΔΨm and cell viability. Evidence indicates in Jurkat cells that cytochrome c release from mitochondria is caspase-independent indicating an absence of extrinsic apoptosis and that cell death can be caspase- dependent and --independent. The Ca2+ dependence of nsPEF-induced dissipation of ΔΨm suggests that nanoporation of inner mitochondria membranes is less likely and effects on a Ca2+-dependent protein(s) or the membrane in which it is embedded are more likely a target for nsPEF- induced cell death. The mitochondria permeability transition pore (mPTP) complex is a likely candidate. Data demonstrate that nsPEFs can bypass cancer mutations that evade apoptosis through mechanisms at either the DISC or the apoptosome. [ABSTRACT FROM AUTHOR]

Heat shock proteins (HSPs) are a family of molecular chaperones that regulate essential protein refolding and triage decisions to maintain protein homeostasis. Numerous co-chaperone proteins directly interact and modify the function of HSPs, and these interactions impact the outcome of protein triage, impacting everything from structural proteins to cell signaling mediators. The chaperone/co-chaperone machinery protects against various stressors to ensure cellular function in the face of stress. However, coding mutations, expression changes, and post-translational modifications of the chaperone/co-chaperone machinery can alter the cellular stress response. Importantly, these dysfunctions appear to contribute to numerous human diseases. Therapeutic targeting of chaperones is an attractive but challenging approach due to the vast functions of HSPs, likely contributing to the off-target effects of these therapies. Current efforts focus on targeting co-chaperones to develop precise treatments for numerous diseases caused by defects in protein quality control. This review focuses on the recent developments regarding selected HSP70/HSP90 co-chaperones, with a concentration on cardioprotection, neuroprotection, cancer, and autoimmune diseases. We also discuss therapeutic approaches that highlight both the utility and challenges of targeting co-chaperones. [ABSTRACT FROM AUTHOR]