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Focal Adhesion Kinase (FAK) is a non-receptor tyrosine kinase pivotal in cellular signal transduction, regulating cell adhesion, migration, growth, and survival. However, the regulatory mechanisms of FAK during tumorigenesis and progression still need to be fully understood. Our previous study demonstrated that O-GlcNAcylation regulates integrin-mediated cell adhesion. To further elucidate the underlying molecular mechanism, we focused on FAK in this study and purified it from 293T cells. Using liquid chromatography–mass spectrometry (LC-MS/MS), we identified the O-GlcNAcylation of FAK at Ser708, Thr739, and Ser886. Compared with wild-type FAK expressed in FAK-knockout 293T cells, the FAK mutant, in which Ser708, Thr739, and Ser886 were replaced with Ala, exhibited lower phosphorylation levels of Tyr397 and AKT. Cell proliferation and migration, assessed through MTT and wound healing assays, were significantly suppressed in the FAK mutant cells compared to the wild-type FAK cells. Additionally, the interaction among FAK, paxillin, and talin was enhanced, and cell adhesion was increased in the mutant cells. These data indicate that specific O-GlcNAcylation of FAK plays a critical regulatory role in integrin-mediated cell adhesion and migration. This further supports the idea that O-GlcNAcylation is essential for tumorigenesis and progression and that targeting the O-GlcNAcylation of FAK could offer a promising therapeutic strategy for cancer treatment. [ABSTRACT FROM AUTHOR]

Cells have evolved intricate mechanisms for recognizing and responding to changes in oxygen (O2) concentrations. Here, we have reprogrammed cellular hypoxia (low O2) signaling via gas tunnel engineering of prolyl hydroxylase 2 (PHD2), a non‐heme iron dependent O2 sensor. Using computational modeling and protein engineering techniques, we identify a gas tunnel and critical residues therein that limit the flow of O2 to PHD2's catalytic core. We show that systematic modification of these residues can open the constriction topology of PHD2's gas tunnel. Using kinetic stopped‐flow measurements with NO as a surrogate diatomic gas, we demonstrate up to 3.5‐fold enhancement in its association rate to the iron center of tunnel‐engineered mutants. Our most effectively designed mutant displays 9‐fold enhanced catalytic efficiency (kcat/KM=830±40 M−1 s−1) in hydroxylating a peptide mimic of hypoxia inducible transcription factor HIF‐1α, as compared to WT PHD2 (kcat/KM=90±9 M−1 s−1). Furthermore, transfection of plasmids that express designed PHD2 mutants in HEK‐293T mammalian cells reveal significant reduction of HIF‐1α and downstream hypoxia response transcripts under hypoxic conditions of 1 % O2. Overall, these studies highlight activation of PHD2 as a new pathway to reprogram hypoxia responses and HIF signaling in cells. [ABSTRACT FROM AUTHOR]

Retinal vascular diseases encompass several retinal disorders, including diabetic retinopathy, retinopathy of prematurity, age-related macular degeneration, and retinal vascular occlusion; these disorders are classified as similar groups of disorders due to impaired retinal vascularization. The aim of this review is to address the main signaling pathways involved in the pathogenesis of retinal vascular diseases and to identify crucial molecules and the importance of their interactions. Vascular endothelial growth factor (VEGF) is recognized as a crucial and central molecule in abnormal neovascularization and a key phenomenon in retinal vascular occlusion; thus, anti-VEGF therapy is now the most successful form of treatment for these disorders. Interaction between angiopoietin 2 and the Tie2 receptor results in aberrant Tie2 signaling, resulting in loss of pericytes, neovascularization, and inflammation. Notch signaling and hypoxia-inducible factors in ischemic conditions induce pathological neovascularization and disruption of the blood–retina barrier. An increase in the pro-inflammatory cytokines—TNF-α, IL-1β, and IL-6—and activation of microglia create a persistent inflammatory milieu that promotes breakage of the blood–retinal barrier and neovascularization. Toll-like receptor signaling and nuclear factor-kappa B are important factors in the dysregulation of the immune response in retinal vascular diseases. Increased production of reactive oxygen species and oxidative damage follow inflammation and together create a vicious cycle because each factor amplifies the other. Understanding the complex interplay among various signaling pathways, signaling cascades, and molecules enables the development of new and more successful therapeutic options. [ABSTRACT FROM AUTHOR]

Cutaneous melanoma accounts for the majority of skin cancer-related deaths, and its incidence increases each year. The growing number of melanoma cases, especially in advanced stages, poses a significant socio-medical challenge throughout the world. Extensive research on melanoma pathogenesis identifies UV radiation as the most important factor in melanocytic transformation. Oxidative effects of UV irradiation exert their influence on melanoma pathogenesis primarily through modification of nucleic acids, proteins, and lipids, further disrupting cellular signaling and cell cycle regulation. Its effects extend beyond melanocytes, leading to immunosuppression in the exposed skin tissue, which consequently creates conditions for immune surveillance evasion and further progression. In this review, we focus on the specific molecular changes observed in the UV-dependent oxidative stress environment and their biological consequences in the course of the disease, which have not been considered in previous reviews on melanoma. Nonetheless, data show that the exact role of oxidative stress in melanoma initiation and progression remains unclear, as it affects cancerous cells differently depending on the specific context. A better understanding of the pathophysiological basis of melanoma development holds promise for identifying potential targets, which could lead to effective melanoma prevention strategies. [ABSTRACT FROM AUTHOR]

Mechanical stimuli, such as stretch, shear stress, or compression, activate a range of biomolecular responses through cellular mechanotransduction. In the nervous system, studies on mechanical stress have highlighted key pathophysiological mechanisms underlying traumatic injury and neurodegenerative diseases. However, the biomolecular pathways triggered by mechanical stimuli in the nervous system has not been fully explored, especially compared to other body systems. This gap in knowledge may be due to the wide variety of methods and definitions used in research. Additionally, as mechanical stimulation techniques such as ultrasound and electromagnetic stimulation are increasingly utilized in psychological and neurorehabilitation treatments, it is vital to understand the underlying biological mechanisms in order to develop accurate pathophysiological models and enhance therapeutic interventions. This review aims to summarize the cellular signaling pathways activated by various mechanical and electromagnetic stimuli with a particular focus on the mammalian nervous system. Furthermore, we briefly discuss potential cellular mechanosensors involved in these processes.

Abstract Background Schizophrenia (SCZ) is a severe psychiatric disorder associated with alterations in early brain development. Details of underlying pathomechanisms remain unclear, despite genome and transcriptome studies providing evidence for aberrant cellular phenotypes and pathway deregulation in developing neuronal cells. However, mechanistic insight at the protein level is limited. Methods Here, we investigate SCZ-specific protein expression signatures of neuronal progenitor cells (NPC) derived from patient iPSC in comparison to healthy controls using high-throughput Western Blotting (DigiWest) in a targeted proteomics approach. Results SCZ neural progenitors displayed altered expression and phosphorylation patterns related to Wnt and MAPK signaling, protein synthesis, cell cycle regulation and DNA damage response. Consistent with impaired cell cycle control, SCZ NPCs also showed accumulation in the G2/M cell phase and reduced differentiation capacity. Furthermore, we correlated these findings with elevated p53 expression and phosphorylation levels in SCZ patient-derived cells, indicating a potential implication of p53 in hampering cell cycle progression and efficient neurodevelopment in SCZ. Conclusions Through targeted proteomics we demonstrate that SCZ NPC display coherent mechanistic alterations in regulation of DNA damage response, cell cycle control and p53 expression. These findings highlight the suitability of iPSC-based approaches for modeling psychiatric disorders and contribute to a better understanding of the disease mechanisms underlying SCZ, particularly during early development.

Xiuju Guan,1 Yue Liu,2 Yajuan An,1 Xinshuang Wang,1 Liping Wei,2 Xin Qi2 1School of Graduate Studies, Tianjin University of Traditional Chinese Medicine, Tianjin, People’s Republic of China; 2Department of Cardiology, Tianjin Union Medical Center, Tianjin, People’s Republic of ChinaCorrespondence: Xin Qi, Email qixinx2011@126.comAbstract: Atherosclerosis (AS) is a chronic progressive inflammatory disease of the vascular wall and the primary pathological basis of cardiovascular and cerebrovascular disease. Focal adhesion kinase (FAK) and proline-rich tyrosine kinase 2 (Pyk2), two highly homologous members of the FAK family kinases, play critical roles in integrin signaling. They also serve as scaffolding proteins that contribute to the assembly of cellular signaling complexes that regulate cell survival, cell cycle progression, and cell motility. Research indicates that the FAK family kinases is involved in the gene regulation of vascular cells and that aberrant expression of this family is associated with pathological changes in vascular disease. These findings establish the FAK family kinases as a critical signaling mediator in atherosclerotic lesions and inhibition of its activity has the potential to attenuate the pathological progression of AS. This review highlights the indispensable role of the FAK family kinases in abnormal vascular smooth muscle cell proliferation, endothelial cell dysfunction, inflammation, and lipid metabolism associated with AS. We also summarize therapeutic targets against the FAK family kinases, providing valuable insights into therapeutic strategies for AS.Keywords: FAK family kinases, atherosclerosis, inhibitors, cellular signaling

Mechanical stimuli, such as stretch, shear stress, or compression, activate a range of biomolecular responses through cellular mechanotransduction. In the nervous system, studies on mechanical stress have highlighted key pathophysiological mechanisms underlying traumatic injury and neurodegenerative diseases. However, the biomolecular pathways triggered by mechanical stimuli in the nervous system has not been fully explored, especially compared to other body systems. This gap in knowledge may be due to the wide variety of methods and definitions used in research. Additionally, as mechanical stimulation techniques such as ultrasound and electromagnetic stimulation are increasingly utilized in psychological and neurorehabilitation treatments, it is vital to understand the underlying biological mechanisms in order to develop accurate pathophysiological models and enhance therapeutic interventions. This review aims to summarize the cellular signaling pathways activated by various mechanical and electromagnetic stimuli with a particular focus on the mammalian nervous system. Furthermore, we briefly discuss potential cellular mechanosensors involved in these processes. [ABSTRACT FROM AUTHOR]

Dementia is an umbrella term used to describe deterioration of cognitive function. It is the seventh leading cause of death and is one of the major causes of dependence among older people globally. Alzheimer's Disease (AD) contributes to approximately 60-70% of dementia cases and is characterized by the accumulation of amyloid plaques and tau tangles in the brain. Neuroinflammation is now widely accepted as another disease hallmark, playing a role in both the response to and the perpetuation of disease processes. Microglia are brainresident immune cells that are initially effective at clearing amyloid plaques but contribute to the damaging inflammatory milieu of the brain as disease progresses. Circulating peripheral immune cells contribute to this inflammatory environment through cytokine secretion, creating a positive feedback loop with the microglia. One group of these peripherally derived cytokines acting on microglia is the common cytokine receptor chain family. These cytokines bind heterodimer receptors to activate three major signaling pathways: MAPK, PI3K, and JAK/STAT. This perspective will look at the mechanisms of these three pathways in microglia and highlight the future directions of this research and potential therapeutics. [ABSTRACT FROM AUTHOR]

Chronic rhinosinusitis without nasal polyp (CRSsNP) is characterized by tissue repair/remodeling and the subepithelial stroma region in whose nasal mucosa has been reported by us to have thromboxane A2 (TXA2) prostanoid (TP) receptor and overexpress connective tissue growth factor (CTGF). Therefore, this study aimed to investigate the relationship between TP receptor activation and CTGF production/function in human CRSsNP nasal mucosa stromal fibroblasts. We found that TP agonists including U46619 and IBOP ([1S‐[1α,2α(Z),3β(1E,3 S*),4α]]‐7‐[3‐[3‐hydroxy‐4‐(4‐iodophenoxy)‐1‐butenyl]‐7‐oxabicyclo[2.2.1]hept‐2‐yl]‐5‐heptenoic acid) could promote CTGF protein/messenger RNA expression and secretion. The pharmacological intervention and TP activation assay with U46619 identified the possible participation of PKCμ, PKCδ, nuclear factor‐κB (NF‐κB), and cyclic AMP response element‐binding protein (CREB) phosphorylation/activation in the CTGF induction. Moreover, a phorbol ester—phorbol‐12‐myristate 13‐acetate (PMA) exhibited a similar cellular signaling and CTGF production profile to that elicited by TP activation. However, further small interfering RNA interference analysis revealed that only NF‐κB and PKCδ‐CREB pathways were necessarily required for TP‐mediated CTGF production, which could not be completely supported by those findings from PMA. Finally, in a functional assay, although CTGF did not affect fibroblast proliferation, TP‐mediated CTGF could drive novel self‐migration in fibroblasts both in the scratch/wound healing and transwell apparatus assays. Meanwhile, the overall staining for stress fibers and formation of the lamellipodia and filopodia‐like structures was concomitantly increased in the treated migrating cells. Collectively, we provided here that novel TP mediates CTGF production and self‐migration in human nasal fibroblasts through NF‐κB and PKCδ‐CREB signaling pathways. More importantly, we also demonstrated that thromboxane, TP receptor, CTGF, and stromal fibroblasts may act in concert in the tissue remodeling/repair process during CRSsNP development and progression. [ABSTRACT FROM AUTHOR]

Irisin is a recently discovered myokine that facilitates the browning of white adipose tissue, increases glucose uptake in skeletal muscle, and influences metabolic processes in the liver. However, its potential effects on amino acid absorption remained largely unexplored. This study aimed to elucidate the role of irisin in modulating amino acid uptake and delineate the underlying molecular mechanisms involved. To this end, juvenile tilapia were administered intraperitoneal irisin injections at 100 ng/g body weight over 8 weeks. Evaluation of various physiological parameters revealed that irisin supplementation significantly improved the specific growth rate and feed conversion efficiency while reducing feed consumption. Muscle tissue analysis revealed that irisin significantly modified the proximate composition by increasing protein content and reducing lipid levels. It also significantly raised the levels of both essential and non-essential amino acids in the muscle. Histological analysis demonstrated that irisin-stimulated muscle growth through hyperplasia rather than hypertrophy, corroborated by upregulated IGF-1 mRNA and downregulated myostatin mRNA expression. Mechanistic studies in cultured tilapia muscle cells elucidated that irisin activated integrin receptors on muscle cells, which subsequently engaged IGF-1/IGF-1R signaling. Downstream of IGF-1R activation, irisin simultaneously stimulates the ERK1/2 and PI3K/mTORC2/Akt pathways. The convergence of these pathways upregulates L-type amino acid transporter 1 expression, thereby augmenting amino acid uptake into muscle cells. In summary, irisin supplementation in tilapia leads to improved muscle growth, predominantly via hyperplasia and augmented amino acid assimilation, governed by intricate cellular signaling pathways. These findings provide valuable aquaculture applications and novel insights into muscle development. [ABSTRACT FROM AUTHOR]

Introduction: Exosomes, a subset of extracellular vesicles (EVs), are crucial for intercellular communication in various contexts. Despite their small size, they carry diverse cargo, including RNA, proteins, and lipids. Internalization by recipient cells raises concerns about potential disruptions to cellular functions. Notably, the ability of exosomes to traverse the blood-brain barrier (BBB) has significant implications. Methods: To conduct a thorough investigation into the existing academic literature on exosomes within the framework of neuron-glia communication, a comprehensive search strategy was implemented across the PubMed, Google Scholar, and Science Direct databases. Multiple iterations of the keywords "exosome," "neuron-glia communication," and "neurological disorders" were employed to systematically identify relevant publications. Furthermore, an exploration of the Clinicaltrials. gov database was undertaken to identify clinical trials related to cellular signaling, utilizing analogous terminology. Results: Although the immediate practical applications of exosomes are somewhat limited, their potential as carriers of pathogenic attributes offers promising opportunities for the development of precisely targeted therapeutic strategies for neurological disorders. This review presents a comprehensive overview of contemporary insights into the pivotal roles played by exosomes as agents mediating communication between neurons and glial cells within the central nervous system (CNS). Conclusion: By delving into the intricate dynamics of exosomal communication in the CNS, this review contributes to a deeper understanding of the roles of exosomes in both physiological and pathological processes, thereby paving the way for potential therapeutic advancements in the field of neurological disorders. [ABSTRACT FROM AUTHOR]

Protein kinase B (AKT1) is a serine/threonine kinase that regulates fundamental cellular processes, including cell survival, proliferation, and metabolism. AKT1 activity is controlled by two regulatory phosphorylation sites (Thr308, Ser473) that stimulate a downstream signaling cascade through phosphorylation of many target proteins. At either or both regulatory sites, hyperphosphorylation is associated with poor survival outcomes in many human cancers. Our previous biochemical and chemoproteomic studies showed that the phosphorylated forms of AKT1 have differential selectivity toward peptide substrates. Here, we investigated AKT1‐dependent activity in human cells, using a cell‐penetrating peptide (transactivator of transcription, TAT) to deliver inactive AKT1 or active phospho‐variants to cells. We used enzyme engineering and genetic code expansion relying on a phosphoseryl‐transfer RNA (tRNA) synthetase (SepRS) and tRNASep pair to produce TAT‐tagged AKT1 with programmed phosphorylation at one or both key regulatory sites. We found that all TAT‐tagged AKT1 variants were efficiently delivered into human embryonic kidney (HEK 293T) cells and that only the phosphorylated AKT1 (pAKT1) variants stimulated downstream signaling. All TAT‐pAKT1 variants induced glycogen synthase kinase (GSK)‐3α phosphorylation, as well as phosphorylation of ribosomal protein S6 at Ser240/244, demonstrating stimulation of downstream AKT1 signaling. Fascinatingly, only the AKT1 variants phosphorylated at S473 (TAT‐pAKT1S473 or TAT‐pAKT1T308,S473) were able to increase phospho‐GSK‐3β levels. Although each TAT‐pAKT1 variant significantly stimulated cell proliferation, cells transduced with TAT‐pAKT1T308 grew significantly faster than with the other pAKT1 variants. The data demonstrate differential activity of the AKT1 phospho‐forms in modulating downstream signaling and proliferation in human cells. [ABSTRACT FROM AUTHOR]

The mitogen‐activated protein kinase kinase 4 (MKK4), a member of the MAP kinase kinase family, directly phosphorylates and activates the c‐Jun NH2‐terminal kinases (JNK), in response to proinflammatory cytokines and cellular stresses. Regulation of the MKK4 activity is considered to be a novel approach for the prevention and treatment of inflammation. The aim of this study was to identify whether fisetin, a potential anti‐inflammatory compound, targets MKK4‐JNK cascade to inhibit lipopolysaccharide (LPS)‐stimulated inflammatory response. RAW264 macrophage pretreated with fisetin following LPS stimulation was used as a cell model to investigate the transactivation and expression of related‐inflammatory genes by transient transfection assay, electrophoretic mobility shift assay (EMSA), or enzyme‐linked immunosorbent assay (ELISA), and cellular signaling as well as binding of related‐signal proteins by Western blot, pull‐down assay and kinase assay, and molecular modeling. The transactivation and expression of cyclooxygenase‐2 (COX‐2) gene as well as prostaglandin E2 (PGE2) secretion induced by LPS were inhibited by fisetin in a dose‐dependent manner. Signaling transduction analysis demonstrated that fisetin selectively inhibited MKK4‐JNK1/2 signaling to suppress the phosphorylation of transcription factor AP‐1 without affecting the NF‐κB and Jak2‐Stat3 signaling as well as the phosphorylation of Src, Syk, and TAK1. Furthermore, in vitro and ex vivo pull‐down assay using cell lysate or purified protein demonstrated that fisetin could bind directly to MKK4. Molecular modeling using the Molecular Operating Environment™ software indicated that fisetin docked into the ATP‐binding pocket of MKK4 with a binding energy of −71.75 kcal/mol and formed a 1.70 Å hydrogen bound with Asp247 residue of MKK4. The IC50 of fisetin against MKK4 was estimated as 2.899 μM in the kinase assay, and the ATP‐competitive effect was confirmed by ATP titration. Taken together, our data revealed that fisetin is a potent selective ATP‐competitive MKK4 inhibitor to suppress MKK4‐JNK1/2‐AP‐1 cascade for inhibiting LPS‐induced inflammation. [ABSTRACT FROM AUTHOR]

Allosteric regulation is classically defined as action at a distance, where a perturbation outside of a protein active site affects function. While this definition has motivated many studies of allosteric mechanisms at the level of protein structure, translating these insights to the allosteric regulation of entire cellular processes - and their crosstalk - has received less attention, despite the broad importance of allostery for cellular regulation foreseen by Jacob and Monod. Here, we revisit an evolutionary model for the widespread emergence of allosteric regulation in colocalized proteins, describe supporting evidence, and discuss emerging advances in mapping allostery in cellular networks that link precise and often allosteric perturbations at the molecular level to functional changes at the pathway and systems levels.

FMS-like tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase expressed in hematopoietic cells. Internal-tandem duplication domain (ITD) mutation and tyrosine kinase domain (TKD) mutation are the two most common mutations in acute myeloid leukemia (AML). Post-translational modifications (PTMs) of FLT3, such as glycosylation and ubiquitination, have been shown to impact various aspects of the protein in both wild-type (WT) and mutant forms of FLT3. In this review, we describe how the glycosylation status of FLT3 affects its subcellular localization, which significantly impacts the activation of downstream signaling, and the impact of specific ubiquitination on FLT3 function and stability, which may be associated with disease progression. Moreover, potential novel therapeutic strategies involving a combination of FLT3 tyrosine kinase inhibitors and drugs targeting glycosylation or ubiquitination are discussed.

Background: The epididymis has long been of interest owing to its role in promoting the functional maturation of the male germline. More recent evidence has also implicated the epididymis as an important sensory tissue responsible for remodeling of the sperm epigenome, both under physiological conditions and in response to diverse forms of environmental stress. Despite this knowledge, the intricacies of the molecular pathways involved in regulating the adaptation of epididymal tissue to paternal stressors remains to be fully resolved. Objective: The overall objective of this study was to investigate the direct impact of corticosterone challenge on a tractable epididymal epithelial cell line (i.e., mECap18 cells), in terms of driving adaptation of the cellular proteome and phosphoproteome signaling networks. Materials and methods: The newly developed phosphoproteomic platform EasyPhos coupled with sequencing via an Orbitrap Exploris 480 mass spectrometer, was applied to survey global changes in the mECap18 cell (phospho)proteome resulting from sub‐chronic (10‐day) corticosterone challenge. Results: The imposed corticosterone exposure regimen elicited relatively subtle modifications of the global mECap18 proteome (i.e., only 73 out of 4171 [∼1.8%] proteins displayed altered abundance). By contrast, ∼15% of the mECap18 phosphoproteome was substantially altered following corticosterone challenge. In silico analysis of the corresponding parent proteins revealed an activation of pathways linked to DNA damage repair and oxidative stress responses as well as a reciprocal inhibition of pathways associated with organismal death. Corticosterone challenge also induced the phosphorylation of several proteins linked to the biogenesis of microRNAs. Accordingly, orthogonal validation strategies confirmed an increase in DNA damage, which was ameliorated upon selective kinase inhibition, and an altered abundance profile of a subset of microRNAs in corticosterone‐treated cells. Conclusions: Together, these data confirm that epididymal epithelial cells are reactive to corticosterone challenge, and that their response is tightly coupled to the opposing action of cellular kinases and phosphatases. [ABSTRACT FROM AUTHOR]

Successful pregnancy depends on precise molecular regulation of uterine physiology, especially during the menstrual cycle. Deregulated oxidative stress (OS), often influenced by inflammatory changes but also by environmental factors, represents a constant threat to this delicate balance. Oxidative stress induces a reciprocally regulated nuclear factor erythroid 2-related factor 2/peroxisome proliferator-activated receptor-gamma (Nrf2/PPARγ) pathway. However, increased PPARγ activity appears to be a double-edged sword in endometrial physiology. Activated PPARγ attenuates inflammation and attenuates OS to restore redox homeostasis. However, it also interferes with physiological processes during the menstrual cycle, such as hormonal signaling and angiogenesis. This review provides an elucidation of the molecular mechanisms that support the interplay between PPARγ and OS. Additionally, it offers fresh perspectives on the Nrf2/PPARγ pathway concerning endometrial receptivity and its potential implications for infertility. [ABSTRACT FROM AUTHOR]

The rapid development of the COVID-19 pandemic resulted in a closer analysis of cell functioning during β-coronavirus infection. This review will describe evidence for COVID-19 as a syndrome with a strong, albeit still underestimated, mitochondrial component. Due to the sensitivity of host mitochondria to coronavirus infection, SARS-CoV-2 affects mitochondrial signaling, modulates the immune response, modifies cellular energy metabolism, induces apoptosis and ageing, worsening COVID-19 symptoms which can sometimes be fatal. Various aberrations across human systems and tissues and their relationships with mitochondria were reported. In this review, particular attention is given to characterization of multiple alterations in gene expression pattern and mitochondrial metabolism in COVID-19; the complexity of interactions between SARS-CoV-2 and mitochondrial proteins is presented. The participation of mitogenome fragments in cell signaling and the occurrence of SARS-CoV-2 subgenomic RNA within membranous compartments, including mitochondria is widely discussed. As SARS-CoV-2 severely affects the quality system of mitochondria, the cellular background for aberrations in mitochondrial dynamics in COVID-19 is additionally characterized. Finally, perspectives on the mitigation of COVID-19 symptoms by affecting mitochondrial biogenesis by numerous compounds and therapeutic treatments are briefly outlined. [ABSTRACT FROM AUTHOR]

Omega 3 (ω3) fatty acids have been described since the 1980s as promising anti-inflammatory substances. Prostaglandin and leukotriene modulation were exhaustively explored as the main reason for ω3 beneficial outcomes. However, during the early 2000s, after the human genome decoding advent, the nutrigenomic approaches exhibited an impressive plethora of ω3 targets, now under the molecular point of view. Different G protein-coupled receptors (GPCRs) recognizing ω3 and its derivatives appear to be responsible for blocking inflammation and insulin-sensitizing effects. A new class of ω3-derived substances, such as maresins, resolvins, and protectins, increases ω3 actions. Inflammasome disruption, the presence of GPR120 on immune cell surfaces, and intracellular crosstalk signaling mediated by PPARγ compose the last discoveries regarding the multipoint anti-inflammatory targets for this nutrient. This review shows a detailed mechanistic proposal to understand ω3 fatty acid action over the inflammatory environment in the background of several chronic diseases. [ABSTRACT FROM AUTHOR]

Background: “One for all, and all for one,” the famous rallying cry of the Three Musketeers, in Alexandre Dumas’s popular novel, certainly applies to the 20,000 cells composing the suprachiasmatic nuclei (SCN). These cells work together to form the central clock that coordinates body rhythms in tune with the day-night cycle. Like virtually every body cell, individual SCN cells exhibit autonomous circadian oscillations, but this rhythmicity only reaches a high level of precision and robustness when the cells are coupled with their neighbors. Therefore, understanding the functional network organization of SCN cells beyond their core rhythmicity is an important issue in circadian biology. Summary: The present review summarizes the main results from our recent study demonstrating the feasibility of recording SCN cells in freely moving mice and the significance of variations in intracellular calcium over several timescales. Key Message: We discuss how in vivo imaging at the cell level will be pivotal to interrogate the mammalian master clock, in an integrated context that preserves the SCN network organization, with intact inputs and outputs. [ABSTRACT FROM AUTHOR]

Acetylcholine-activated receptors are divided broadly into two major structurally distinct classes: ligand-gated ion channel nicotinic and G-protein-coupled muscarinic receptors. Each class encompasses several structurally related receptor subtypes with distinct patterns of tissue expression and post-receptor signal transduction mechanisms. The activation of both nicotinic and muscarinic cholinergic receptors has been associated with the induction and progression of gastrointestinal neoplasia. Herein, after briefly reviewing the classification of acetylcholine-activated receptors and the role that nicotinic and muscarinic cholinergic signaling plays in normal digestive function, we consider the mechanics of acetylcholine synthesis and release by neuronal and non-neuronal cells in the gastrointestinal microenvironment, and current methodology and challenges in measuring serum and tissue acetylcholine levels accurately. Then, we critically evaluate the evidence that constitutive and ligand-induced activation of acetylcholine-activated receptors plays a role in promoting gastrointestinal neoplasia. We focus primarily on adenocarcinomas of the stomach, pancreas, and colon, because these cancers are particularly common worldwide and, when diagnosed at an advanced stage, are associated with very high rates of morbidity and mortality. Throughout this comprehensive review, we concentrate on identifying novel ways to leverage these observations for prognostic and therapeutic purposes. [ABSTRACT FROM AUTHOR]

We explored the functional redundancy of three structurally related KCTD (Potassium Channel Tetramerization Domain) proteins, KCTD2, KCTD5, and KCTD17, by progressively knocking them out in HEK 293 cells using CRISPR/Cas9 genome editing. After validating the knockout, we assessed the effects of progressive knockout on cell growth and gene expression. We noted that the progressive effects of knockout of KCTD isoforms on cell growth were most pervasive when all three isoforms were deleted, suggesting some functions were conserved between them. This was also reflected in progressive changes in gene expression. Our previous work indicated that Gβ1 was involved in the transcriptional control of gene expression, so we compared the gene expression patterns between GNB1 and KCTD KO. Knockout of GNB1 led to numerous changes in the expression levels of other G protein subunit genes, while knockout of KCTD isoforms had the opposite effect, presumably because of their role in regulating levels of Gβ1. Our work demonstrates a unique relationship between KCTD proteins and Gβ1 and a global role for this subfamily of KCTD proteins in maintaining the ability of cells to survive and proliferate. [ABSTRACT FROM AUTHOR]

Dementia is an umbrella term used to describe deterioration of cognitive function. It is the seventh leading cause of death and is one of the major causes of dependence among older people globally. Alzheimer’s Disease (AD) contributes to approximately 60–70% of dementia cases and is characterized by the accumulation of amyloid plaques and tau tangles in the brain. Neuroinflammation is now widely accepted as another disease hallmark, playing a role in both the response to and the perpetuation of disease processes. Microglia are brain-resident immune cells that are initially effective at clearing amyloid plaques but contribute to the damaging inflammatory milieu of the brain as disease progresses. Circulating peripheral immune cells contribute to this inflammatory environment through cytokine secretion, creating a positive feedback loop with the microglia. One group of these peripherally derived cytokines acting on microglia is the common cytokine receptor γ chain family. These cytokines bind heterodimer receptors to activate three major signaling pathways: MAPK, PI3K, and JAK/STAT. This perspective will look at the mechanisms of these three pathways in microglia and highlight the future directions of this research and potential therapeutics.

Abstract Colorectal cancer (CRC) is a heterogenous malignancy underpinned by dysregulation of cellular signaling pathways. Previous literature has implicated aberrant JAK/STAT3 signal transduction in the development and progression of solid tumors. In this study we investigate the effectiveness of inhibiting JAK/STAT3 in diverse CRC models, establish in which contexts high pathway expression is prognostic and perform in depth analysis underlying phenotypes. In this study we investigated the use of JAK inhibitors for anti-cancer activity in CRC cell lines, mouse model organoids and patient-derived organoids. Immunohistochemical staining of the TransSCOT clinical trial cohort, and 2 independent large retrospective CRC patient cohorts was performed to assess the prognostic value of JAK/STAT3 expression. We performed mutational profiling, bulk RNASeq and NanoString GeoMx® spatial transcriptomics to unravel the underlying biology of aberrant signaling. Inhibition of signal transduction with JAK1/2 but not JAK2/3 inhibitors reduced cell viability in CRC cell lines, mouse, and patient derived organoids (PDOs). In PDOs, reduced Ki67 expression was observed post-treatment. A highly significant association between high JAK/STAT3 expression within tumor cells and reduced cancer-specific survival in patients with high stromal invasion (TSPhigh) was identified across 3 independent CRC patient cohorts, including the TrasnSCOT clinical trial cohort. Patients with high phosphorylated STAT3 (pSTAT3) within the TSPhigh group had higher influx of CD66b + cells and higher tumoral expression of PDL1. Bulk RNAseq of full section tumors showed enrichment of NFκB signaling and hypoxia in these cases. Spatial deconvolution through GeoMx® demonstrated higher expression of checkpoint and hypoxia-associated genes in the tumor (pan-cytokeratin positive) regions, and reduced lymphocyte receptor signaling in the TME (pan-cytokeratin- and αSMA-) and αSMA (pan-cytokeratin- and αSMA +) areas. Non-classical fibroblast signatures were detected across αSMA + regions in cases with high pSTAT3. Therefore, in this study we have shown that inhibition of JAK/STAT3 represents a promising therapeutic strategy for patients with stromal-rich CRC tumors. High expression of JAK/STAT3 proteins within both tumor and stromal cells predicts poor outcomes in CRC, and aberrant signaling is associated with distinct spatially-dependant differential gene expression.

Focal Adhesion Kinase (FAK) is a non-receptor tyrosine kinase pivotal in cellular signal transduction, regulating cell adhesion, migration, growth, and survival. However, the regulatory mechanisms of FAK during tumorigenesis and progression still need to be fully understood. Our previous study demonstrated that O-GlcNAcylation regulates integrin-mediated cell adhesion. To further elucidate the underlying molecular mechanism, we focused on FAK in this study and purified it from 293T cells. Using liquid chromatography–mass spectrometry (LC-MS/MS), we identified the O-GlcNAcylation of FAK at Ser708, Thr739, and Ser886. Compared with wild-type FAK expressed in FAK-knockout 293T cells, the FAK mutant, in which Ser708, Thr739, and Ser886 were replaced with Ala, exhibited lower phosphorylation levels of Tyr397 and AKT. Cell proliferation and migration, assessed through MTT and wound healing assays, were significantly suppressed in the FAK mutant cells compared to the wild-type FAK cells. Additionally, the interaction among FAK, paxillin, and talin was enhanced, and cell adhesion was increased in the mutant cells. These data indicate that specific O-GlcNAcylation of FAK plays a critical regulatory role in integrin-mediated cell adhesion and migration. This further supports the idea that O-GlcNAcylation is essential for tumorigenesis and progression and that targeting the O-GlcNAcylation of FAK could offer a promising therapeutic strategy for cancer treatment.

Cells convey information about their extracellular environment to their core functional machineries. Studying the capacity of intracellular signaling pathways to transmit information addresses fundamental questions about living systems. Here, we review how information-theoretic approaches have been used to quantify information transmission by signaling pathways that are functionally pleiotropic and subject to molecular stochasticity. We describe how recent advances in machine learning have been leveraged to address the challenges of complex temporal trajectory datasets and how these have contributed to our understanding of how cells employ temporal coding to appropriately adapt to environmental perturbations.

Fms‐like tyrosine kinase‐3 (FLT3) is a commonly mutated gene in acute myeloid leukemia (AML). The two most common mutations are the internal‐tandem duplication domain (ITD) mutation and the tyrosine kinase domain (TKD) mutation. FLT3‐ITD and FLT3‐TKD exhibit distinct protein stability, cellular localization, and intracellular signaling. To understand the underlying mechanisms, we performed proximity labeling with TurboID to identify proteins that regulate FLT3‐ITD or ‐TKD differently. We found that BRCA1/BRCA2‐containing complex subunit 36 (BRCC36), a specific K63‐linked polyubiquitin deubiquitinase, was exclusively associated with ITD, not the wild type of FLT3 and TKD. Knockdown of BRCC36 resulted in decreased signal transducers and activators of transcription 5 phosphorylation and cell proliferation in ITD cells. Consistently, treatment with thiolutin, an inhibitor of BRCC36, specifically suppressed cell proliferation and induced cell apoptosis in ITD cells. Thiolutin efficiently affected leukemia cell lines expressing FLT3‐ITD cell viability and exhibited mutual synergies with quizartinib, a standard clinical medicine for AML. Furthermore, mutation of the lysine at 609 of ITD led to significant suppression of K63 polyubiquitination and decreased its stability, suggesting that K609 is a critical site for K63 ubiquitination specifically recognized by BRCC36. These data indicate that BRCC36 is a specific regulator for FLT3‐ITD, which may shed light on developing a novel therapeutic approach for AML. [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]

Cilia are organelles extend from cells to sense external signals for tuning intracellular signaling for optimal cellular functioning. They have evolved sensory and motor roles in various cells for tissue organization and homeostasis in development and post-development. More than a thousand genes are required for cilia function. Mutations in them cause multisystem disorders termed ciliopathies. The null mutations in CC2D2A result in Meckel syndrome (MKS), which is embryonic lethal, whereas patients who have missense mutations in the C2 domain of CC2D2A display Joubert syndrome (JBTS). They survive with blindness and mental retardation. How C2 domain defects cause disease conditions is not understood. To answer this question, C2 domain of Cc2d2a (mice gene) was knocked down (KD) in IMCD-3 cells by shRNA. This resulted in defective cilia morphology observed by immunofluorescence analysis. To further probe the cellular signaling alteration in affected cells, gene expression profiling was done by RNAseq and compared with the controls. Bioinformatics analysis revealed that the differentially expressed genes (DEGs) have functions in cilia. Among the 61 cilia DEGs identified, 50 genes were downregulated and 11 genes were upregulated. These cilia genes are involved in cilium assembly, protein trafficking to the cilium, intraflagellar transport (IFT), cellular signaling like polarity patterning, and Hedgehog signaling pathway. This suggests that the C2 domain of CC2D2A plays a critical role in cilia assembly and molecular signaling hosted in cilia for cellular homeostasis. Taken together, the missense mutations in the C2 domain of CC2D2A seen in JBTS might have affected cilia-mediated signaling in neurons of the retina and brain. [ABSTRACT FROM AUTHOR]

Since the evolution of the aerobic metabolism, reactive oxygen species (ROS) have represented significant challenges to diverse life forms. In recent decades, increasing knowledge has revealed a dual role for ROS in cell physiology, showing they serve as a major source of cellular damage while also functioning as important signaling molecules in various biological processes. Our understanding of ROS homeostasis and ROS-mediated cellular signaling pathways has presumed that they are ancient and highly conserved mechanisms shared by most organisms. However, emerging evidence highlights the complexity and plasticity of ROS signaling, particularly in animals that have evolved in extreme environments. In this review, we focus on ROS generation, antioxidative systems and the main signaling pathways that are influenced by ROS. In addition, we discuss ROS's responsive transcription regulation and how it may have been shaped over the course of evolution. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) refers to a condition that often has 'poly' liquid containing sacks around ovaries. It affects reproductive-aged females giving rise to menstrual and related reproductive issues. PCOS is marked by hormonal imbalance often resulting in hyperandrogenism. Inflammation is now considered a central manifestation of this disease with several inflammatory biomarkers such as TNF-α, C-reactive protein and Interleukins-6/18 found to be particularly elevated in PCOS patients. Diagnosis is often late, and MRI-based diagnosis, along with blood-based analyses, are still the best bet for a definitive diagnosis. Radiomics also offers several advantages and should be exploited to the maximum. The mechanisms of PCOS onset and progression are not very well known but pituitary dysfunction and elevated gonadotrophin releasing hormone resulting in high levels of luteinizing hormone are indicative of an activated hypothalamic-pituitary-ovarian axis in PCOS. A number of studies have also identified signaling pathways such as PI3K/Akt, NF-κB and STAT in PCOS etiology. The links of these signaling pathways to inflammation further underline the importance of inflammation in PCOS, which needs to be resolved for improving patient outcomes. [ABSTRACT FROM AUTHOR]

The rapid development of the COVID-19 pandemic resulted in a closer analysis of cell functioning during β-coronavirus infection. This review will describe evidence for COVID-19 as a syndrome with a strong, albeit still underestimated, mitochondrial component. Due to the sensitivity of host mitochondria to coronavirus infection, SARS-CoV-2 affects mitochondrial signaling, modulates the immune response, modifies cellular energy metabolism, induces apoptosis and ageing, worsening COVID-19 symptoms which can sometimes be fatal. Various aberrations across human systems and tissues and their relationships with mitochondria were reported. In this review, particular attention is given to characterization of multiple alterations in gene expression pattern and mitochondrial metabolism in COVID-19; the complexity of interactions between SARS-CoV-2 and mitochondrial proteins is presented. The participation of mitogenome fragments in cell signaling and the occurrence of SARS-CoV-2 subgenomic RNA within membranous compartments, including mitochondria is widely discussed. As SARS-CoV-2 severely affects the quality system of mitochondria, the cellular background for aberrations in mitochondrial dynamics in COVID-19 is additionally characterized. Finally, perspectives on the mitigation of COVID-19 symptoms by affecting mitochondrial biogenesis by numerous compounds and therapeutic treatments are briefly outlined.

Abstract Bladder cancer (BC) accounts for roughly 3% of all cancer diagnoses in developed countries. The prognosis could be improved significantly if the cancer is detected and classified as either muscle‐invasive bladder cancer (MIBC) or non‐muscle‐invasive bladder cancer (NMIBC) as promptly as possible. A potential ray of hope for the treatment of BC has emerged with the rapid development of nanomedicine and microRNAs (miRNAs), which promise to have fewer adverse effects, more tumor‐inhibitory effects, and decreased drug resistance. The complex interplay between hereditary and environmental variables is the root cause of this malignancy. Gene expression can be regulated by miRNAs, which are small, non‐coding RNAs that can either prevent the translation of protein‐coding genes or cleave RNA transcripts at certain locations. Elevated genomics has enabled a more extensive investigation of miRNAs whose expression is considerably different in BC patients compared to healthy volunteers or between BC tumor tissues and peripheral tissues. miRNAs have recently been discovered to be important regulators of BC cell carcinogenicity. Inaccurate diagnoses and prolonged treatment delays are more likely to occur due to the current diagnostic process such as lack of sensitivity and specificity and poor image quality. Patients now have access to a plethora of treatment options, including but not limited to surgery, chemotherapy, immunotherapy, gene therapy, and other innovative medicines, and in some cases, combination therapies. BC is one of the deadliest and most disabling malignancies affecting the urinary tract. Cancer of the urinary bladder has a terrible propensity for being fatal. BC is an intricate illness whose development can be affected by multiple parameters. Standard treatments for BC increase prognosis and survival, although recurrence is a major concern for patients. miRNAs are naturally occurring, small RNA molecules that have been linked to cancer through their expression being dysregulated. miRNAs modulate many cellular activities including proliferation, migration, differentiation, and apoptosis. MiRNA dysregulation is recognized in BC, and miRNAs are used as diagnostic and prognostic indicators. However, this manuscript discusses the recent progress made in nanomedicine and the function of miRNAs in the pathogenesis and targeted therapy of BC.

Abstract Background Cell cycle regulation influences the proliferation of granulosa cells and affects many processes related to ovarian folliclular growth and ovulation. Abnormal regulation of the cell cycle can lead to many diseases within the ovary. The aim of this study was to describe the expression profile of genes within granulosa cells, which are related to the formation of the cytoskeleton, organization of cell organelles inside the cell, and regulation of cell division. Established in vitro primary cultures from porcine ovarian follicle granulosa cells were maintained for 48, 96, 144 h and evaluated via microarray expression analysis. Results Analyzed genes were assigned to 12 gene ontology groups "actin cytoskeleton organization", "actin filament organization", "actin filament—based process", "cell—matrix adhesion", "cell—substrate adhesion", "chromosome segregation", "chromosome separation", "cytoskeleton organization", "DNA integrity checkpoint", "DNA replication initiation", "organelle fision", "organelle organization". Among the genes with significantly changed expression, those whose role in processes within the ovary are selected for consideration. Genes with increased expression include (ITGA11, CNN1, CCl2, TPM2, ACTN1, VCAM-1, COL3A1, GSN, FRMD6, PLK2). Genes with reduced expression inlcude (KIF14, TACC3, ESPL1, CDC45, TTK, CDC20, CDK1, FBXO5, NEK2—NIMA, CCNE2). For the results obtained by microarray expressions, quantitative validation by RT-qPCR was performed. Conclusions The results indicated expression profile of genes, which can be considered as new molecular markers of cellular processes involved in signaling, cell structure organization. The expression profile of selected genes brings new insight into regulation of physiological processes in porcine follicular granulosa cells during primary in vitro culture.

Artemisinin, a traditional Chinese medicine with remarkable antimalarial activity. In recent years, studies demonstrated that artemisinin and its derivatives (ARTs) showed anti-inflammatory and immunoregulatory effects. ARTs have been developed and gradually applied to treat autoimmune and inflammatory diseases. However, their role in the treament of patients with autoimmune and inflammatory diseases in particular is less well recognized. This review will briefly describe the history of ARTs use in patients with autoimmune and inflammatory diseases, the theorized mechanisms of action of the agents ARTs, their efficacy in patients with autoinmmune and inflammatory diseases. Overall, ARTs have numerous beneficial effects in patients with autoimmune and inflammatory diseases, and have a good safety profile.

Macrophages activation and inflammatory response play crucial roles in intracranial aneurysm (IA) formation and progression. The outcome of ruptured IA is considerably poor, and the mechanisms that trigger IA progression and rupture remain to be clarified, thereby developing effective therapy to prevent subarachnoid hemorrhage (SAH) become difficult. Recently, climbing evidences have been expanding our understanding of the macrophages relevant IA pathogenesis, such as immune cells population, inflammatory activation, intra-/inter-cellular signaling transductions and drug administration responses. Crosstalk between macrophages disorder, inflammation and cellular signaling transduction aggravates the devastating consequences of IA. Illustrating the pros and cons mechanisms of macrophages in IA progression are expected to achieve more efficient treatment interventions. In this review, we summarized the current advanced knowledge of macrophages activation, infiltration, polarization and inflammatory responses in IA occurrence and development, as well as the most relevant NF-κB, signal transducer and activator of transcription 1 (STAT1) and Toll-Like Receptor 4 (TLR4) regulatory signaling modulation. The understanding of macrophages regulatory mechanisms is important for IA patients' clinical outcomes. Gaining insight into the macrophages regulation potentially contributes to more precise IA interventions and will also greatly facilitate the development of novel medical therapy. [ABSTRACT FROM AUTHOR]

Ether-lipids (EL) are specific lipids bearing a characteristic sn- 1 ether bond. Depending on the ether or vinyl-ether nature of this bond, they are present as alkyl- or alkenyl-EL, respectively. Among EL, alkenyl-EL, also referred as plasmalogens in the literature, attract most of the scientific interest as they are the predominant EL species in eukaryotic cells, thus less is known about alkyl-EL. EL have been implicated in various signaling pathways and alterations in their quantity are frequently observed in pathologies such as neurodegenerative and cardiovascular diseases or cancer. However, it remains unknown whether both alkyl- and alkenyl-EL play the same roles in these processes. This review summarizes the roles and mechanisms of action of EL in cellular signaling and tries to discriminate between alkyl- and alkenyl-EL. We also focus on the involvement of EL-mediated alterations of cellular signaling in diseases and discuss the potential interest for EL in therapy. • Ether-lipids are specific lipids existing either as alkyl- or alkenyl-ether-lipids. • Ether-lipids have been involved in the regulation of cellular signaling. • In various pathologies, quantities of ether-lipids are altered. • It remains unknown whether alkyl- and alkenyl-ether-lipids play differential roles. [ABSTRACT FROM AUTHOR]

Synchronized contractions of cardiomyocytes within the heart are tightly coupled to electrical stimulation known as excitation-contraction coupling. Calcium plays a key role in this process and dysregulated calcium handling can significantly impair cardiac function and lead to the development of cardiomyopathies and heart failure. Here, we describe a method and analytical technique to study myofilament-localized calcium signaling using the intensity-based fluorescent biosensor, RGECO-TnT. Dilated cardiomyopathy is a heart muscle disease that negatively impacts the heart's contractile function following dilatation of the left ventricle. We demonstrate how this biosensor can be used to characterize 2D hiPSC-CMs monolayers generated from a healthy control subject compared to two patients diagnosed with dilated cardiomyopathy. Lastly, we provide a step-by-step guide for single-cell data analysis and describe a custom Transient Analysis application, specifically designed to quantify features of calcium transients. All in all, we explain how this analytical approach can be applied to phenotype hiPSC-CM behaviours and stratify patient responses to identify perturbations in calcium signaling. [ABSTRACT FROM AUTHOR]

Muscular dystrophy exerts significant and dramatic impacts on affected patients, including progressive muscle wasting leading to lung and heart failure, and results in severely curtailed lifespan. Although the focus for many years has been on the dysfunction induced by the loss of function of dystrophin or related components of the striated muscle costamere, recent studies have demonstrated that accompanying pathologies, particularly muscle fibrosis, also contribute adversely to patient outcomes. A significant body of research has now shown that therapeutically targeting these accompanying pathologies via their underlying molecular mechanisms may provide novel approaches to patient management that can complement the current standard of care. In this review, we discuss the interplay between muscle fibrosis and muscular dystrophy pathology. A better understanding of these processes will contribute to improved patient care options, restoration of muscle function, and reduced patient morbidity and mortality. [ABSTRACT FROM AUTHOR]

Autosomal dominant leukodystrophy (ADLD) is an ultra-rare, slowly progressive, and fatal neurodegenerative disorder associated with the loss of white matter in the central nervous system (CNS). Several years after its first clinical description, ADLD was found to be caused by coding and non-coding variants in the LMNB1 gene that cause its overexpression in at least the brain of patients. LMNB1 encodes for Lamin B1, a protein of the nuclear lamina. Lamin B1 regulates many cellular processes such as DNA replication, chromatin organization, and senescence. However, its functions have not been fully characterized yet. Nevertheless, Lamin B1 together with the other lamins that constitute the nuclear lamina has firstly the key role of maintaining the nuclear structure. Being the nucleus a dynamic system subject to both biochemical and mechanical regulation, it is conceivable that changes to its structural homeostasis might translate into functional alterations. Under this light, this review aims at describing the pieces of evidence that to date have been obtained regarding the effects of LMNB1 overexpression on cellular morphology and functionality. Moreover, we suggest that further investigation on ADLD morpho-functional consequences is essential to better understand this complex disease and, possibly, other neurological disorders affecting CNS myelination. [ABSTRACT FROM AUTHOR]

With the increasing prevalence of type 2 diabetes and fatty liver disease, there is still an unmet need to better treat hyperglycemia and hyperlipidemia. Here, we identify isthmin-1 (Ism1) as an adipokine and one that has a dual role in increasing adipose glucose uptake while suppressing hepatic lipid synthesis. Ism1 ablation results in impaired glucose tolerance, reduced adipose glucose uptake, and reduced insulin sensitivity, demonstrating an endogenous function for Ism1 in glucose regulation. Mechanistically, Ism1 activates a PI3K-AKT signaling pathway independently of the insulin and insulin-like growth factor receptors. Notably, while the glucoregulatory function is shared with insulin, Ism1 counteracts lipid accumulation in the liver by switching hepatocytes from a lipogenic to a protein synthesis state. Furthermore, therapeutic dosing of recombinant Ism1 improves diabetes in diet-induced obese mice and ameliorates hepatic steatosis in a diet-induced fatty liver mouse model. These findings uncover an unexpected, bioactive protein hormone that might have simultaneous therapeutic potential for diabetes and fatty liver disease.

Successful pregnancy depends on precise molecular regulation of uterine physiology, especially during the menstrual cycle. Deregulated oxidative stress (OS), often influenced by inflammatory changes but also by environmental factors, represents a constant threat to this delicate balance. Oxidative stress induces a reciprocally regulated nuclear factor erythroid 2-related factor 2/peroxisome proliferator-activated receptor-gamma (Nrf2/PPARγ) pathway. However, increased PPARγ activity appears to be a double-edged sword in endometrial physiology. Activated PPARγ attenuates inflammation and attenuates OS to restore redox homeostasis. However, it also interferes with physiological processes during the menstrual cycle, such as hormonal signaling and angiogenesis. This review provides an elucidation of the molecular mechanisms that support the interplay between PPARγ and OS. Additionally, it offers fresh perspectives on the Nrf2/PPARγ pathway concerning endometrial receptivity and its potential implications for infertility.