Overexpression of peroxiredoxin 6 in bone marrow-derived mesenchymal stem cells amplifies their in vivo effect on bronchopulmonary dysplasia by increasing mesencephalic astrocyte-derived neurotrophic factor secretion.

Mechanistic investigation of quercetin (an active component of RAS-RH) in modulating radiation-induced coronary microvascular dysfunction via the TCs-ECs crosstalk pathway.

Epidermal growth factor receptor promotes diabetic retinal fibrogenesis via YAP-CCN2-dependent manner.

Prostanoids in Liver Repair and Regeneration: Biosynthesis, Receptors, and Intercellular Communication.

Abstract Background The survival and function of three-dimensional tissues critically depend on the establishment of a functional vascular network that ensures oxygen and nutrient supply and waste removal. Insufficient vascularization leads to hypoxia, metabolic stress, and cell death, making angiogenesis a fundamental requirement for successful tissue regeneration. This requirement is particularly evident in highly vascularized tissues such as bone, where vascular networks closely regulate tissue metabolism and repair. Methods Human adipose-derived mesenchymal stem cells (ASCs) were genetically modified to overexpress fibroblast growth factor 2 (FGF-2), a key regulator of angiogenesis. The angiogenic potential of these cells and the paracrine effects of their conditioned medium were subsequently evaluated, together with their effects on osteogenic differentiation to assess functional specificity. Results Overexpression of FGF-2 in ASCs enhanced endothelial cell migration and tube formation via paracrine mechanisms, in which elevated secretion of VEGFA and other angiogenic factors acted synergistically to promote angiogenesis. In contrast, osteogenic differentiation of ASCs was significantly inhibited by FGF-2 overexpression. Notably, FGFR2 expression, the receptor for FGF-2, was selectively downregulated during osteogenic induction, suggesting that sustained FGF-2 signaling preferentially interferes with FGFR-mediated pathways associated with osteogenic maturation rather than with early proliferative responses. Conclusion Our results demonstrate that FGF-2–overexpressing ASCs function not as osteogenic effector cells but as a potent paracrine platform for angiogenesis. Their conditioned medium, enriched with FGF-2 and synergistic angiogenic factors, supports vascular network formation and indirectly enhances the regenerative microenvironment, highlighting its potential as a cell-free strategy for tissue regeneration.

Cancer-associated fibroblasts (CAFs) are associated with tumor progression and drug resistance. Here, we investigated the mechanisms underlying the cross-talk between CAFs and tumor cells in non-small cell lung cancer (NSCLC). In NSCLC cell lines with EML4-ALK fusions, we observed substantial CAF-mediated drug resistance to clinically used inhibitors of the tyrosine kinase ALK. Array-based cytokine profiling of CAF-derived conditioned medium indicated that a major contributor to the phenomenon was the secreted growth factor HGF, and blocking its receptor MET overcame paracrine resistance to ALK inhibition. However, cell-selective labeling of the proteome in cocultures also revealed an equally important contribution by the fibronectin-integrin pathway, specifically integrin β1, which was confirmed through pharmacological inhibition and cell-specific silencing or knockout. Concurrent targeting of MET and integrin signaling effectively abrogated ALK inhibitor resistance in EML4-ALK+ NSCLC cells cocultured with CAFs. Moreover, the combination of the ALK inhibitor alectinib with the MET inhibitor capmatinib and/or the integrin inhibitor cilengitide was more effective than single-agent treatment in suppressing tumor growth in allografted mice. The findings illustrate a previously unappreciated complex nature of concurrent paracrine and juxtacrine mechanisms of CAF-driven resistance that may inform the development of more effective therapeutic approaches.

BackgroundMicroglia are emerging as critical regulators of neurovascular function in health and Alzheimer’s disease (AD), yet their interactions with the human neurovascular unit (NVU), particularly brain endothelial cells, remain incompletely understood. Currentin vitroNVU platforms typically exclude microglia and lack perfusable vascular networks with physiologically relevant architecture. Here, we established complementary two-dimensional (2D) and three-dimensional (3D) NVU models to investigate microglia-endothelial and microglia-neurovascular interactions.MethodsHuman induced pluripotent stem cell derived-neurons (iNs), astrocytes (iAs), and microglia-like cells (iMGLs) were incorporated into a soft-lithography based engineered microvessel system to establish a multicellular neuroimmune-vascular model. To specifically evaluate iMGL-endothelial cell (EC) interactions, iMGL were co-cultured with primary human brain microvascular endothelial cells (HBMECs) and junctional protein localization was evaluated using immunofluorescence. The barrier integrity of engineered microvessels containing iMGL was evaluated using dextran permeability. Our 2D and 3D systems were stimulated with tumor necrosis factor-α (TNFα) to evaluate whether iMGL would promote or attenuate EC inflammation and barrier breakdown.ResultsIncorporation of iNs, iAs, and iMGLs into a perfusable vascular model enabled a more complete representation of NVU cellular diversity and promoted neuronal health. In monolayer co-culture with iMGL, HBMECs enhanced the junctional localization of tight and adherens junction proteins through both contact-dependent and paracrine mechanisms. Following an inflammatory challenge, iMGLs reduced endothelial inflammatory activation, suggesting a protective role in response to AD-relevant inflammatory conditions. Finally, when embedded in 3D collagen matrices surrounding perfusable endothelialized lumen networks, iMGLs reduced dextran permeability and preserved endothelial barrier integrity following TNFα challenge.ConclusionsTogether, these findings establish a 3D perfusable neuroimmune-vascular model that enables the dissection of microglial contributions to neurovascular function in health and disease.

Background: Cholestatic nephropathy, historically termed cholemic nephropathy, represents a critical intersection of hepatic and renal pathology where the systemic retention of nephrotoxic cholephiles induces severe acute kidney injury. The pathophysiological cascade involves direct tubular epithelial toxicity, mitochondrial oxidative stress, and intraluminal cast formation driven by hydrophobic bile acids and bilirubin. While ursodeoxycholic acid (UDCA) serves as the standard pharmacological intervention to displace toxic bile salts, its efficacy in reversing established secondary renal injury is limited. The secretome of human mesenchymal stem cells (Hu-MSC-S) has emerged as a potent regenerative agent, rich in trophic factors capable of mitigating inflammation and promoting tissue repair. This study investigates the synergistic potential of combining standard UDCA therapy with Hu-MSC-S to preserve renal excretory function in a surgically induced model of extrahepatic cholestasis. Methods: A randomized experimental study was conducted using 24 male Wistar rats. Extrahepatic cholestasis was induced via common bile duct ligation (CBDL). Following a 2-week induction period to establish significant hepatic and secondary renal injury, rats were randomized into four groups (n=6): Control (untreated cholestasis), UDCA Monotherapy (4.5 mg/200g body weight orally), Hu-MSC-S Monotherapy (0.2 ml/kg intraperitoneally), and combination therapy (UDCA + Hu-MSC-S). Treatments were administered weekly for four weeks. Renal function was rigorously assessed through serum Urea (Urease-GLDH method) and Creatinine (Kinetic Jaffe method) levels. Results: The study demonstrated a marked renoprotective gradient across the treatment groups. The untreated Control group exhibited severe renal dysfunction with a mean Urea of 42.60 mg/dL and Creatinine of 3.18 mg/dL. Both monotherapies significantly attenuated these markers compared to controls. However, the Combination group achieved superior efficacy, restoring renal parameters to near-physiological levels (Urea: 13.08 mg/dL; Creatinine: 1.32 mg/dL). Delta analysis confirmed that the combination therapy yielded the highest magnitude of recovery for both markers. Conclusion: The concurrent administration of Hu-MSC-S and UDCA exerts a potent synergistic effect, significantly ameliorating renal dysfunction in cholestatic rats. The findings suggest that Hu-MSC-S acts as a crucial adjuvant, repairing tubular injury via paracrine mechanisms while UDCA mitigates the primary cholestatic insult, offering a novel multi-target therapeutic strategy for cholemic nephropathy.

hPMSC-derived Exosomal miR-26-5p modulates macrophage polarization for liver repair in DILI via PTEN/mTOR signaling.

Adipose tissue, beyond its role as a fat storage depot, functions as an endocrine organ, secreting signaling molecules systemically and via paracrine mechanisms (particularly in perivascular and ectopic fat). These diverse functions are crucial for regulating metabolic and cardiovascular health. The circadian clock, an internal ~24-h biological rhythm, orchestrates physiological processes to adapt to environmental cycles (e.g., light, temperature, food). This involves linking gene transcription/translation events to the external environment. Recent studies demonstrate circadian expression patterns in adipose tissue for various genes and metabolic pathways. Disrupted circadian rhythms are implicated in adipose tissue and metabolic dysfunction. Understanding adipose tissue circadian mechanisms may provide strategies to mitigate metabolic and associated cardiovascular disease risk. This review summarizes recent findings on the relationship between circadian rhythms and adipose tissue metabolism, explores how an adipose clock contributes to the pathogenesis of metabolic diseases, and discusses potential therapeutic approaches targeting the adipose tissue clock.

EGFR-mutant lung adenocarcinomas (LUADs) that are vulnerable to the EGFR antagonist Osimertinib (Osi) eventually relapse owing in part to the emergence of drug tolerant persister (DTP) cells that arise through epigenetic mechanisms. Intra-tumoral DTP cells can herald a worse clinical outcome, but the way in which DTP cells influence LUAD progression remains unclear. Osi-resistant (OR) cells exhibit typical DTP cell features, including a propensity to undergo senescence and epithelial-to-mesenchymal transition (EMT), which can activate heightened secretory states. Therefore, we postulated that OR cells influence LUAD progression through paracrine mechanisms. To test this hypothesis, we utilized congenic pairs of EGFR-mutant LUAD cell lines in which drug naive (DN) cells were rendered OR by chronic exposure to escalating doses of Osi. Co-cultured in vitro or co-injected into mice, paracrine signals from OR cells enhanced the growth and metastatic properties of DN cells. EMT and senescence activated non-overlapping secretomes, and OR cells governed DN cells by undergoing EMT but not senescence. Mechanistically, Osi rapidly increased TGFβ2 levels to initiate EMT, which triggered a Golgi remodeling process that accelerated the biogenesis and anterograde trafficking of secretory vesicles. The pro-tumorigenic activity of OR cells was diminished by depletion of EMT-dependent secreted proteins or the EMT-activating transcription factor ZEB1. These findings identify paracrine mechanisms by which OR cells drive LUAD progression.

Astrocytic HIF-1α/VEGF induces endothelial PI3K/Akt activation to accelerate post-ischemic angiogenesis upon LCN2 inhibition.

The biomechanical properties of the meniscus are involved in the pathogenesis of knee osteoarthritis (KOA), however, the biological role of a degenerated meniscus in KOA is unclear. This study examined the effects of degenerated meniscal tissue on articular chondrocytes using human meniscal tissues and articular chondrocytes obtained from 13 patients with KOA. Co-culture model and supernatant cell culture model were used and RNA sequencing, RT-qPCR and cell immunofluorescence staining were performed. The key finding of this study is that human degenerated meniscus alters expressions of OA-related genes and promotes productions of COX2 and MMP3 proteins in articular chondrocytes from KOA patients through paracrine effect. These findings suggest that degenerated human meniscal tissue induces inflammatory and degenerative changes in articular chondrocytes through a paracrine mechanism, potentially contributing to KOA pathogenesis.

CXCL3, a member of the CXC chemokine family, has been increasingly implicated in the progression of various cancers, including hepatocellular carcinoma, due to its role in immune and inflammatory responses within the tumor microenvironment. This study aimed to investigate the expression and function of CXCL3 in liver cancer and to elucidate its underlying mechanisms. A combination of bioinformatics analysis, ELISA, RT-qPCR, immunohistochemistry, in vitro cell assays, and in vivo nude mouse models was employed to assess CXCL3 expression and function. The results showed that CXCL3 was significantly upregulated in hepatocellular carcinoma tissues and associated with reduced overall survival in patients. It promoted the proliferation, colony formation, and migration of liver cancer cells (Bel-7402, HepG2, and SMMC-7721) via exogenous, autocrine, and paracrine mechanisms, and recruited tumor-associated macrophages, neutrophils, and fibroblasts into the tumor microenvironment. Mechanistically, CXCL3 activated the PI3K/AKT/mTOR pathway by upregulating PI3K, p-PI3K, AKT, p-AKT, mTOR, and p-mTOR, while the mTOR inhibitor Torin 1 reversed these effects. Gene set enrichment analysis showed enrichment in immune-related pathways, including Toll-like receptor and chemokine signaling. In vivo, CXCL3 overexpression significantly promoted tumor growth in nude mice. These findings suggest CXCL3 facilitates liver cancer progression through tumor microenvironment modulation and PI3K/AKT/mTOR pathway activation.

IntroductionAdipose-derived stem cell-conditioned medium (ASC-CM) is promising for cardiac repair via paracrine mechanisms. However, variability in efficacy limits its clinical translation. We investigated whether preconditioning human ASC with butyrate (ASC-BA-CM) enhanced its paracrine potency and improved in vitro and in vivo outcomes.MethodRNA-sequencing of human ASCs treated with butyrate was performed to characterize transcriptomic changes. CM was collected and analyzed via cytokine/chemokine arrays. Wound healing assays using human umbilical vein endothelial cells (HUVECs), with and without THP-1 macrophage co-culture, were performed to evaluate endothelial repair and its correlations with secreted factors. In vivo angiogenesis was assessed using a sponge implantation model, and myocardial perfusion was measured in a rat myocardial infarction model using single-photon emission computed tomography/computed tomography (SPECT/CT) thallium-201 imaging.ResultsButyrate preconditioning upregulated angiogenesis- and immune-related genes, including CXCL8, SOD2, and TGM2. It increased IL-10, CXCL5, and MMP-1 secretion. In vitro, BA-preconditioned ASC-CM enhanced HUVEC wound closure, which was improved by co-culture with THP-1 macrophages and negatively correlated with TGFb3 and TIMP-2 levels. In vivo, ASC-BA-CM promoted vascularization and macrophage accumulation in sponges and significantly improved myocardial perfusion by approximately 32 % compared with controls.ConclusionsButyrate preconditioning enhanced the paracrine activity of ASC-CM and was associated with improved myocardial perfusion in a rat model. These findings suggest that butyrate may augment the ASC secretome function. Potential mechanisms such as endothelial repair, angiogenesis, and immune modulation remain hypothetical and require further validation in future studies.

Endothelial Lon protease 1 facilitates the redox balance to prevent glomerulosclerosis by acting on superoxide dismutase 2 ubiquitination

PurposeEffective intercellular communication among lens epithelial cells (LECs) is essential for lens homeostasis, and its disruption has been implicated in cataract formation. This study investigates the mechanisms of calcium (Ca²⁺) wave propagation in the human lens epithelium, focusing on the respective roles of gap-junctional coupling and ATP-mediated paracrine signaling.MethodsWe performed multicellular Ca²⁺ imaging on human postoperative anterior lens capsule preparations obtained from cataractous lenses during cataract surgery which retained intact monolayers containing viable LECs. Mechanically induced Ca²⁺ waves were recorded, and the contribution of specific signaling pathways was evaluated by pharmacological intervention using apyrase (an ATP-hydrolyzing enzyme) and carbenoxolone (CBX; a gap-junctional blocker). To interpret the experimental results, we developed a biophysically detailed computational model of the LEC monolayer, incorporating intracellular Ca²⁺ dynamics, gap-junctional IP₃/Ca²⁺ diffusion, and extracellular ATP signaling.ResultsApyrase moderately reduced the spatial extent, amplitude, and duration of Ca²⁺ waves without affecting propagation speed. In contrast, CBX significantly suppressed wave transmission, limiting activation to cells directly adjacent to the stimulation site. Simulations reproduced key experimental features and indicated that neither pure gap-junctional nor purely paracrine signaling mechanisms alone could explain the observed dynamics. Instead, a hybrid mechanism combining gap-junctional communication and partially regenerative ATP release was required.ConclusionsOur results highlight the cooperative roles of gap-junctional and ATP-based paracrine signaling in mediating mechanically induced Ca²⁺ wave propagation in the human lens epithelium. This dual-pathway mechanism may be critical for coordinated cellular responses that support physiological processes such as ion homeostasis and transparency maintenance in the human lens.

The use of multipotent stem cells opens new possibilities in various fields of medicine, including urology. This article provides a detailed overview of experimental and clinical studies demonstrating the efficacy of multipotent stem cells in the treatment of urologic diseases. Multipotent stem cells have been shown to reduce the severity of renal failure, improve urinary incontinence, and alleviate both organic and functional bladder disorders, ischemia–reperfusion injuries of the testes, erectile dysfunction, and penile enlargement. Moreover, they have proven effective in Peyronie disease and ischemic priapism. New tissue-engineering approaches for cystoplasty and urethral stricture repair are described, in which multipotent stem cells are adsorbed onto various graft materials before surgery. The high therapeutic efficacy of cell therapy is most likely associated with its ability to stimulate regeneration and angiogenesis, restore microcirculation and innervation, inhibit inflammation and apoptosis, and reduce tissue injury and fibrosis. Only a small fraction of implanted multipotent stem cells remain viable and differentiate into smooth muscle and endothelial cells. The primary effect of multipotent stem cells is most likely mediated by paracrine mechanisms. No severe adverse effects have been reported following the clinical application of multipotent stem cells.

Abstract Neuronal activity and synchrony in both normal and pathological states are regulated by excitatory and inhibitory synaptic inputs, determined by ion channel permeability across the cell membrane. This study investigates neuron-glioma cross-talk in chloride flux and the role of chloride, the most abundant neuronal anion, in influencing neuronal excitability and glioblastoma (GBM) pathophysiology. We hypothesized that GBM’s aggressive proliferative and invasive phenotype is linked to chloride dysregulation and that inhibiting glioma chloride flux could reduce tumor proliferation and glioma-induced neuronal hyperexcitability. The direct effects of chloride flux on glioma growth and invasion were tested using optogenetic stimulation of chloride opsin-expressing glioma cells both in vitro and implanted in vivo in patient-derived xenograft (PDX) mice. To explore chloride cross-talk mechanisms between neurons and glioma cells, we performed single-nucleus RNA sequencing (sNuc-seq) of GBM-neuron co-cultures, analyzing 54,000 cells, and revealed the upregulation of genes involved in chloride homeostasis, including the voltage-gated ClC-3 chloride channel and the sodium-potassium-chloride cotransporter 1 (NKCC1). Mass spectrometry-based proteomic analysis of culture supernatant was performed to identify mechanistic targets and paracrine factors mediating chloride transfer. Light-activated chloride pumping into glioma cells significantly reduced tumor proliferation in vitro and in vivo, underscoring the link between intracellular chloride concentration and tumor growth. sNuc-seq also showed upregulation of NKCC1 and the ligand-gated chloride channel GABAA receptor in tumor-associated neurons co-cultured with NKCC1-overexpressing glioma cells, suggesting shared chloride signaling mechanisms in the tumor microenvironment. Proteomic profiling of conditioned media identified glioma-derived MK2 (MAPKAPK2) as a driver of neuronal NKCC1 upregulation and chloride dysregulation. Pretreatment of GBM cells with the MK2 inhibitor ralimetinib restored chloride balance and reduced neuronal hyperexcitability. Collectively, these findings reveal a paracrine mechanism of chloride transfer between glioma cells and neurons, highlighting chloride signaling as a novel therapeutic target to inhibit neuronal hyperexcitability and tumor proliferation in glioblastoma multiforme (GBM).

Abstract Glioblastoma (GBM) is the most aggressive primary brain tumor with limited treatment options and a dismal prognosis. Increasing evidence highlights reactive astrocytes (RAs) as active participants in the tumor microenvironment, where they acquire pro-tumorigenic transcriptional states that support glioma growth. However, the specific upstream mechanisms driving RA activation and their contribution to GBM malignancy remain unclear. In this study, we identify glioma-derived extracellular matrix (ECM), particularly collagen-I (COL I), as a key regulator of astrocyte reactivity. Using syngeneic mouse glioma models, we performed RNA-Scope and immunofluorescence analyses for GFAP and CHI3L1 to assess RA expression and spatial distribution. We observed that COL I-high tumors exhibited robust RA enrichment at the tumor border and contralateral cortex, whereas COL I-low tumors showed RA localization primarily within the tumor core. Bulk RNA sequencing of 95 (84 IDH-WT and 14 IDH1-Mut) clinical glioma samples, stratified by IDH-1 and COL I expression, revealed significant upregulation of RA-associated genes linked to the pro-tumorigenic Ast3 transcriptional state, including CHI3L1, CCL2, CHI3L2, C1R, IL1R1, ADAM12, SPOCD1, S100A11, SERPING1, and S100A10. Spatial transcriptomics (10X Visium HD) on a subset of the same glioma specimens further confirmed enrichment of RA-Ast3 signatures in COL I-high tumors, with co-localized RA clusters both within and surrounding COL I-rich regions. These findings support a model of transcriptional reprogramming of astrocytes in response to tumor-derived ECM. To explore potential paracrine mechanisms, we employed a non-contact Transwell co-culture system using glioma cells and normal mouse brain slices. Slices exposed to COL I-high glioma cells exhibited significantly increased GFAP expression compared to those exposed to COL I-low cells, indicating indirect activation of astrocytes via secreted factors. Collectively, our findings position reactive astrocytes as key mediators of GBM progression and identify collagen-I as a potent upstream modulator. These results suggest promising therapeutic targets aimed at disrupting glioma–astrocyte communication to inhibit tumor growth.