Search Results (278)

Forty per cent of major depression patients are resistant to antidepressant medication. Thus, it is necessary to search for alternative treatments. Melatonin (N-acetyl-5-hydroxytryptamine) enhances neurogenesis and neuronal survival in the adult mouse hippocampal dentate gyrus. Additionally, melatonin stimulates the activity of Ca²⁺/Calmodulin-dependent Kinase II (CaMKII), promoting dendrite formation and neurogenic processes in human olfactory neuronal precursors and rat organotypic cultures. Similarly, ketamine, an N-methyl-D-aspartate receptor (NMDAR) antagonist, modulates CaMKII activity. Importantly, co-treatment of low doses of ketamine (10⁻⁷ M) in combination with melatonin (10⁻⁷ M) produces additive effects on neurogenic responses in olfactory neuronal precursors. Importantly, enhanced neurogenic responses are produced by conventional antidepressants like ISSRs. The goal of this study was to investigate whether hippocampal CaMKII participates in the signaling pathway elicited by combining doses of melatonin with ketamine acutely administered to mice, 30 min before being subjected to the forced swimming test. The results showed that melatonin, in conjunction with ketamine, significantly enhances CaMKII activation and changes its subcellular distribution in the dentate gyrus of the hippocampus. Remarkably, melatonin causes nuclear translocation of the active form of CaMKII. Luzindole, a non-selective MT₁ and MT₂ receptor antagonist, abolished these effects, suggesting that CaMKII is downstream of the melatonin receptor pathway that causes the antidepressant-like effects. These findings provide molecular insights into the combined effects of melatonin and ketamine on neuronal plasticity-related signaling pathways and pave the way for combating depression using combination therapy. Full article

Male-factor infertility accounts for approxiamately half of all infertility cases globally, yet therapeutic options remain limited for individuals with no retrievable spermatozoa, such as those with non-obstructive azoospermia (NOA). In recent years, artificial gametogenesis has emerged as a promising avenue for fertility restoration, driven by advances in two complementary strategies: organotypic in vitro spermatogenesis (IVS), which aims to complete spermatogenesis ex vivo using native testicular tissue, and in vitro gametogenesis (IVG), which seeks to generate male gametes de novo from pluripotent or reprogrammed somatic stem cells. To evaluate the current landscape and future potential of these approaches, a narrative, semi-systematic literature search was conducted in PubMed and Scopus for the period January 2010 to February 2025. Additionally, landmark studies published prior to 2010 that contributed foundational knowledge in spermatogenesis and testicular tissue modeling were reviewed to provide historical context. This narrative review synthesizes multidisciplinary evidence from cell biology, tissue engineering, and translational medicine to benchmark IVS and IVG technologies against species-specific developmental milestones, ranging from rodent models to non-human primates and emerging human systems. Key challenges—such as the reconstitution of the blood–testis barrier, stage-specific endocrine signaling, and epigenetic reprogramming—are discussed alongside critical performance metrics of various platforms, including air–liquid interface slice cultures, three-dimensional organoids, microfluidic “testis-on-chip” devices, and stem cell-derived gametogenic protocols. Particular attention is given to clinical applicability in contexts such as NOA, oncofertility preservation in prepubertal patients, genetic syndromes, and reprocutive scenarios involving same-sex or unpartnered individuals. Safety, regulatory, and ethical considerations are critically appraised, and a translational framework is outlined that emphasizes biomimetic scaffold design, multi-omics-guided media optimization, and rigorous genomic and epigenomic quality control. While the generation of functionally mature sperm in vitro remains unachieved, converging progress in animal models and early human systems suggests that clinically revelant IVS and IVG applications are approaching feasibility, offering a paradigm shift in reproductive medicine. Full article

Background: Oral wound healing is a complex process influenced by extracellular matrix (ECM) remodeling and cellular migration. Hyaluronic acid (HA) and spermidine (SP) have shown regenerative potential, but their combined effects on oral tissues remain unexplored. This study aimed to characterize the effect of a gel composed of a mixture of HA and SP on the epithelial and connective compartments of oral tissue separately, evaluating (i) collagen turnover and cell migration on primary human gingival fibroblasts (HGFs) and (ii) epithelial integrity and cell proliferation on gingival organotypic cultures (OCs). Methods: HGFs were cultured, treated with HA-SP gel (1:0.5 HA-SP ratio) and evaluated for collagen types I and III (COL-I, COL-III), matrix metalloproteinase (MMP-1) protein and tissue inhibitor of MMP-1 (TIMP-1) levels secreted by the cells upon gel treatment, compared to CT. HGFs were also analyzed through a wound healing assay. Gingival samples were obtained to set OCs and were treated with different HA-SP formulations (HA 0.2%; 1:0.5 HA-SP ratio; 1:5 HA-SP ratio) to evaluate the beneficial addition of SP to HA for epithelial tissue. OC samples were formalin-fixed and paraffin-embedded and were stained with hematoxylin and eosin and immunostained for Ki-67 analysis. Results: In HGFs, the gel induced increased COL-III gene expression relative to that of COL-I after 48 h and stimulated cell migration, in turn favoring connective tissue remodeling and repair. In OCs, the gel preserved epithelial integrity up to 48 h, with the best effects observed with the 1:0.5 HA-SP ratio. After 72 h, epithelial detachment was more evident in HA formulations, suggesting that SP contributes to epithelial integrity. Conclusions: The HA-SP gel may support oral tissue healing by modulating ECM remodeling and maintaining epithelial integrity. The gel containing HA and SP at the 1:0.5 ratio may provide a promising solution for enhancing wound healing. Full article

Neural stem cells (NSCs) are crucial components of the nervous system, primarily located in the subventricular zone (SVZ) and subgranular zone (SGZ). The SVZ neural stem cell niche (NSCN) is a specialized microenvironment where growth factors and extracellular matrix (ECM) components collaborate to regulate NSC self-renewal and differentiation. Despite its importance, our understanding of the SVZ remains incomplete due to the inherent challenges of animal research, particularly given the tissue’s dynamic nature. To address these limitations, we developed a proof-of-concept, dynamic, and tissue-specific 3D organotypic SVZ model to reduce reliance on animal models. This static 3D organotypic model integrates a region-specific decellularized ECM derived from the SVZ, mimicking the native NSCN and supporting mouse-derived ependymal cells (ECs), radial glial cells (RGCs), astrocytes, and NSCs. To further improve physiological relevance, we incorporated a dynamic microfluidic culture system (SVZonChip), replicating cerebrospinal fluid (CSF) flow as observed in vivo. The resulting SVZonChip platform, combining region-specific ECM proteins with dynamic culture conditions, provides a sustainable and reproducible tool to minimize animal model use. It holds significant promise for studying SVZ-related diseases, such as congenital hydrocephalus, stroke, and post-stroke neurogenesis, while advancing translational research and enabling personalized medicine protocols. Full article

Background/Objectives: Metastatic prostate cancer (PCa) remains a major clinical challenge with limited therapeutic options. The long non-coding RNA H19 has been implicated in regulating cell adhesion molecules and collective migration, key features of metastatic dissemination. This study investigates the role of the Bromodomain and Extra-Terminal (BET) proteins BRD2, BRD3, and BRD4 in the H19-dependent transcriptional regulation of cell adhesion molecules. Currently, the major effects of BET inhibitors require androgen receptor (AR) expression. Methods: H19 was stably silenced in PC-3 (AR-null) and 22Rv1 (AR-positive) castration-resistant PCa cells. The cells were treated with the pan-BET inhibitors JQ1 and OTX015 or the BET degrader dBET6. In vivo, the effects of JQ1 were evaluated in xenograft mouse models. Chromatin immunoprecipitation (ChIP) and RNA-ChIP were used to assess BET protein recruitment and interaction with cell adhesion gene loci and H19. Organotypic slice cultures (OSCs) from fresh PCa surgical specimens were used as ex vivo models to validate transcriptional changes and BRD4 recruitment. Results: BET inhibition significantly reduced the expression of β4 integrin and E-cadherin and cell proliferation in both basal conditions, and following H19 knockdown in PC-3 and 22Rv1 cells. These effects were mirrored in JQ1-treated tumor xenografts, which showed marker downregulation and tumor regression. ChIP assays revealed that BRD4, more than BRD2/3, was enriched on β4 integrin and E-cadherin promoters, especially in regions marked by H3K27ac. H19 silencing markedly enhanced BRD4 promoter occupancy. RNA-ChIP confirmed a specific interaction between BRD4 and H19. These findings were validated in OSCs, reinforcing their clinical relevance. Conclusions: Our study demonstrates that BRD4 epigenetically regulates the H19-mediated transcriptional control of adhesion molecules involved in collective migration and metastatic dissemination. Importantly, these effects are independent of AR status, suggesting that targeting the H19/BRD4 axis may represent a promising therapeutic avenue for advanced PCa. Full article

Obesity is concurrent with immunological dysregulation, resulting in chronic low-grade inflammation and cellular dysfunction. In pancreatic islets, this loss of function has been correlated with mature β-cells dedifferentiating into a precursor-like state through constant exposure to inflammatory stressors. As mature adipocytes likewise have the capability to dedifferentiate in vitro and in vivo, we wanted to analyze this cellular change in relation to adipose tissue (AT) inflammation and adipose tissue macrophage (ATM) activity. Using our organotypic AT explant culture method combined with a double-reporter mouse model for labeling ATMs and mature adipocytes, we were able to visualize and quantify dedifferentiated fat (DFAT) cells in AT explants. Preliminary testing showed increased dedifferentiation after tamoxifen (TAM) stimulation, making TAM-dependent lineage-tracing models unsuitable for quantification of naturally occurring DFAT cells. The regulatory role of ATMs in adipocyte dedifferentiation was shown through macrophage depletion using Plexxicon 5622 or clodronate liposomes, which significantly increased DFAT cell levels. Subsequent bulk RNA sequencing of macrophage-depleted explants revealed enrichment of the tumor necrosis factor α (TNFα) signaling pathway as well as downregulation of associated genes. Direct stimulation with TNFα decreased adipocyte dedifferentiation, while application of a TNFα-neutralizing antibody did not significantly alter DFAT cell levels. Our findings suggest a regulatory role of resident ATMs in maintaining the mature adipocyte phenotype and preventing excessive adipocyte dedifferentiation. The specific regulatory pathways as well as the impact that DFAT cells might have on ATMs, and vice versa, are subject to further investigation. Full article

Tissue engineering research for neurological applications has demonstrated that biomaterial-based structural bridges present a promising approach for promoting regeneration. This is particularly relevant for penetrating traumatic brain injuries, where the clinical prognosis is typically poor, with no available regeneration-enhancing therapies. Specifically, repurposing clinically approved biomaterials offers many advantages (reduced approval time and achieving commercial scaleup for clinical applications), highlighting the need for detailed screening of potential neuromaterials. A major challenge in experimental testing is the limited availability of neuromimetic, technically accessible, cost-effective, and humane models of neurological injury for efficient biomaterial testing in injury-simulated environments. Three dimensional (3D) organotypic brain slices bridge the gap between live animal models and simplified co-cultures and are a versatile tool for studies on neural development, neurodegenerative disease and in drug testing. Despite this, their utility for investigation of neural cell responses to biomaterial implantation is poorly investigated. We demonstrate that murine brain organotypic slices can be used to develop a model of penetrating traumatic brain injury, wherein a surgical-grade biomaterial scaffold can be implanted into the lesion cavity. Critically, the model allowed for examination of key cellular responses involved in CNS injury pathology/biomaterial handling: astrogliosis, microglial activation and axonal sprouting. The approach offers a technically simple and versatile methodology to study biomaterial interventions as a regenerative therapy for neurological injuries. Full article

Three-dimensional organotypic models benefit from the ability to mimic physiological cell–cell or cell–matrix interactions and therefore offer superior models for studying pathological or physiological conditions compared to 2D cultures. Organotypic models consisting of keratinocytes supported by fibroblasts embedded in collagen matrices have been utilised for the study of oral conditions. However, the provision of a suitable model for investigating the pathogenesis of periodontitis has been more challenging. Part of the complexity relates to the different regional epithelial specificities and connective tissue phenotypes. Recently, it was confirmed, using 3D organotypic models, that distinct fibroblast populations were implicated in the provision of specific inductive and directive influences on the overlying epithelia. This paper presents the organotypic model of the dentogingival junction (DGJ) constructed to demonstrate the differential fibroblast influences on the maintenance of regionally specific epithelial phenotypes. Therefore, the review aims are (1) to provide the biological basis underlying 3D organotypic cultures and (2) to comprehensively detail the experimental protocol for the construction of the organotypic cultures and the unique setup for the DGJ model. The latter is the first organotypic culture model used for the reconstruction of the DGJ and is recommended as a useful tool for future periodontal research. Full article

Background/Objectives: Ibrutinib (IBR) is a tyrosine kinase inhibitor under investigation in preclinical and clinical settings as an alternative treatment for melanoma. Nevertheless, the limited oral bioavailability of IBR and the need for high doses of the drug to kill melanoma cells are major drawbacks for this purpose. Considering that melanoma is restricted to the skin at early stages, the topical application of IBR might constitute an effective and safer administration route. In this study, we determined IBR’s toxicity and dermatokinetics using human primary cells and human organotypic skin explant cultures (hOSECs). Methods: After demonstrating that human primary fibroblasts and keratinocytes present IBR target genes, the cytotoxicity of the drug was determined using the MTT and annexin V/PI staining assays. IBR toxicity in the skin was assessed using the TTC assay, and the irritation potential was established using histological assessment. Finally, IBR cutaneous permeation was assessed ex vivo to determine the drug dermatokinetics. Results: Our findings reveal that IBR exerts dose-dependent toxicity towards skin cells, presenting an IC₅₀ in the same range as melanoma cells. The topical application of the drug successfully reduced irritation and toxicity in the skin, and the drug was shown to successfully permeate the stratum corneum and reach the viable skin layers in therapeutic concentrations. Conclusions: Overall, our data encourage the topical application of IBR to treat melanoma, paving the way for future studies in this theme. Full article

A possible molecular mechanism of the ligand–receptor binding of Ac-Lys-Lys-Lys-NH₂ (Ac-KKK-NH₂) to the Na_V1.8 channel that is responsible for nociceptive signal coding in the peripheral nervous system is investigated by a number of experimental and theoretical techniques. Upon Ac-KKK-NH₂ application at 100 nM, a significant decrease in the effective charge carried by the Na_V1.8 channel activation gating system Z_eff is demonstrated in the patch-clamp experiments. A strong Ac-KKK-NH₂ analgesic effect at both the spinal and supraspinal levels is detected in vivo in the formalin test. The distances between the positively charged amino groups in the Ac-KKK-NH₂ molecule upon binding to the Na_V1.8 channel are 11–12 Å, as revealed by the conformational analysis. The blind docking with the Na_V1.8 channel has made it possible to locate the Ac-KKK-NH₂ binding site on the extracellular side of the voltage-sensing domain VSD_I. The Ac-KKK-NH₂ amino groups are shown to form ionic bonds with Asp151 and Glu157 and a hydrogen bond with Thr161, which affects the coordinated movement of the voltage sensor up and down, thus modulating the Z_eff value. According to the results presented, Ac-KKK-NH₂ is a promising candidate for the role of an analgesic medicinal substance that can be applied for pain relief in humans. Full article

Alzheimer’s disease (AD) is a neurodegenerative disease characterized by memory loss and progressive deterioration of cognitive functions. Being able to identify reliable biomarkers in easily available body fluids such as blood plasma is vital for the disease. To achieve this, we used a technique that applied human plasma to organotypic brain slice culture via microcontact printing. After a 2-week culture period, we performed immunolabeling for neurofilament and myelin oligodendrocyte glycoprotein (MOG) to visualize newly formed nerve fibers and oligodendrocytes. There was no significant change in the number of new nerve fibers in the AD plasma group compared to the healthy control group, while the length of the produced fibers significantly decreased. A significant increase in the number of MOG+ dots around these new fibers was detected in the patient group. According to our hypothesis, there are factors in the plasma of AD patients that affect the growth of new nerve fibers, which also affect the oligodendrocytes. Based on these findings, we selected the most promising plasma samples and conducted mass spectrometry using a differential approach and we identified three putative biomarkers: aldehyde-dehydrogenase 1A1, alpha-synuclein and protein S100-A4. Our method represents a novel and innovative approach for translating research findings from mouse models to human applications. Full article

Background/Objectives: Cancer organoids have emerged as a valuable tool of three-dimensional (3D) cell cultures to investigate tumor heterogeneity and predict tumor behavior and treatment response. We developed a 3D organotypic culture model of oral squamous cell carcinoma (OSCC) to recapitulate the tumor–stromal interface by co-culturing four cell types, including patient-derived cancer-associated fibroblasts (PD-CAFs). Methods: A stainless-steel ring was used twice to create the horizontal positioning of the cancer stroma (adjoining normal oral mucosa connective tissue) and the OSCC layer (surrounding normal oral mucosa epithelial layer). Combined with a structured bi-layered model of the epithelial component and the underlying stroma, this protocol enabled us to construct four distinct portions mimicking the oral cancer tissue arising in the oral mucosa. Results: In this model, α-smooth muscle actin-positive PD-CAFs were localized in close proximity to the OSCC layer, suggesting a crosstalk between them. Furthermore, a linear laminin-γ2 expression was lacking at the interface between the OSCC layer and the underlying stromal layer, indicating the loss of the basement membrane-like structure. Conclusions: Since the specific 3D architecture and polarity mimicking oral cancer in vivo provides a more accurate milieu of the tumor microenvironment (TME), it could be crucial in elucidating oral cancer TME. Full article

Genomic-oriented oncology has improved tumor classification, treatment options, and patient outcomes. However, genetic heterogeneity, tumor cell plasticity, and the ability of cancer cells to hijack the tumor microenvironment (TME) represent a major roadblock for cancer eradication. Recent biotechnological advances in organotypic cell cultures have revolutionized biomedical research, opening new avenues to explore the use of cancer organoids in functional precision oncology, especially when genomics alone is not a determinant. Here, we outline the potential and the limitations of tumor organoids in preclinical and translational studies with a particular focus on lung cancer pathogenesis, highlighting their relevance in predicting therapy response, evaluating treatment toxicity, and designing novel anticancer strategies. Furthermore, we describe innovative organotypic coculture systems to dissect the crosstalk with the TME and to test the efficacy of different immunotherapy approaches, including adoptive cell therapy. Finally, we discuss the potential clinical relevance of microfluidic mini-organ technology, capable of reproducing tumor vasculature and the dynamics of tumor initiation and progression, as well as immunomodulatory interactions among tumor organoids, cancer-associated fibroblasts (CAFs) and immune cells, paving the way for next-generation immune precision oncology. Full article

Alzheimer’s disease is a severe neurodegenerative disorder, and the discovery of biomarkers is crucial for early diagnosis. While the analysis of biomarkers in cerebrospinal fluid is well accepted, there are currently no blood biomarkers available. Our research focuses on identifying novel plasma biomarkers for Alzheimer’s disease. To achieve this, we employed a technique that involves coupling human plasma to mouse organotypic brain slices via microcontact prints. After culturing for two weeks, we assessed Iba1-immunopositive microglia on these microcontact prints. We hypothesized that plasma from Alzheimer’s patients contains factors that affect microglial migration. Our data indicated that plasma from Alzheimer’s patients significantly inhibited the migration of round Iba1-immunoreactive microglia (13 ± 3, n = 24, p = 0.01) compared to healthy controls (50 ± 16, n = 23). Based on these findings, we selected the most promising plasma samples and conducted mass spectrometry using a differential approach, and we identified four potential biomarkers: mannose-binding protein C, macrophage receptor MARCO, complement factor H-related protein-3, and C-reactive protein. Our method represents a novel and innovative approach to translate research findings from mouse models to human applications. Full article

HIV-associated neurocognitive disorders (HAND) persist under antiretroviral therapy as a complex pathology that has been difficult to study in cellular and animal models. Therefore, we generated an ex vivo human brain slice model of HIV-1 infection from surgically resected adult brain tissue. Brain slice cultures processed for flow cytometry showed >90% viability of dissociated cells within the first three weeks in vitro, with parallel detection of astrocyte, myeloid, and neuronal populations. Neurons within brain slices showed stable dendritic spine density and mature spine morphologies in the first weeks in culture, and they generated detectable activity in multi-electrode arrays. We infected cultured brain slices using patient-matched CD4+ T-cells or monocyte-derived macrophages (MDMs) that were exposed to a GFP-expressing R5-tropic HIV-1 in vitro. Infected slice cultures expressed viral RNA and developed a spreading infection up to 9 days post-infection, which were significantly decreased by antiretrovirals. We also detected infected myeloid cells and astrocytes within slices and observed minimal effect on cellular viability over time. Overall, this human-centered model offers a promising resource to study the cellular mechanisms contributing to HAND (including antiretroviral toxicity, substance use, and aging), infection of resident brain cells, and new neuroprotective therapeutics. Full article