Psychedelics reopen the social reward learning critical period.

Psychedelics are a broad class of drugs defined by their ability to induce an altered state of consciousness1,2. These drugs have been used for millennia in both spiritual and medicinal contexts, and a number of recent clinical successes have spurred a renewed interest in developing psychedelic therapies3-9. Nevertheless, a unifying mechanism that can account for these shared phenomenological and therapeutic properties remains unknown. Here we demonstrate in mice that the ability to reopen the social reward learning critical period is a shared property across psychedelic drugs. Notably, the time course of critical period reopening is proportional to the duration of acute subjective effects reported in humans. Furthermore, the ability to reinstate social reward learning in adulthood is paralleled by metaplastic restoration of oxytocin-mediated long-term depression in the nucleus accumbens. Finally, identification of differentially expressed genes in the 'open state' versus the 'closed state' provides evidence that reorganization of the extracellular matrix is a common downstream mechanism underlying psychedelic drug-mediated critical period reopening. Together these results have important implications for the implementation of psychedelics in clinical practice, as well as the design of novel compounds for the treatment of neuropsychiatric disease.

Advancing models of neural development with biomaterials.

Human pluripotent stem cells have emerged as a promising in vitro model system for studying the brain. Two-dimensional and three-dimensional cell culture paradigms have provided valuable insights into the pathogenesis of neuropsychiatric disorders, but they remain limited in their capacity to model certain features of human neural development. Specifically, current models do not efficiently incorporate extracellular matrix-derived biochemical and biophysical cues, facilitate multicellular spatio-temporal patterning, or achieve advanced functional maturation. Engineered biomaterials have the capacity to create increasingly biomimetic neural microenvironments, yet further refinement is needed before these approaches are widely implemented. This Review therefore highlights how continued progression and increased integration of engineered biomaterials may be well poised to address intractable challenges in recapitulating human neural development.

Breast cancer cells rely on environmental pyruvate to shape the metastatic niche.

The extracellular matrix is a major component of the local environment-that is, the niche-that determines cell behaviour1. During metastatic growth, cancer cells shape the extracellular matrix of the metastatic niche by hydroxylating collagen to promote their own metastatic growth2,3. However, only particular nutrients might support the ability of cancer cells to hydroxylate collagen, because nutrients dictate which enzymatic reactions are active in cancer cells4,5. Here we show that breast cancer cells rely on the nutrient pyruvate to drive collagen-based remodelling of the extracellular matrix in the lung metastatic niche. Specifically, we discovered that pyruvate uptake induces the production of α-ketoglutarate. This metabolite in turn activates collagen hydroxylation by increasing the activity of the enzyme collagen prolyl-4-hydroxylase (P4HA). Inhibition of pyruvate metabolism was sufficient to impair collagen hydroxylation and consequently the growth of breast-cancer-derived lung metastases in different mouse models. In summary, we provide a mechanistic understanding of the link between collagen remodelling and the nutrient environment in the metastatic niche.

Network modeling predicts personalized gene expression and drug responses in valve myofibroblasts cultured with patient sera.

Aortic valve stenosis (AVS) patients experience pathogenic valve leaflet stiffening due to excessive extracellular matrix (ECM) remodeling. Numerous microenvironmental cues influence pathogenic expression of ECM remodeling genes in tissue-resident valvular myofibroblasts, and the regulation of complex myofibroblast signaling networks depends on patient-specific extracellular factors. Here, we combined a manually curated myofibroblast signaling network with a data-driven transcription factor network to predict patient-specific myofibroblast gene expression signatures and drug responses. Using transcriptomic data from myofibroblasts cultured with AVS patient sera, we produced a large-scale, logic-gated differential equation model in which 11 biochemical and biomechanical signals were transduced via a network of 334 signaling and transcription reactions to accurately predict the expression of 27 fibrosis-related genes. Correlations were found between personalized model-predicted gene expression and AVS patient echocardiography data, suggesting links between fibrosis-related signaling and patient-specific AVS severity. Further, global network perturbation analyses revealed signaling molecules with the most influence over network-wide activity, including endothelin 1 (ET1), interleukin 6 (IL6), and transforming growth factor ß (TGFß), along with downstream mediators c-Jun N-terminal kinase (JNK), signal transducer and activator of transcription (STAT), and reactive oxygen species (ROS). Lastly, we performed virtual drug screening to identify patient-specific drug responses, which were experimentally validated via fibrotic gene expression measurements in valvular interstitial cells cultured with AVS patient sera and treated with or without bosentan-a clinically approved ET1 receptor inhibitor. In sum, our work advances the ability of computational approaches to provide a mechanistic basis for clinical decisions including patient stratification and personalized drug screening.

Lysosome dynamics during human endometrial stromal cells decidualization: effect of para-nonylphenol.

During the process of decidualization, the stromal cells of the endometrium change dynamically to create a favorable environment for embryo implantation. Lysosome activity has often been associated with physiological changes in the endometrium during the preimplantation period and early pregnancy. In this study, the effect of para-nonylphenol (p-NP), an endocrine disruptor, on human immortalized endometrial stromal cells (tHESCs) was investigated. After exposure to p-NP (1 nM and 1 pM), the cells were examined for the decidualization markers connexin-43, insulin like growth factor binding protein 1 (IGFBP1), and prolactin. In addition, the effect of p-NP on lysosome biogenesis and exocytosis was investigated by examining the expression and localization of the transcription factor EB (TFEB) and that of the lysosomal-associated membrane protein 1 (LAMP-1). Finally, we evaluated the effect of p-NP on extracellular matrix (ECM) remodeling using a fibronectin assay. Our results showed that p-NP reduced the expression of prolactin protein, increased the nuclear localization of TFEB, and induced the increase and translocation of the lysosomal protein LAMP-1 to the membrane of tHESCs. The data indicate an impairment of decidualization and suggest an increase in lysosomal biogenesis and exocytosis, which is supported by the higher release of active cathepsin D by tHESCs. Given the importance of cathepsins in the processing and degradation of the ECM during trophoblast invasiveness and migration into the decidua, our results appear to be clear evidence of the negative effects of p-NP on endometrial processes that are fundamental to reproductive success and the establishment of pregnancy.NEW & NOTEWORTHY Endocrine disruptors, such as para-nonylphenol, affect the decidualization of human endometrial stromal cells with an impact on decidualization itself, lysosome biogenesis and exocytosis, and extracellular matrix remodeling. All these alterations may negatively impact embryo implantation with the success of reproduction and the establishment of pregnancy.

Intratumor transforming growth factor-ß signaling with extracellular matrix-related gene regulation marks chemotherapy-resistant gastric cancer.

Drug-tolerant persister (DTP) cells remain following chemotherapy and can cause cancer relapse. However, it is unclear when acquired resistance to chemotherapy emerges. Here, we compared the gene expression profiles of gastric cancer patient-derived cells (GC PDCs) and their respective xenograft tumors with different sensitivities to 5-fluorouracil (5-FU) by using immunodeficient female BALB/c-nu mice. RNA sequencing analysis of 5-FU-treated PDCs demonstrated that DNA replication/cell cycle-related genes were transiently induced in the earlier phase of DTP cell emergence, while extracellular matrix (ECM)-related genes were sustainably upregulated during long-term cell survival in 5-FU-resistant residual tumors. NicheNet analysis, which uncovers cell-cell signal interactions, indicated the transforming growth factor-ß (TGF-ß) pathway as the upstream regulator in response to 5-FU treatment. This induced ECM-related gene expression in the 5-FU-resistant tumor model. In the 5-FU-resistant residual tumors, there was a marked upregulation of cancer cell-derived TGF-ß1 expression and increased phosphorylation of SMAD3, a downstream regulator of the TGF-ß receptor. By contrast, these responses were not observed in a 5-FU-sensitive tumor model. We further found that TGF-ß-related upregulation of ECM genes was preferentially observed in non-responders to chemotherapy with 5-FU and/or oxaliplatin among 22 patient-derived xenograft tumors. These observations suggest that chemotherapy-induced activation of the TGF-ß1/SMAD3/ECM-related gene axis is a potential biomarker for the emergence of drug resistance in GCs.

Laminin I mediates resistance to lapatinib in HER2-positive brain metastatic breast cancer cells in vitro.

The role of extracellular matrix (ECM) prevalent in the brain metastatic breast cancer (BMBC) niche in mediating cancer cell growth, survival, and response to therapeutic agents is not well understood. Emerging evidence suggests a vital role of ECM of the primary breast tumor microenvironment (TME) in tumor progression and survival. Possibly, the BMBC cells are also similarly influenced by the ECM of the metastatic niche; therefore, understanding the effect of the metastatic ECM on BMBC cells is imperative. Herein, we assessed the impact of various ECM components (i.e., Tenascin C, Laminin I, Collagen I, Collagen IV, and Fibronectin) on brain metastatic human epidermal growth factor receptor 2 (HER2)-positive and triple negative breast cancer (TNBC) cell lines in vitro. The highly aggressive TNBC cell line was minimally affected by ECM components exhibiting no remarkable changes in viability and morphology. On the contrary, amongst various ECM components tested, the HER2-positive cell line was significantly affected by Laminin I with higher viability and demonstrated a distinct spread morphology. In addition, HER2-positive BMBC cells exhibited resistance to Lapatinib in presence of Laminin I. Mechanistically, Laminin I-induced resistance to Lapatinib was mediated in part by phosphorylation of Erk 1/2 and elevated levels of Vimentin. Laminin I also significantly enhanced the migratory potential and replicative viability of HER2-positive BMBC cells. In sum, our findings show that presence of Laminin I in the TME of BMBC cells imparts resistance to targeted therapeutic agent Lapatinib, while increasing the possibility of its dispersal and clonogenic survival.

ECM-mimetic, NSAIDs loaded thermo-responsive, immunomodulatory hydrogel for rheumatoid arthritis treatment.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease, and it leads to irreversible inflammation in intra-articular joints. Current treatment approaches for RA include non-steroidal anti-inflammatory drugs (NSAIDs), disease-modifying anti-rheumatic drugs (DMARDs), corticosteroids, and biological agents. To overcome the drug-associated toxicity of conventional therapy and transdermal tissue barrier, an injectable NSAID-loaded hydrogel system was developed and explored its efficacy. RESULTS: The surface morphology and porosity of the hydrogels indicate that they mimic the natural ECM, which is greatly beneficial for tissue healing. Further, NSAIDs, i.e., diclofenac sodium, were loaded into the hydrogel, and the in vitro drug release pattern was found to be burst release for 24 h and subsequently sustainable release of 50% drug up to 10 days. The DPPH assay revealed that the hydrogels have good radical scavenging activity. The biocompatibility study carried out by MTT assay proved good biocompatibility and anti-inflammatory activity of the hydrogels was carried out by gene expression study in RAW 264.7 cells, which indicate the downregulation of several key inflammatory genes such as COX-2, TNF-α & 18s. CONCLUSION: In summary, the proposed ECM-mimetic, thermo-sensitive in situ hydrogels may be utilized for intra-articular inflammation modulation and can be beneficial by reducing the frequency of medication and providing optimum lubrication at intra-articular joints.

Serum deprivation protein response intervenes in the proliferation, motility, and extracellular matrix production in keloid fibroblasts by blocking the amplification of TGF-ß1/SMAD signal cascade via ERK1/2.

Keloid formation has been linked to abnormal fibroblast function, such as excessive proliferation and extracellular matrix (ECM) production. Serum deprivation protein response (SDPR) is a crucial regulator of cellular function under diverse pathological conditions, yet its role in keloid formation remains unknown. The current work investigated the function of SDPR in regulating the proliferation, motility, and ECM production of keloid fibroblasts (KFs), as well as to decipher the mechanisms involved. Analysis of RNA sequencing data from the GEO database demonstrated significant down-regulation of SDPR in KF compared to normal fibroblasts (NFs). This down-regulation was also observed in clinical keloid specimens and isolated KFs. Overexpression of SDPR suppressed the proliferation, motility, and ECM production of KFs, while depletion of SDPR exacerbated the enhancing impact of TGF-ß1 on the proliferation, motility, and ECM production of NFs. Mechanistic studies revealed that SDPR overexpression repressed TGF-ß/Smad signal cascade activation in KFs along with decreased levels of phosphorylated Samd2/3, while SDPR depletion exacerbated TGF-ß/Smad activation in TGF-ß1-stimulated NFs. SDPR overexpression also repressed ERK1/2 activation in KFs, while SDPR depletion exacerbated ERK1/2 activation in TGF-ß1-stimulated NFs. Inhibition of ERK1/2 abolished SDPR-depletion-induced TGF-ß1/Smad activation, cell proliferation, motility, and ECM production in NFs. In conclusion, SDPR represses the proliferation, motility, and ECM production in KFs by blocking the TGF-ß1/Smad pathway in an ERK1/2-dependent manner. The findings highlight the role of SDPR in regulating abnormal behaviors of fibroblasts associated with keloid formation and suggest it as a potential target for anti-keloid therapy development.

Hydrogels to Recapture Extracellular Matrix Cues That Regulate Vascularization.

The ECM (extracellular matrix) is a 3-dimensional network that supports cellular responses and maintains structural tissue integrity in healthy and pathological conditions. The interactions between ECM and cells trigger signaling cascades that lead to phenotypic changes and structural and compositional turnover of the ECM, which in turn regulates vascular cell behavior. Hydrogel biomaterials are a powerful platform for basic and translational studies and clinical applications due to their high swelling capacity and exceptional versatility in compositions and properties. This review highlights recent developments and uses of engineered natural hydrogel platforms that mimic the ECM and present defined biochemical and mechanical cues for vascularization. Specifically, we focus on modulating vascular cell stimulation and cell-ECM/cell-cell interactions in the microvasculature that are the established biomimetic microenvironment.

17ß-estradiol activates SOX6 to balance the anabolism and catabolism via estrogen receptor 2 in chondrocyte.

We investigated the influence of 17ß-estradiol (17ß-E2) on cartilage extracellular matrix (ECM) homeostasis in postmenopausal women. We focused on the roles of estrogen receptors (ESR) and SOX6 in 17ß-E2-mediated stimulation of ECM metabolism during chondrocyte (CH) degeneration. We compared the expression of anabolic genes (collagen II and aggrecan) and catabolic genes (MMPs and TIMPs) in IL-1ß-induced CH degeneration in vitro, with and without 17ß-E2 supplementation. We separately silenced the SOX6, ESR1, and ESR2 genes in CHs to determine their impact on 17ß-E2 treatment. Additionally, we used Chromatin immunoprecipitation followed by DNA sequencing (ChIP-seq) and luciferase assays to investigate protein-DNA interactions within ESR2 and SOX6-promoter complexes. After three days of IL-1ß treatment, ESR1/2, SOX6, collagen II, aggrecan, and TIMP1/3 were decreased, while MMP3/9/13 were increased. The addition of 17ß-E2 partially reversed these effects, but silencing SOX6, ESR1, or ESR2 weakened the protective effects of 17ß-E2. Silencing ESR2, but not ESR1, abolished the upregulation of SOX6 induced by 17ß-E2. ESR2 was found to bind the SOX6 promoter and regulate SOX6 expression. 17ß-E2 upregulates SOX6 through ESR2 mediation, and the synergistic effect of 17ß-E2 and ESR2 on SOX6 balances ECM metabolism in CHs.

Tubastatin alleviates epidural fibrosis via negatively targeting TGFß/PI3K/Akt pathway.

Epidural fibrosis (EF) is a chronic, progressive and severe disease. Histone deacetylase 6 (HDAC6) regulates biological signals and cell activities by deacetylating lysine residues and participates in TGF-ß-induced epithelial-mesenchymal transition (EMT). Nevertheless, the effect and mechanism of HDAC6 in EF remain unclear. To investigate the effect and mechanism of HDAC6 inhibition on repressing epidural fibrosis. HDAC6 expression and α-smooth muscle actin (α-SMA) in normal human tissue and human EF tissue were assessed by quantitative real-time PCR (qRT-PCR) and western blotting. Human fibroblasts were treated with TGF-ß ± HDAC6 inhibitors (Tubastatin) and fibrotic markers including collagen I, collagen III, α-SMA and fibronectin were assessed using western blotting. Then TGFß1 receptor (TGFß1-R), PI3K and Akt were analyzed using qRT-PCR and western blotting. Rats were undergone laminectomy± Tubastatin (intraperitoneally injection; daily for 7 days) and epidural scar extracellular matrix (ECM) expression was gauged using immunoblots. Increasing HDAC6 expression was associated with α-SMA enrichment. Tubastatin remarkably restrained TGF-ß-induced level of collagen and ECM deposition in human fibroblasts, and the discovery was accompanied by decreased PI3K and Akt phosphorylation. Moreover, Tubastatin also inhibited TGF-ß-mediated HIF-1α and VEGF expression. In the epidural fibrosis model, we found that Tubastatin weakened scar hyperplasia and collagen deposition, and effectively inhibited the process of epidural fibrosis. These results indicated that Tubastatin inhibited HDAC6 expression and decreased TGF-ß/ PI3K/ Akt pathway that promotes collagen and ECM deposition and VEGF release, leading reduction of myofibroblast activation. Hence, Tubastatin ameliorated epidural fibrosis development.

Maslinic acid alleviates intervertebral disc degeneration by inhibiting the PI3K/AKT and NF-κB signaling pathways.

Intervertebral disc degeneration (IDD) is the cause of low back pain (LBP), and recent research has suggested that inflammatory cytokines play a significant role in this process. Maslinic acid (MA), a natural compound found in olive plants ( Olea europaea), has anti-inflammatory properties, but its potential for treating IDD is unclear. The current study aims to investigate the effects of MA on TNFα-induced IDD in vitro and in other in vivo models. Our findings suggest that MA ameliorates the imbalance of the extracellular matrix (ECM) and mitigates senescence by upregulating aggrecan and collagen II levels as well as downregulating MMP and ADAMTS levels in nucleus pulposus cells (NPCs). It can also impede the progression of IDD in rats. We further find that MA significantly affects the PI3K/AKT and NF-κB pathways in TNFα-induced NPCs determined by RNA-seq and experimental verification, while the AKT agonist Sc-79 eliminates these signaling cascades. Furthermore, molecular docking simulation shows that MA directly binds to PI3K. Dysfunction of the PI3K/AKT pathway and ECM metabolism has also been confirmed in clinical specimens of degenerated nucleus pulposus. This study demonstrates that MA may hold promise as a therapeutic agent for alleviating ECM metabolism disorders and senescence to treat IDD.

Juvenile hormone signaling promotes ovulation and maintains egg shape by inducing expression of extracellular matrix genes.

It is well documented that the juvenile hormone (JH) can function as a gonadotropic hormone that stimulates vitellogenesis by activating the production and uptake of vitellogenin in insects. Here, we describe a phenotype associated with mutations in the Drosophila JH receptor genes, Met and Gce: the accumulation of mature eggs with reduced egg length in the ovary. JH signaling is mainly activated in ovarian muscle cells and induces laminin gene expression in these cells. Meanwhile, JH signaling induces collagen IV gene expression in the adult fat body, from which collagen IV is secreted and deposited onto the ovarian muscles. Laminin locally and collagen IV remotely contribute to the assembly of ovarian muscle extracellular matrix (ECM); moreover, the ECM components are indispensable for ovarian muscle contraction. Furthermore, ovarian muscle contraction externally generates a mechanical force to promote ovulation and maintain egg shape. This work reveals an important mechanism for JH-regulated insect reproduction.

Vitamin B6 alleviates osteoarthritis by suppressing inflammation and apoptosis.

BACKGROUND: Although various anti-inflammatory medicines are widely recommended for osteoarthritis (OA) treatment, no significantly clinical effect has been observed. This study aims to examine the effects of vitamin B6, a component that has been reported to be capable of alleviating inflammation and cell death in various diseases, on cartilage degeneration in OA. METHODS: Collagen-induced arthritis (CIA) mice model were established and the severity of OA in cartilage was determined using the Osteoarthritis Research Society International (OARSI) scoring system. The mRNA and protein levels of indicators associated with extracellular matrix (ECM) metabolism, apoptosis and inflammation were detected. The effect of vitamin B6 (VB6) on the mice were assessed using HE staining and masson staining. The apoptosis rate of cells was assessed using TdT-mediated dUTP nick end labeling. RESULTS: Our results showed a trend of improved OARSI score in mice treated with VB6, which remarkably inhibited the hyaline cartilage thickness, chondrocyte disordering, and knees hypertrophy. Moreover, the VB6 supplementation reduced the protein expression of pro-apoptosis indicators, including Bax and cleaved caspase-3 and raised the expression level of anti-apoptosis marker Bcl-2. Importantly, VB6 improved ECM metabolism in both in vivo and in vitro experiments. CONCLUSIONS: This study demonstrated that VB6 alleviates OA through regulating ECM metabolism, inflammation and apoptosis in chondrocytes and CIA mice. The findings in this study provide a theoretical basis for targeted therapy of OA, and further lay the theoretical foundation for studies of mechanisms of VB6 in treating OA.

Aflatoxin B1 inhibited the development of primary myoblasts of grass carp (Ctenopharyngodon idella) by degrading extracellular matrix.

According to the International Agency for Research on Cancer (IARC), aflatoxin B1 (AFB1) has been recognized as a major contaminant in food and animal feed and which is a common mycotoxin with high toxicity. Previous research has found that AFB1 inhibited zebrafish muscle development. However, the potential mechanism of AFB1 on fish muscle development is unknown, so it is necessary to conduct further investigation. In the present research, the primary myoblast of grass carp was used as a model, we treated myoblasts with AFB1 for 24 h. Our results found that 5 µM AFB1 significantly inhibited cell proliferation and migration (P < 0.05), and 10 µM AFB1 promoted lactate dehydrogenase (LDH) release (P < 0.05). Reactive oxygen species (ROS), protein carbonyl (PC) and malondialdehyde (MDA) levels were increased in 15, 5 and 10 µM AFB1 (P < 0.05), respectively. Catalase (CAT), glutathione peroxidase (GPx) and total superoxide dismutase (T-SOD) activities were decreased in 10, 10 and 15 µM AFB1 (P < 0.05), respectively. Furthermore, 15 µM AFB1 induced oxidative damage by Nrf2 pathway, also induced apoptosis in primary myoblast of grass carp. Meanwhile, 15 µM AFB1 decreased MyoD gene and protein expression (P < 0.05). Importantly, 15 µM AFB1 decreased the protein expression of collagen Ⅰ and fibronectin (P < 0.05), and increased the protein levels of urokinase plasminogen activator (uPA), matrix metalloproteinase 9 (MMP-9), matrix metalloproteinase 2 (MMP-2), and p38 mitogen-activated protein kinase (p38MAPK) (P < 0.05). As a result, our findings suggested that AFB1 damaged the cell morphology, induced oxidative damage and apoptosis, degraded ECM components, in turn inhibiting myoblast development by activating the p38MAPK/urokinase-type plasminogen activator (uPA)/matrix metalloproteinase (MMPs)/extracellular matrix (ECM) signaling pathway.

Deoxynivalenol triggers mitotic catastrophe and apoptosis in C2C12 myoblasts.

Deoxynivalenol (DON), commonly known as vomitoxin, is a mycotoxin produced by fungi and is frequently found as a contaminant in various cereal-based food worldwide. While the harmful effects of DON have been extensively studied in different tissues, its specific impact on the proliferation of skeletal muscle cells remains unclear. In this study, we utilized murine C2C12 myoblasts as a model to explore the influence of DON on their proliferation. Our observations indicated that DON exhibits dose-dependent toxicity, significantly inhibiting the proliferation of C2C12 cells. Through the application of RNA-seq analysis combined with gene set enrichment analysis, we identified a noteworthy downregulation of genes linked to the extracellular matrix (ECM) and condensed chromosome. Concurrently with the reduced expression of ECM genes, immunostaining analysis revealed notable changes in the distribution of fibronectin, a vital ECM component, condensing into clusters and punctate formations. Remarkably, the exposure to DON induced the formation of multipolar spindles, leading to the disruption of the normal cell cycle. This, in turn, activated the p53-p21 signaling pathway and ultimately resulted in apoptosis. These findings contribute significant insights into the mechanisms through which DON induces toxicity within skeletal muscle cells.

Scutellarein alleviates osteoarthritis progression through the PI3K/Akt/NF-kappaB signaling pathway: In vitro and in vivo studies.

Osteoarthritis (OA), a joint disease that is associated with inflammatory processes is involved in joint destruction. Scutellarein (Scu), a component of the medicinal herbs Scutellaria barbata D. Don and Erigeron breviscapus (vant) Hand Mass, has anti-inflammatory effects. We explored the role of Scu in the development of OA and the underlying mechanisms. CCK-8 assays, Calcein-AM/PI and EdU staining were used to determine chondrocyte viability after Scu exposure. Western blot, qPCR, as well as ELISA were utilized to measure extracellular matrix (ECM) degradation and inflammation. Immunofluorescence (IF), western blot and luciferase assays were used to examine the NF-kappaB (NF-κB) pathway. Scu interacting proteins were predicted using network pharmacology analysis and molecular docking. X-ray, H&E, Safranin O-Fast Green(S-O), toluidine blue, and immunohistochemistry analysis were used to examine the therapeutic effects of Scu in OA using destabilization of medial meniscus (DMM) models. Scu demonstrated inhibitory effects on ECM degradation and pro-inflammatory factor levels in chondrocytes treated with IL-1ß. Mechanistically, Scu inhibited the IL-1ß-induced activation of the PI3K/Akt/ NF-κB signaling pathway cascades. Furthermore, Scu has been shown to have significant binding capacities to PI3K. Additionally, Scu ameliorated the OA progression in DMM models. Our findings suggest that Scu may contribute to the amelioration of OA progression by targeting the PI3K/Akt/NF-κB signaling pathway, implying Scu possesses promising therapeutic potential for the treatment of OA.

Ethyl Pyruvate Decreases Collagen Synthesis and Upregulates MMP Activity in Keloid Fibroblasts and Keloid Spheroids.

Keloids, marked by abnormal cellular proliferation and excessive extracellular matrix (ECM) accumulation, pose significant therapeutic challenges. Ethyl pyruvate (EP), an inhibitor of the high-mobility group box 1 (HMGB1) and TGF-ß1 pathways, has emerged as a potential anti-fibrotic agent. Our research evaluated EP's effects on keloid fibroblast (KF) proliferation and ECM production, employing both in vitro cell cultures and ex vivo patient-derived keloid spheroids. We also analyzed the expression levels of ECM components in keloid tissue spheroids treated with EP through immunohistochemistry. Findings revealed that EP treatment impedes the nuclear translocation of HMGB1 and diminishes KF proliferation. Additionally, EP significantly lowered mRNA and protein levels of collagen I and III by attenuating TGF-ß1 and pSmad2/3 complex expression in both human dermal fibroblasts and KFs. Moreover, metalloproteinase I (MMP-1) and MMP-3 mRNA levels saw a notable increase following EP administration. In keloid spheroids, EP induced a dose-dependent reduction in ECM component expression. Immunohistochemical and western blot analyses confirmed significant declines in collagen I, collagen III, fibronectin, elastin, TGF-ß, AKT, and ERK 1/2 expression levels. These outcomes underscore EP's antifibrotic potential, suggesting its viability as a therapeutic approach for keloids.

Cryo-storage of porcine hides at the industrial scale for tissue engineering and regenerative medicine application.

BACKGROUND: The industrial scale cryo-storage of raw tissue materials requires a robust, low-cost and easy-to-operate method that can facilitate the down-stream process. OBJECTIVE: The study was aimed to develop the multifunctional protective solutions (MPS) for transportation at ambient conditions and also subsequent cryo-storage below -20 degree C of raw porcine hides for tissue engineering and regenerative medicine. MATERIALS AND METHODS: Protective solutions with antimicrobial activity and proteinase-inhibiting activity were developed and tested for its efficacy in preserving the extracellular matrix of porcine dermis from microbial spoilage, proteolytic degradation, freeze damage and excessive dehydration during shipping and cryo-storage. The MPSs contained phosphate-buffered saline with ethylene diamine tetra acetic acid (EDTA) added as chelator and proteinase inhibitor, as well as glycerol or maltodextrin (M180) as cryoprotectants. RESULTS: MPSs prepared with EDTA and glycerol or M180 had significant antimicrobial activity and proteinase-inhibiting activity during the period of shipping and handling. Glycerol and M180 prevented eutectic salt precipitation and excessive freeze dehydration upon cryo-storage of porcine hides. Without glycerol or M180, hides could be freeze-dehydrated to the low hydration at ~0.4 g/g dw, and formed irreversible plications after freezing. A critical hydration (0.8~0.9 g/g dw) was observed for the extracellular matrix of porcine dermis, and dehydration to a lower level could impose enormous stress and potential damage. The soaking of porcine hides in MPSs decreased water content as glycerol and M180 entered into dermis. Upon equilibration, the glycerol content in the tissue was about 94% of the incubating glycerol solution, but the M180 content in the tissue was only about 50% of the incubating M180 solution, indicating that M180 did not get into the entire aqueous domain within dermis. MPSs reduced ice formation and increased the unfrozen water content of porcine raw hides upon cryo-storage. CONCLUSION: MPSs prepared with EDTA and glycerol or M180 have antimicrobial activity and proteinase-inhibiting activity, which can be used for transportation and cryo-storage of raw hides at the industrial scale. Glycerol at 7.5% w/v and M180 at 20% w/v were sufficient to prevent freeze damage and excessive freeze dehydration. Doi.org/10.54680/fr24310110312.