Human amniotic mesenchymal stem cells-derived IGFBP-3, DKK-3, and DKK-1 attenuate liver fibrosis through inhibiting hepatic stellate cell activation by blocking Wnt/β-catenin signaling pathway in mice

Regulation of Fuzheng Huayu capsule on inhibiting the fibrosis-associated hepatocellular carcinogenesis

In the current study, bioinformatics analysis of the hepatocellular carcinoma (HCC) dataset was conducted with the hepatoprotective effect of the Fuzheng Huayu (FZHY) capsule against the diethylnitrosamine-induced HCC progression analyzed. Eight cell clusters were defined and tanshinone IIA, arachidonic acid, and quercetin, compounds of the FZHY capsule, inhibit HCC progression-related fibrosis by regulating the expression of PLAU and IGFBP3. Combined with the ameliorative effect of the FZHY capsule against liver dysfunctions and expression of PLAU and IGFBP3, our study confirmed the effect of the FZHY capsule on inhibiting the fibrosis-associated HCC progression via regulating the expression of PLAU and IGFBP3.

Associations of serum Dickkopf-1 levels with disease severity and 90-day Prognosis after spontaneous intracerebral hemorrhage: results from the prospective cohort study

Dickkopf-1 (DKK-1) may be involved in inflammatory response and secondary brain injury after acute brain injury. We gauged serum DKK-1 levels and further assessed its correlation with disease severity and investigated its predictive value for 90-day prognosis in patients with spontaneous intracerebral hemorrhage (sICH). Serum DKK-1 levels were measured in 128 sICH patients and 128 healthy controls. The severity of sICH was assessed using the Glasgow Coma Scale (GCS) scores and hematoma volumes. Poor prognosis was referred to as a Glasgow Outcome Scale (GOS) score of 1-3 at 90 days after stroke. Multivariate analysis was performed to identify associations of serum DKK-1 levels with disease severity, early neurological deterioration (END) and poor prognosis. Receiver operating characteristic curve (ROC) was built to investigate the prognostic predictive capability. The serum DKK-1 levels of patients were significantly higher than those of controls (median, 4.74 ng/mL versus 1.98 ng/mL; P < 0.001), and were independently correlated with hematoma volumes (ρ = 0.567, P < 0.001; t = 3.444, P = 0.001) and GCS score (ρ = -0.612, P < 0.001; t = -2.048, P = 0.043). Serum DKK-1 significantly differentiated patients at risk of END (area under ROC curve (AUC), 0.850; 95% confidence interval (CI), 0.777-0.907; P < 0.001) and poor prognosis (AUC, 0.830; 95% CI, 0.753-0.890; P < 0.001), which had similar prognostic ability, as compared to GCS scores and hematoma volumes. Subsequent Logistic regression model affirmed that GCS score, hematoma volume, and serum DKK-1 levels were independently associated with END and poor prognosis at 90 days after sICH. The models, which contained them, performed well using ROC curve analysis and calibration curve analysis. Serum DKK-1 levels are markedly associated with disease severity, END and 90-day poor prognosis in sICH. Hence, serum DKK-1 is presumed to be used as a potential prognostic biomarker of sICH.

Human amniotic mesenchymal stem cell-islet organoids enhance the efficiency of islet engraftment in a mouse diabetes model

AIMS

Despite islet transplantation has proved a great potential to become the standard therapy for type 1 diabetes mellitus (T1DM), this approach remains limited by ischemia, hypoxia, and poor revascularization in early post-transplant period as well as inflammation and life-long host immune rejection. Here, we investigate the potential and mechanism of human amniotic mesenchymal stem cells (hAMSCs)-islet organoid to improve the efficiency of islet engraftment in immunocompetent T1DM mice.

MAIN METHODS

We generated the hAMSC-islet organoid structure through culturing the mixture of hAMSCs and islets on 3-dimensional-agarose microwells. Flow cytometry, whole-body fluorescent imaging, immunofluorescence, Calcein-AM/PI staining, ELISA, and qPCR were used to assess the potential and mechanism of shielding hAMSCs to improve the efficiency of islet transplantation.

KEY FINDINGS

Transplant of hAMSC-islet organoids results in remarkably better glycemic control, an enhanced glucose tolerance, and a higher β cell mass in vivo compared with control islets. Our results show that hAMSCs shielding provides an immune privileged microenvironment for islets and promotes graft revascularization in vivo. In addition, hAMSC-islet organoids show higher viability and reduced dysfunction after exposure to hypoxia and inflammatory cytokines in vitro. Finally, our results show that shielding with hAMSCs leads to the activation of PKA-CREB-IRS2-PI3K and PKA-PDX1 signaling pathways, up-regulation of SIL1 mRNA levels, and down-regulation of MT1 mRNA levels in β cells, which ultimately promotes the synthesis, folding and secretion of insulin, respectively.

SIGNIFICANCE

hAMSC-islet organoids can evidently increase the efficiency of islet engraftment and might develop into a promising alternative for the clinical treatment of T1DM.

The role and mechanism of β-catenin-mediated skeletal muscle satellite cells in osteoporotic fractures by Jian-Pi-Bu-Shen formula

Osteoporosis is a metabolic bone disease. β-Catenin is associated with fractures. Jian-Pi-Bu-Shen (JPBS) can promote the healing of osteoporotic fractures (OPF). However, the mechanism of β-catenin-mediated skeletal muscle satellite cells (SMSCs) in OPF by the JPBS is unclear. SMSCs were isolated and divided into five groups. The results showed that the survival rate of SMSCs was significantly higher in the low, medium, and high dose JPBS-containing serum groups after 7 days of incubation. The ALP activity and the number of SMSCs mineralized in the JPBS-containing serum intervention group were elevated. Axin, GSK-3β, β-catenin siRNAs were constructed and transfected into cells. Transfection of siRNAs reduced Axin, GSK-3β, and β-catenin expressions, respectively. β-Catenin-siRNA reversed ALP activity, the number of SMSCs mineralized, and the expression of β-catenin, BMP2, Runx2, COL-I, SP7/Ostrix, Osteocalcin, and BMP-7. Transcriptomic results suggested that the TNF signaling pathway associated with OPF was enriched. SD rats were subjected to the construction of OPF model by removing the ovaries. JPBS decreased the levels of PINP, ALP, CTX, and NTX through β-catenin in OPF rats, while increasing Runx2, β-catenin expressions through β-catenin at the broken end of fractures. Moreover, JPBS decreased BMC, BMD, and BV/TV and improved pathological damage through β-catenin in OPF rats. JPBS decreased the expression of Axin, GSK-3β mRNA, and protein, but increased the expressions of β-catenin, Pax7, COL-II, COL-II, BMP2, and Runx2 through β-catenin in OPF rats. In conclusion, JPBS inhibits Axin/GSK-3β expression, activates the β-catenin signaling, and promotes the osteogenic differentiation of SMSCs.

Recent Advances in Hydrogel Technology in Delivering Mesenchymal Stem Cell for Osteoarthritis Therapy

Osteoarthritis (OA), a chronic joint disease affecting over 500 million individuals globally, is characterized by the destruction of articular cartilage and joint inflammation. Conventional treatments are insufficient for repairing damaged joint tissue, necessitating novel therapeutic approaches. Mesenchymal stem cells (MSCs), with their potential for differentiation and self-renewal, hold great promise as a treatment for OA. However, challenges such as MSC viability and apoptosis in the ischemic joint environment hinder their therapeutic effectiveness. Hydrogels with biocompatibility and degradability offer a three-dimensional scaffold that support cell viability and differentiation, making them ideal for MSC delivery in OA treatment. This review discusses the pathological features of OA, the properties of MSCs, the challenges associated with MSC therapy, and methods for hydrogel preparation and functionalization. Furthermore, it highlights the advantages of hydrogel-based MSC delivery systems while providing insights into future research directions and the clinical potential of this approach.

Adipose-derived mesenchymal stromal cells alleviate intestinal fibrosis: The role of tumor necrosis factor-stimulated gene 6 protein

BACKGROUND

The therapeutic potential of adipose-derived mesenchymal stromal cells (AMSCs) in the treatment of intestinal fibrosis occured in patients with Crohn's disease (CD) remains unclear. Tumor necrosis factor-stimulated gene 6 (TSG6) protein plays a critical role in inflammation regulation and tissue repair. This study aimed to determine if AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein and explore the underlying mechanisms.

METHODS

Two murine models for intestinal fibrosis were established using 2,4,6-trinitrobenzene sulfonic acid in BALB/c mice and dextran sulfate sodium in C57BL/6 mice. Primary human fibroblasts and CCD-18co cells were incubated with transforming growth factor (TGF)-β1 to build two fibrosis cell models in vitro.

RESULTS

Intraperitoneally administered AMSCs attenuated intestinal fibrosis in the two murine models, as evidenced by significant alleviation of colon shortening, collagen protein deposits, and submucosal thickening, and also decrease in the endoscopic and fibrosis scores (P < 0.001). Although intraperitoneally injected AMSCs did not migrate to the colon lesions, high levels of TSG6 expression and secretion were noticed both in vivo and in vitro. Similar to the role of AMSCs, injection of recombinant human TSG6 attenuated intestinal fibrosis in the mouse models, which was not observed with the administration of AMSCs with TSG6 knockdown or TSG6 neutralizing antibody. Mechanistically, TSG6 alleviates TGF-β1-stimulated upregulation of α-smooth muscle actin (αSMA) and collagen I by inhibiting Smad2 phosphorylation. Furthermore, the expression of TSG6 is lower in intestinal fibrosis tissue of patients with Crohn's disease and can reduce pro-fibrotic protein (αSMA) secretion from primary ileal fibrotic tissue.

CONCLUSIONS

AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein, which inhibits Smad2 phosphorylation. TSG6, a novel anti-fibrotic factor, could potentially improve intestinal fibrosis treatments.

Diagnostic Value and Molecular Function of MicroRNAs in Endometrial Diseases: A Systematic Review

The human endometrium experiences significant cyclic morphological and biochemical changes throughout the menstrual cycle to prepare for embryo implantation. These processes are meticulously regulated by ovarian steroids and various locally expressed genes, encompassing inflammatory reactions, apoptosis, cell proliferation, angiogenesis, differentiation (tissue formation), and tissue remodeling. MicroRNAs (miRNAs) have been recognized as crucial regulators of gene expression, with their altered expression being linked to the onset and progression of various disorders, including cancer. This review examines the expression of miRNAs in the endometrium and their potential regulatory roles under pathological conditions such as endometriosis, recurrent implantation failure and endometrial cancer. Given miRNAs' critical role in maintaining gene expression stability, understanding the regulatory mechanisms of endometrial miRNAs and identifying their specific target genes could pave the way for developing preventive and therapeutic strategies targeting specific genes associated with these reproductive disorders.

Panax notoginseng saponins improve oral submucous fibrosis by inhibiting the Wnt/β-catenin signal pathway

OBJECTIVE

Oral submucous fibrosis (OSF) is a chronic, insidious, progressive mucosal disease that may be affected by mutations in the Wnt/β-catenin signaling pathway. Panax notoginseng saponins (PNS) is a powerful anti-fibrosis agent; however, its effect and mechanism in treating OSF remain unclear. This study investigated the effect and mechanism of PNS treatment for OSF.

STUDY DESIGN

Arecoline was used to induce OSF models in vivo and in vitro, which were then treated with PNS. Hematoxylin-eosin (HE) and Masson trichrome staining were used to observe histopathology changes; E-cadherin and β-catenin were detected by Immunohistochemical assay, and type Ⅰ collagen (CollA1) and β-catenin were detected by immunofluorescent staining. The Wnt/β-catenin pathway and fibrosis signs were assessed using Western Blot and real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

The expression of CollA1, Wnt1, and β-catenin were increased, and E-cadherin, GSK-3β, and β-catenin expression were decreased in OSF models. PNS and inhibitor intervention increased E-cadherin, Wnt1, and β-catenin and decreased CollA1 and GSK-3β in a dose-dependent manner.

CONCLUSION

PNS can improve OSF by inhibiting the Wnt/β-catenin signal pathway and thus may be used as a potential medicine for the treatment of OSF.

Effects of Mesenchymal Stem Cells-Derived Extracellular Vesicles on Inhibition of Hepatic Fibrosis by Delivering miR-200a

BACKGROUND

Hepatic fibrosis (HF) is a common pathological feature of chronic hepatic diseases. We aimed to illuminate the significance of amniotic mesenchymal stem cells (AMSCs)-derived extracellular vesicles (AMSCs-EVs) in HF.

METHODS

Human AMSCs-EVs were isolated and identified. HF mice were constructed and treated with EVs. The fibrosis was observed by staining experiments and Western blot (WB) assay. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and hepatic hydroxyproline (Hyp) were detected to confirm liver function. For the in vitro experiments, human hepatic stellate cells were induced with transforming growth factor-β and treated with EVs. To measure the degree of HF, the expression of alpha-smooth muscle actin (α-SMA) and Collagen I was detected by WB assay, and cell proliferation was detected by cell counting kit 8 assay. The levels of miR-200a, Zinc finger E-box binding homeobox 1 (ZEB1), and phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) were detected by WB and real-time quantitative polymerase chain reaction. The binding of ZEB1 to PIK3R3 and miR-200a to ZEB1 was analyzed by chromatin immunoprecipitation and dual luciferase assays to validate their relationships.

RESULTS

Human AMSCs and AMSCs-EVs were obtained. Serum ALT, AST, TBIL, and hepatic Hyp were increased, implying the fibrosis degree was aggravated in HF mice, which was decreased again after EV treatment. EVs inhibited HF degree by reducing α-SMA and Collagen I and promoting cell proliferation. AMSCs-EVs delivered miR-200a into hepatocytes, which up-regulated miR-200a expression, inhibited ZEB1 expression, and reduced its enrichment on the PIK3R3 promoter, therefore inhibiting PIK3R3 expression and alleviating HF. Overexpression of ZEB1 or PIK3R3 attenuated the anti-fibrotic effect of AMSCs-EVs.

CONCLUSION

Human AMSCs-derived EVs mediated miR-200a delivery and inhibition of intracellular ZEB1/PIK3R3 axis to exert anti-fibrosis effects.

DCDC2 inhibits hepatic stellate cell activation and ameliorates CCl4-induced liver fibrosis by suppressing Wnt/β-catenin signaling

Liver fibrosis, as a consequence of chronic liver disease, involves the activation of hepatic stellate cell (HSC) caused by various chronic liver injuries. Emerging evidence suggests that activation of HSC during an inflammatory state can lead to abnormal accumulation of extracellular matrix (ECM). Investigating novel strategies to inhibit HSC activation and proliferation holds significant importance for the treatment of liver fibrosis. As a member of the doublecortin domain-containing family, doublecortin domain containing 2 (DCDC2) mutations can lead to neonatal sclerosing cholangitis, but its involvement in liver fibrosis remains unclear. Therefore, this study aims to elucidate the role of DCDC2 in liver fibrosis. Our findings revealed a reduction in DCDC2 expression in both human fibrotic liver tissues and carbon tetrachloride (CCl4)-induced mouse liver fibrotic tissues. Furthermore, exposure to transforming growth factor beta-1(TGF-β1) stimulation resulted in a dose- and time-dependent decrease in DCDC2 expression. The overexpression of DCDC2 inhibited the expression of α-smooth muscle actin (α-SMA) and type I collagen alpha 1 (Col1α1), and reduced the activation of HSC stimulated with TGF-β1. Additionally, we provided evidence that the Wnt/β-catenin signaling pathway was involved in this process, wherein DCDC2 was observed to inhibit β-catenin activation, thereby preventing its nuclear translocation. Furthermore, our findings demonstrated that DCDC2 could attenuate the proliferation and epithelial-mesenchymal transition (EMT)-like processes of HSC. In vivo, exogenous DCDC2 could ameliorate CCl4-induced liver fibrosis. In summary, DCDC2 was remarkably downregulated in liver fibrotic tissues of both humans and mice, as well as in TGF-β1-activated HSC. DCDC2 inhibited the activation of HSC induced by TGF-β1 in vitro and fibrogenic changes in vivo, suggesting that it is a promising therapeutic target for liver fibrosis and warrants further investigation in clinical practice.

The role of PI3k/AKT signaling pathway in attenuating liver fibrosis: a comprehensive review

Excessive accumulation of extracellular matrix (ECM) components within the liver leads to a pathological condition known as liver fibrosis. Alcohol abuse, non-alcoholic fatty liver disease (NAFLD), autoimmune issues, and viral hepatitis cause chronic liver injury. Exploring potential therapeutic targets and understanding the molecular mechanisms involved in liver fibrosis are essential for the development of effective interventions. The goal of this comprehensive review is to explain how the PI3K/AKT signaling pathway contributes to the reduction of liver fibrosis. The potential of this pathway as a therapeutic target is investigated through a summary of results from in vivo and in vitro studies. Studies focusing on PI3K/AKT activation have shown a significant decrease in fibrosis markers and a significant improvement in liver function. The review emphasizes how this pathway may prevent ECM synthesis and hepatic stellate cell (HSC) activation, ultimately reducing the fibrotic response. The specific mechanisms and downstream effectors of the PI3K/AKT pathway in liver fibrosis constitute a rapidly developing field of study. In conclusion, the PI3K/AKT signaling pathway plays a significant role in attenuating liver fibrosis. Its complex role in regulating HSC activation and ECM production, demonstrated both in vitro and in vivo, underscores its potential as a effective therapeutic approach for managing liver fibrosis and slowing disease progression. A comprehensive review of this field provides valuable insights into its future developments and implications for clinical applications.

LncRNA SNHG11 reprograms glutaminolysis in hepatic stellate cells via Wnt/β-catenin/GLS axis

Long non-coding RNAs (lncRNAs) have been identified as decisive regulators of liver fibrosis. Hepatic stellate cells (HSCs), major hepatic cells contributing to liver fibrosis, undergo metabolic reprogramming for transdifferentiation and activation maintenance. As a crucial part of metabolic reprogramming, glutaminolysis fuels the tricyclic acid (TCA) cycle that renders HSCs addicted to glutamine. However, how lncRNAs reprogram glutamine metabolism in HSCs is unknown. For this research, we characterized the pro-fibrogenic function of small nucleolar host gene 11 (SNHG11). Our data showed that in carbon tetrachloride (CCl4, 7 μL/g, intraperitoneally) treated C57BL/6J mice, SNHG11 expression was highly up-regulated in fibrotic livers and activated primary HSCs. SNHG11 knockdown attenuated the accumulation of fibrotic markers α-SMA and Col1A1 in liver fibrosis tissues and activated HSCs. Western blot and qRT-PCR assays demonstrated that glutaminase (GLS), the rate-limiting enzyme for glutaminolysis, was a downstream target of SNHG11. Furthermore, SNHG11 upregulated glutaminolysis in HSCs through the activation of the Wnt/β-catenin signaling pathway. The results highlighted that SNHG11 is a glutaminolysis-regulated lncRNA that promotes liver fibrosis. A novel insight into the metabolic mechanism that reprograms glutaminolysis in HSCs could be exploited as anti-fibrotic targets.

Arctium lappa L. polysaccharides enhanced the therapeutic effects of nasal ectomesenchymal stem cells against liver fibrosis by inhibiting the Wnt/β-catenin pathway

The oxidative microenvironment in fibrotic livers often diminishes the effectiveness of mesenchymal stem cells (MSCs)-based therapy. Recent research suggests that pharmacological pre-treatment could enhance the therapeutic performance of MSCs. In this study, we assessed the impact of Arctium lappa L. polysaccharides (ALP) on the biological properties of nasal ectomesenchymal stem cells (EMSCs) and investigated the augmenting effect of ALP pretreatment on EMSCs (ALP-EMSCs) for the treatment of liver fibrosis. ALP treatment demonstrated multiple biological impacts on EMSC functions regarding liver fibrosis: firstly, it maintained the stemness of the cells while boosting the EMSCs' paracrine effects; secondly, it increased the expression of anti-inflammatory and antioxidant factors; thirdly, it inhibited the activation of hepatic stellate cells (HSCs) and liver collagen build-up by modulating the Wnt/β-catenin signaling pathways. Collectively, these effects helped to halt the progression of liver fibrosis. Therefore, the use of ALP-EMSCs presents an innovative and promising approach for treating hepatic fibrosis in clinical scenarios.

Amnion-derived hydrogels as a versatile platform for regenerative therapy: from lab to market

In recent years, the amnion (AM) has emerged as a versatile tool for stimulating tissue regeneration and has been of immense interest for clinical applications. AM is an abundant and cost-effective tissue source that does not face strict ethical issues for biomedical applications. The outstanding biological attributes of AM, including side-dependent angiogenesis, low immunogenicity, anti-inflammatory, anti-fibrotic, and antibacterial properties facilitate its usage for tissue engineering and regenerative medicine. However, the clinical usage of thin AM sheets is accompanied by some limitations, such as handling without folding or tearing and the necessity for sutures to keep the material over the wound, which requires additional considerations. Therefore, processing the decellularized AM (dAM) tissue into a temperature-sensitive hydrogel has expanded its processability and applicability as an injectable hydrogel for minimally invasive therapies and a source of bioink for the fabrication of biomimetic tissue constructs by recapitulating desired biochemical cues or pre-defined architectural design. This article reviews the multi-functionality of dAM hydrogels for various biomedical applications, including skin repair, heart treatment, cartilage regeneration, endometrium regeneration, vascular graft, dental pulp regeneration, and cell culture/carrier platform. Not only recent and cutting-edge research is reviewed but also available commercial products are introduced and their main features and shortcomings are elaborated. Besides the great potential of AM-derived hydrogels for regenerative therapy, intensive interdisciplinary studies are still required to modify their mechanical and biological properties in order to broaden their therapeutic benefits and biomedical applications. Employing additive manufacturing techniques (e.g., bioprinting), nanotechnology approaches (e.g., inclusion of various bioactive nanoparticles), and biochemical alterations (e.g., modification of dAM matrix with photo-sensitive molecules) are of particular interest. This review article aims to discuss the current function of dAM hydrogels for the repair of target tissues and identifies innovative methods for broadening their potential applications for nanomedicine and healthcare.

Therapeutic potential of stem cells in regeneration of liver in chronic liver diseases: Current perspectives and future challenges

The deposition of extracellular matrix and hyperplasia of connective tissue characterizes chronic liver disease called hepatic fibrosis. Progression of hepatic fibrosis may lead to hepatocellular carcinoma. At this stage, only liver transplantation is a viable option. However, the number of possible liver donors is less than the number of patients needing transplantation. Consequently, alternative cell therapies based on non-stem cells (e.g., fibroblasts, chondrocytes, keratinocytes, and hepatocytes) therapy may be able to postpone hepatic disease, but they are often ineffective. Thus, novel stem cell-based therapeutics might be potentially important cutting-edge approaches for treating liver diseases and reducing patient' suffering. Several signaling pathways provide targets for stem cell interventions. These include pathways such as TGF-β, STAT3/BCL-2, NADPH oxidase, Raf/MEK/ERK, Notch, and Wnt/β-catenin. Moreover, mesenchymal stem cells (MSCs) stimulate interleukin (IL)-10, which inhibits T-cells and converts M1 macrophages into M2 macrophages, producing an anti-inflammatory environment. Furthermore, it inhibits the action of CD4+ and CD8+ T cells and reduces the activity of TNF-α and interferon cytokines by enhancing IL-4 synthesis. Consequently, the immunomodulatory and anti-inflammatory capabilities of MSCs make them an attractive therapeutic approach. Importantly, MSCs can inhibit the activation of hepatic stellate cells, causing their apoptosis and subsequent promotion of hepatocyte proliferation, thereby replacing dead hepatocytes and reducing liver fibrosis. This review discusses the multidimensional therapeutic role of stem cells as cell-based therapeutics in liver fibrosis.

Accumulation of senescent cells in the stroma of aged mouse ovary

Senescent cells play a detrimental role in age-associated pathogenesis by producing factors involved in senescence-associated secretory phenotype (SASP). The present study was conducted to examine the possibility that senescent cells are present in aged ovaries and, if so, to determine the tissue region where senescent cells accumulate using a mouse model. Female mice at 2-4 and 8-10 months were used as reproductively young and aged models, respectively; the latter included mice with and without reproductive experience. Cells positive for senescence-associated β-galactosidase (SA-β-Gal) staining, one of the markers of cellular senescence, were detected in the stromal region of aged, but not young, ovaries regardless of reproductive experience. Likewise, the localization of cells expressing CDKN2A (cyclin dependent kinase inhibitor 2A), another senescence marker, in the stromal region of aged ovaries was detected with immunohistochemistry. CDKN2A expression detected by western blotting was significantly higher in the ovaries of aged mice with reproductive experience than in those without the experience. Moreover, cells positive for both γH2AX (a senescence marker) and fluorescent SA-β-Gal staining were present in those isolated from aged ovaries. In addition, the transcript levels of several SASP factors were significantly increased in aged ovaries. These results suggest that senescent cells accumulate in the ovarian stroma and may affect ovarian function in aged mice. Additionally, reproductive experience may promote accumulation.

Application of the Human Amniotic Membrane as an Adjuvant Therapy for the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related morbidity and mortality worldwide. Current therapeutic approaches suffer significant side effects and lack of clear understanding of their molecular targets. Recent studies reported the anticancer effects, immunomodulatory properties, and antiangiogenic effects of the human amniotic membrane (hAM). hAM is a transparent protective membrane that surrounds the fetus. Preclinical studies showed pro-apoptotic and antiproliferative properties of hAM treatment on cancer cells. Herein, we present the latest findings of the application of the hAM in combating HCC tumorigenesis and the underlying molecular pathogenies and the role of transforming growth factor-beta (TGFβ), P53, WNT/beta-catenin, and PI3K/AKT pathways. The emerging clinical applications of hAM in cancer therapy provide evidence for its diverse and unique features and suitability for the management of a wide range of pathological conditions.

SKIL/SnoN attenuates TGF-β1/SMAD signaling-dependent collagen synthesis in hepatic fibrosis

The ski-related novel gene (SnoN), encoded by the SKIL gene, has been shown to negatively regulated transforming growth factor-β1 (TGF-β1) signaling pathway. However, the roles of SnoN in hepatic stellate cell (HSC) activation and hepatic fibrosis (HF) are still unclear. To evaluate the role of SnoN in HF, we combined bulk RNA sequencing analysis and single-cell RNA sequencing analysis to analyse patients with HF. The role of SKIL/SnoN was verified using liver samples from rat model transfected HSC-T6 and LX-2 cell lines. Immunohistochemistry, immunofluorescence, PCR, and western blotting techniques were used to demonstrate the expression of SnoN and its regulatory effects on TGF-β1 signaling in fibrotic liver tissues and cells. Furthermore, we constructed competitive endogenous RNA regulatory network and potential drug network associated with the SnoN gene. We identified SKIL gene as a differentially expressed gene in hepatic fibrosis. SnoN protein was found to be widely expressed in the cytoplasm of normal hepatic tissues, whereas it was almost absent in HF tissues. In the rat group subjected to bile duct ligation (BDL), SnoN protein expression decreased, while TGF-β1, collagen III, tissue inhibitor of metalloproteinase 1 (TIMP-1), and fibronectin levels increased. We observed the interaction of SnoN with p-SMAD2 and p-SMAD3 in the cytoplasm. Following SnoN overexpression, apoptosis of HSCs was promoted, and the expression of HF-associated proteins, including collagen I, collagen III, and TIMP-1, was reduced. Conversely, downregulation of SnoN inhibited HSC apoptosis, increased collagen III and TIMP-1 levels, and decreased matrix metalloproteinase 13 (MMP-13) expression. In conclusion, SnoN expression is downregulated in fibrotic livers, and could attenuate TGF-β1/SMADs signaling-dependent de-repression of collagen synthesis.

Biological importance of human amniotic membrane in tissue engineering and regenerative medicine

The human amniotic membrane (hAM) is the innermost layer of the placenta. Its distinctive structure and the biological and physical characteristics make it a highly biocompatible material in a variety of regenerative medicine applications. It also acts as a supply of bioactive factors and cells, which indicate the advantages over other tissues. In this review, we firstly discussed the biological properties of hAM-derived cells in vivo or in vitro, along with their stemness of markers, pointing out a promising source of stem cells for regenerative medicine. Then, we systematically summarized current knowledge on the collection, preparation, preservation, and decellularization of hAM, as well as their characteristics helping to improve the understanding of applications in tissue engineering. Finally, we highlighted the recent advances in which hAM has undergone additional modifications to achieve an adequate perspective of regenerative medicine applications. More investigations are required in utilizing appropriate modifications to enhance the therapeutic effectiveness of hAM in the future.

Immunomodulatory Role of Mesenchymal Stem Cells in Liver Transplantation: Status and Prospects

BACKGROUND

Liver transplantation (LT) is the only effective therapy for end-stage liver diseases, but some patients usually present with serious infection and immune rejection. Those with immune rejection require long-term administration of immunosuppressants, leading to serious adverse effects. Mesenchymal stem cells (MSCs) have various advantages in immune regulation and are promising drugs most likely to replace immunosuppressants.

SUMMARY

This study summarized the application of MSCs monotherapy, its combination with immunosuppressants, MSCs genetic modification, and MSCs derivative therapy (cell-free therapy) in LT. This may deepen the understanding of immunomodulatory role of MSCs and promote the application of MSCs in immune rejection treatment after LT.

KEY MESSAGES

MSCs could attenuate ischemia-reperfusion injury and immune rejection. There is no consensus on the effects of types and concentrations of immunosuppressants on MSCs. Although genetically modified MSCs have contributed to better outcomes to some extent, the best modification is still unclear. Besides, multiple clinical complications developed frequently after LT. Unfortunately, there are still few studies on the polygenic modification of MSCs for the simultaneous treatment of these complications. Therefore, more studies should be performed to investigate the potency of multi-gene modified MSCs in treating complications after LT. Additionally, MSC derivatives mainly include exosomes, extracellular vesicles, and conditioned medium. Despite therapeutic effects, these three therapies still have some limitations such as heterogeneity between generations and that they cannot be quantified accurately.

Human embryonic stem cell-derived mesenchymal stem cell secretome reverts silica-induced airway epithelial cell injury by regulating Bmi1 signaling

Silicosis is an irreversible chronic pulmonary disease caused by long-term inhalation and deposition of silica particles, which is currently incurable. The exhaustion of airway epithelial stem cells plays a pathogenetic role in silicosis. In present study, we investigated therapeutic effects and potential mechanism of human embryonic stem cell (hESC)-derived MSC-likes immune and matrix regulatory cells (IMRCs) (hESC-MSC-IMRCs), a type of manufacturable MSCs for clinical application in silicosis mice. Our results showed that the transplantation of hESC-MSC-IMRCs led the alleviation of silica-induced silicosis in mice, accompanied by inhibiting epithelia-mesenchymal transition (EMT), activating B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi1) signaling and airway epithelial cell regeneration. In consistence, the secretome of hESC-MSC-IMRC exhibited abilities to restore the potency and plasticity of primary human bronchial epithelial cells (HBECs) proliferation and differentiation following the SiO2 -induced HBECs injury. Mechanistically, the secretome resolved the SiO2 -induced HBECs injury through the activation of BMI1 signaling and restoration of airway basal cell proliferation and differentiation. Moreover, the activation of BMI1 significantly enhanced the capacity of HBEC proliferation and differentiation to multiple airway epithelial cell types in organoids. Cytokine array revealed that DKK1, VEGF, uPAR, IL-8, Serpin E1, MCP-1 and Tsp-1 were the main factors in the hESC-MSC-IMRC secretome. These results demonstrated a potential therapeutic effect of hESC-MSC-IMRCs and their secretome for silicosis, in part through a mechanism by activating Bmi1 signaling to revert the exhaustion of airway epithelial stem cells, subsequentially enhance the potency and plasticity of lung epithelial stem cells.

Molecular pathogenesis of subretinal fibrosis in neovascular AMD focusing on epithelial-mesenchymal transformation of retinal pigment epithelium

Age-related macular degeneration (AMD) is a leading cause of vision loss among elderly people in developed countries. Neovascular AMD (nAMD) accounts for more than 90% of AMD-related vision loss. At present, intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) is widely used as the first-line therapy to decrease the choroidal and retinal neovascularizations, and thus to improve or maintain the visual acuity of the patients with nAMD. However, about 1/3 patients still progress to irreversible visual impairment due to subretinal fibrosis even with adequate anti-VEGF treatment. Extensive literatures support the critical role of epithelial-mesenchymal transformation (EMT) of retinal pigment epithelium (RPE) in the pathogenesis of subretinal fibrosis in nAMD, but the underlying mechanisms still remain largely unknown. This review summarized the molecular pathogenesis of subretinal fibrosis in nAMD, especially focusing on the transforming growth factor-β (TGF-β)-induced EMT pathways. It was also discussed how these pathways crosstalk and respond to signals from the microenvironment to mediate EMT and contribute to the progression of nAMD-related subretinal fibrosis. Targeting EMT signaling pathways might provide a promising and effective therapeutic strategy to treat subretinal fibrosis secondary to nAMD.

Amniotic Membrane and Its Derivatives: Novel Therapeutic Modalities in Liver Disorders

The liver is a vital organ responsible for metabolic and digestive functions, protein synthesis, detoxification, and numerous other necessary functions. Various acute, chronic, and neoplastic disorders affect the liver and hamper its biological functions. Most of the untreated liver diseases lead to inflammation and fibrosis which develop into cirrhosis. The human amniotic membrane (hAM), the innermost layer of the fetal placenta, is composed of multiple layers that include growth-factor rich basement membrane, epithelial and mesenchymal stromal cell layers. hAM possesses distinct beneficial anti-fibrotic, anti-inflammatory and pro-regenerative properties via the secretion of multiple potent trophic factors and/or direct differentiation into hepatic cells which place hAM-based therapies as potential therapeutic strategies for the treatment of chronic liver diseases. Decellularized hAM is also an ideal scaffold for liver tissue engineering as this biocompatible niche provides an excellent milieu for cell proliferation and hepatocytic differentiation. Therefore, the current review discusses the therapeutic potential of hAM and its derivatives in providing therapeutic solutions for liver pathologies including acute liver failure, metabolic disorders, liver fibrosis as well as its application in liver tissue engineering.

METTL14 reverses liver fibrosis by inhibiting NOVA2 through an m6A-YTHDF2-dependent mechanism

BACKGROUND

N6-methyladenosine (m6A), the most prevalent internal RNA modification in eukaryotic cells, is dynamically regulated in response to a wide range of physiological and pathological states. Nonetheless, the involvement of METTL14-induced m6A in liver fibrosis (LF) has yet to be established.

METHODS

In vitro, HSC cell lines with knock-down and overexpression of METTL14 were constructed, and the effects of METTL14 gene on the phenotypic function of activated HSCs were observed. The proliferation rate was measured by CCK8 and EDU, the cell proliferation cycle was measured by flow detector, the migration rate was measured by Transwell, and the contractility of F-actin was observed after phalloidin staining. The downstream target gene NOVA2 of METTL14 was screened by combined sequencing of MeRIP-seq and RNA-seq, combined with signal analysis. Adeno-associated virus (AAV) was injected into the tail vein in vivo to knock down the expression of METTL14, so as to further observe the role of METTL14 in the progress of LF.

RESULTS

our research showed that the methylase METTL14 content was decreased in hepatic tissue from patients with LF, leading to a lowered degree of m6A modification. Functionally, we discovered that knocking down m6A methyltransferase METTL14 led to increased HSC activation and a substantial worsening of LF. Mechanically, as shown in a multiomics study of HSCs, depleting METTL14 levels decreased m6A deposition onNOVA2 mRNA transcripts, which prompted the activation of YTHDF2 to detect and degrade the decrease of NOVA2 mRNA.

CONCLUSIONS

METTL14 functioned as a profibrotic gene by suppressing NOVA2 activity in a mechanism dependent on m6A-YTHDF2. Moreover, knocking down METTL14 exacerbated LF, while NOVA2 prevented its development and partly reversed the damage.

Treatment of liver fibrosis: Past, current, and future

Liver fibrosis accompanies the progression of chronic liver diseases independent of etiologies, such as hepatitis viral infection, alcohol consumption, and metabolic-associated fatty liver disease. It is commonly associated with liver injury, inflammation, and cell death. Liver fibrosis is characterized by abnormal accumulation of extracellular matrix components that are expressed by liver myofibroblasts such as collagens and alpha-smooth actin proteins. Activated hepatic stellate cells contribute to the major population of myofibroblasts. Many treatments for liver fibrosis have been investigated in clinical trials, including dietary supplementation (e.g., vitamin C), biological treatment (e.g., simtuzumab), drug (e.g., pegbelfermin and natural herbs), genetic regulation (e.g., non-coding RNAs), and transplantation of stem cells (e.g., hematopoietic stem cells). However, none of these treatments has been approved by Food and Drug Administration. The treatment efficacy can be evaluated by histological staining methods, imaging methods, and serum biomarkers, as well as fibrosis scoring systems, such as fibrosis-4 index, aspartate aminotransferase to platelet ratio, and non-alcoholic fatty liver disease fibrosis score. Furthermore, the reverse of liver fibrosis is slowly and frequently impossible for advanced fibrosis or cirrhosis. To avoid the life-threatening stage of liver fibrosis, anti-fibrotic treatments, especially for combined behavior prevention, biological treatment, drugs or herb medicines, and dietary regulation are needed. This review summarizes the past studies and current and future treatments for liver fibrosis.

Dynamic expression of IGFBP3 modulate dual actions of mineralization micro-environment during tooth development via Wnt/beta-catenin signaling pathway

BACKGROUND

Tooth development, as one of the major mineralized tissues in the body, require fine-tuning of mineralization micro-environment. The interaction between dental epithelium and mesenchyme plays a decisive role in this process. With epithelium-mesenchyme dissociation study, we found interesting expression pattern of insulin-like growth factor binding protein 3 (IGFBP3) in response to disruption of dental epithelium-mesenchyme interaction. Its action and related mechanisms as regulator of mineralization micro-environment during tooth development are investigated.

RESULTS

Expressions of osteogenic markers at early stage of tooth development are significantly lower than those at later stage. BMP2 treatment further confirmed a high mineralization micro-environment is disruptive at early stage, but beneficial at later stage of tooth development. In contrast, IGFBP3's expression increased gradually from E14.5, peaked at P5, and decreased afterwards, demonstrating an inverse correlation with osteogenic markers. RNA-Seq and Co-immunoprecipitation showed that IGFBP3 regulates the Wnt/beta-catenin signaling pathway activity by enhancing DKK1 expression and direct protein-protein interaction. The suppression of the mineralization microenvironment effectuated by IGFBP3 could be reversed by the DKK1 inhibitor WAY-262611, further demonstrating that IGFBP3 exerted its influence via DKK1.

CONCLUSION

A deeper understanding of tooth development mechanisms is essential for tooth regeneration, which have great implications for dental care. The current study demonstrated that the IGFBP3 expression is regulated in accordance with the needs of the mineralization microenvironment during tooth development, and IGFBP3 exerts its modulating action on osteogenic/odontogenic differentiation of hDPSCs by DKK1-Wnt/ beta-catenin axis.

S1PR2/Wnt3a/RhoA/ROCK1/β-catenin signaling pathway promotes diabetic nephropathy by inducting endothelial mesenchymal transition and impairing endothelial barrier function

AIMS

Hyperglycemia and hyperlipidemia are key factors in the pathogenesis of diabetic nephropathy (DN), and renal fibrosis is the most common pathway leading to the disease. Endothelial mesenchymal transition (EndMT) is a crucial mechanism for the production of myofibroblasts, and impaired endothelial barrier function is one of the mechanisms for the generation of microalbuminuria in DN. However, the specific mechanisms behind these are not yet clear.

MAIN METHODS

Protein expression was detected by immunofluorescence, immunohistochemistry and Western blot. Knocking down or pharmacological inhibition of S1PR2 were used to inhibit Wnt3a, RhoA, ROCK1, β-catenin, and Snail signaling. Changes in cell function were analyzed by CCK-8 method, cell scratching assay, FITC-dextran permeability assay, and Evans blue staining.

KEY FINDINGS

Consistent with increased gene expression of S1PR2 in DN patients and mice with kidney fibrosis disease, S1PR2 expression was significantly increased in glomerular endothelial cells of DN mice and HUVEC cells treated with glucolipids. Knocking down or pharmacological inhibition of S1PR2 significantly decreased the expression of Wnt3a, RhoA, ROCK1, and β-catenin in endothelial cells. Furthermore, inhibition of S1PR2 in vivo reversed EndMT and endothelial barrier dysfunction in glomerular endothelial cells. Inhibition of S1PR2 and ROCK1 in vitro also reversed EndMT and endothelial barrier dysfunction in endothelial cells.

SIGNIFICANCE

Our results suggest that the S1PR2/Wnt3a/RhoA/ROCK1/β-catenin signaling pathway is involved in the pathogenesis of DN by inducing EndMT and endothelial barrier dysfunction.

Phillygenin Ameliorates Carbon Tetrachloride-Induced Liver Fibrosis: Suppression of Inflammation and Wnt/β-Catenin Signaling Pathway

Liver fibrosis (LF) is caused by the chronic wound healing response to liver injury from various origins. Among the causes, inflammatory response is the central trigger of LF. Phillygenin (PHI) is a lignan derived from Forsythia suspensa, which has significant anti-inflammatory properties. However, the effect of PHI on improving LF and the underlying mechanism have rarely been studied. In this study, we used carbon tetrachloride (CCl₄) to establish a mouse model of LF. Through histological analysis of liver tissue, and measurement of the levels of hepatocyte damage markers (ALT, AST, TBIL, TBA) and four indicators of LF (Col IV, HA, LN, PC-III) in serum, it was shown that PHI improved liver function and reduced the progress of LF. Subsequently, the detection of fibrogenic biomarkers in liver tissue showed that PHI inhibited the activation of hepatic stellate cells (HSCs). Next, the expression of inflammatory markers in liver tissue/serum was detected by immunohistochemistry, RT-qPCR, and ELISA, suggesting that PHI inhibited inflammation during LF. Similarly, in vitro experiments also confirmed that PHI could inhibit lipopolysaccharide-induced inflammatory responses in RAW264.7 cells, which showed strong anti-inflammatory effects. In addition, the results of network pharmacology, molecular docking, RT-qPCR and western blot confirmed that PHI could alleviate CCl₄-induced LF by inhibiting the Wnt/β-catenin pathway. In conclusion, our research showed that PHI curbed LF through inhibition of HSC activation and collagen accumulation via inhibiting multiple profibrogenic factors, modulating a variety of inflammatory factors, and suppressing the Wnt/β-catenin pathway.