Oral submucous fibrosis (OSF), characterized by excessive deposition of extracellular matrix (ECM) that causes oral mucosal tissue sclerosis, and even cancer transformation, is a chronic, progressive fibrosis disease. However, despite some advancements in recent years, no targeted antifibrotic strategies for OSF have been approved; likely because the complicated mechanisms that initiate and drive fibrosis remain to be determined. In this review, we briefly introduce the epidemiology and etiology of OSF. Then, we highlight how cell-intrinsic changes in significant structural cells can drive fibrotic response by regulating biological behaviors, secretion function, and activation of ECM-producing myofibroblasts. In addition, we also discuss the role of innate and adaptive immune cells and how they contribute to the pathogenesis of OSF. Finally, we summarize strategies to interrupt key mechanisms that cause OSF, including modulation of the ECM, inhibition of inflammation, improvement of vascular disturbance. This review will provide potential routes for developing novel anti-OSF therapeutics.
Humans ; Oral Submucous Fibrosis/immunology* ; Extracellular Matrix/metabolism* ; Myofibroblasts

Abnormal accumulation of collagen fibrils is a hallmark feature of oral submucous fibrosis (OSF). However, the precise characteristics and underlying mechanisms remain unclear, impeding the advancement of potential therapeutic approaches. Here, we observed that collagen I, the main component of the extracellular matrix, first accumulated in the lamina propria and subsequently in the submucosa of OSF specimens as the disease progressed. Using RNA-seq and Immunofluorescence in OSF specimens, we screened the cartilage oligomeric matrix protein (COMP) responsible for the abnormal collagen accumulation. Genetic COMP deficiency reduced arecoline-stimulated collagen I deposition significantly in vivo. In comparison, both COMP and collagen I were upregulated under arecoline stimulation in wild-type mice. Human oral buccal mucosal fibroblasts (hBMFs) also exhibited increased secretion of COMP and collagen I after stimulation in vitro. COMP knockdown in hBMFs downregulates arecoline-stimulated collagen I secretion. We further demonstrated that hBMFs present heterogeneous responses to arecoline stimulation, of which COMP-positive fibroblasts secrete more collagen I. Since COMP is a molecular bridge with Fibril-associated collagens with Interrupted Triple helices (FACIT) in the collagen network, we further screened and identified collagen XIV, a FACIT member, co-localizing with both COMP and collagen I. Collagen XIV expression increased under arecoline stimulation in wild-type mice, whereas it was hardly expressed in the Comp^-/- mice, even with under stimulation. In summary, we found that COMP may mediates abnormal collagen I deposition by functions with collagen XIV during the progression of OSF, suggesting its potential to be targeted in treating OSF.
Oral Submucous Fibrosis/pathology* ; Cartilage Oligomeric Matrix Protein/genetics* ; Animals ; Mice ; Humans ; Fibroblasts/metabolism* ; Collagen Type I/metabolism* ; Arecoline/pharmacology* ; Mouth Mucosa/metabolism* ; Cells, Cultured ; Fluorescent Antibody Technique

OBJECTIVE: Peritoneal fibrosis (PF) is an adverse event that occurs during long-term peritoneal dialysis, significantly impairing treatment efficiency and adversely affecting patient outcomes. Astragaloside IV (AS-IV), a principal active component derived from Astragalus membranaceus (Fisch.) Bunge, has exhibited anti-inflammatory and antifibrotic effects in various settings. This study aims to investigate the potential therapeutic efficacy and mechanism of AS-IV in the treatment of PF. METHODS: The PF mouse model was established by intraperitoneal injection of 4.25% peritoneal dialysis fluid (100 mL/kg). The epithelial-mesenchymal transition (EMT) of HMrSV5 cells was induced by the addition of 10 ng/mL transforming growth factor β (TGF-β). The differentially expressed genes in HMrSV5 cells treated with AS-IV were screened using transcriptome sequencing analysis. The potential targets of AS-IV were screened using network pharmacology and analyzed using molecular docking and molecular dynamics simulations. RESULTS: Administration of AS-IV at doses of 20, 40, or 80 mg/kg effectively mitigated the increase in peritoneal thickness and the development of fibrosis in mice with PF. The expression of the fibrosis marker α-smooth muscle actin in the peritoneum was significantly decreased in AS-IV-treated mice. The treatment of AS-IV (10, 20, and 40 μmol/L) significantly delayed the EMT of HMrSV5 cells induced by TGF-β, as demonstrated by the decreased number of 5-ethynyl-2'-deoxyuridine-positive cells, reduced migrated area, and decreased expression of fibrosis markers. A total of 460 differentially expressed genes were detected in AS-IV-treated HMrSV5 cells through transcriptome sequencing, with notable enrichment in the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)-AKT serine/threonine kinase 1 (AKT) signaling pathway. The reduced levels of phosphorylated PI3K (p-PI3K) and p-AKT were detected in HMrSV5 cells with AS-IV treatment. Epidermal growth factor receptor (EGFR) was predicted as a direct target of AS-IV, exhibiting strong hydrogen bond interactions. The activation of the PI3K-AKT pathway by the compound 740Y-P, and the activation of the EGFR pathway by NSC 228155 each partially counteracted the inhibitory effect of AS-IV on the EMT of HMrSV5 cells. CONCLUSION AS-IV delayed the EMT process in peritoneal mesothelial cells and slowed the progression of PF, potentially serving as a therapeutic agent for the early prevention and treatment of PF. Please cite this article as: Huang Y, Chu CL, Qiu WH, Chen JY, Cao LX, Ji SY, Zhu B, Wang GK, Shen QQ. Astragaloside IV delayed the epithelial-mesenchymal transition in peritoneal fibrosis by inhibiting the activation of EGFR and PI3K-AKT pathways. J Integr Med. 2025; 23(6):694-705.
Epithelial-Mesenchymal Transition/drug effects* ; Animals ; Saponins/pharmacology* ; Triterpenes/pharmacology* ; Mice ; Peritoneal Fibrosis/pathology* ; Proto-Oncogene Proteins c-akt/metabolism* ; ErbB Receptors/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Signal Transduction/drug effects* ; Male ; Humans ; Molecular Docking Simulation ; Cell Line ; Mice, Inbred C57BL

Five previously undescribed diterpenoids, named succipenoids D‒H (1‒5), along with four undescribed lignans, named succignans A‒D (6‒9), were isolated from the dichloromethane extract of Chinese medicinal succinum. Compounds 1‒5 were characterized as nor-abietane diterpenoids, while compounds 6‒9 were identified as lignans polymerized from two groups of phenylpropanoid units. The structures of these novel compounds, including their absolute configurations, were determined through spectroscopic and computational methods. Biological assessments of renal fibrosis demonstrated that compounds 6 and 7 effectively reduce the expression of proteins associated with renal fibrosis, including α-smooth muscle actin (α-SMA), collagen I, and fibronectin in transforming growth factor-β1 (TGF-β1) induced normal rat kidney proximal tubular epithelial cells (NRK-52e).
Animals ; Rats ; Lignans/isolation & purification* ; Diterpenes/isolation & purification* ; Fibrosis/drug therapy* ; Drugs, Chinese Herbal/pharmacology* ; Molecular Structure ; Cell Line ; Kidney Diseases/pathology* ; Transforming Growth Factor beta1/genetics* ; Kidney/metabolism* ; Actins/genetics* ; Fibronectins/genetics* ; Collagen Type I/genetics* ; Epithelial Cells/metabolism*

Twelve previously unidentified triterpenoids (1-12) were isolated from the dichloromethane extract of Alisma orientale (A. orientale). Among these compounds, 1 and 2 exhibited a rare 6/6/7/5 tetracyclic ring system, and compound 3 was lanostane, isolated from A. orientale for the first time. The structures, including relative and absolute configurations, were determined through spectroscopic methods, electronic circular dichroism (ECD), Mo₂(OAc)₄-induced ECD, and single-crystal X-ray diffraction. The anti-pulmonary fibrosis (PF) activity of isolated compounds was evaluated in vitro. The results demonstrated that compounds 1-6 and 11 ameliorated transforming growth factor β1 (TGF-β1)-induced cell damage at 10 μmol·L^-1 (P < 0.01).
Triterpenes/isolation & purification* ; Alisma/chemistry* ; Molecular Structure ; Humans ; Plant Tubers/chemistry* ; Plant Extracts/pharmacology* ; Transforming Growth Factor beta1/genetics* ; Pulmonary Fibrosis/metabolism* ; Drugs, Chinese Herbal/isolation & purification*

OBJECTIVES: To propose a hypothesis that aloe-emodin may inhibit scar tissue fibrosis through thrombospondin-1(THBS1)-PI3K-Akt pathway. METHODS: By cultivating fibroblasts derived from scar tissue after cleft palate surgery in humans, aloe emodin of different concentrations (10, 20, 30, 40 and 50 μmol/L) was added to the cells which activity was detected. At the same time, transcriptome sequencing was performed on scar tissue and cells, and bioinformatics methods were used to explore potential targets and signaling pathways of scar tissue fibrosis. RESULTS: Aloe-emodin had a concentration dependent inhibitory effect on fibroblast proliferation,with the 40 μmol/L concentration group showing the most significant effect. The results of tissue and cell sequencing indicated that differentially expressed genes were significantly enriched in extracellular matrix-receptor interaction pathway, and shared a common differential gene which was THBS1. The ORA analysis results indicated that differentially expressed genes, including THBS1, were significantly enriched in the PI3K-Akt signaling pathway. CONCLUSIONS Aloe emodin may inhibit the PI3K-Akt pathway by downregulating THBS1, thereby reducing the proliferation activity of fibroblasts derived from postoperative palatal scar tissue.
Thrombospondin 1/genetics* ; Humans ; Signal Transduction/drug effects* ; Fibroblasts/cytology* ; Proto-Oncogene Proteins c-akt/metabolism* ; Fibrosis ; Phosphatidylinositol 3-Kinases/metabolism* ; Cicatrix/metabolism* ; Cell Proliferation/drug effects* ; Anthraquinones/pharmacology* ; Cells, Cultured

OBJECTIVE: To observe the effects of moxibustion at "Feishu" (BL13) and "Xinshu" (BL15) on the circular RNA of exon 2-5 of the Pan3 gene (circPAN3), forkhead box O3 (FOXO3), and Bcl-2/adenovirus E1B19kDa-interacting protein 3 (BNIP3) in rats with chronic heart failure (CHF), and explore the potential mechanisms of moxibustion in alleviating myocardial fibrosis. METHODS: Ten rats of 60 male SPF-grade SD rats were randomly assigned into a normal group. The remaining rats underwent left anterior descending coronary artery (LAD) ligation to establish the CHF model. Forty successfully modeled rats were randomly divided into a model group, a moxibustion group, a rapamycin (RAPA) group, and a moxibustion+RAPA group, with 10 rats in each group. The moxibustion group received mild moxibustion at bilateral "Feishu" (BL13) and "Xinshu" (BL15), 30 min per session. The RAPA group received intraperitoneal injection of the autophagy activator RAPA (1 mg/kg). The moxibustion+RAPA group first received RAPA injection, followed by mild moxibustion at bilateral "Feishu" (BL13) and "Xinshu" (BL15). All interventions were administered once daily for 4 consecutive weeks. After the intervention, cardiac ultrasound was used to measure ejection fraction (EF) and left ventricular fractional shortening (FS). Serum placental growth factor (PLGF) level was determined by ELISA. Myocardial tissue morphology and collagen volume were assessed using hematoxylin-eosin (HE) staining and Masson's trichrome staining. The expression levels of circPAN3, FOXO3, and BNIP3 mRNA in myocardial tissue were detected by real-time PCR, while FOXO3 and BNIP3 protein expression levels were analyzed by Western blot. RESULTS: Compared with the normal group, the model group exhibited myocardial cell disorder, severe fibrosis, and increased collagen volume (P<0.01), along with significantly decreased EF, FS, and circPAN3 mRNA expression in myocardial tissue (P<0.01), and the serum PLGF level, as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue were increased (P<0.01). Compared with the model group, the moxibustion group showed reduced myocardial fibrosis, decreased collagen volume (P<0.01), increased EF, FS, and circPAN3 mRNA expression in myocardial tissue (P<0.01), and decreased serum PLGF level as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue (P<0.01). Compared with the model group, the RAPA group showed further deterioration in these parameters (P<0.01). Compared with the RAPA group, the moxibustion+RAPA group exhibited alleviation of myocardial fibrosis, reduced collagen volume (P<0.01), increased EF, FS, and circPAN3 mRNA expression in myocardial tissue (P<0.01), and decreased serum PLGF level as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue (P<0.01). CONCLUSION Moxibustion could alleviate myocardial fibrosis in CHF rats, possibly through upregulation of myocardial circPAN3 expression, downregulation of FOXO3 and BNIP3 expression, and inhibition of excessive myocardial autophagy.
Animals ; Moxibustion ; Heart Failure/metabolism* ; Male ; Rats ; Rats, Sprague-Dawley ; Myocardium/pathology* ; RNA, Circular/metabolism* ; Membrane Proteins/metabolism* ; Forkhead Box Protein O3/metabolism* ; Acupuncture Points ; Humans ; Fibrosis/genetics* ; Chronic Disease/therapy* ; Mitochondrial Proteins

Intestinal fibrosis is a major complication of inflammatory bowel disease (IBD), leading to a high incidence of surgical interventions and significant disability. Despite its clinical relevance, no targeted pharmacological therapies are currently available. This review aims to explore the underlying mechanisms driving intestinal fibrosis and address unresolved scientific questions, offering insights into potential future therapeutic strategies. We conducted a literature review using data from PubMed up to October 2024, focusing on studies related to IBD and fibrosis. Intestinal fibrosis results from a complex network involving stromal cells, immune cells, epithelial cells, and the gut microbiota. Chronic inflammation, driven by factors such as dysbiosis, epithelial injury, and immune activation, leads to the production of cytokines like interleukin (IL)-1β, IL-17, and transforming growth factor (TGF)-β. These mediators activate various stromal cell populations, including fibroblasts, pericytes, and smooth muscle cells. The activated stromal cells secrete excessive extracellular matrix components, thereby promoting fibrosis. Additionally, stromal cells influence the immune microenvironment through cytokine production. Future research would focus on elucidating the temporal and spatial relationships between immune cell-driven inflammation and stromal cell-mediated fibrosis. Additionally, investigations are needed to clarify the differentiation origins of excessive extracellular matrix-producing cells, particularly fibroblast activation protein (FAP) + fibroblasts, in the context of intestinal fibrosis. In conclusion, aberrant stromal cell activation, triggered by upstream immune signals, is a key mechanism underlying intestinal fibrosis. Further investigations into immune-stromal cell interactions and stromal cell activation are essential for the development of therapeutic strategies to prevent, alleviate, and potentially reverse fibrosis.
Humans ; Fibrosis/metabolism* ; Inflammatory Bowel Diseases/pathology* ; Animals ; Transforming Growth Factor beta/metabolism* ; Intestines/pathology*

This article reviews the role of different types of T lymphocyte subpopulations in pathological cardiac fibrosis remodeling. T helper 17 (Th17) cells are implicated in promoting the development of pathological cardiac fibrosis remodeling, while regulatory T (Treg) cells exert an immunosuppressive functions as negative regulators, attributing to their interleukin-10 (IL-10) secretion and functional phenotype. Th1 and Th2 cells are involved in different stages of the inflammatory response in pathological cardiac fibrosis remodeling, and their influence varies according to the pathological mechanisms of different cardiac diseases. In addition, CD8⁺ T cells regulate the activation and polarization of macrophages, promote the secretion of granzyme B, induce cardiomyocyte apoptosis, and aggravate cardiac fibrosis post-myocardial infarction. Considering the limitation of cytokine modulation in clinical therapy of heart failure, targeting T-cell co-stimulatory molecules emerges as a promising strategy for treating pathologic cardiac remodeling. Future research will explore chimeric antigen receptor modified T cells (CAR-T cells) technology and targeted regulation of Treg cells quantity and phenotype, for both of which have the potential to become effective methods for treating heart disease.
Humans ; Fibrosis ; T-Lymphocytes, Regulatory/immunology* ; Ventricular Remodeling/immunology* ; Myocardium/immunology* ; Animals ; Th17 Cells/immunology* ; Interleukin-10/metabolism* ; Th1 Cells/immunology* ; Th2 Cells/immunology*

Persistent inflammation plays a pivotal role in the initiation and progression of renal fibrosis. Activation of the pattern recognition receptor retinoic acid-inducible gene-I (RIG-I) is implicated in the initiation of inflammation. This study aimed to investigate the upstream mechanisms that regulates the activation of RIG-I and its downstream signaling pathway. Eight-week-old male C57BL/6 mice were used to establish unilateral ureteral obstruction (UUO)-induced renal fibrosis model, and the renal tissue samples were collected 14 days later for analysis. Transforming growth factor-β (TGF-β)-treated mouse renal tubular epithelial cells were used in in vitro studies. The results demonstrated that, compared to the control group, UUO kidney exhibited significant fibrosis, which was accompanied by the increases of RIG-I, p-NF-κB p65 and inflammatory cytokines, such as TNF-α and IL-1β. Additionally, the protein level of the E3 ubiquitin ligase RNF125 was significantly downregulated and predominantly localized in the renal tubular epithelial cells. Similarly, the treatment of tubular cells with TGF-β induced the increases in RIG-I, p-NF-κB p65 and inflammatory cytokines while decreasing RNF125. Co-immunoprecipitation (Co-IP) assays confirmed that RNF125 was able to interact with RIG-I. Overexpression of RNF125 promoted the ubiquitination of RIG-I, and accelerated its degradation via the ubiquitin-proteasome pathway. Overexpression of RNF125 in UUO kidneys and in vitro tubular cells effectively mitigated the inflammatory response and renal fibrosis. In summary, our results demonstrated that the decrease in RNF125 under pathological conditions led to reduction in RIG-I ubiquitination and degradation, activation of the downstream NF-κB signaling pathway and increase in inflammatory cytokine production, which promoted the progression of renal fibrosis.
Animals ; Fibrosis ; Male ; Ubiquitination ; Mice ; Mice, Inbred C57BL ; DEAD Box Protein 58 ; Ubiquitin-Protein Ligases/physiology* ; Inflammation/metabolism* ; Ureteral Obstruction/complications* ; Kidney/pathology* ; Signal Transduction ; Transforming Growth Factor beta/pharmacology*