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-β1 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-β1 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-β, AKT, and ERK 1/2 expression levels. These outcomes underscore EP\'s antifibrotic potential, suggesting its viability as a therapeutic approach for keloids.

OBJECTIVE: To investigate the effect of tofacitinib, a pan-Janus kinase (JAK) inhibitor, on transforming growth factor-beta 1 (TGF-β1)-induced fibroblast to myofibroblast transition (FMT) and to explore its mechanism. To provide a theoretical basis for the clinical treatment of connective tissue disease-related interstitial lung disease (CTD-ILD).
METHODS: (1) Human fetal lung fibroblast 1 (HFL-1) were cultured in vitro, and 6 groups were established: DMSO blank control group, TGF-β1 induction group, and TGF-β1 with different concentrations of tofacitinib (0.5, 1.0, 2.0, 5.0 μmol/L) drug intervention experimental groups. CCK-8 was used to measure the cell viability, and wound-healing assay was performed to measure cell migration ability. After 48 h of combined treatment, quantitative real-time PCR (RT-PCR) and Western blotting were used to detect the gene and protein expression levels of α-smooth muscle actin (α-SMA), fibronectin (FN), and collagen type Ⅰ (COL1). (2) RT-PCR and enzyme-linked immunosorbnent assay (ELISA) were used to detect the interleukin-6 (IL-6) gene and protein expression changes, respectively. (3) DMSO carrier controls, 1.0 μmol/L and 5.0 μmol/L tofacitinib were added to the cell culture media of different groups for pre-incubation for 30 min, and then TGF-β1 was added to treat for 1 h, 6 h and 24 h. The phosphorylation levels of Smad2/3 and signal transducer and activator of transcription 3 (STAT3) protein were detected by Western blotting.
RESULTS: (1) Tofacitinib inhibited the viability and migration ability of HFL-1 cells after TGF-β1 induction. (2) The expression of α-SMA, COL1A1 and FN1 genes of HFL-1 in the TGF-β1-induced groups was significantly up-regulated compared with the blank control group (P < 0.05). Compared with the TGF-β1 induction group, α-SMA expression in the 5.0 μmol/L tofacitinib intervention group was significantly inhi-bited (P < 0.05). Compared with the TGF-β1-induced group, FN1 gene was significantly inhibited in each intervention group at a concentration of 0.5-5.0 μmol/L (P < 0.05). Compared with the TGF-β1-induced group, the COL1A1 gene expression in each intervention group did not change significantly. (3) Western blotting results showed that the protein levels of α-SMA and FN1 in the TGF-β1-induced group were significantly higher than those in the control group (P < 0.05), and there was no significant difference in the expression of COL1A1. Compared with the TGF-β1-induced group, the α-SMA protein level in the intervention groups with different concentrations decreased. And the differences between the TGF-β1-induced group and 2.0 μmol/L or 5.0 μmol/L intervention groups were statistically significant (P < 0.05). Compared with the TGF-β1-induced group, the FN1 protein levels in the intervention groups with different concentrations showed a downward trend, but the difference was not statistically significant. There was no difference in COL1A1 protein expression between the intervention groups compared with the TGF-β1-induced group. (4) After TGF-β1 acted on HFL-1 cells for 48 h, the gene expression of the IL-6 was up-regulated and IL-6 in culture supernatant was increased, the intervention with tofacitinib partly inhibited the TGF-β1-induced IL-6 gene expression and IL-6 in culture supernatant. TGF-β1 induced the increase of Smad2/3 protein phosphorylation in HFL-1 cells for 1 h and 6 h, STAT3 protein phosphorylation increased at 1 h, 6 h and 24 h, the pre-intervention with tofacitinib inhibited the TGF-β1-induced Smad2/3 phosphorylation at 6 h and inhibited TGF-β1-induced STAT3 phosphorylation at 1 h, 6 h and 24 h.
CONCLUSIONS: Tofacitinib can inhibit the transformation of HFL-1 cells into myofibroblasts induced by TGF-β1, and the mechanism may be through inhibiting the classic Smad2/3 pathway as well as the phosphorylation of STAT3 induced by TGF-β1, thereby protecting the disease progression of pulmonary fibrosis.

OBJECTIVE: To explore the association between polymorphisms of transforming growth factor-β (TGF-β) signaling pathway and non-syndromic cleft lip with or without cleft palate (NSCL/P) among Asian populations, while considering gene-gene interaction and gene-environment interaction.
METHODS: A total of 1 038 Asian NSCL/P case-parent trios were ascertained from an international consortium, which conducted a genome-wide association study using a case-parent trio design to investigate the genes affec-ting risk to NSCL/P. After stringent quality control measures, 343 single nucleotide polymorphism (SNP) spanning across 10 pivotal genes in the TGF-β signaling pathway were selected from the original genome-wide association study(GWAS) dataset for further analysis. The transmission disequilibrium test (TDT) was used to test for SNP effects. The conditional Logistic regression models were used to test for gene-gene interaction and gene-environment interaction. Environmental factors collected for the study included smoking during pregnancy, passive smoking during pregnancy, alcohol intake during pregnancy, and vitamin use during pregnancy. Due to the low rates of exposure to smoking during pregnancy and alcohol consumption during pregnancy (<3%), only the interaction between maternal smoking during pregnancy and multivitamin supplementation during pregnancy was analyzed. The threshold for statistical significance was rigorously set at P =1.46×10-4, applying Bonferroni correction to account for multiple testing.
RESULTS: A total of 23 SNPs in 4 genes yielded nominal association with NSCL/P (P<0.05), but none of these associations was statistically significant after Bonferroni\' s multiple test correction. However, there were 6 pairs of SNPs rs4939874 (SMAD2) and rs1864615 (TGFBR2), rs2796813 (TGFB2) and rs2132298 (TGFBR2), rs4147358 (SMAD3) and rs1346907 (TGFBR2), rs4939874 (SMAD2) and rs1019855 (TGFBR2), rs4939874 (SMAD2) and rs12490466 (TGFBR2), rs2009112 (TGFB2) and rs4075748 (TGFBR2) showed statistically significant SNP-SNP interaction (P<1.46×10-4). In contrast, the analysis of gene-environment interactions did not yield any significant results after being corrected by multiple testing.
CONCLUSIONS: The comprehensive evaluation of SNP associations and interactions within the TGF-β signaling pathway did not yield any direct associations with NSCL/P risk in Asian populations. However, the significant gene-gene interactions identified suggest that the genetic architecture influencing NSCL/P risk may involve interactions between genes within the TGF-β signaling pathway. These findings underscore the necessity for further investigations to unravel these results and further explore the underlying biological mechanisms.

OBJECTIVE: To investigate the effects of an adeno-associated virus (AAV2) vector expressing secretory transforming growth factor-β (TGF-β) type Ⅱ receptor (sTβRⅡ) extracellular domain-IgG2a Fc fusion protein (sTβRⅡ-Fc) on proliferation and migration of triple-negative murine breast cancer 4T1 cells in mice.
METHODS: The pAAV-sTβRⅡ-Fc vector expressing sTβRⅡ-Fc fusion protein constructed by molecular cloning, the capsid protein-expressing vector pAAV2 and the helper vector were co-transfected into HEK 293T cells to prepare the recombinant AAV2-sTβRⅡ virus, which was purified by density gradient centrifugation with iodixanol. Western blotting was used to examine the effects of AAV-sTβRⅡ virus on Smad2/3 phosphorylation in 4T1 cells and on expression levels of E-cadherin, vimentin and p-Smad2/3 in 4T1 cell xenografts in mice. BALB/c mice bearing subcutaneous xenografts of luciferase-expressing 4T1 cells received intravenous injections of AAV-sTβRⅡ virus, AAV-GFP virus or PBS (n=6) through the tail vein, and the proliferation and migration of 4T1 cells were analyzed with in vivo imaging. Ki67 expression in the tumor tissues and sTβRⅡ protein expressions in mouse livers were detected with immunohistochemistry and immunofluorescence staining, and tumor metastases in the vital organs were examined with HE staining.
RESULTS: The recombinant pAAV-sTβRⅡ-Fc vector successfully expressed sTβRⅡ in HEK 293T cells. Infection with AAV2-sTβRⅡ virus significantly reduced TGF-β1-induced Smad2/3 phosphorylation in 4T1 cells and effectively inhibited proliferation and lung metastasis of 4T1 xenografts in mice (P<0.05). In the tumor-bearing mice, intravenous injection of AAV-sTβRⅡ virus significantly increased E-cadherin expression, reduced vimentin and Ki67 protein expressions and Smad2/3 phosphorylation level in the tumor tissues (P<0.05 or 0.01), and induced liver-specific sTβRⅡ expression without causing body weight loss or heart, liver, spleen or kidney pathologies.
CONCLUSIONS: The recombinant AVV2 vector encoding sTβRⅡ extracellular domain is capable of blocking the TGF-β signaling pathway to inhibit the proliferation and lung metastasis of 4T1 cells in mice.

Hypertrophic cardiomyopathy (HCM) is a monogenic cardiac disorder commonly induced by sarcomere gene mutations. However, the mechanism for HCM is not well defined. Here, we generated transgenic MYH7 R453C and MYH6 R453C piglets and found both developed typical cardiac hypertrophy. Unexpectedly, we found serious fibrosis and cardiomyocyte loss in the ventricular of MYH7 R453C, not MYH6 R453C piglets, similar to HCM patients. Then, RNA-seq analysis and western blotting identified the activation of ERK1/2 and PI3K-Akt pathways in MYH7 R453C. Moreover, we observed an increased expression of fetal genes and an excess of reactive oxygen species (ROS) in MYH7 R453C piglet models, which was produced by Nox4 and subsequently induced inflammatory response. Additionally, the phosphorylation levels of Smad2/3, ERK1/2 and NF-kB p65 proteins were elevated in cardiomyocytes with the MYH7 R453C mutation. Furthermore, epigallocatechin gallate, a natural bioactive compound, could be used as a drug to reduce cell death by adjusting significant downregulation of the protein expression of Bax and upregulated Bcl-2 levels in the H9C2 models with MYH7 R453C mutation. In conclusion, our study illustrated that TGF-β/Smad2/3, ERK1/2 and Nox4/ROS pathways have synergistic effects on cardiac remodelling and inflammation in MYH7 R453C mutation.

BACKGROUND: Colorectal cancer (CRC) is the second common cancer and the fourth major reason of cancer death worldwide. Dysregulation of intracellular pathways, such as TGF-β/SMAD signaling, contributes to CRC development. MicroRNAs (miRNAs) are post-transcriptional regulators that are involved in CRC pathogenesis. Here, we aimed to investigate the effect of miR-3613-3p on the TGF-β /SMAD signaling pathway in CRC.
RESULTS: Bioinformatics analysis suggested that miR-3613-3p is a regulator of TGF-Β signaling downstream genes. Then, miR-3613-3p overexpression was followed by downregulation of TGF-βR1, TGF-βR2, and SMAD2 expression levels, detected by RT-qPCR. Additionally, dual luciferase assay supported the direct interaction of miR-3613-3p with 3\'UTR sequences of TGF-βR1 and TGF-βR2 genes. Furthermore, reduced SMAD3 protein level following the miR-3613-3p overexpression verified its suppressive effect against TGF-β signaling in HCT-116 cells, detected by western blot analysis. Finally, miR-3613-3p overexpression induced sub-G1 arrest in HCT116 cells, detected by flow cytometry, and promoted downregulation of cyclin D1 protein expression, which was detected by western blotting analysis.
CONCLUSIONS: Our findings indicated that miR-3613-3p plays an important role in CRC by targeting the TGF-β/SMAD signaling pathway and could be considered as a new candidate for further therapy investigations.

BACKGROUND: Circular RNAs (circRNAs) are involved in the progression of osteoporosis; however, their impact on osteogenic differentiation has yet to be fully elucidated. In this study, we identified a novel circRNA known as circZfp644-205 and investigated its effect on osteogenic differentiation and apoptosis in osteoporosis.
METHODS: CircZfp644-205, miR-445-3p, and SMAD2 levels were measured using quantitative real-time polymerase chain reaction (qRT-PCR). MC3T3-E1 cells were subjected to microgravity (MG) to establish a cell model. Osteogenic differentiation was assessed using qRT-PCR, Alizarin Red S staining, alkaline phosphatase staining, and western blot. The apoptosis was evaluated using flow cytometry. The relationship between miR-445-3p and circZfp644-205 or SMAD2 was determined using bioinformatics, RNA pull-down, and luciferase reporter assay. Moreover, a hindlimb unloading mouse model was generated to investigate the role of circZfp644-205 in vivo using Micro-CT.
RESULTS: CircZfp644-205 expression was up-regulated significantly in HG-treated MC3T3-E1 cells. Further in vitro studies confirmed that circZfp644-205 knockdown inhibited the osteogenic differentiation and induced apoptosis of pre-osteoblasts. CircZfp644-205 acted as a sponge for miR-455-3p, which reversed the effects of circZfp644-205 on pre-osteoblasts. Moreover, miR-455-3p directly targeted SMAD2, thus inhibiting the expression of SMAD2 to regulate cellular behaviors. Moreover, circZfp644-205 alleviated the progression of osteoporosis in mice.
CONCLUSIONS: This study provides a novel circRNA that may serve as a potential therapeutic target for osteoporosis and expands our understanding of the molecular mechanism underlying the progression of osteoporosis.

Diabetic foot ulcer (DFU) is a predominant complication of diabetes mellitus with poor prognosis accompanied by high amputation and mortality rates. Dang-Gui-Si-Ni decoction (DSD), as a classic formula with a long history in China, has been found to improve DFU symptoms. However, mechanism of DSD for DFU therapy remains unclear with no systematic elaboration. In vivo, following establishment of DFU rat model, DSD intervention with low, medium and high doses was done, with Metformin (DM) as a positive control group. With wound healing detection, pathological changes by HE staining, inflammatory factor expression by ELISA and qRT-PCR, oxidative stress levels by ELISA, and AGEs/RAGE/TGF-β/Smad2/3 expression by Western blot were performed. In vitro, intervention with LY2109761 (TGF-β pathway inhibitor) based on DSD treatment in human dermal fibroblast-adult (HDF-a) cells was made. Cell viability by CCK8, migration ability by cell scratch, apoptosis by flow cytometry, and AGEs/RAGE/TGF-β/Smad2/3 expression by Western blot were measured. DFU rats exhibited elevated AGEs/RAGE expression, whereas decreased TGF-β1 and p-Smad3/Smad3 protein expression, accompanied by higher IL-1β, IL-6, TNF-α levels, and oxidative stress. DSD intervention reversed above effects. Glucose induction caused lower cell viability, migration, TGF-β1 and p-Smad3/Smad3 protein expression, with increased apoptosis and AGEs/RAGE expression in HDF-a cells. These effects were reversed after DSD intervention, and further LY2109761 intervention inhibited DSD effects in cells. DSD intervention may facilitate wound healing in DFU by regulating expression of AGEs/RAGE/TGF-β/Smad2/3, providing scientific experimental evidence for DSD clinical application for DFU therapy.

Diabetic nephropathy (DN) is one of the common microvascular complications in diabetic patients. Marrow mesenchymal stem cells (MSCs) have attracted attention in DN therapy but the underlying mechanism remains unclear. Here, we show that MSC administration alleviates high glucose (HG)-induced human kidney tubular epithelial cell (HK-2 cell) injury and ameliorates renal injury in DN mice. We identify that Smad2/3 is responsible for MSCs-regulated DN progression. The activity of Smad2/3 was predominantly upregulated in HG-induced HK-2 cell and DN mice and suppressed with MSC administration. Activation of Smad2/3 via transforming growth factor-β1 (TGF-β1) administration abrogates the protective effect of MSCs on HG-induced HK-2 cell injury and renal injury of DN mice. Smad2/3 has been reported to interact with methyltransferase of N6-methyladenosine (m6A) complex and we found a methyltransferase, Wilms\' tumor 1-associating protein (WTAP), is involved in MSCs-Smad2/3-regulated DN development. Moreover, WTAP overexpression abrogates the improvement of MSCs on HG-induced HK-2 cell injury and renal injury of DN mice. Subsequently, α-enolase (ENO1) is the downstream target of WTAP-mediated m6A modification and contributes to the MSCs-mediated regulation. Collectively, these findings reveal a molecular mechanism in DN progression and indicate that Smad2/3/WTAP/ENO1 may present a target for MSCs-mediated DN therapy.

Ovarian follicular fluid (FF) has a direct impact on oocyte quality, playing key roles in fertilization, implantation, and early embryo development. In our recent study, we found FF thromboxane (TX) to be a novel factor inversely correlated with oocyte maturation and identified thrombin, transforming growth factor β (TGFβ), TNF-α, and follicular granulosa cells (GCs) as possible contributors to FF TX production. Therefore, this study sought to investigate the role of TGFβ3 in regulating TX generation in human ovarian follicular GCs. TGFβ3 was differentially and significantly present in the FF of large and small follicles obtained from IVF patients with average concentrations of 68.58 ± 12.38 and 112.55 ± 14.82 pg/mL, respectively, and its levels were correlated with oocyte maturity. In an in vitro study, TGFβ3 induced TX generation/secretion and the converting enzyme-COX-2 protein/mRNA expression both in human HO23 and primary cultured ovarian follicular GCs. While TGFβRI and Smad2/3 signaling was mainly required for COX-2 induction, ERK1/2 appeared to regulate TX secretion. The participation of Smad2/3 and COX-2 in TGFβ3-induced TX generation/secretion could be further supported by the observations that Smad2/3 phosphorylation and nuclear translocation and siRNA knockdown of COX-2 expression compromised TX secretion in GCs challenged with TGFβ3. Taken together, the results presented here first demonstrated that FF TGFβ3 levels differ significantly in IVF patients\' large preovulatory and small mid-antral follicles and are positively associated with oocyte maturation. TGFβ3 can provoke TX generation by induction of COX-2 mRNA/protein via a TGFβR-related canonical Smad2/3 signaling pathway, and TX secretion possibly by ERK1/2. These imply that TGFβ3 is one of the inducers for yielding FF TX in vivo, which may play a role in folliculogenesis and oocyte maturation.