Lrba participates in the differentiation of IgA+ B lymphocytes through TGFßR signaling.

Introduction: Lrba is a cytoplasmic protein involved in vesicular trafficking. Lrba-deficient (Lrba-/-) mice exhibit substantially higher levels of IgA in both serum and feces than wild-type (WT) mice. Transforming growth factor ß1 (TGFß1) and its receptors (TGFßR I and II) is essential for differentiating IgA+ B cells. Furthermore, increased IgA production suggests a potential connection between Lrba and the TGFßR signaling pathway in IgA production. However, the specific function of Lrba in B cell biology remains unknown. Aim: Given the increased IgA levels in Lrba-/- mice, the goal in this work was to explore the lymph organs where the switch to IgA occurs, and if TGFßR function is affected. Methods: Non-immunized Lrba-/- mice were compared with Lrba+/+ mice. IgA levels in the serum and feces, as well as during peripheral B cell development, were determined. IgA+ B cells and plasma cells were assessed in the small intestine and secondary lymphoid organs, such as the spleen, mesenteric lymph nodes, and Peyer's patches. The TGFßR signaling pathway was evaluated by determining the expression of TGFßR on B cells. Additionally, SMAD2 phosphorylation was measured under basal conditions and in response to recombinant TGFß. Finally, confocal microscopy was performed to investigate a possible interaction between Lrba and TGFßR in B cells. Results: Lrba-/- mice exhibited significantly higher levels of circulating IgA, IgA+ B, and plasma cells than in peripheral lymphoid organs those in WT mice. TGFßR expression on the membrane of B cells was similar in both Lrba-/- and Lrba+/+ mice. However, intracellular TGFßR expression was reduced in Lrba-/- mice. SMAD2 phosphorylation showed increased levels under basal conditions; stimulation with recombinant TGFß elicited a poorer response than in that in Lrba+/+ B cells. Finally, we found that Lrba colocalizes with TGFßR in B cells. Conclusion: Lrba is essential in controlling TGFßR signaling, subsequently regulating SMAD2 phosphorylation on B cells. This mechanism may explain the increased differentiation of IgA+ B cells and production of IgA-producing plasma cells.

Repression of SMAD3 by STAT3 and c-Ski induces conventional dendritic cell differentiation.

A pleiotropic immunoregulatory cytokine, TGF-ß, signals via the receptor-regulated SMADs: SMAD2 and SMAD3, which are constitutively expressed in normal cells. Here, we show that selective repression of SMAD3 induces cDC differentiation from the CD115+ common DC progenitor (CDP). SMAD3 was expressed in haematopoietic cells including the macrophage DC progenitor. However, SMAD3 was specifically down-regulated in CD115+ CDPs, SiglecH- pre-DCs, and cDCs, whereas SMAD2 remained constitutive. SMAD3-deficient mice showed a significant increase in cDCs, SiglecH- pre-DCs, and CD115+ CDPs compared with the littermate control. SMAD3 repressed the mRNA expression of FLT3 and the cDC-related genes: IRF4 and ID2. We found that one of the SMAD transcriptional corepressors, c-SKI, cooperated with phosphorylated STAT3 at Y705 and S727 to repress the transcription of SMAD3 to induce cDC differentiation. These data indicate that STAT3 and c-Ski induce cDC differentiation by repressing SMAD3: the repressor of the cDC-related genes during the developmental stage between the macrophage DC progenitor and CD115+ CDP.

CKIP-1-Loaded Cartilage-Affinitive Nanoliposomes Reverse Osteoarthritis by Restoring Chondrocyte Homeostasis.

Osteoarthritis (OA) is a chronic joint disease characterized by cartilage imbalance and disruption of cartilage extracellular matrix secretion. Identifying key genes that regulate cartilage differentiation and developing effective therapeutic strategies to restore their expression is crucial. In a previous study, we observed a significant correlation between the expression of the gene encoding casein kinase-2 interacting protein-1 (CKIP-1) in the cartilage of OA patients and OA severity scores, suggesting its potential involvement in OA development. To test this hypothesis, we synthesized a chondrocyte affinity plasmid, liposomes CKIP-1, to enhance CKIP-1 expression in chondrocytes. Our results demonstrated that injection of CAP-Lipos-CKIP-1 plasmid significantly improved OA joint destruction and restored joint motor function by enhancing cartilage extracellular matrix (ECM) secretion. Histological and cytological analyses confirmed that CKIP-1 maintains altered the phosphorylation of the signal transduction molecule SMAD2/3 of the transforming growth factor-ß (TGF-ß) pathway by promoting the phosphorylation of the 8T, 416S sit. Taken together, this work highlights a novel approach for the precise modulation of chondrocyte phenotype from an inflammatory to a noninflammatory state for the treatment of OA and may be broadly applicable to patients suffering from other arthritic diseases.

MYH7 R453C induced cardiac remodelling via activating TGF-ß/Smad2/3, ERK1/2 and Nox4/ROS/NF-κB signalling pathways.

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-ß/Smad2/3, ERK1/2 and Nox4/ROS pathways have synergistic effects on cardiac remodelling and inflammation in MYH7 R453C mutation.

Marrow mesenchymal stem cell mediates diabetic nephropathy progression via modulation of Smad2/3/WTAP/m6A/ENO1 axis.

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-ß1 (TGF-ß1) 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.

Dang-Gui-Si-Ni decoction facilitates wound healing in diabetic foot ulcers by regulating expression of AGEs/RAGE/TGF-ß/Smad2/3.

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-ß/Smad2/3 expression by Western blot were performed. In vitro, intervention with LY2109761 (TGF-ß 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-ß/Smad2/3 expression by Western blot were measured. DFU rats exhibited elevated AGEs/RAGE expression, whereas decreased TGF-ß1 and p-Smad3/Smad3 protein expression, accompanied by higher IL-1ß, IL-6, TNF-α levels, and oxidative stress. DSD intervention reversed above effects. Glucose induction caused lower cell viability, migration, TGF-ß1 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-ß/Smad2/3, providing scientific experimental evidence for DSD clinical application for DFU therapy.

CircZfp644-205 inhibits osteoblast differentiation and induces apoptosis of pre-osteoblasts via sponging miR-455-3p and promoting SMAD2 expression.

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.

[Gene-gene/gene-environment interaction of transforming growth factor-ß signaling pathway and the risk of non-syndromic oral clefts].

OBJECTIVE: To explore the association between polymorphisms of transforming growth factor-ß (TGF-ß) 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-ß 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. CONCLUSION: The comprehensive evaluation of SNP associations and interactions within the TGF-ß 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-ß signaling pathway. These findings underscore the necessity for further investigations to unravel these results and further explore the underlying biological mechanisms.

[Tofacitinib inhibits the transformation of lung fibroblasts into myofibroblasts through JAK/STAT3 pathway].

OBJECTIVE: To investigate the effect of tofacitinib, a pan-Janus kinase (JAK) inhibitor, on transforming growth factor-beta 1 (TGF-ß1)-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-ß1 induction group, and TGF-ß1 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-ß1 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-ß1 induction. (2) The expression of α-SMA, COL1A1 and FN1 genes of HFL-1 in the TGF-ß1-induced groups was significantly up-regulated compared with the blank control group (P < 0.05). Compared with the TGF-ß1 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-ß1-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-ß1-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-ß1-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-ß1-induced group, the α-SMA protein level in the intervention groups with different concentrations decreased. And the differences between the TGF-ß1-induced group and 2.0 µmol/L or 5.0 µmol/L intervention groups were statistically significant (P < 0.05). Compared with the TGF-ß1-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-ß1-induced group. (4) After TGF-ß1 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-ß1-induced IL-6 gene expression and IL-6 in culture supernatant. TGF-ß1 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-ß1-induced Smad2/3 phosphorylation at 6 h and inhibited TGF-ß1-induced STAT3 phosphorylation at 1 h, 6 h and 24 h. CONCLUSION: Tofacitinib can inhibit the transformation of HFL-1 cells into myofibroblasts induced by TGF-ß1, and the mechanism may be through inhibiting the classic Smad2/3 pathway as well as the phosphorylation of STAT3 induced by TGF-ß1, thereby protecting the disease progression of pulmonary fibrosis.

[A recombinant adeno-associated virus expressing secretory TGF-ß type â ¡ receptor inhibits triple-negative murine breast cancer 4T1 cell proliferation and lung metastasis in mice].

OBJECTIVE: To investigate the effects of an adeno-associated virus (AAV2) vector expressing secretory transforming growth factor-ß (TGF-ß) type Ⅱ receptor (sTßRⅡ) extracellular domain-IgG2a Fc fusion protein (sTßRⅡ-Fc) on proliferation and migration of triple-negative murine breast cancer 4T1 cells in mice. METHODS: The pAAV-sTßRⅡ-Fc vector expressing sTßRⅡ-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-sTßRⅡ virus, which was purified by density gradient centrifugation with iodixanol. Western blotting was used to examine the effects of AAV-sTßRⅡ 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-sTßRⅡ 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 sTßRⅡ 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-sTßRⅡ-Fc vector successfully expressed sTßRⅡ in HEK 293T cells. Infection with AAV2-sTßRⅡ virus significantly reduced TGF-ß1-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-sTßRⅡ 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 sTßRⅡ expression without causing body weight loss or heart, liver, spleen or kidney pathologies. CONCLUSION: The recombinant AVV2 vector encoding sTßRⅡ extracellular domain is capable of blocking the TGF-ß signaling pathway to inhibit the proliferation and lung metastasis of 4T1 cells in mice.

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.

Introduction of miR-3613-3p as a regulator of transforming growth factor-ß (TGF-ß) signaling pathway in colorectal cancer.

INTRODUCTION: Colorectal cancer (CRC) is the second common cancer and the fourth major reason of cancer death worldwide. Dysregulation of intracellular pathways, such as TGF-ß/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-ß /SMAD signaling pathway in CRC. METHODS & 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-ßR1, TGF-ßR2, 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-ßR1 and TGF-ßR2 genes. Furthermore, reduced SMAD3 protein level following the miR-3613-3p overexpression verified its suppressive effect against TGF-ß 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. CONCLUSION: Our findings indicated that miR-3613-3p plays an important role in CRC by targeting the TGF-ß/SMAD signaling pathway and could be considered as a new candidate for further therapy investigations.

Neferine mitigates angiotensin II-induced atrial fibrillation and fibrosis via upregulation of Nrf2/HO-1 and inhibition of TGF-ß/p-Smad2/3 pathways.

BACKGROUND: Atrial fibrillation (AF) is often associated with atrial fibrosis and oxidative stress. Neferine, a bisbenzylisoquinoline alkaloid, has been reported to exert an antiarrhythmic effect. However, its impact on Angiotensin II (Ang II) infusion-induced AF and the underlying mechanism remains unclear. This study aimed to investigate whether neferine alleviates Ang II-induced AF and explore the underlying mechanisms. METHODS: Mice subjected to Ang II infusion to induce AF were concurrently treated with neferine or saline. AF incidence, myocardial cell size, fibrosis, and oxidative stress were then examined. RESULTS: Neferine treatment inhibited Ang II-induced AF, atrial size augmentation, and atrial fibrosis. Additionally, we observed that Ang II increased reactive oxygen species (ROS) generation, induced mitochondrial membrane potential depolarization, and reduced glutathione (GSH) and superoxide dismutase (SOD) levels, which were reversed to some extent by neferine. Mechanistically, neferine activated the Nrf2/HO-1 signaling pathway and inhibited TGF-ß/p-Smad2/3 in Ang II-infused atria. Zinc Protoporphyrin (ZnPP), an HO-1 inhibitor, reduced the anti-oxidative effect of neferine to some extent and subsequently abolished the beneficial effect of neferine on Ang II-induced AF. CONCLUSIONS: These findings provide hitherto undocumented evidence that the protective role of neferine in Ang II-induced AF is dependent on HO-1.

The Presence of TGFß3 in Human Ovarian Intrafollicular Fluid and Its Involvement in Thromboxane Generation in Follicular Granulosa Cells through a Canonical TGFßRI, Smad2/3 Signaling Pathway and COX-2 Induction.

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 ß (TGFß), TNF-α, and follicular granulosa cells (GCs) as possible contributors to FF TX production. Therefore, this study sought to investigate the role of TGFß3 in regulating TX generation in human ovarian follicular GCs. TGFß3 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, TGFß3 induced TX generation/secretion and the converting enzyme-COX-2 protein/mRNA expression both in human HO23 and primary cultured ovarian follicular GCs. While TGFßRI 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 TGFß3-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 TGFß3. Taken together, the results presented here first demonstrated that FF TGFß3 levels differ significantly in IVF patients' large preovulatory and small mid-antral follicles and are positively associated with oocyte maturation. TGFß3 can provoke TX generation by induction of COX-2 mRNA/protein via a TGFßR-related canonical Smad2/3 signaling pathway, and TX secretion possibly by ERK1/2. These imply that TGFß3 is one of the inducers for yielding FF TX in vivo, which may play a role in folliculogenesis and oocyte maturation.

Silica's silent threat: Contributing to skin fibrosis in systemic sclerosis by targeting the HDAC4/Smad2/3 pathway.

Nowadays, silica products are widely used in daily life, especially in skin applications, which inevitably increases the risk of silica exposure in general population. However, inadequate awareness of silica's potential hazards and lack of self-protection are of concern. Systemic sclerosis (SSc) is characterized by progressive tissue fibrosis under environmental and genetic interactions. Silica exposure is considered an important causative factor for SSc, but its pathogenesis remains unclear. Within this study, we showed that lower doses of silica significantly promoted the proliferation, migration, and activation of human skin fibroblasts (HSFs) within 24 h. Silica injected subcutaneously into mice induced and exacerbated skin fibrosis. Notably, silica increased histone deacetylase-4 (HDAC4) expression by inducing its DNA hypomethylation in normal HSFs. The elevated HDAC4 expression was also confirmed in SSc HSFs. Furthermore, HDAC4 was positively correlated with Smad2/3 phosphorylation and COL1, α-SMA, and CTGF expression. The HDAC4 inhibitor LMK235 mitigated silica-induced upregulation of these factors and alleviated skin fibrosis in SSc mice. Taken together, silica induces and exacerbates skin fibrosis in SSc patients by targeting the HDAC4/Smad2/3 pathway. Our findings provide new insights for evaluating the health hazards of silica exposure and identify HDAC4 as a potential interventional target for silica-induced SSc skin fibrosis.

Exosomal let-7a-5p derived from human umbilical cord mesenchymal stem cells alleviates coxsackievirus B3-induced cardiomyocyte ferroptosis via the SMAD2/ZFP36 signal axis. / 人脐带间å 质干细胞来源的外泌体let-7a-5p通过SMAD2/ZFP36ä¿¡å·è½´å‡è½»æŸ¯è¨å¥‡ç— æ¯’B3诱导的心肌细胞铁死亡.

Viral myocarditis (VMC) is one of the most common acquired heart diseases in children and teenagers. However, its pathogenesis is still unclear, and effective treatments are lacking. This study aimed to investigate the regulatory pathway by which exosomes alleviate ferroptosis in cardiomyocytes (CMCs) induced by coxsackievirus B3 (CVB3). CVB3 was utilized for inducing the VMC mouse model and cellular model. Cardiac echocardiography, left ventricular ejection fraction (LVEF), and left ventricular fractional shortening (LVFS) were implemented to assess the cardiac function. In CVB3-induced VMC mice, cardiac insufficiency was observed, as well as the altered levels of ferroptosis-related indicators (glutathione peroxidase 4 (GPX4), glutathione (GSH), and malondialdehyde (MDA)). However, exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs-exo) could restore the changes caused by CVB3 stimulation. Let-7a-5p was enriched in hucMSCs-exo, and the inhibitory effect of hucMSCs-exolet-7a-5p mimic on CVB3-induced ferroptosis was higher than that of hucMSCs-exomimic NC (NC: negative control). Mothers against decapentaplegic homolog 2 (SMAD2) increased in the VMC group, while the expression of zinc-finger protein 36 (ZFP36) decreased. Let-7a-5p was confirmed to interact with SMAD2 messenger RNA (mRNA), and the SMAD2 protein interacted directly with the ZFP36 protein. Silencing SMAD2 and overexpressing ZFP36 inhibited the expression of ferroptosis-related indicators. Meanwhile, the levels of GPX4, solute carrier family 7, member 11 (SLC7A11), and GSH were lower in the SMAD2 overexpression plasmid (oe-SMAD2)+let-7a-5p mimic group than in the oe-NC+let-7a-5p mimic group, while those of MDA, reactive oxygen species (ROS), and Fe2+ increased. In conclusion, these data showed that ferroptosis could be regulated by mediating SMAD2 expression. Exo-let-7a-5p derived from hucMSCs could mediate SMAD2 to promote the expression of ZFP36, which further inhibited the ferroptosis of CMCs to alleviate CVB3-induced VMC.

Verteporfin inhibits TGF-ß signaling by disrupting the Smad2/3-Smad4 interaction.

Transforming growth factor-ß (TGF-ß) signaling plays a crucial role in pathogenesis, such as accelerating tissue fibrosis and promoting tumor development at the later stages of tumorigenesis by promoting epithelial-mesenchymal transition (EMT), cancer cell migration, and invasion. Targeting TGF-ß signaling is a promising therapeutic approach, but nonspecific inhibition may result in adverse effects. In this study, we focus on the Smad2/3-Smad4 complex, a key component in TGF-ß signaling transduction, as a potential target for cancer therapy. Through a phase-separated condensate-aided biomolecular interaction system, we identified verteporfin (VP) as a small-molecule inhibitor that specifically targets the Smad2/3-Smad4 interaction. VP effectively disrupted the interaction between Smad2/3 and Smad4 and thereby inhibited canonical TGF-ß signaling, but not the interaction between Smad1 and Smad4 in bone morphogenetic protein (BMP) signaling. Furthermore, VP exhibited inhibitory effects on TGF-ß-induced EMT and cell migration. Our findings indicate a novel approach to develop protein-protein interaction inhibitors of the canonical TGF-ß signaling pathway for treatments of related diseases.

Liebig's law of the minimum in the TGF-ß/SMAD pathway.

Cells use signaling pathways to sense and respond to their environments. The transforming growth factor-ß (TGF-ß) pathway produces context-specific responses. Here, we combined modeling and experimental analysis to study the dependence of the output of the TGF-ß pathway on the abundance of signaling molecules in the pathway. We showed that the TGF-ß pathway processes the variation of TGF-ß receptor abundance using Liebig's law of the minimum, meaning that the output-modifying factor is the signaling protein that is most limited, to determine signaling responses across cell types and in single cells. We found that the abundance of either the type I (TGFBR1) or type II (TGFBR2) TGF-ß receptor determined the responses of cancer cell lines, such that the receptor with relatively low abundance dictates the response. Furthermore, nuclear SMAD2 signaling correlated with the abundance of TGF-ß receptor in single cells depending on the relative expression levels of TGFBR1 and TGFBR2. A similar control principle could govern the heterogeneity of signaling responses in other signaling pathways.

Renoprotective effect of rosmarinic acid by inhibition of indoxyl sulfate-induced renal interstitial fibrosis via the NLRP3 inflammasome signaling.

We previously reported that rosmarinic acid (RA) ameliorated renal fibrosis in a unilateral ureteral obstruction (UUO) murine model of chronic kidney disease. This study aimed to determine whether RA attenuates indoxyl sulfate (IS)-induced renal fibrosis by regulating the activation of the NLRP3 inflammasome/IL-1ß/Smad circuit. We discovered the NLRP3 inflammasome was activated in the IS treatment group and downregulated in the RA-treated group in a dose-dependent manner. Additionally, the downstream effectors of the NLRP3 inflammasome, cleaved-caspase-1 and cleaved-IL-1ß showed similar trends in different groups. Moreover, RA administration significantly decreased the ROS levels of reactive oxygen species in IS-treated cells. Our data showed that RA treatment significantly inhibited Smad-2/3 phosphorylation. Notably, the effects of RA on NLRP3 inflammasome/IL-1ß/Smad and fibrosis signaling were reversed by the siRNA-mediated knockdown of NLRP3 or caspase-1 in NRK-52E cells. In vivo, we demonstrated that expression levels of NLRP3, c-caspase-1, c-IL-1ß, collagen I, fibronectin and α-SMA, and TGF- ß 1 were downregulated after treatment of UUO mice with RA or RA + MCC950. Our findings suggested RA and MCC950 synergistically inhibited UUO-induced NLRP3 signaling activation, revealing their renoprotective properties and the potential for combinatory treatment of renal fibrosis and chronic kidney inflammation.

Vinpocetine alleviated alveolar epithelial cells injury in experimental pulmonary fibrosis by targeting PPAR-γ/NLRP3/NF-κB and TGF-ß1/Smad2/3 pathways.

This study aimed to investigate the potential anti-fibrotic activity of vinpocetine in an experimental model of pulmonary fibrosis by bleomycin and in the MRC-5 cell line. Pulmonary fibrosis was induced in BALB/c mice by oropharyngeal aspiration of a single dose of bleomycin (5 mg/kg). The remaining induced animals received a daily dose of pirfenidone (as a standard anti-fibrotic drug) (300 mg/kg/PO) and vinpocetine (20 mg/kg/PO) on day 7 of the induction till the end of the experiment (day 21). The results of the experiment revealed that vinpocetine managed to alleviate the fibrotic endpoints by statistically improving (P ≤ 0.05) the weight index, histopathological score, reduced expression of fibrotic-related proteins in immune-stained lung sections, as well as fibrotic markers measured in serum samples. It also alleviated tissue levels of oxidative stress and inflammatory and pro-fibrotic mediators significantly elevated in bleomycin-only induced animals (P ≤ 0.05). Vinpocetine managed to express a remarkable attenuating effect in pulmonary fibrosis both in vivo and in vitro either directly by interfering with the classical TGF-ß1/Smad2/3 signaling pathway or indirectly by upregulating the expression of Nrf2 enhancing the antioxidant system, activating PPAR-γ and downregulating the NLRP3/NF-κB pathway making it a candidate for further clinical investigation in cases of pulmonary fibrosis.