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While it is widely thought that de novo mutations (DNMs) occur randomly, we previously showed that some DNMs are enriched because they are positively selected in the testes of aging men. These "selfish" mutations cause disorders with a shared presentation of features, including exclusive paternal origin, significant increase of the father's age, and high apparent germline mutation rate. To date, all known selfish mutations cluster within the components of the RTK-RAS-MAPK signaling pathway, a critical modulator of testicular homeostasis. Here, we demonstrate the selfish nature of the SMAD4 DNMs causing Myhre syndrome (MYHRS). By analyzing 16 informative trios, we show that MYHRS-causing DNMs originated on the paternally derived allele in all cases. We document a statistically significant epidemiological paternal age effect of 6.3 years excess for fathers of MYHRS probands. We developed an ultra-sensitive assay to quantify spontaneous MYHRS-causing SMAD4 variants in sperm and show that pathogenic variants at codon 500 are found at elevated level in sperm of most men and exhibit a strong positive correlation with donor's age, indicative of a high apparent germline mutation rate. Finally, we performed in vitro assays to validate the peculiar functional behavior of the clonally selected DNMs and explored the basis of the pathophysiology of the different SMAD4 sperm-enriched variants. Taken together, these data provide compelling evidence that SMAD4 , a gene operating outside the canonical RAS-MAPK signaling pathway, is associated with selfish spermatogonial selection and raises the possibility that other genes/pathways are under positive selection in the aging human testis. Activating RAS-MAPK mutations occurring spontaneously in human spermatogonia cause clonal expansion of these stem cells with age, explaining the high birth prevalence of the associated disorders. We show that Myhre syndrome-causing mutations in SMAD4 , a gene operating outside the canonical RAS-MAPK signaling pathway, are positively selected in the male germline. [ABSTRACT FROM AUTHOR]

Activin A and hepatic stellate cells (HSCs) are involved in tissue repair and fibrosis in liver injury. This study investigated the impact of activin A on HSC activation and migration. A microfluidic D4-chip was used for examining the cell migration of mouse hepatic stellate cell line MHSteC. The analysis of differentially expressed genes revealed that activin βA (Inhba), activin receptor type 1A (Acvr1a) and type 2A (Acvr2a) mRNAs were more significantly expressed in human HSCs than in the hepatocytes. Moreover, activin A promoted MHSteC proliferation and induced MHSteC migration. Furthermore, the MHSteCs treated with activin A exhibited increased levels of migration-related proteins, N-cadherin, Vimentin, α-SMA, MMP2 and MMP9, but a decreased level of E-cadherin. Additionally, activin A treatment significantly increased the p-Smad3 levels and p-Smad3/Smad3 ratio in the MHSteCs, and the Smad3 inhibitor SIS3 attenuated activin A-induced MHSteC proliferation and migration. Simultaneously, activin A increased the calcium levels in the MHSteCs, and the migratory effects of activin A on MHSteCs were weakened by the intracellular calcium ion-chelating agent BAPTA-AM. These data indicate that activin A can promote MHSteC activation and migration through the canonical Smad3 signaling and calcium signaling. [ABSTRACT FROM AUTHOR]

Background: Epidermal remodeling and hypertrophy are hallmarks of skin fibrotic disorders, and keratinocyte to mesenchymal (EMT)-like transformations drive epidermis alteration in skin fibrosis such as keloids and hypertrophic scars (HTS). While phosphodiesterase 4 (PDE4) inhibitors have shown effectiveness in various fibrotic disorders, their role in skin fibrosis is not fully understood. This study aimed to explore the specific role of PDE4B in epidermal remodeling and hypertrophy seen in skin fibrosis. Methods: In vitro experiments examined the effects of inhibiting PDE4A-D (with Roflumilast) or PDE4B (with siRNA) on TGFβ1-induced EMT differentiation and dedifferentiation in human 3D epidermis. In vivo studies investigated the impact of PDE4 inhibition on HOCl-induced skin fibrosis and epidermal hypertrophy in mice, employing both preventive and therapeutic approaches. Results: The study found increased levels of PDE4B (mRNA, protein) in keloids > HTS compared to healthy epidermis, as well as in TGFβ-stimulated 3D epidermis. Keloids and HTS epidermis exhibited elevated levels of collagen Iα1, fibronectin, αSMA, N-cadherin, and NOX4 mRNA, along with decreased levels of E-cadherin and ZO-1, confirming an EMT process. Inhibition of both PDE4A-D and PDE4B prevented TGFβ1-induced Smad3 and ERK1/2 phosphorylation and mesenchymal differentiation in vitro. PDE4A-D inhibition also promoted mesenchymal dedifferentiation and reduced TGFβ1-induced ROS and keratinocyte senescence by rescuing PPM1A, a Smad3 phosphatase. In vivo, PDE4 inhibition mitigated HOCl-induced epidermal hypertrophy in mice in both preventive and therapeutic settings. Conclusions: Overall, the study supports the potential of PDE4 inhibitors, particularly PDE4B, in treating skin fibrosis, including keloids and HTS, shedding light on their functional role in this condition. [ABSTRACT FROM AUTHOR]

We previously reported pulmonary arterial remodelling and active endothelial-to-mesenchymal transition (EndMT) in smokers and patients with early chronic obstructive pulmonary disease (COPD). In the present study, we aimed to evaluate the role of different drivers of EndMT. Immunohistochemical staining for EndMT drivers, TGF-β1, pSMAD-2/3, SMAD-7, and β-catenin, was performed on lung resections from 46 subjects. Twelve were non-smoker-controls (NC), six normal lung function smokers (NLFS), nine patients with small-airway diseases (SAD), nine mild-moderate COPD-current smokers (COPD-CS) and ten COPD-ex-smokers (COPD-ES). Histopathological measurements were done using Image ProPlus softwarev7.0. We observed lower levels of total TGF-β1 (P<0.05) in all smoking groups than in the non-smoking control (NC). Across arterial sizes, smoking groups exhibited significantly higher (P<0.05) total and individual layer pSMAD-2/3 and SMAD-7 than in the NC group. The ratio of SAMD-7 to pSMAD-2/3 was higher in COPD patients compared with NC. Total β-catenin expression was significantly higher in smoking groups across arterial sizes (P<0.05), except for COPD-ES and NLFS groups in small and medium arteries, respectively. Increased total β-catenin was positively correlated with total S100A4 in small and medium arteries (r = 0.35, 0.50; P=0.02, 0.01, respectively), with Vimentin in medium arteries (r = 0.42, P=0.07), and with arterial thickness of medium and large arteries (r = 0.34, 0.41, P=0.02, 0.01, respectively). This is the first study uncovering active endothelial SMAD pathway independent of TGF-β1 in smokers, SAD, and COPD patients. Increased expression of β-catenin indicates its potential interaction with SMAD pathway, warranting further research to identify the deviation of this classical pathway [ABSTRACT FROM AUTHOR]

Here, we examined the effects of the BMP signaling pathway inhibitor LDN-193189 on the pluripotency of porcine embryonic stem cells (ESCs) in the absence of feeder cells using molecular and transcriptomic techniques. Additionally, the effects of some extracellular matrix components on porcine ESC pluripotency were evaluated to develop an optimized and sustainable feeder-free culture system for porcine ESCs. Feeder cells were found to play an important role in supporting the pluripotency of porcine ESCs by blocking trophoblast and mesodermal differentiation through the inhibition of the BMP pathway. Additionally, treatment with LDN-193189, an inhibitor of the BMP pathway, maintained the pluripotency and homogeneity of porcine ESCs for an extended period in the absence of feeder cells by stimulating the secretion of chemokines and suppressing differentiation, based on transcriptome analysis. Conclusively, these results suggest that LDN-193189 could be a suitable replacement for feeder cells in the maintenance of porcine ESC pluripotency during culture. Additionally, these findings contribute to the understanding of pluripotency gene networks and comparative embryogenesis. [Display omitted] • Inhibiting the SMAD signaling supports the stemness of pig ESCs without feeder cells. • LDN-193189 enhances the pig pluripotency by suppressing mesodermal differentiation. • These conditions enhance the stemness of pig ESCs, even in FBS-contained conditions. • The culture conditions ensure consistency and reproducibility of pig ESC cultures. [ABSTRACT FROM AUTHOR]

Objective(s): Liver fibrosis is a wound healing response characterized by excessive accumulation of extracellular matrix proteins. This study aimed to investigate the effects of resveratrol treatment on the TGF-β/SMAD signaling pathway and related biochemical parameters, apoptosis, and liver regeneration phenobarbital-CCl4 induced hepatic fibrosis rat model. Materials and Methods: This model was created through phenobarbital and CCl4 (0.2–0.35 ml/kg). Resveratrol (1 mg/kg/day) was administered to the fibrosis and control groups. Immunohistochemical staining was performed to evaluate αSMA, TGF-β1, and PCNA in liver tissue. The TUNEL method and Masson’s Trichome staining were used to determine apoptosis and collagen accumulation. AST, ALP, ALT, total protein, and total bilirubin levels were measured to determine biochemical status. SMAD2, SMAD3, SMAD4, and SMAD7 expression levels were measured to determine TGF-β1 related hepatic fibrosis. Results: The SMAD2, SMAD3, and SMAD4 mRNA expression levels were increased and the SMAD7 mRNA expression level was decreased in the fibrosis control group. The SMAD7 mRNA expression level was higher in the phenobarbital-CCl4 induced resveratrol treated group. Increased biochemical parameters indicating hepatic damage, increased number of apoptotic cells, and collagen accumulation surrounding the central vein were observed in the fibrosis group compared with the other groups. It was concluded that administration of resveratrol ameliorates the adverse effects of hepatic fibrosis by regulating biochemical parameters, controlling TGF-β1/SMAD signaling, enhancing tissue regeneration, and reducing apoptosis in liver cells. Conclusion: Resveratrol can be a beneficial option for the prevention of liver damage in a phenobarbital-CCl4 induced hepatic fibrosis. [ABSTRACT FROM AUTHOR]

The present study aimed to elucidate the pathogenesis of temporomandibular joint (TMJ) osteoarthritis (TMJ-OA) in a mouse model. We investigated morphological and histological changes in the head of mandible cartilage and early immunohistochemical (IHC) changes in transforming growth factor (TGF)-β, phosphorylated Smad-2/3 (p-Smad2/3), a TGF-β signaling molecule, and asporin. TMJ-OA was induced in a mouse model through unilateral partial discectomy. Micro-computed tomography (micro-CT) and safranin-O staining were performed to morphologically and histologically evaluate the degeneration of the head of mandible caused by TMJ-OA. IHC staining for TGF-β, p-Smad2/3, and asporin was performed to evaluate the changes in protein expression. In the experimental group, three-dimensional (3D) morphometry revealed an enlarged head of mandible and safranin-O staining showed degeneration of cartilage tissue in the early stages of TMJ-OA compared to the control group. IHC staining revealed that TGF-β, p-Smad2/3, and asporin expression increased in the head of mandible cartilage before the degeneration of cartilage tissue, and subsequently decreased for a short period. The findings suggested a negative feedback relationship between the expression of asporin and the TGF-β/Smad transduction pathway, which may be involved in the degeneration of the head of mandible in the early stages of TMJ-OA. Asporin is a potential biomarker of the early stages of TMJ-OA, which ultimately leads to the irreversible degeneration of TMJ tissues. [ABSTRACT FROM AUTHOR]

SMAD4 is a tumor suppressor mutated or silenced in multiple cancers, including oral cavity squamous cell carcinoma (OSCC). Human clinical samples and cell lines, mouse models and organoid culture were used to investigate the role that SMAD4 plays in progression from benign disease to invasive OSCC. Human OSCC lost detectable SMAD4 protein within tumor epithelium in 24% of cases, and this loss correlated with worse progression‐free survival independent of other major clinical and pathological features. A mouse model engineered for KrasG12D expression in the adult oral epithelium induced benign papillomas, however the combination of KrasG12D with loss of epithelial Smad4 expression resulted in rapid development of invasive carcinoma with features of human OSCC. Examination of regulatory pathways in 3D organoid cultures of SMAD4+ and SMAD4− mouse tumors with Kras mutation found that either loss of SMAD4 or inhibition of TGFβ signaling upregulated the WNT pathway and altered the extracellular matrix. The gene signature of the mouse tumor organoids lacking SMAD4 was highly similar to the gene signature of human head and neck squamous cell carcinoma. In summary, this work has uncovered novel mechanisms by which SMAD4 acts as a tumor suppressor in OSCC. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

Colorectal cancer is one of the most common cancers around the world, which is a severe threat to people's health. SMAD4 belongs to the dwarfin/SMAD family, which plays a crucial role in TGF-β and BMP signal pathways. As the molecular characterization of colon cancer patients following SMAD4 mutations remains unclear, we integrated multi-omics data of SMAD4 mutant patients to reveal the profile of molecular characterization of SMAD4 mutation. A missense mutation is the most common mutant type of SMAD4. Patients with SMAD4 mutation had worse survival. Tumor tissues from patients carrying the SMAD4 mutation showed a reduction in various immune cells, such as CD4 + memory T cells and memory B cells. Many differential genes were identified compared to the SMAD4 mutation-free group and could be significantly enriched for tumor- and immune-related signaling pathways. In addition, the mutant group had different drug sensitivities than the non-mutant group. [ABSTRACT FROM AUTHOR]

Background: Pulmonary hypertension (PH) is a long-term disease that impacts approximately 1% of the world's population. Currently, levosimendan (Lev) is proposed for PH treatment. However, the mechanism of Lev in the treatment of PH is unknown. Methods: We used hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) to establish a PH cell model. A number of cell biology methods were performed to assay alterations in cell proliferation, migration and apoptosis after Lev treatment. qRT-PCR and WB were performed to test the levels of circUSP34 and miR-1298, and BMP/Smad protein respectively. In addition, the regulatory relationship between circUSP34 or BMPR2 with miR-1298 was verified through the use of double luciferase as well as RIP assay. In addition, we explored the regulatory effect of Lev on the circUSP34/miR-1298/BMP/Smad axis using a rat PH model. Results: Our results demonstrate that Lev inhibited PASMCs cell proliferation, migration and promoted apoptosis exposed to hypoxia. In hypoxia-treated PASMCs, circUSP34 expression got downregulated while miR-1298 upregulated, whereas the addition with Lev resulted in upregulation of circUSP34 expression and downregulation of miR-1298 expression, indicating that circUSP34 can target and regulate miR-1298. In addition, miR-1298 targets and regulates the expression of BMPR2. In a rat PH model induced by hypoxia combined with SU5416, Lev upregulated circUSP34 targeting miR-1298-mediated BMP/Smad axis to alleviate the PH phenotype. Conclusion: We have shown that Lev can be used as a therapeutic drug for PH patients, which works through the circUSP34/miR-1298/BMP/Smad axis to alleviate PH symptoms. [ABSTRACT FROM AUTHOR]

This study aimed to determine the function of angiopoietin-related protein 4 (ANGPTL4) and bone morphogenetic protein 7 (BMP7) on hepatocellular carcinoma (HCC). Overexpressing plasmids were cotransfected into HepG2 cells to determine the interaction between ANGPTL4 and BMP7. The effect of ANGPTL4 on the stability of BMP7 is examined by detecting the expression and ubiquitination levels. In vitro and in vivo experiments of knocking down ANGPTL4 while overexpressing BMP7 were performed to investigate whether the effects of ANGPTL4 on HCC proliferation, migration, and downstream signaling pathways were dependent on BMP7. ANGPTL4 is able to interact with BMP7, and knockdown of ANGPTL4 increased BMP7 expression and ubiquitination. Overexpression of BMP7 reversed the inhibition of HCC proliferation and migration as well as the decrease in the expression levels of Smad1/5/8 and MAPK14 caused by knockdown of ANGPTL4. ANGPTL4 promotes the proliferation and migration of HCC by inhibiting the ubiquitination degradation of BMP7 and the Smad/MAPK pathway, providing a novel mechanism and a potential therapeutic target for the treatment of HCC. [ABSTRACT FROM AUTHOR]

Myosin Va (Myo Va) is one of three protein complexes involved in melanosome transport. In this study, we identified BMP-2 as an up-regulator of Myo Va expression using 2-methyl-naphtho[1,2,3-de]quinolin-8-one (MNQO). Our results showed that MNQO reduced the mRNA and protein expression of Myo Va and BMP-2 in melanocytes. Knockdown of BMP-2 by siRNA also affected Myo Va mRNA and protein expression, confirming that MNQO regulates Myo Va through BMP-2. Furthermore, phosphorylation of Smad1/5/8 by BMP2 treatment confirmed that the BMP-2/Smad signaling pathway regulates Myo Va expression in Melan-a melanocytes. Smad-binding elements were found in the Myo Va promoter and phosphorylated Smad1/5/8 bind directly to the Myo Va promoter to activate Myo Va transcription and BMP-2 enhances this binding. These findings provide insight into a new role for BMP-2 in Melan-a melanocytes and a mechanism of regulation of Myo Va expression that may be beneficial in the treatment of albinism or hyperpigmentation disorders. [ABSTRACT FROM AUTHOR]

Background: Cyp19a1a is a key enzyme in the pathway that converts androgens into estrogen and is regulated by TGF-β signaling. Smad4 and FoxH1 are downstream effectors of TGF-β signaling and may play important roles in ovarian development in M. albus. Methods: We investigated the expression pattern of the Smad4 and FoxH1 using qRT‒PCR and immunofluorescence, then tested the changes of smad4 and foxh1 by qRT‒PCR after ovary incubation with FSH in vitro, and analysed the regulation of cyp19a1a transcription by Smad4 and FoxH1 by dual-luciferase reporter assays. Results: We found that Smad4 encoded a putative protein of 449 amino acids and harbored the three conserved domains typical of this protein family. Smad4 and foxh1 exhibited similar expression patterns during ovarian development and after FSH incubation, with Pearson's coefficients of 0.873 and 0.63–0.81, respectively. Furthermore, Smad4, FoxH1 and Cyp19a1a colocalized in the granulosa cells and theca cells of ovaries during the mid-to-late vitellogenic stage. Smad4 repressed cyp19a1a activity via SBE1 (− 1372/−1364) and SBE2 (− 415/−407) in the cyp19a1a promoter, whereas mutating SBE1 or SBE2 restored cyp19a1a promoter activity. Co-overexpression of Smad4 and FoxH1 significantly reduced cyp19a1a promoter activity. Conclusions: This study provides new insights into the potential functions of transcription factors Smad4 and FoxH1 in ovarian development and the transcriptional regulation mechanism of cyp19a1a in M. albus, which will reveal Smad4/FoxH1-mediated TGF-β signaling in reproduction and the regulation of the cyp19a1a. Plain English summary: Aromatase, encoded by cyp19a1a, is involved in ovarian development and plays an important role in the quality of eggs, as well the sex ratio, of the teleost fish, M. albus. The research on the transcriptional regulation of cyp19a1a has contributed to the understanding of its role in ovarian development. In previous study, it was shown that FoxH1 inhibits cyp19a1a transcription. In the present study, Smad4 was confirmed as a cyp19a1a transcriptional repressor and Smad4 may also coordinate with FoxH1 to repress cyp19a1a transcription. At present, we provide a new perspective for the transcriptional regulation of cyp19a1a by transcription factors Smad4 and FoxH1 in teleost fish ovary. In the future, the regulatory networks of Smad4 and FoxH1 will be further studied and the gene editing technology will be applied to screen specific regulatory factors of cyp191a1a gene, so as to alter the female cycle and modulate the sex ratio of the eggs production. Highlights: Smad4 and foxh1 were closely correlated with ovarian development, and Pearson's coefficient was 0.873. FSH incubation stimulated the expression of smad4 and foxh1 in the ovaries. Smad4, FoxH1 and Cyp19a1a colocalized in the granulosa cells and theca cells of ovaries. Smad4 and FoxH1 potentially synergistically suppress the activity of cyp19a1a promoter. [ABSTRACT FROM AUTHOR]

Juvenile polyposis syndrome (JPS) is an inherited autosomal dominant condition that predisposes to the development of juvenile polyps throughout the gastrointestinal (GI) tract, and it poses an increased risk of GI malignancy. Germline causative variants were identified in the SMAD4 gene in a subset (20%) of JPS cases. Most SMAD4 germline genetic variants published to date are missense, nonsense, and frameshift mutations. SMAD4 germline alterations predicted to result in aberrant splicing have rarely been reported. Here, we report two unrelated Italian families harboring two different SMAD4 intronic variants, c.424+5G>A and c.425-9A>G, which are clinically associated with colorectal cancer and/or juvenile GI polyps. In silico prediction analysis, in vitro minigene assays, and RT-PCR showed that the identified variants lead to aberrant SMAD4 splicing via the exonization of intronic nucleotides, resulting in a premature stop codon. This is expected to cause the production of a truncated protein. This study expands the landscape of SMAD4 germline genetic variants associated with GI polyposis and/or cancer. Moreover, it emphasizes the importance of the functional characterization of SMAD4 splicing variants through RNA analysis, which can provide new insights into genetic disease variant interpretation, enabling tailored genetic counseling, management, and surveillance of patients with GI polyposis and/or cancer. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide, with 20% of patients presenting with metastatic disease at diagnosis. TGF-β signaling plays a crucial role in various cellular processes, including growth, differentiation, apoptosis, epithelial-mesenchymal transition (EMT), regulation of the extracellular matrix, angiogenesis, and immune responses. TGF-β signals through SMAD proteins, which are intracellular molecules that transmit TGF-β signals from the cell membrane to the nucleus. Alterations in the TGF-β pathway and mutations in SMAD proteins are common in metastatic CRC (mCRC), making them critical factors in CRC tumorigenesis. This review first analyzes normal TGF-β signaling and then investigates its role in CRC pathogenesis, highlighting the mechanisms through which TGF-β influences metastasis development. TGF-β promotes neoangiogenesis via VEGF overexpression, pericyte differentiation, and other mechanisms. Additionally, TGF-β affects various elements of the tumor microenvironment, including T cells, fibroblasts, and macrophages, promoting immunosuppression and metastasis. Given its strategic role in multiple processes, we explored different strategies to target TGF-β in mCRC patients, aiming to identify new therapeutic options. [ABSTRACT FROM AUTHOR]

Introduction: Lung cancer is one of the most prevalent and deadly forms of cancer worldwide, accounting for a significant number of cancer-related deaths. Despite advances in diagnosis and treatment, the prognosis for lung cancer remains poor, emphasising the need for alternative and complementary therapeutic approaches. Transforming Growth Factor-beta (TGF-β) is a multifunctional cytokine that plays a crucial role in cell growth, differentiation, apoptosis and immune regulation. Suppressor of Mothers against Decapentaplegic (SMAD), a well known transcription factor, plays an essential role in carcinogenesis. Lutein, a naturally occurring carotenoid. Recent studies have suggested that lutein possess anticancer properties and could potentially be used as a therapeutic agent against various types of cancer. Aim: To assess the effect of lutein on TGF-β/SMAD2 gene expression in lung cancer cells. Materials and Methods: The present in-vitro study was carried in the Cancer and Stem Cell Laboratory Facility, Saveetha Dental College and Hospitals, Chennai, Tamil Nadu, India, from April 2023 to May 2023. The lung cancer cell line (A-549) was obtained from the National Centre for Cell Science (NCCS), Pune, India. Cell viability of lutein-treated lung cancer cells was assessed by 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell morphology was studied using a phase contrast microscope. The gene expression of TGF-β/SMAD2 was analysed using real-time Polymerase Chain Reaction (PCR), and the results were presented graphically as fold change. All data obtained were analysed by one-way Analysis of Variance (ANOVA) followed by Student’s t-test using PRISM software version 4. Results: The findings suggest that lutein had good cytotoxic effects on lung cancer cells. The Half-maximal inhibitory concentration (IC50) value was found to be 5.14 μM/mL. Lutein inhibited the TGF-β and SMAD2 gene expression signalling pathway and induced apoptosis in A549. Conclusion: Lutein significantly inhibited the TGF-β and SMAD2 gene expression signalling pathways, making it a potent anticancer drug. The downregulation of key genes involved in the TGF-β/SMAD2 pathway suggests a nuanced and intricate relationship between lutein and the regulatory mechanisms governing cellular signalling in lung cancer. These findings support the notion that lutein may exert a regulatory influence on the intricate balance of signalling cascades, offering a potential avenue for therapeutic intervention in lung cancer. [ABSTRACT FROM AUTHOR]

TGF-β1/Smads is a classic signaling pathway, which plays important roles in the development process of organisms. Black porgy Acanthopagrus schlegelii and red porgy Pagrus major are valuable economic fishes, and their hybrid offspring show excellent heterosis traits. Yet the molecular regulation mechanism of the heterosis traits is less clear. Here, we explored the TGF-β1/Smads pathway's molecular genetic information for heterosis in A. schlegelii ♂ × P. major ♀ (AP) and A. schlegelii ♀ × P. major ♂ (PA) in terms of growth and development. The mRNA expression levels of TGF-β1, TβR-I, TβR-II, and Smad2 genes in different developmental stages of A. schlegelii were detected. Furthermore, the expression levels of TGF-β1, TβR-I, TβR-II, and Smad2 genes in different tissues of adult (mRNA level) and larva (mRNA and protein level) of A. schlegelii, P. major, and their hybrids were determined by both real-time quantitative PCR and Western blot techniques. The results indicated the ubiquitous expression of these genes in all developmental stages of A. schlegelii and in all tested tissues of A. schlegelii, P. major, and its hybrids. Among them, the mRNA of TGF-β1, TβR-I, and TβR-II genes is highly expressed in the liver, gill, kidney, and muscle of black porgy, red porgy, and their hybrid offspring. There are significant changes in gene and protein expression levels in hybrid offspring, which indirectly reflect hybrid advantage. In addition, there was no correlation between protein and mRNA expression levels of Smad2 protein. The results provide novel data for the differential expression of growth and development genes between the reciprocal hybridization generation of black porgy and red porgy and its parents, which is conducive to further explaining the molecular regulation mechanism of heterosis in the growth and development of hybrid porgy. [ABSTRACT FROM AUTHOR]

Increasing epidemiological evidence has shown that PM 2.5 exposure is significantly associated with the occurrence of osteoporosis. It has been well demonstrated that PM 2.5 exposure enhanced the differentiation and function of osteoclasts by indirectly causing chronic inflammation, while the mechanism in osteoblasts remains unclear. In our study, toxic effects were evaluated by direct exposure of 20–80 μg/ml PM 2.5 to MC3T3-E1 cells and BMSCs. The results showed that PM 2.5 exposure did not affect cell viability via proliferation and apoptosis, but significantly inhibited osteoblast differentiation in a dose-dependent manner. Osteogenic transcription factors Runx2 and Sp7 and other biomarkers Alp and Ocn decreased after PM 2.5 exposure. RNA-seq revealed TGF-β signaling was involved in PM 2.5 exposure inhibited osteoblast differentiation, which led to P-Smad1/5 and P-Smad2 reduction in the nucleus by increasing the ubiquitination and degradation of Smad4. At last, the inflammation response increased in MC3T3-E1 cells with PM 2.5 exposure. Moreover, the mRNA levels of Mmp9 increased in bone marrow-derived macrophage cells treated with the conditional medium collected from MC3T3-E1 cells exposed to PM 2.5. Overall, these results indicated that PM 2.5 exposure inhibits osteoblast differentiation and concurrently increases the maturation of osteoclasts. Our study provides in-depth mechanistic insights into the direct impact of PM 2.5 exposure on osteoblast, which would indicate the unrecognized role of PM 2.5 on osteoporosis. • PM 2.5 exposure significantly inhibits osteoblast differentiation. • PM 2.5 inhibits TGFβ-Smad signaling via ubiquitin-dependent degradation of Smad4. • Smad4 replenish recovers the impaired differentiation with PM 2.5 treatment. • PM 2.5 elicits osteoblastic inflammatory response and promotes osteoclast function. [ABSTRACT FROM AUTHOR]

Simple Summary: The problem of low fertility in Tibetan pigs has a long history. In order to solve the problem of low fertility in Tibetan pigs, in this study, we successfully constructed cDNA libraries of the transcriptome from ovarian tissues of Tibetan and Yorkshire pigs using RNA-Seq technology, analyzed and screened the genes significantly enriched in the pathways closely related to the regulation of reproduction, and finally identified AR, CYP11A1, CYP17A1, INHBA, ARRB2, EGFR, ETS1, HSD17B1, IGF1R, MIF, SCARB1, and SMAD4 as important candidate genes. The 12 differentially expressed genes screened in relation to reproduction were validated using RT-qPCR. The results showed that six genes were highly significantly (p < 0.01) higher in expression in Tibetan pigs than in Yorkshire pigs, i.e., AR, CYP17A1, EGFR, ETS1, IGF1R, and SMAD4; on the other hand, six genes were highly significantly (p < 0.01) lower in expression in Tibetan pigs than in Yorkshire pigs, i.e., CYP11A1, INHBA, ARRB2, HSD17B, MIF, SCARB1. This study provides a theoretical basis for improving the regulatory genes in Tibetan pigs. The purpose of this study was to explore and verify genes that regulate the reproductive traits of Tibetan pigs at the mRNA level. The ovarian tissues of Tibetan pigs (TPs) and Yorkshire pigs (YPs) were selected as research objects, and cDNA libraries of the ovarian tissue transcripts of Tibetan pigs and Yorkshire pigs were successfully constructed by the RNA-Seq technique. A total of 651 differentially expressed genes (DEGs) were screened, including 414 up-regulated genes and 237 down-regulated genes. Through GO and KEGG enrichment analysis, it was found that these differentially expressed genes were significantly enriched in cell process, reproductive process, reproduction, cell proliferation, binding, and catalytic activity, as well as oxidative phosphorylation, endocrine resistance, thyroid hormone, Notch, and other signal transduction pathways. Genes significantly enriched in pathways closely related to reproductive regulation were analyzed and selected, and the AR, CYP11A1, CYP17A1, INHBA, ARRB2, EGFR, ETS1, HSD17B1, IGF1R, MIF, SCARB1, and SMAD4 genes were identified as important candidate genes. Twelve differentially expressed genes related to reproduction were verified by RT-qPCR. The results showed that the expression of the AR, CYP17A1, EGFR, ETS1, IGF1R, and SMAD4 genes was significantly higher in Tibetan pigs than in Yorkshire pigs, while the expression of the CYP11A1, INHBA, ARRB2, HSD17B, MIF, and SCARB1 genes in Tibetan pigs was significantly lower than in Yorkshire pigs. The purpose of this study is to provide a theoretical basis for exploring the molecular mechanism of reproductive trait effect genes and the application of molecular breeding in Tibetan pigs. [ABSTRACT FROM AUTHOR]

Objective(s): Liver fibrosis is a wound healing response characterized by excessive accumulation of extracellular matrix proteins. This study aimed to investigate the effects of resveratrol treatment on the TGF-β/SMAD signaling pathway and related biochemical parameters, apoptosis, and liver regeneration phenobarbital-CCl4 induced hepatic fibrosis rat model. Materials and Methods: This model was created through phenobarbital and CCl4 (0.2–0.35 ml/kg). Resveratrol (1 mg/kg/day) was administered to the fibrosis and control groups. Immunohistochemical staining was performed to evaluate αSMA, TGF-β1, and PCNA in liver tissue. The TUNEL method and Masson’s Trichome staining were used to determine apoptosis and collagen accumulation. AST, ALP, ALT, total protein, and total bilirubin levels were measured to determine biochemical status. SMAD2, SMAD3, SMAD4, and SMAD7 expression levels were measured to determine TGF-β1 related hepatic fibrosis. Results: The SMAD2, SMAD3, and SMAD4 mRNA expression levels were increased and the SMAD7 mRNA expression level was decreased in the fibrosis control group. The SMAD7 mRNA expression level was higher in the phenobarbital-CCl4 induced resveratrol treated group. Increased biochemical parameters indicating hepatic damage, increased number of apoptotic cells, and collagen accumulation surrounding the central vein were observed in the fibrosis group compared with the other groups. It was concluded that administration of resveratrol ameliorates the adverse effects of hepatic fibrosis by regulating biochemical parameters, controlling TGF-β1/SMAD signaling, enhancing tissue regeneration, and reducing apoptosis in liver cells. Conclusion: Resveratrol can be a beneficial option for the prevention of liver damage in a phenobarbital-CCl4 induced hepatic fibrosis.

Objectives: Treatment of metastatic colorectal cancer (mCRC) includes resection of liver metastases (LM), however, no validated biomarker identifies patients most likely to benefit from this procedure. This meta-analysis aimed to assess the impact of the most relevant molecular alterations in cancer-related genes of CRC (i.e., RAS, BRAF, SMAD4, PIK3CA) as prognostic markers of survival and disease recurrence in patients with mCRC surgically treated by LM resection. Methods: A systematic literature review was performed to identify studies reporting data regarding survival and/or recurrence in patients that underwent complete liver resection for CRC LM, stratified according to RAS, BRAF, PIK3CA, and SMAD4 mutational status. Hazard ratios (HRs) from multivariate analyses were pooled in the meta-analysis and various adjustment strategies for confounding factors were combined. The search was conducted in numerous databases, including MEDLINE (PubMed), Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL) (EBSCO host), and WHO Global Index Medicus, through March 18th, 2022. Meta-analyses, editorials, letters to the editor, case reports, studies on other primary cancers, studies with primary metastatic sites other than the liver, studies lacking specific oncological outcome variables or genetic data, non-English language studies, and studies omitting residual disease data from liver metastasectomy were excluded. The remaining 47 studies were summarized in a descriptive table which outlines the key characteristics of each study and final results were graphically presented. Results: RAS mutation status was negatively associated with overall survival (OS) (HR, 1.68; 95% CI, 1.54-1.84) and recurrence free survival (RFS) (HR, 1.46; 95% CI, 1.33-1.61). A negative association was also found for BRAF regarding OS (HR, 2.64; 95% CI, 2.15-3.24) and RFS (HR, 1.89; 95% CI, 1.32-2.73) and SMAD4 regarding OS (HR, 1.93; 95% CI, 1.56-2.38) and RFS (HR, 1.95; 95% CI, 1.31-2.91). For PIK3CA only three studies were eligible and no significant association with either OS or RFS could be highlighted. Conclusion: RAS, BRAF, and SMAD4 are negatively associated with OS and RFS in patients undergoing curative liver metastasectomy from colorectal cancer. No conclusion can be drawn for PIK3CA due to the limited literature availability. These data support the integration of RAS, BRAF, and SMAD4 mutational status in the surgical decision-making for colorectal liver metastasis. Nevertheless, we have to consider several limitations, the major ones being the pooling of results from studies that evaluated patient outcomes as either disease-free survival (DFS) or RFS; the inclusion of patients with minimal residual disease and unconsidered potential confounding factors, such as variability in resectability definitions, chemotherapy use, and a potential interaction between biological markers and pre- and post-resection pharmacological treatments. [ABSTRACT FROM AUTHOR]

Objective: The present study aims to investigate the specific protective effects and underlying mechanisms of Ganshuang granule (GSG) on dimethylnitrosamine (DMN)-induced hepatic fibrosis in rat models. Methods: Hepatic fibrosis was experimentally evoked in rats by DMN administration, and varying dosages of GSG were employed as an intervention. Hepatocellular damage was assessed by measuring serum levels of aminotransferase and bilirubin, accompanied by histopathological examinations of hepatic tissue. The hepatic concentrations of platelet-derived growth factor (PDGF) and transforming growth factor-β1 (TGF-β1) were quantitated via enzyme-linked immunosorbent assay (ELISA). The expression of α-smooth muscle actin (α-SMA) within hepatic tissue was evaluated using immunohistochemical techniques. The levels of hepatic interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and a spectrum of interleukins (IL-2, IL-4, IL-6, IL-10) were quantified by quantitative real-time PCR (qRT-PCR). Additionally, hepatic stellate cells (HSCs) were cultured in vitro and exposed to TNF-α in the presence of naringin, a principal component of GSG. The gene expression levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metallopeptidase-1 (MMP-1) in these cells were also quantified by qRT-PCR. Proliferative activity of HSCs was evaluated by the Cell Counting Kit-8 assay. Finally, alterations in Smad protein expression were analyzed through Western blotting. Results: Administration of GSG in rats with fibrosis resulted in reduced levels of serum aminotransferases and bilirubin, along with alleviation of histopathological liver injury. Furthermore, the fibrosis rats treated with GSG exhibited significant downregulation of hepatic TGF-β1, PDGF, and TNF-α levels. Additionally, GSG treatment led to increased mRNA levels of IFN-γ, IL-2, and IL-4, as well as decreased expression of α-SMA in the liver. Furthermore, treatment with naringin, a pivotal extract of GSG, resulted in elevated expression of MMP-1 and decreased levels of TIMP-1 in TNF-α-stimulated HSCs when compared to the control group. Additionally, naringin administration led to a reduction in Smad expression within the HSCs. Conclusion: GSG has the potential to mitigate fibrosis induced by DMN in rat models through the regulation of inflammatory and fibrosis factors. Notably, naringin, the primary extract of GSG, may exert a pivotal role in modulating the TGF-β-Smad signaling pathway. [ABSTRACT FROM AUTHOR]

Bone morphogenic protein (BMP) signaling plays an essential and highly conserved role in embryo axial patterning in animal species. However, in mammalian embryos, which develop inside the mother, early development includes a preimplantation stage, which does not occur in externally developing embryos. During preimplantation, the epiblast is segregated from extra-embryonic lineages that enable implantation and development in utero. Yet, the requirement for BMP signaling is imprecisely defined in mouse early embryos. Here, we show that, in contrast to previous reports, BMP signaling (SMAD1/5/9 phosphorylation) is not detectable until implantation when it is detected in the primitive endoderm – an extra-embryonic lineage. Moreover, preimplantation development appears to be normal following deletion of maternal and zygotic Smad4, an essential effector of canonical BMP signaling. In fact, mice lacking maternal Smad4 are viable. Finally, we uncover a new requirement for zygotic Smad4 in epiblast scaling and cavitation immediately after implantation, via a mechanism involving FGFR/ERK attenuation. Altogether, our results demonstrate no role for BMP4/SMAD4 in the first lineage decisions during mouse development. Rather, multipathway signaling among embryonic and extra-embryonic cell types drives epiblast morphogenesis postimplantation. [ABSTRACT FROM AUTHOR]

Juvenile polyposis syndrome (JPS) is a rare autosomal dominant disorder characterized by multiple juvenile polyps in the gastrointestinal tract, often associated with mutations in genes such as Smad4 and BMPR1A. This study explores the impact of Smad4 knock-out on the development of intestinal polyps using collaborative cross (CC) mice, a genetically diverse model. Our results reveal a significant increase in intestinal polyps in Smad4 knock-out mice across the entire population, emphasizing the broad influence of Smad4 on polyposis. Sex-specific analyses demonstrate higher polyp counts in knock-out males and females compared to their WT counterparts, with distinct correlation patterns. Line-specific effects highlight the nuanced response to Smad4 knock-out, underscoring the importance of genetic variability. Multimorbidity heat maps offer insights into complex relationships between polyp counts, locations, and sizes. Heritability analysis reveals a significant genetic basis for polyp counts and sizes, while machine learning models, including k-nearest neighbors and linear regression, identify key predictors, enhancing our understanding of juvenile polyposis genetics. Overall, this study provides new information on understanding the intricate genetic interplay in the context of Smad4 knock-out, offering valuable insights that could inform the identification of potential therapeutic targets for juvenile polyposis and related diseases. [ABSTRACT FROM AUTHOR]

Current chemical treatments for cerebrovascular disease and neurological disorders have limited efficacy in tissue repair and functional restoration. Induced pluripotent stem cells (iPSCs) present a promising avenue in regenerative medicine for addressing neurological conditions. iPSCs, which are capable of reprogramming adult cells to regain pluripotency, offer the potential for patient-specific, personalized therapies. The modulation of molecular mechanisms through specific growth factor inhibition and signaling pathways can direct iPSCs' differentiation into neural stem cells (NSCs). These include employing bone morphogenetic protein-4 (BMP-4), transforming growth factor-beta (TGFβ), and Sma-and Mad-related protein (SMAD) signaling. iPSC-derived NSCs can subsequently differentiate into various neuron types, each performing distinct functions. Cell transplantation underscores the potential of iPSC-derived NSCs to treat neurodegenerative diseases such as Parkinson's disease and points to future research directions for optimizing differentiation protocols and enhancing clinical applications. [ABSTRACT FROM AUTHOR]

Development of the mammalian oocyte requires physical contact with the surrounding granulosa cells of the follicle, which provide it with essential nutrients and regulatory signals. This contact is achieved through specialized filopodia, termed transzonal projections (TZPs), that extend from the granulosa cells to the oocyte surface. Transforming growth factor (TGFβ) family ligands produced by the oocyte increase the number of TZPs, but how they do so is unknown. Using an inducible Cre recombinase strategy together with expression of green fluorescent protein to verify Cre activity in individual cells, we examined the effect of depleting the canonical TGFβ mediator, SMAD4, in mouse granulosa cells. We observed a 20–50% decrease in the total number of TZPs in SMAD4-depleted granulosa cell-oocyte complexes, and a 50% decrease in the number of newly generated TZPs when the granulosa cells were reaggregated with wild-type oocytes. Three dimensional image analysis revealed that TZPs of SMAD4-depleted cells were longer than controls and more frequently oriented towards the oocyte. Strikingly, the transmembrane proteins, N-cadherin and Notch2, were reduced by 50% in SMAD4-depleted cells. SMAD4 may thus modulate a network of cell adhesion proteins that stabilize the attachment of TZPs to the oocyte, thereby amplifying signalling between the two cell types. [ABSTRACT FROM AUTHOR]

Renal fibrosis (RF) stands as a pivotal pathological process in the advanced stages of chronic kidney disease (CKD), and impeding its progression is paramount for delaying the advancement of CKD. The miR-10 family, inclusive of miR-10a and miR-10b, has been implicated in the development of various fibrotic diseases. Nevertheless, the precise role of miR-10 in the development of RF remains enigmatic. In this study, we utilized both an in vivo model involving unilateral ureteral obstruction (UUO) in mice and an in vitro model employing TGF-β1 stimulation in HK-2 cells to unravel the mechanism underlying the involvement of miR-10a/b in RF. The findings revealed heightened expression of miR-10a and miR-10b in the kidneys of UUO mice, accompanied by a substantial increase in p-Smad3 and renal fibrosis-related proteins. Conversely, the deletion of these two genes led to a notable reduction in p-Smad3 levels and the alleviation of RF in mouse kidneys. In the in vitro model of TGF-β1-stimulated HK-2 cells, the co-overexpression of miR-10a and miR-10b fostered the phosphorylation of Smad3 and RF, while the inhibition of miR-10a and miR-10b resulted in a decrease in p-Smad3 levels and RF. Further research revealed that miR-10a and miR-10b, through binding to the 3'UTR region of Vasohibin-1 (VASH-1), suppressed the expression of VASH-1, thereby promoting the elevation of p-Smad3 and exacerbating the progression of RF. The miR-10 family may play a pivotal role in RF. [ABSTRACT FROM AUTHOR]

Cells use signaling pathways to sense and respond to their environments. The transforming growth factor-β (TGF-β) pathway produces context-specific responses. Here, we combined modeling and experimental analysis to study the dependence of the output of the TGF-β pathway on the abundance of signaling molecules in the pathway. We showed that the TGF-β pathway processes the variation of TGF-β 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-β 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-β 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. Author summary: The same cell signal can often initiate different signaling responses depending on the cellular context, but the underlying control principle remains unclear. In this study, we explored the complex world of cell signaling, focusing on the transforming growth factor-β (TGF-β) pathway that plays a crucial role in regulating fundamental cellular processes such as cell proliferation, migration and differentiation. We were intrigued by how variations in the abundance of signaling molecules could impact the responses of the TGF-β pathway in different types of cells and within individual cells. Our investigation led to an insightful discovery—the "minority control rule" in the TGF-β pathway, similar to Liebig's law of the minimum. This minority control rule suggests that the activity of TGF-β signaling is governed by the TGF-β receptor present at the lowest level, much like the shortest wood plate determining the capacity of a cask. By uncovering this principle, we shed light on the significance of considering the relative abundance of signaling proteins, especially receptors, in designing strategies aimed at modulating the activities of signaling pathways for therapeutic purposes. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms for oocyte maturation and optimizing the protocols for in vitro maturation (IVM) are greatly important for improving developmental potential of IVM oocytes. The miRNAs expressed in cumulus cells (CCs) play important roles in oocyte maturation and may be used as markers for selection of competent oocytes/embryos. Although a recent study from our group identified several new CCs-expressed miRNAs that regulate cumulus expansion (CE) and CC apoptosis (CCA) in mouse oocytes, validation of these findings and further investigation of mechanisms of action in other model species was essential before wider applications. By using both in vitro and in vivo pig oocyte models with significant differences in CE, CCA and developmental potential, the present study validated that miR-149 and miR-31 improved CE and developmental potential while suppressing CCA of pig oocytes. We demonstrated that miR-149 and miR-31 targeted SMAD family member 6 (SMAD6) and transforming growth factor β2 (TGFB2), respectively, in the transforming growth factor-β (TGF-β) signaling. Furthermore, both miR-149 and miR-31 increased CE and decreased CCA via activating SMAD family member 2 (SMAD2) and increasing the expression of SMAD2 and SMAD family member 4. In conclusion, the present results show that miR-149 and miR-31 improved CE and developmental potential while suppressing CCA of pig oocytes by activating the TGF-β signaling, suggesting that they might be used as markers for pig oocyte quality. • Both in vitro and in vivo pig oocyte models with significant differences in cumulus cell (CC) expansion (CE), apoptosis (CCA) and developmental potential were used. • The expression levels of miR-149 and miR-31 in pig CCs were significantly higher in good than in poor in vitro or in vivo oocyte models. • Both miR-149 and miR-31 improved CE and developmental potential while suppressing CCA of pig oocytes. • MiR-149 and miR-31 increased CE and decreased CCA via activating SMAD2 and increasing the expression of SMAD2 and SMAD4 in the TGF-β signaling. [ABSTRACT FROM AUTHOR]

Background: JAK inhibitors are well known for the treatment of rheumatoid arthritis (RA), but whether they can be used to treat pulmonary fibrosis, a common extra‐articular disease of RA, remains to be clarified. Methods: A jak2 inhibitor, CEP33779 (CEP), was administered to a rat model of RA‐associated interstitial lung disease to observe the degree of improvement in both joint swelling and pulmonary fibrosis. HFL1 cells were stimulated with TGF‐β1 to observe the expression of p‐JAK2. Then, different concentrations of related gene inhibitors (JAK2, TGFβ‐R1/2, and p‐STAT3) or silencers (STAT3, JAK2) were administered to HFL1 cells, and the expression levels of related proteins were detected to explore the underlying mechanisms of action. Results: CEP not only reduced the degree of joint swelling and inflammation in rats but also improved lung function, inhibited the pro‐inflammatory factors IL‐1β and IL‐6, reduced lung inflammation and collagen deposition, and alleviated lung fibrosis. CEP decreased the expression levels of TGFβ‐R2, p‐SMAD, p‐STAT3, and ECM proteins in rat lung tissues. TGF‐β1 induced HFL1 cells to highly express p‐JAK2, with the most pronounced expression at 48 h. The levels of p‐STAT3, p‐SMAD3, and ECM‐related proteins were significantly reduced after inhibition of either JAK2 or STAT3. Conclusion: JAK2 inhibitors may be an important and novel immunotherapeutic drug that can improve RA symptoms while also delaying or blocking the development of associated pulmonary fibrotic disease. The mechanism may be related to the downregulation of p‐STAT3 protein via inhibition of the JAK2/STAT signaling pathway, which affects the phosphorylation of SMAD3. [ABSTRACT FROM AUTHOR]

Metabolic dysfunction of the extracellular matrix (ECM) is one of the primary causes of intervertebral disc degeneration (IVDD). Previous studies have demonstrated that the transcription factor Brachyury (Bry) has the potential to promote the synthesis of collagen II and aggrecan, while the specific mechanism is still unknown. In this study, we used a lipopolysaccharide (LPS)-induced model of nucleus pulposus cell (NPC) degeneration and a rat acupuncture IVDD model to elucidate the precise mechanism through which Bry affects collagen II and aggrecan synthesis in vitro and in vivo. First, we confirmed Bry expression decreased in degenerated human nucleus pulposus (NP) cells (NPCs). Knockdown of Bry exacerbated the decrease in collagen II and aggrecan expression in the lipopolysaccharide (LPS)-induced NPCs degeneration in vitro model. Bioinformatic analysis indicated that Smad3 may participate in the regulatory pathway of ECM synthesis regulated by Bry. Chromatin immunoprecipitation followed by quantitative polymerase chain reaction (ChIP-qPCR) and luciferase reporter gene assays demonstrated that Bry enhances the transcription of Smad3 by interacting with a specific motif on the promoter region. In addition, Western blot and reverse transcription-qPCR assays demonstrated that Smad3 positively regulates the expression of aggrecan and collagen II in NPCs. The following rescue experiments revealed that Bry-mediated regulation of ECM synthesis is partially dependent on Smad3 phosphorylation. Finally, the findings from the in vivo rat acupuncture-induced IVDD model were consistent with those obtained from in vitro assays. In conclusion, this study reveals that Bry positively regulates the synthesis of collagen II and aggrecan in NP through transcriptional activation of Smad3. NEW & NOTEWORTHY: Mechanically, in the nucleus, Bry enhances the transcription of Smad3, leading to increased expression of Smad3 protein levels; in the cytoplasm, elevated substrate levels further lead to an increase in the phosphorylation of Smad3, thereby regulating collagen II and aggrecan expression. Further in vivo experiments provide additional evidence that Bry can alleviate IVDD through this mechanism. [ABSTRACT FROM AUTHOR]

The pathogenesis of glomerular diseases is strongly influenced by abnormal extracellular matrix (ECM) deposition in mesangial cells. Dipeptidyl peptidase IV (DPPIV) enzyme family contains DPP8 and DPP9, which are involved in multiple diseases. However, the pathogenic roles of DPP8 and DPP9 in mesangial cells ECM deposition remain unclear. In this study, we observed that DPP8 and DPP9 were significantly increased in glomerular mesangial cells and podocytes in CKD patients compared with healthy individuals, and DPP9 levels were higher in the urine of IgA nephropathy (IgAN) patients than in control urine. Therefore, we further explored the mechanism of DPP8 and DPP9 in mesangial cells and revealed a significant increase in the expression of DPP8 and DPP9 in human mesangial cells (HMCs) following TGF-β1 stimulation. Silencing DPP8 and DPP9 by siRNAs alleviated the expression of ECM-related proteins including collagen Ⅲ, collagen Ⅳ, fibronectin, MMP2, in TGF-β1-treated HMCs. Furthermore, DPP8 siRNA and DPP9 siRNA inhibited TGF-β1-induced phosphorylation of Smad2 and Smad3, as well as the phosphorylation of Akt in HMCs. The findings suggested the inhibition of DPP8/9 may alleviate HMCs ECM deposition induced by TGF-β1 via suppressing TGF-β1/Smad and AKT signaling pathways. [Display omitted] • The expression of DPP8 and DPP9 was up-regulated in glomeruli of CKD patients. • DPP8/DPP9 may interfere with TGF-β1/Smad and Akt signaling pathways. • DPP8/DPP9 may have the therapeutic potential for CKD patients with excessive ECM accumulation. [ABSTRACT FROM AUTHOR]

Transforming growth factor β (TGF-β) is a pleiotropic cytokine that is widely distributed throughout the body. Its receptor proteins, TGF-β type I and type II receptors, are also ubiquitously expressed. Therefore, the regulation of various signaling outputs in a context-dependent manner is a critical issue in this field. Smad proteins were originally identified as signal-activated transcription factors similar to signal transducer and activator of transcription proteins. Smads are activated by serine phosphorylation mediated by intrinsic receptor dual specificity kinases of the TGF-β family, indicating that Smads are receptor-restricted effector molecules downstream of ligands of the TGF-β family. Smad proteins have other functions in addition to transcriptional regulation, including post-transcriptional regulation of micro-RNA processing, premRNA splicing, and m6 A methylation. Recent technical advances have identified a novel landscape of Smad-dependent signal transduction, including regulation of mitochondrial function without involving regulation of gene expression. Therefore, Smad proteins are receptor-activated transcription factors and also act as intracellular signaling modulators with multiple modes of function. In this review, we discuss the role of Smad proteins as receptor-activated transcription factors and beyond. We also describe the functional differences between Smad2 and Smad3, two receptor-activated Smad proteins downstream of TGF-β, activin, myostatin, growth and differentiation factor (GDF) 11, and Nodal. [ABSTRACT FROM AUTHOR]

Smad proteins influence the TGFβ signaling pathway, which plays an important role in the progression of atherosclerosis. The aim of our study was to investigate the association between the rs17228212 polymorphism of the SMAD3 gene and advanced carotid atherosclerosis in Slovenian subjects and to investigate the effect of the rs17228212 SMAD3 polymorphism on the expression of SMAD3 in endarterectomy sequesters. In this cross-sectional case-control study, 881 unrelated Caucasians were divided into two groups. The first group included 308 patients with advanced carotid atherosclerosis of the common or internal carotid artery with stenosis greater than 75% that underwent a revascularization procedure (cases). The control group consisted of 573 subjects without hemodynamically significant carotid atherosclerosis. We analyzed the rs17228212 polymorphism of the SMAD3 gene using the StepOne real-time polymerase chain reaction system and TaqMan SNP genotyping assay. The results in the two genetic models showed a statistically significant association, codominant (OR 4.05; CI 1.10–17.75; p = 0.037) and dominant (OR 3.60; CI 1.15–15.45; p = 0.045). An immunohistochemical analysis of SMAD3 expression was conducted for 26 endarterectomy specimens. The T allele of the rs17228212 SMAD3 gene was shown to be associated with an increased numerical area density of SMAD3-positive cells in carotid plaques. [ABSTRACT FROM AUTHOR]

Background: Osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) is an essential event in alveolar bone regeneration. Oxidative stress may be the main inhibiting factor of hPDLSC osteogenesis. Superoxide dismutase 2 (SOD2) is a key antioxidant enzyme, but its effect on hPDLSC osteogenic differentiation is unclear. Methods: Several surface markers were detected by flow cytometry, and the differentiation potential of hPDLSCs was validated by alkaline phosphatase (ALP), Alizarin Red S, and Oil Red O staining. Osteogenic indicators of hPDLSCs were detected by real‐time quantitative polymerase chain reaction (RT‐qPCR), Western blotting, and ALP staining. Furthermore, alveolar bone defect rat models were analyzed through micro‐CT, hematoxylin and eosin, and Masson staining. The intracellular reactive oxygen species (ROS) level was evaluated by a ROS assay kit. Finally, the expression of SOD2, Smad3, and p‐Smad3 in hPDLSCs was detected by RT‐qPCR and Western blotting (WB). Results: SOD2 positively regulated the gene and protein expressions of ALP, BMP6, and RUNX2 in hPDLSCs (p < 0.05). Ideal bone formation and continuous cortical bone were obtained by transplanting LV‐SOD2 hPDLSCs (lentivirus vector for overexpressing SOD2 in hPDLSCs) in vivo. Exogenous H2O2 downregulated osteogenic indicators (ALP, BMP6, RUNX2) in hPDLSCs (p < 0.05); this was reversed by overexpression of SOD2. WB results showed that the Smad3 and p‐Smad3 signaling pathways participated in the osteogenic process of SOD2 in hPDLSCs. Conclusion: SOD2 positively regulated hPDLSC osteogenic differentiation in vitro and in vivo. Mechanistically, SOD2 promotes hPDLSC osteogenic differentiation by regulating the phosphorylation of Smad3 to scavenge ROS. This work provides a theoretical basis for the treatment of alveolar bone regeneration. [ABSTRACT FROM AUTHOR]

Background: Bone morphogenetic protein 4 (BMP4) is a potent inhibitor of breast cancer metastasis. However, a tumor-promoting effect of BMP4 is reported in other tumor types, especially when SMAD4 is inactive. Methods: To assess the requirement for SMAD4 in BMP4-mediated suppression of metastasis, we knocked down SMAD4 in two different breast tumors and enforced SMAD4 expression in a third line with endogenous SMAD4 deletion. In addition, we assessed the requirement for SMAD4 in tumor cell-specific BMP signalling by expression of a constitutively active BMP receptor. Delineation of genes regulated by BMP4 in the presence or absence of SMAD4 was assessed by RNA sequencing and a BMP4-induced gene, MYO1F was assessed for its role in metastasis. Genes regulated by BMP4 and/or SMAD4 were assessed in a publicly available database of gene expression profiles of breast cancer patients. Results: In the absence of SMAD4, BMP4 promotes primary tumor growth that is accompanied by increased expression of genes associated with DNA replication, cell cycle, and MYC signalling pathways. Despite increased primary tumor growth, BMP4 suppresses metastasis in the absence of tumor cell expression of SMAD4. Consistent with the anti-metastatic activity of BMP4, enforced signalling through the constitutively active receptor in SMAD4 positive tumors that lacked BMP4 expression still suppressed metastasis, but in the absence of SMAD4, the suppression of metastasis was largely prevented. Thus BMP4 is required for suppression of metastasis regardless of tumor SMAD4 status. The BMP4 upregulated gene, MYO1F, was shown to be a potent suppressor of breast cancer metastasis. Gene signature upregulated by BMP4 in the absence of SMAD4 was associated with poor prognosis in breast cancer patients, whereas gene signature upregulated by BMP4 in the presence of SMAD4 was associated with improved prognosis. Conclusions: BMP4 expression is required for suppression of metastasis regardless of the SMAD4 status of the tumor cells. Since BMP4 is a secreted protein, we conclude that it can act both in an autocrine manner in SMAD4-expressing tumor cells and in a paracrine manner on stromal cells to suppress metastasis. Deletion of SMAD4 from tumor cells does not prevent BMP4 from suppressing metastasis via a paracrine mechanism. [ABSTRACT FROM AUTHOR]

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic pulmonary disease that is characterized by an excessive accumulation of extracellular matrix (ECM) proteins (e.g. collagens) in the parenchyma, which ultimately leads to respiratory failure and death. While current therapies exist to slow the progression, no therapies are available to resolve fibrosis. Methods: We characterized the O-linked N-Acetylglucosamine (O-GlcNAc) transferase (OGT)/O-GlcNAc axis in IPF using single-cell RNA-sequencing (scRNA-seq) data and human lung sections and isolated fibroblasts from IPF and non-IPF donors. The underlying mechanism(s) of IPF were further investigated using multiple experimental models to modulate collagen expression and accumulation by genetically and pharmacologically targeting OGT. Furthermore, we hone in on the transforming growth factor-beta (TGF-b) effector molecule, Smad3, by co-expressing it with OGT to determine if it is modified and its subsequent effect on Smad3 activation. Results: We found that OGT and O-GlcNAc levels are upregulated in patients with IPF compared to non-IPF. We report that the OGT regulates collagen deposition and fibrosis resolution, which is an evolutionarily conserved process demonstrated across multiple species. Co-expression of OGT and Smad3 showed that Smad3 is O-GlcNAc modified. Blocking OGT activity resulted in decreased phosphorylation at Ser-423/425 of Smad3 attenuating the effects of TGF-b1 induced collagen expression/deposition. Conclusion: OGT inhibition or knockdown successfully blocked and reversed collagen expression and accumulation, respectively. Smad3 is discovered to be a substrate of OGT and its O-GlcNAc modification(s) directly affects its phosphorylation state. These data identify OGT as a potential target in pulmonary fibrosis resolution, as well as other diseases that might have aberrant ECM/collagen accumulation. [ABSTRACT FROM AUTHOR]

The alteration of metabolic processes has been found to have significant impacts on the development of hepatocellular carcinoma (HCC). Nevertheless, the effects of dysfunction of tyrosine metabolism on the development of HCC remains to be discovered. This research demonstrated that tyrosine hydroxylase (TH), which responsible for the initial and limiting step in the bio-generation of the neuro-transmitters dopamine and adrenaline, et al. was shown to be reduced in HCC. Increased expression of TH was found facilitates the survival of HCC patients. In addition, decreased TH indicated larger tumor size, much more numbers of tumor, higher level of AFP, and the presence of cirrhosis. TH effectively impairs the growth and metastasis of HCC cells, a process dependent on the phosphorylation of serine residues (S19/S40). TH directly binds to Smad2 and hinders the cascade activation of TGFβ/Smad signaling with the treatment of TGFβ1. In summary, our study uncovered the non-metabolic functions of TH in the development of HCC and proposes that TH might be a promising biomarker for diagnosis as well as an innovative target for metastatic HCC. [ABSTRACT FROM AUTHOR]

We investigated the effects of transcriptional intermediary factor 1γ (TIF1γ) and SMAD4 on the proliferation and liver metastasis of colorectal cancer (CRC) cells through knockdown of TIF1γ and/or SMAD4 and knockdown of TIF1γ and/or restoration of SMAD4 expression. Furthermore, we examined TIF1γ and SMAD4 expression in human primary CRC and corresponding liver metastatic CRC specimens. TIF1γ promoted but SMAD4 inhibited the proliferation of CRC cells by competitively binding to activated SMAD2/SMAD3 complexes and then reversely regulating c-Myc, p21, p27, and cyclinA2 levels. Surprisingly, both TIF1γ and SMAD4 reduced the liver metastasis of all studied CRC cell lines via inhibition of MEK/ERK pathway-mediated COX-2, Nm23, uPA, and MMP9 expression. In patients with advanced CRC, reduced TIF1γ or SMAD4 expression was correlated with increased invasion and liver metastasis and was a significant, independent risk factor for recurrence and survival after radical resection. Patients with advanced CRC with reduced TIF1γ or SAMD4 expression had higher recurrence rates and shorter overall survival. TIF1γ and SMAD4 competitively exert contrasting effects on cell proliferation but act complementarily to suppress the liver metastasis of CRC via MEK/ERK pathway inhibition. Thus, reduced TIF1γ or SMAD4 expression in advanced CRC predicts earlier liver metastasis and poor prognosis. [ABSTRACT FROM AUTHOR]

Objective: According to the response-to-retention hypothesis, the inception of atherosclerosis is attributed to thedeposition and retention of lipoprotein in the arterial intima, facilitated by altered proteoglycans with hyperelongatedglycosaminoglycan (GAG) chains. Recent studies have elucidated a signaling pathway whereby transforming growthfactor-β (TGF-β) promotes the expression of genes linked to proteoglycan GAG chain elongation (CHSY1 and CHST11)via reactive oxygen species (ROS) and the downstream phosphorylation of ERK1/2 and Smad2L. Atorvastatin is knownto exhibit pleiotropic effects, including antioxidant and anti-inflammatory. The purpose of the present research wasto ascertain the influence of atorvastatin on TGF-β-stimulated expression of CHST11 and CHSY1 and associatedsignaling pathways using an in vitro model.Materials and Methods: In this experimental study, vascular smooth muscle cells (VSMCs) were pre-incubatedwith atorvastatin (0.1-10 μM) prior to being stimulated with TGF-β (2 ng/ml). The experiment aimed to evaluate thephosphorylation levels of Smad2C, Smad2L, ERK1/2, the NOX p47phox subunit, ROS production, and the mRNAexpression of CHST11 and CHSY1.Results: Our research results indicated that atorvastatin inhibited TGF-β-stimulated CHSY1 and CHST11 mRNAexpression. Further experiments showed that atorvastatin diminished TGF-β-stimulated ROS production and weakenedTGF-β-stimulated phosphorylation of p47phox, ERK1/2, and Smad2L; however, we observed no effect on the TGF-β-Smad2C pathway.Conclusion: These data suggest that atorvastatin demonstrates anti-atherogenic properties through the modulationof the ROS-ERK1/2-Smad2L signaling pathway. This provides valuable insight into the potential mechanisms by whichatorvastatin exerts its pleiotropic effects against atherosclerosis.

Non-small-cell lung carcinoma (NSCLC) is the most common lung cancer and one of the pioneer tumors in which immunotherapy has radically changed patients' outcomes. However, several issues are emerging and their implementation is required to optimize immunotherapy-based protocols. In this work, we investigate the ability of the Bromodomain and Extra-Terminal protein inhibitors (BETi) to stimulate a proficient anti-tumor immune response toward NSCLC. By using in vitro, ex-vivo, and in vivo models, we demonstrate that these epigenetic drugs specifically enhance Natural Killer (NK) cell cytotoxicity. BETi down-regulate a large set of NK inhibitory receptors, including several immune checkpoints (ICs), that are direct targets of the transcriptional cooperation between the BET protein BRD4 and the transcription factor SMAD3. Overall, BETi orchestrate an epigenetic reprogramming that leads to increased recognition of tumor cells and the killing ability of NK cells. Our results unveil the opportunity to exploit and repurpose these drugs in combination with immunotherapy. Combination of BET inhibitors (BETi) with immunotherapy has been reported to be synergic for the treatment of non-small cell lung carcinoma (NSCLC). Here, the authors show that BETi-induced epigenetic reprogramming downregulates the expression of NK cell inhibitory receptors on NK cells, increasing their activation and cytotoxicity against NSCLC. [ABSTRACT FROM AUTHOR]

Background: Pancreatic cancer stem cells are crucial for tumorigenesis and cancer metastasis. Presently, long non-coding RNAs were found to be associated with Pancreatic Ductal Adenocarcinoma stemness characteristics but the underlying mechanism is largely known. Here, we aim to explore the function of LINC00909 in regulating pancreatic cancer stemness and cancer metastasis. Methods: The expression level and clinical characteristics of LINC00909 were verified in 80-paired normal pancreas and Pancreatic Ductal Adenocarcinoma tissues from Guangdong Provincial People's Hospital cohort by in situ hybridization. RNA sequencing of PANC-1 cells with empty vector or vector encoding LINC00909 was experimented for subsequent bioinformatics analysis. The effect of LINC00909 in cancer stemness and metastasis was examined by in vitro and in vivo experiments. The interaction between LINC00909 with SMAD4 and the pluripotency factors were studied. Results: LINC00909 was generally upregulated in pancreatic cancer tissues and was associated with inferior clinicopathologic features and outcome. Over-expression of LINC00909 enhanced the expression of pluripotency factors and cancer stem cells phenotype, while knock-down of LINC00909 decreased the expression of pluripotency factors and cancer stem cells phenotype. Moreover, LINC00909 inversely regulated SMAD4 expression, knock-down of SMAD4 rescued the effect of LINC00909-deletion inhibition on pluripotency factors and cancer stem cells phenotype. These indicated the effect of LINC00909 on pluripotency factors and CSC phenotype was dependent on SMAD4 and MAPK/JNK signaling pathway, another downstream pathway of SMAD4 was also activated by LINC00909. Specifically, LINC00909 was localized in the cytoplasm in pancreatic cancer cells and decreased the stability the SMAD4 mRNA. Finally, we found over-expression of LINC00909 not only accelerated tumor growth in subcutaneous mice models, but also facilitated tumorigenicity and spleen metastasis in orthotopic mice models. Conclusion: We demonstrate LINC00909 inhibits SMAD4 expression at the post-transcriptional level, which up-regulates the expression of pluripotency factors and activates the MAPK/JNK signaling pathway, leading to enrichment of cancer stem cells and cancer metastasis in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Objective: Non-small cell lung cancer (NSCLC) often exhibits resistance to radiotherapy, posing significant treatment challenges. This study investigates the role of SMAD3 in NSCLC, focusing on its potential in influencing radiosensitivity via the ITGA6/PI3K/Akt pathway. Methods: The study utilized gene expression data from the GEO database to identify differentially expressed genes related to radiotherapy resistance in NSCLC. Using the GSE37745 dataset, prognostic genes were identified through Cox regression and survival analysis. Functional roles of target genes were explored using Gene Set Enrichment Analysis (GSEA) and co-expression analyses. Gene promoter methylation levels were assessed using databases like UALCAN, DNMIVD, and UCSC Xena, while the TISCH database provided insights into the correlation between target genes and CAFs. Experiments included RT-qPCR, Western blot, and immunohistochemistry on NSCLC patient samples, in vitro studies on isolated CAFs cells, and in vivo nude mouse tumor models. Results: Fifteen key genes associated with radiotherapy resistance in NSCLC cells were identified. SMAD3 was recognized as an independent prognostic factor for NSCLC, linked to poor patient outcomes. High expression of SMAD3 was correlated with low DNA methylation in its promoter region and was enriched in CAFs. In vitro and in vivo experiments confirmed that SMAD3 promotes radiotherapy resistance by activating the ITGA6/PI3K/Akt signaling pathway. Conclusion: High expression of SMAD3 in NSCLC tissues, cells, and CAFs is closely associated with poor prognosis and increased radiotherapy resistance. SMAD3 is likely to enhance radiotherapy resistance in NSCLC cells by activating the ITGA6/PI3K/Akt signaling pathway. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to determine the effects of obesity and biological sex on myostatin expression in humans and to examine the direct effects of myostatin, SMAD2, and SMAD3 on insulin signaling in primary human skeletal muscle cells (HSkMCs). For cohort 1, 15 lean [body mass index (BMI): 22.1 ± 0.5 kg/m²; n = 8 males; n = 7 females] and 14 obese (BMI: 40.6 ± 1.4 kg/m²; n = 7 males; n = 7 females) individuals underwent skeletal muscle biopsies and an oral glucose tolerance test. For cohort 2, 14 young lean (BMI: 22.4 ± 1.9 kg/m2; n = 6 males; n = 8 females) and 14 obese (BMI: 39.3 ± 7.9 kg/m²; n = 6 males; n = 8 females) individuals underwent muscle biopsies for primary HSkMC experiments. Plasma mature myostatin (P = 0.041), skeletal muscle precursor myostatin (P = 0.048), and skeletal muscle SMAD3 (P = 0.029) were elevated in obese females compared to lean females, and plasma mature myostatin (r = 0.58, P = 0.029) and skeletal muscle SMAD3 (r = 0.56, P = 0.037) were associated with insulin resistance in females but not males. Twenty-four hours of myostatin treatment impaired insulin signaling in primary HSkMCs derived from females (P < 0.024) but not males. Overexpression of SMAD3, but not SMAD2, impaired insulin-stimulated AS160 phosphorylation in HSkMCs derived from lean females (~27%, P = 0.040), whereas silencing SMAD3 improved insulin-stimulated AS160 phosphorylation and insulin-stimulated glucose uptake (25%, P < 0.014) in HSkMCs derived from obese females. These results suggest for the first time that myostatin-induced impairments in skeletal muscle insulin signaling are sex specific and that increased body fat in females is associated with detrimental elevations in myostatin and SMAD3, which contribute to obesity-related insulin resistance. [ABSTRACT FROM AUTHOR]

Objective: Exploring the effects of miR-155 regulation of SMAD2 expression in podocyte injury as well as macrophage inflammatory response in mouse lupus nephritis. Methods: The experimental mice were randomly divided into blank, model, AAV9-miR-NC, AAV9-miR-155, AAV9-miR-anti, and AAV9-miR-anti-NC groups, with 8 mice in each group, of which the blank group was C57BL/6 mice, and the rest of the groups were MRL/lpr mice, and the groups were treated and sampled accordingly. The presence or absence of a binding site for miR-155 and SMAD2 was predicted by target genes, an online target gene prediction website. Dual luciferase reporter gene analysis system to validate the targeting relationship between miR-155 and SMAD2. Determination of 24 h urinary protein content in each group of mice by Caumas Brilliant Blue method. Hematoxylin-Eosin staining was used to observe the kidney tissues of mice ; qRT-PCR to detect the expression level of miR-155 in kidney tissues of each group. Western blot was used to detect nephrin, P-cadherin and SMAD2 protein expression in renal tissues. Immunofluorescence assay to detect the expression of inflammatory factors (IL-6, TNF-α) in mice. Results: Compared with the blank group, mice in the model group had elevated urinary protein, severe renal pathological damage, and decreased expression levels of nephrin, P-cadherin, and SMAD2 while increased expression levels of IL-6 and TNF-α in renal tissues (P<0.05). Compared with the model group and AAV9-miR-NC group, mice in the model group of AAV9- miR-155 group showed elevated urinary protein, obvious renal pathological damage, and obvious elevation of miR-155 in renal tissues, whereas the expression levels of nephrin, P-cadherin, and SMAD2 were decreased (P<0.05) whereas the fluorescence intensity of IL-6 and TNF-α was enhanced significantly; Compared with the model and AAV9-miR-anti-NC groups, mice in the AAV9-miR-anti group showed decreased urinary protein, improved renal pathological injury, decreased miR-155 expression, and increased expression levels of nephrin, P-cadherin, and SMAD2 compared to the model group (P<0.05) whereas the fluorescence intensities of IL-6 and TNF-α decreased; In the model group, AAV9-miR-NC group, and AAV9-miR-anti-NC group mice, the differences in the above indexes were not statistically significant (P>0.05). Dual luciferase reporter gene assay showed that miR-155 inhibited the fluorescence activity of wild-type SMAD2 cells and targeted the regulation of SMAD2 expression. Conclusion: High expression of miR-155 exacerbated podocyte injury and inflammatory response in lupus nephritis in mice by regulating SMAD2, whereas inhibition of miR-155 expression attenuated podocyte injury and inflammatory response in mice. [ABSTRACT FROM AUTHOR]

Endometriosis is linked to increased infertility and pregnancy complications due to defective endometrial decidualization. We hypothesized that identification of altered signaling pathways during decidualization could identify the underlying cause of infertility and pregnancy complications. Our study reveals that transforming growth factor β (TGFβ) pathways are impaired in the endometrium of individuals with endometriosis, leading to defective decidualization. Through detailed transcriptomic analyses, we discovered abnormalities in TGFβ signaling pathways and key regulators, such as SMAD4, in the endometrium of affected individuals. We also observed compromised activity of bone morphogenetic proteins (BMP), a subset of the TGFβ family, that control endometrial receptivity. Using 3-dimensional models of endometrial stromal and epithelial assembloids, we showed that exogenous BMP2 improved decidual marker expression in individuals with endometriosis. Our findings reveal dysfunction of BMP/SMAD signaling in the endometrium of individuals with endometriosis, explaining decidualization defects and subsequent pregnancy complications in these individuals. Transcriptomic and genomic studies indicate that disrupted bone morphogenetic protein pathways may be a root cause of flawed endometrial decidualization in individuals with endometriosis. Enhancing these pathways with BMP2 supplementation shows promise in mitigating these defects. [ABSTRACT FROM AUTHOR]

In this issue of Cell Chemical Biology , Lane et al. 1 introduce a transgene-based system to express fusion proteins that recruit transcription factors to E3 ligases. This approach expands the target repertoire for engineered cell therapies as exemplified by the targeting of SMAD proteins to overcome a TGFβ-mediated suppressive mechanism that weakens anti-tumor responses. In this issue of Cell Chemical Biology , Lane et al. introduce a transgene-based system to express fusion proteins that recruit transcription factors to E3 ligases. This approach expands the target repertoire for engineered cell therapies as exemplified by the targeting of SMAD proteins to overcome a TGFβ-mediated suppressive mechanism that weakens anti-tumor responses. [ABSTRACT FROM AUTHOR]

Objective: According to the response-to-retention hypothesis, the inception of atherosclerosis is attributed to the deposition and retention of lipoprotein in the arterial intima, facilitated by altered proteoglycans with hyperelongated glycosaminoglycan (GAG) chains. Recent studies have elucidated a signaling pathway whereby transforming growth factor-β (TGF-β) promotes the expression of genes linked to proteoglycan GAG chain elongation (CHSY1 and CHST11) via reactive oxygen species (ROS) and the downstream phosphorylation of ERK1/2 and Smad2L. Atorvastatin is known to exhibit pleiotropic effects, including antioxidant and anti-inflammatory. The purpose of the present research was to ascertain the influence of atorvastatin on TGF-β-stimulated expression of CHST11 and CHSY1 and associated signaling pathways using an in vitro model. Materials and Methods: In this experimental study, vascular smooth muscle cells (VSMCs) were pre-incubated with atorvastatin (0.1-10 µM) prior to being stimulated with TGF-β (2 ng/ml). The experiment aimed to evaluate the phosphorylation levels of Smad2C, Smad2L, ERK1/2, the NOX p47phox subunit, ROS production, and the mRNA expression of CHST11 and CHSY1. Results: Our research results indicated that atorvastatin inhibited TGF-β-stimulated CHSY1 and CHST11 mRNA expression. Further experiments showed that atorvastatin diminished TGF-β-stimulated ROS production and weakened TGF-β-stimulated phosphorylation of p47phox, ERK1/2, and Smad2L; however, we observed no effect on the TGF-βSmad2C pathway. Conclusion: These data suggest that atorvastatin demonstrates anti-atherogenic properties through the modulation of the ROS-ERK1/2-Smad2L signaling pathway. This provides valuable insight into the potential mechanisms by which atorvastatin exerts its pleiotropic effects against atherosclerosis. [ABSTRACT FROM AUTHOR]

Expression of α‐smooth muscle actin (αSMA) is constitutive in vascular smooth muscle cells, but is induced in nonmuscle cells such as hepatic stellate cells (HSCs). HSCs play important roles in both physiological homeostasis and pathological response. HSC activation is characterized by αSMA expression, which is regulated by the TGFβ‐induced Smad pathway. Recently, protein kinase C (PKC) was identified to regulate αSMA expression. Diacylglycerol kinase (DGK) metabolizes a second‐messenger DG, thereby controlling components of DG‐mediated signaling, such as PKC. In the present study we aimed to investigate the putative role of DGKα in αSMA expression. Use of a cellular model indicated that the DGK inhibitor R59949 promotes αSMA expression and PKCδ phosphorylation. It also facilitates Smad2 phosphorylation after 30 min of TGFβ stimulation. Furthermore, immunocytochemical analysis revealed that DGK inhibitor pretreatment without TGFβ stimulation engenders αSMA expression in a granular pattern, whereas DGK inhibitor pretreatment plus TGFβ stimulation significantly induces αSMA incorporation in stress fibers. Through animal model experiments, we observed that DGKα‐knockout mice exhibit increased expression of αSMA in the liver after 48 h of carbon tetrachloride injection, together with enhanced phosphorylation levels of Smad2 and PKCδ. Together, these findings suggest that DGKα negatively regulates αSMA expression by acting on the Smad and PKCδ signaling pathways, which differentially regulate stress fiber incorporation and protein expression of αSMA, respectively. [ABSTRACT FROM AUTHOR]

Background: Juvenile polyposis syndrome (JPS) is an autosomal dominant, inherited disorder characterized by multiple hyperproliferative polyps of the gastrointestinal tract, particularly of the colon, rectum, and stomach. SMAD4 mutations are frequently associated with multiple polyposis of the stomach; the condition causes severe bleeding and hypoproteinemia, which may progress to severe dysplasia and adenocarcinoma formation. We report our experience with the first case of total gastrectomy with pancreaticoduodenectomy following two partial jejunectomies for JPS, who presented with refractory anemia and protein-losing gastroenteropathy due to polyposis of the stomach and duodenum. Case presentation: A 33-year-old Japanese man presented with the chief complaint of shortness of breath on exertion. His family history included gastric polyposis (mother, aunt, and cousin) and cerebral infarction (grandmother). Blood testing at the initial visit indicated iron-deficiency anemia, whereas endoscopy revealed multiple polyps in the duodenum and jejunum. Genetic testing revealed a 4 bp deletion (TGAA) in exon 5 of the SMAD4 gene; two partial small bowel resections were performed, but polyps grew in the remaining stomach, duodenum, and small intestine. The patient developed hypoalbuminemia and anemia, and required central venous nutrition and blood transfusion. However, because the hyponutrition and anemia remained poorly controlled, a total gastrectomy with concomitant pancreaticoduodenectomy was performed. Malnutrition and anemia improved, and there was no polyp recurrence in the remaining intestinal tract at 18 months after the surgery. Conclusions: We report a case of JPS with refractory anemia and protein-losing gastroenteropathy that was treated with total gastrectomy with concomitant pancreaticoduodenectomy. Although the surgery was highly invasive, the patient's nutritional status and anemia improved postoperatively, and the treatment was successful. However, to determine the appropriate surgical procedure, a detailed examination of the gastrointestinal lesions and the effects of the surgical invasion on nutritional status must be undertaken. [ABSTRACT FROM AUTHOR]