Expression Of Fibrosis-related Genes Research Articles

Harnessing the Power of Non-diabetic Benefits of Metformin Derived from <i>Galega officinalis</i>: Focus on Wound Healing

This review explores the potential of metformin, a widely used type 2 diabetes medication, in accelerating wound healing. Derived from guanidine compounds found in <i>Galega officinalis</i>, a plant with a long history in traditional medicine, metformin has been recognized for its minimal side effects. Beyond its primary role in diabetes treatment, metformin shows promising non-diabetic benefits, particularly in wound healing. Research indicates that metformin enhances wound healing through multiple mechanisms. It increases circulating endothelial progenitor cells, improves vascular function, and regulates thrombospondin-1 levels. Metformin also modulates the AMPK/mTOR/NLRP3 inflammasome signaling pathway, promoting M2 macrophage polarization, which is crucial for tissue repair. Additionally, it reduces pro-inflammatory cytokines, increases growth factors, and decreases matrix metalloproteinases. Studies have shown that topical application of metformin accelerates wound contraction, closure, and overall healing. Furthermore, it has been found to reduce fibrosis-related gene expression and improve collagen synthesis. With chronic wounds affecting millions globally and causing significant healthcare costs, there is a pressing need for improved wound healing agents. This review advocates for further research to establish clinical guidelines on using metformin to enhance wound healing. By harnessing metformin’s pleiotropic effects, healthcare providers may offer personalized treatments that not only manage diabetes but also promote wound healing.

Role of the alarmin S100A9 in the pathogenesis of heart failure with preserved ejection fraction

Abstract Background A systemic low-grade inflammation induced by comorbidities is recognized to underlie heart failure (HF) with preserved ejection fraction (HFpEF)-specific remodelling. Recent evidence states that the innate immunity member S100A9, which is mainly present as the heterodimer S100A8/9, is an important contributor of sterile inflammation in the comorbidities of HFpEF, with adipose tissue being an important source. Though, its specific involvement in HFpEF has not been explored so far. Purpose The present study aimed to unravel the role of S100A9 in the pathogenesis of HFpEF via the two-hit HFpEF mouse model, S100A8/9 stimulation on murine left ventricle (LV) and C4 fibroblasts (Fb) and gene expression analysis of endomyocardial biopsy (EMB)-derived Fb from HFpEF and HF with reduced ejection fraction (HFrEF) patients. Methods Wild type (WT) C57BL/6JN or S100A9 knock-out (ko) mice were exposed to a high-fat diet (HFD) and L-NAME (1 g/L in drinking water) over 15 weeks. Controls received standard diet. LV function was characterized via conductance catheter measurements. At the day of sacrifice, the LV, spleen, blood, and adipose tissue were collected for subsequent analyses. In vitro, murine LV-derived Fb and C4 Fb were stimulated with the heterodimer S100A8/9. EMB-Fb from HFpEF and HFrEF patients were screened for S100A9 and downstream components of the NLRP3 inflammasome. Results WT HFD+L-NAME mice exhibited a preserved EF, combined with a reduced LV relaxation (dP/dtmin; p<0.01), elevated LV relaxation time (Tau; p<0.05), and impaired LV contractility (dP/dtmax; p<0.05), in parallel to a low-grade systemic inflammation evident by increased C-reactive protein levels. S100A9+, CD68+ and Ly6G+ cells, and CD68+ and Ly6G+ cells expressing S100A9 were increased in the LV, spleen and adipose tissue of WT HFD+L-NAME mice compared to WT mice on chow diet. Changes in LV function were less pronounced in S100A9ko HFD+L-NAME mice, which were characterized by lower systemic C-reactive protein levels, and lower presence of CD68+ and Ly6G+ cells in the LV, spleen and adipose tissue versus WT HFD+L-NAME mice, in the absence of S100A9. Moreover, S100A9ko HFD+L-NAME exhibited lower expression of pro-inflammatory and fibrosis-related genes versus WT HFD+L-NAME mice. Stimulation of murine LV-Fb and C4 Fb with S100A8/A9 increased the mRNA expression of the pro-inflammatory chemokines chemokine (C-C motif) ligand (CCL) 2 and CCL7, and the % of NLRP3-, ASC-, caspase 1-, and IL-1ß-expressing cells, respectively. Finally, mRNA expression of S100A9 and components of the NLRP3 inflammasome was higher in EMB-Fb of HFpEF versus HFrEF patients. Conclusion These data support that adipose tissue is an extra-cardiac source of S100A9 contributing to systemic low-grade inflammation. S100A8/9 in the heart can boost the inflammatory potential of cardiac fibroblasts, further supporting the pro-inflammatory role of S100A9 in the pathogenesis of HFpEF development.

Comparing the anti-remodeling effect of sacubitril/valsartan and angiotensin-converting enzyme inhibition on myocardial samples of advanced heart failure patients undergoing heart transplantation

Abstract Background In decreasing heart failure (HF) hospitalization and cardiovascular death in HF patients with reduced ejection fraction, Sacubitril/Valsartan (SAC/VAL) treatment was proved to be superior to angiotensin-converting enzyme inhibition (ACEi). According to recent experimental results and clinical data based on echocardiography and circulating biomarkers, this benefit might be at least partially attributed to a greater anti-remodeling effect. However, there is a lack of direct evidence from human myocardial samples for this assumption. Purpose Therefore, we aimed to compare the anti-remodeling effect of SAC/VAL treatment to ACEi on myocardial samples of HF patients undergoing heart transplantation (HTX). Methods We studied left ventricular (LV) samples of seventy advanced HF patients who underwent HTX and received either SAC/VAL (SAC/VAL group, N=32) or ACEi treatment (ACEi group, N=38) for at least three months prior to HTX. Furthermore, all patients received beta-blockers and mineralocorticoid receptor antagonists titrated to maximally tolerated or target dose. Our groups were matched for age, sex, ejection fraction and other clinical parameters. Patients with liver or kidney failure, mechanical circulatory support, systemic inflammatory/fibrotic diseases or positive inotrope treatment were excluded. Myocardial mRNA expression of fibrotic markers and B-type natriuretic peptide (BNP) were measured with qRT-PCR and normalized to glyceraldehyde 3-phosphate dehydrogenase expression. Interstitial fibrosis area was assessed histologically. Results Preoperative plasma N-terminal pro-BNP levels were similar in the two groups (SAC/VAL: 4363±752 pg/mL vs. ACEi: 4616±1020 pg/mL; p=0.911). In contrast, the mRNA level of BNP in the myocardium was lower in patients treated with SAC/VAL (SAC/VAL: 2.2±1.05 vs. ACEi: 5.2±1.74; p=0.006). TIMP metallopeptidase inhibitor 1 (SAC/VAL: 0.07±0.01 vs. ACEi: 0.13±0.02; p=0.011), TIMP metallopeptidase inhibitor 2 (SAC/VAL: 0.06±0.01 vs. ACEi: 0.11±0.01; p<0.001), collagen type I alpha 1 chain (SAC/VAL: 0.02±0.00 vs. ACEi: 0.08±0.02; p<0.001) and collagen type III alpha 1 chain (SAC/VAL: 0.12±0.02 vs. ACEi: 0.27±0.04; p<0.001) relative gene expressions were also decreased in the LV of SAC/VAL-treated patients. Histology analysis confirmed reduced interstitial myocardial fibrosis area in the SAC/VAL group as well (SAC/VAL: 7.2±0.4% vs. ACEi: 8.6±0.5%; p=0.031). Conclusions SAC/VAL treatment decreased the myocardial expression of BNP and fibrosis-related genes to a greater extent compared with ACEi in LV samples of patients undergoing HTX. Histological analysis also verified the differences in fibrosis. Thus, the anti-remodeling effect of SAC/VAL might be superior to ACEi even in advanced HF.

S-RBD-modified and miR-486-5p-engineered exosomes derived from mesenchymal stem cells suppress ferroptosis and alleviate radiation-induced lung injury and long-term pulmonary fibrosis

BackgroundRadiation-induced lung injury (RILI) is associated with alveolar epithelial cell death and secondary fibrosis in injured lung. Mesenchymal stem cell (MSC)-derived exosomes have regenerative effect against lung injury and the potential to intervene of RILI. However, their intervention efficacy is limited because they lack lung targeting characters and do not carry sufficient specific effectors. SARS-CoV-2 spike glycoprotein (SARS-CoV-2-S-RBD) binds angiotensin-converting enzyme 2 (ACE2) receptor and mediates interaction with host cells. MiR-486-5p is a multifunctional miRNA with angiogenic and antifibrotic potential and acts as an effector in MSC-derived exosomes. Ferroptosis is a form of cell death associated with radiation injury, its roles and mechanisms in RILI remain unclear. In this study, we developed an engineered MSC-derived exosomes with SARS-CoV-2-S-RBD- and miR-486-5p- modification and investigated their intervention effects on RIPF and action mechanisms via suppression of epithelial cell ferroptosis.ResultsAdenovirus-mediated gene modification led to miR-486-5p overexpression in human umbilical cord MSC exosomes (p < 0.05), thereby constructing miR-486-5p engineered MSC exosomes (miR-486-MSC-Exo). MiR-486-MSC-Exo promoted the proliferation and migration of irradiated mouse lung epithelial (MLE-12) cells in vitro and inhibited RILI in vivo (all p < 0.05). MiR-486-MSC-Exo suppressed ferroptosis in MLE-12 cells, and an in vitro assay revealed that the expression of fibrosis-related genes is up-regulated following ferroptosis (both p < 0.05). MiR-486-MSC-Exo reversed the up-regulated expression of fibrosis-related genes induced by TGF-β1 in vitro and improved pathological fibrosis in RIPF mice in vivo (all p < 0.05). SARS-CoV-2-S-RBD-modified and miR-486-5p-engineered MSC exosomes (miR-486-RBD-MSC-Exo) were also constructed, and the distribution of DiR dye-labeled miR-486-RBD-MSC-Exo in hACE2CKI/CKI Sftpc-Cre+ mice demonstrated long-term retention in the lung (p < 0.05). MiR-486-RBD-MSC-Exo significantly improved the survival rate and pathological changes in hACE2CKI/CKI Sftpc-Cre+ RIPF mice (all p < 0.05). Furthermore, miR-486-MSC-Exo exerted anti-fibrotic effects via targeted SMAD2 inhibition and Akt phosphorylation activation (p < 0.05).ConclusionsEngineered MSC exosomes with SARS-CoV-2-S-RBD- and miR-486-5p-modification were developed. MiR-486-RBD-MSC-Exo suppressed ferroptosis and fibrosis of MLE-12 cells in vitro, and alleviated RILI and long-term RIPF in ACE2 humanized mice in vivo. MiR-486-MSC-Exo exerted anti-fibrotic effects via SMAD2 inhibition and Akt activation. This study provides a potential approach for RIPF intervention.Graphical

New peripherally-restricted CB1 receptor antagonists, PMG-505–010 and −013 ameliorate obesity-associated NAFLD and fibrosis

The endocannabinoid system plays a crucial role in metabolic regulation, prompting the investigation of cannabinoid type 1 receptor (CB1R) antagonists for obesity and its complications like non-alcoholic fatty liver disease (NAFLD). Concerns over psychiatric side effects led to the development of peripheral CB1R antagonists that circumvent the blood-brain barrier (BBB). In this study, we synthesized PMG-505–010 and PMG-505–013 as peripherally restricted CB1 receptor antagonists by modifying rimonabant to minimize BBB penetration. Physicochemical analysis confirmed their reduced lipophilicity and increased polarity compared to rimonabant, indicating limited brain exposure. Molecular docking studies revealed similar binding modes to rimonabant at CB1R, characterized by robust hydrophobic interactions. Functionally, they acted as CB1R antagonists and inverse agonists, effectively reversing CP55,940-induced cAMP inhibition. In a murine model of obesity-related NAFLD, PMG-505–010 and −013 improved metabolic profiles, including fasting blood glucose levels and dyslipidemia. They also ameliorated hepatic injury, steatosis, and inflammation, evidenced by reduced liver enzymes, lipid peroxidation, hepatic lipid levels, and inflammatory cytokine levels. Notably, these compounds inhibited hepatic fibrosis by reducing extracellular matrix (ECM) deposition and altering fibrosis-related gene and protein expressions. In conclusion, PMG-505–010 and PMG-505–013 hold promise for treating obesity-related liver diseases, including NAFLD and fibrosis, through selective peripheral CB1R targeting, potentially avoiding CNS-related side effects seen with earlier CB1R antagonists.

IL-21 drives skin and lung inflammation and fibrosis in a model for systemic sclerosis

BackgroundSystemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, abnormal inflammation, and fibrosis of the skin and internal organs, notably the skin and lungs, significantly impairing quality of life. There is currently no cure for SSc, and its etiology remains largely unknown, presenting a primary barrier to effective treatment. We investigated the role of interleukin-21 (IL-21) in the pathogenesis of SSc. MethodsWe assessed the expression levels of fibrosis-related genes in human dermal fibroblasts exposed to IL-21 and TGF beta. We also induced SSc in wild-type C57BL/6 mice and IL-21 knockout (KO) mice with a C57BL/6 background using bleomycin (Bleomycin). Histological analyses were conducted on skin and lung tissues from these mice. The distribution and expression levels of fibrosis-related proteins in the tissues were examined via immunohistochemistry and quantitative real-time PCR. Furthermore, we measured the frequency of Th1, Th2, and Th17 cells among splenocytes through flow cytometry. ResultsIL-21 activation led to STAT3 phosphorylation more than TGF beta in dermal fibroblasts. In IL-21 KO mice with BLM-induced SSc, skin thickness and lung fibrosis were reduced. The absence of IL-21 in these mice resulted in suppressed expression of fibrosis-related genes, including Col1a1, Col1a2, Col3a1, CTGF, α-SMA, STAT3, and TGFβ, in the skin and lungs. It also led to a decreased frequency of Th1, Th2, and Th17 cells, as well as a lower Th17/Treg ratio among splenocytes, factors known to contribute to the development of SSc. ConclusionsIL-21 contributes to the development of SSc by promoting the expression of fibrosis-related genes and modulating the levels of CD4+ T cells.

Core-fucose-specific Pholiota squarrosa lectin decreased hepatic inflammatory macrophage infiltration in steatohepatitis mice.

Recent findings in glycobiology revealed direct evidence of the involvement of oligosaccharide changes in human diseases, including liver diseases. Fucosylation describes the attachment of a fucose residue to a glycan or glycolipid. We demonstrated that fucosylated proteins are useful serum biomarkers for nonalcoholic fatty liver disease. Among fucosyltransferases, expression of alpha-1, 6-fucosyltransferase (Fut8), which produces core fucose, is frequently elevated during the progression of human chronic liver diseases. Previously, we discovered core-fucose-specific Pholiota squarrosa lectin (PhoSL) from Japanese mushroom Sugitake. Lectins are bioactive compounds that bind to glycan specifically, and various kinds of lectin have a variety of biological functions. Using high-fat and high-cholesterol (HFHC)-fed steatohepatitic mice, we found that core fucosylation increases in hepatic inflammatory macrophages. Antibody drugs bind to specific antigens and block protein function. We hypothesized that, like antibody drugs, PhoSL could have inhibitory effects on glycoproteins involved in steatohepatitis progression. PhoSL administration dramatically decreased hepatic macrophage infiltration and liver fibrosis-related gene expression. Using mouse macrophage-like cell RAW264.7, we found that PhoSL enhanced core-fucose-mediated activation of macrophage cell death by blocking interferon-γ/signal transducer and activator of transcription 1 (STAT1) signaling. Core-fucose-mediated cell death is a mechanism for the anti-inflammatory effects and anti-fibrotic effects of PhoSL on activated macrophages in steatohepatitic liver. In addition, PhoSL provides an anti-fibrotic effect by blocking transforming growth factor-β/SMAD family member 3 signaling in hepatic stellate cells. In conclusion, we found core-fucose-specific PhoSL administration could suppress steatohepatitis progression by decreasing inflammatory macrophage infiltration and fibrotic signaling in hepatic stellate cells.

Modulation of liver cholesterol homeostasis by choline supplementation during fibrosis resolution

Liver fibrosis is a critical global health challenge, often leading to severe liver diseases without timely intervention. Choline deficiency has been linked to metabolic dysfunction associated steatohepatitis (MASH) and liver fibrosis, suggesting choline supplementation as a potential therapeutic approach. This study aimed to explore the therapeutic potential of choline supplementation in liver fibrosis resolution and its effects on cholesterol homeostasis using a mouse model with induced liver fibrosis. Our findings reveal that choline supplementation significantly decreases blood lactate dehydrogenase (LDH) and non-high-density lipoprotein cholesterol (non-HDL-C) levels. Transcriptome analysis showed that choline supplementation primarily induces genes related to cholesterol homeostasis, suggesting a significant impact on liver cholesterol synthesis. However, choline supplementation did not significantly alter the expression of fibrosis-related, choline metabolism-related, or epigenetics-related genes. This study provides novel insights into the role of choline in liver health and cholesterol metabolism, potentially informing treatments for liver fibrosis and related conditions.

Photobiomodulation Mitigates PM2.5-Exacerbated Pathologies in a Mouse Model of Allergic Asthma.

Exposure to particulate matter (PM), especially PM2.5, is known to exacerbate asthma, posing a significant public health risk. This study investigated the asthma-reducing effects of photobiomodulation (PBM) in a mice model mimicking allergic airway inflammation exacerbated by PM2.5 exposure. The mice received sensitization with ovalbumin (OVA) and were subsequently treated with PM2.5 at a dose of 0.1 mg/kg every 3 days, for 9 times over 3 weeks during the challenge. PBM, using a 610 nm wavelength LED, was applied at 1.7 mW/cm2 to the respiratory tract via direct skin contact for 20 min daily for 19 days. Results showed that PBM significantly reduced airway hyperresponsiveness, plasma immunoglobulin E (IgE) and OVA-specific IgE, airway inflammation, T-helper type 2 cytokine, histamine and tryptase in bronchoalveolar lavage fluid (BALF), and goblet cell hyperplasia in PM2.5-exposed asthmatic mice. Moreover, PBM alleviated subepithelial fibrosis by reducing collagen deposition, airway smooth muscle mass, and expression of fibrosis-related genes. It mitigated reactive oxygen species generation, oxidative stress, endoplasmic reticulum stress, apoptotic cell death, ferroptosis, and modulated autophagic signals in the asthmatic mice exposed to PM2.5. These findings suggest that PBM could be a promising intervention for PM2.5-induced respiratory complications in patients with allergic asthma.

Cystathionine gamma-lyase deficiency exaggerates diethylnitrosamine-induced liver damage in mice

Cystathionine gamma-lyase (CSE) is a key enzyme in reverse transsulfuration pathway and contributes to the majority of H2S generation in liver tissues via cysteine metabolism. Dysfunction of the CSE/H2S system is linked to both chronic and acute liver damage. This study investigated the regulatory role of CSE deficiency on diethylnitrosamine (DEN)-induced liver damage in mice. A single injection of DEN was administered into 4-week-old male CSE knockout (CSE-KO) mice and wild-type (WT) littermates, and the mice were sacrificed at 28 weeks of age. Compared to age-matched WT mice, CSE-KO mice spontaneously developed steatosis with increased oxidative stress and higher expressions of inflammation and fibrosis-related genes at 28-weeks of age. Following DEN injection, CSE-KO mice experienced more severe liver damage in comparison with the WT group as reflected by elevated levels of lipid accumulation, increased activities of alanine aminotransferase and aspartate aminotransferase, higher oxidative stress and fibrosis development, and increased expressions of inflammation and fibrosis-related genes. No visible tumors were observed in both types of mice with DEN treatment. In addition, the expression levels of the three H2S-generating proteins (CSE, cystathionine beta-synthase, and 3-mercaptopyruvate sulfurtransferase) and the H2S production rate in liver tissues were unaffected by DEN. Taken together, our study demonstrates that CSE provides a significant hepatoprotective effect and deficiency of CSE exaggerates DEN-induced liver damage in mice. Based on these findings, it can be suggested that targeting the CSE/H2S signaling pathway could be a potential therapeutic target for the treatment of liver diseases.

Nuclear receptor 4A1 ameliorates renal fibrosis by inhibiting vascular endothelial growth factor A induced angiogenesis in UUO rats

IntroductionAngiogenesis is closely related to renal fibrosis; however, its basic mechanism remains unclear. In our study, we found that nuclear receptor 4A1 (NR4A1) inhibits vascular endothelial growth factor A (VEGFA)-induced angiogenesis, ameliorating renal fibrosis. MethodsWe prepared a renal fibrosis animal model with unilateral ureteral obstruction (UUO) and NR4A1 knockdown UUO mice model, Using Human umbilical vein endothelial cells (HUVECs) to conduct all in vitro experiments. We then detected and analyzed the expression levels of NR4A1 and other genes related to angiogenesis and fibrosis. ResultsThe angiogenesis related genes, such as VEGFA, vascular endothelial growth factor receptor-2 (VEGFR-2), endoglin (CD105), as well as the expression of fibrosis related genes that included, α-smooth muscle actin (α-SMA), Vimentin, and Collagen I are all significantly increased in the UUO rat model. In addition, the expression of NR4A1 of the kidney tissue of UUO rats was significantly reduced. Therefore, according to the above results, we speculated that angiogenesis may exacerbate renal fibrosis and NR4A1 may repress renal fibrosis by inhibiting angiogenesis. To further verify the above results, we used VEGFA to stimulate HUVECs with (or without) overexpression or knockdown of NR4A1. The results showed that with prolonged stimulation using VEGFA, the expression of NR4A1 decreases. Overexpression of NR4A1 significantly inhibits the expression of related indicators of angiogenesis and renal fibrosis. Furthermore, knockdown of NR4A1 induces endothelial cell proliferation and migration; therefore, exacerbating angiogenesis and fibrosis. Finally, the results of NR4A1 knockdown UUO mice showed that knockdown of NR4A1 can aggravating kidney damage and induce the expression of angiogenesis and renal fibrosis related indicators, while UUO can significantly induce kidney damage, angiogenesis and renal fibrosis. When knockdown of NR4A1, renal kidney damage, angiogenesis and fibrosis becomes more severe than UUO. Thus, all of these results indicate that NR4A1 can ameliorate renal fibrosis by inhibiting angiogenesis. ConclusionsNR4A1 can inhibit angiogenesis to ameliorate renal fibrosis.

Evaluation of the expression of fibrosis-related genes as non-invasive diagnostic biomarkers for cirrhotic HCV-infected patients

Liver cirrhosis is a condition with high mortality that poses a significant health and economic burden worldwide. The clinical characteristics of liver cirrhosis are complex and varied. Therefore, the evaluation of immune infiltration-involved genes incirrhosis has become mandatory in liver disease research, not only to identify the potential biomarkers but also to provide important insights into the underlying mechanisms of the disease. In this study, we aimed to investigate the expression profile of cytokine genes in peripheral blood mononuclear cells (PBMCs) of HCV patients and identify the gene expression signature associated with advanced cirrhosis. A cross-sectional study of 90 HCV genotype 4 patients, including no fibrosis patients (F0, n = 24), fibrotic patients (F1-F3, n = 36), and cirrhotic patients (F4, n = 30) has been conducted. The expression of cytokine genes was analyzed by quantitative real-time PCR in the subjects’ PBMCs, and the serum level of TGFβ2 was measured by ELISA. Our findings showed that the expression level of the TGIF1 transcript was lower in cirrhotic and fibrotic patients compared to no fibrosis patients (p = 0.046 and 0.022, respectively). Also, there was an upregulation of the TGFβ1 gene in cirrhotic patients relative to fibrotic patients (p = 0.015). Additionally, the cirrhotic patients had higher expression levels of the TGF-β2 transcript and elevated levels of the TGF-β2 protein than patients with no cirrhosis or fibrosis. According to the ROC analysis, TGFβ1, TGIF1 transcripts, and TGFβ2 protein have a good discriminatory performance in distinguishing between cirrhotic, fibrotic, and non-fibrotic patients. Our results suggested that the expression of TGIF1, TGF-β1, and TGF-β2 genes in PBMCs may provide a valuable tool for identifying patients with advanced cirrhosis and that TGF-β and TGIF1 may be potential biomarkers for cirrhosis. These findings may have implications for the diagnosis and treatment of cirrhosis in HCV patients.

Carbon monoxide attenuates cellular senescence-mediated pulmonary fibrosis via modulating p53/PAI-1 pathway

PurposeIdiopathic pulmonary fibrosis (IPF) is a fatal progressive condition often requiring lung transplantation. Accelerated senescence of type II alveolar epithelial cells (AECII) plays a crucial role in pulmonary fibrosis progression through the secretion of the senescence-associated secretory phenotype (SASP). Low-dose carbon monoxide (CO) possesses anti-inflammatory, anti-oxidative, and anti-aging properties. This study aims to explore the preventive effects of CO-releasing molecule 2 (CORM2) in a bleomycin-induced pulmonary fibrosis model. MethodsWe established an pulmonary fibrosis model in C57BL/6J mice and evaluated the impact of CORM2 on fibrosis pathology using Masson's trichrome staining, fluorescence staining, and pulmonary function tests. Fibrogenic marker expression and SASP secretion in tissues and AECII cells were analyzed using qRT-PCR, Western blot, and ELISA assays both in vivo and in vitro. Additionally, we investigated DNA damage and cellular senescence through immunofluorescence and SA-β-gal staining. ResultsCORM2 showed a preventive effect on bleomycin-induced lung fibrosis by improving pulmonary function and reducing the expression of fibrosis-related genes, such as TGF-β, α-SMA, Collagen I/III. CORM2 decreased the DNA damage response by inhibiting γ-H2AX, p53, and p21. We identified PAI-1 as a new target gene that was downregulated by CORM2, and which was associated with cellular senescence and fibrosis. CORM2 effectively inhibited cellular senescence and delayed EMT occurrence in AECII cells. ConclusionOur study highlights the potential of CORM2 in preventing DNA damage-induced cellular senescence in bleomycin-induced pulmonary fibrosis through modulation of the p53/PAI-1 signaling pathway. These findings underscore the promising prospects of CORM2 in targeting cellular senescence and the p53/PAI-1 pathway as a potential preventive strategy for IPF.

MicroRNA-26a deficiency attenuates the severity of frozen shoulder in a mouse immobilization model.

The main pathogenesis of the frozen shoulder is thought to be the inflammation of the intra-articular synovium and subsequent fibrosis of the shoulder joint capsule. However, the molecular pathogenesis of the frozen shoulder is still unknown. A class of noncoding RNAs, microRNAs contribute to various diseases including musculoskeletal diseases. MicroRNA-26a (miR-26a) has been reported to be associated with fibrosis in several organs. This study aims to reveal the role of miR-26a on fibrosis in the shoulder capsule using a frozen shoulder model in miR-26a deficient (miR-26a KO) mice. MiR-26a KO and wild-type (WT) mice were investigated using a frozen shoulder model. The range of motion (ROM) of the shoulder, histopathological changes such as synovitis, and fibrosis-related gene expression in the model mice were evaluated to determine the role of miR-26a. In WT mice, both inflammatory cell infiltration and thickening of the inferior shoulder joint capsule were observed after 1 week of immobilization, and this thickening further progressed over the subsequent 6 weeks. However, the immobilized shoulder in miR-26a KO mice consistently exhibited significantly better ROM compared with WT mice at 1 and 6 weeks, and histological changes were significantly less severe. The expression of inflammation- and fibrosis-related genes was decreased in the miR-26a KO mice compared with WT mice at 1 and 6 weeks. Together, miR-26a deficiency attenuated the severity of frozen shoulder in the immobilization model mouse. The present study suggests that miR-26a has the potential to be a target miRNA for therapeutic approach to frozen shoulder.

Macrophage iron dyshomeostasis promotes aging-related renal fibrosis.

Renal aging, marked by the accumulation of senescent cells and chronic low-grade inflammation, leads to renal interstitial fibrosis and impaired function. In this study, we investigate the role of macrophages, a key regulator of inflammation, in renal aging by analyzing kidney single-cell RNA sequencing data of C57BL/6J mice from 8 weeks to 24 months. Our findings elucidate the dynamic changes in the proportion of kidney cell types during renal aging and reveal that increased macrophage infiltration contributes to chronic low-grade inflammation, with these macrophages exhibiting senescence and activation of ferroptosis signaling. CellChat analysis indicates enhanced communications between macrophages and tubular cells during aging. Suppressing ferroptosis alleviates macrophage-mediated tubular partial epithelial-mesenchymal transition invitro, thereby mitigating the expression of fibrosis-related genes. Using SCENIC analysis, we infer Stat1 as a key age-related transcription factor promoting iron dyshomeostasis and ferroptosis in macrophages by regulating the expression of Pcbp1, an iron chaperone protein that inhibits ferroptosis. Furthermore, through virtual screening and molecular docking from a library of anti-aging compounds, we construct a docking model targeting Pcbp1, which indicates that the natural small molecule compound Rutin can suppress macrophage senescence and ferroptosis by preserving Pcbp1. In summary, our study underscores the crucial role of macrophage iron dyshomeostasis and ferroptosis in renal aging. Our results also suggest Pcbp1 as an intervention target in aging-related renal fibrosis and highlight Rutin as a potential therapeutic agent in mitigating age-related renal chronic low-grade inflammation and fibrosis.

Left atrial reservoir strain is a marker of atrial fibrotic remodeling in patients undergoing cardiovascular surgery: Analysis of gene expression.

Left atrial strain (LAS) measured by two-dimensional speckle tracking echocardiography (2DSTE) is considered to be a marker of LA structural remodeling, but it remains unsettled. We investigated the potential usefulness and clinical relevance of LAS to detect atrial remodeling including fibrosis by analyzing gene expression in cardiovascular surgery patients. Preoperative 2DSTE was performed in 131 patients (92 patients with sinus rhythm [SR] patients including paroxysmal AF [PAF], 39 atrial fibrillation [AF]) undergoing cardiovascular surgery. Atrial samples were obtained from the left atrial appendages, and mRNA expression level was analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) in 59 cases (24 PAF, 35 AF). Mean value of left atrial reservoir strain (mLASr) correlated with left atrial volume index (LAVI), and left atrial conduit strain (mLAScd). mLASr also correlated with left atrial contractile strain (mLASct) in SR patients including PAF. mLASr was significantly lower, and LAVI was higher, in the AF group, compared with SR patients including PAF. The expression of COL1A1 mRNA encoding collagen type I α1 significantly increased in AF patients (p = 0.031). mLASr negatively correlated with COL1A1 expression level, and multivariate regression analysis showed that mLASr was an independent predictor of atrial COL1A1 expression level, even after adjusting for age, sex, and BMI. But, neither mLAScd / mLASct nor LAVI (bp) correlated with COL1A1 gene expression. The expression level of COL1A1 mRNA strongly correlated with ECM-related genes (COL3A1, FN1). It also correlated ECM degradation-related genes (MMP2, TIMP1, and TIMP2), pro-fibrogenic cytokines (TGFB1 encoding TGFβ1, END1, PDGFD, CTGF), oxidant stress-related genes (NOX2, NOX4), ACE, inflammation-related genes (NLRP, IL1B, MCP-1), and apoptosis (BAX). Among the fibrosis-related genes examined, univariable regression analysis showed that log (COL1A1) was associated with log (TGFB1) (adjusted R2 = 0.685, p<0.001), log (NOX4) (adjusted R2 = 0.622, p<0.001), log (NOX2) (adjusted R2 = 0.611, p<0.001), suggesting that TGFB1 and NOX4 was the potent independent determinants of COL1A1 expression level. mLASr negatively correlated with the ECM-related genes, and fibrosis-related gene expression level including TGFB1, NOX2, and NLRP3 in PAF patients. PAF patients with low mLASr had higher expression of the fibrosis-related gene expression, compared with those with high mLASr. These results suggest that LASr correlates with atrial COL1A1 gene expression associated with fibrosis-related gene expression. Patients with low LASr exhibit increased atrial fibrosis-related gene expression, even those with PAF, highlighting the utility of LAS as a marker for LA fibrosis in cardiovascular surgery patients.

Effects of metformin on knee joint capsule fibrosis in a diabetic mouse model.

The antidiabetic agent metformin inhibits fibrosis in various organs. This study aims to elucidate the effects of hyperglycaemia and metformin on knee joint capsule fibrosis in mice. Eight-week-old wild-type (WT) and type 2 diabetic (db/db) mice were divided into four groups without or with metformin treatment (WT met(-/+), Db met(-/+)). Mice received daily intraperitoneal administration of metformin and were killed at 12 and 14 weeks of age. Fibrosis morphology and its related genes and proteins were evaluated. Fibroblasts were extracted from the capsules of 14-week-old mice, and the expression of fibrosis-related genes in response to glucose and metformin was evaluated in vitro. The expression of all fibrosis-related genes was higher in Db met(-) than in WT met(-) and was suppressed by metformin. Increased levels of fibrosis-related genes, posterior capsule thickness, and collagen density were observed in the capsules of db/db mice compared with those in WT mice; these effects were suppressed by metformin. Glucose addition increased fibrosis-related gene expression in both groups of mice in vitro. When glucose was added, metformin inhibited the expression of fibrosis-related genes other than cellular communication network factor 2 (Ccn2) in WT mouse cells. Hyperglycaemia promotes fibrosis in the mouse knee joint capsule, which is inhibited by metformin. These findings can help inform the development of novel strategies for treating knee joint capsule fibrosis.

Addition of Polyphenols to Drugs: The Potential of Controlling "Inflammaging" and Fibrosis in Human Senescent Lung Fibroblasts In Vitro.

The combination of a polyphenol, quercetin, with dasatinib initiated clinical trials to evaluate the safety and efficacy of senolytics in idiopathic pulmonary fibrosis, a lung disease associated with the presence of senescent cells. Another approach to senotherapeutics consists of controlling inflammation related to cellular senescence or "inflammaging", which participates, among other processes, in establishing pulmonary fibrosis. We evaluate whether polyphenols such as caffeic acid, chlorogenic acid, epicatechin, gallic acid, quercetin, or resveratrol combined with different senotherapeutics such as metformin or rapamycin, and antifibrotic drugs such as nintedanib or pirfenidone, could present beneficial actions in an in vitro model of senescent MRC-5 lung fibroblasts. A senescent-associated secretory phenotype (SASP) was evaluated by the measurement of interleukin (IL)-6, IL-8, and IL-1β. The senescent-associated β-galactosidase (SA-β-gal) activity and cellular proliferation were assessed. Fibrosis was evaluated using a Picrosirius red assay and the gene expression of fibrosis-related genes. Epithelial-mesenchymal transition (EMT) was assayed in the A549 cell line exposed to Transforming Growth Factor (TGF)-β in vitro. The combination that demonstrated the best results was metformin and caffeic acid, by inhibiting IL-6 and IL-8 in senescent MRC-5 cells. Metformin and caffeic acid also restore cellular proliferation and reduce SA-β-gal activity during senescence induction. The collagen production by senescent MRC-5 cells was inhibited by epicatechin alone or combined with drugs. Epicatechin and nintedanib were able to control EMT in A549 cells. In conclusion, caffeic acid and epicatechin can potentially increase the effectiveness of senotherapeutic drugs in controlling lung diseases whose pathophysiological component is the presence of senescent cells and fibrosis.

Novel Small-Molecule ROCK2 Inhibitor GNS-3595 Attenuates Pulmonary Fibrosis in Preclinical Studies.

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease that leads to respiratory decline caused by scarring and thickening of lung tissues. Multiple pathways contribute to the fibrotic process in this disease, such as inflammation, epithelial-to-mesenchymal transition, and oxidative stress. The Rho-associated coiled-coil forming protein kinase (ROCK) signaling pathway is a key regulator of profibrotic signaling, as it affects the organization of actin-myosin and the remodeling of the extracellular matrix. ROCK1/2, a downstream effector of RhoA, is overexpressed in patients with IPF and is a promising target for IPF therapy. However, because of the hypotensive side effects of ROCK1/2 inhibitors, selective ROCK2 compounds are being explored. In this study, we report the discovery of GNS-3595, a potent and selective ROCK2 inhibitor that has ∼80-fold selectivity over ROCK1 at physiological concentrations of ATP. GNS-3595 effectively inhibited ROCK2-mediated phosphorylation of myosin light chain and reduced the expression of fibrosis-related proteins (e.g., collagen, fibronectin, and α-smooth muscle actin) in various invitro cellular models. GNS-3595 also prevented transforming growth factor β-induced fibroblast-to-myofibroblast transition. In addition, in a bleomycin-induced mouse model of pulmonary fibrosis, therapeutic exposure to GNS-3595, suppressed lung fibrosis, stabilized body weight loss, and prevented fibrosis-induced lung weight gain. Transcriptome and protein expression analysis from lung tissues showed that GNS-3595 can revert the fibrosis-related gene expression induced by bleomycin. These results indicate that GNS-3595 is a highly potent, selective, and orally active ROCK2 inhibitor with promising therapeutic efficacy against pulmonary fibrosis.

Hepatitis C virus NS5A and core protein induce fibrosis-related genes regulation on Huh7 cells through activation of LX2 cells

Introduction and ObjectivesLiver fibrosis remains a complication derived from a chronic Hepatitis C Virus (HCV) infection even when it is resolved, and no liver antifibrotic drug has been approved. Molecular mechanisms on hepatocytes and activation of hepatic stellate cells (HSCs) play a central role in liver fibrogenesis. To elucidate molecular mechanisms, it is important to analyze pathway regulation during HSC activation and HCV infection. Materials and MethodsWe evaluate the fibrosis-associated molecular mechanisms during a co-culture of human HSCs (LX2), with human hepatocytes (Huh7) that express HCV NS5A or Core protein. We evaluated LX2 activation induced by HCV NS5A or Core expression in Huh7 cells during co-culture. We determined a fibrosis-associated gene expression profile in Huh7 that expresses NS5A or Core proteins during the co-culture with LX2. ResultsWe observed that NS5A induced 8.3-, 6.7- and 4-fold changes and that Core induced 6.5-, 1.8-, and 6.2-fold changes in the collagen1, TGFβ1, and timp1 gene expression, respectively, in LX2 co-cultured with transfected Huh7. In addition, NS5A induced the expression of 30 genes while Core induced 41 genes and reduced the expression of 30 genes related to fibrosis in Huh7 cells during the co-culture with LX2, compared to control. The molecular pathways enriched from the gene expression profile were involved in TGFB signaling and the organization of extracellular matrix. ConclusionsWe demonstrated that HCV NS5A and Core protein expression regulate LX2 activation. NS5A and Core-induced LX2 activation, in turn, regulates diverse fibrosis-related gene expression at different levels in Huh7, which can be further analyzed as potential antifibrotic targets during HCV infection.