Lipid nephrotoxicity mediated by HIF-1α activation accelerates tubular injury in diabetic nephropathy

This study is intended to explore the effect of hypoxia-inducible factor-1α (HIF-1α) activation on lipid accumulation in the diabetic kidney. A type 1 diabetic rat model was established by STZ intraperitoneal injection. Cobalt chloride (CoCl2) and YC-1 were used as the HIF-1α activator and antagonist, respectively. CoCl2 treatment significantly increased HIF-1α expression, accelerated lipid deposition, and accelerated tubular injury in diabetic kidneys. In vitro, CoCl2 effectively stabilized HIF-1α and increased its transportation from the cytoplasm to the nucleus, which was accompanied by significantly increased lipid accumulation in HK-2 cells. Furthermore, results obtained in vivo showed that HIF-1α protein expression in the renal tubules of diabetic rats was significantly downregulated by YC-1 treatment. Meanwhile, lipid accumulation in the tubules of the DM + YC-1 group was markedly decreased in comparison to the DM + DMSO group. Accordingly, PAS staining revealed that the pathological injury caused to the tubular epithelial cells was alleviated by YC-1 treatment. Furthermore, the blood glucose level, urine albumin creatinine ratio, and NAG creatinine ratio in the DM + YC-1 group were significantly decreased compared to the DM + DMSO group. Moreover, the protein expression levels of transforming growth factor β1 (TGF-β1) and connective tissue growth factor (CTGF) in diabetic kidneys were decreased by YC-1 treatment. Our findings demonstrate that the activation of HIF-1α contributed to interstitial injury in a rat model of diabetic nephropathy and that the underlying mechanism involved the induction of lipid accumulation.

Caffeic acid phenethyl ester restores mitochondrial homeostasis against peritoneal fibrosis induced by peritoneal dialysis through the AMPK/SIRT1 pathway

Increasing evidence suggests that peritoneal fibrosis induced by peritoneal dialysis (PD) is linked to oxidative stress. However, there are currently no effective interventions for peritoneal fibrosis. In the present study, we explored whether adding caffeic acid phenethyl ester (CAPE) to peritoneal dialysis fluid (PDF) improved peritoneal fibrosis caused by PD and explored the molecular mechanism. We established a peritoneal fibrosis model in Sprague-Dawley rats through intraperitoneal injection of PDF and lipopolysaccharide (LPS). Rats in the PD group showed increased peritoneal thickness, submesothelial collagen deposition, and the expression of TGFβ1 and α-SMA. Adding CAPE to PDF significantly inhibited PD-induced submesothelial thickening, reduced TGFβ1 and α-SMA expression, alleviated peritoneal fibrosis, and improved the peritoneal ultrafiltration function. In vitro, peritoneal mesothelial cells (PMCs) treated with PDF showed inhibition of the AMPK/SIRT1 pathway, mitochondrial membrane potential depolarization, overproduction of mitochondrial reactive oxygen species (ROS), decreased ATP synthesis, and induction of mesothelial-mesenchymal transition (MMT). CAPE activated the AMPK/SIRT1 pathway, thereby inhibiting mitochondrial membrane potential depolarization, reducing mitochondrial ROS generation, and maintaining ATP synthesis. However, the beneficial effects of CAPE were counteracted by an AMPK inhibitor and siSIRT1. Our results suggest that CAPE maintains mitochondrial homeostasis by upregulating the AMPK/SIRT1 pathway, which alleviates oxidative stress and MMT, thereby mitigating the damage to the peritoneal structure and function caused by PD. These findings suggest that adding CAPE to PDF may prevent and treat peritoneal fibrosis.

M2 macrophages promote subconjunctival fibrosis through YAP/TAZ signalling

PURPOSE

To evaluate the role of M2 macrophages in subconjunctival fibrosis after silicone implantation (SI) and investigate the underlying mechanisms.

MATERIALS AND METHODS

A model of subconjunctival fibrosis was established by SI surgery in rabbit eyes. M2 distribution and collagen deposition were evaluated by histopathology. The effects of M2 cells on the migration (using wound-scratch assay) and activation (by immunofluorescence and western blotting) of human Tenon's fibroblasts (HTFs) were investigated.

RESULTS

There were more M2 macrophages (CD68+/CD206+ cells) occurring in tissue samples around silicone implant at 2 weeks postoperatively. Dense collagen deposition was observed at 8 weeks after SI. In vitro experiment showed M2 expressed high level of CD206 and transforming growth factor-β1 (TGF-β1). The M2-conditioned medium promoted HTFs migration and the synthesis of collagen I and fibronectin. Meanwhile, M2-conditioned medium increased the protein levels of TGF-β1, TGF-βR II, p-Smad2/3, yes-associated protein (YAP), and transcriptional coactivator with PDZ-binding motif (TAZ). Verteporfin, a YAP inhibitor, suppressedTGF-β1/Smad2/3-YAP/TAZ pathway and attenuated M2-induced extracellular matrix deposition by HTFs.

CONCLUSIONS

TGF-β1/Smad2/3-YAP/TAZ signalling may be involved in M2-induced fibrotic activities in HTFs. M2 plays a key role in promoting subconjunctival fibrosis and can serve as an attractive target for anti-fibrotic therapeutics.

RfxCas13d-mediated inhibition of Circ1647 alleviates renal fibrosis via PI3K/AKT signaling pathway

BACKGROUND

Circular RNAs (CircRNAs) have been shown to be involved in the development of chronic kidney disease (CKD). This study aimed to investigate the role of Circ1647 in renal fibrosis, which is a hallmark of CKD.

METHODS

In this study, we established a unilateral ureteral obstruction (UUO) model and delivered Circ1647 RfxCas13d knockdown plasmid into renal parenchymal cells via retrograde injection through the ureter followed by electroporation. After that, the pathological changes were determined by Hematoxylin and Eosin. Meanwhile, Immunohistochemistry, qRT-PCR and Western blot were conducted to assess the degree of fibrosis. In addition, overexpressing of Circ1647 in renal tubular epithelial cells (TCMK1) was performed to investigate the underlying mechanisms of Circ1647.

RESULTS

Our results displayed that electroporation-mediated knockdown of Circ1647 by RfxCas13d knockdown plasmid significantly inhibited renal fibrosis in UUO mice as evidenced by reduced expression of fibronectin and α-SMA (alpha-smooth muscle actin). Conversely, overexpression of Circ1647 in TCMK1 cells promoted the fibrosis. In terms of mechanism, Circ1647 may mediate the PI3K/AKT Signaling Pathway as demonstrated by the balance of the phosphorylation of PI3K and AKT in vivo and the aggravated phosphorylation of PI3K and AKT in vitro. These observations were corroborated by the effects of the PI3K inhibitor LY294002, which mitigated fibrosis post Circ1647 overexpression.

CONCLUSION

Our study suggests that Circ1647 plays a significant role in renal fibrosis by mediating the PI3K/AKT signaling pathway. RfxCas13d-mediated inhibition of Circ1647 may serve as a therapeutic target for renal fibrosis in CKD.

Maternal malnutrition associated with postnatal sugar consumption increases inflammatory response and prostate disorders in rat offspring

Maternal malnutrition can alter developmental biology, programming health and disease in offspring. The increase in sugar consumption during the peripubertal period, a worldwide concern, also affects health through adulthood. Studies have shown that maternal exposure to a low protein diet (LPD) is associated with an increase in prostate disease with aging. However, the combined effects of maternal LPD and early postnatal sugar consumption on offspring prostate disorders were not investigated. The effects on aging were evaluated using a maternal gestational model with lactational LPD (6% protein) and sugar consumption (10%) from postnatal day (PND) 21-90, associating the consequences on ventral prostate (VP) rats morphophysiology on PND540. An increase was shown in mast cells and in the VP of the CTR + SUG and Gestational and Lactational Low Protein (GLLP) groups. In GLLP + SUG, a significant increase was shown in TGF-β1 expression in both the systemic and intra-prostatic forms, and SMAD2/3p had increased. The study identified maternal LPD and sugar consumption as risk factors for prostatic homeostasis in senility, activating the TGFβ1-SMAD2/3 pathway, a signaling pathway with potential markers for prostatic disorders.

Suspended particulate matter promotes epithelial-to-mesenchymal transition in alveolar epithelial cells via TGF-β1-mediated ROS/IL-8/SMAD3 axis

Epidemiological evidence presents that dust storms are related to respiratory diseases, such as pulmonary fibrosis (PF). However, the precise underlying mechanisms of SPM-elicited adverse effects still need to be investigated. Epithelial-mesenchymal transition (EMT) process is a characteristic of PF. We discussed whether suspended particulate matter (SPM) is involved in EMT induction via transforming growth factor-β1 (TGF-β1). In this study, a detailed elemental analysis (55 elements), particle size, and morphology were determined. To investigate the toxicity of SPM, an MTT test was performed to detect cell viability. Next, A549 cells were exposed to selected concentrations of SPM (20 and 40 µg/mL) for single and repeated exposures. The DCFH-DA assay showed that exposure to SPM could produce reactive oxygen species (ROS). The ELISA assay demonstrated increased levels of interleukin-8 (IL-8) and TGF-β1 in the supernatant. Western blot was used to detect the expression of proteins associated with EMT and the SMAD3-dependent pathway. Results of western blot demonstrated that E-cadherin was reduced, whereas p-SMAD3, vimentin, and α-smooth muscle actin were elevated. Our findings indicated that SPM triggered EMT by induction of oxidative stress, inflammation, and the TGF-β1/SMAD3 pathway activation.

Exosomes from adipose-derived mesenchymal stem cell improve diabetic wound healing and inhibit fibrosis via miR-128-1-5p/TGF-β1/Smad axis

OBJECTIVE

Difficult-to-heal wound is a prevalent and significant complication of diabetes, characterized by impaired functionality of epithelial cells such as fibroblasts. This study aims to investigate the potential mechanism of ADSC-Exos promoting diabetic wound healing by regulating fibroblast function.

MATERIALS AND METHODS

ADSC-Exos were confirmed through TEM, NTA, and Western Blot techniques. The study conducted on rat skin fibroblasts (RSFs) exposed to 33 mmol/L glucose in vitro. We used cck-8, EDU, transwell, and scratch assays to verify the proliferation and migration of RSFs. Furthermore, levels of TGF-β1 and α-SMA proteins were determined by immunofluorescence and Western Blot. RSFs were transfected with miR-128-1-5p mimics and inhibitors, followed by quantification of TGF-β1, α-SMA, Col I and Smad2/3 protein levels using Western Blot. In vivo, the effects of ADSC-Exos on diabetic wounds were assessed using digital imaging, histological staining, as well as Western Blot analysis.

RESULTS

In vitro, ADSC-Exos significantly enhanced proliferation and migration of RSFs while reducing the expression of TGF-β1 and α-SMA. In vivo, ADSC-Exos effectively promoted diabetic wound healing and mitigated scar fibrosis. Additionally, ADSC-Exos exhibited elevated levels of miR-128-1-5p, which targets TGF-β1, resulting in a notable reduction in TGF-β1, α-SMA, Col I and smad2/3 phosphorylation in RSFs.

CONCLUSION

In conclusion, our results demonstrated that ADSC-Exos promoted diabetic wound healing, and inhibited skin fibrosis by regulating miR-128-1-5p/TGF-β1/Smad signaling pathway, which provides a promising innovative treatment for diabetic wound healing.

Identification of anti-fibrotic and pro-apoptotic bioactive compounds from Ganoderma formosanum and their possible mechanisms in modulating TGF-β1-induced lung fibrosis

ETHNOPHARMACOLOGICAL RELEVANCE

The Compendium of Materia Medica and the Classic of Materia Medica, the two most prominent records of traditional Chinese medicine, documented the therapeutic benefits of Ganoderma sinense particularly in addressing pulmonary-related ailments. Ganoderma formosanum, an indigenous subspecies of G. sinense from Taiwan, has demonstrated the same therapeutic properties.

AIM OF THE STUDY

The aim of this study is to identify bioactive compounds and evaluate the potential of G. formosanum extracts as a novel treatment to alleviate pulmonary fibrosis (PF). Using an in-house drug screening platform, two-stage screening was performed to determine their anti-fibrotic efficacy.

METHODS AND MATERIALS

G. formosanum was fractionated into four partitions by solvents of different polarities. To determine their antifibrotic and pro-apoptotic properties, the fractions were analyzed using two TGF-β1-induced pulmonary fibrosis cell models (NIH-3T3) and human pulmonary fibroblast cell lines, immunoblot, qRT-PCR, and annexin V assays. Subsequently, transcriptomic analysis was conducted to validate the findings and explore possible molecular pathways. The identification of potential bioactive compounds was achieved through UHPLC-MS/MS analysis, while molecular interaction study was investigated by multiple ligands docking and molecular dynamic simulations.

RESULTS

The ethyl acetate fraction (EAF) extracted from G. formosanum demonstrated substantial anti-fibrotic and pro-apoptotic effects on TGF-β1-induced fibrotic models. Moreover, the EAF exhibited no discernible cytotoxicity. Untargeted UHPLC-MS/MS analysis identified potential bioactive compounds in EAF, including stearic acid, palmitic acid, and pentadecanoic acid. Multiple ligands docking and molecular dynamic simulations further confirmed that those bioactive compounds possess the ability to inhibit TGF-β receptor 1.

CONCLUSION

Potential bioactive compounds in G. formosanum were successfully extracted and identified in the EAF, whose anti-fibrotic and pro-apoptotic properties could potentially modulate pulmonary fibrosis. This finding not only highlights the EAF's potential as a promising therapeutic candidate to treat pulmonary fibrosis, but it also elucidates how Ganoderma confers pulmonary health benefits as described in the ancient texts.

Yinchen gongying decoction mitigates CCl4-induced chronic liver injury and fibrosis in mice implicated in inhibition of the FoxO1/TGF-β1/ Smad2/3 and YAP signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Liver fibrosis (LF) is a common reversible consequence of chronic liver damage with limited therapeutic options. Yinchen Gongying decoction (YGD) composed of two homologous plants: (Artemisia capillaris Thunb, Taraxacum monochlamydeum Hand.-Mazz.), has a traditionally application as a medicinal diet for acute icteric hepatitis. However, its impact on LF and underlying mechanisms remain unclear.

AIM OF THE STUDY

This study aims to assess the impact of YGD on a carbon tetrachloride (CCl4) induced liver fibrosis and elucidate its possible mechanisms. The study seeks to establish an experimental foundation for YGD as a candidate drug for hepatic fibrosis.

MATERIALS AND METHODS

LC-MS/MS identified 11 blood-entry components in YGD, and network pharmacology predicted their involvement in the FoxO signaling pathway, insulin resistance, and PI3K-AKT signaling pathway. Using a CCl4-induced LF mouse model, YGD's protective effects were evaluated in comparison to a positive control and a normal group. The underlying mechanisms were explored through the assessments of hepatic stellate cells (HSCs) activation, fibrotic signaling, and inflammation.

RESULTS

YGD treatment significantly improved liver function, enhanced liver morphology, and reduced liver collagen deposition in CCl4-induced LF mice. Mechanistically, YGD inhibited HSC activation, elevated MMPs/TIMP1 ratios, suppressed the FoxO1/TGF-β1/Smad2/3 and YAP pathways, and exhibited anti-inflammatory and antioxidant effects. Notably, YGD improved the insulin signaling pathway.

CONCLUSION

YGD mitigates LF in mice by modulating fibrotic and inflammatory pathways, enhancing antioxidant responses, and specifically inhibiting FoxO1/TGF-β1/Smad2/3 and YAP signal pathways.

Primary Mouse Aortic Smooth Muscle Cells Exhibit Region- and Sex-Dependent Biological Responses In Vitro

Despite advancements in elucidating biological mechanisms of cardiovascular remodeling, cardiovascular disease (CVD) remains the leading cause of death worldwide. When stratified by sex, clear differences in CVD prevalence and mortality between males and females emerge. Regional differences in phenotype and biological response of cardiovascular cells are important for localizing the initiation and progression of CVD. Thus, to better understand region and sex differences in CVD presentation, we have focused on characterizing in vitro behaviors of primary vascular smooth muscle cells (VSMCs) from the thoracic and abdominal aorta of male and female mice. VSMC contractility was assessed by traction force microscopy (TFM; single cell) and collagen gel contraction (collective) with and without stimulation by transforming growth factor-beta 1 (TGF-β1) and cell proliferation was assessed by a colorimetric metabolic assay (MTT). Gene expression and TFM analysis revealed region- and sex-dependent behaviors, whereas collagen gel contraction was consistent across sex and aortic region under baseline conditions. Thoracic VSMCs showed a sex-dependent sensitivity to TGF-β1-induced collagen gel contraction (female > male; p = 0.025) and a sex-dependent proliferative response (female > male; p < 0.001) that was not apparent in abdominal VSMCs. Although primary VSMCs exhibit intrinsic region and sex differences in biological responses that may be relevant for CVD presentation, several factors-such as inflammation and sex hormones-were not included in this study. Such factors should be included in future studies of in vitro mechanobiological responses relevant to CVD differences in males and females.

Exploring the impact of the PNPLA3 I148M variant on primary human hepatic stellate cells using 3D extracellular matrix models

BACKGROUND & AIMS

The PNPLA3 rs738409 C>G (encoding for I148M) variant is a risk locus for the fibrogenic progression of chronic liver diseases, a process driven by hepatic stellate cells (HSCs). We investigated how the PNPLA3 I148M variant affects HSC biology using transcriptomic data and validated findings in 3D-culture models.

METHODS

RNA sequencing was performed on 2D-cultured primary human HSCs and liver biopsies of individuals with obesity, genotyped for the PNPLA3 I148M variant. Data were validated in wild-type (WT) or PNPLA3 I148M variant-carrying HSCs cultured on 3D extracellular matrix (ECM) scaffolds from human healthy and cirrhotic livers, with/without TGFB1 or cytosporone B (Csn-B) treatment.

RESULTS

Transcriptomic analyses of liver biopsies and HSCs highlighted shared PNPLA3 I148M-driven dysregulated pathways related to mitochondrial function, antioxidant response, ECM remodelling and TGFB1 signalling. Analogous pathways were dysregulated in WT/PNPLA3-I148M HSCs cultured in 3D liver scaffolds. Mitochondrial dysfunction in PNPLA3-I148M cells was linked to respiratory chain complex IV insufficiency. Antioxidant capacity was lower in PNPLA3-I148M HSCs, while reactive oxygen species secretion was increased in PNPLA3-I148M HSCs and higher in bioengineered cirrhotic vs. healthy scaffolds. TGFB1 signalling followed the same trend. In PNPLA3-I148M cells, expression and activation of the endogenous TGFB1 inhibitor NR4A1 were decreased: treatment with the Csn-B agonist increased total NR4A1 in HSCs cultured in healthy but not in cirrhotic 3D scaffolds. NR4A1 regulation by TGFB1/Csn-B was linked to Akt signalling in PNPLA3-WT HSCs and to Erk signalling in PNPLA3-I148M HSCs.

CONCLUSION

HSCs carrying the PNPLA3 I148M variant have impaired mitochondrial function, antioxidant responses, and increased TGFB1 signalling, which dampens antifibrotic NR4A1 activity. These features are exacerbated by cirrhotic ECM, highlighting the dual impact of the PNPLA3 I148M variant and the fibrotic microenvironment in progressive chronic liver diseases.

IMPACT AND IMPLICATIONS

Hepatic stellate cells (HSCs) play a key role in the fibrogenic process associated with chronic liver disease. The PNPLA3 genetic mutation has been linked with increased risk of fibrogenesis, but its role in HSCs requires further investigation. Here, by using comparative transcriptomics and a novel 3D in vitro model, we demonstrate the impact of the PNPLA3 genetic mutation on primary human HSCs' behaviour, and we show that it affects the cell's mitochondrial function and antioxidant response, as well as the antifibrotic gene NR4A1. Our publicly available transcriptomic data, 3D platform and our findings on NR4A1 could facilitate the discovery of targets to develop more effective treatments for chronic liver diseases.

Arsenic exposure induced renal fibrosis via regulation of mitochondrial dynamics and the NLRP3-TGF-β1/SMAD signaling pathway

Environmental arsenic exposure is one of the major global public health problems. Studies have shown that arsenic exposure can cause renal fibrosis, but the underlying mechanism is still unclear. Integrating the in vivo and in vitro models, this study investigated the potential molecular pathways for arsenic-induced renal fibrosis. In this study, SD rats were treated with 0, 5, 25, 50, and 100 mg/L NaAsO2 for 8 weeks via drinking water, and HK2 cells were treated with different doses of NaAsO2 for 48 h. The in vivo results showed that arsenic content in the rats' kidneys increased as the dose increased. Body weight decreased and kidney coefficient increased at 100 mg/L. As a response to the elevated NaAsO2 dose, inflammatory cell infiltration, renal tubular injury, glomerular atrophy, tubulointerstitial hemorrhage, and fibrosis became more obvious indicated by HE and Masson staining. The kidney transcriptome profiles further supported the protein-protein interactions involved in NaAsO2-induced renal fibrosis. The in vivo results, in together with the in vitro experiments, have revealed that exposure to NaAsO2 disturbed mitochondrial dynamics, promoted mitophagy, activated inflammation and the TGF-β1/SMAD signaling pathway, and finally resulted in fibrosis. In summary, arsenic exposure contributed to renal fibrosis via regulating the mitochondrial dynamics and the NLRP3-TGF-β1/SMAD signaling axis. This study presented an adverse outcome pathway for the development of renal fibrosis due to arsenic exposure through drinking water.

Specneuzhenide improves bleomycin-induced pulmonary fibrosis in mice via AMPK-dependent reduction of PD-L1

BACKGROUND

Pulmonary fibrosis (PF) is an escalating global health issue, characterized by rising rates of morbidity and mortality annually. Consequently, further investigation of potential damage mechanisms and potential preventive strategies for PF are warranted. Specnuezhenide (SPN), a prominent secoiridoid compound derived from Ligustrum lucidum Ait, exhibits anti-inflammatory and anti-oxidative capacities, indicating the potential therapeutic actions on PF. However, the underlying mechanisms of SPN on PF remain unclear.

PURPOSE

This work was aimed at investigating the protective actions of SPN on PF and the potential mechanism.

METHODS

In vivo, mice were administrated with bleomycin (BLM) to establish PF model. PF mice were treated with SPN (45/90 mg/kg) by gavage. In vitro, we employed TGF-β1 (10 ng/mL)-induced MLE-12 and PLFs cells, which then were treated with SPN (5, 10, 20 µM). DARTS assay, biofilm interference experiment and molecular docking were performed to investigate the molecular target of SPN.

RESULTS

In vivo, we found SPN treatment improved survival rate, alleviated pathological changes through reducing BLM-induced extracellular matrix (ECM) deposition, as well as BLM-induced epithelial-mesenchymal transition (EMT). In vitro, SPN inhibited EMT and lung fibroblast transdifferentiation. Mechanistically, SPN activated the AMPK protein to decrease the abnormally high level of PD-L1. Furthermore, the compound C, known as an AMPK inhibitor, exhibited a significant hindrance to the inhibition of SPN on TGF-β1-caused fibroblast transdifferentiation and proliferation. This outcome could be attributed to the fact that compound C could eliminate the inhibitory effects of SPN on PD-L1 expression. Interestingly, DARTS assay, biofilm interference experiment and molecular docking results all indicated that SPN could bind to AMPK, which suggested that SPN might be a potential agonist targeting AMPK protein.

CONCLUSION

Altogether, the results in our work illustrated that SPN promoted AMPK-dependent reduction of PD-L1 protein, contributing to the inhibition of fibrosis progression. Thus, SPN may represent a potential AMPK agonist for PF treatment.

Inhibition of TGF-β1/Smad3 signaling by compound 5aa: A potential treatment for idiopathic pulmonary fibrosis

The incidence of idiopathic pulmonary fibrosis (IPF) has been steadily increasing each year, posing significant challenges in its treatment. In this study, we conducted the design and synthesis of 23 new inhibitors that specifically target the TGF-β1/Smad3 pathway. Initially, we employed a cell model of TGF-β-induced pulmonary fibrosis, using cell survival rate and HYP expression as indicators to identify the potent ingredient 5aa, which demonstrated significant anti-pulmonary fibrosis activity. Subsequently, we induced mice with bleomycin (BLM) to establish an experimental animal model of pulmonary fibrosis, and evaluated the pharmacodynamics of 5aa in vivo against pulmonary fibrosis. The alterations in HYP and collagen levels in BLM-induced pulmonary fibrosis mice were analyzed using ELISA and immunohistochemistry techniques. The results indicated that compound 5aa effectively suppressed the fibrotic response induced by TGF-β1, inhibited the expression of the fibrotic marker α-SMA, and hindered the EMT process in NIH3T3 cells. Additionally, oral administration of 5aa demonstrated significant therapeutic effects in a mouse model of IPF, comparable to the established drug Nintedanib. Moreover, compound 5aa exhibited higher bioavailability in vivo compared to Nintedanib. These collective outcomes suggest that 5aa holds promise as a potential inhibitor of TGF-β1/Smad3 signaling for the treatment of IPF.

Esculin inhibits hepatic stellate cell activation and CCl4-induced liver fibrosis by activating the Nrf2/GPX4 signaling pathway

BACKGROUND

Liver fibrosis (LF) is a pathological process of the liver that threatens human health. Currently, effective treatments are still lacking. Esculin, a prominent constituent found in the Fraxinus rhynchophylla. (bark), Aesculus hippocastanum. (bark), and Cichorium intybus. (herb), has been shown to possess significant anti-inflammatory, antioxidant, and antibacterial properties. However, to date, there have been no studies investigating its potential efficacy in the treatment of LF.

OBJECTIVE

The study aims to investigate the therapeutic effect of esculin on LF and elucidate its potential molecular mechanism.

METHODS

Carbon tetrachloride (CCl4) was injected intraperitoneally to induce LF in mice, and transforming growth factor β1 (TGF-β1) was injected to induce LX-2 cells to investigate the improvement effect of esculin on LF. Kit, histopathological staining, immunohistochemistry (IHC), immunofluorescence (IF), polymerase chain reaction (PCR), and western blot (WB) were used to detect the expression of fiber markers and nuclear factor erythroid 2-related factor 2 (Nrf2)/glutathione peroxidase 4 (GPX4) signaling pathway in liver tissue and LX-2 cells. Finally, molecular docking, cellular thermal shift assay (CETSA), and drug affinity responsive target stability (DARTS) were used to verify the targeting between Nrf2 and esculin.

RESULTS

Esculin significantly inhibited CCl4-induced hepatic fibrosis and inflammation in mice. This was evidenced by the improvement of liver function indexes, fibrosis indicators, and histopathology. Additionally, esculin treatment prominently reduced the levels of pro-inflammatory factors, oxidative stress, and liver Fe2+ in CCl4-induced mice. In vitro studies also showed that esculin treatment significantly inhibited TGF-β1-induced LX-2 cell activation and decreased alpha-smooth muscle actin (α-SMA) and collagen I expression. Mechanism experiments proved that esculin can activate the Nrf2/GPX4 signaling pathway and inhibit liver ferroptosis. However, when LX-2 cells were treated with the Nrf2 inhibitor (ML385), the therapeutic effect of esculin significantly decreased.

CONCLUSION

This study is the first to demonstrate that esculin is a potential natural active ingredient in the treatment of LF, which can inhibit the activation of hepatic stellate cells (HSC) and improve LF. Its therapeutic effect is related to the activation of the Nrf2/GPX4 signaling pathway.

Calcitriol ameliorates the progression of hepatic fibrosis through autophagy-related gene 16-like 1-mediated autophagy

BACKGROUND

Calcitriol has the potential to counteract fibrotic diseases beyond its classical action of maintaining calcium and bone metabolism; however, its functional mechanism remains unknown. Autophagy-related gene 16-like 1 (Atg16l1) is one of the genes related to autophagy and is involved in protecting against fibrotic diseases. The present study aimed to explore the contribution of autophagy to the inhibition of calcitriol-induced hepatic fibrosis, as well as its potential molecular mechanism.

METHODS

Carbon tetrachloride (Ccl4)-treated mice were established as hepatic fibrosis models and received calcitriol treatment for 6 weeks. Quantification of Sirius red staining and measurement of key fibrotic markers (collagen-1 and α-SMA) was performed to detect hepatic fibrosis. Chloroquine (CQ) treatment was used to observe autophagic flux, and 3-methyladenine (3-MA) was used to inhibit autophagy. Furthermore, the effects of calcitriol on transforming growth factor β1 (TGFβ1)-stimulated primary hepatic stellate cells (HSCs) were detected. Downregulation of Atg16l1 or vitamin D receptor (VDR) in LX-2 cells was used to explore the mechanism of action of calcitriol in fibrosis and autophagy. Additionally, the electrophoretic mobility shift assay (EMSA) was used to investigate the interactions between VDR and ATG16L1.

RESULTS

Calcitriol increased the expression of VDR and ATG16L1, enhanced autophagy and attenuated hepatic fibrosis. 3-MA treatment and VDR silencing abolished the protective effects of calcitriol against fibrosis. Calcitriol-induced anti-fibrosis effects were blocked by ATG16L1 suppression. Furthermore, VDR bound to the ATG16L1 promoter and downregulation of VDR decreased the expression of ATG16L1 in LX-2 cells.

CONCLUSION

Calcitriol mitigates hepatic fibrosis partly through ATG16L1-mediated autophagy.

Recruitment or activation of mast cells in the liver aggravates the accumulation of fibrosis in carbon tetrachloride-induced liver injury

Liver diseases caused by viral infections, alcoholism, drugs, or chemical poisons are a significant health problem: Liver diseases are a leading contributor to mortality, with approximately 2 million deaths per year worldwide. Liver fibrosis, as a common liver disease characterized by excessive collagen deposition, is associated with high morbidity and mortality, and there is no effective treatment. Numerous studies have shown that the accumulation of mast cells (MCs) in the liver is closely associated with liver injury caused by a variety of factors. This study investigated the relationship between MCs and carbon tetrachloride (CCl4)-induced liver fibrosis in rats and the effects of the MC stabilizers sodium cromoglycate (SGC) and ketotifen (KET) on CCl4-induced liver fibrosis. The results showed that MCs were recruited or activated during CCl4-induced liver fibrosis. Coadministration of SCG or KET alleviated the liver fibrosis by decreasing SCF/c-kit expression, inhibiting the TGF-β1/Smad2/3 pathway, depressing the HIF-1a/VEGF pathway, activating Nrf2/HO-1 pathway, and increasing the hepatic levels of GSH, GSH-Px, and GR, thereby reducing hepatic oxidative stress. Collectively, recruitment or activation of MCs is linked to liver fibrosis and the stabilization of MCs may provide a new approach to the prevention of liver fibrosis.

NT-3 Combined with TGF-β Signaling Pathway Enhance the Repair of Spinal Cord Injury by Inhibiting Glial Scar Formation and Promoting Axonal Regeneration

This study investigated the mechanism of neurotrophin-3 (NT-3) in promoting spinal cord injury repair through the transforming growth factor-beta (TGF-β) signaling pathway. A mouse model of spinal cord injury was established. Forty C57BL/6J mice were randomized into model, NT-3, NT-3 + TGF-β1 and NT-3 + LY364947 groups. The Basso-Beattie-Bresnahan (BBB) scores of the NT-3 and NT-3 + LY364947 groups were significantly higher than the model group. The BBB score of the NT-3 + TGF-β1 group was significantly lower than NT-3 group. Hematoxylin-eosin staining and transmission electron microscopy showed reduction in myelin sheath injury, more myelinated nerve fibers in the middle section of the catheter, and relatively higher density and more neatly arranged regenerated axons in the NT-3 and NT-3 + LY364947 groups compared with the model and NT-3 + TGF-β1 groups. Immunofluorescence, TUNEL and Western blot analysis showed that compared with model group, the NEUN expression increased, and the apoptosis and Col IV, LN, CSPG, tenascin-C, Sema 3 A, EphB2 and Smad2/3 protein expression decreased significantly in the NT-3 and NT-3 + LY364947 groups; the condition was reversed in the NT-3 + TGF-β1 group compared with the NT-3 group. NT-3 combined with TGF-β signaling pathway promotes astrocyte differentiation, reduces axon regeneration inhibitory molecules, apoptosis and glial scar formation, promotes axon regeneration, and improves spinal cord injury.

Effect of simultaneous and sequential use of TGF-β1 and TGF-β3 with FGF-2 on teno/ligamentogenic differentiation of periodontal ligament stem cells

OBJECTIVE

The periodontal ligament is a crucial part of the periodontium, and its regeneration is challenging. This study compares the effect of simultaneous and sequential use of FGF-2 and TGF-β1 with FGF-2 and TGF-β3 on the periodontal ligament stem cells (PDLSCs) teno/ligamentogenic differentiation.

DESIGN

This study comprises ten different groups. A control group with only PDLSCs; FGF-2 group containing PDLSCs with a medium culture supplemented with FGF-2 (50 ng/mL). In other experimental groups, different concentrations (5 ng/mL or 10 ng/mL) of TGF-β1&-β3 simultaneously or sequentially were combined with FGF-2 on the cultured PDLSCs. TGF-β was added to the medium after day 3 in the sequential groups. Methyl Thiazolyl Tetrazolium (MTT) assay on days 3, 5, and 7 and Quantitative Real-time Polymerase Chain Reaction (RT-qPCR) analysis after day 7 were conducted to investigate PLAP1, SCX, and COL3A1, RUNX2 genes. All experiments were conducted in a triplicate. The One-way and Two-way ANOVA with Tukey post hoc were utilized to analyze the results of the MTT and RT-qPCR tests, respectively. A p-value less than 0.05 is considered significant.

RESULTS

The proliferation of cells on days 3, 5, and 7 was not significantly different among different experimental groups (P > 0.05). A higher expression of the PLAP1, SCX, and COL3A1 have been seen in groups with sequential use of growth factors; among these groups, the group using 5 ng/mL of TGF-β3 led other groups with the most amount of significant upregulation in PLAP1(17.69 ± 1.11 fold; P < 0.0001), SCX (5.71 ± 0.38 fold; P < 0.0001), and COL1A3 (6.35 ± 0.39 fold; P < 0.0001) expression, compared to the control group. The expression of the RUNX2 decreased in all groups compared to the control group; this reduction was more in groups with sequential use of growth factors.

CONCLUSION

The sequential use of growth factors can be more effective than simultaneous use in teno/ligamentogenic differentiation of PDLSCs. Moreover, treatment with 5 ng/mL TGF-β3 after FGF-2 was more effective than TGF-β1.

Nickel induces epithelial-mesenchymal transition in pulmonary fibrosis in mice via activation of the oxidative stress-mediated TGF-β1/Smad signaling pathway

Nickel (Ni) is recognized as a carcinogenic metal, and its widespread use has led to severe environmental and health problems. Although the lung is among the main organs affected by Ni, the precise mechanisms behind this effect remain poorly understood. This study aimed to elucidate the physiological mechanisms underlying Ni-induced pulmonary fibrosis (PF), using various techniques including histopathological detection, biochemical analysis, immunohistochemistry, western blotting, and quantitative real-time PCR. Mice were treated with nickel chloride (NiCl2), which induced PF (detected by Masson staining), up-regulation of α-smooth muscle actin (α-SMA), and collagen-1 mRNA and protein expression. NiCl2 was found to induce PF by: activation of the epithelial-mesenchymal transition (EMT) and the transforming growth factor-β1 (TGF-β1)/Smad signaling pathway; up-regulation of protein and mRNA expression of TGF-β1, p-Smad2, p-Smad3, vimentin, and N-cadherin; and down-regulation of protein and mRNA expression of E-cadherin. In addition, NiCl2 treatment increased malondialdehyde content while inhibiting antioxidant activity, as indicated by decreased catalase, total antioxidant capacity, and superoxide dismutase activities, and glutathione content. Co-treatment with the effective antioxidant and free radical scavenger N-acetyl cysteine (NAC) plus NiCl2 was used to study the effects of oxidative stress in NiCl2-induced PF. The addition of NAC significantly mitigated NiCl2-induced PF, and reversed activation of the TGF-β1/Smad signaling pathway and EMT. NiCl2-induced PF was therefore shown to be due to EMT activation via the TGF-β1/Smad signaling pathway, mediated by oxidative stress.

Paeoniflorin promotes PPARγ expression to suppress HSCs activation by inhibiting EZH2-mediated histone H3K27 trimethylation

BACKGROUND

The alleviating effect of paeoniflorin (Pae) on liver fibrosis has been established; however, the molecular mechanism and specific target(s) underlying this effect remain elusive.

PURPOSE

This study was to investigate the molecular mechanism underlying the regulatory effect of Pae on hepatic stellate cells (HSCs) activation in liver fibrosis, with a specific focus on the role of Pae in modulating histone methylation modifications.

METHODS

The therapeutic effect of Pae was evaluated by establishing in vivo and in vitro models of carbon tetrachloride (CCl4)-induced mice and transforming growth factor β1 (TGF-β1)-induced LX-2 cells, respectively. Molecular docking, surface plasmon resonance (SPR), chromatin immunoprecipitation-quantitative real time PCR (ChIP-qPCR) and other molecular biological methods were used to clarify the molecular mechanism of Pae regulating HSCs activation.

RESULTS

Our study found that Pae inhibited HSCs activation and histone trimethylation modification in liver of CCl4-induced mice and LX-2 cells. We demonstrated that the inhibitory effect of Pae on the activation of HSCs was dependent on peroxisome proliferator-activated receptor γ (PPARγ) expression and enhancer of zeste homolog 2 (EZH2). Mechanistically, Pae directly binded to EZH2 to effectively suppress its enzymatic activity. This attenuation leaded to the suppression of histone H3K27 trimethylation in the PPARγ promoter region, which induced upregulation of PPARγ expression.

CONCLUSION

This investigative not only sheds new light on the precise targets that underlie the remission of hepatic fibrogenesis induced by Pae but also emphasizes the critical significance of EZH2-mediated H3K27 trimethylation in driving the pathogenesis of liver fibrosis.

HIV coinfection exacerbates HBV-induced liver fibrogenesis through a HIF-1α- and TGF-β1-dependent pathway

BACKGROUND & AIMS

Persons with chronic HBV infection coinfected with HIV experience accelerated progression of liver fibrosis compared to those with HBV monoinfection. We aimed to determine whether HIV and its proteins promote HBV-induced liver fibrosis in HIV/HBV-coinfected cell culture models through HIF-1α and TGF-β1 signaling.

METHODS

The HBV-positive supernatant, purified HBV viral particles, HIV-positive supernatant, or HIV viral particles were directly incubated with cell lines or primary hepatocytes, hepatic stellate cells, and macrophages in mono or 3D spheroid coculture models. Cells were incubated with recombinant cytokines and HIV proteins including gp120. HBV sub-genomic constructs were transfected into NTCP-HepG2 cells. We also evaluated the effects of inhibitor of HIF-1α and HIV gp120 in a HBV carrier mouse model that was generated via hydrodynamic injection of the pAAV/HBV1.2 plasmid into the tail vein of wild-type C57BL/6 mice.

RESULTS

We found that HIV and HIV gp120, through engagement with CCR5 and CXCR4 coreceptors, activate AKT and ERK signaling and subsequently upregulate hypoxia-inducible factor-1α (HIF-1α) to increase HBV-induced transforming growth factor-β1 (TGF-β1) and profibrogenic gene expression in hepatocytes and hepatic stellate cells. HIV gp120 exacerbates HBV X protein-mediated HIF-1α expression and liver fibrogenesis, which can be alleviated by inhibiting HIF-1α. Conversely, TGF-β1 upregulates HIF-1α expression and HBV-induced liver fibrogenesis through the SMAD signaling pathway. HIF-1α small-interfering RNA transfection or the HIF-1α inhibitor (acriflavine) blocked HIV-, HBV-, and TGF-β1-induced fibrogenesis.

CONCLUSIONS

Our findings suggest that HIV coinfection exacerbates HBV-induced liver fibrogenesis through enhancement of the positive feedback between HIF-1α and TGF-β1 via CCR5/CXCR4. HIF-1α represents a novel target for antifibrotic therapeutic development in HBV/HIV coinfection.

IMPACT AND IMPLICATIONS

HIV coinfection accelerates the progression of liver fibrosis compared to HBV monoinfection, even among patients with successful suppression of viral load, and there is no sufficient treatment for this disease process. In this study, we found that HIV viral particles and specifically HIV gp120 promote HBV-induced hepatic fibrogenesis via enhancement of the positive feedback between HIF-1α and TGF-β1, which can be ameliorated by inhibition of HIF-1α. These findings suggest that targeting the HIF-1α pathway can reduce liver fibrogenesis in patients with HIV and HBV coinfection.

Eosinophil peroxidase promotes bronchial epithelial cells to secrete asthma-related factors and induces the early stage of airway remodeling

Asthma is a heterogeneous disease characterized by chronic airway inflammation, reversible airflow limitation, and airway remodeling. Eosinophil peroxidase (EPX) is the most abundant secondary granule protein unique to activated eosinophils. In this study, we aimed to illustrate the effect of EPX on the epithelial-mesenchymal transition (EMT) in BEAS-2B cells. Our research found that both EPX and ADAM33 were negatively correlated with FEV1/FVC and FEV1%pred, and positively correlated with IL-5 levels. Asthma patients had relatively higher levels of ADAM33 and EPX compared to the healthy control group. The expression of TSLP, TGF-β1 and ADAM33 in the EPX intervention group was significantly higher. Moreover, EPX could promote the proliferation, migration and EMT of BEAS-2B cells, and the effect of EPX on various factors was significantly improved by the PI3K inhibitor LY294002. The findings from this study could potentially offer a novel therapeutic target for addressing airway remodeling in bronchial asthma, particularly focusing on EMT.

Osthole ameliorates early diabetic kidney damage by suppressing oxidative stress, inflammation and inhibiting TGF-β1/Smads signaling pathway

BACKGROUND

Osthole is a natural active ingredient extracted from the traditional Chinese medicine Cnidium monnieri. It has been demonstrated to have anti-inflammatory, anti-fibrotic, and anti-hyperglycemic properties. However, its effect on diabetic kidney disease (DKD) remains uncertain. This study aims to assess the preventive and therapeutic effects of osthole on DKD and investigate its underlying mechanisms.

METHODS

A streptozotocin/high-fat and high-sucrose diet induced Type 2 diabetic rat model was established. Metformin served as the positive drug control. Diabetic rats were treated with metformin or three different doses of osthole for 8 weeks. Throughout the treatment period, the progression of DKD was assessed by monitoring increases in urinary protein, serum creatinine, urea nitrogen, and uric acid, along with scrutinizing kidney pathology. Enzyme-linked immunosorbent assay (ELISA) was employed to detect inflammatory factors and oxidative stress levels. At the same time, immunohistochemical staining was utilized to evaluate changes in alpha-smooth muscle actin, fibronectin, E-cadherin, and apoptosis. The alterations in TGF-β1/Smads signaling pathway were ascertained through western blot and immunofluorescence. Furthermore, we constructed a high glucose-stimulated HBZY-1 cells model to uncover its molecular protective mechanism.

RESULTS

Osthole significantly reduced fasting blood glucose, insulin resistance, serum creatinine, uric acid, blood urea nitrogen, urinary protein excretion, and glomerular mesangial matrix deposition in diabetic rats. Additionally, significant improvements were observed in inflammation, oxidative stress, apoptosis, and fibrosis levels. The increase of ROS, apoptosis and hypertrophy in HBZY-1 cells induced by high glucose was reduced by osthole. Immunofluorescence and western blot results demonstrated that osthole down-regulated the TGF-β1/Smads signaling pathway and related protein expression.

CONCLUSION

Our findings indicate that osthole exhibits potential preventive and therapeutic effects on DKD. It deserves further investigation as a promising drug for preventing and treating DKD.

RNA-seq combined network pharmacology reveals that Fu-Gan-Wan (FGW) inhibits liver fibrosis via NF-κB/CCL2/CCR2 and lipid peroxidation via Nrf2/HMOX1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Liver fibrosis is a serious complication of liver disease characterized by excessive collagen deposition, without effective therapeutic agents in the clinic. Fu-Gan-Wan (FGW) is an empirical formula used for the clinical treatment of hepatitis and cirrhosis. It has been shown to reverse experimental liver fibrosis. However, its corresponding mechanisms remain unclear.

AIM OF THE REVIEW

This study aimed to elucidate the key pathways and target genes of FGW in attenuating liver fibrosis.

MATERIALS AND METHODS

The therapeutic effects of different doses of FGW on liver fibrosis were investigated using a 2 mL/kg 15% CCl4-induced mouse model. Then, RNA-seq combined with network pharmacology was used to analyze the key biological processes and signaling pathways underlying the anti-liver fibrosis exertion of FGW. These findings were validated in a TGF-β1-induced model of activation and proliferation of mouse hepatic stellate cell line JS-1. Finally, the key signaling pathways and molecular targets were validated using animal tissues, and the effect of FGW on tissue lipid peroxidation was additionally observed.

RESULTS

We found that 19.5 g/kg FGW significantly down-regulated CCl4-induced elevation of hepatic ALT and AST, decreased collagen deposition, and inhibited the expression of pro-fibrotic factors α-SMA, COL1α1, CTGF, TIMP-1, as well as pro-inflammatory factor TGF-β1. Additionally, FGW at doses of 62.5, 125, and 250 μg/mL dose-dependently blocked JS-1 proliferation, migration, and activation. Furthermore, RNA-seq identified the NF-κB signaling pathway as a key target molecular pathway for FGW against liver fibrosis, and network pharmacology combined with RNA-seq focused on 11 key genes. Significant changes were identified in CCL2 and HMOX1 by tissue RT-PCR, Western blot, and immunohistochemistry. We further demonstrated that FGW significantly attenuated CCl4-induced increases in p-p65, CCL2, CCR2, and HMOX1, while significantly elevating Nrf2. Finally, FGW significantly suppressed the accumulation of lipid peroxidation products MDA and 4-HNE and reconfigured the oxidation-reduction balance, including promoting the increase of antioxidants GPx, GSH, and SOD, and the decrease of peroxidation products ROS and GSSG.

CONCLUSIONS

This study demonstrated that FGW exhibits potential in mitigating CCl4-induced hepatic fibrosis, lipid peroxidation, and iron metabolism disorders in mice. This effect may be mediated through the NF-κB/CCL2/CCR2 and Nrf2/HMOX1 pathways.

Modulating pancreatic cancer microenvironment: The efficacy of Huachansu in mouse models via TGF-β/Smad pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Huachansu (HCS) is a traditional Chinese medicine obtained from the dried skin glands of Bufo gargarizans and clinical uses of HCS have been approved in China to treat malignant tumors. The traditional Chinese medicine theory states that HCS relieves patients with cancer by promoting blood circulation to remove blood stasis. Clinical observation found that local injection of HCS given to pancreatic cancer patients can significantly inhibit tumor progression and assist in enhancing the efficacy of chemotherapy. However, the material basis and underlying mechanism have not yet been elucidated.

AIM OF THE STUDY

To investigate the therapeutic potential of HCS for the treatment of pancreatic cancer in in situ transplanted tumor nude mouse model. Furthermore, this study sought to elucidate the molecular mechanisms underlying its efficacy and assess the impact of HCS on the microenvironment of pancreatic cancer. To identify the antitumor effect of HCS in in situ transplanted tumor nude mouse model and determine the Chemopreventive mechanism of HCS on tumor microenvironment (TME).

METHODS

Using the orthotopic transplantation nude mouse model with fluorescently labeled pancreatic cancer cell lines SW1990 and pancreatic stellate cells (PSCs), we examined the effect of HCS on the pancreatic ductal adenocarcinoma (PDAC) microenvironment based on the transforming growth factor β (TGF-β)/Smad pathway. The expression of TGF-β, smad2, smad3, smad4, collagen type-1 genes and proteins in nude mouse model were detected by qRT-PCR and Western blot.

RESULTS

HCS significantly reduced tumor growth rate, increased the survival rate, and ameliorated the histopathological changes in the pancreas. It was found that HCS concentration-dependently reduced the expression of TGF-β1 and collagen type-1 genes and proteins, decreased the expression of Smad2 and Smad3 genes, and downregulated the phosphorylation level of Smad2/3. Additionally, the gene and protein expression of Smad4 were promoted by HCS. Further, the promoting effect gradually enhanced with the rise of HCS concentration.

CONCLUSIONS

The results demonstrated HCS could regulate the activity of the TGF-β/Smad pathway in PDAC, improved the microenvironment of PDAC and delayed tumor progression. This study not only indicated that the protective mechanism of HCS on PDAC might be attributed partly to the inhibition of cytokine production and the TGF-β/Smad pathway, but also provided evidence for HCS as a potential medicine for PDAC treatment.

[Study of metal organic framework with siRNA for overcoming matrix barrierin breast cancer]

Objective: This study aimed to develop a new delivery strategy that utilized metal organic framework (MOF) loaded with small-interfering RNA (siRNA) targeting ITGAV to overcome tumor matrix barrier, and thus enhance drug penetration and immune accessibility in breast cancer. Methods: MOF@siITGAV particles were constructed and characterized. The uptake of MOF@siITGAV in breast cancer cell line 4T1 was observed by the cellular uptake assay. The toxicity of MOF@siITGAV was detected by cell counting kit 8 (CCK-8). The blank control group, naked siITGAV group and MOF@siITGAV group were set. Real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) and Western blot were used to detect the expressions of ITGAV. The level of transforming growth factor β1 (TGF-β1) in the cell culture medium was detected by enzyme-linked immunosorbent assay (ELISA). The penetration of MOF@siITGAV in 4T1 cells was tested by constructing 3D spheroids. Mouse models of triple negative breast cancer were established. The effect of MOF@siITGAV on the growth of transplanted tumors and main organs was verified. Imminohistochemical (IHC) was used to test the expression of collagen and CD8. Results: MOF@siITGAV particles were constructed with sizes of (198.0±3.3) nm and zeta potential of -(20.2±0.4) mV. MOF@siITGAV could be engulfed by 4T1 cells and triggered to release siRNA. Compared to the blank control group, the expression of ITGAV in the MOF@siITGAV group [(46.5±11.3)%] and the naked siITGAV group [(109.9±19.0)%] was lower. TGF-β1 in the cell culture medium of the blank control group, naked siITGAV group, and MOF@siITGAV group was (474.5±34.4) pg/ml, (437.2±16.5) pg/ml, and (388.4±14.4) pg/ml, respectively. MOF@siITGAV could better penetrate into 4T1 spheroids and exhibit no obvious toxicity. The cell viability was (99.7±3.5)%, (98.2±5.2)%, (97.3±6.6)%, (92.1±8.1)%, and (92.4±4.1)%, respectively, after MOF@siITGAV treatment with the concentration of 0, 10, 20, 40, 80, and 160 μg/ml, respectively, for 24 h. The tumor growth in the MOF@siITGAV group was suppressed significantly. After 15-day treatment, the tumor volume of the MOF@siITGAV group was (135.3±41.9) mm3, smaller than that of the blank control group [(691.1±193.0) mm3] (P=0.025). The expression of collagen and the number of CD8 positive cells of the MOF@siITGAV group were lower than those of the other two groups. No significant abnormalities were observed in the main organs of mice. Conclusions: Targeting the integrinαv on the surface of cancer cells could destroy extracellular matrix, improve drug delivery, and increase immune infiltration.

Assessing the combined impact of fatty liver-induced TGF-β1 and LPS-activated macrophages in fibrosis through a novel 3D serial section methodology

Non-alcoholic steatohepatitis (NASH), caused by fat buildup, can lead to liver inflammation and damage. Elucidation of the spatial distribution of fibrotic tissue in the fatty liver in NASH can be immensely useful to understand its pathogenesis. Thus, we developed a novel serial section-3D (SS3D) technique that combines high-resolution image acquisition with 3D construction software, which enabled highly detailed analysis of the mouse liver and extraction and quantification of stained tissues. Moreover, we studied the underexplored mechanism of fibrosis progression in the fatty liver in NASH by subjecting the mice to a high-fat diet (HFD), followed by lipopolysaccharide (LPS) administration. The HFD/LPS (+) group showed extensive fibrosis compared with control; additionally, the area of these fibrotic regions in the HFD/LPS (+) group was almost double that of control using our SS3D technique. LPS administration led to an increase in Tnfα and Il1β mRNA expression and the number of macrophages in the liver. On the other hand, transforming growth factor-β1 (Tgfβ1) mRNA increased in HFD group compared to that of control group without LPS-administration. In addition, COL1A1 levels increased in hepatic stellate cell (HSC)-like XL-2 cells when treated with recombinant TGF-β1, which attenuated with recombinant latency-associated protein (rLAP). This attenuation was rescued with LPS-activated macrophages. Therefore, we demonstrated that fatty liver produced "latent-form" of TGF-β1, which activated by macrophages via inflammatory cytokines such as TNFα and IL1β, resulting in activation of HSCs leading to the production of COL1A1. Moreover, we established the effectiveness of our SS3D technique in creating 3D images of fibrotic tissue, which can be used to study other diseases as well.

Inhibitory effect of doxycycline conjugated with deoxycholic acid and polyethylenimine conjugate on nasal fibroblast differentiation and extracellular production

BACKGROUND

Chronic rhinosinusitis (CRS) is an inflammatory disease affecting the sinuses or nose. Persistent inflammatory responses can lead to tissue remodeling, which is a pathological characteristics of CRS. Activation of fibroblasts in the nasal mucosal stroma, differentiation and collagen deposition, and subepithelial fibrosis have been associated with CRS.

OBJECTIVES

We aimed to assess the inhibitory effects of doxycycline and deoxycholic acid-polyethyleneimine conjugate (DA3-Doxy) on myofibroblast differentiation and extracellular matrix (ECM) production in nasal fibroblasts stimulated with TGF-β1.

METHODS

To enhance efficacy, we prepared DA3-Doxy using a conjugate of low-molecular-weight polyethyleneimine (PEI) (MW 1800) and deoxycholic acid (DA) and Doxy. The synthesis of the DA3-Doxy polymer was confirmed using nuclear magnetic resonance, and the critical micelle concentration required for cationic micelle formation through self-assembly was determined. Subsequently, the Doxy loading efficiency of DA3 was assessed. The cytotoxicity of Doxy, DA3, PEI, and DA-Doxy in nasal fibroblasts was evaluated using the WST-1 assay. The anti-tissue remodeling and anti-inflammatory effects of DA3-Doxy and DA3 were examined using real-time polymerase chain reaction (Real-time PCR), immunocytochemistry, western blot, and Sircol assay.

RESULTS

Both DA3 and DA3-Doxy exhibited cytotoxicity at 10 μg/ml in nasal fibroblasts. Doxy partially inhibited α-smooth muscle actin, collagen types I and III, and fibronectin. However, DA3-Doxy significantly inhibited α-SMA, collagen types I and III, and fibronectin at 5 μg/ml. DA3-Doxy also modulated TGF-β1-induced changes in the expression of MMP 1, 2, and 9. Nonetheless, TGF-β1-induced expression of MMP3 was further increased by DA3-Doxy. The expression of TIMP 1 and 2 was partially reduced with 5 μg/ml DA3-Doxy.

CONCLUSIONS

Although initially developed for the delivery of genetic materials or drugs, DA3 exhibits inhibitory effects on myofibroblast differentiation and ECM production. Therefore, it holds therapeutic potential for CRS, and a synergistic effect can be expected when loaded with CRS treatment drugs.

Vinpocetine alleviated alveolar epithelial cells injury in experimental pulmonary fibrosis by targeting PPAR-γ/NLRP3/NF-κB and TGF-β1/Smad2/3 pathways

This study aimed to investigate the potential anti-fibrotic activity of vinpocetine in an experimental model of pulmonary fibrosis by bleomycin and in the MRC-5 cell line. Pulmonary fibrosis was induced in BALB/c mice by oropharyngeal aspiration of a single dose of bleomycin (5 mg/kg). The remaining induced animals received a daily dose of pirfenidone (as a standard anti-fibrotic drug) (300 mg/kg/PO) and vinpocetine (20 mg/kg/PO) on day 7 of the induction till the end of the experiment (day 21). The results of the experiment revealed that vinpocetine managed to alleviate the fibrotic endpoints by statistically improving (P ≤ 0.05) the weight index, histopathological score, reduced expression of fibrotic-related proteins in immune-stained lung sections, as well as fibrotic markers measured in serum samples. It also alleviated tissue levels of oxidative stress and inflammatory and pro-fibrotic mediators significantly elevated in bleomycin-only induced animals (P ≤ 0.05). Vinpocetine managed to express a remarkable attenuating effect in pulmonary fibrosis both in vivo and in vitro either directly by interfering with the classical TGF-β1/Smad2/3 signaling pathway or indirectly by upregulating the expression of Nrf2 enhancing the antioxidant system, activating PPAR-γ and downregulating the NLRP3/NF-κB pathway making it a candidate for further clinical investigation in cases of pulmonary fibrosis.

Loureirin B ameliorates cholestatic liver fibrosis via AKT/mTOR/ATG7-mediated autophagy of hepatic stellate cells

AIM OF THE STUDY

Chronic cholestasis leads to liver fibrosis, which lacks effective treatment. In this study, we investigated the role and mechanisms of action of loureirin B (LB) in cholestatic liver fibrosis.

MATERIALS AND METHODS

Bile duct ligation (BDL)-induced hepatic fibrosis mice were used as in vivo models. Transforming growth factor-β1 (TGF-β1)-pretreated HSC-T6 cells were used to explore the mechanism by which LB attenuates liver fibrosis in vitro. RNA sequencing, quantitative PCR (qPCR), western blotting, immunohistochemistry and immunofluorescence were performed to detect the fibrosis markers and measure autophagy levels. Flow cytometry, cell counting kit-8 (CCK-8) assay, and 5'-ethynyl-2'-deoxyuridine (EdU) assay were conducted to detect cell proliferation and viability. GFP-RFP-LC3 adenovirus, autophagy-related protein 7 (ATG7) siRNA, and bafilomycin A1 (BafA1) were used to verify autophagic flux.

RESULTS

Our results showed that LB ameliorates liver injury, inhibits collagen deposition, and decreases the expressions of fibrosis-related markers in BDL-induced mouse livers. In vitro, we found that LB inhibited proliferation and migration, promoted apoptosis, and inhibited the activation of HSC-T6 cells pretreated with TGF-β1. RNA sequencing analysis of HSC-T6 cells showed that LB treatment predominantly targeted autophagy-related pathways. Further protein analysis indicated that LB downregulated the expression of phosphorylated AKT (p-AKT) and phosphorylated mTOR (p-mTOR), and upregulated LC3-II, p62, and ATG7 both in vivo and in vitro. Intriguingly, ATG7 inactivation reversed the antifibrotic effects of LB on HSC-T6 cells.

CONCLUSIONS

LB can improve BDL-induced liver fibrosis by inhibiting the activation and proliferation of HSCs and is expected to be a promising antifibrotic drug.

DNA of Neutrophil Extracellular Traps Binds TMCO6 to Impair CD8+ T-cell Immunity in Hepatocellular Carcinoma

Neutrophil extracellular traps (NET), formed by the extracellular release of decondensed chromatin and granules, have been shown to promote tumor progression and metastasis. Tumor-associated neutrophils in hepatocellular carcinoma (HCC) are prone to NET formation, highlighting the need for a more comprehensive understanding of the mechanisms of action of NETs in liver cancer. Here, we showed that DNA of NETs (NET-DNA) binds transmembrane and coiled-coil domains 6 (TMCO6) on CD8+ T cells to impair antitumor immunity and thereby promote HCC progression. TGFβ1 induced NET formation, which recruited CD8+ T cells. Binding to NET-DNA inhibited CD8+ T cells function while increasing apoptosis and TGFβ1 secretion, forming a positive feedback loop to further stimulate NET formation and immunosuppression. Mechanistically, the N-terminus of TMCO6 interacted with NET-DNA and suppressed T-cell receptor signaling and NFκB p65 nuclear translocation. Blocking NET formation by inhibiting PAD4 induced potent antitumor effects in wild-type mice but not TMCO6-/- mice. In clinical samples, CD8+ T cells expressing TMCO6 had an exhausted phenotype. TGFβ1 signaling inhibition or TMCO6 deficiency combined with anti-PD-1 abolished NET-driven HCC progression in vivo. Collectively, this study unveils the role of NET-DNA in impairing CD8+ T-cell immunity by binding TMCO6 and identifies targeting this axis as an immunotherapeutic strategy for blocking HCC progression.

SIGNIFICANCE

TMCO6 is a receptor for DNA of NETs that mediates CD8+ T-cell dysfunction in HCC, indicating that the NET-TMCO6 axis is a promising target for overcoming immunosuppression in liver cancer.

Resveratrol attenuates inflammation and fibrosis in rheumatoid arthritis-associated interstitial lung disease via the AKT/TMEM175 pathway

BACKGROUND AND PURPOSE

Interstitial lung disease (ILD) represents a significant complication of rheumatoid arthritis (RA) that lacks effective treatment options. This study aimed to investigate the intrinsic mechanism by which resveratrol attenuates rheumatoid arthritis complicated with interstitial lung disease through the AKT/TMEM175 pathway.

METHODS

We established an arthritis model by combining chicken type II collagen and complete Freund's adjuvant. Resveratrol treatment was administered via tube feeding for 10 days. Pathological changes in both the joints and lungs were evaluated using HE and Masson staining techniques. Protein expression of TGF-β1, AKT, and TMEM175 was examined in lung tissue. MRC-5 cells were stimulated using IL-1β in combination with TGF-β1 as an in vitro model of RA-ILD, and agonists of AKT, metabolic inhibitors, and SiRNA of TMEM175 were used to explore the regulation and mechanism of action of resveratrol RA-ILD.

RESULTS

Resveratrol mitigates fibrosis in rheumatoid arthritis-associated interstitial lung disease and reduces oxidative stress and inflammation in RA-ILD. Furthermore, resveratrol restored cellular autophagy. When combined with the in vitro model, it was further demonstrated that resveratrol could suppress TGF-β1 expression, and reduce AKT metamorphic activation, consequently inhibiting the opening of AKT/MEM175 ion channels. This, in turn, lowers lysosomal pH and enhances the fusion of autophagosomes with lysosomes, ultimately ameliorating the progression of RA-ILD.

CONCLUSION

In this study, we demonstrated that resveratrol restores autophagic flux through the AKT/MEM175 pathway to attenuate inflammation as well as fibrosis in RA-ILD by combining in vivo and in vitro experiments. It further provides a theoretical basis for the selection of therapeutic targets for RA-ILD.

Emodin improves renal fibrosis in chronic kidney disease by regulating mitochondrial homeostasis through the mediation of peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α)

Chronic kidney disease (CKD) is a leading public health issue associated with high morbidity worldwide. However, there are only a few effective therapeutic strategies for CKD. Emodin, an anthraquinone compound from rhubarb, can inhibit fibrosis in tissues and cells. Our study aims to investigate the antifibrotic effect of emodin and the underlying molecular mechanism. A unilateral ureteral obstruction (UUO)-induced rat model was established to evaluate the effect of emodin on renal fibrosis development. Hematoxylin and eosin staining, Masson's trichrome staining, and immunohistochemistry staining were performed to analyze histopathological changes and fibrotic features after emodin treatment. Subsequently, a transforming growth factor-beta 1 (TGF-β1)-induced cell model was used to assess the inhibition of emodin on cell fibrosis in vitro. Furthermore, Western blot analysis and real-time quantitative reverse transcription-polymerase chain reaction were performed to validate the regulatory mechanism of emodin on renal fibrosis progression. As a result, emodin significantly improved histopathological abnormalities in rats with UUO. The expression of fibrosis biomarkers and mitochondrial biogenesis-related proteins also decreased after emodin treatment. Moreover, emodin blocked TGF-β1-induced fibrotic phenotype, lipid accumulation, and mitochondrial homeostasis in NRK-52E cells. Conversely, peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α) silencing significantly reversed these features in emodin-treated cells. Collectively, emodin plays an important role in regulating PGC-1α-mediated mitochondria function and energy homeostasis. This indicates that emodin exhibits great inhibition against renal fibrosis and acts as a promising inhibitor of CKD.

Modulatory effect of interleukin-2 loaded chitosan nano sphere on regulatory T cell activity in streptozotocin-induced diabetic mice

OBJECTIVE

The current study aimed to assess the modulating effect of IL-2 encapsulated chitosan-nanoparticles (CSNPs) on the function of Treg cells through induction of type 1 diabetes (T1D). Treg cell function was monitored by the forkhead box P3 (FoxP3) and transforming growth factor beta (TGFβ) levels, correlating them with blood glucose and serum insulin levels.

MATERIALS AND METHODS

In this case-control study, a low dose of IL-2 (free and chitosan-loaded) was injected into a diabetic mice group. The levels of FoxP3 and TGF-β 1 were assessed using Enzyme-Linked Immunosorbent Assay. In addition, blood glucose and serum insulin levels were determined.

RESULTS

The mean glucose level decreased significantly after free rIL-2 or rIL-2 / CSNPs treatment. Meanwhile, the mean serum insulin level was significantly increased after treatment with free rIL-2 or rIL-2/CSNPs. The mean levels of FoxP3 and TGFβ 1 were significantly increased with either free rIL-2 or rIL-2/CSNPs compared to the T1D untreated group (P < 0.001). In the treated mice group receiving free CSNPs, there was a significant negative correlation between glucose and insulin levels. Moreover, FoxP3 & TGFβ 1 levels had a significant positive correlation. In treated mice groups with free rIL-2 and IL-2 CSNPs, there was a significant positive correlation between FoxP3 and glucose levels. A significant negative correlation was found after conducting a correlation between insulin level and FoxP3 in the T1D/ rIL-2 / CSNPs group.

CONCLUSIONS

Low-dose IL-2 selectively modulates FoxP3 + Tregs, and TGFβ 1 increases their levels. These results demonstrated that IL-2-free and chitosan-loaded nanoparticles can be therapeutic agents in T1D.

Interval training suppresses nod-like receptor protein 3 inflammasome activation to improve cardiac function in myocardial infarction rats by hindering the activation of the transforming growth factor-β1 pathway

OBJECTIVE

Myocardial infarction (MI) -induced cardiac dysfunction can be attenuated by aerobic exercises. This study explored the mechanism of interval training (IT) regulating cardiac function in MI rats, providing some theoretical basis for clarifying MI pathogenesis and new ideas for clinically treating MI.

METHODS

Rats were subjected to MI modeling, IT intervention, and treatments of the Transforming growth factor-β1 (TGF-β1) pathway or the nod-like receptor protein 3 (NLRP3) activators. Cardiac function and hemodynamic indicator alterations were observed. Myocardial pathological damage and fibrosis, reactive oxygen species (ROS) level, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities, MDA content, inflammasome-associated protein levels, and inflammatory factor levels were assessed. The binding between TGF-β1 and receptor was detected.

RESULTS

MI rats exhibited decreased left ventricle ejection fraction (LVEF), left ventricle fractional shortening  (LVFS), left ventricular systolic pressure  (LVSP), positive and negative derivates max/min (dP/dt max/min) and increased left ventricular end-systolic pressure (LVEDP), a large number of scar areas in myocardium, disordered cell arrangement and extensive fibrotic lesions, increased TGF-β1 and receptor binding, elevated ROS level and MDA content and weakened SOD, CAT and GSH-Px activities, and up-regulated NLRP3, apoptosis-associated speck-like protein containing a CARD  (ASC) and cleaved-caspase-1 levels, while IT intervention caused ameliorated cardiac function. IT inactivated the TGF-β1 pathway to decrease oxidative stress in myocardial tissues of MI rats and inhibit NLRP3 inflammasome activation. Activating NLRP3 partially reversed IT-mediated improvement on cardiac function in MI rats.

CONCLUSION

IT diminished oxidative stress in myocardial tissues and suppressed NLRP3 inflammasome activation via inactivating the TGF-β1 pathway, thus improving the cardiac function of MI rats.

Qingfei xieding prescription ameliorates mitochondrial DNA-initiated inflammation in bleomycin-induced pulmonary fibrosis through activating autophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Qingfei Xieding prescription was gradually refined and produced by Hangzhou Red Cross Hospital. The raw material includes Ephedra sinica Stapf, Morus alba L., Bombyx Batryticatus, Gypsum Fibrosum, Prunus armeniaca L. var. ansu Maxim., Houttuynia cordata Thunb. , Pueraria edulis Pamp. Paeonia L., Scutellaria baicalensis Georgi and Anemarrhena asphodeloides Bge. It is effective in clinical adjuvant treatment of patients with pulmonary diseases.

AIM OF THE STUDY

To explore the efficacy and underlying mechanism of Qingfei Xieding (QF) in the treatment of bleomycin-induced mouse model.

MATERIALS AND METHODS

TGF-β induced fibrotic phenotype in vitro. Bleomycin injection induced lung tissue fibrosis mouse model in vivo. Flow cytometry was used to detect apoptosis, cellular ROS and lipid oxidation. Mitochondria substructure was observed by transmission electron microscopy. Autophagolysosome and nuclear entry of P65 were monitored by immunofluorescence. Quantitative real-time PCR was performed to detect the transcription of genes associated with mtDNA-cGAS-STING pathway and subsequent inflammatory signaling activation.

RESULTS

TGF-β induced the expression of α-SMA and Collagen I, inhibited cell viability in lung epithelial MLE-12 cells that was reversed by QF-containing serum. TGF-β-mediated downregulation in autophagy, upregulation in lipid oxidation and ROS contents, and mitochondrial damage were rescued by QF-containing serum treatment, but CQ exposure, an autophagy inhibitor, prevented the protective role of QF. In addition to that, the decreased autophagolysosome in TGF-β-exposed MLE-12 cells was reversed by QF and restored to low level in the combination treatment of QF and CQ. Mechanistically, QF-containing serum treatment significantly inhibited mtDNA-cGAS-STING pathway and subsequent inflammatory signaling in TGF-β-challenged cells, which were abolished by CQ-mediated autophagy inhibition. In bleomycin-induced mouse model, QF ameliorated pulmonary fibrosis, reduced mortality, re-activated autophagy in lung tissues and restrained mtDNA-cGAS-STING inflammation pathway. However, the protective effects of QF in bleomycin-induced model mice were also abrogated by CQ.

CONCLUSION

QF alleviated bleomycin-induced pulmonary fibrosis by activating autophagy, inhibiting mtDNA-cGAS-STING pathway-mediated inflammation. This research recognizes the protection role of QF on bleomycin-induced mouse model, and offers evidence for the potentiality of QF in clinical application for pulmonary fibrosis treatment.

Sinomenine attenuates pulmonary fibrosis by downregulating TGF-β1/Smad3, PI3K/Akt and NF-κB signaling pathways

BACKGROUND

Since COVID-19 became a global epidemic disease in 2019, pulmonary fibrosis (PF) has become more prevalent among persons with severe infections, with IPF being the most prevalent form. In traditional Chinese medicine, various disorders are treated using Sinomenine (SIN). The SIN's strategy for PF defense is unclear.

METHODS

Bleomycin (BLM) was used to induce PF, after which inflammatory factors, lung histological alterations, and the TGF-/Smad signaling pathway were assessed. By administering various dosages of SIN and the TGF- receptor inhibitor SB-431,542 to human embryonic lung fibroblasts (HFL-1) and A549 cells, we were able to examine proliferation and migration as well as the signaling molecules implicated in Epithelial-Mesenchymal Transition (EMT) and Extra-Cellular Matrix (ECM).

RESULTS

In vivo, SIN reduced the pathological changes in the lung tissue induced by BLM, reduced the abnormal expression of inflammatory cytokines, and improved the weight and survival rate of mice. In vitro, SIN inhibited the migration and proliferation by inhibiting TGF-β1/Smad3, PI3K/Akt, and NF-κB pathways, prevented the myofibroblasts (FMT) of HFL-1, reversed the EMT of A549 cells, restored the balance of matrix metalloenzymes, and reduced the expression of ECM proteins.

CONCLUSION

SIN attenuated PF by down-regulating TGF-β/Smad3, PI3K/Akt, and NF-κB signaling pathways, being a potential effective drug in the treatment of PF.

Cordycepin alleviates hepatic fibrosis in association with the inhibition of glutaminolysis to promote hepatic stellate cell senescence

Cordycepin (CRD) is an active component derived from Cordyceps militaris, which possesses multiple biological activities and uses in liver disease. However, whether CRD improves liver fibrosis by regulating hepatic stellate cell (HSC) activation has remained unknown. The study aims further to clarify the activities of CRD on liver fibrosis and elucidate the possible mechanism. Our results demonstrated that CRD significantly relieved hepatocyte injury and inhibited HSC activation, alleviating hepatic fibrogenesis in the Diethyl 1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylate (DDC)-induced mice model. In vitro, CRD exhibited dose-dependent repress effects on HSC proliferation, migration, and pro-fibrotic function in TGF-β1-activated LX-2 and JS-1 cells. The functional enrichment analysis of RNA-seq data indicated that the pathway through which CRD alleviates HSC activation involves cellular senescence and cell cycle-related pathways. Furthermore, it was observed that CRD accumulated the number of senescence-associated a-galactosidase positive cells and the levels of senescencemarker p21, and provoked S phasearrestof activated HSC. Remarkably, CRD treatment abolished TGF-β-induced yes-associated protein (YAP) nuclear translocation that acts upstream of glutaminolysis in activated HSC. On the whole, CRD significantly inhibited glutaminolysis of activated-HSC and induced cell senescence through the YAP signaling pathway, consequently alleviating liver fibrosis, which may be a valuable supplement for treating liver fibrosis.

Simvastatin attenuates silica-induced pulmonary inflammation and fibrosis in rats via the AMPK-NOX pathway

BACKGROUND

Simvastatin (Sim), a hydroxy-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, has been widely used in prevention and treatment of cardiovascular diseases. Studies have suggested that Sim exerts anti-fibrotic effects by interfering fibroblast proliferation and collagen synthesis. This study was to determine whether Sim could alleviate silica-induced pulmonary fibrosis and explore the underlying mechanisms.

METHODS

The rat model of silicosis was established by the tracheal perfusion method and treated with Sim (5 or 10 mg/kg), AICAR (an AMPK agonist), and apocynin (a NOX inhibitor) for 28 days. Lung tissues were collected for further analyses including pathological histology, inflammatory response, oxidative stress, epithelial mesenchymal transformation (EMT), and the AMPK-NOX pathway.

RESULTS

Sim significantly reduced silica-induced pulmonary inflammation and fibrosis at 28 days after administration. Sim could reduce the levels of interleukin (IL)-1β, IL-6, tumor necrosis factor-α and transforming growth factor-β1 in lung tissues. The expressions of hydroxyproline, α-SMA and vimentin were down-regulated, while E-cad was increased in Sim-treated rats. In addition, NOX4, p22pox, p40phox, p-p47phox/p47phox expressions and ROS levels were all increased, whereas p-AMPK/AMPK was decreased in silica-induced rats. Sim or AICAR treatment could notably reverse the decrease of AMPK activity and increase of NOX activity induced by silica. Apocynin treatment exhibited similar protective effects to Sim, including down-regulating of oxidative stress and inhibition of the EMT process and inflammatory reactions.

CONCLUSIONS

Sim attenuates silica-induced pulmonary inflammation and fibrosis by downregulating EMT and oxidative stress through the AMPK-NOX pathway.

Spon1+ inflammatory monocytes promote collagen remodeling and lung cancer metastasis through lipoprotein receptor 8 signaling

Lung cancer is the leading cause of cancer-related deaths in the world, and non-small cell lung cancer (NSCLC) is the most common subset. We previously found that infiltration of tumor inflammatory monocytes (TIMs) into lung squamous carcinoma (LUSC) tumors is associated with increased metastases and poor survival. To further understand how TIMs promote metastases, we compared RNA-Seq profiles of TIMs from several LUSC metastatic models with inflammatory monocytes (IMs) of non-tumor-bearing controls. We identified Spon1 as upregulated in TIMs and found that Spon1 expression in LUSC tumors corresponded with poor survival and enrichment of collagen extracellular matrix signatures. We observed SPON1+ TIMs mediate their effects directly through LRP8 on NSCLC cells, which resulted in TGF-β1 activation and robust production of fibrillar collagens. Using several orthogonal approaches, we demonstrated that SPON1+ TIMs were sufficient to promote NSCLC metastases. Additionally, we found that Spon1 loss in the host, or Lrp8 loss in cancer cells, resulted in a significant decrease of both high-density collagen matrices and metastases. Finally, we confirmed the relevance of the SPON1/LRP8/TGF-β1 axis with collagen production and survival in patients with NSCLC. Taken together, our study describes how SPON1+ TIMs promote collagen remodeling and NSCLC metastases through an LRP8/TGF-β1 signaling axis.

MiR-146a reduces fibrosis after glaucoma filtration surgery in rats

PURPOSE

To explore the impact of microRNA 146a (miR-146a) and the underlying mechanisms in profibrotic changes following glaucoma filtering surgery (GFS) in rats and stimulation by transforming growth factor (TGF)-β1 in rat Tenon's capsule fibroblasts.

METHODS

Cultured rat Tenon's capsule fibroblasts were treated with TGF-β1 and analyzed with microarrays for mRNA profiling to validate miR-146a as the target. The Tenon's capsule fibroblasts were then respectively treated with lentivirus-mediated transfection of miR-146a mimic or inhibitor following TGF-β1 stimulation in vitro, while GFS was performed in rat eyes with respective intraoperative administration of miR-146a, mitomycin C (MMC), or 5-fluorouracil (5-FU) in vivo. Profibrotic genes expression levels (fibronectin, collagen Iα, NF-KB, IL-1β, TNF-α, SMAD4, and α-smooth muscle actin) were determined through qPCR, Western blotting, immunofluorescence staining and/or histochemical analysis in vitro and in vivo. SMAD4 targeting siRNA was further used to treat the fibroblasts in combination with miR-146a intervention to confirm its role in underlying mechanisms.

RESULTS

Upregulation of miR-146a reduced the proliferation rate and profibrotic changes of rat Tenon's capsule fibroblasts induced by TGF-β1 in vitro, and mitigated subconjunctival fibrosis to extend filtering blebs survival after GFS in vivo, where miR-146a decreased expression levels of NF-KB-SMAD4-related genes, such as fibronectin, collagen Iα, NF-KB, IL-1β, TNF-α, SMAD4, and α-smooth muscle actin(α-SMA). Additionally, SMAD4 is a key target gene in the process of miR-146a inhibiting fibrosis.

CONCLUSIONS

MiR-146a effectively reduced TGF-β1-induced fibrosis in rat Tenon's capsule fibroblasts in vitro and in vivo, potentially through the NF-KB-SMAD4 signaling pathway. MiR-146a shows promise as a novel therapeutic target for preventing fibrosis and improving the success rate of GFS.

Design, synthesis and evaluation of a pyrazolo[3,4-d]pyrimidine derivative as a novel and potent TGFβ1R1 inhibitor

The transforming growth factor β1 (TGFβ1)/SMAD signaling pathway regulates many vital physiological processes. The development of potent inhibitors targeting activin receptor-like kinase 5 (ALK5) would provide potential treatment reagents for various diseases. A significant number of ALK5 inhibitors have been discovered, and they are currently undergoing clinical evaluation at various stages. However, the clinical demands were far from being met. In this study, we utilized an alternative conformation-similarity-based virtual screening (CSVS) combined with a fragment-based drug designing (FBDD) strategy to efficiently discover a potent and active hit with a novel chemical scaffold. After structural optimization in the principle of group replacement, compound 57 was identified as the most promising ALK5 inhibitor. Compound 57 demonstrated significant inhibitory effects against the TGF-β1/SMAD signaling pathway. It could markedly attenuate the production of extracellular matrix (ECM) and deposition of collagen. Also, the lead compound showed adequate pharmacokinetic (PK) properties and good in vivo tolerance. Moreover, treatment with compound 57 in two different xerograph models showed significant inhibitory effects on the growth of pancreatic cancer cells. These results suggested that lead compound 57 refers as a promising ALK5 inhibitor both in vitro and in vivo, which merits further validation.

Potential inhibitory effect of geraniol isolated from lemongrass (Cymbopogon commutatus Stapf) on tilmicosin-induced oxidative stress in cardiac tissue

An experimental study has been conducted to investigate the efficacy of geraniol (GNL) isolated from lemomgrass in protecting against cardiac toxicity induced by tilmicosin (TIL) in albino mice. Compared to TIL-treated mice, those supplemented with GNL had a thicker left ventricular wall and a smaller ventricular cavity. Studies of TIL animals treated with GNL showed that their cardiomyocytes had markedly changed in diameter and volume, along with a reduction in numerical density. After TIL induction, animals showed a significant increase in the protein expression of TGF-β1, TNF-α, nuclear factor kappa B (NF-kB), by 81.81, 73.75 and 66.67%, respectively, and hypertrophy marker proteins ANP, BNP, and calcineurin with respective percentages of 40, 33.34 and 42.34%. Interestingly, GNL significantly decreased the TGF-β1, TNF-α, NF-kB, ANP, BNP, and calcineurin levels by 60.94, 65.13, 52.37, 49.73, 44.18 and 36.84%, respectively. As observed from histopathology and Masson's trichrome staining, supplementation with GNL could rescue TIL-induced cardiac hypertrophy. According to these results, GNL may protect the heart by reducing hypertrophy in mice and modulating biomarkers of fibrosis and apoptosis.

Dysregulation of TNF-induced protein 3 and CCAAT/enhancer-binding protein β in alveolar macrophages: Implications for systemic sclerosis-associated interstitial lung disease

OBJECTIVES

This study investigates the role of TNF-induced protein 3 (TNFAIP3) and CCAAT/enhancer-binding protein β (C/EBPβ) in alveolar macrophages (AMs) of patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD) and their influence on pulmonary fibrosis.

METHODS

Transfection of HEK293T cells and AMs with plasmids carrying TNFAIP3 and C/EBPβ was performed, followed by co-culturing AMs with pulmonary fibroblasts. Immunoblotting analysis was then utilized to assess the expression of TNFAIP3, C/EBPβ, and collagen type 1 (Col1). Quantitative PCR analysis was conducted to quantify the mRNA levels of C/EBPβ, IL-10, and TGF-β1. STRING database analysis, and immunoprecipitation assays were employed to investigate the interactions between TNFAIP3 and C/EBPβ.

RESULTS

TNFAIP3 expression was significantly reduced in SSc-ILD AMs, correlating with increased Col1 production in fibroblasts. Overexpression of TNFAIP3 inhibited this pro-fibrotic activity. Conversely, C/EBPβ expression was elevated in SSc-ILD AMs, and its reduction through TNFAIP3 restoration decreased pro-fibrotic cytokines IL-10 and TGFβ1 levels. Protein-protein interaction studies confirmed the regulatory relationship between TNFAIP3 and C/EBPβ.

CONCLUSIONS

This study highlights the important role of TNFAIP3 in regulating pulmonary fibrosis in SSc-ILD by modulating C/EBPβ expression in AMs. These findings suggest that targeting TNFAIP3 could be a potential therapeutic strategy for managing SSc-ILD patients.

Lactoferrin as a therapeutic agent for attenuating hepatic stellate cell activation in thioacetamide-induced liver fibrosis

Liver fibrosis is a chronic liver disease caused by prolonged liver injuries. Excessive accumulation of extracellular matrix replaces the damaged hepatocytes, leading to fibrous scar formation and fibrosis induction. Lactoferrin (LF) is a glycoprotein with a conserved, monomeric signal polypeptide chain, exhibiting diverse physiological functions, including antioxidant, anti-inflammatory, antibacterial, antifungal, antiviral, and antitumoral activities. Previous study has shown LF's protective role against chemically-induced liver fibrosis in rats. However, the mechanisms of LF in liver fibrosis are still unclear. In this study, we investigated LF's mechanisms in thioacetamide (TAA)-induced liver fibrosis in rats and TGF-β1-treated HSC-T6 cells. Using ultrasonic imaging, H&E, Masson's, and Sirius Red staining, we demonstrated LF's ability to improve liver tissue damage and fibrosis induced by TAA. LF reduced the levels of ALT, AST, and hydroxyproline in TAA-treated liver tissues, while increasing catalase levels. Additionally, LF treatment decreased mRNA expression of inflammatory factors such as Il-1β and Icam-1, as well as fibrogenic factors including α-Sma, Collagen I, and Ctgf in TAA-treated liver tissues. Furthermore, LF reduced TAA-induced ROS production and cell death in FL83B cells, and decreased α-SMA, Collagen I, and p-Smad2/3 productions in TGF-β1-treated HSC-T6 cells. Our study highlights LF's ability to ameliorate TAA-induced hepatocyte damage, oxidative stress, and liver fibrosis in rats, potentially through its inhibitory effect on HSC activation. These findings suggest LF's potential as a therapeutic agent for protecting against liver injuries and fibrosis.

Nr4a1 enhances Wnt4 transcription to promote mesenchymal stem cell osteogenesis and alleviates inflammation-inhibited bone regeneration

Intense inflammatory response impairs bone marrow mesenchymal stem cell (BMSC)-mediated bone regeneration, with transforming growth factor (TGF)-β1 being the most highly expressed cytokine. However, how to find effective and safe means to improve bone formation impaired by excessive TGF-β1 remains unclear. In this study, we found that the expression of orphan nuclear receptor Nr4a1, an endogenous repressor of TGF-β1, was suppressed directly by TGF-β1-induced Smad3 and indirectly by Hdac4, respectively. Importantly, Nr4a1 overexpression promoted BMSC osteogenesis and reversed TGF-β1-mediated osteogenic inhibition and pro-fibrotic effects. Transcriptomic and histologic analyses confirmed that upregulation of Nr4a1 increased the transcription of Wnt family member 4 (Wnt4) and activated Wnt pathway. Mechanistically, Nr4a1 bound to the promoter of Wnt4 and regulated its expression, thereby enhancing the osteogenic capacity of BMSCs. Moreover, treatment with Nr4a1 gene therapy or Nr4a1 agonist Csn-B could promote ectopic bone formation, defect repair, and fracture healing. Finally, we demonstrated the correlation of NR4A1 with osteogenesis and the activation of the WNT4/β-catenin pathway in human BMSCs and fracture samples. Taken together, these findings uncover the critical role of Nr4a1 in bone formation and alleviation of inflammation-induced bone regeneration disorders, and suggest that Nr4a1 has the potential to be a therapeutic target for accelerating bone healing.

High expression of SLC7A1 in high-grade serous ovarian cancer promotes tumor progression and is involved in MAPK/ERK pathway and EMT

Our previous studies have shown that upregulation of SLC7A1 in epithelial ovarian cancer (EOC) tumor cells significantly increases cancer cell proliferation, migration, and cisplatin resistance; however, the molecular mechanism by which SLC7A1 functions in EOC remains unknown. In later studies, we found that SLC7A1 is also highly expressed in the interstitial portion of high-grade serous ovarian cancer (HGSOC), but the significance of this high expression in the interstitial remains unclear. Here, we showed the Interstitial high expression of SLC7A1 in HGSOC by immunohistochemistry. SLC7A1 enriched in cancer-associated fibroblasts (CAFs) was upregulated by TGF-β1. Transwell assay, scratch assay, cck8 assay and cell adhesion assay showed that SLC7A1 highly expressed in CAFs promoted tumor cells invasion, migration and metastasis in vitro. The effect of SLC7A1 on MAPK and EMT pathway proteins in ovarian cancer (OC) was verified by RNA sequencing and western blotting. Overexpression of SLC7A1 in OC is involved in MAPK/ ERK pathway and EMT. In general, in HGSOC, CAFs overexpressing SLC7A1 supported the migration and invasion of tumor cells; SLC7A1 is highly expressed in ovarian cancer and is involved in ERK phosphorylation and EMT signaling in MAPK signaling pathway. This suggests that SLC7A1 may be a potential therapeutic target for OC metastasis.

Riboflavin protects against pancreatic cancer metastasis by targeting TGF-β receptor 1

The inhibition of transforming growth factor-β1 (TGF-β1) signaling by targeting TGF-β receptor 1 (TβR1) has been considered as an ideal approach for the prevention of pancreatic cancer metastasis. Utilizing a pharmacophore model for TβR1 inhibitors, candidate compounds with the potential TβR1 binding ability were screened from the U.S. Food and Drug Administration (FDA) database, and riboflavin (RF) with a highest fit value was chosen to investigate its binding ability to TβR1 and effect on TGF-β1 signaling in pancreatic cancer cells. Molecular docking and cellular thermal shift assay (CETSA) proved that RF at pharmacological concentrations could directly bind to TβR1. Further studies showed that pharmacological concentrations of RF in vitro could block TGF-β1 signaling, suppress the migration and invasion, and prevent epithelial-mesenchymal transition (EMT) process of pancreatic cancer cells in the absence or presence of TGF-β1 stimulation, indicating that RF presented anti-metastatic effect in pancreatic cancer cells. Knockdown of TβR1 could significantly attenuate the effects of RF on the migration and EMT process in pancreatic cancer cells, further confirming that the anti-metastatic effect of RF was achieved by blocking TGF-β1 signaling after binding to TβR1. Moreover, in a mouse model of pancreatic cancer metastasis, it was certified that RF administration could block lung and liver metastases, TGF-β1 signaling and EMT process of pancreatic cancer in vivo. In summary, our findings showed that RF could block TGF-β1 signaling by directly binding to TβR1, thereby suppressing the metastasis of pancreatic cancer cells by inhibiting EMT process both in vitro and in vivo.