Transforming growth factor-β signaling: From tissue fibrosis to therapeutic opportunities

Transposon-based oncogene integration in Abcb4(Mdr2)-/- mice recapitulates high susceptibility to cholangiocarcinoma in primary sclerosing cholangitis

BACKGROUND & AIMS

Cholangiocarcinoma (CCA) is a dreaded complication of primary sclerosing cholangitis (PSC) that is difficult to diagnose and associated with high mortality. A lack of animal models of CCA recapitulating the hepatic microenvironment of sclerosing cholangitis has hindered the development of novel treatments. Herein, we sought to develop a mouse model of PSC-associated CCA.

METHODS

Ten-week-old Mdr2-/- mice with congenital PSC-like disease, and healthy wild-type littermates were subjected to either modified retrograde biliary instillation or hydrodynamic tail vein injection of a sleeping beauty transposon-transposase plasmid system with activated AKT (myr-AKT) and Yap (YapS127A) proto-oncogenes (SB AKT/YAP1). The role of TGFβ was interrogated via ALK5 inhibitor (SB-525334) administration. Tumor phenotype, burden and desmoplastic reaction were analyzed histologically and via RNA sequencing.

RESULTS

While SB AKT/YAP1 plasmids administered via retrograde biliary injection caused tumors in Mdr2-/-, only 26.67% (4/15) of these tumors were CCA. Alternatively, hydrodynamic tail vein injection of SB AKT/YAP1 resulted in robust tumorigenesis in all fibrotic Mdr2-/- mice with high CCA burden compared to healthy mice. Tumors phenotypically resembled human CCA, expressed multiple CCA (but not hepatocellular carcinoma) markers, and exhibited a profound desmoplastic reaction. RNA sequencing analysis revealed profound transcriptional changes in CCA evolving in a PSC-like context, with specific alterations in multiple immune pathways. Pharmacological TGFβ inhibition led to enhanced immune cell tumor infiltration, reduced tumor burden and suppressed desmoplastic collagen accumulation compared to placebo.

CONCLUSION

We established a new high-fidelity cholangiocarcinoma model in mice, termed SB CCA.Mdr2-/-, which recapitulates the increased susceptibility to CCA in the setting of biliary injury and fibrosis observed in PSC. Through transcriptomics and pharmacological studies, we show dysregulation of multiple immune pathways and TGFβ signaling as potential drivers of CCA in a PSC-like microenvironment.

IMPACT AND IMPLICATIONS

Animal models for primary sclerosing cholangitis (PSC)-related cholangiocarcinoma (PSC-CCA) are lacking. Thus, we have developed and characterized a new mouse model of PSC-CCA, termed SB CCA.Mdr2-/-, which features reliable tumor induction on a PSC-like background of biliary injury and fibrosis. Global gene expression alterations were identified and standardized tools, including automated whole slide image analysis methodology for tumor burden and feature analysis, were established to enable systematic research into PSC-CCA biology and formal preclinical drug testing.

Chlorogenic acid alleviates renal fibrosis by reducing lipid accumulation in diabetic kidney disease through suppressing the Notch1 and Stat3 signaling pathway

AIMS

Abnormal renal lipid metabolism causes renal lipid deposition, which leads to the development of renal fibrosis in diabetic kidney disease (DKD). The aim of this study was to investigate the effect and mechanism of chlorogenic acid (CA) on reducing renal lipid accumulation and improving DKD renal fibrosis.

METHODS

This study evaluated the effects of CA on renal fibrosis, lipid deposition and lipid metabolism by constructing in vitro and in vivo models of DKD, and detected the improvement of Notch1 and Stat3 signaling pathways. Molecular docking was used to predict the binding between CA and the extracellular domain NRR1 of Notch1 protein.

RESULTS

In vitro studies have shown that CA decreased the expression of Fibronectin, α-smooth muscle actin (α-SMA), p-smad3/smad3, alleviated lipid deposition, promoted the expression of carnitine palmitoyl transferase 1 A (CPT1A), and inhibited the expression of cholesterol regulatory element binding protein 1c (SREBP1c). The expression of Notch1, Cleaved Notch1, Hes1, and p-stat3/stat3 were inhibited. These results suggested that CA might reduce intercellular lipid deposition in human kidney cells (HK2) by inhibiting Notch1 and stat3 signaling pathways, thereby improving fibrosis. Further, in vivo studies demonstrated that CA improved renal fibrosis and renal lipid deposition in DKD mice by inhibiting Notch1 and stat3 signaling pathways. Finally, molecular docking experiments showed that the binding energy of CA and NRR1 was -6.6 kcal/mol, which preliminarily predicted the possible action of CA on Notch1 extracellular domain NRR1.

CONCLUSION

CA reduces renal lipid accumulation and improves DKD renal fibrosis by inhibiting Notch1 and stat3 signaling pathways.

TRIM65 deficiency alleviates renal fibrosis through NUDT21-mediated alternative polyadenylation

Chronic kidney disease (CKD) is a major global health concern and the third leading cause of premature death. Renal fibrosis is the primary process driving the progression of CKD, but the mechanisms behind it are not fully understood, making treatment options limited. Here, we find that the E3 ligase TRIM65 is a positive regulator of renal fibrosis. Deletion of TRIM65 results in a reduction of pathological lesions and renal fibrosis in mouse models of kidney fibrosis induced by unilateral ureteral obstruction (UUO)- and folic acid. Through screening with a yeast-hybrid system, we identify a new interactor of TRIM65, the mammalian cleavage factor I subunit CFIm25 (NUDT21), which plays a crucial role in fibrosis through alternative polyadenylation (APA). TRIM65 interacts with NUDT21 to induce K48-linked polyubiquitination of lysine 56 and proteasomal degradation, leading to the inhibition of TGF-β1-mediated SMAD and ERK1/2 signaling pathways. The degradation of NUDT21 subsequently altered the length and sequence content of the 3'UTR (3'UTR-APA) of several pro-fibrotic genes including Col1a1, Fn-1, Tgfbr1, Wnt5a, and Fzd2. Furthermore, reducing NUDT21 expression via hydrodynamic renal pelvis injection of adeno-associated virus 9 (AAV9) exacerbated UUO-induced renal fibrosis in the normal mouse kidneys and blocked the protective effect of TRIM65 deletion. These findings suggest that TRIM65 promotes renal fibrosis by regulating NUDT21-mediated APA and highlight TRIM65 as a potential target for reducing renal fibrosis in CKD patients.

Poria cocos: traditional uses, triterpenoid components and their renoprotective pharmacology

Poria cocos and its surface layer of Poria cocos (Schw.) Wolf (Polyporaceae), are used in traditional Chinese medicine for its diuretic and renoprotective effects. Phytochemical studies have shown that lanostane and 3,4-seco-lanostane tetracyclic triterpenoids are the main components of P. cocos and its surface layer. Accumulating evidence shows that triterpenoid components in P. cocos and its surface layer contribute to their renoprotective effect. The surface layer of P. cocos showed a stronger diuretic effect than P. cocos. The ethanol extract of the surface layer and its components improved acute kidney injury, acute kidney injury-to-chronic kidney disease transition and chronic kidney disease such as diabetic kidney disease, nephrotic syndrome and tubulointerstitial nephropathy, and protected against renal fibrosis. It has been elucidated that P. cocos and its surface layer exert a diuretic effect and improve kidney diseases through a variety of molecular mechanisms such as aberrant pathways TGF-β1/Smad, Wnt/β-catenin, IκB/NF-κB and Keap1/Nrf2 signaling as well as the activation of renin-angiotensin system, matrix metalloproteinases, aryl hydrocarbon receptor and endogenous metabolites. These studies further confirm the renoprotective effect of P. cocos and its surface layer and provide a beneficial basis to its clinical use in traditional medicine.

Jiawei Taohe Chengqi Decoction attenuates CCl4 induced hepatic fibrosis by inhibiting HSCs activation via TGF-β1/CUGBP1 and IFN-γ/Smad7 pathway

BACKGROUND

Hepatic fibrosis (HF) is an essential stage in the progression of different chronic liver conditions to cirrhosis and even hepatocellular carcinoma. The activation of hepatic stellate cells (HSCs) plays a crucial role in the progression of HF. IFN- γ/Smad7 pathway can inhibit HSCs activation, while TGF-β1/CUGBP1 pathway can inhibit IFN-γ/Smad7 pathway transduction and promote HSCs activation. Thus, inhibiting the TGF-β1/CUGBP1 pathway and activating the IFN-γ/Smad7 pathway reverses HSCs activation and inhibits HF. Jiawei Taohe Chengqi Decoction (JTCD) was derived from the Taohe Chengqi Tang in the ancient Chinese medical text titled "Treatise on Febrile Diseases". We found several anti-HF components in JTCD including ginsenoside Rb1 and others, but the specific mechanism of anti-HF in JTCD is not clear.

PURPOSE

To elucidate the specific mechanism by which JTCD reverses HF by inhibiting the activation of HSCs, and to establish a scientific foundation for treating HF with Traditional Chinese medicine (TCM).

METHODS

We constructed a CCl4-induced mice HF model in vivo and activated human hepatic stellate cell line (LX-2) with TGF-β1 in vitro, after which they were treated with JTCD and the corresponding inhibitors. We examined the expression of pivotal molecules in the two pathways mentioned above by immunofluorescence staining, Western blotting and RT-PCR.

RESULTS

JTCD attenuated liver injury and reduced serum ALT and AST levels in mice. In addition, JTCD attenuated CCl4-induced HF by decreasing the expression of α-SMA, COL1A1 and other markers of HSCs activation in mice liver tissue. Moreover, JTCD effectively suppressed the levels of TGF-β1, p-Smad3, p-p38MAPK, p-ATF2, and CUGBP1 in vivo and in vitro and upregulated the levels of IFN-γ, p-STAT1, and Smad7. Mechanically, after using the inhibitors of both pathways in vitro, we found that JTCD inhibited the activation of HSCs by restoring the balance of the TGF-β1/CUGBP1 and IFN-γ/Smad7 pathways.

CONCLUSION

We demonstrated that JTCD inhibited HSCs activation and reversed HF by inhibiting the TGF-β1/CUGBP1 signalling pathway and upregulating the IFN-γ/Smad7 signalling pathway. Moreover, we have identified specific links where JTCD interferes with both pathways to inhibit HSCs activation. JTCD is an effective candidate for the clinical treatment of HF.

Iron-laden macrophage-mediated paracrine profibrotic signaling induces lung fibroblast activation

Idiopathic pulmonary fibrosis (IPF) is a devastating condition characterized by progressive lung scarring and uncontrolled fibroblast proliferation, inevitably leading to organ dysfunction and mortality. Although elevated iron levels have been observed in patients and animal models of lung fibrosis, the mechanisms linking iron dysregulation to lung fibrosis pathogenesis, particularly the role of macrophages in orchestrating this process, remain poorly elucidated. Here we evaluate iron metabolism in macrophages during pulmonary fibrosis using both in vivo and in vitro approaches. In murine bleomycin- and amiodarone-induced pulmonary fibrosis models, we observed significant iron deposition and lipid peroxidation in pulmonary macrophages. Intriguingly, the ferroptosis regulator glutathione peroxidase 4 (GPX4) was upregulated in pulmonary macrophages following bleomycin instillation, a finding corroborated by single-cell RNA sequencing analysis. Moreover, macrophages isolated from fibrotic mouse lungs exhibited increased transforming growth factor (TGF)-β1 expression that correlated with lipid peroxidation. In vitro, iron overload in bone marrow-derived macrophages triggered lipid peroxidation and TGF-β1 upregulation, which was effectively suppressed by ferroptosis inhibitors. When cocultured with iron-overloaded macrophages, lung fibroblasts exhibited heightened activation, evidenced by increased α-smooth muscle actin and fibronectin expression. Importantly, this profibrotic effect was attenuated by treating macrophages with a ferroptosis inhibitor or blocking TGF-β receptor signaling in fibroblasts. Collectively, our study elucidates a novel mechanistic paradigm in which the accumulation of iron within macrophages initiates lipid peroxidation, thereby amplifying TGF-β1 production, subsequently instigating fibroblast activation through paracrine signaling. Thus, inhibiting iron overload and lipid peroxidation warrants further exploration as a strategy to suppress fibrotic stimulation by disease-associated macrophages. NEW & NOTEWORTHY This study investigates the role of iron in pulmonary fibrosis, specifically focusing on macrophage-mediated mechanisms. Iron accumulation in fibrotic lung macrophages triggers lipid peroxidation and an upregulation of transforming growth factor (TGF)-β1 expression. Coculturing iron-laden macrophages activates lung fibroblasts in a TGF-β1-dependent manner, which can be mitigated by ferroptosis inhibitors. These findings underscore the potential of targeting iron overload and lipid peroxidation as a promising strategy to alleviate fibrotic stimulation provoked by disease-associated macrophages.

Structural impact, ligand-protein interactions, and molecular phenotypic effects of TGF-β1 gene variants: In silico analysis with implications for idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic Pulmonary Fibrosis (IPF) is a chronic interstitial lung disease resulting in progressively deteriorating lung function. Transforming growth factor-β1 (TGF-β1) belongs to the TGF superfamily and exerts a profibrotic role in promoting lung fibrosis by facilitating fibroblast infiltration and activity, extracellular matrix deposition, and inhibition of collagen breakdown, thus promoting tissue remodelling and IPF.

MATERIALS AND METHODS

We evaluated the link between pathogenic TGF-β1 SNPs and IPF pathogenesis and the structure-activity functional consequences of those SNPs on the TGF-β1 protein. Several computational algorithms were merged to address the functional consequences of TGF-β1 gene mutations to protein stability, putative post-translational modification sites, ligand-protein interactions, and molecular phenotypic effects. These included FATHMM, POLYPHEN2, PROVEAN, and SIFT tools (identifying deleterious nsSNPs in the TGF-β1 gene), along with Pmut, PhD-SNP, SNAP, MutPred and the related TMHMM, MARCOIL, and DisProt algorithms (predicting structural disorders). INPS-MD was also used to evaluate the mutation-induced TGF-β1 protein's stability and MODPRED for recognition of post-translational TGF-β1 modification.

RESULTS

In total, 14 major pathogenic variants markedly impact the destabilization of the TGF-β1 protein, with most of these high-risk mutations associated with decreased stability of the TGF-β1 protein as per the I-Mutant, MUpro, and INPS-MD tools. R205W, R185W, R180Q, D86Y, and I300T variants were proposed to participate in the post-translational modifications, thus affecting affect protein-ligand interactions. Furthermore, at-risk genetic variants appear to target conserved regions in the alpha helices, random coils, and extracellular loops, resulting in a varied composition of amino acids, charge, hydrophobicity, and spatial architecture.

CONCLUSIONS

This study manuscript comprehensively analyzes gene variants within the TGF-β1 gene, offering novel insights into their structural and functional implications in interacting with target sites. This study is significant for the development of targeted therapeutic strategies and personalized treatment approaches for patients with inflammatory lung diseases such as IPF.

Early growth response protein 2 promotes partial epithelial-mesenchymal transition by phosphorylating Smad3 during renal fibrosis

Chronic kidney disease (CKD) is a serious health problem worldwide, which ultimately leads to end-stage renal disease (ESRD). Renal fibrosis is the common pathway and major pathological manifestation for various CKD proceeding to ESRD. However, the underlying mechanisms and effective therapies are still ambiguous. Early growth response 2 (EGR2) is reportedly involved in organ formation and cell differentiation. To determine the role of EGR2 in renal fibrosis, we respectively confirmed the increased expression of EGR2 in kidney specimens from both CKD patients and mice with location in proximal tubules. Genetic deletion of EGR2 attenuated obstructive nephropathy while EGR2 overexpression further promoted renal fibrosis in mice subjected to unilateral ureteral obstruction (UUO) due to extracellular matrix (ECM) deposition mediating by partial epithelial-mesenchymal transition (EMT) as well as imbalance between matrix metalloproteinases (MMPs) and tissue inhibitor of MMPs (TIMPs). We found that EGR2 played a critical role in Smad3 phosphorylation, and inhibition of EGR2 reduced partial EMT leading to blockade of ECM accumulation in cultured human kidney 2 cells (HK2) treated with transforming growth factor β1 (TGF-β1). In addition, the transcription co-stimulator signal transducer and activator of transcription 3 (STAT3) phosphorylation was confirmed to regulate the transcription level of EGR2 in TGF-β1-induced HK2 cells. In conclusion, this study demonstrated that EGR2 played a pathogenic role in renal fibrosis by a p-STAT3-EGR2-p-Smad3 axis. Thus, targeting EGR2 could be a promising strategy for CKD treatment.

Immunomodulatory signalling networks in glioblastoma multiforme: a comprehensive review of therapeutic approaches

Glioblastoma multiforme is a very aggressive type of cancer with high mortality and poor prognosis worldwide. Advanced treatment options with an understanding of the molecules and signalling mechanisms involved in this type of cancer have the potential to increase targeted therapy and decrease off-target effects, resistance, and recurrence. Glioblastoma multiforme (GBM) presents a complex tumour microenvironment with numerous cellular components and an extracellular matrix comprising multiple components. A deeper understanding of these components and corresponding signalling pathways can increase the success of immune checkpoint inhibitors in the treatment of GBM. The discovery of specific molecular changes and biomarkers has led to the investigation of tailored treatments for individual patients. Combination therapies targeting multiple pathways or utilizing different modalities are emerging as a promising strategy albeit with challenges in drug delivery to the brain. The review presents a comprehensive update of the various immunomodulatory signalling networks in GBM and highlights the corresponding therapeutic approaches by targeting them.

Alantolactone alleviates epithelial-mesenchymal transition by regulating the TGF-β/STAT3 signaling pathway in renal fibrosis

Objective

The epithelial-to-mesenchymal transition (EMT) of renal tubular epithelial cells (RTECs) plays a crucial role in renal interstitial fibrosis and inflammation, which are key components of chronic kidney disease (CKD). Alantolactone, a selective inhibitor of signal transducer and activator of transcription 3 (STAT3), is used in Chinese herbal medicine. Despite its use, the effects of alnatolactone on EMT of RTECs has not been fully elucidated.

Methods

In this study, we investigated the potential of alantolactone to EMT in vivo and in vitro. Our experiments were performed using a unilateral ureteral obstruction (UUO) models and HK-2 cells, RTECs, treated with transforming growth factor (TGF-β).

Results

Alantolactone decreased tubular injury and reduced the expression of vimentin, a key EMT marker, while increasing E-cadherin expression in UUO kidneys. Similarly, in RTECs, alantolactone inhibited TGF-β-induced EMT and its markers. Furthermore, alantolactone attenuated UUO- and TGF-β-induced STAT3 phosphorylation both in vivo and in vitro, and inhibited the expression of TWIST, an EMT transcription factor, in both models.

Conclusion

Alantolactone improves EMT in RTECs by inhibiting STAT3 phosphorylation and Twist expression, suggesting its potential as a therapeutic agent for kidney fibrosis.

Intratracheal instillation of polyacrylic acid induced pulmonary fibrosis with elevated transforming growth factor-β1 and connective tissue growth factor

We investigated the intratracheal instillation of Polyacrylic acid (PAA) in rats to determine if it would cause pulmonary disorders, and to see what factors would be associated with the pathological changes. Male F344 rats were intratracheally instilled with low (0.2 mg/rat) and high (1.0 mg/rat) doses of PAA. They were sacrificed at 3 days, 1 week, 1 month, 3 months, and 6 months after PAA exposure to examine inflammatory and fibrotic changes in the lungs. There was a persistent increase in the neutrophil count, lactate dehydrogenase (LDH) levels, cytokine-induced neutrophil chemoattractant (CINC) values in bronchoalveolar lavage fluid (BALF), and heme oxygenase-1 (HO-1) in lung tissue. Transforming growth factor-beta 1 (TGF-β1), a fibrotic factor, showed a sustained increase in the BALF until 6 months after intratracheal instillation, and connective tissue growth factor (CTGF) in lung tissue was elevated at 3 days after exposure. Histopathological findings in the lung tissue showed persistent (more than one month) inflammation, fibrotic changes, and epithelial-mesenchymal transition (EMT) changes. There was also a strong correlation between TGF-β1 in the BALF and, especially, in the fibrosis score of histopathological specimens. Intratracheal instillation of PAA induced persistent neutrophilic inflammation, fibrosis, and EMT in the rats' lungs, and TGF-β1 and CTGF appeared to be associated with the persistent fibrosis.

Overexpression of COX7A1 Promotes the Resistance of Gastric Cancer to Oxaliplatin and Weakens the Efficacy of Immunotherapy

Gastric cancer (GC) is one of the most common clinical malignant tumors worldwide, with high morbidity and mortality. Presently, the overall response rate to immunotherapy is low, and current methods for predicting the prognosis of GC are not optimal. Therefore, novel biomarkers with accuracy, efficiency, stability, performance ratio, and wide clinical application are needed. Based on public data sets, the chemotherapy cohort and immunotherapy cohort from Sun Yat-sen University Cancer Center, a series of bioinformatics analyses, such as differential expression analysis, survival analysis, drug sensitivity prediction, enrichment analysis, tumor immune dysfunction and exclusion analysis, single-sample gene set enrichment analysis, stemness index calculation, and immune cell infiltration analysis, were performed for screening and preliminary exploration. Immunohistochemical staining and in vitro experiments were performed for further verification. Overexpression of COX7A1 promoted the resistance of GC cells to Oxaliplatin. COX7A1 may induce immune escape by regulating the number of fibroblasts and their cellular communication with immune cells. In summary, measuring the expression levels of COX7A1 in the clinic may be useful in predicting the prognosis of GC patients, the degree of chemotherapy resistance, and the efficacy of immunotherapy.

Bile acid metabolism in health and ageing-related diseases

Bile acids (BAs) have surpassed their traditional roles as lipid solubilizers and regulators of BA homeostasis to emerge as important signalling molecules. Recent research has revealed a connection between microbial dysbiosis and metabolism disruption of BAs, which in turn impacts ageing-related diseases. The human BAs pool is primarily composed of primary BAs and their conjugates, with a smaller proportion consisting of secondary BAs. These different BAs exert complex effects on health and ageing-related diseases through several key nuclear receptors, such as farnesoid X receptor and Takeda G protein-coupled receptor 5. However, the underlying molecular mechanisms of these effects are still debated. Therefore, the modulation of signalling pathways by regulating synthesis and composition of BAs represents an interesting and novel direction for potential therapies of ageing-related diseases. This review provides an overview of synthesis and transportion of BAs in the healthy body, emphasizing its dependence on microbial community metabolic capacity. Additionally, the review also explores how ageing and ageing-related diseases affect metabolism and composition of BAs. Understanding BA metabolism network and the impact of their nuclear receptors, such as farnesoid X receptor and G protein-coupled receptor 5 agonists, paves the way for developing therapeutic agents for targeting BA metabolism in various ageing-related diseases, such as metabolic disorder, hepatic injury, cardiovascular disease, renal damage and neurodegenerative disease.

Impaired Tertiary Dentin Secretion after Shallow Injury in Tgfbr2-Deficient Dental Pulp Cells Is Rescued by Extended CGRP Signaling

The transforming growth factor β (TGFβ) superfamily is a master regulator of development, adult homeostasis, and wound repair. Dysregulated TGFβ signaling can lead to cancer, fibrosis, and musculoskeletal malformations. We previously demonstrated that TGFβ receptor 2 (Tgfbr2) signaling regulates odontoblast differentiation, dentin mineralization, root elongation, and sensory innervation during tooth development. Sensory innervation also modulates the homeostasis and repair response in adult teeth. We hypothesized that Tgfbr2 regulates the neuro-pulpal responses to dentin injury. To test this, we performed a shallow dentin injury with a timed deletion of Tgfbr2 in the dental pulp mesenchyme of mice and analyzed the levels of tertiary dentin and calcitonin gene-related peptide (CGRP) axon sprouting. Microcomputed tomography imaging and histology indicated lower dentin volume in Tgfbr2cko M1s compared to WT M1s 21 days post-injury, but the volume was comparable by day 56. Immunofluorescent imaging of peptidergic afferents demonstrated that the duration of axon sprouting was longer in injured Tgfbr2cko compared to WT M1s. Thus, CGRP+ sensory afferents may provide Tgfbr2-deficient odontoblasts with compensatory signals for healing. Harnessing these neuro-pulpal signals has the potential to guide the development of treatments for enhanced dental healing and to help patients with TGFβ-related diseases.

Crocin's role in modulating MMP2/TIMP1 and mitigating hypoxia-induced pulmonary hypertension in mice

To explore the molecular pathogenesis of pulmonary arterial hypertension (PAH) and identify potential therapeutic targets, we performed transcriptome sequencing of lung tissue from mice with hypoxia-induced pulmonary hypertension. Our Gene Ontology analysis revealed that "extracellular matrix organization" ranked high in the biological process category, and matrix metallopeptidases (MMPs) and other proteases also played important roles in it. Moreover, compared with those in the normoxia group, we confirmed that MMPs expression was upregulated in the hypoxia group, while the hub gene Timp1 was downregulated. Crocin, a natural MMP inhibitor, was found to reduce inflammation, decrease MMPs levels, increase Timp1 expression levels, and attenuate hypoxia-induced pulmonary hypertension in mice. In addition, analysis of the cell distribution of MMPs and Timp1 in the human lung cell atlas using single-cell RNAseq datasets revealed that MMPs and Timp1 are mainly expressed in a population of fibroblasts. Moreover, in vitro experiments revealed that crocin significantly inhibited myofibroblast proliferation, migration, and extracellular matrix deposition. Furthermore, we demonstrated that crocin inhibited TGF-β1-induced fibroblast activation and regulated the pulmonary arterial fibroblast MMP2/TIMP1 balance by inhibiting the TGF-β1/Smad3 signaling pathway. In summary, our results indicate that crocin attenuates hypoxia-induced pulmonary hypertension in mice by inhibiting TGF-β1-induced myofibroblast activation.

miR-27b-3p reduces muscle fibrosis during chronic skeletal muscle injury by targeting TGF-βR1/Smad pathway

BACKGROUND

Fibrosis is a significant pathological feature of chronic skeletal muscle injury, profoundly affecting muscle regeneration. Fibro-adipogenic progenitors (FAPs) have the ability to differentiate into myofibroblasts, acting as a primary source of extracellular matrix (ECM). the process by which FAPs differentiate into myofibroblasts during chronic skeletal muscle injury remains inadequately explored.

METHOD

mouse model with sciatic nerve denervated was constructed and miRNA expression profiles between the mouse model and uninjured mouse were analyzed. qRT/PCR and immunofluorescence elucidated the effect of miR-27b-3p on fibrosis in vivo and in vitro. Dual-luciferase reporter identified the target gene of miR-27b-3p, and finally knocked down or overexpressed the target gene and phosphorylation inhibition of Smad verified the influence of downstream molecules on the abundance of miR-27b-3p and fibrogenic differentiation of FAPs.

RESULT

FAPs derived from a mouse model with sciatic nerves denervated exhibited a progressively worsening fibrotic phenotype over time. Introducing agomiR-27b-3p effectively suppressed fibrosis both in vitro and in vivo. MiR-27b-3p targeted Transforming Growth Factor Beta Receptor 1 (TGF-βR1) and the abundance of miR-27b-3p was negatively regulated by TGF-βR1/Smad.

CONCLUSION

miR-27b-3p targeting the TGF-βR1/Smad pathway is a novel mechanism for regulating fibrogenic differentiation of FAPs. Increasing abundance of miR-27b-3p, suppressing expression of TGF-βR1 and inhibiting phosphorylation of smad3 presented potential strategies for treating fibrosis in chronic skeletal muscle injury.

Homeostasis and evolution in relation to regeneration and repair

Homeostasis constitutes a key concept in physiology and refers to self-regulating processes that maintain internal stability when adjusting to changing external conditions. It diminishes internal entropy constituting a driving force behind evolution. Natural selection might act on homeostatic regulatory mechanisms and control mechanisms including homeodynamics, allostasis, hormesis and homeorhesis, where different stable stationary states are reached. Regeneration is under homeostatic control through hormesis. Damage to tissues initiates a response to restore the impaired equilibrium caused by mild stress using cell proliferation, cell differentiation and cell death to recover structure and function. Repair is a homeorhetic change leading to a new stable stationary state with decreased functionality and fibrotic scarring without reconstruction of the 3-D pattern. Mechanisms determining entrance of the tissue or organ to regeneration or repair include the balance between innate and adaptive immune cells in relation to cell plasticity and stromal stem cell responses, and redox balance. The regenerative and reparative capacities vary in different species, distinct tissues and organs, and at different stages of development including ageing. Many cell signals and pathways play crucial roles determining regeneration or repair by regulating protein synthesis, cellular growth, inflammation, proliferation, autophagy, lysosomal function, metabolism and metalloproteinase cell signalling. Attempts to favour the entrance of damaged tissues to regeneration in those with low proliferative rates have been made; however, there are evolutionary constraint mechanisms leading to poor proliferation of stem cells in unfavourable environments or tumour development. More research is required to better understand the regulatory processes of these mechanisms.

Promising nanotherapeutics of stem cell extracellular vesicles in liver regeneration

Extracellular vesicles (EVs) have gainedsignificant attention due totheir crucialroles invarious biological systems. This review aims to explore the functions of EVs in both in physiological and pathological states of the liver, with a specific focus on the potential mechanisms and concrete evidence of EVs in liver regeneration processes. The review begins by emphasizing the importance of EVs in maintaining liver health and their involvement in different pathological conditions, starting from the liver's own EVs. Reviewing the role of EVs in liver diseases to reveal the impact of EVs in pathological processes (e.g., hepatitis, liver fibrosis, and cirrhosis) and elucidate their signaling functions at the molecular level. Subsequently, the work concentrates on the functions of EVs in liver regeneration, revealing their key role in repair and regeneration following liver injury by carrying growth factors, nucleic acids, and other bioactive molecules. This part not only theoretically clarifies the mechanisms of EVs in liver regeneration but also experimentally demonstrates their role in promoting liver cell proliferation, inhibiting apoptosis, regulating immune responses, and fostering angiogenesis, laying the groundwork for future clinical applications. Moreover, this work provides a comprehensive analysis of the challenges faced by existing EV-based therapies in liver regeneration and offers prospects for future research directions. It highlights that despite the tremendous potential of EVs in treating liver diseases, there are still technical challenges (e.g., EV isolation and purification, dosage control, and targeted delivery). To overcome these challenges, the review suggests improvements to current technologies and the development of new methods to realize the clinical application of EVs in treating liver diseases.

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.

PD-1 Inhibitor Aggravate Irradiation-Induced Myocardial Fibrosis by Regulating TGF-β1/Smads Signaling Pathway via GSDMD-Mediated Pyroptosis

Cancer therapy has entered a new era with the use of programmed cell death protein 1 (PD-1) immune checkpoint inhibitors. When combined with thoracic radiotherapy, it demonstrates synergistic anti-tumor effects and potentially worsens radiation-induced myocardial fibrosis (RIMF). RIMF is the final stage of radiation-induced heart disease (RIHD) and a potentially fatal clinical complication of chest radiotherapy. It is characterized by decreased ventricular elasticity and distensibility, which can result in decreased ejection fraction, heart failure, and even sudden cardiac death. Pyroptosis, a type of programmed cell death, is mediated by members of the gasdermin (GSDM) family and has been associated with numerous cardiac disorders. The effect of pyroptosis on myocardial fibrosis caused by a combination of radiotherapy and PD-1 inhibitors remains uncertain. In this study, a 6MV X-ray of 20 Gy for local heart irradiation was used in the RIHD mouse model. We noticed that PD-1 inhibitors aggravated radiation-induced cardiac dysfunction and RIMF, concurrently enhancing the presence of CD8+ T lymphocytes in the cardiac tissue. Additionally, our findings indicated that the combination of PD-1 inhibitor and thoracic radiation can stimulate caspase-1 to cleave GSDMD, thereby regulating pyroptosis and liberating interleukin-8 (IL-18). In the myocardium of mice, the manifestation of pyroptosis mediated by GSDMD is accompanied by the buildup of proteins associated with fibrosis, such as collagen I, transforming growth factor β1 (TGF-β1), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and tumor necrosis factor α (TNF-α). Moreover, it was discovered that TFG-β1 induced the phosphorylation of Smad2/Smad3 when the cardiac underwent PD-1 inhibitor in conjunction with thoracic irradiation (IR). The findings of this research indicate that PD-1 inhibitor worsen RIMF in mice by triggering GSDMD-induced pyroptosis and influencing the TGF-β1/Smads pathway. While using the caspase-1 inhibitor Z-YVAD-FMK, RIMF can be alleviated. Blocking GSDMD may be a viable strategy for managing myocardial fibrosis caused by the combination of PD-1 inhibitors and radiotherapy.

Nephroprotective Effect of Bergapten Against Cyclophosphamide-Mediated Renal Stress, Inflammation, and Fibrosis in Wistar Rats: Probable Role of NF-kB and TGF-β1 Signaling Molecules

Cyclophosphamide (CPM) is a well-established antineoplastic drug with marked clinical outcomes in various types of cancers. Despite being a promising drug, its use is associated with significant renal toxicity and often limits its use, leading to compromised clinical outcomes. Therefore, this study explored the renal protective effect of bergapten (BGP), a natural bioactive compound that showed marked antioxidant, anti-inflammatory, anticancer, and neuroprotective effects. Till now, BGP has not been studied for its renal protective effect in an in vivo model. Animals were divided into control, toxic, BGP-3, BGP-10, and BGP Per se. The control group was treated with normal saline for 2 weeks. To the toxic group, CPM 200 mg/kg was given on day 7 as i.p. To BGP-3, 10, and Per se, BGP-3 and 10 mg/kg, ip was given 2 weeks with a single shot of CPM 200 day 7. To the Per se group, only BGP 10 mg/kg, ip was given from day 1 to day 14. After 14 days, animals were sacrificed, and kidneys were removed and studied for the markers of oxidative stress, inflammation, renal injury, renal fibrosis, and renal damage using biochemical, histopathological, and immunohistochemical studies. We found that BGP-10 effectively reversed the damage toward normal, whereas BGP-3 failed to exhibit a significant renal protective effect. We conclude that bergapten could be a potential renal protective drug, and hence, more detailed cellular molecular-based studies are needed to bring this drug from the bench to the bedside.

Interstitial lung disease: a review of classification, etiology, epidemiology, clinical diagnosis, pharmacological and non-pharmacological treatment

Interstitial lung diseases (ILDs) refer to a heterogeneous and complex group of conditions characterized by inflammation, fibrosis, or both, in the interstitium of the lungs. This results in impaired gas exchange, leading to a worsening of respiratory symptoms and a decline in lung function. While the etiology of some ILDs is unclear, most cases can be traced back to factors such as genetic predispositions, environmental exposures (including allergens, toxins, and air pollution), underlying autoimmune diseases, or the use of certain medications. There has been an increase in research and evidence aimed at identifying etiology, understanding epidemiology, improving clinical diagnosis, and developing both pharmacological and non-pharmacological treatments. This review provides a comprehensive overview of the current state of knowledge in the field of interstitial lung diseases.

Levels of Lysozyme and SLPI in Bronchoalveolar Lavage: Exploring Their Role in Interstitial Lung Disease

Interstitial lung diseases (ILDs) are characterized by inflammation or fibrosis of the pulmonary parenchyma. Despite the involvement of immune cells and soluble mediators in pulmonary fibrosis, the influence of antimicrobial peptides (AMPs) remains underexplored. These effector molecules display a range of activities, which include immunomodulation and wound repair. Here, we investigate the role of AMPs in the development of fibrosis in ILD. We compare the concentration of different AMPs and different cytokines in 46 fibrotic (F-ILD) and 17 non-fibrotic (NF-ILD) patients by ELISA and using peripheral blood mononuclear cells from in vitro stimulation in the presence of lysozyme or secretory leukocyte protease inhibitor (SLPI) from 10 healthy donors. We observed that bronchoalveolar lavage (BAL) levels of AMPs were decreased in F-ILD patients (lysozyme: p < 0.001; SLPI: p < 0.001; LL-37: p < 0.001; lactoferrin: p = 0.47) and were negatively correlated with levels of TGF-β (lysozyme: p = 0.02; SLPI: p < 0.001) and IL-17 (lysozyme: p < 0.001; SLPI: p < 0.001). We observed that lysozyme increased the percentage of CD86+ macrophages (p < 0.001) and the production of TNF-α (p < 0.001). We showed that lysozyme and SLPI were associated with clinical parameters (lysozyme: p < 0.001; SLPI: p < 0.001) and disease progression (lysozyme: p < 0.001; SLPI: p = 0.01). These results suggest that AMPs may play an important role in the anti-fibrotic response, regulating the effect of pro-fibrotic cytokines. In addition, levels of lysozyme in BAL may be a potential biomarker to predict the progression in F-ILD patients.

Cell Senescence-Independent Changes of Human Skin Fibroblasts with Age

Skin ageing is defined, in part, by collagen depletion and fragmentation that leads to a loss of mechanical tension. This is currently believed to reflect, in part, the accumulation of senescent cells. We compared the expression of genes and proteins for components of the extracellular matrix (ECM) as well as their regulators and found that in vitro senescent cells produced more matrix metalloproteinases (MMPs) than proliferating cells from adult and neonatal donors. This was consistent with previous reports of senescent cells contributing to increased matrix degradation with age; however, cells from adult donors proved significantly less capable of producing new collagen than neonatal or senescent cells, and they showed significantly lower myofibroblast activation as determined by the marker α-SMA. Functionally, adult cells also showed slower migration than neonatal cells. We concluded that the increased collagen degradation of aged fibroblasts might reflect senescence, the reduced collagen production likely reflects senescence-independent processes.

Altered serum cytokines in patients with symptomatic disk herniation and depressive symptoms

Purpose

An increasing number of studies have indicated the important role of cytokines in the development of depressive disturbances (DD). In medically ill patients, cytokines can provoked sickness behavior, the signs of which resemble DD. This results in alterations in behavior to limit energy expenditure and redirect it to cope with particular diseases. The aim of our study was to investigate the role of pro-inflammatory IL-6, TNF-α, and IL-1β and anti-inflammatory IL-10 and TGF-β in DD observed in patients suffering from pain caused by disk herniation (DH) qualified for surgery.

Patients and methods

The intensity of DD assessed by using Beck Depression Inventory, pain intensity, and functional impairment were evaluated in 70 patients with DH who were qualified for surgery. Pro-inflammatory serum levels of TNF-α, IL-1, IL-6, anti-inflammatory TGF-β, and IL-10 were measured.

Results

Elevated serum levels of TGF-β, IL-10, and IL-6 were found in the group with moderate and severe depressive symptoms (SD) compared with the groups with mild (MD) or no depressive symptoms (ND). TGF-β levels were negatively correlated with pain intensity, as assessed using the Present Pain Intensity scale in SD. Functional impairment measured using the Oswestry Disability Index was the most advanced in SD group.

Conclusion

Results of our study can suggest association between depressive disturbances and anti-inflammatory cytokines TGF-β and IL-10. Functional impairment of SD group is more severe but serum levels of TGF-β and IL-10, which are involved in the healing processes, are increased.

Caffeic acid ethanolamide induces antifibrosis, anti-inflammatory, and antioxidant effects protects against bleomycin-induced pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease; its cause is unknown, and it leads to notable health problems. Currently, only two drugs are recommended for IPF treatment. Although these drugs can mitigate lung function decline, neither can improve nor stabilize IPF or the symptoms perceived by patients. Therefore, the development of novel treatment options for pulmonary fibrosis is required. The present study investigated the effects of a novel compound, caffeic acid ethanolamide (CAEA), on human pulmonary fibroblasts and evaluated its potential to mitigate bleomycin-induced pulmonary fibrosis in mice. CAEA inhibited TGF-β-induced α-SMA and collagen expression in human pulmonary fibroblasts, indicating that CAEA prevents fibroblasts from differentiating into myofibroblasts following TGF-β exposure. In animal studies, CAEA treatment efficiently suppressed immune cell infiltration and the elevation of TNF-α and IL-6 in bronchoalveolar lavage fluid in mice with bleomycin-induced pulmonary fibrosis. Additionally, CAEA exerted antioxidant effects by recovering the enzymatic activities of oxidant scavengers. CAEA directly inhibited activation of TGF-β receptors and protected against bleomycin-induced pulmonary fibrosis through inhibition of the TGF-β/SMAD/CTGF signaling pathway. The protective effect of CAEA was comparable to that of pirfenidone, a clinically available drug. Our findings support the potential of CAEA as a viable method for preventing the progression of pulmonary fibrosis.

Sevelamer reverses liver fibrosis by deactivation of hepatic stellate cells

Liver fibrosis is a chronic liver disease characterized by a progressive wound healing response caused by chronic liver injury. Currently, there are no approved clinical treatments for liver fibrosis. Sevelamer is used clinically to treat hyperphosphatemia and has shown potential therapeutic effects on liver diseases. However, there have been few studies evaluating the therapeutic effects of sevelamer on liver fibrosis, and the specific mechanisms are still unclear. In this study, we investigated the antifibrotic effects of sevelamer-induced low inorganic phosphate (Pi) stress in vitro and in vivo and analyzed the detailed mechanisms. We found that low Pi stress could inhibit the proliferation of activated hepatic stellate cells (HSCs) by promoting apoptosis, effectively suppressing the migration and epithelial-mesenchymal transition (EMT) of hepatic stellate cells. Additionally, low Pi stress significantly increased the antioxidant stress response. It is worth noting that low Pi stress indirectly inhibited the activation and migration of HSCs by suppressing transforming growth factor β (TGF-β) expression in macrophages. In a rat model of liver fibrosis, oral administration of sevelamer significantly decreased blood phosphorus levels, improved liver function, reduced liver inflammation, and increased the antioxidant stress response in the liver. Our study revealed that the key mechanism by which sevelamer inhibited liver fibrosis involved binding to gastrointestinal phosphate, resulting in a decrease in blood phosphorus levels, the downregulation of TGF-β expression in macrophages, and the inhibition of HSC migration and fibrosis-related protein expression. Therefore, our results suggest that sevelamer-induced low Pi stress can attenuate hepatic stellate cell activation and inhibit the progression of liver fibrosis, making it a potential option for the treatment of liver fibrosis and other refractory chronic liver diseases.

Clinico-radiological outcome of Arthroscopic Anterior Cruciate Ligament Reconstruction with Augmentation of Dehydrated Human Amnion Chorion Allograft Membrane using Peroneus Longus Autograft

Introduction

For many sportsmen, anterior cruciate ligament (ACL) tears are unfortunate but common injuries. Several growth factors, cytokine, chemokine, and protease inhibitors functions in stimulation of paracrine reactions in fibroblast, endothelial, and stem cells thereby promoting the tissue restorative processes. Augmented with dehydrated Human Amnion Chorion Membrane (dHACM) allograft reinforces the reconstructed ligament and aids in effective restoration.

Materials and methods

In this case control study 15 patients undertaking ACL reconstruction with tripled peroneus augmented dHACM (G1) were prospectively monitored up for a period of 8 months along with 15 control patients (G2) without dHACM augmentation. Clinical and radiological outcomes were analysed and assessed about effect of augmenting the peroneus longus graft using dHACM. Clinical analysis included pre-operative two, four, six, and eight months post-operative Tegnor-Lysholm score, and radiological analysis included the 6th month postoperative MRI signal-to-noise ratio (SNR) measurements by mean signal-value at femoral insertion, midsubstance and tibial insertion of ACL graft.

Results

Clinically, as a mean Lysholm score of all patients, they were revealed to be consecutively high in G1 than in Group 2 at four, six, and eight months. The signal-to-noise ratio from the MRI results showed majority having good healing in G1 group.

Conclusions

Based on 6-month MRI, an effective ligamentization (SNR<75) was noticed in 53.33% of patients in the dHACM allograft enhanced group on comparison with 33% in the controls. The overall results show that the augmentation of dHACM allograft to ACL reconstruction yields in good patient outcomes at post-operative follow-up.

Integrated Molecular and Histological Insights for Targeted Therapies in Mesenchymal Sinonasal Tract Tumors

PURPOSE OF REVIEW

This review aims to provide a comprehensive overview of mesenchymal sinonasal tract tumors (STTs), a distinct subset of STTs. Despite their rarity, mesenchymal STTs represent a unique clinical challenge, characterized by their rarity, often slow progression, and frequently subtle or overlooked symptoms. The complex anatomy of the sinonasal area, which includes critical structures such as the orbit, brain, and cranial nerves, further complicates surgical treatment options. This underscores an urgent need for more advanced and specialized therapeutic approaches.

RECENT FINDINGS

Advancements in molecular diagnostics, particularly in next-generation sequencing, have significantly enhanced our understanding of STTs. Consequently, the World Health Organization has updated its tumor classification to better reflect the distinct histological and molecular profiles of these tumors, as well as to categorize mesenchymal STTs with greater accuracy. The growing understanding of the molecular characteristics of mesenchymal STTs opens new possibilities for targeted therapeutic interventions, marking a significant shift in treatment paradigms. This review article concentrates on mesenchymal STTs, specifically addressing sinonasal tract angiofibroma, sinonasal glomangiopericytoma, biphenotypic sinonasal sarcoma, and skull base chordoma. These entities are marked by unique histopathological and molecular features, which challenge conventional treatment approaches and simultaneously open avenues for novel targeted therapies. Our discussion is geared towards delineating the molecular underpinnings of mesenchymal STTs, with the objective of enhancing therapeutic strategies and addressing the existing shortcomings in the management of these intricate tumors.

Reduction of renal interstitial fibrosis by targeting Tie2 in vascular endothelial cells

BACKGROUND

Tie2, a functional angiopoietin receptor, is expressed in vascular endothelial cells and plays an important role in angiogenesis and vascular stability. This study aimed to evaluate the effects of an agonistic Tie2 signal on renal interstitial fibrosis (RIF) and elucidate the underlying mechanisms.

METHODS

We established an in vivo mouse model of folic acid-induced nephropathy (FAN) and an in vitro model of lipopolysaccharide-stimulated endothelial cell injury, then an agonistic Tie2 monoclonal antibody (Tie2 mAb) was used to intervent these processes. The degree of tubulointerstitial lesions and related molecular mechanisms were determined by histological assessment, immunohistochemistry, western blotting, and qPCR.

RESULTS

Tie2 mAb attenuated RIF and reduced the level of fibroblast-specific protein 1 (FSP1). Further, it suppressed vascular cell adhesion molecule-1 (VCAM-1) and increased CD31 density in FAN. In the in vitro model, Tie2 mAb was found to decrease the expression of VCAM-1, Bax, and α-smooth muscle actin (α-SMA).

CONCLUSIONS

The present findings indicate that the agonistic Tie2 mAb exerted vascular protective effects and ameliorated RIF via inhibition of vascular inflammation, apoptosis, and fibrosis. Therefore, Tie2 may be a potential target for the treatment of this disease.

IMPACT

This is the first report to confirm that an agonistic Tie2 monoclonal antibody can reduce renal interstitial fibrosis in folic acid-induced nephropathy in mice. This mechanism possibly involves vascular protective effects brought about by inhibition of vascular inflammation, apoptosis and fibrosis. Our data show that Tie2 signal may be a novel, endothelium-specific target for the treatment of tubulointerstitial fibrosis.

Targeted inhibition of transforming growth factor-β type I receptor by AZ12601011 improves paraquat poisoning-induced multiple organ fibrosis

Paraquat (PQ) causes fatal poisoning that leads to systemic multiple organ fibrosis, and transforming growth factor (TGF)-β1 plays a critical role in this process. In this study, we aimed to investigate the effects of AZ12601011 (a small molecular inhibitor of TGFβRI) on PQ-induced multiple organ fibrosis. We established a mouse model of PQ in vivo and used PQ-treated lung epithelial cell (A549) and renal tubular epithelial cells (TECs) in vitro. Haematoxylin-eosin and Masson staining revealed that AZ12601011 ameliorated pulmonary, hepatic, and renal fibrosis, consistent with the decrease in the levels of fibrotic indicators, alpha-smooth muscle actin (α-SMA) and collagen-1, in the lungs and kidneys of PQ-treated mice. In vitro data showed that AZ12601011 suppressed the induction of α-SMA and collagen-1 in PQ-treated A549 cells and TECs. In addition, AZ12601011 inhibited the release of inflammatory factors, interleukin (IL)-1β, IL-6, and tumour necrosis factor-α. Mechanistically, TGF-β and TGFβRI levels were significantly upregulated in the lungs and kidneys of PQ-treated mice. Cellular thermal shift assay and western blotting revealed that AZ12601011 directly bound with TGFβRI and blocked the activation of Smad3 downstream. In conclusion, our findings revealed that AZ12601011 attenuated PQ-induced multiple organ fibrosis by blocking the TGF-β/Smad3 signalling pathway, suggesting its potential for PQ poisoning treatment.

The Upregulation of Leucine-Rich Repeat Containing 1 Expression Activates Hepatic Stellate Cells and Promotes Liver Fibrosis by Stabilizing Phosphorylated Smad2/3

Liver fibrosis poses a significant global health risk due to its association with hepatocellular carcinoma (HCC) and the lack of effective treatments. Thus, the need to discover additional novel therapeutic targets to attenuate liver diseases is urgent. Leucine-rich repeat containing 1 (LRRC1) reportedly promotes HCC development. Previously, we found that LRRC1 was significantly upregulated in rat fibrotic liver according to the transcriptome sequencing data. Herein, in the current work, we aimed to explore the role of LRRC1 in liver fibrosis and the underlying mechanisms involved. LRRC1 expression was positively correlated with liver fibrosis severity and significantly elevated in both human and murine fibrotic liver tissues. LRRC1 knockdown or overexpression inhibited or enhanced the proliferation, migration, and expression of fibrogenic genes in the human hepatic stellate cell line LX-2. More importantly, LRRC1 inhibition in vivo significantly alleviated CCl4-induced liver fibrosis by reducing collagen accumulation and hepatic stellate cells' (HSCs) activation in mice. Mechanistically, LRRC1 promoted HSC activation and liver fibrogenesis by preventing the ubiquitin-mediated degradation of phosphorylated mothers against decapentaplegic homolog (Smad) 2/3 (p-Smad2/3), thereby activating the TGF-β1/Smad pathway. Collectively, these results clarify a novel role for LRRC1 as a regulator of liver fibrosis and indicate that LRRC1 is a promising target for antifibrotic therapies.

Effects of low-level Er:YAG laser irradiation on proliferation and gene expression in primary gingival fibroblasts isolated from mouse maxilla

We investigated the effects of low-level Er:YAG laser irradiation on proliferation and alternations in early gene expression of gingival fibroblasts. Mice primary gingival fibroblasts were irradiated with an Er:YAG laser (1.8, 3.9, and 5.8 J/cm2 ). Irradiation at 3.9 J/cm2 promoted cell proliferation without significant changes in lactate dehydrogenase or Hspa1a expression. Three hours after irradiation at 3.9 J/cm2 , the Fn1 expression level was significantly increased. RNA-seq identified 15 differentially expressed genes between irradiated and non-irradiated cells, some of which belonged to immediate early genes (IEGs). Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated MAPK pathway enhancement, and gene set enrichment analysis showed enrichment in the TGF-β signaling gene set. Enhanced proliferation via laser irradiation disappeared upon inhibition of Dusp4, Dusp5, and Tgfr1 expression. Low-level Er:YAG laser irradiation, especially at 3.9 J/cm2 without a major temperature elevation, enhanced fibroblast proliferation, via TGF-β and the MAPK signaling pathway following IEG expression.

The ncRNA-TGF-β axis: Unveiling new frontiers in colorectal cancer research

Colorectal cancer (CRC) poses a substantial global challenge, necessitating a deeper understanding of the molecular underpinnings governing its onset and progression. The transforming growth factor beta (TGF-β) network has been a well-recognized cornerstone in advancing CRC. Nevertheless, a recent study has highlighted the growing importance of non-coding RNAs (ncRNAs) in this context. This comprehensive review aims to present an extensive examination of the interaction between ncRNAs and TGF-signaling. Noncoding RNAs (ncRNAs), encompassing circular RNAs (circRNAs), long-ncRNAs (lncRNAs), and microRNAs (miRNAs), have surfaced as pivotal modulators governing various aspects of TGF-β signaling. MiRNAs have been discovered to target elements within the TGF-β signaling, either enhancing or inhibiting signaling, depending on the context. LncRNAs have been associated with CRC progression, functioning as miRNA sponges or directly influencing TGF-β pathway elements. Even circRNAs, a relatively recent addition to the ncRNA family, have impacted CRC, affecting TGF-β signaling through diverse mechanisms. This review encompasses recent progress in comprehending specific ncRNAs involved in TGF-β signaling, their functional roles, and their clinical relevance in CRC. We investigate the possibility of ncRNAs as targets for detection, prognosis, and therapy. Additionally, we explore the interaction of TGF-β and other pathways in CRC and the role of ncRNAs within this intricate network. As we unveil the intricate regulatory function of ncRNAs in the TGF-β signaling in CRC, we gain valuable insights into the disease's pathogenesis. Incorporating these discoveries into clinical settings holds promise for more precise diagnosis, prognosis, and targeted therapeutic approaches, ultimately enhancing the care of CRC patients. This comprehensive review underscores the ever-evolving landscape of ncRNA research in CRC and the potential for novel interventions in the battle against this formidable disease.

Linking NLRP3 inflammasome and pulmonary fibrosis: mechanistic insights and promising therapeutic avenues

Pulmonary fibrosis is a devastating disorder distinguished by redundant inflammation and matrix accumulation in the lung interstitium. The early inflammatory cascade coupled with recurring tissue injury orchestrates a set of events marked by perturbed matrix hemostasis, deposition of matrix proteins, and remodeling in lung tissue. Numerous investigations have corroborated a direct correlation between the NLR family pyrin domain-containing 3 (NLRP3) activation and the development of pulmonary fibrosis. Dysregulated activation of NLRP3 within the pulmonary microenvironment exacerbates inflammation and may incite fibrogenic responses. Nevertheless, the precise mechanisms through which the NLRP3 inflammasome elicits pro-fibrogenic responses remain inadequately defined. Contemporary findings suggest that the pro-fibrotic consequences stemming from NLRP3 signaling primarily hinge on the action of interleukin-1β (IL-1β). IL-1β instigates IL-1 receptor signaling, potentiating the activity of transforming growth factor-beta (TGF-β). This signaling cascade, in turn, exerts influence over various transcription factors, including SNAIL, TWIST, and zinc finger E-box-binding homeobox 1 (ZEB 1/2), which collectively foster myofibroblast activation and consequent lung fibrosis. Here, we have connected the dots to illustrate how the NLRP3 inflammasome orchestrates a multitude of signaling events, including the activation of transcription factors that facilitate myofibroblast activation and subsequent lung remodeling. In addition, we have highlighted the prominent role played by various cells in the formation of myofibroblasts, the primary culprit in lung fibrosis. We also provided a concise overview of various compounds that hold the potential to impede NLRP3 inflammasome signaling, thus offering a promising avenue for the treatment of pulmonary fibrosis.

SIRT3/6: an amazing challenge and opportunity in the fight against fibrosis and aging

Fibrosis is a typical aging-related pathological process involving almost all organs, including the heart, kidney, liver, lung, and skin. Fibrogenesis is a highly orchestrated process defined by sequences of cellular response and molecular signals mechanisms underlying the disease. In pathophysiologic conditions associated with organ fibrosis, a variety of injurious stimuli such as metabolic disorders, epigenetic changes, and aging may induce the progression of fibrosis. Sirtuins protein is a kind of deacetylase which can regulate cell metabolism and participate in a variety of cell physiological functions. In this review, we outline our current understanding of common principles of fibrogenic mechanisms and the functional role of SIRT3/6 in aging-related fibrosis. In addition, sequences of novel protective strategies have been identified directly or indirectly according to these mechanisms. Here, we highlight the role and biological function of SIRT3/6 focus on aging fibrosis, as well as their inhibitors and activators as novel preventative or therapeutic interventions for aging-related tissue fibrosis.

Signaling pathways of liver regeneration: Biological mechanisms and implications

The liver possesses a unique regenerative ability to restore its original mass, in this regard, partial hepatectomy (PHx) and partial liver transplantation (PLTx) can be executed smoothly and safely, which has important implications for the treatment of liver disease. Liver regeneration (LR) can be the very complicated procedure that involves multiple cytokines and transcription factors that interact with each other to activate different signaling pathways. Activation of these pathways can drive the LR process, which can be divided into three stages, namely, the initiation, progression, and termination stages. Therefore, it is important to investigate the pathways involved in LR to elucidate the mechanism of LR. This study reviews the latest research on the key signaling pathways in the different stages of LR.

The nuclear factor kappa B signaling pathway is a master regulator of renal fibrosis

Renal fibrosis is increasingly recognized as a global public health problem. Acute kidney injury (AKI) and chronic kidney disease (CKD) both result in renal fibrosis. Oxidative stress and inflammation play central roles in progressive renal fibrosis. Oxidative stress and inflammation are closely linked and form a vicious cycle in which oxidative stress induces inflammation through various molecular mechanisms. Ample evidence has indicated that a hyperactive nuclear factor kappa B (NF-ƙB) signaling pathway plays a pivotal role in renal fibrosis. Hyperactive NF-ƙB causes the activation and recruitment of immune cells. Inflammation, in turn, triggers oxidative stress through the production of reactive oxygen species and nitrogen species by activating leukocytes and resident cells. These events mediate organ injury through apoptosis, necrosis, and fibrosis. Therefore, developing a strategy to target the NF-ƙB signaling pathway is important for the effective treatment of renal fibrosis. This Review summarizes the effect of the NF-ƙB signaling pathway on renal fibrosis in the context of AKI and CKD (immunoglobulin A nephropathy, membranous nephropathy, diabetic nephropathy, hypertensive nephropathy, and kidney transplantation). Therapies targeting the NF-ƙB signaling pathway, including natural products, are also discussed. In addition, NF-ƙB-dependent non-coding RNAs are involved in renal inflammation and fibrosis and are crucial targets in the development of effective treatments for kidney disease. This Review provides a clear pathophysiological rationale and specific concept-driven therapeutic strategy for the treatment of renal fibrosis by targeting the NF-ƙB signaling pathway.

H3K18 lactylation promotes the progression of arsenite-related idiopathic pulmonary fibrosis via YTHDF1/m6A/NREP

As epigenetic modifications, lactylation and N6-methyladenosine (m6A) have attracted wide attention. Arsenite is an environmental pollutant that has been proven to induce idiopathic pulmonary fibrosis (IPF). However, the molecular mechanisms of lactylation and m6A methylation are unclear in arsenite-related IPF (As-IPF). In view of the limited understanding of molecular mechanism of m6A and lactylation in As-IPF, MeRIP-seq, RNA-seq and ChIP-seq were analyzed to verify the target gene regulated by m6A and H3K18 lactylation (H3K18la). We found that, for As-IPF, the global levels of m6A, levels of YTHDF1 and m6A-modified neuronal protein 3.1 (NREP) were elevated in alveolar epithelial cells (AECs). The secretion levels of TGF-β1 were increased via YTHDF1/m6A/NREP, which promoted the fibroblast-to-myofibroblast transition (FMT). Further, extracellular lactate from myofibroblasts elevated levels of the global lactylation (Kla) and H3K18la via the lactate monocarboxylate transporter 1 (MCT1), and, in AECs, H3K18la facilitated the transcription of Ythdf1. This report highlights the role of crosstalk between AECs and myofibroblasts via lactylation and m6A and the significance of H3K18la regulation of YTHDF1 in the progression of As-IPF, which may be useful for finding effective therapeutic targets.

Flavokawain A ameliorates pulmonary fibrosis by inhibiting the TGF-β signaling pathway and CXCL12/CXCR4 axis

Idiopathic pulmonary fibrosis is a progressive fibrotic lung disease characterized by myofibroblast proliferation and extracellular matrix deposition that has a high mortality rate and limited therapeutic options. Flavokawain A(FKA) is the major component of chalcone in kava extract. FKA has been reported to inhibit TGF-β1-induced cardiomyocyte fibrosis by suppressing ROS production in A7r5 cells, but the role and mechanism of FKA in pulmonary fibrosis are unknown. In this study, we evaluated the effect of FKA on pulmonary fibrosis using an animal model of bleomycin-induced pulmonary fibrosis and showed that FKA alleviated the development of pulmonary fibrosis in a dose-dependent manner and improved lung function as well as collagen deposition and extracellular matrix accumulation in mice. In vitro studies showed that FKA inhibited myofibroblast activation and lung fibrosis progression by inhibiting TGF-β1/Smad signaling in a dose-dependent manner. In addition, we identified CXCL12 as a potential target of FKA through target prediction. Molecular docking, CETSA(cellular thermal displacement assay) and silver staining assays further demonstrated that FKA could interact with CXCL12 and that FKA could inhibit CXCL12 dimerization in vitro. Further analysis revealed that FKA could inhibit fibroblast activation and reduce extracellular matrix (ECM) production and collagen deposition by blocking CXCL12/CXCR4 signaling, and knocking down CXCR4 expression could weaken the inhibitory effect of FKA on CXCL12/CXCR4 signal transduction. In conclusion, our study showed that FKA inhibited CXCL12/CXCR4 signaling by inhibiting CXCL12 dimerization, blocked the CXCL12/CXCR4 signaling pathway and inhibited the TGF-β1-mediated signaling pathway to ameliorate pulmonary fibrosis, and FKA is a promising therapeutic agent for pulmonary fibrosis.

Effect of hydroalcoholic extract of Trigonella foenum-graecum leaves on wound healing in type 1 diabetic rats

Diabetes describes a group of metabolic disorders characterised by increased blood glucose concentration. People living with diabetes have a higher risk of morbidity and mortality than the general population. In 2015 it was estimated that there were 415 million (uncertainty interval: 340-536 million) people with diabetes aged 20-79 years, and 5.0 million deaths attributable to diabetes. When diabetic patients develop an ulcer, they become at high risk for major complications, including infection and amputation. The pathophysiologic relationship between diabetes and impaired healing is complex. Vascular, neuropathic, immune function, and biochemical abnormalities each contribute to the altered tissue repair. The use of herbal medicine has increased and attracted the attention of many researchers all over the world. In this study, we have evaluated the effect of 500mg/kg hydroalcoholic extract of Trigonella foenum-graecum leaves (TFG-E) on wound healing in diabetic rats using a full-thickness cutaneous incisional wound model. Wounds of treated animals showed better tensiometric indices, accelerated wound contraction, faster re-epithelialisation, improved neovascularisation, better modulation of fibroblasts and macrophage presence in the wound bed and moderate collagen formation.

Canagliflozin and irbesartan ameliorate renal fibrosis via the TGF-β1/Smad signaling pathway in Dahl salt-sensitive rats

OBJECTIVES

This study assessed the antifibrotic effects of canagliflozin, with or without irbesartan, on renal injury in Dahl salt-sensitive (SS) rats fed a high-salt (HS) diet.

METHODS

After the preconditioning stage, Dahl SS rats (n = 47) were divided into five experimental groups as follows: low-salt (LS, n = 7), HS (n = 10), HS with canagliflozin (n = 10), HS with irbesartan (n = 10), and HS with canagliflozin and irbesartan (n = 10).

RESULTS

The HS diet increased systolic blood pressure (SBP), renal fibrosis, fibrotic protein expression, and transforming growth factor-β1 (TGF-β1)/Smad2/3 pathway protein expression compared with the findings in the LS group. Irbesartan reduced SBP and slowed the loss of renal function. Canagliflozin significantly reduced body weight and renal fibrosis and suppressed the TGF-β1/Smad2/3 pathway. The combined therapy exerted better renoprotective effects on all outcome parameters.

CONCLUSIONS

These results indicate that canagliflozin and irbesartan exert different effects on renal injury in SS hypertensive rats, and the combined regimen could have stronger effects than either monotherapy.

Small artery remodeling and stiffening in deoxycorticosterone acetate-salt hypertensive rats involves the interaction between endogenous ouabain/Na + K + -ATPase/cSrc signaling

OBJECTIVE

Endogenous ouabain (EO) increases in some patients with hypertension and in rats with volume-dependent hypertension. When ouabain binds to Na + K + -ATPase, cSrc is activated, which leads to multieffector signaling activation and high blood pressure (BP). In mesenteric resistance arteries (MRA) from deoxycorticosterone acetate (DOCA)-salt rats, we have demonstrated that the EO antagonist rostafuroxin blocks downstream cSrc activation, enhancing endothelial function and lowering oxidative stress and BP. Here, we examined the possibility that EO is involved in the structural and mechanical alterations that occur in MRA from DOCA-salt rats.

METHODS

MRA were taken from control, vehicle-treated DOCA-salt or rostafuroxin (1 mg/kg per day, for 3 weeks)-treated DOCA-salt rats. Pressure myography and histology were used to evaluate the mechanics and structure of the MRA, and western blotting to assess protein expression.

RESULTS

DOCA-salt MRA exhibited signs of inward hypertrophic remodeling and increased stiffness, with a higher wall:lumen ratio, which were reduced by rostafuroxin treatment. The enhanced type I collagen, TGFβ1, pSmad2/3 Ser465/457 /Smad2/3 ratio, CTGF, p-Src Tyr418 , EGFR, c-Raf, ERK1/2 and p38MAPK protein expression in DOCA-salt MRA were all recovered by rostafuroxin.

CONCLUSION

A process combining Na + K + -ATPase/cSrc/EGFR/Raf/ERK1/2/p38MAPK activation and a Na + K + -ATPase/cSrc/TGF-1/Smad2/3/CTGF-dependent mechanism explains how EO contributes to small artery inward hypertrophic remodeling and stiffening in DOCA-salt rats. This result supports the significance of EO as a key mediator for end-organ damage in volume-dependent hypertension and the efficacy of rostafuroxin in avoiding remodeling and stiffening of small arteries.

Ellagic acid inhibits the formation of hypertrophic scars by suppressing TGF-β/Smad signaling pathway activity

Hypertrophic scar (HS) is a benign fibroproliferative skin disease, which lacks the ideal treatment and drugs. Ellagic acid (EA) is a natural polyphenol that prevents fibroblasts from proliferating and migrating. This study aimed to determine the role of EA in HS formation and its possible mechanism by in vitro experiments. HS fibroblasts (HSFs) and normal fibroblasts (NFs) were separated from HS tissue and normal skin tissue, respectively. HSFs were treated with 10 and 50 μM EA to assess their effect on HS formation. In particular, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and scratch assay were used to detect the viability and migration ability of HSFs. Quantitative reverse transcriptase real-time polymerase chain reaction was used to measure the mRNA expression level of basic fibroblast growth factor (bFGF), extracellular matrix (ECM)-related gene collagen-I (COL-I), and fibronectin 1 (FN1) in HSFs. Finally, Western blot was utilized to measure the expression level of TGF-β/Smad signaling pathway-related proteins in HSFs. The viability of HSFs was significantly increased compared with NFs. 10 and 50 μM EA treatment markedly inhibition the cell viability and migration of HSFs. EA treatment upregulated the bFGF expression level and downregulated the COL-I and FN1 expression level in HSFs. In addition, p-Smad2, p-Smad3, and transforming growth factor (TGF)-β1 expression levels as well as p-Smad2/Smad2 and p-Smad3/Smad3 ratios remarkably decreased in HSFs after EA treatment. EA inhibited the formation of HSs by suppressing the viability and migration of HSFs and ECM deposition as well as by preventing the activation of TGF-β/Smad signaling.

TGF-β as A Master Regulator of Aging-Associated Tissue Fibrosis

Fibrosis is the abnormal accumulation of extracellular matrix proteins such as collagen and fibronectin. Aging, injury, infections, and inflammation can cause different types of tissue fibrosis. Numerous clinical investigations have shown a correlation between the degree of liver and pulmonary fibrosis in patients and telomere length and mitochondrial DNA content, both of which are signs of aging. Aging involves the gradual loss of tissue function over time, which results in the loss of homeostasis and, ultimately, an organism's fitness. A major feature of aging is the accumulation of senescent cells. Senescent cells abnormally and continuously accumulate in the late stages of life, contributing to age-related fibrosis and tissue deterioration, among other aging characteristics. Furthermore, aging generates chronic inflammation, which results in fibrosis and decreases organ function. This finding suggests that fibrosis and aging are closely related. The transforming growth factor-beta (TGF-β) superfamily plays a crucial role in the physiological and pathological processes of aging, immune regulation, atherosclerosis, and tissue fibrosis. In this review, the functions of TGF-β in normal organs, aging, and fibrotic tissues is discussed: TGF-β signalling is altered with age and is an indicator of pathology associated with tissue fibrosis. In addition, this review discusses the potential targeting of noncoding.

Oxidative stress and inflammation are mediated via aryl hydrocarbon receptor signalling in idiopathic membranous nephropathy

Membranous nephropathy (MN) patients are diagnosed by the presence of phospholipase A2 receptor (PLA2R) before they progress to renal failure. However, the subepithelium-like immunocomplex deposit-mediated downstream molecular pathways are poorly understood. The aryl hydrocarbon receptor (AHR), NF-ƙB and Nrf2 pathways play central roles in the pathogenesis and progression of chronic kidney disease. However, their mutual effects on MN require further examination. Thus, we investigated the effect of AHR signalling on the NF-ƙB and Nrf2 pathways in IMN patients, cationic bovine serum albumin (CBSA)-injected rats and zymosan activation serum (ZAS)-treated podocytes. IMN patients show significantly decreased serum total protein and albumin levels, increased urine protein levels and intrarenal IgG4 and PLA2R protein expression in glomeruli compared with controls. IMN patients exhibited increased mRNA expression of intrarenal AHR and its target genes, including CYP1A1, CYP1A2, CYP1B1 and COX-2. This increase was accompanied by significantly upregulated protein expression of CD3, NF-ƙB p65 and COX-2 and significantly downregulated Nrf2 and HO-1 expression. Similarly, CBSA-induced rats showed severe proteinuria and activated intrarenal AHR signalling. This was accompanied by significantly upregulated protein expression of intrarenal p-IκBα, NF-κB p65 and its gene products, including COX-2, MCP-1, iNOS, 12-LOX, p47phox and p67phox, and significantly downregulated protein expression of Nrf2 and its gene products, including HO-1, catalase, GCLC, GCLM, MnSOD and NQO1. These results were further verified in ZAS-induced podocytes. Treatment with the AHR antagonist CH223191 and AHRsiRNA significantly preserved podocyte-specific protein expression and improved the NF-ƙB and Nrf2 pathways in ZAS-induced podocytes. In contrast, similar results were obtained in ZAS-induced podocytes treated with the NF-ƙB inhibitor BAY 11-7082 and NF-κBp65 siRNA. However, neither method had a significant effect on AHR signalling. Collectively, these results indicate that the NF-ƙB pathway is a downstream target of AHR signalling. Our findings suggest that blocking AHR signalling inhibits oxidative stress and inflammation, thereby improving proteinuria and renal injury.

Hexarelin alleviates apoptosis on ischemic acute kidney injury via MDM2/p53 pathway

INTRODUCTION

Hexarelin exhibits significant protection against organ injury in models of ischemia/reperfusion (I/R)-induced injury (IRI). Nevertheless, the impact of Hexarelin on acute kidney injury (AKI) and its underlying mechanism remains unclear. In this study, we investigated the therapeutic potential of Hexarelin in I/R-induced AKI and elucidated its molecular mechanisms.

METHODS

We assessed the protective effects of Hexarelin through both in vivo and in vitro experiments. In the I/R-induced AKI model, rats were pretreated with Hexarelin at 100 μg/kg/d for 7 days before being sacrificed 24 h post-IRI. Subsequently, kidney function, histology, and apoptosis were assessed. In vitro, hypoxia/reoxygenation (H/R)-induced HK-2 cell model was used to investigate the impact of Hexarelin on apoptosis in HK-2 cells. Then, we employed molecular docking using a pharmmapper server and autodock software to identify potential target proteins of Hexarelin.

RESULTS

In this study, rats subjected to I/R developed severe kidney injury characterized by tubular necrosis, tubular dilatation, increased serum creatinine levels, and cell apoptosis. However, pretreatment with Hexarelin exhibited a protective effect by mitigating post-ischemic kidney pathological changes, improving renal function, and inhibiting apoptosis. This was achieved through the downregulation of conventional apoptosis-related genes, such as Caspase-3, Bax and Bad, and the upregulation of the anti-apoptotic protein Bcl-2. Consistent with the in vivo results, Hexarelin also reduced cell apoptosis in post-H/R HK-2 cells. Furthermore, our analysis using GSEA confirmed the essential role of the apoptosis pathway in I/R-induced AKI. Molecular docking revealed a strong binding affinity between Hexarelin and MDM2, suggesting the potential mechanism of Hexarelin's anti-apoptosis effect at least partially through its interaction with MDM2, a well-known negative regulator of apoptosis-related protein that of p53. To validate these findings, we evaluated the relative expression of MDM2 and p53 in I/R-induced AKI with or without Hexarelin pre-administration and observed a significant suppression of MDM2 and p53 by Hexarelin in both in vivo and in vitro experiments.

CONCLUSION

Collectively, Hexarelin was identified as a promising medication in protecting apoptosis against I/R-induced AKI.

High glucose dialysate-induced peritoneal fibrosis: Pathophysiology, underlying mechanisms and potential therapeutic strategies

Peritoneal dialysis is an efficient renal replacement therapy for patients with end-stage kidney disease. However, continuous exposure of the peritoneal membrane to dialysate frequently leads to peritoneal fibrosis, which alters the function of the peritoneal membrane and results in withdrawal from peritoneal dialysis in patients. Among others, high glucose dialysate is considered as a predisposing factor for peritoneal fibrosis in patients on peritoneal dialysis. Glucose-induced inflammation, metabolism disturbance, activation of the renin-angiotensin-aldosterone system, angiogenesis and noninflammation-induced reactive oxygen species are implicated in the pathogenesis of high glucose dialysate-induced peritoneal fibrosis. Specifically, high glucose causes chronic inflammation and recurrent peritonitis, which could cause migration and polarization of inflammatory cells, as well as release of cytokines and fibrosis. High glucose also interferes with lipid metabolism and glycolysis by activating the sterol-regulatory element-binding protein-2/cleavage-activating protein pathway and increasing hypoxia inducible factor-1α expression, leading to angiogenesis and peritoneal fibrosis. Activation of the renin-angiotensin-aldosterone system and Ras-mitogen activated protein kinase signaling pathway is another contributing factor in high glucose dialysate-induced fibrosis. Ultimately, activation of the transforming growth factor-β1/Smad pathway is involved in mesothelial-mesenchymal transition or epithelial-mesenchymal transition, which leads to the development of fibrosis. Although possible intervention strategies for peritoneal dialysate-induced fibrosis by targeting the transforming growth factor-β1/Smad pathway have occasionally been proposed, lack of laboratory evidence renders clinical decision-making difficult. We therefore aim to revisit the upstream pathways of transforming growth factor-beta1/Smad and propose potential therapeutic targets for high glucose-induced peritoneal fibrosis.

Torpor-responsive microRNAs in the heart of the Monito del monte, Dromiciops gliroides

The marsupial Monito del monte (Dromiciops gliroides) utilizes both daily and seasonal bouts of torpor to preserve energy and prolong survival during periods of cold and unpredictable food availability. Torpor involves changes in cellular metabolism, including specific changes to gene expression that is coordinated in part, by the posttranscriptional gene silencing activity of microRNAs (miRNA). Previously, differential miRNA expression has been identified in D. gliroides liver and skeletal muscle; however, miRNAs in the heart of Monito del monte remained unstudied. In this study, the expression of 82 miRNAs was assessed in the hearts of active and torpid D. gliroides, finding that 14 were significantly differentially expressed during torpor. These 14 miRNAs were then used in bioinformatic analyses to identify Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways that were predicted to be most affected by these differentially expressed miRNAs. Overexpressed miRNAs were predicted to primarily regulate glycosaminoglycan biosynthesis, along with various signaling pathways such as Phosphoinositide-3-kinase/protein kinase B and transforming growth factor-β. Similarly, signaling pathways including phosphatidylinositol and Hippo were predicted to be regulated by the underexpression of miRNAs during torpor. Together, these results suggest potential molecular adaptations that protect against irreversible tissue damage and enable continued cardiac and vascular function despite hypothermia and limited organ perfusion during torpor.

Moshen granule ameliorates membranous nephropathy by regulating NF-ƙB/Nrf2 pathways via aryl hydrocarbon receptor signalling

Considerable achievements were realized in illuminating underlying pathological mechanisms of patients with idiopathic membranous nephropathy (IMN). Although IMN patients are well diagnosed before they reach renal failure, no currently available drug intervention is effective in halting IMN progression. In this study, we assess Moshen granule (MSG) effect on IMN patients and cationic bovine serum albumin (CBSA)-induced rats. Increasing studies has indicated that activation of aryl hydrocarbon receptor (AHR) was related to oxidative stress and inflammation. We further determine MSG effect on AHR, nuclear factor ƙB (NF-ƙB) and nuclear factor erythroid 2-related factor 2 (Nrf2) in the CBSA-induced rats. MSG markedly reduces proteinuria and improves kidney function in both IMN patients and rats induced by CBSA. MSG markedly inhibits increased mRNA expressions of intrarenal AHR and its four downstream target genes including CYP1A1, CYP1A2, CYP1B1 and COX-2 compared with untreated CBSA-induced rats. This is accompanied by markedly downregulated protein expressions of p-IƙBα and NF-ƙB p65 and its downstream gene products including MCP-1, COX-2, 12-LOX, iNOS, p47phox and p67phox, while markedly preserves protein expressions of Nrf2 and its downstream gene products including catalase, HO-1, GCLM, GCLC, MnSOD and NQO1 in the kidney tissues. These data suggests MSG blunts podocyte damage through inhibiting activation of NF-ƙB/Nrf2 pathway via AHR signaling. This finding may provide a promising therapy for treatment of IMN through oxidative stress and inflammation.