Zhiming Hao

Interstitial lung disease (ILD) is a group of heterogeneous diffuse pulmonary diseases that share similar pathological manifestations, including lung injury, inflammation and fibrosis, despite their distinct etiologies and comorbidities. Most of ILDs ultimately progress to pulmonary fibrosis (PF) with irreversible damage to lung tissue. Recent studies have recognized that an imbalance between pro- and anti-fibrotic signals plays a pivotal role in the occurrence and persistence of tissue fibrosis, including PF. TGF-βs present the most potent pro-fibrotic signaling, while bone morphogenetic proteins (BMPs)-mediated signaling, especially BMP-7, exerts a major anti-fibrotic action by opposing TGF-β signaling in fibrosis of liver, kidneys and heart. Although BMP-4 has been reported to be involved in PF, its specific regulatory mechanisms have not been fully explored. In this study, we determined the function of BMP-4 in lung injury, inflammation and fibrosis and explored the underlying mechanism. The expression of BMP-4 was decreased in human and mouse (bleomycin-induced) fibrotic lung tissues. Moreover, BMP-4 receptors and downstream signaling molecules were downregulated in mouse fibrotic lung tissues. Oppositely, expression of TGF-β1, -β2, -β3, TGF-β receptors and their signaling molecules was elevated in mouse fibrotic lung tissues. Adenovirus-mediated BMP-4 expression attenuated bleomycin-induced lung oxidative injury, inflammation and fibrosis in mice. Recombinant BMP-4 inhibited TGF-β1-induced macrophage activation, fibroblast differentiation into myofibroblasts, epithelial-to-mesenchymal transition and endothelial-to-mesenchymal transition in vitro. Furthermore, BMP-4 mitigated the increases in TGF-β-associated signaling molecule expression while reversing the decreases of BMP-associated signaling molecules in fibrotic mouse lungs and TGF-β1-treated cells. Taken together, our study provides substantial evidence for the protective function of BMP-4 in lung oxidative injury, inflammation and fibrosis by restoring the imbalance between BMP and TGF-β signaling.

Extracellular high mobility group box 1 (HMGB1) serves as a key damage-associated molecular pattern that drives the pathological process of inflammatory liver injury; however, its role in liver fibrosis and the underlying mechanisms need to be elucidated. To investigate the proinflammatory and profibrotic roles of extracellular HMGB1, we used an adenovirus-mediated system to measure HMGB1 secretion in mice. We subsequently constructed two recombinant proteins, PfTrx-HMGB1 ¹⁷ (95 − 111) and HBcΔ-HMGB1 ³⁴ (150 − 183), targeting the interactions of HMGB1 with its receptors, namely, toll-like receptor 4 (TLR4) and receptor for advanced glycation end products (RAGE), respectively. Mice were immunized with the two recombinant proteins to assess neutralizing antibody induction and the protective effects of the HMGB1 vaccines against carbon tetrachloride (CCl ₄ )-induced liver fibrosis. Our results revealed the nucleocytoplasmic translocation of HMGB1 in the livers of both humans and mice with fibrosis. Extracellular HMGB1 induced liver inflammation and fibrogenesis in mice. Immunization with the two HMGB1 vaccines resulted in the production of high levels of anti-HMGB1 neutralizing antibodies, which inhibited the activation of hepatic stellate cells (LX-2) and the production of proinflammatory and profibrotic factors in RAW 264.7 cells. Furthermore, vaccination with these compounds significantly protected against CCl ₄ -induced liver injury, inflammation, and fibrosis in mice. These findings demonstrate that extracellular HMGB1, by binding to TLR4 or RAGE, is pivotal in driving liver inflammation and fibrosis. Vaccination against HMGB1 through disruption of interaction with TLR4 or RAGE represents a promising therapeutic strategy for hepatic fibrosis.

Background: T helper 17 (Th17) cells participate in all pathological stages of systemic sclerosis (SSc). Molecular markers associated with Th17 cells hold promise as therapeutic targets for SSc. This study aims to screen and validate key genes related to Th17 cells that have diagnostic and predictive value in SSc and to identify potential therapeutic targets for SSc. Methods: Candidate genes were identified by intersecting Th17 cell-dysregulated genes (TCDRGs) from single-cell RNA sequencing data (GSE292979) with bulk RNA sequencing data (GSE95065). Machine learning algorithms, receiver operating characteristic (ROC) curve analysis, and expression level validation were employed to further identify key Th17-related genes. Subsequently, the diagnostic and predictive capabilities of these Th17-related genes were validated using a nomogram model. Then, gene set enrichment analysis (GSEA), immune infiltration analysis, drug prediction, and molecular docking were conducted on the key genes. Finally, the expression of genes was confirmed in bleomycin (BLM)-induced SSc mice. Results: We identified 48 candidate genes from 472 TCDRGs and 1653 bulk DEGs. Using the Boruta feature selection algorithm and random forest (RF) model, two genes related to Th17 cells, PGAP1 and TMBIM1, were identified. PGAP1 and TMBIM1 exhibited exceptional discriminative efficiency with an AUC of 0.9852 in the nomogram model. Moreover, GSEA analysis revealed that both genes were co-enriched in pathways such as oxidative phosphorylation and the proteasome. Immune infiltration analysis indicated that PGAP1 and TMBIM1 were closely associated with five types of immune cells, exhibiting opposing correlation trends, such as with M1-type macrophages. Drug prediction analysis identified 45 potential drugs targeting PGAP1 and 36 targeting TMBIM1. Notably, Bafilomycin A1 was associated with PGAP1, while Ciglitazone was associated with TMBIM1, and both displayed stable binding conformations. Finally, in a BLM-induced mouse model, quantitative real-time PCR analysis and immunohistochemical experiments revealed upregulation of TMBIM1, whereas PGAP1 expression was downregulated in fibrotic skin and lung tissues. These results suggest the relevance of PGAP1 and TMBIM1 in fibrotic processes. However, further studies using human SSc samples are warranted to confirm their diagnostic and therapeutic potential. Conclusion: PGAP1 and TMBIM1 have been identified as key molecules associated with Th17 cells. They exhibit significant diagnostic and predictive value in SSc and show promise as therapeutic targets for SSc. Key Points • SSc skin tissues exhibit significant changes in the composition of immune and non-immune cells. • PGAP1 and TMBIM1 have been identified as key molecules in SSc that are associated with Th17 cells, showing remarkable diagnostic accuracy. • PGAP1 and TMBIM1 exhibit a negative correlation in their expression patterns in SSc.

To assess the association between clinical indicators (primarily Body Mass Index, BMI) and disease activity in systemic lupus erythematosus (SLE) populatio

Background: High mobility group box 1 (HMGB1) plays an essential role in various pathological conditions, including inflammation, fibrosis, autoimmune diseases, and carcinogenesis. The quantification of HMGB1 in body fluids holds promise for clinical applications. Objectives: This study aimed to isolate high-affinity single-stranded DNA (ssDNA) aptamers that target HMGB1. Methods: In this study, ssDNA aptamers were selected using Systematic Evolution of Ligands by Exponential Enrichment (SELEX). The affinity and specificity of the aptamers were evaluated through South-Western blot analysis, enzyme-linked aptamer sorbent assay (ELASA), and aptamer-based histochemistry staining. The impact of the aptamers on the biological activity of HMGB1 was tested in the human acute monocytic leukemia cell line, THP-1. Results: An aptamer (H-ap25, dissociation constant = 8.20 ± 0.53 nmol/L) with high affinity for the HMGB1 B box was generated. Further experiments verified that H-ap25 can be used to detect HMGB1 in South-Western blot analysis, ELASA, and aptamer-based histochemistry staining. Moreover, H-ap25 significantly augmented HMGB1-induced expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, Toll-like receptor 9 (TLR9), and activation of NF-κB in THP-1 cells. Conclusions: Our results demonstrated that H-ap25 can be used both as an enhancer of HMGB1 and as a probe in research.

Hepatocarcinoma‐intestine‐pancreas/pancreatitis‐associated protein (HIP/PAP), a C‐type lectin, exerts anti‐oxidative, anti‐inflammatory, bactericidal, anti‐apoptotic, and mitogenic functions in several cell types and tissues. In this study, we explored the role of HIP/PAP in pulmonary fibrosis (PF). Expression of HIP/PAP and its murine counterpart, Reg3B, was markedly increased in fibrotic human and mouse lung tissues. Adenovirus‐mediated HIP/PAP expression markedly alleviated bleomycin (BLM)‐induced lung injury, inflammation, and fibrosis in mice. Adenovirus‐mediated HIP/PAP expression alleviated oxidative injury and lessened the decrease in pulmonary superoxide dismutase (SOD) activity in BLM‐treated mice, increased pulmonary SOD expression in normal mice, and HIP/PAP upregulated SOD expression in cultured human alveolar epithelial cells (A549) and human lung fibroblasts (HLF‐1). Moreover, in vitro experiments showed that HIP/PAP suppressed the growth of HLF‐1 and ameliorated the H₂O₂‐induced apoptosis of human alveolar epithelial cells (A549 and HPAEpiC) and human pulmonary microvascular endothelial cells (HPMVEC). In HLF‐1, A549, HPAEpiC, and HPMVEC cells, HIP/PAP did not affect the basal levels, but alleviated the TGF‐β1‐induced down‐regulation of the epithelial/endothelial markers E‐cadherin and vE‐cadherin and the over‐expression of mesenchymal markers, such as α‐SMA and vimentin. In conclusion, HIP/PAP was found to serve as a potent protective factor in lung injury, inflammation, and fibrosis by attenuating oxidative injury, promoting the regeneration of alveolar epithelial cells, and antagonizing the pro‐fibrotic actions of the TGF‐β1/Smad signaling pathway.

Aberrant expression of microRNA‐876‐5p (miR‐876‐5p) is implicated in the progression of multiple human cancers. However, the potential role of miR‐876‐5p in colorectal cancer remains poorly understood. The purpose of the current study was to investigate the potential role of miR‐876‐5p in colorectal cancer. miR‐876‐5p expression was significantly downregulated in colorectal cancer tissues and cell lines compared with normal controls. Gain‐of‐function assays revealed that miR‐876‐5p overexpression effectively repressed the malignant behaviours of colorectal cancer cells, including cell proliferation, colony formation, and invasion. Bioinformatics analysis predicted that RAS protein activator like 2 (RASAL2), a potential oncogene for colorectal cancer, is a putative miR‐876‐5p target gene. A luciferase reporter assay confirmed that miR‐876‐5p directly binds to the 3′‐untranslated region (UTR) of RASAL2. Furthermore, both RASAL2 messenger RNA (mRNA) and protein expression were negatively modulated by miR‐876‐5p in colorectal cancer cells. Notably, there was an inverse correlation between miR‐876‐5p and RASAL2 expression in colorectal cancer tissue specimens. Moreover, miR‐876‐5p was involved in regulating the activation of Yes‐associated protein (YAP) signalling through inhibiting RASAL2. However, the miR‐876‐5p‐mediated antitumour effect on colorectal cancer cells was partially reversed by restoring RASAL2 expression. Notably, miR‐876‐5p upregulation impeded the tumour growth of colorectal cancer cells in vivo in nude mice. Overall, these results demonstrated that miR‐876‐5p exerts an antitumour function in colorectal cancer by targeting RASAL2 to suppress YAP signalling activation. These findings highlight the importance of the miR‐876‐5p/RASAL2/YAP axis in colorectal cancer progression and suggest that miR‐876‐5p is a potential therapeutic target for treating colorectal cancer.