Transforming growth factor-β1 suppress pentraxin-3 in human orbital fibroblasts

Research Progress of Chinese Medicine in the Regulation of Liver Fibrosis-Related Signaling Pathways

Liver fibrosis is a common complication of chronic liver disease, significantly affecting patients' quality of life and potentially leading to cirrhosis and hepatocellular carcinoma. Despite advancements in modern medicine, the treatment of liver fibrosis remains limited and challenging. Thus, identifying new therapeutic strategies is of great clinical importance. Signaling pathways related to liver fibrosis play a crucial regulatory role in immune response and inflammation. Aberrant activation of specific pathways, such as the NF-[Formula: see text]B signaling pathway, results in the overexpression of genes associated with liver inflammation and fibrosis, thereby promoting the progression of liver fibrosis. Chinese medicine offers unique potential advantages as a therapeutic approach. Recent studies have increasingly demonstrated that certain Chinese medicines can effectively treat liver fibrosis by regulating relevant signaling pathways. The active ingredients in these medicines can inhibit hepatic inflammatory responses and fibrotic processes by interfering with these pathways, thus reducing the severity of liver fibrosis. This paper aims to investigate the mechanisms of Chinese medicine in treating liver fibrosis and its modulation of related signaling pathways. Additionally, it discusses the prospects of the clinical application of these treatments and provides valuable references for further research and clinical practice.

Strategy for treating MAFLD: Electroacupuncture alleviates hepatic steatosis and fibrosis by enhancing AMPK mediated glycolipid metabolism and autophagy in T2DM rats

BACKGROUND

Recent studies have highlighted type 2 diabetes (T2DM) as a significant risk factor for the development of metabolic dysfunction-associated fatty liver disease (MAFLD). This investigation aimed to assess electroacupuncture's (EA) impact on liver morphology and function in T2DM rats, furnishing experimental substantiation for its potential to stall MAFLD progression in T2DM.

METHODS

T2DM rats were induced by a high-fat diet and a single intraperitoneal injection of streptozotocin, and then randomly assigned to five groups: the T2DM group, the electroacupuncture group, the metformin group, combination group of electroacupuncture and metformin, combination group of electroacupuncture and Compound C. The control group received a standard diet alongside intraperitoneal citric acid - sodium citrate solution injections. After a 6-week intervention, the effects of each group on fasting blood glucose, lipids, liver function, morphology, lipid droplet infiltration, and fibrosis were evaluated. Techniques including Western blotting, qPCR, immunohistochemistry, and immunofluorescence were employed to gauge the expression of key molecules in AMPK-associated glycolipid metabolism, insulin signaling, autophagy, and fibrosis pathways. Additionally, transmission electron microscopy facilitated the observation of liver autophagy, lipid droplets, and fibrosis.

RESULTS

Our studies indicated that hyperglycemia, hyperlipidemia and IR promoted lipid accumulation, pathological and functional damage, and resulting in hepatic steatosis and fibrosis. Meanwhile, EA enhanced the activation of AMPK, which in turn improved glycolipid metabolism and autophagy through promoting the expression of PPARα/CPT1A and AMPK/mTOR pathway, inhibiting the expression of SREBP1c, PGC-1α/PCK2 and TGFβ1/Smad2/3 signaling pathway, ultimately exerting its effect on ameliorating hepatic steatosis and fibrosis in T2DM rats. The above effects of EA were consistent with metformin. The combination of EA and metformin had significant advantages in increasing hepatic AMPK expression, improving liver morphology, lipid droplet infiltration, fibrosis, and reducing serum ALT levels. In addition, the ameliorating effects of EA on the progression of MAFLD in T2DM rats were partly disrupted by Compound C, an inhibitor of AMPK.

CONCLUSIONS

EA upregulated hepatic AMPK expression, curtailing gluconeogenesis and lipogenesis while boosting fatty acid oxidation and autophagy levels. Consequently, it mitigated blood glucose, lipids, and insulin resistance in T2DM rats, thus impeding liver steatosis and fibrosis progression and retarding MAFLD advancement.

Pulmonary fibroblast-specific delivery of siRNA exploiting exosomes-based nanoscaffolds for IPF treatment

Idiopathic pulmonary fibrosis (IPF) is a progressive pulmonary disease that leads to interstitial inflammation, lung damage, and eventually life-threatening complications. Among various pathologic factors, Smad4 is a pivotal molecule involved in the progression and exacerbation of IPF. It mediates nuclear transfer of Smad2/Smad3 complexes and initiates the transcription of fibrosis-promoting genes. Thus, the inhibition of Smad4 expression in pulmonary fibroblasts by small interfering RNAs (siRNAs) might be a promising therapeutic strategy for IPF. Herein, we engineered exosome membranes (EM) by cationic lipid (i.e., DOTAP) to load siRNAs against Smad4 (DOTAP/siSmad4@EM), and investigated their specific delivery to pulmonary fibroblasts for treating IPF in a mouse model via pulmonary administration. As reference nanoscaffolds, undecorated DOTAP/siSmad4 complexes (lipoplexes, consisting of cationic lipid DOTAP and siRNAs) and siSmad4-loaded lipid nanoparticles (DOTAP/siSmad4@lipo, consisting of lipoplexes fused with DPPC-Chol liposomes) were also prepared. The results showed that DOTAP/siSmad4@EM exhibited a higher cellular uptake and gene silencing efficacies in mouse pulmonary fibroblasts (viz., MLg2908) as compared to the two reference nanoscaffolds. Furthermore, the outcomes of the in vivo experiments illustrated that DOTAP/siSmad4@EM could significantly down-regulate the Smad4 expression with augmented anti-fibrosis efficiency. Additionally, the DOTAP/siSmad4@EM conferred excellent biocompatibility with low cytokine levels in bronchoalveolar lavage fluid and proinflammatory responses in the pulmonary area. Taken together, the outcomes of our investigation imply that specific inhibition of Smad4 expression in pulmonary fibroblasts by pulmonary administrated DOTAP/siSmad4@EM is a promising therapeutic strategy for IPF, which could safely and effectively deliver siRNA drugs to the targeted site of action.

Inflammation in diabetes complications: molecular mechanisms and therapeutic interventions

At present, diabetes mellitus (DM) has been one of the most endangering healthy diseases. Current therapies contain controlling high blood sugar, reducing risk factors like obesity, hypertension, and so on; however, DM patients inevitably and eventually progress into different types of diabetes complications, resulting in poor quality of life. Unfortunately, the clear etiology and pathogenesis of diabetes complications have not been elucidated owing to intricate whole-body systems. The immune system was responsible to regulate homeostasis by triggering or resolving inflammatory response, indicating it may be necessary to diabetes complications. In fact, previous studies have been shown inflammation plays multifunctional roles in the pathogenesis of diabetes complications and is attracting attention to be the meaningful therapeutic strategy. To this end, this review systematically concluded the current studies over the relationships of susceptible diabetes complications (e.g., diabetic cardiomyopathy, diabetic retinopathy, diabetic peripheral neuropathy, and diabetic nephropathy) and inflammation, ranging from immune cell response, cytokines interaction to pathomechanism of organ injury. Besides, we also summarized various therapeutic strategies to improve diabetes complications by target inflammation from special remedies to conventional lifestyle changes. This review will offer a panoramic insight into the mechanisms of diabetes complications from an inflammatory perspective and also discuss contemporary clinical interventions.

Identification and validation of ferroptosis-related genes and immune cell infiltration in thyroid associated ophthalmopathy

Thyroid associated ophthalmopathy (TAO) is an orbital autoimmune inflammatory disease that is commonly associated with thyroid dysfunction. Although the etiology of TAO is unclear, ROS accumulation and oxidative stress have been closely linked to the pathogenesis of TAO. Ferroptosis is an iron-dependent programmed cell death characterized by intracellular labile iron levels, excessive accumulation of reactive oxygen species (ROS) and lipid peroxidation. Currently, there are few reports regarding the role of ferroptosis in TAO. This article aimed to identify ferroptosis-related genes (FRGs) with diagnostic and therapeutic potential in TAO and explore their relationship with immune cells and lncRNAs. GSE58331 was downloaded from Gene Expression Omnibus (GEO) database. A total of 162 DEGs were identified between 27 TAO samples and 22 health samples from GSE58331, among which six FRGs (CYBB, CTSB, SLC38A1, TLR4, PEX3, and ABCC1) were obtained. The AUC of SLC38A1, TLR4, PEX3 in lacrimal gland tissues was greater than 80 which suggested high diagnostic value in TAO. The result of immune cell infiltrate analysis indicated increased infiltration of monocytes (p < 0.001), macrophages M0(p = 0.039), mast cells activated (p = 0.008), and neutrophils (p = 0.045) in orbital tissues from TAO patients. Meanwhile, mast cells resting (p = 0.043) and macrophages M2 (p = 0.02) showed reduced infiltration in TAO samples. There were no gender differences in immune cell infiltration in the TAO patients. Two differentially expressed lncRNAs, LINC01140 and ZFHX4-AS1, in TAO groups were identified as ferroptosis-related lncRNAs. CYBB-LINC01140-TLR4, CYBB- LINC01140- SLC38A1, TLR4- LINC01140- SLC38A1, and CTSB- ZFHX4-AS1- CYBB may be potential RNA regulatory pathways in TAO. Targeted drugs and transcription factors for differential expressed FRGs were also screened out in our study. In vitro, experiments revealed that CTSB, PEX3, ABCC1 and ZFHX4-AS1(lncRNA) were differentially expressed in orbital fibroblasts (OFs) between TAO groups and healthy controls at the transcriptional level.

The crossroad between autoimmune disorder, tissue remodeling and cancer of the thyroid: The long pentraxin 3 (PTX3)

Thyroid is at the crossroads of immune dysregulation, tissue remodeling and oncogenesis. Autoimmune disorders, nodular disease and cancer of the thyroid affect a large amount of general population, mainly women. We wondered if there could be a common factor behind three processes (immune dysregulation, tissue remodeling and oncogenesis) that frequently affect, sometimes coexisting, the thyroid gland. The long pentraxin 3 (PTX3) is an essential component of the humoral arm of the innate immune system acting as soluble pattern recognition molecule. The protein is found expressed in a variety of cell types during tissue injury and stress. In addition, PTX3 is produced by neutrophils during maturation in the bone-marrow and is stored in lactoferrin-granules. PTX3 is a regulator of the complement cascade and orchestrates tissue remodeling and repair. Preclinical data and studies in human tumors indicate that PTX3 can act both as an extrinsic oncosuppressor by modulating complement-dependent tumor-promoting inflammation, or as a tumor-promoter molecule, regulating cell invasion and proliferation and epithelial to mesenchymal transition, thus suggesting that this molecule may have different functions on carcinogenesis. The involvement of PTX3 in the regulation of immune responses, tissue remodeling and oncosuppressive processes led us to explore its potential role in the development of thyroid disorders. In this review, we aimed to highlight what is known, at the state of the art, regarding the connection between the long pentraxin 3 and the main thyroid diseases i.e., nodular thyroid disease, thyroid cancer and autoimmune thyroid disorders.

Potential Therapeutic Activity of Berberine in Thyroid-Associated Ophthalmopathy: Inhibitory Effects on Tissue Remodeling in Orbital Fibroblasts

Purpose

Berberine (BBR), an alkaloid produced by a traditional Chinese plant, was recently attributed multiple effects on lipometabolism, inflammation, and fibrosis. Thyroid-associated ophthalmopathy (TAO) is highly associated with these pathologic changes. Thus, we aimed to examine the potential therapeutic effect of BBR in an in vitro model of TAO.

Methods

Orbital fibroblasts (OFs) obtained from control donors (n = 6) or patients with TAO (n = 6) were cultured. The CCK-8 assay was conducted for assessing the optimal concentration range. Oil Red O staining, Western blotting, and quantitative RT-PCR (qRT-PCR) were conducted to assess adipogenesis in OFs. RNA sequencing (RNA-seq) was used to screen the key pathways of the antiadipogenic effect mediated by BBR. Along with incremental concentrations of BBR, IL-1β–induced expression of proinflammatory molecules was determined by ELISA and qRT-PCR. In addition, TGF-β–induced hyaluronan (HA) production and fibrosis were evaluated by ELISA, qRT-PCR, and Western blotting.

Results

TAO-OFs, but not control fibroblasts (CON-OFs), were readily differentiated into adipocytes with the commercial medium. Intracellular lipid accumulation was dose-dependently decreased by BBR, and adipogenic markers were also downregulated. Moreover, the PPARγ and AMPK pathways were screened out by RNA-seq and their downstream effectors were suppressed by BBR. Besides, BBR attenuated IL-1β–induced expression of proinflammatory molecules in both TAO-OFs and CON-OFs by blocking nuclear factor–κB signaling. BBR's inhibitory effect on TGF-β–mediated tissue remodeling was also confirmed in OFs.

Conclusions

These findings demonstrate BBR has outstanding capabilities of controlling adipogenesis, inflammation, HA production, and fibrosis in OFs, highlighting its potential therapeutic role in TAO management.

TGF-β induces GBM mesenchymal transition through upregulation of CLDN4 and nuclear translocation to activate TNF-α/NF-κB signal pathway

Glioblastoma (GBM) is the most common and aggressive primary malignant brain tumor. The unregulated expression of Claudin-4 (CLDN4) plays an important role in tumor progression. However, the biological role of CLDN4 in GBM is still unknown. This study aimed to determine whether CLDN4 mediates glioma malignant progression, if so, it would further explore the molecular mechanisms of carcinogenesis. Our results revealed that CLDN4 was significantly upregulated in glioma specimens and cells. The inhibition of CLND4 expression could inhibit mesenchymal transformation, cell invasion, cell migration and tumor growth in vitro and in vivo. Moreover, combined with in vitro analysis, we found that CLDN4 can modulate tumor necrosis factor-α (TNF-α) signal pathway. Meanwhile, we also validated that the transforming growth factor-β (TGF-β) signal pathway can upregulate the expression of CLDN4, and promote the invasion ability of GBM cells. Conversely, TGF-β signal pathway inhibitor ITD-1 can downregulate the expression of CLDN4, and inhibit the invasion ability of GBM cells. Furthermore, we found that TGF-β can promote the nuclear translocation of CLDN4. In summary, our findings indicated that the TGF-β/CLDN4/TNF-α/NF-κB signal axis plays a key role in the biological progression of glioma. Disrupting the function of this signal axis may represent a new treatment strategy for patients with GBM.

Quantitative T1 mapping MRI for the assessment of extraocular muscle fibrosis in thyroid-associated ophthalmopathy

PURPOSE

We aimed to investigate the performance of T1 mapping and its histological correlation with extraocular muscle fibrosis in thyroid-associated ophthalmopathy (TAO).

METHODS

We prospectively recruited 12 cases of active TAO, 12 cases of inactive TAO, and 15 cases of control subjects. All participants underwent magnetic resonance imaging (MRI) scan with pre-/postcontrast T1 mapping and short-time inversion-recovery (STIR) sequence. The images were analyzed to obtain precontrast T1, extracellular-volume (ECV) fraction on T1 mapping, and signal-intensity ratio (SIR) on STIR for each rectus. Muscle biopsy was performed at lateral rectus to quantify-collagen volume fraction, glycosaminoglycan (GAG)-volume fraction, and extracellular space component. The relationship between MRI and histopathology was examined with Pearson correlation coefficient.

RESULTS

The active TAO group was characterized with GAG accumulation, while the inactive TAO group presented with substantial fibrosis. The MRI parameters achieved acceptable interobserver and intraobserver agreement. The precontrast T1 and ECV remarkably increased in the TAO groups than the control group, and ECV positively correlated with collagen-volume fraction (r = 0.913) and extracellular-space component (r = 0.886) in the inactive TAO group. The SIR statistically increased in the active TAO group, and SIR positively correlated with GAG-volume fraction in all three groups. The performance of ECV (cutoff > 48.1%) to screen out extraocular muscle fibrosis in inactive TAO was 60.9% sensitivity and 93.3% specificity.

CONCLUSIONS

The ECV parameter on T1 mapping MRI is a reliable tool to quantify extraocular muscle fibrosis, providing insights into noninvasive evaluation of pathological changes in TAO orbit.

TRIAL REGISTRATION NUMBER

ChiCTR2000040394; Date of registration: 28 November 2020.