microRNA-21, via the HIF-1α/VEGF signaling pathway, is involved in arsenite-induced hepatic fibrosis through aberrant cross-talk of hepatocytes and hepatic stellate cells

A comprehensive review of miR-21 in liver disease: Big impact of little things

microRNAs (miRNAs), a class of non-coding RNA with 20-24 nucleotides, are defined as the powerful regulators for gene expression. miR-21 is a multifunctional miRNA enriched in the circulatory system and multiple organs, which not only serves as a non-invasive biomarker in disease diagnosis, but also participates in many cellular activities. In various chronic liver diseases, the increase of miR-21 affects glycolipid metabolism, viral infection, inflammatory and immune cell activation, hepatic stellate cells activation and tissue fibrosis, and autophagy. Moreover, miR-21 is also a liaison in the deterioration of chronic liver disease to hepatocellular carcinoma (HCC), and it impacts on cell proliferation, apoptosis, migration, invasion, angiogenesis, immune escape, and epithelial-mesenchymal transformation by regulating target genes expression in different signaling pathways. In current research on miRNA therapy, some natural products can exert the hepatoprotective effects depending on the inhibition of miR-21 expression. In addition, miR-21-based therapeutic also play a role in regulating intracellular miR-21 levels and enhancing the efficacy of chemotherapy drugs. Herein, we systemically summarized the recent progress of miR-21 on biosynthesis, biomarker function, molecular mechanism and miRNA therapy in chronic liver disease and HCC, and looked forward to outputting some information to enable it from bench to bedside.

The role of exosome-shuttled miRNAs in heavy metal-induced peripheral tissues and neuroinflammation in Alzheimer's disease

Heavy metal-induced neuroinflammation is a significant pathophysiologic mechanism in Alzheimer's disease (AD). Microglia-mediated neuroinflammation plays a crucial role in the pathogenesis of AD. Multiple miRNAs are differentially expressed in peripheral tissues after heavy metal exposure, and increasing evidence suggests that they are involved in AD progression by regulating microglial homeostasis. Exosomes, which are capable of loading miRNAs and crossing the bloodbrain barrier, serve as mediators of communication between peripheral tissues and the brain. In this review, we summarize the current evidence on the link between miRNAs in peripheral tissues and neuroinflammation in AD after heavy metal exposure and propose a role for miRNAs in the microglial neurodegenerative phenotype (MGnD) of AD. This study will help to elucidate the link between peripheral tissue damage and MGnD-mediated neuroinflammation in AD after heavy metal exposure. Additionally, we summarize the regulatory effects of natural compounds on peripheral tissue-derived miRNAs, which could be potential therapeutic targets for natural compounds to regulate peripheral tissue-derived exosomal miRNAs to ameliorate heavy metal-induced MGnD-mediated neuroinflammation in patients with AD after heavy metal exposure.

The hippo-YAP1/HIF-1α pathway mediates arsenic-induced renal fibrosis

Epidemiological evidence reveals that arsenic increases the risk of chronic kidney disease (CKD) in humans, but its mechanism of action has so far been unclear. Fibrosis is the manifestation of end-stage renal disease. Hypoxia is recognized as a vital event accompanying the progression of renal fibrosis. KM mice were exposed to 0, 20, 40, and 80 mg/L NaAsO2 for 12 weeks. HK-2 cells were treated with 1 μM NaAsO2 for 4 weeks. The results showed that arsenic increased the expression of hypoxia-inducible factor 1α (HIF-1α) (P < 0.05), which is involved in inorganic arsenic-induced renal fibrosis. The Hippo signaling pathway is the upstream signal of HIF-1α and the kinase cascade of Large tumor suppressor kinase 1 (LATS1) and Yes-associated protein 1 (YAP1) is the heart of the Hippo pathway. Our results showed that protein expressions of LATS1 and phosphorylated YAP1 were decreased, and dephosphorylated YAP1 expression increased in arsenic-treated mouse kidneys and human HK-2 cells (P < 0.05). Our research manifested that arsenic treatment suppressed the Hippo signaling and induced high expression of YAP1 into the nucleus. We also found that YAP1 was involved in arsenic-induced renal fibrosis by forming a complex with HIF-1α and maintaining HIF-1α stability. Our findings indicate that YAP1 is a potential target for molecular-based therapy for arsenic-mediated renal fibrosis.

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

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

Tumor-associated macrophage-derived exosomal miR21-5p promotes tumor angiogenesis by regulating YAP1/HIF-1α axis in head and neck squamous cell carcinoma

Extracellular vesicles (EVs) have recently received increasing attention as essential mediators of communication between tumor cells and their microenvironments. Tumor-associated macrophages (TAMs) play a proangiogenic role in various tumors, especially head and neck squamous cell carcinoma (HNSCC), and angiogenesis is closely related to tumor growth and metastasis. This research focused on exploring the mechanisms by which EVs derived from TAMs modulate tumor angiogenesis in HNSCC. Our results indicated that TAMs infiltration correlated positively with microvascular density in HNSCC. Then we collected and identified EVs from TAMs. In the microfluidic chip, TAMs derived EVs significantly enhanced the angiogenic potential of pHUVECs and successfully induced the formation of perfusable blood vessels. qPCR and immunofluorescence analyses revealed that EVs from TAMs transferred miR-21-5p to endothelial cells (ECs). And targeting miR-21-5p of TAMs could effectively inhibit TAM-EVs induced angiogenesis. Western blot and tube formation assays showed that miR-21-5p from TAM-EVs downregulated LATS1 and VHL levels but upregulated YAP1 and HIF-1α levels, and the inhibitors of YAP1 and HIF-1α could both reduce the miR-21-5p enhanced angiogenesis in HUVECs. The in vivo experiments further proved that miR-21-5p carried by TAM-EVs promoted the process of tumor angiogenesis via YAP1/HIF-1α axis in HNSCC. Conclusively, TAM-derived EVs transferred miR-21-5p to ECs to target the mRNA of LATS1 and VHL, which inhibited YAP1 phosphorylation and subsequently enhanced YAP1-mediated HIF-1α transcription and reduced VHL-mediated HIF-1α ubiquitination, contributing to angiogenesis in HNSCC. These findings present a novel regulatory mechanism of tumor angiogenesis, and miR-21-5p/YAP1/HIF-1α might be a potential therapeutic target for HNSCC.

Impacts of non-coding RNAs in the pathogenesis of varicocele

Two classes of non-coding RNAs, namely lncRNAs and miRNAs have been reported to be involved in the pathogenesis of varicocele. MIR210HG, MLLT4-AS1, gadd7, and SLC7A11-AS1 are among lncRNAs whose expression has been changed in patients with varicocele in association with the sperm quality. Animal studies have also suggested contribution of NONRATG001060, NONRATG002949, NONRATG013271, NONRATG027523 and NONRATG023747 lncRNAs in this pathology. Meanwhile, expression of some miRNAs, such as miR-210-3p, miR-21, miR-34a, miR-122a, miR-181a, miR-34c and miR-192a has been altered in this condition. Some of these transcripts have the potential to predict the sperm quality. We summarize the impacts of lncRNAs and miRNAs in the pathogenesis of varicocele.

Mechanisms and targeted reversion/prevention of hepatic fibrosis caused by the non-hereditary toxicity of benzo(a)pyrene

The effect of long term exposure to low concentrations of environmental pollutants on hepatic disorders is a major public health concern worldwide. Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants. In recent years, an increasing number of studies have focused on the deleterious effects of low concentrations of PAHs in the initiation or exacerbation of the progression of chronic liver disease. However, the underlying molecular mechanisms and effective intervention methods remain unclear. Here, we found that in hepatocytes, a low concentration of benzo(a)pyrene (B[a]P, an indicator of PAHs) chronic exposure continuously activated 14-3-3η via an epigenetic accumulation of DNA demethylation. As a "switch like" factor, 14-3-3η activated its downstream PI3K/Akt signal, which in turn promoted vascular endothelial growth factor (VEGF) production and secretion. As the characteristic fibrogenic paracrine factor regulated by B[a]P/14-3-3η, VEGF significantly induced the neovascularization and activation of hepatic stellate cells, leading to the development of hepatic fibrosis. Importantly, targeted 14-3-3η by using its specific inhibitor invented by our lab could prevent B[a]P-induced hepatic fibrosis, and could even reverse existent hepatic fibrosis caused by B[a]P. The present study not only revealed novel mechanisms, but also proposed an innovative approach for the targeted reversion/prevention of the harmful effects of exposure to PAHs on chronic liver disease.

Chronic arsenic exposure-provoked biotoxicity involved in liver-microbiota-gut axis disruption in chickens based on multi-omics technologies

INTRODUCTION

Arsenic has been ranked as the most hazardous substance by the U.S. Agency for Toxic Substances and Disease Registry. Environmental arsenic exposure-evoked health risks have become a vital public health concern worldwide owing to the widespread existence of arsenic. Multi-omics is a revolutionary technique to data analysis providing an integrated view of bioinformation for comprehensively and systematically understanding the elaborate mechanism of diseases.

OBJECTIVES

This study aimed at uncovering the potential contribution of liver-microbiota-gut axis in chronic inorganic arsenic exposure-triggered biotoxicity in chickens based on multi-omics technologies.

METHODS

Forty Hy-Line W-80 laying hens were chronically exposed to sodium arsenite with a dose-dependent manner (administered with drinking water containing 10, 20, or 30 mg/L arsenic, respectively) for 42 d, followed by transcriptomics, serum non-targeted metabolome, and 16S ribosomal RNA gene sequencing accordingly.

RESULTS

Arsenic intervention induced a serious of chicken liver dysfunction, especially severe liver fibrosis, simultaneously altered ileal microbiota populations, impaired chicken intestinal barrier, further drove enterogenous lipopolysaccharides translocation via portal vein circulation aggravating liver damage. Furtherly, the injured liver disturbed bile acids (BAs) homoeostasis through strongly up-regulating the BAs synthesis key rate-limiting enzyme CYP7A1, inducing excessive serum total BAs accumulation, accompanied by the massive synthesis of primary BA-chenodeoxycholic acid. Moreover, the concentrations of secondary BAs-ursodeoxycholic acid and lithocholic acid were markedly repressed, which might involve in the repressed dehydroxylation of Ruminococcaceae and Lachnospiraceae families. Abnormal BAs metabolism in turn promoted intestinal injury, ultimately perpetuating pernicious circle in chickens. Notably, obvious depletion in the abundance of four profitable microbiota, Christensenellaceae, Ruminococcaceae, Muribaculaceae, and Faecalibacterium, were correlated tightly with this hepato-intestinal circulation process in chickens exposed to arsenic.

CONCLUSION

Our study demonstrates that chronic inorganic arsenic exposure evokes liver-microbiota-gut axis disruption in chickens and establishes a scientific basis for evaluating health risk induced by environmental pollutant arsenic.

Suppressed Histone H3 Lysine 18 Acetylation Is Involved in Arsenic-Induced Liver Fibrosis in Rats by Triggering the Dedifferentiation of Liver Sinusoidal Endothelial Cells

Arsenic pollution is a global environmental concern. Arsenic-induced chronic liver injury and its irreversible outcomes, including liver cirrhosis and liver cancer, threaten the health of residents in arsenic-contaminated areas. Liver fibrosis is a reversible pathological stage in the progression of arsenic-induced chronic liver injury to cirrhosis and liver cancer. The aim of this study is to identify the epigenetic mechanism of arsenic-induced liver fibrosis based on the dedifferentiation of liver sinusoidal endothelial cells (LSECs). Rats were treated with 0.0, 2.5, 5.0, or 10.0 mg/kg sodium arsenite for 36 weeks. Marked fibrotic phenotypes were observed in the rat livers, manifested by hepatic stellate cell activation and an increased extracellular matrix, as well as the deposition of collagen fibers. The reduced fenestrations on the cells' surface and the increased expression of the dedifferentiation marker CD31 corroborated the LSECs' dedifferentiation in the liver tissue, which was also found to be significantly associated with fibrotic phenotypes. We further revealed that arsenic exposure could inhibit the enrichment of histone H3 lysine 18 acetylation (H3K18ac) in the promoters of Fcgr2b and Lyve1, two key genes responsible for maintaining the differentiation phenotype of LSECs. This inhibition subsequently suppressed the genes' expression, promoting LSEC dedifferentiation and subsequent liver fibrosis. In conclusion, arsenic can trigger liver fibrosis by inhibiting H3K18ac-dependent maintenance of LSEC differentiation. These findings uncover a novel mechanism of arsenic-induced liver fibrosis based on a new insight into epigenetically dependent LSEC dedifferentiation.

The Role of microRNAs in Arsenic-Induced Human Diseases: A Review

MicroRNAs (miRNAs) are noncoding RNAs with 20-22 nucleotides, which are encoded by endogenous genes and are capable of targeting the majority of human mRNAs. Arsenic is regarded as a human carcinogen, which can lead to many adverse health effects including diabetes, skin lesions, kidney disease, neurological impairment, male reproductive injury, and cardiovascular disease (CVD) such as cardiac arrhythmias, ischemic heart failure, and endothelial dysfunction. miRNAs can act as tumor suppressors and oncogenes via directly targeting oncogenes or tumor suppressors. Recently, miRNA dysregulation was considered to be an important mechanism of arsenic-induced human diseases and a potential biomarker to predict the diseases caused by arsenic exposure. Endogenic miRNAs such as miR-21, the miR-200 family, miR-155, and the let-7 family are involved in arsenic-induced human disease by inducing translational repression or RNA degradation and influencing multiple pathways, including mTOR/Arg 1, HIF-1α/VEGF, AKT, c-Myc, MAPK, Wnt, and PI3K pathways. Additionally, exogenous miRNAs derived from plants, such as miR-34a, miR-159, miR-2911, miR-159a, miR-156c, miR-168, etc., among others, can be transported from blood to specific tissue/organ systems in vivo. These exogenous miRNAs might be critical players in the treatment of human diseases by regulating host gene expression. This review summarizes the regulatory mechanisms of miRNAs in arsenic-induced human diseases, including cancers, CVD, and other human diseases. These special miRNAs could serve as potential biomarkers in the management and treatment of human diseases linked to arsenic exposure. Finally, the protective action of exogenous miRNAs, including antitumor, anti-inflammatory, anti-CVD, antioxidant stress, and antivirus are described.

Carbon Nitride-Based siRNA Vectors with Self-Produced O2 Effects for Targeting Combination Therapy of Liver Fibrosis via HIF-1α-Mediated TGF-β1/Smad Pathway

Hypoxia is an important feature, which can upregulate the hypoxia-inducible factor-1α (HIF-1α) expression and promote the activation of hepatic stellate cells (HSCs), leading to liver fibrosis. Currently, effective treatment for liver fibrosis is extremely lacking. Herein, a safe and effective method is established to downregulate the expression of HIF-1α in HSCs via targeted delivery of VA-PEG-modified CNs-based nanosheets-encapsulated (VA-PEG-CN@GQDs) HIF-1α small interfering RNA (HIF-1α-siRNA). Due to the presence of lipase in the liver, the reversible release of siRNA can be promoted to complete the transfection process. Simultaneously, VA-PEG-CN@GQD nanosheets enable trigger the water splitting process to produce O2 under near-infrared (NIR) irradiation, thereby improving the hypoxic environment of the liver fibrosis site and maximizing the downregulation of HIF-1α expression to improve the therapeutic effect, as demonstrated in liver fibrosis mice. Such combination therapy can inhibit the activation of HSCs via HIF-1α-mediated TGF-β1/Smad pathway, achieving outstanding therapeutic effects in liver fibrosis mice. In conclusion, this study proposes a novel strategy for the treatment of liver fibrosis by regulating the hypoxic environment and the expression of HIF-1α at lesion site.

A Novel Quinazoline Derivative Prevents and Treats Arsenic-Induced Liver Injury by Regulating the Expression of RecQ Family Helicase

Arsenic is a carcinogenic metalloid toxicant widely found in the natural environment. Acute or prolonged exposure to arsenic causes a series of damages to the organs, mainly the liver, such as hepatomegaly, liver fibrosis, cirrhosis, and even hepatocellular carcinoma. Therefore, it is imperative to seek drugs to prevent arsenic-induced liver injury. Quinazolines are a class of nitrogen heterocyclic compounds with biological and pharmacological effects in vivo and in vitro. This study was designed to investigate the ameliorating effects of quinazoline derivatives on arsenic-induced liver injury and its molecular mechanism. We investigated the mechanism of the quinazoline derivative KZL-047 in preventing and ameliorating arsenic-induced liver injury in vitro by cell cycle and apoptosis. We performed real-time fluorescence quantitative polymerase chain reaction (qPCR) and Western blotting combined with molecular docking. In vivo, the experiments were performed to investigate the mechanism of KZL-047 in preventing and ameliorating arsenic-induced liver injury using arsenic-infected mice. Physiological and biochemical indices of liver function in mouse serum were measured, histopathological changes in liver tissue were observed, and immunohistochemical staining was used to detect changes in the expression of RecQ-family helicases in mouse liver tissue. The results of in vitro experiments showed that sodium arsenite (SA) inhibited the proliferation of L-02 cells, induced apoptosis, blocked the cell cycle at the G1 phase, and decreased the expression of RecQ family helicase; after KZL-047 treatment in arsenic-induced L-02 cells, the expression of RecQ family helicase was upregulated, and the apoptosis rate was slowed, leading to the restoration of the cell viability level. KZL-047 inhibited arsenic-induced oxidative stress, alleviated oxidative damage and lipid peroxidation in vivo, and ameliorated arsenic toxicity-induced liver injury. KZL-047 restored the expression of RecQ family helicase proteins, which is consistent with the results of in vitro studies. In summary, KZL-047 can be considered a potential candidate for the treatment of arsenic-induced liver injury.

Radiofrequency Ablation-Induced Tumor Growth Is Suppressed by MicroRNA-21 Inhibition in Murine Models of Intrahepatic Colorectal Carcinoma

PURPOSE

To investigate the role of microRNA-21 (miR21) in radiofrequency (RF) ablation-induced tumor growth and whether miR21 inhibition suppresses tumorigenesis.

MATERIAL AND METHODS

Standardized liver RF ablation was applied to 35 C57/BL6 mice. miR21 and target proteins pSTAT3, PDCD4, and PTEN were assayed 3 hours, 24 hours, and 3 days after ablation. Next, 53 Balb/c and 44 C57BL/6 mice received Antago-miR21 or scrambled Antago-nc control, followed by intrasplenic injection of 10,000 CT26 or MC38 colorectal tumor cells, respectively. Hepatic RF ablation or sham ablation was performed 24 hours later. Metastases were quantified and tumor microvascular density (MVD) and cellular proliferation were assessed at 14 or 21 days after the procedures, respectively.

RESULTS

RF ablation significantly increased miR21 levels in plasma and hepatic tissue at 3 and 24 hours as well as target proteins at 3 days after ablation (P < .05, all comparisons). RF ablation nearly doubled tumor growth (CT26, 2.0 SD ± 1.0 fold change [fc]; MC38, 1.9 SD ± 0.9 fc) and increased MVD (CT26, 1.9 SD ± 1.0 fc; MC38, 1.5 ± 0.5 fc) and cellular proliferation (CT26, 1.7 SD ± 0.7 fc; MC38, 1.4 SD ± 0.5 fc) compared with sham ablation (P < .05, all comparisons). RF ablation-induced tumor growth was suppressed when Antago-miR21 was administered (CT26, 1.0 SD ± 0.7 fc; MC38, 0.9 SD ± 0.4 fc) (P < .01, both comparisons). Likewise, Antago-miR21 decreased MVD (CT26, 1.0 SD ± 0.3 fc; MC38, 1.0 SD ± 0.2 fc) and cellular proliferation (CT26, 0.9 SD ± 0.3 fc; MC38, 0.8 SD ± 0.3 fc) compared with baseline (P < .05, all comparisons).

CONCLUSIONS

RF ablation upregulates protumorigenic miR21, which subsequently influences downstream tumor-promoting protein pathways. This effect can potentially be suppressed by specific inhibition of miR21, rendering this microRNA a pivotal and targetable driver of tumorigenesis after hepatic thermal ablation.

Catalpol inhibits hepatic stellate cell activation by reducing the formation and changing the contents of hepatocyte-derived extracellular vesicles

Hepatic stellate cell (HSC) activation is the central event in hepatic fibrosis. The cross-talk between HSCs and hepatocytes, which is mediated by extracellular vesicles (EVs), affects HSC activation. This study aimed to investigate whether Catalpol (CTP) attenuated hepatic fibrosis via modulating EVs. Mice were injected intraperitoneally with CCl4 for 4 weeks to induce hepatic fibrosis. They were gavaged with CTP daily. Mouse serum EVs were isolated and identified using nanoparticle tracking analysis and transmission electron microscopy. Mouse hepatocytes (AML12) and primary HSCs were used to investigate the cell-to-cell crosstalk. The autophagosome-autolysosome fusion was determined using the autophagic flux assay. Hepatic fibrosis was attenuated by CTP, with a decrease of the myofibroblast marker, alpha-smooth muscle actin. The CTP treatment lowered the serum EVs. The co-culture of HSCs and the EVs derived from the CTP-treated mice or hepatocytes reduced HSC proliferation and the expressions of ACTA2 and Col1a1. After the CCl4 treatment, the autophagosomes in AML12 cells were increased, while the autolysosomes were reduced. The decrease of autophagic cargo receptor SQSTM1 in the CTP group suggested that autophagic degradation was sustained. After inhibiting the endogenous Rac1-GTP of hepatocytes, the co-culture of EVs and HSCs reduced Rac1-GTP. The Rac1-GTP level in serum EVs from the CTP-treated mice was reduced in vivo. CTP inhibited autophagy in hepatocytes by reducing Rac1-GTP and thus affect the amount of Rac1-GTP in hepatocyte-derived EVs and the formation of EVs, which attenuated hepatic fibrosis via inhibiting HSC activation.

Non-coding RNA therapeutics: Towards a new candidate for arsenic-induced liver disease

Arsenic, a metalloid toxicant, has caused serious environmental pollution and is presently a global health issue. Long-term exposure to arsenic causes diverse organ and system dysfunctions, including liver disease. Arsenic-induced liver disease comprises a spectrum of liver pathologies, ranging from hepatocyte damage, steatosis, fibrosis, to hepatocellular carcinoma. Various mechanisms, including an imbalance in redox reactions, mitochondrial dysfunction and epigenetic changes, participate in the pathogenesis of arsenic-induced liver disease. Altered epigenetic processes involved in its initiation and progression. Dysregulated modulations of non-coding RNAs (ncRNAs), including miRNAs, lncRNAs and circRNAs, exert regulating effects on these processes. Here, we have reviewed the underlying pathogenic mechanisms that lead to progressive arsenic-induced liver disease, and we provide a discussion focusing on the effects of ncRNAs on dysfunctions in intercellular communication and on the activation of hepatic stellate cells and malignant transformation of hepatocytes. Further, we have discussed the roles of ncRNAs in intercellular communication via extracellular vesicles and cytokines, and have provided a perspective for the application of ncRNAs as biomarkers in the early diagnosis and evaluation of the pathogenesis of arsenic-induced liver disease. Further investigations of ncRNAs will help us to understand the nature of arsenic-induced liver disease and to identify biomarkers and therapeutic targets.

Hepatoprotective and anti-hyperglycemic effects of ferulic acid in arsenic-exposed mice

Arsenic is a toxic metalloid that increases the risk of hepatotoxicity and hyperglycemia. The objective of the present study was to assess the effect of ferulic acid (FA) in mitigating glucose intolerance and hepatotoxicity caused by sodium arsenite (SA). A total of six groups including control, FA 100 mg/kg, SA 10 mg/kg, and groups that received different doses of FA (10, 30, and 100 mg/kg), respectively just before SA (10 mg/kg) for 28 days were examined. Fasting blood sugar (FBS) and glucose tolerance tests were conducted on the 29th day. On day 30, mice were sacrificed and blood and tissues (liver and pancreas) were collected for further investigations. FA reduced FBS and improved glucose intolerance. Liver function and histopathological studies confirmed that FA preserved the structure of the liver in groups received SA. Furthermore, FA increased antioxidant defense and decreased lipid peroxidation and tumor necrosis factor-alpha level in SA-treated mice. FA, at the doses of 30 and 100 mg/kg, prevented the decrease in the expression of PPAR-γ and GLUT2 proteins in the liver of mice exposed to SA. In conclusion, FA prevented SA-induced glucose intolerance and hepatotoxicity by reducing oxidative stress, inflammation, and hepatic overexpression of PPAR-γ and GLUT2 proteins.

Cigarette smoking, by accelerating the cell cycle, promotes the progression of non-small cell lung cancer through an HIF-1α-METTL3-m6A/CDK2AP2 axis

Cigarette smoking killed about 8 million people every year and promoted non-small cell lung cancer (NSCLC). We investigated the molecular mechanism of smoking-promoted NSCLC progression. Relative to non-smokers, NSCLC patients who were smokers had a higher tumor malignancy. For NSCLC cells, cigarette smoke extract (CSE) increased levels of HIF-1α, METTL3, Cyclin E1, and CDK2 and promoted the G1/S transition, which promoted cell proliferation. Down-regulation HIF-1α or METTL3 reversed these effects. meRIP-seq and RNA-seq revealed the m⁶A modification in Cyclin Dependent Kinase 2 Associated Protein 2 (CDK2AP2) mRNA as the key downstream target. Further, for NSCLC cells exposed to CSE, HIF-1α activated METTL3 transcription. Xenografts in nude mice demonstrated that HIF-1α via METTL3 participated in tumor growth. In NSCLC tissues of smokers, protein levels of HIF-1α and METTL3 were higher, and levels of CDK2AP2 were lower. In conclusion, HIF-1α via METTL3 regulation of the m⁶A modification of CDK2AP2 mRNA drives smoking-induced progression of NSCLC through promoting cell proliferation. This is a previously unknown molecular mechanism for smoking-induced NSCLC progression. The results have potential value for treatment of NSCLC, especially for patients who smoke.

Citicoline ameliorates arsenic-induced hepatotoxicity and diabetes in mice by overexpression of VAMP2, PPAR-γ, As3MT, and SIRT3

The use of arsenic in arsenic-based pesticides has been common in many countries in the past and today. There is considerable evidence linking arsenic exposure to hepatotoxicity and diabetes. Destructive phenomena such as hepatic oxidative stress and inflammation can interfere with glucose uptake and insulin function. In the present study, the antioxidant, anti-inflammatory, and molecular mechanism of citicoline against sodium arsenite-induced hepatotoxicity and glucose intolerance were investigated in mice. Citicoline improved glucose tolerance impaired by sodium arsenite. Citicoline increased the hepatic activity of catalase, superoxide dismutase, and glutathione peroxidase enzymes. Moreover, we found that citicoline prevents an increase in the levels of thiobarbituric acid reactive substances. Citicoline reduced levels of caspase 3, tumor necrosis factor-alpha, and interleukin 6 in sodium arsenite intoxicated groups. It was shown that citicoline increased the expression of arsenite methyltransferase, vesicle-associated membrane protein 2, peroxisome proliferator-activated receptor gamma, and sirtuin 3 to combat sodium arsenite toxicity. Citicoline reduced glucose intolerance, which was disrupted by sodium arsenite, by affecting the pancreatic and extra-pancreatic pathways involved in insulin production, secretion, and action. Based on our results, citicoline can be considered a modulating agent against arsenic-induced hepatotoxicity and hyperglycemia. Considering the relationship between arsenic exposure and the occurrence of side effects such as liver toxicity and diabetes, it is necessary to monitor and awareness of arsenic residues from sources such as drinking water.

Role of noncoding RNAs in liver fibrosis

Liver fibrosis is a wound-healing response following chronic liver injury caused by hepatitis virus infection, obesity, or excessive alcohol. It is a dynamic and reversible process characterized by the activation of hepatic stellate cells and excess accumulation of extracellular matrix. Advanced fibrosis could lead to cirrhosis and even liver cancer, which has become a significant health burden worldwide. Many studies have revealed that noncoding RNAs (ncRNAs), including microRNAs, long noncoding RNAs and circular RNAs, are involved in the pathogenesis and development of liver fibrosis by regulating signaling pathways including transforming growth factor-β pathway, phosphatidylinositol 3-kinase/protein kinase B pathway, and Wnt/β-catenin pathway. NcRNAs in serum or exosomes have been reported to tentatively applied in the diagnosis and staging of liver fibrosis and combined with elastography to improve the accuracy of diagnosis. NcRNAs mimics, ncRNAs in mesenchymal stem cell-derived exosomes, and lipid nanoparticles-encapsulated ncRNAs have become promising therapeutic approaches for the treatment of liver fibrosis. In this review, we update the latest knowledge on ncRNAs in the pathogenesis and progression of liver fibrosis, and discuss the potentials and challenges to use these ncRNAs for diagnosis, staging and treatment of liver fibrosis. All these will help us to develop a comprehensive understanding of the role of ncRNAs in liver fibrosis.

Activating Protein-1 (AP-1): A Promising Target for the Treatment of Fibrotic Diseases

The fibrosis of tissues and organs occurs via an aberrant tissue remodeling process characterized by an excessive deposition of extracellular matrix, which can lead to organ dysfunction, organ failure, and death. Because the pathogenesis of fibrosis remains unclear and elusive, there is currently no medication to reverse it; hence, this process deserves further study. Activating protein-1 (AP-1)-comprising Jun (c-Jun, JunB, JunD), Fos (c-fos, FosB, Fra1, and Fra2), and activating transcription factor-is a versatile dimeric transcription factor. Numerous studies have demonstrated that AP-1 plays a crucial role in advancing tissue and organ fibrosis via induction of the expression of fibrotic molecules and activating fibroblasts. This review focuses on the role of AP-1 in a range of fibrotic disorders as well as on the antifibrotic effects of AP-1 inhibitors. It also discusses the potential of AP-1 as a new therapeutic target in conditions involving tissue and organ fibrosis.

The lncRNA HOTAIR via miR-17-5p is involved in arsenite-induced hepatic fibrosis through regulation of Th17 cell differentiation

Arsenic compounds are toxins that are widely distributed in the environment. Chronic exposure to low levels of these compounds can cause hepatic fibrosis and other damage. Th17 differentiation of CD4⁺ T cells and the secretion of IL-17 activates hepatic stellate cells (HSCs), which are involved in hepatic fibrosis, but their mechanisms in arsenic-induced hepatic fibrosis are unclear. We found, in arsenite-induced fibrotic livers of mice, increases of CD4⁺ T cell infiltration, Th17 cell nuclear receptor retinoic acid receptor-related orphan receptor γt (RORγt), and secretion of the pro-inflammatory cytokine IL-17. There were also elevated levels of the lncRNA, HOTAIR. For Jurkat cells, arsenite elevated levels of HOTAIR and protein levels of RORγt and IL-17A, decreased miR-17-5p, promoted Th17 cell differentiation, and released IL-17. The culture medium of arsenite-treated Jurkat cells activated LX-2 cells. Down-regulation of HOTAIR or up-regulation of miR-17-5p blocked arsenite-induced Th17 cell differentiation, which inhibited the LX-2 cell activation. However, down-regulation of HOTAIR and miR-17-5p reversed this inhibitory effect. For mice, silencing of HOTAIR diminished the hepatic levels of RORγt and IL-17A and alleviated arsenite-induced hepatic fibrosis. These results demonstrate that, for CD4⁺ T cells, arsenite promotes RORγt-mediated Th17 cell differentiation through HOTAIR down-regulation of miR-17-5p, and increases the secretion of cytokine IL-17A, which activates HSCs; the activated HSCs facilitate hepatic fibrosis. The findings reveal a new mechanism and a potential therapeutic target for arsenite-induced hepatic fibrosis.

Atractylenolide III Ameliorated Autophagy Dysfunction via Epidermal Growth Factor Receptor-Mammalian Target of Rapamycin Signals and Alleviated Silicosis Fibrosis in Mice

Atractylenolide III (ATL-III) is a major active constituent of the natural plant Atractylodes rhizome. Our previous study has shown that ATL-III may alleviate alveolar macrophage apoptosis via the inhibition of the mammalian target of rapamycin (mTOR)-mediated autophagy of human silicosis. Therefore, we aimed to further explore the function of ATL-III in autophagy, apoptosis, and pulmonary fibrosis by establishing the ATL-III-intervened silicosis mouse model in this study. Meanwhile, we sought and then verified potential autophagy-related signaling pathways by matching differentially expressed genes (attained by RNA sequencing) and the autophagy database. In this study, RNA-sequencing results implied that the epidermal growth factor receptor, the crucial upstream activator of mTOR, was seen as a potential autophagy-regulatory molecule in the ATL-III-intervened silicosis mouse model. The finding of this study was that ATL-III might improve the disorder of autophagic degradation via the activation of epidermal growth factor receptor-mTOR signals in the pulmonary tissue of the silicosis mouse model. ATL-III also alleviated cell apoptosis and silicotic fibrosis. Overall, we supposed that ATL-III might be a potential protective medicine, which had a regulatory effect on autophagy, for the intervention of silicotic fibrosis. In the future, the therapeutic drugs for silicosis should be further focused on the development and application of such natural autophagy agents.

An update on animal models of liver fibrosis

The development of liver fibrosis primarily determines quality of life as well as prognosis. Animal models are often used to model and understand the underlying mechanisms of human disease. Although organoids can be used to simulate organ development and disease, the technology still faces significant challenges. Therefore animal models are still irreplaceable at this stage. Currently, in vivo models of liver fibrosis can be classified into five categories based on etiology: chemical, dietary, surgical, transgenic, and immune. There is a wide variety of animal models of liver fibrosis with varying efficacy, which have different implications for proper understanding of the disease and effective screening of therapeutic agents. There is no high-quality literature recommending the most appropriate animal models. In this paper, we will describe the progress of commonly used animal models of liver fibrosis in terms of their development mechanisms, applications, advantages and disadvantages, and recommend appropriate animal models for different research purposes.

Triamcinolone acetonide induces the autophagy of Ag85B-treated WI-38 cells via SIRT1/FOXO3 pathway

BACKGROUND

Tracheobronchial stenosis due to tuberculosis (TSTB) seriously threatens the health of tuberculosis patients. The inflammation and autophagy of fibroblasts affect the development of TSTB. Triamcinolone acetonide (TA) can regulate the autophagy of fibroblasts. Nevertheless, the impact of TA on TSTB and underlying mechanism has remained unclear.

OBJECTIVE

To study the impact of TA on TSTB and underlying mechanism.

MATERIAL AND METHODS

In order to simulate the TSTB-like model in vitro, WI-38 cells were exposed to Ag85B protein. In addition, the cell counting kit (CCK)-8 assay was applied to assess the function of TA in Ag85B-treated WI-38 cells. Quantitative real-time polymerase chain reaction was applied to detect the mRNA level of sirtuin 1 (SIRT1) and forkhead box O3 (FOXO3a), and autophagy-related proteins were evaluated by Western blot analysis. Vascular endothelial growth factor (VEGF) level was investigated by immunohistochemical staining. Enzyme-linked immunosorbent serologic assay was applied to detect the secretion of inflammatory cytokines. Furthermore, hematoxylin and eosin staining was applied to observe tissue injuries.

RESULTS

Ag85B affected WI-38 cell viability in a limited manner, while TA notably suppressed Ag85B-treated WI-38 cell viability. TA induced the apoptosis of Ag85B-treated WI-38 cells in a dose-dependent manner. In addition, Ag85B-treated WI-38 cells demonstrated the upregulation of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), interferon gamma (IFN-γ), and fibrotic proteins (transforming growth factor-beta [TGF-β] and vascular endothelial growth factor [VEGF]), which can be significantly destroyed by the TA. Meanwhile, TA reversed Ag85-induced inhibition of cell autophagy by mediation of p62, LC3, and Beclin1. Furthermore, silencing of SIRT1/FOXO3a pathway could reverse the effect of TA on the autophagy of Ag85B-treated cells.

CONCLUSION

TA significantly induced the autophagy of fibroblasts in Ag85B-treated cells by mediation of SIRT1/FOXO3 pathway. This study established a new theoretical basis for exploring strategies against TSTB.

Carthami flos extract against carbon tetrachloride-induced liver fibrosis via alleviating angiogenesis in mice

BACKGROUND

Angiogenesis is a pathological phenomenon contribute to the development of chronic liver diseases, and anti-angiogenic therapy is an effective strategy to alleviate liver fibrosis. Carthami flos, a medicinal and edible herb, has the effects of improving blood circulation and regulating angiogenesis. However, the anti-angiogenic effect of Carthami flos in liver fibrosis remains unknown.

METHODS

We investigated the protective effect and therapeutic mechanism of Carthami flos extract (CFE) on carbon tetrachloride (CCl₄)-induced liver fibrosis in mice. The liver injury and collagen deposition were observed and evaluated by conducting HE, Masson, and Sirius red staining, testing the serum biochemical indexes (ALT, AST, ALP, γ-GT), and measuring the contents of HYP and four indexes of liver fiber (Col-IV, LN, HA, PC-III). Simultaneously, the expressions of α-SMA and Collagen-I were detected to determine the activation of hepatic stellate cells (HSCs). Subsequently, we measured the expressions of angiogenesis-related proteins such as PDGFRB, ERK1/2, p-ERK1/2, MEK, p-MEK, HIF-1α, VEGFA, VEGFR2, AKT and eNOS, and the mRNA levels of PDGFRB and VEGFA. Additionally, immunofluorescence staining and RT-qPCR assays were carried out to ascertain the expressions of continuous endothelial markers CD31, CD34 and vWF, and scanning electron microscope analysis was performed to observe the number of sinusoidal endothelial fenestrations.

RESULTS

Herein, we found that CFE could significantly reduce liver injury and collagen deposition, like the same effect of colchicine. CFE significantly alleviated CCl₄-induced liver injury and fibrosis, mainly manifested by reducing the levels of ALT, AST, ALP and γ-GT and decreasing the contents of HYP, Col-IV, LN, HA and PC-III. Additionally, CCl₄ promoted the activation of HSCs by increasing the expressions of α-SMA and Collagen-I, while CFE could rectify the condition. Moreover, CFE treatment prevented the CCl₄-induced the up-regulation of PDGFRB, p-MEK, p-ERK1/2, HIF-1α, VEGFA, VEGFR2, AKT and eNOS, suggesting that CFE might provide the protection against abnormal angiogenesis. In the meantime, the gradual disappearance of sinusoidal capillarization after CFE treatment was supported by the decreased the contents of CD31, CD34 and vWF, as well as the increased number of sinusoidal endothelial fenestrae.

CONCLUSION

In this study, the reduction of collagen deposition, the obstruction of HSCs activation, the inactivation of angiogenic signaling pathways and the weakening of hepatic sinusoidal capillarization jointly confirmed that CFE might be promising to resist angiogenesis in liver fibrosis via the PDGFRB/ERK/HIF-1α and VEGFA/AKT/eNOS signaling pathways. Nevertheless, as a potential therapeutic drug, the deeper mechanism of Carthami flos still needs to be further elucidated.

OGG1 in the Kidney: Beyond Base Excision Repair

8-Oxoguanine DNA glycosylase (OGG1) is a repair protein for 8-oxoguanine (8-oxoG) in eukaryotic atopic DNA. Through the initial base excision repair (BER) pathway, 8-oxoG is recognized and excised, and subsequently, other proteins are recruited to complete the repair. OGG1 is primarily located in the cytoplasm and can enter the nucleus and mitochondria to repair damaged DNA or to exert epigenetic regulation of gene transcription. OGG1 is involved in a wide range of physiological processes, such as DNA repair, oxidative stress, inflammation, fibrosis, and autophagy. In recent years, studies have found that OGG1 plays an important role in the progression of kidney diseases through repairing DNA, inducing inflammation, regulating autophagy and other transcriptional regulation, and governing protein interactions and functions during disease and injury. In particular, the epigenetic effects of OGG1 in kidney disease have gradually attracted widespread attention. This study reviews the structure and biological functions of OGG1 and the regulatory mechanism of OGG1 in kidney disease. In addition, the possibility of OGG1 as a potential therapeutic target in kidney disease is discussed.

miRNA-21, which disrupts metabolic reprogramming to facilitate CD4+ T cell polarization toward the Th2 phenotype, accelerates arsenite-induced hepatic fibrosis

Elevated levels of arsenic may be present in groundwater, and long-term exposure to arsenic increases hepatic fibrosis. T helper 2 (Th2) cells are involved in the fibrotic cascade, and cell metabolism is a regulatory factor participating in CD4⁺ T cell differentiation and function. However, the mechanism for Th2 cell regulation of arsenite-induced hepatic fibrosis is not fully understood. In present study, for arsenite-fed mice, activated hepatic stellate cells may be involved in the infiltration of CD4⁺ T cells, accompanied by up-regulation of GATA3, a transcription factor, and IL-13, the major Th2 cytokine. Exposed to arsenite, Jurkat cells had increased aerobic glycolysis to promote the cell cycle and cell proliferation. Further, this process elevated levels of marker molecules, including those of the Th2 paradigm characterized by GATA3, IL-4, and IL-13. LX-2 cells were activated when treated with culture medium from Jurkat cells exposed to arsenite. miR-21 may be a therapeutic target for arsenite-induced hepatic fibrosis. In vitro, miR-21 knock-down caused inhibition of the PTEN/PI3K/AKT pathway induced by arsenite. It also reversed the elevated glycolysis and the accelerated cell cycle and cell proliferation. Indeed, this alteration led to diminished expression of GATA3, IL-4, and IL-13 in T cells differentiated under Th2 conditions, which inhibits activation of LX-2 cells. Consistent with the results in vitro, miR-21 knock-out in mice reversed hepatic fibrosis and attenuated the levels of GATA3 and IL-13 induced by arsenite. These findings indicate that miR-21 regulates the glycolysis of CD4⁺ T cells through the PTEN/PI3K/AKT pathway to accelerate the cell cycle, thereby facilitating CD4⁺ T cell polarization toward Th2 and releasing the fibrogenic factor IL-13, which participates in arsenite-associated hepatic fibrosis. Inhibition of Th2 polarization of CD4⁺T cells or miR-21 could be a therapeutic strategy to combat hepatic fibrosis caused by exposure to arsenic.

Hydrogen sulfide and miR21 are suitable biomarkers of hypoxic exposure

Hypoxia is the reduction of alveolar partial pressure of oxygen ([Formula: see text]). Military members and people who practice recreational activities from moderate to high altitudes are at risk for hypoxic exposure. Hypoxemia's signs and symptoms vary from asymptomatic to severe responses, such as excessive hypoxic ventilatory responses and residual neurobehavioral impairment. Therefore, it is essential to identify hypoxia-induced biomarkers to indicate people with exposure to hypoxia. Advances have been made in understanding physiological responses to hypoxia, including elevations in circulating levels of endothelin 1 (ET-1) and microRNA 21 (miR-21) and reduction in circulating levels of hydrogen sulfide (H2S). Although the levels of these factors change upon exposure to hypoxia, it is unclear if these changes are sustained on return to normoxia. We hypothesize that hypoxia-induced ET-1 and miR-21 remain elevated, whereas hypoxia-reduction in H2S sustains after returning to normoxic conditions. To test this hypothesis, we exposed male rats to 6 h of 12% O2 and measured circulating levels of ET-1 and miR-21, pre, during, and posthypoxia. We found that ET-1 plasma levels increased in response to hypoxia but returned to normal levels within 30 min after the restoration of normoxia. miR-21 plasma levels and transdermal H2S emissions decreased in response to hypoxia, remaining decreased on return to normoxia, thus following the biomarker criteria. Therefore, this study supports a unique role for plasma miR21 and transdermal H2S as hypoxia biomarkers that could be used to identify individuals after exposure to hypoxia.

Hepatic HRC induces hepatocyte pyroptosis and HSCs activation via NLRP3/caspase-1 pathway

The histidine-rich calcium-binding protein (HRC) is a regulator of Ca2 + homeostasis and it plays a significant role in liver fibrosis. Pyroptosis, a specific inflammatory cell death, can lead to hepatic stellate cells (HSCs) activation and liver fibrosis. However, the role of HRC in pyroptosis has not been explored. In this study, we demonstrated that HRC, mainly located in the hepatocyte, was over expressed in fibrotic liver tissues. We further found that enforced expression of HRC in hepatocytes induced pyroptosis and HMGB1 release, and subsequently led to HSCs activation by NLRP3/caspase-1 pathway. In addition, the proliferation and migration of HSCs were also enhanced by HRC overexpression in hepatocytes. Furthermore, NLRP3 inhibitor MCC950 and caspase-1 inhibitor VX-765 alleviated hepatic HRC-mediated hepatocytes pyroptosis and HSCs activation. This study demonstrated that hepatic HRC promoted HSCs activation by inducing hepatocyte pyroptosis, which suggests that HRC may be a promising therapeutic target to prevent liver fibrosis.

The Berberis vulgaris L. extract berberine exerts its anti-oxidant effects to ameliorate cholesterol overloading-induced cell apoptosis in the primary mice hepatocytes: an in vitro study

Cholesterol overloading stress damages normal cellular functions in hepatocytes and induces metabolic disorders to facilitate the development of multiple diseases, including cardiovascular diseases, which seriously degrades the life quality of human beings. Recent data suggest that the Berberis vulgaris L. extract berberine is capable of regulating cholesterol homeostasis, which is deemed as potential therapeutic drug for the treatment of cholesterol overloading-associated diseases, but its detailed functions and molecular mechanisms are still largely unknown. In the present study, we evidenced that berberine suppressed cell apoptosis in high-cholesterol-diet mice liver and cholesterol-overloaded mice hepatocytes. Also, cholesterol overloading promoted reactive oxygen species (ROS) generation to trigger oxidative damages in hepatocytes, which were reversed by co-treating cells with both berberine and the ROS scavenger N-acetylcysteine (NAC). Moreover, the underlying mechanisms were uncovered, and we validated that berberine downregulated Keap1, and upregulated Nrf2 to activate the anti-oxidant Nrf2/HO-1 signaling pathway in cholesterol overloading-treated hepatocytes, and both Keap1 upregulation and Nrf2 downregulation abrogated the suppressing effects of berberine on cell apoptosis in the hepatocytes with cholesterol exposure. Taken together, we concluded that berberine activated the anti-oxidant Keap1/Nrf2/HO-1 pathway to eliminate cholesterol overloading-induced oxidative stress and apoptotic cell death in mice hepatocytes, and those evidences hinted that berberine might be used as putative therapeutic drug for the treatment of cholesterol overloading-associated cardiovascular diseases.

The imminent role of microRNAs in salivary adenoid cystic carcinoma

Unfortunately, despite the severe problem associated with salivary adenoid cystic carcinoma (SACC), it has not been studied in detail yet. Therefore, the time has come to understand the oncogenic cause of SACC and find the correct molecular markers for diagnosis, prognosis, and therapeutic target to tame this disease. Recently, we and others have suggested that non-coding RNAs, specifically microRNAs and long non-coding RNAs, can be ideal biomarkers for cancer(s) diagnosis and progression. Herein, we have shown that various miRNAs, like miR-155, miR‑103a‑3p, miR-21, and miR-130a increase the oncogenesis process, whereas some miRNAs such as miR-140-5p, miR-150, miR-375, miR-181a, miR-98, miR-125a-5p, miR-582-5p, miR-144-3p, miR-320a, miR-187 and miR-101-3p, miR-143-3p inhibit the salivary adenoid cystic carcinoma progression. Furthermore, we have found that miRNAs also target many vital genes and pathways like mitogen-activated protein kinases-snail family transcriptional repressor 2 (MAPK-Snai2), p38/JNK/ERK, forkhead box C1 protein (FOXC1), mammalian target of rapamycin (mTOR), integrin subunit beta 3 (ITGB3), epidermal growth factor receptor (EGFR)/NF-κB, programmed cell death protein 4 (PDCD4), signal transducer and activator of transcription 3 (STAT3), neuroblastoma RAS (N-RAS), phosphatidylinositol-3-kinase (PI3K)/Akt, MEK/ERK, ubiquitin-like modifier activating enzyme 2 (UBA2), tumor protein D52 (TPD52) which play a crucial role in the regulation of salivary adenoid cystic carcinoma. Therefore, we believe that knowledge from this manuscript will help us find the pathogenesis process in salivary adenoid cystic carcinoma and could also give us better biomarkers of diagnosis and prognosis of the disease.

Mesenchymal Stem Cell-Derived Exosomes: A Promising Therapeutic Agent for the Treatment of Liver Diseases

Liver disease has become a major global health and economic burden due to its broad spectrum of diseases, multiple causes and difficult treatment. Most liver diseases progress to end-stage liver disease, which has a large amount of matrix deposition that makes it difficult for the liver and hepatocytes to regenerate. Liver transplantation is the only treatment for end-stage liver disease, but the shortage of suitable organs, expensive treatment costs and surgical complications greatly reduce patient survival rates. Therefore, there is an urgent need for an effective treatment modality. Cell-free therapy has become a research hotspot in the field of regenerative medicine. Mesenchymal stem cell (MSC)-derived exosomes have regulatory properties and transport functional "cargo" through physiological barriers to target cells to exert communication and regulatory activities. These exosomes also have little tumorigenic risk. MSC-derived exosomes promote hepatocyte proliferation and repair damaged liver tissue by participating in intercellular communication and regulating signal transduction, which supports their promise as a new strategy for the treatment of liver diseases. This paper reviews the physiological functions of exosomes and highlights the physiological changes and alterations in signaling pathways related to MSC-derived exosomes for the treatment of liver diseases in some relevant clinical studies. We also summarize the advantages of exosomes as drug delivery vehicles and discuss the challenges of exosome treatment of liver diseases in the future.

Transcriptomic analysis of bladder tissue in a rat model of ketamine-induced bladder fibrosis

INTRODUCTION

Ketamine-induced cystitis (KIC) is a disease caused by ketamine that can cause lower urinary tract symptoms (LUTS). Its end-stage is bladder contracture, which is related to bladder fibrosis and poses a serious burden to patient lives.

METHODS

We established a KIC model in female Sprague Dawley rats and verified bladder fibrosis in the model by Masson trichrome staining and western blot analysis. The bladders of the rats from the ketamine and control groups were used to perform transcriptome analysis. In particular, association analysis with metabolomics was also used to determine the potential mechanisms of ketamine-induced bladder fibrosis.

RESULTS

A total of 685 differentially expressed messenger RNAs, 71 differentially expressed long noncoding RNAs, 23 differentially expressed microRNAs, and 68 differentially expressed circular RNAs were identified. We found that ribosome, Wnt signaling, vascular endothelial growth factor signaling, cytoskeleton organization, and cytoskeletal protein binding may be potential pathways in ketamine-induced bladder fibrosis as identified by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. In addition, the mitogen-activated protein kinase pathway appeared to be closely related to the development of ketamine-induced bladder fibrosis according to association analysis.

CONCLUSIONS

In this study, using transcriptomic and correlation analyses of metabolomics, we identified pathways that may be potential targets for the prevention and treatment of ketamine-induced bladder fibrosis.

Extraction kinetic model of polysaccharide from Codonopsis pilosula and the application of polysaccharide in wound healing

The crude polysaccharide (CPNP) of Codonopsis pilosula was obtained by hot-water extraction technology. The extraction kinetic model established according to Fick's first law of diffusion and related parameters of polysaccharide was studied. CPNP microcapsules were prepared by blending with sodium alginate, Ca2+ ions and crude CPNP. The quality control (Drug loading rate, embedding rate and release rate, etc) of CPNP microcapsules were analyzed by pharmacopeas standards. The structure feature of CPNP microcapsules also were determined with various methods. The wound healing ability of CPNP microcapsules loading with different concentration of CPNP was evaluated using the rat wound model. The activity of various enzymes and the expression levels of pro-inflammatory factors in the model skin tissue also were determined by enzyme linked immunosorbent assay (ELISA). Hematoxylin-eosin staining (HE), Masson, immunohistochemistry were used to investigate the external application effect of CPNP microcapsules on skin wound repair. The extraction kinetics of CPNP was established with the linear correlation coefficient (R2) of 0.83-0.93, implied that the extraction process was fitted well with the Fick's first law of diffusion. The CPNP has good compatibility with sodium alginate and Ca2+ ions by SEM and TEM observation, and the particle size of CPNP microcapsules was 21.25±2.84 μm with the good degradation rate, loading rate (61.59%) and encapsulation rate (55.99%), maximum swelling rate (397.380 ±25.321%). Compared with control group, the redness, and swelling, bleeding, infection, and exudate of the damaged skin decreased significantly after CPNP microcapsules treatment, and the CPNP microcapsules groups exhibited good wound healing function with less inflammatory cell infiltration. The pathological structure showed that in the CPNP microcapsules group, more newborn capillaries, complete skin structure, and relatively tight and orderly arrangement of collagen fibers were observed in the skin of rats. CPNP microcapsules could effectively inhibit the high expression of pro-inflammatory factors in damaged skin, and significantly increase the contents of related enzymes (GSH-Px, T-AOC, LPO) and collagen fibers. The relative expression levels of genes (VEGF and miRNA21) in the CPNP microcapsules group were higher than those in the model group and the negative group. The above results suggested that the CPNP microcapsules could controlled-release the CPNP to the wound surface, and then played a better role in antibacterial, anti-inflammatory and skin wound repair.

Involvement of parathyroid hormone-related peptide in the aggressive phenotype of colorectal cancer cells

Colorectal cancer (CRC) remains one of the leading causes of mortality from malignant diseases worldwide. In general terms, CRC presents high heterogeneity due to the influence of different genetic and environmental factors; also, the neoplastic cells are strongly influenced by the extracellular matrix and several surrounding cells, known together as the tumor microenvironment (TME). Bidirectional communication takes place between the tumor and the TME through the release of autocrine and paracrine factors. Parathyroid hormone-related peptide (PTHrP) is a cytokine secreted by a wide variety of tissues and is able to regulate several cellular functions both in physiological as well as in pathological processes. It exerts its effects as a paracrine/autocrine factor, although its mode of action is mainly paracrine. It has been shown that this peptide is expressed by several tumors and that the tumor secretion of PTHrP is responsible for the malignant humoral hypercalcemia. Eight years ago, when our research group started studying PTHrP effects in the experimental models derived from intestinal tumors, the literature available at the time addressing the effects of PTHrP on colorectal tumors was limited, and no articles had been published regarding to the paracrine action of PTHrP in CRC cells. Based on this and on our previous findings regarding the role of PTH in CRC cells, our purpose in recent years has been to explore the role of PTHrP in CRC. We analyzed the behavior of CRC cells treated with exogenous PTHrP, focalizing in the study of the following events: Survival, cell cycle progression and proliferation, migration, chemoresistance, tumor-associated angiogenesis, epithelial to mesenchymal transition program and other events also associated with invasion, such us the induction of cancer stem cells features. This work summarizes the major findings obtained by our investigation group using in vitro and in vivo CRC models that evidence the participation of PTHrP in the acquisition of an aggressive phenotype of CRC cells and the molecular mechanisms involved in these processes. Recently, we found that this cytokine induces this malignant behavior not only by its direct action on these intestinal cells but also through its influence on cells derived from TME, promoting a communication between CRC cells and surrounding cells that contributes to the molecular and morphological changes observed in CRC cells. These investigations establish the basis for our next studies in order to address the clinical applicability of our findings. Recognizing the factors and mechanisms that promote invasion in CRC cells, evasion to the cytotoxic effects of current CRC therapies and thus metastasis is decisive for the identification of new markers with the potential to improve early diagnosis and/or to predict prognosis, to predetermine drug resistance and to provide treatment guidelines that include targeted therapies for this disease.

Profiles of messenger RNAs and MicroRNAs in hypoxia-induced hepatic stellate cells

Background

MicroRNA (miRNA) plays an important role in hepatic stellate cell (HSCs) activation and liver fibrosis. The purpose of this study is to explore the effect of hypoxia on the differential expression of mRNAs and miRNAs in rat HSCs.

Methods

HSC-T6 cells were treated with cobalt chloride (CoCl₂), and the activity of HSC-T6 cells was measured by the CCK-8 assay. The mRNA expression levels of hypoxia inducible factor-1α (HIF-1α), collagen type I, transforming growth factor-β1 (TGF-β1), and Smad7 were measured by RT-qPCR. The protein expression levels of HIF-1α, Bax, Bcl-2, and caspase-3 were assayed by western blot. We used basal medium and 400 µmol/L CoCl₂ medium to treat HSC-T6 cells for 48 h. Cells were harvested after 48 h to extract RNA. Transcriptome sequencing was performed to investigate differentially expressed miRNAs and mRNAs (fold change >2; P<0.05). Bioinformatics analysis was performed to predict the functions of differentially expressed miRNAs and mRNAs. Further, we used RT-qPCR to detect the expression of mRNAs and miRNAs to confirm the accuracy of sequencing.

Results

With the increase of CoCl₂ concentration, the activity of HSC-T6 cells decreased (P<0.05). The mRNA expression levels of HIF-1α, collagen I, TGF-β1, and Smad7, and the protein expressions levels of HIF-1α, Bax, caspase-3, and the Bcl-2/Bax ratio were increased compared with the control group (P<0.05), while the expression of Bcl-2 decreased. A total of 54 miRNAs (20 upregulated and 34 downregulated) and 1,423 mRNAs (685 upregulated and 738 downregulated) were differentially expressed in the 400 µmol/L CoCl₂ medium group compared to the control basal medium group. Further bioinformatics analysis demonstrated that the differentially expressed mRNAs and miRNAs were mainly enriched in the synthesis of extracellular matrix. In addition, we used RT-qPCR to detect the expression of mRNAs and miRNAs to confirm the accuracy of sequencing.

Conclusions

Our results presented the profiles of mRNAs and miRNAs in hypoxia-induced HSC-T6 cells in rats, the signaling pathways, and co-expression networks. These findings may suggest novel insights for the early diagnosis and treatment of HSC activation and liver fibrosis.

Macrophages regulates the transition of pericyte to peritoneal fibrosis through the GSDMD/IL-1β axis

BACKGROUND

End stage renal disease (ESRD) has caused public health problem with high prevalence worldwide. Peritoneum from peritoneal dialysis patients with ESRD can induce pathological changes of the peritoneum, including fibrosis. The trans-differentiation of pericytes has been found to be closely associated with inflammatory diseases, such as organ fibrosis. However, the function of macrophages in regulating the transition of pericyte to peritoneal fibrosis is unclear.

METHODS

Histological examination was conducted using Hematoxylin and eosin (HE) staining and Masson's trichrome staining. The protein levels were determined via western blot. Enzyme-linked immunosorbent assay (ELISA) was used to examine IL-1β concentrations. Gasdermin D (GSDMD) was knocked out in mice by Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-Associated 9 (CRISPR-Cas9).

RESULTS

Mice receiving dextrose peritoneal dialysate displayed mesothelial cell monolayer loss and thickness of submesothelial compact zone increase. Moreover, dextrose peritoneal dialysate treatment up-regulated GSDMD expression. GSDMD knockdown inhibited IL-1β production in macrophages. Further, pericytes were treated with cultural supernatant from macrophages. We found that GSDMD knockdown suppressed fibrosis and vascular endothelial growth factor (VEGF)/phosphoinositide 3-kinase (PI3K) pathway in pericytes. In addition, GSDMD were knocked out in mice using CRISPR/Cas9. The histological examinations revealed that GSDMD-/- alleviated the damage of peritoneal tissue and thickness of submesothelial compact zone. GSDMD-/- attenuated interleukin-1beta (IL-1β) level and peritoneal fibrosis induced by dextrose peritoneal dialysate treatment in pericytes in vivo.

CONCLUSION

These results demonstrated that macrophages can regulate the transition of pericyte to peritoneal fibrosis via the GSDMD/IL-1β axis, which provides a new therapeutic target.

Gill oxidative damage caused by acute ammonia stress was reduced through the HIF-1α/NF-κb signaling pathway in golden pompano (Trachinotus ovatus)

This study aimed to investigate the intoxication mechanism of golden pompano (Trachinotus ovatus) exposed to high ammonia levels and the effects on the immune and antioxidant mechanisms of gills. Juvenile golden pompano was exposed to ammonia (total ammonia: 26.9 mg/L) to induce 96 h of ammonia stress, and a 96 h recovery experiment was performed after poisoning. Then, we evaluated hematological parameters, the histological structure and the expression of related genes. In this experiment, continuous exposure to high levels of ammonia led to a significant increase in plasma alkaline phosphatase (ALP), acid phosphatase (ACP) and lactate dehydrogenase (LDH) levels (P < 0.05), and the levels of triiodothyronine (T3) and tetraiodothyronine (T4) were significantly reduced (P < 0.05). Moreover, the expression of antioxidant genes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and inflammatory cytokines such as tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) increased (P < 0.05). These results indicate that ammonia activates the active osmotic regulatory mechanism of fish gills and participates in defense and immune responses. However, with prolonged exposure to ammonia, the balance of the defense system is disrupted, leading to oxidative damage and inflammation of the gill tissue. This research not only helps elucidate the intoxication mechanism of golden pompano by ammonia at the molecular level but also provides a theoretical basis for further research on detoxification mechanisms.

Research progress of phenolic compounds regulating IL-6 to exert antitumor effects

Cytokine therapy, which activates the host immune system, has become an important and novel therapeutic approach to treat various cancers. Recent studies have shown that IL-6 is an important cytokine that regulates the homeostasis in vivo. However, excessive IL-6 plays a pathological role in a variety of acute and chronic inflammatory diseases, especially in cancer. IL-6 can transmit signals through JAK/STAT, RAS /MAPK, PI3K/ Akt, NF-κB, and other pathways to promote cancer progression. Phenolic compounds can effectively regulate the level of IL-6 in tumor cells and improve the tumor microenvironment. This article focuses on the phenolic compounds through the regulation of IL-6, participate in the prevention of cancer, inhibit the proliferation of cancer cells, reduce angiogenesis, improve therapeutic efficacy, and reduce side effects and other aspects. This will help to further advance research on cytokine therapy to reduce the burden of cancer and improve patient prognosis. However, current studies are mostly limited to animal and cellular experiments, and high-quality clinical studies are needed to further determine their antitumor efficacy in humans.

Dysregulation of MicroRNAs in Hypertrophy and Ossification of Ligamentum Flavum: New Advances, Challenges, and Potential Directions

Pathological changes in the ligamentum flavum (LF) can be defined as a process of chronic progressive aberrations in the nature and structure of ligamentous tissues characterized by increased thickness, reduced elasticity, local calcification, or aggravated ossification, which may cause severe myelopathy, radiculopathy, or both. Hypertrophy of ligamentum flavum (HLF) and ossification of ligamentum flavum (OLF) are clinically common entities. Though accumulated evidence has indicated both genetic and environmental factors could contribute to the initiation and progression of HLF/OLF, the definite pathogenesis remains fully unclear. MicroRNAs (miRNAs), one of the important epigenetic modifications, are short single-stranded RNA molecules that regulate protein-coding gene expression at posttranscriptional level, which can disclose the mechanism underlying diseases, identify valuable biomarkers, and explore potential therapeutic targets. Considering that miRNAs play a central role in regulating gene expression, we summarized current studies from the point of view of miRNA-related molecular regulation networks in HLF/OLF. Exploratory studies revealed a variety of miRNA expression profiles and identified a battery of upregulated and downregulated miRNAs in OLF/HLF patients through microarray datasets or transcriptome sequencing. Experimental studies validated the roles of specific miRNAs (e.g., miR-132-3p, miR-199b-5p in OLF, miR-155, and miR-21 in HLF) in regulating fibrosis or osteogenesis differentiation of LF cells and related target genes or molecular signaling pathways. Finally, we discussed the perspectives and challenges of miRNA-based molecular mechanism, diagnostic biomarkers, and therapeutic targets of HLF/OLF.