MicroRNA-181a regulates the activation of the NLRP3 inflammatory pathway by targeting MEK1 in THP-1 macrophages stimulated by ox-LDL

The emerging crosstalk between atherosclerosis-related microRNAs and Bermuda triangle of foam cells: Cholesterol influx, trafficking, and efflux

In atherosclerosis, the gradual buildup of lipid particles into the sub-endothelium of damaged arteries leads to numerous lipid alterations. The absorption of these modified lipids by monocyte-derived macrophages in the arterial wall leads to cholesterol accumulation and increases the likelihood of foam cell formation and fatty streak, which is an early characteristic of atherosclerosis. Foam cell formation is related to an imbalance in cholesterol influx, trafficking, and efflux. The formation of foam cells is heavily regulated by various mechanisms, among them, the role of epigenetic factors like microRNA alteration in the formation of foam cells has been well studied. Recent studies have focused on the potential interplay between microRNAs and foam cell formation in the pathogenesis of atherosclerosis; nevertheless, there is significant space to progress in this attractive field. This review has focused to examine the underlying processes of foam cell formation and microRNA crosstalk to provide a deep insight into therapeutic implications in atherosclerosis.

NLRP3 Inflammasome in Atherosclerosis: Putting Out the Fire of Inflammation

Atherosclerosis (AS) is a chronic inflammatory disease with thickening or hardening of the arteries, which led to the built-up of plaques in the inner lining of an artery. Among all the clarified pathogenesis, the over-activation of inflammatory reaction is one of the most acknowledged one. The nucleotide-binding domain leucine-rich repeat (NLR) and pyrin domain containing receptor 3 (NLRP3) inflammasome, as a vital and special form of inflammation and innate immunity, has been widely revealed to participate in the onset and development of AS. This review will introduce the process of the pathogenesis and progression of AS, and will describe the biological features of the NLRP3 inflammasome. Furthermore, the role of the NLRP3 inflammasome in AS and the possible mechanisms will be discussed. In addition, several kinds of agents with the effect of anti-atherosclerotic taking advantage of the NLRP3 inflammasome intervention will be described and discussed in detail, including natural compounds (baicalin, dihydromyricetin, luteolin, 5-deoxy-rutaecarpine (R3) and Salvianolic acid A, etc.), microRNAs (microRNA-30c-5p, microRNA-9, microRNA-146a-5p, microRNA-16-5p and microRNA-181a, etc.), and autophagy regulators (melatonin, dietary PUFA and arglabin, etc.). We aim to provide novel insights in the exploration of the specific mechanisms of AS and the development of new treatments of AS.

The Molecular Pathways of Pyroptosis in Atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory disease seriously endangering human health, whose occurrence and development is related to many factors. Pyroptosis is a recently identified novel programmed cell death associated with an inflammatory response and involved in the formation and progression of AS by activating different signaling pathways. Protein modifications of the sirtuin family and microRNAs (miRNAs) can directly or indirectly affect pyroptosis-related molecules. It is important to link atherosclerosis, thermogenesis and molecular modifications. This article will systematically review the molecular pathways of pyroptosis in AS, which can provide a new perspective for AS prevention and treatment.

Spotlight on NLRP3 Inflammasome: Role in Pathogenesis and Therapies of Atherosclerosis

Inflammation is an intricate biological response of body tissues to detrimental stimuli. Cardiovascular disease (CVD) is the leading cause of death worldwide, and inflammation is well documented to play a role in the development of CVD, especially atherosclerosis (AS). Emerging evidence suggests that activation of the NOD-like receptor (NLR) family and the pyridine-containing domain 3 (NLRP3) inflammasome is instrumental in inflammation and may result in AS. The NLRP3 inflammasome acts as a molecular platform that triggers the activation of caspase-1 and the cleavage of pro-interleukin (IL)-1β, pro-IL-18, and gasdermin D (GSDMD). The cleaved GSDMD forms pores in the cell membrane and initiates pyroptosis, inducing cell death and the discharge of intracellular pro-inflammatory factors. Hence, the NLRP3 inflammasome is a promising target for anti-inflammatory therapy against AS. In this review, we systematically summarized the current understanding of the activation mechanism of NLRP3 inflammasome, and the pathological changes in AS involving NLRP3. We also discussed potential therapeutic strategies targeting NLRP3 inflammasome to combat AS.

Serum MicroRNA Expression Patterns in Subjects After the 5-km Exercise Are Strongly Associated With Cardiovascular Adaptation

Circulating microRNAs (miRNAs) have been reported dysregulated during exercise. However, the changes of specific serum miRNAs during the 5-km run test with intensity of 51–52% maximum oxygen uptake (V̇O₂max) and their association with traditional cardiovascular-related indicators remain well-characterized. Levels of miR-1, miR-21, miR-146a, miR-155, miR-181, and miR-210 were detected in 120 young subjects before and after the exercise training by quantitative reverse-transcription PCR (RT-qPCR). Besides, the levels of cardiac troponin I (cTNI), myoglobin (Myo), creatine kinase (CK), creatine kinase-MB (CK-MB), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), ischemia-modified albumin (IMA), interleukin-6 (IL-6), and C-reactive protein (CRP) were measured and the correlation between levels of serum miRNAs and biochemical parameters was also analyzed. Compared with resting state, the serum levels of miR-1, miR-146a, miR-155, miR-181, and miR-210 were significantly increased after exercise training. Serum levels of miR-146a, miR-155, and miR-210 after exercise training were positively correlated with Myo, CK-MB, and LDH, respectively, while miR-1, miR-146a, miR-181, and miR-155 were positively correlated with the levels of IL-6. Additionally, all the five miRNAs were negatively correlated with IMA levels. The multivariate logistic regression analysis showed that high levels of miR-146a, AST, LDH, and IL-6 in serum were risk factors, while low IMA contents were a protective factor for cardiovascular adaptation during exercise. In conclusion, the dynamic changes of miRNAs under the condition of the 5-km continuous running contribute to the adaptive regulation of the cardiovascular function of the body.

C/EBPβ is a key transcription factor of ox-LDL inducing THP-1 cells to release multiple pro-inflammatory cytokines

OBJECTIVE

CCAAT/enhancer binding protein β (C/EBPβ) plays an important role during atherogenesis. However, how C/EBPβ functions remains unclear. In this study, we explore the relationship between C/EBPβ and oxidized LDL-induced multiple pro-inflammatory cytokines released in monocytes.

MATERIALS AND METHODS

THP-1 cells (human monocyte cell line) were stimulated by ox-LDL, ChIP was used to detect the binding function of C/EBPβ to target genes, small interfering RNA was used to knock down the expression of C/EBPβ, Western Blot was used to detect protein expression, and ChIP-seq was used to detect different groups of C/EBPβ bound gene fragments. The integrative genomics viewer (IGV), model-based analysis of ChIP-seq (MACS) were used to visualize the results of ChIP-seq. GO (gene ontology), KEGG (Kyoto Encyclopedia of Genes and Genomes) and Reactome data bases enrichment analysis were performed by the ClusterProfiler software. Ingenuity pathway analysis (IPA) was used to analyze the results of ChIP-seq and to summarize the data within the database.

RESULTS

We identified C/EBPβ as a key protein that regulated IL-1β, IL-6 through database. Then our results confirmed that C/EBPβ could bind directly to the gene of IL-18 and C/EBPβ plays a role in the increased expression and secretion of IL-18 protein after ox-LDL stimulation of THP-1. Using ChIP-seq, we found that the enhanced transcriptional function of C/EBPβ after ox-LDL treatment triggered changes in C/EBPβ-regulated downstream pathways. In the ChIP-seq results, we extracted inflammatory cytokines with significant expression differences, and by comparing them with the database of inflammatory cytokines that C/EBPβ directly regulated, we screened five inflammatory cytokines, CXCL8, IL17B, TNFSF11, CSF3, and CCL2, and the results showed that knockdown of C/EBPβ expression inhibited ox-LDL-induced secretion of CXCL8, TNFSF11, CSF3, and CCL2 by THP-1.

CONCLUSION

Our results suggest that ox-LDL stimulation enhances C/EBPβ-regulated transcription in THP-1 and C/EBPβ upregulate the release of multiple pro-inflammatory cytokines including IL-18, IL-1β, and IL-6 through direct binding to genes.

Myrtenal and β-caryophyllene oxide screened from Liquidambaris Fructus suppress NLRP3 inflammasome components in rheumatoid arthritis

Background

Liquidambaris Fructus (LF) is the infructescence of Liquidambar formosana. In Traditional Chinese Medicine, LF has been used to treat joint pain, a common symptom of arthritis and rheumatism; however, a lack of pharmacological evidence has limited its applications in modern clinics. Therefore, this study aims to explore the protective effect of LF on rheumatoid arthritis (RA) and to identify its active ingredients.

Methods

Rats with adjuvant-induced arthritis (AIA) were divided into 4 groups and administered petroleum ether extract of LF (PEL), ethyl acetate extract of LF (EEL), water extract of LF (WEL), or piroxicam (PIR) respectively for 3 weeks. Two additional groups were used as normal control (NC) and model control (MC) and administered distilled water as a placebo. The clinical scores for arthritis, bone surface, synovial inflammation and cartilage erosion were used to evaluate the therapeutic efficacy of each treatment. The serum IL-1β and TNF-α level and the expression of NLRP3, IL-1β and caspase-1 p20 in the synovial tissue of AIA rats were evaluated by ELISA and Western blot. The active ingredients of LF were investigated using network pharmacology and molecular docking methods, and their inhibition of NLRP3 inflammasome activation was verified in the human rheumatoid arthritis fibroblast-like synovial cells (RA-FLS) model.

Results

PEL could alleviate paw swelling, bone and joint destruction, synovial inflammation and cartilage erosion in the AIA rats, with significantly superior efficacy to that of EEL and WEL. PEL reduced IL-1β and TNF-α serum levels, and attenuated the upregulation of NLRP3, IL-1β and caspase-1 p20 expression in the synovial tissue of AIA rats. Network pharmacology and molecular docking results indicated that myrtenal and β-caryophyllene oxide were the main two active ingredients of PEL, and these two compounds showed significant inhibition on TNF-α, NLRP3, IL-1β and caspase-1 p20 expression in RA-FLS.

Conclusions

Myrtenal and β-caryophyllene oxide screened from PEL could suppress the activation of NLRP3 inflammasome, thereby alleviating RA symptoms.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03410-2.

Integrated Genomics Identifies miR-181/TFAM Pathway as a Critical Driver of Drug Resistance in Melanoma

MicroRNAs (miRNAs) are attractive therapeutic targets and promising candidates as molecular biomarkers for various therapy-resistant tumors. However, the association between miRNAs and drug resistance in melanoma remains to be elucidated. We used an integrative genomic analysis to comprehensively study the miRNA expression profiles of drug-resistant melanoma patients and cell lines. MicroRNA-181a and -181b (miR181a/b) were identified as the most significantly down-regulated miRNAs in resistant melanoma patients and cell lines. Re-establishment of miR-181a/b expression reverses the resistance of melanoma cells to the BRAF inhibitor dabrafenib. Introduction of miR-181 mimics markedly decreases the expression of TFAM in A375 melanoma cells resistant to BRAF inhibitors. Furthermore, melanoma growth was inhibited in A375 and M14 resistant melanoma cells transfected with miR-181a/b mimics, while miR-181a/b depletion enhanced resistance in sensitive cell lines. Collectively, our study demonstrated that miR-181a/b could reverse the resistance to BRAF inhibitors in dabrafenib resistant melanoma cell lines. In addition, miR-181a and -181b are strongly down-regulated in tumor samples from patients before and after the development of resistance to targeted therapies. Finally, melanoma tissues with high miR-181a and -181b expression presented favorable outcomes in terms of Progression Free Survival, suggesting that miR-181 is a clinically relevant candidate for therapeutic development or biomarker-based therapy selection.

MicroRNA‑1929‑3p participates in murine cytomegalovirus‑induced hypertensive vascular remodeling through Ednra/NLRP3 inflammasome activation

MicroRNAs (miRNAs) play an important role in the development of vascular remodeling in essential hypertension (EH) by mediating the effects of human cytomegalovirus (HCMV) on the vascular system. Therefore, the aim of the present study was to investigate the effects of murine cytomegalovirus (MCMV) infection on blood pressure and vascular function in mice, in order to elucidate the role of miR‑1929‑3p in this process. For model development, 7‑month‑old C57BL/6J mice were infected with the Smith strain of MCMV, and MCMV DNA, IgG and IgM were detected. Subsequently, blood pressure was measured via the carotid artery, and the morphological changes of the aorta were evaluated by hematoxylin and eosin and Masson's trichrome staining. miR‑1929‑3p transfection was performed using an adeno‑associated virus packaged vector and the changes in vascular structure were then observed. The levels of nitric oxide (NO) and endothelial NO synthase were also assessed with colorimetry. Vascular remodeling and expression of NLRP3 inflammasome pathway‑related proteins were detected by immunohistochemistry and western blotting. Endothelin‑1 (ET‑1), interleukin (IL)‑1β and IL‑18 were assayed by ELISA. The results revealed that MCMV infection increased the blood pressure, promoted vascular remodeling, caused endothelial cell injury, and downregulated miR‑1929‑3p. However, these effects were alleviated by miR‑1929‑3p overexpression, which downregulated endothelin A receptor (Ednra) and NLRP3 inflammasome, as well as endothelial injury‑ and vascular remodeling‑related genes. Taken together, the findings of the present study indicated that overexpression of miR‑1929‑3p may improve MCMV‑induced vascular remodeling, possibly via the deactivation of the NLRP3 inflammasome by ET‑1/Ednra.

The NLRP3 inflammasome: Multiple activation pathways and its role in primary cells during ventricular remodeling

Inflammasomes are a group of multiprotein signaling complexes located in the cytoplasm. Several inflammasomes have been identified, including NLRP1, NLRP2, NLRP3, AIM2, and NLRC4. Among them, NLRP3 was investigated in most detail, and it was reported that it can be activated by many different stimuli. Increased NLRP3 protein expression and inflammasome assembly lead to caspase-1 mediated maturation and release of IL-1β, which triggers inflammation and pyroptosis. The activation of the NLRP3 inflammasome has been widely reported in studies of tumors and neurological diseases, but relatively few studies on the cardiovascular system. Ventricular remodeling (VR) is an important factor contributing to heart failure (HF) after myocardial infarction (MI). Consequently, delaying VR is of great significance for improving heart function. Studies have shown that the NLRP3 inflammasome plays an essential role in the process of VR. Here, we reviewed the latest studies on the activation pathway of the NLRP3 inflammasome, focusing on the effects of the NLRP3 inflammasome in primary cells during VR, and finally discuss future research directions in this field.

LINC01140 Alleviates the Oxidized Low-Density Lipoprotein-Induced Inflammatory Response in Macrophages via Suppressing miR-23b

Our previous study has demonstrated that miR-23b enhances oxidized low-density lipoprotein (oxLDL)-induced inflammatory response of macrophages through the A20/NF-κB signaling pathway, thus contributing to atherosclerosis. This study aims to further investigate the upstream regulators of miR-23b in mediating oxLDL-induced inflammatory response. Human monocyte cell line THP1 was induced to differentiate into macrophages followed by the oxLDL stimulation of inflammatory response. The expression of miR-23b, LINC01140, and p53 mRNA was detected by quantitative PCR. The combination of miR-23b and LINC01140 was confirmed by luciferase reporter assay and RNA immunoprecipitation. The binding of p53 and LINC01140 promoter was determined by luciferase reporter assay. The level of inflammatory cytokines, including MCP-1, TNF-α, and IL-1β, was assessed by enzyme-linked immunosorbent assay. LINC01140 was downregulated, while p53 and miR-23b were upregulated in oxLDL-induced inflammatory response of macrophages. Overexpression of LINC01140 reduced NF-κB activity by reducing miR-23b and increasing A20. The transcription of LINC01140 was inhibited by binding of p53 and the LINC01140 promoter region. Knockdown of p53 significantly reduced NF-κB activity and level of inflammatory cytokines by promoting LINC01140 expression. Our findings demonstrated that LINC01140 acts as an anti-inflammatory factor through negatively regulating miR-23/A20 axis. In addition, p53 is identified as a transcriptional repressor of LINC01140.

Involvement of Myeloid Cells and Noncoding RNA in Abdominal Aortic Aneurysm Disease

Significance: Abdominal aortic aneurysm (AAA) is a potentially fatal condition, featuring the possibility of high-mortality rupture. To date, prophylactic surgery by means of open surgical repair or endovascular aortic repair at specific thresholds is considered standard therapy. Both surgical options hold different risk profiles of short- and long-term morbidity and mortality. Targeting early stages of AAA development to decelerate disease progression is desirable. Recent Advances: Understanding the pathomechanisms that initiate formation, maintain growth, and promote rupture of AAA is crucial to developing new medical therapeutic options. Inflammatory cells, in particular macrophages, have been investigated for their contribution to AAA disease for decades, whereas evidence on lymphocytes, mast cells, and neutrophils is sparse. Recently, there has been increasing interest in noncoding RNAs (ncRNAs) and their involvement in disease development, including AAA. Critical Issues: The current evidence on myeloid cells and ncRNAs in AAA largely originates from small animal models, making clinical extrapolation difficult. Although it is feasible to collect surgical human AAA samples, these tissues reflect end-stage disease, preventing examination of critical mechanisms behind early AAA formation. Future Directions: Gaining more insight into how myeloid cells and ncRNAs contribute to AAA disease, particularly in early stages, might suggest nonsurgical AAA treatment options. The utilization of large animal models might be helpful in this context to help bridge translational results to humans.

Fucoidan Inhibits NLRP3 Inflammasome Activation by Enhancing p62/SQSTM1-Dependent Selective Autophagy to Alleviate Atherosclerosis

NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation contributes to the progression of atherosclerosis, and autophagy inhibits inflammasome activation by targeting macrophages. We investigated whether fucoidan, a marine sulfated polysaccharide derived from brown seaweeds, could reduce NLRP3 inflammasome activation by enhancing sequestosome 1 (p62/SQSTM1)-dependent selective autophagy to alleviate atherosclerosis in high-fat-fed ApoE-/- mice with partial carotid ligation and differentiated THP-1 cells incubated with oxidized low-density lipoprotein (oxLDL). Fucoidan significantly ameliorated lipid accumulation, attenuated progression of carotid atherosclerotic plaques, deregulated the expression of NLRP3 inflammasome, autophagy receptor p62, and upregulated microtubule-associated protein light chain 3 (LC3)-II/I levels. Transmission electron microscopy and GFP-RFP-LC3 lentivirus transfection further demonstrated that fucoidan could activate autophagy. Mechanistically, fucoidan remarkably inhibited NLRP3 inflammasome activation, which was mostly dependent on autophagy. The inhibitory effects of fucoidan on NLRP3 inflammasome were enhanced by autophagy activator rapamycin (Rapa) and alleviated by autophagy inhibitor 3-methyladenine (3-MA). Fucoidan promoted the colocalization of NLRP3 and p62. Knockdown of p62 and ATG5 by small interfering RNA significantly reduced the inhibitory effects of fucoidan treatment on NLRP3 inflammasome. The data suggest that fucoidan can inhibit NLRP3 inflammasome activation by enhancing p62/SQSTM1-dependent selective autophagy to alleviate atherosclerosis.

MicroRNA sequences modulating inflammation and lipid accumulation in macrophage “foam” cells: Implications for atherosclerosis

Accumulation of macrophage “foam” cells, laden with cholesterol and cholesteryl ester, within the intima of large arteries, is a hallmark of early “fatty streak” lesions which can progress to complex, multicellular atheromatous plaques, involving lipoproteins from the bloodstream and cells of the innate and adaptive immune response. Sterol accumulation triggers induction of genes encoding proteins mediating the atheroprotective cholesterol efflux pathway. Within the arterial intima, however, this mechanism is overwhelmed, leading to distinct changes in macrophage phenotype and inflammatory status. Over the last decade marked gains have been made in understanding of the epigenetic landscape which influence macrophage function, and in particular the importance of small non-coding micro-RNA (miRNA) sequences in this context. This review identifies some of the miRNA sequences which play a key role in regulating “foam” cell formation and atherogenesis, highlighting sequences involved in cholesterol accumulation, those influencing inflammation in sterol-loaded cells, and novel sequences and pathways which may offer new strategies to influence macrophage function within atherosclerotic lesions.

A Novel Putative Role of TNK1 in Atherosclerotic Inflammation Implicating the Tyk2/STAT1 Pathway

Objective

Atherosclerosis is a chronic inflammatory disease which is responsible for many clinical manifestations. The present study was to investigate the anti-inflammatory functions and mechanisms of TNK1 in atherosclerosis.

Methods

The ApoE(-/-) mice and human carotid endarterectomy (CEA) atherosclerotic plaques were used to investigate the differential expression of TNK1. The ApoE(-/-) mice were fed with high-fat diet (HFD) or normal-fat diet (NFD) for 8 weeks; the aorta was separated and stained with oil red O to evaluate the formation of atherosclerosis. TNK1 in mice aorta was measured by qPCR. The human CEA were obtained and identified as ruptured and stable plaques. The level of TNK1 was measured by qPCR and Western-blot staining. Further studies were conducted in THP-1 cells to explore the anti-inflammatory effects of TNK1. We induced the formation of macrophages by incubating THP-1 cells with PMA (phorbol 12-myristate 13-acetate). Afterwards, oxidized low-density lipoprotein (oxLDL) was used to stimulate the inflammation, and the secretion of inflammatory factors was measured by ELISA and qPCR. The levels of TNK1, total STAT1 and Tyk2, and the phosphorylation of STAT1 and Tyk2 were measured by western blot to uncover the mechanisms of TNK1.

Results

The oil red O staining indicated obvious deposition of lipid on the aorta of ApoE(-/-) mice after 8-week HFD treatment. The TNK1 level was much higher in both the HFD-fed ApoE(-/-) mice aorta arch and the ruptured human CEA plaques. We found that TNK1 was highly expressed in THP-1 cells, compared to other atherosclerotic related cells (HUVEC, HBMEC, and HA-VSMC), indicating TNK1 might be involved in the inflammation. Suppressing the expression of TNK1 by shTNK1 inhibited the oxLDL-induced secretion of inflammatory factors, such as IL-12, IL-6, and TNF-α. ShTNK1 also inhibited the uptake of lipid and decreased the cellular cholesterol content in THP-1 cells. Furthermore, the shTNK1 suppressed the oxLDL-induced phosphorylation of Tyk2 and STAT1.

Conclusion

TNK1 participated in the inflammation in atherosclerosis. shTNK1 suppressed the oxLDL-induced inflammation and lipid deposition in THP-1 cells. The mechanism might be related to the Tyk2/STAT signal pathway.

Long non-coding RNA MEG3 promotes fibrosis and inflammatory response in diabetic nephropathy via miR-181a/Egr-1/TLR4 axis

Long non-coding RNAs (lncRNAs) play vital roles in diabetic nephropathy (DN). This research aimed to study the potential role and underlying molecular mechanisms of long non-coding RNA MEG3 in DN. We found that MEG3 was upregulated in DN in vivo and in vitro and could enhance cell fibrosis and inflammatory response in DN. MEG3 functioned as an endogenous sponge for miR-181a in mesangial cells (MCs) via direct targeting and in an Ago2-dependent manner. MiR-181a inhibition promoted MC fibrosis and inflammatory response. In addition, Egr-1 was confirmed as a target gene of miR-181a. Further investigations verified that MEG3 promotes fibrosis and inflammatory response via the miR-181a/Egr-1/TLR4 axis in vitro and in vivo. These results provide new insights into the regulation between MEG3 and the miR-181a/Egr-1/TLR4 signaling pathway during DN progression.

Differential Expression of MicroRNAs in Silent and Functioning Corticotroph Tumors

The potential role of miRNAs in the silencing mechanisms of pituitary neuroendocrine tumors (PitNETs) has not been addressed. The aim of the present study was to evaluate the expression levels and the potential associated role of some miRNAs, pathways, and transcription factors in the silencing mechanisms of corticotroph tumors (CTs). Accordingly, the expression of miR-375, miR-383, miR-488, miR-200a and miR-103; of PKA, MAP3K8, MEK, MAPK3, NGFIB, NURR1, PITX1, and STAT3 were analyzed via qRT-PCR in 23 silent and 24 functioning CTs. miR-200a and miR-103 showed significantly higher expression in silent than in functioning CTs, even after eliminating the bias of tumor size, therefore enabling the differentiation between the two variants. Additionally, miR-383 correlated negatively with TBX19 in silent CTs, a transcription factor related with the processing of POMC that can participate in the silencing mechanisms of CTs. Finally, the gene expression levels of miR-488, miR-200a, and miR-103 were significantly higher in macroadenomas (functioning and silent) than in microadenomas. The evidence from this study indicates that miRNAs could be involved in the pathophysiology of CTs. The translational implications of these findings suggest that pharmacological treatments specifically targeting these miRNAs could become a promising therapeutic option for these patients.

Cannabinoid Receptor 1/miR-30b-5p Axis Governs Macrophage NLRP3 Expression and Inflammasome Activation in Liver Inflammatory Disease

Nod-like receptor (NLR) family pyrin domain containing 3 (NLRP3) has been regarded as an important initiator or promoter in multiple inflammatory diseases. However, the relationship between cannabinoid receptor 1 (CB1) and macrophage NLRP3 inflammasome and the corresponding molecular mechanism in liver inflammation remain unclear. Mouse liver injury models were induced by carbon tetrachloride (CCl₄) or methionine-choline-deficient and high fat (MCDHF) diet. Human liver tissues were obtained from patients with different chronic liver diseases. CB1 expression was increased in liver tissue and macrophages of CCl₄- and MCDHF-treated mice, positively correlated with NLRP3. CB1 agonist ACEA (Arachiodonyl-2’-Chloroethylamide) promoted NLRP3 expression and NLRP3 inflammasome activation in macrophages. CB1 blockade with its antagonist AM281 reduced NLRP3 expression, inflammasome activation, and liver inflammation in CCl₄- and MCDHF-treated mice. MicroRNA-30b-5p (miR-30b-5p), screened by the intersection of bioinformatics databases and downregulated miRNAs in injured liver, negatively correlated with NLRP3 in mouse and human liver. miR-30b-5p was involved in CB1-mediated activation of NLRP3 inflammasome in macrophages by directly targeting NLRP3. Importantly, administration of miR-30b-5p agomir targeted NLRP3 and attenuated liver inflammation in the injured liver. Altogether, CB1/miR-30b-5p axis modulates NLRP3 expression and NLPR3 inflammasome activation in macrophages during liver inflammation, which provides a potential target for liver disease.

The Multifaceted Roles of Pyroptotic Cell Death Pathways in Cancer

Cancer is a category of diseases involving abnormal cell growth with the potential to invade other parts of the body. Chemotherapy is the most widely used first-line treatment for multiple forms of cancer. Chemotherapeutic agents act via targeting the cellular apoptotic pathway. However, cancer cells usually acquire chemoresistance, leading to poor outcomes in cancer patients. For that reason, it is imperative to discover other cell death pathways for improved cancer intervention. Pyroptosis is a new form of programmed cell death that commonly occurs upon pathogen invasion. Pyroptosis is marked by cell swelling and plasma membrane rupture, which results in the release of cytosolic contents into the extracellular space. Currently, pyroptosis is proposed to be an alternative mode of cell death in cancer treatment. Accumulating evidence shows that the key components of pyroptotic cell death pathways, including inflammasomes, gasdermins and pro-inflammatory cytokines, are involved in the initiation and progression of cancer. Interfering with pyroptotic cell death pathways may represent a promising therapeutic option for cancer management. In this review, we describe the current knowledge regarding the biological significance of pyroptotic cell death pathways in cancer pathogenesis and also discuss their potential therapeutic utility.