BRG1 attenuates colonic inflammation and tumorigenesis through autophagy-dependent oxidative stress sequestration

SMARCA4: Promises and challenges in the treatment of cancers

The SWI/SNF (switch/sucrose non-fermentable) related BAF (BRG1/BRM-related factor) chromatin remodeling complex subunit ATPase 4 (SMARCA4) is a gene with a high mutation frequency in the SWI/SNF complex. It plays a role as an ATP-dependent catalytic subunit, participates in remodeling chromatin structure and regulation of gene expression, and is closely related to the poor prognosis of malignant tumors. It is imperative to conduct a comprehensive investigation into the distinctive biological functions and mechanisms by which SMARCA4 contributes to cancer development and to devise targeted therapeutic strategies. Despite numerous studies associating SMARCA4 with the regulation of essential genes, ferroptosis, autophagy, lipid metabolism, and oxidative stress, the precise mechanisms of SMARCA4 in tumors remain unclear. Patients with SMARCA4 mutations exhibit a poor prognosis and demonstrate limited responsiveness to surgery, targeted therapies, immunotherapy, and chemotherapies. Thus, SMARCA4 emerges as a promising biomarker and therapeutic target. However, the development of more effective precision therapy tools remains an urgent unmet need. The unique molecular characteristics of SMARCA4 pose significant challenges for targeted drug development. Notably, the discovery of inhibitors targeting SMARCA4 synthetic lethal partners and associated pathways has marked a breakthrough in this field. Monotherapies directed against SMARCA4 face several limitations, including drug resistance, suboptimal objective response rates, and dose-limiting toxicities. Consequently, the exploration of combinatorial therapeutic strategies for SMARCA4 deficiency populations represents a critical direction for future clinical translation.

Harnessing Akkermansia muciniphila Membrane Coating for Probiotic Therapy in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBDs) are characterized by dysregulated inflammatory responses, increased reactive oxygen species (ROS), and compromised intestinal barrier function. Current clinical treatments often yield suboptimal responses and significant side effects. Given the great potential of Akkermansia muciniphila (AKK) bacterial membrane components in IBD treatment and the possible pathogenicity of live bacteria, to essentially address these challenges, we develop a natural membrane-based single-cell coating, incorporating a self-assembled AKK bacterial membrane (AKM) and astaxanthin (AST), forming a protective biological barrier on probiotics. Utilizing Escherichia coli Nissle 1917 (EcN) for the oral delivery system, we engineer AKM-AST@EcN nanocoated probiotics, demonstrating exceptional gastrointestinal (GI) tract tolerance and robust bioactivity. Critically, our findings highlight the potential of AKM-AST@EcN as a promising therapeutic approach for IBD treatment while also presenting a distinctive strategy for probiotic oral delivery systems.

BRG1 Deficiency Promotes Cardiomyocyte Inflammation and Apoptosis by Activating the cGAS-STING Signaling in Diabetic Cardiomyopathy

Brahma-related gene 1 (BRG1) has been implicated in the repair of DNA double-strand breaks (DSBs). Downregulation of BRG1 impairs DSBs repair leading to accumulation of double-stranded DNA (dsDNA). Currently, the role of BRG1 in diabetic cardiomyopathy (DCM) has not been clarified. In this study, we aimed to explore the function and molecular by which BRG1 regulates DCM using mice and cell models. We found that BRG1 was downregulated in the cardiac tissues of DCM mice and in cardiomyocytes cultured with high glucose and palmitic acid (HG/PA), which was accompanied by accumulation of dsDNA and activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway. shRNA-mediated Brg1 knockdown aggravated DCM mice cardiac functions, enhanced dsDNA accumulation, cGAS-STING signaling activation, which induced inflammation and apoptosis. In addition, the results were further verified in HG/PA-treated primary neonatal rat cardiomyocytes (NRCMs). Overexpression of BRG1 in NRCMs yielded opposite results. Furthermore, a selective cGAS inhibitor RU.521 or STING inhibitor C-176 partially reversed the BRG1 knockdown-induced inflammation and apoptosis in vitro. In conclusion, our results demonstrate that BRG1 is downregulated during DCM in vivo and in vitro, resulting in cardiomyocyte inflammation and apoptosis due to dsDNA accumulation and cGAS-STING signaling activation. Therefore, targeting the BRG1-cGAS-STING pathway may represent a novel therapeutic strategy for improving cardiac function of patients with DCM.

L-Arginine-Modified Selenium Nanozymes Targeting M1 Macrophages for Oral Treatment of Ulcerative Colitis

Ulcerative colitis (UC) involves persistent inflammation in the colon and rectum, with excessive reactive oxygen species (ROS) accumulation. This ROS buildup damages colonic epithelial cells and disrupts intestinal flora, worsening disease progression. Current antioxidant therapies are limited due to their instability in the gut and lack of targeting, hindering precise intervention at the lesion site. This study prepares an L-Arginine-modified selenium nanozyme (Se-CA) for the targeted oral treatment of UC. Se-CA specifically targets M1-type macrophages at sites of inflammation by binding to cationic amino acid transporter protein 2 on the surface of M1-type macrophages. In vitro studies show that Se-CA scavenges reactive ROS and reactive nitrogen species (RNS) in artificial gastric acid and intestinal fluids, and inhibits iron death in intestinal epithelial cells. In mice model of ulcerative colitis, oral administration of Se-CA is effective in the treatment of colitis through its anti-inflammatory and antioxidant properties, inhibition of iron death and regulation of intestinal flora. In conclusion, this work provides new insights into the targeted oral treatment of UC.

CRISPR/RNA Aptamer System Activated by an AND Logic Gate for Biomarker-Driven Theranostics

The development of an engineered RNA device capable of detecting multiple biomarkers to evaluate pathological states and autonomously implement responsive therapies is urgently needed. Here, we report InCasApt, an integrated nano CRISPR Cas13a/RNA aptamer theranostic platform capable of achieving both biomarker detection and biomarker-driven therapy. Within this system, a Cas13a/crRNA complex, a hairpin reporter (HR), a dinitroaniline caged Ce6 photosensitizer (Ce6-DN), and a DN-binding RNA aptamer precursor (DNBApt) are coloaded onto dendritic mesoporous silicon nanoparticles (DMSN) in a controlled manner. While InCasApt remains inert in normal cells, its programmable theranostic capabilities are activated in tumor cells that have elevated expression of carcinogenic miRNA-155 and miRNA-21. These miRNAs act as an AND logic gate, generating fluorescence for disease condition evaluation and ROS for photodynamic therapy. This process also upregulates antioncogene BRG1 and suppresses tumor migration by inhibiting the function of miRNA-155 and miRNA-21. These effects underscore the versatility of InCasApt as an miRNA-targeting strategy for bridging the gap between diagnosis and therapy.

BRG1 promotes liver cancer cell proliferation and metastasis by enhancing mitochondrial function and ATP5A1 synthesis through TOMM40

Hepatocellular carcinoma (HCC) is one of the most lethal malignant tumors worldwide. Brahma-related gene 1 (BRG1), as a catalytic ATPase, is a major regulator of gene expression and is known to mutate and overexpress in HCC. The purpose of this study was to investigate the mechanism of action of BRG1 in HCC cells. In our study, BRG1 was silenced or overexpressed in human HCC cell lines. Transwell and wound healing assays were used to analyze cell invasiveness and migration. Mitochondrial membrane potential (MMP) and mitochondrial permeability transition pore (mPTP) detection were used to evaluate mitochondrial function in HCC cells. Colony formation and cell apoptosis assays were used to evaluate the effect of BRG1/TOMM40/ATP5A1 on HCC cell proliferation and apoptosis/death. Immunocytochemistry (ICC), immunofluorescence (IF) staining and western blot analysis were used to determine the effect of BRG1 on TOMM40, ATP5A1 pathway in HCC cells. As a result, knockdown of BRG1 significantly inhibited cell proliferation and invasion, promoted apoptosis in HCC cells, whereas BRG1 overexpression reversed the above effects. Overexpression of BRG1 can up-regulate MMP level, inhibit mPTP opening and activate TOMM40, ATP5A1 expression. Our results suggest that BRG1, as an oncogene, promotes HCC progression by regulating TOMM40 affecting mitochondrial function and ATP5A1 synthesis. Targeting BRG1 may represent a new and effective way to prevent HCC development.

Regulatory Roles of SWI/SNF Chromatin Remodeling Complexes in Immune Response and Inflammatory Diseases

The switch/sucrose non-fermentable (SWI/SNF) chromatin remodeling complexes (also referred to as BAF complexes) are composed of multiple subunits, which regulate the nucleosome translocation and chromatin accessibility. In recent years, significant advancements have been made in understanding mutated genes encoding subunits of the SWI/SNF complexes in cancer biology. Nevertheless, the role of SWI/SNF complexes in immune response and inflammatory diseases continues to attract significant attention. This review presents a summary of the significant functions of SWI/SNF complexes during the overall process from the development to the activation of innate and adaptive immune cells. In addition, the correlation between various SWI/SNF subunits and diverse inflammatory diseases is explored. Further investigations are warranted in terms of the mechanism of SWI/SNF complexes' preference for binding sites and opposite pro-/anti-inflammatory effects. In conclusion, further efforts are needed to evaluate the druggability of targeting SWI/SNF complexes in inflammatory diseases, and we hope this review will inspire the development of novel immune modulators in clinical practice.

Advances in the study of the role of high-frequency mutant subunits of the SWI/SNF complex in tumors

SWI/SNF (Switch/Sucrose non-fermentable, switch/sucrose non-fermentable) chromatin remodeling complex is a macromolecular complex composed of multiple subunits. It can use the energy generated by the hydrolysis of ATP (Adenosine triphosphate) to destroy the connection between DNA and histones, achieve the breakdown of nucleosomes, and regulate gene expression. SWI/SNF complex is essential for cell proliferation and differentiation, and the abnormal function of its subunits is closely related to tumorigenesis. Among them, ARID1A, an essential non-catalytic subunit of the SWI/SNF complex, can regulate the targeting of the complex through DNA or protein interactions. Moreover, the abnormal function of ARID1A significantly reduces the targeting of SWI/SNF complex to genes and participates in critical intracellular activities such as gene transcription and DNA synthesis. As a catalytic subunit of the SWI/SNF complex, SMARCA4 has ATPase activity that catalyzes the hydrolysis of ATP to produce energy and power the chromatin remodeling complex, which is critical to the function of the SWI/SNF complex. The study data indicate that approximately 25% of cancers have one or more SWI/SNF subunit genetic abnormalities, and at least nine different SWI/SNF subunits have been identified as having repeated mutations multiple times in various cancers, suggesting that mutations affecting SWI/SNF subunits may introduce vulnerabilities to these cancers. Here, we review the mechanism of action of ARID1A and SMARCA4, the two subunits with the highest mutation frequency in the SWI/SNF complex, and the research progress of their targeted therapy in tumors to provide a new direction for precise targeted therapy of clinical tumors.

New insight in treating autoimmune diseases by targeting autophagy

Autophagy is a highly conserved biological process in eukaryotes, which degrades cellular misfolded proteins, damaged organelles and invasive pathogens in the lysosome-dependent manner. Autoimmune diseases caused by genetic elements, environments and aberrant immune responses severely impact patients' living quality and even threaten life. Recently, numerous studies have reported autophagy can regulate immune responses, and play an important role in autoimmune diseases. In this review, we summarised the features of autophagy and autophagy-related genes, enumerated some autophagy-related genes involved in autoimmune diseases, and further overviewed how to treat autoimmune diseases through targeting autophagy. Finally, we outlooked the prospect of relieving and curing autoimmune diseases by targeting autophagy pathway.

Moxibustion Regulates the BRG1/Nrf2/HO-1 Pathway by Inhibiting MicroRNA-222-3p to Prevent Oxidative Stress in Intestinal Epithelial Cells in Ulcerative Colitis and Colitis-Associated Colorectal Cancer

Oxidative stress is crucial in ulcerative colitis (UC) and colitis-associated colorectal cancer (CAC). Intestinal epithelial cells (IECs) are an important component of the intestinal barrier. In previous studies, we have demonstrated that suppressing microRNA-222-3p (miR-222-3p) can protect against oxidative stress in IECs, which ameliorates colonic injuries in UC mice and prevents the conversion of UC to CAC. In this case, we hope to explore whether moxibustion can alleviate UC and CAC by inhibiting miR-222-3p based on mouse models of UC and CAC. After herb-partitioned moxibustion (HPM) intervention, the disease activity index (DAI) and colon macroscopic damage index (CMDI) were significantly reduced in UC mice, and the number and volume of intestinal tumors were decreased considerably in CAC mice. Meanwhile, we found that HPM suppressed miR-222-3p expression and upregulated the mRNA and protein expression of Brahma-related gene 1 (BRG1), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), while inhibiting Kelch-like ECH-associated protein 1 (Keap1) expression in IECs of UC and CAC mice. With changes in reactive oxygen species (ROS), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and inflammatory cytokines interleukin (IL)-1β and tumor necrosis factor (TNF)-α), we verified that HPM protects against oxidative stress and inflammation in IECs of UC and CAC mice. The effect of HPM was inhibited in miR-222-3p overexpression mice, further demonstrating that the protective effect of HPM on UC and CAC mice was through inhibiting miR-222-3p. In summary, HPM regulates the BRG1/Nrf2/HO-1 pathway by inhibiting miR-222-3p to attenuate oxidative stress in IECs in UC and CAC.

Lysosomal dysfunction-derived autophagy impairment of gingival epithelial cells in diabetes-associated periodontitis with altered protein acetylation

Diabetes-associated periodontitis (DP) presents severe inflammation and resistance to periodontal conventional treatment, presenting a significant challenge in clinical management. In this study, we investigated the underlying mechanism driving the hyperinflammatory response in gingival epithelial cells (GECs) of DP patients. Our findings indicate that lysosomal dysfunction under high glucose conditions leads to the blockage of autophagy flux, exacerbating inflammatory response in GECs. Single-cell RNA sequencing and immunohistochemistry analyses of clinical gingival epithelia revealed dysregulation in the lysosome pathway characterized by reduced levels of lysosome-associated membrane glycoprotein 2 (LAMP2) and V-type proton ATPase 16 kDa proteolipid subunit c (ATP6V0C) in subjects with DP. In vitro stimulation of human gingival epithelial cells (HGECs) with a hyperglycemic microenvironment showed elevated release of proinflammatory cytokines, compromised lysosomal acidity and blocked autophagy. Moreover, HGECs with deficiency in ATP6V0C demonstrated impaired autophagy and heightened inflammatory response, mirroring the effects of high glucose stimulation. Proteomic analysis of acetylation modifications identified altered acetylation levels in 28 autophagy-lysosome pathway-related proteins and 37 sites in HGECs subjected to high glucose stimulation or siATP6V0C. Overall, our finding highlights the pivotal role of lysosome impairment in autophagy obstruction in DP and suggests a potential impact of altered acetylation of relevant proteins on the interplay between lysosome dysfunction and autophagy blockage. These insights may pave the way for the development of effective therapeutic strategies against DP.

Restore Intestinal Barrier Integrity: An Approach for Inflammatory Bowel Disease Therapy

The intestinal barrier maintained by various types of columnar epithelial cells, plays a crucial role in regulating the interactions between the intestinal contents (such as the intestinal microbiota), the immune system, and other components. Dysfunction of the intestinal mucosa is a significant pathophysiological mechanism and clinical manifestation of inflammatory bowel disease (IBD). However, current therapies for IBD primarily focus on suppressing inflammation, and no disease-modifying treatments specifically target the epithelial barrier. Given the side effects associated with chronic immunotherapy, effective alternative therapies that promote mucosal healing are highly attractive. In this review, we examined the function of intestinal epithelial barrier function and the mechanisms of behind its disruption in IBD. We illustrated the complex process of intestinal mucosal healing and proposed therapeutic approaches to promote mucosal healing strategies in IBD. These included the application of stem cell transplantation and organ-like tissue engineering approaches to generate new intestinal tissue. Finally, we discussed potential strategies to restore the function of the intestinal barrier as a treatment for IBD.

Loss of monopolar spindle-binding protein 3B expression promotes colorectal cancer invasiveness by activation of target of rapamycin kinase/autophagy signaling

BACKGROUND

Monopolar spindle-binding protein 3B (MOB3B) functions as a signal transducer and altered MOB3B expression is associated with the development of human cancers.

AIM

To investigate the role of MOB3B in colorectal cancer (CRC).

METHODS

This study collected 102 CRC tissue samples for immunohistochemical detection of MOB3B expression for association with CRC prognosis. After overexpression and knockdown of MOB3B expression were induced in CRC cell lines, changes in cell viability, migration, invasion, and gene expression were assayed. Tumor cell autophagy was detected using transmission electron microscopy, while nude mouse xenograft experiments were performed to confirm the in-vitro results.

RESULTS

MOB3B expression was reduced in CRC vs normal tissues and loss of MOB3B expression was associated with poor CRC prognosis. Overexpression of MOB3B protein in vitro attenuated the cell viability as well as the migration and invasion capacities of CRC cells, whereas knockdown of MOB3B expression had the opposite effects in CRC cells. At the molecular level, microtubule-associated protein light chain 3 II/I expression was elevated, whereas the expression of matrix metalloproteinase (MMP)2, MMP9, sequestosome 1, and phosphorylated mechanistic target of rapamycin kinase (mTOR) was downregulated in MOB3B-overexpressing RKO cells. In contrast, the opposite results were observed in tumor cells with MOB3B knockdown. The nude mouse data confirmed these in-vitro findings, i.e., MOB3B expression suppressed CRC cell xenograft growth, whereas knockdown of MOB3B expression promoted the growth of CRC cell xenografts.

CONCLUSION

Loss of MOB3B expression promotes CRC development and malignant behaviors, suggesting a potential tumor suppressive role of MOB3B in CRC by inhibition of mTOR/autophagy signaling.

Epigenetic regulation of autophagy by non-coding RNAs and exosomal non-coding RNAs in colorectal cancer: A narrative review

One of the major diseases affecting people globally is colorectal cancer (CRC), which is primarily caused by a lack of effective medical treatment and a limited understanding of its underlying mechanisms. Cellular autophagy functions to break down and eliminate superfluous proteins and substances, thereby facilitating the continual replacement of cellular elements and generating vital energy for cell processes. Non-coding RNAs and exosomal ncRNAs have a crucial impact on regulating gene expression and essential cellular functions such as autophagy, metastasis, and treatment resistance. The latest research has indicated that specific ncRNAs and exosomal ncRNA to influence the process of autophagy in CRC cells, which could have significant consequences for the advancement and treatment of this disease. It has been determined that a variety of ncRNAs have a vital function in regulating the genes essential for the formation and maturation of autophagosomes. Furthermore, it has been confirmed that ncRNAs have a considerable influence on the signaling pathways associated with autophagy, such as those involving AMPK, AKT, and mTOR. Additionally, numerous ncRNAs have the potential to affect specific genes involved in autophagy. This study delves into the control mechanisms of ncRNAs and exosomal ncRNAs and examines how they simultaneously influence autophagy in CRC.

Timosaponin BⅡ reduces colonic inflammation and alleviates DSS-induced ulcerative colitis by inhibiting NLRP3

ETHNOPHARMACOLOGICAL RELEVANCE

The Timosaponin BⅡ (TBⅡ) is one of the main active components of the traditional Chinese medicine Anemarrhena asphodeloides, and it is a steroidal saponin with various pharmacological activities such as anti-oxidation, anti-inflammatory and anti-apoptosis. However, its role in acute ulcerative colitis remains unexplored thus far.

AIM OF THE STUDY

This study aims to investigate the protective effect of TBⅡ against dextran sulfate sodium (DSS)-induced ulcerative colitis in mice and elucidate its underlying mechanisms.

METHODS

Wild-type (WT) and NLRP3 knockout (NLRP3-/-) mice were applied to evaluate the protective effect of TBⅡ in DSS-induced mice colitis. Pharmacological inhibition of NLRP3 or adenovirus-mediated NLRP3 overexpression in bone marrow-derived macrophages (BMDM) from WT mice and colonic epithelial HCoEpiC cells was used to assess the role of TBⅡ in LPS + ATP-induced cell model. RNA-seq, ELISA, western blots, immunofluorescence staining, and expression analysis by qPCR were performed to examine the alterations of colonic NLRP3 expression in DSS-induced colon tissues and LPS + ATP-induced cells, respectively.

RESULTS

In mice with DSS-induced ulcerative colitis, TBⅡ treatment attenuated clinical symptoms, repaired the intestinal mucosal barrier, reduced inflammatory infiltration, and alleviated colonic inflammation. RNA-seq analysis and protein expression levels demonstrated that TBⅡ could prominently inhibit NLRP3 signaling. TBⅡ-mediated NLRP3 inhibition was associated with alleviating intestinal permeability and inflammatory response via the blockage of communication between epithelial cells and macrophages, probably in an NLRP3 inhibition mechanism. However, pharmacological inhibition of NLRP3 by MCC950 or Ad-NLRP3 mediated NLRP3 overexpression significantly impaired the TBⅡ-mediated anti-inflammatory effect. Mechanistically, TBⅡ-mediated NLRP3 inhibition may be partly associated with the suppression of NF-κB, a master pro-inflammatory factor for transcriptional regulation of NLRP3 expression in the priming step. Moreover, co-treatment TBⅡ with NF-κB inhibitor BAY11-7082 partly impaired TBⅡ-mediated NLRP3 inhibition, and consequently affected the IL-1β mature and secretion. Importantly, TBⅡ-mediated amelioration was not further enhanced in NLPR3-/- mice.

CONCLUSION

TBⅡ exerted a prominent protective effect against DSS-induced colitis via regulation of alleviation of intestinal permeability and inflammatory response via the blockage of crosstalk between epithelial cells and macrophages in an NLRP3-mediated inhibitory mechanism. These beneficial effects could make TBⅡ a promising drug for relieving colitis.

AMBRA1 promotes intestinal inflammation by antagonizing PP4R1/PP4c mediated IKK dephosphorylation in an autophagy-independent manner

IκB kinase (IKK) complex is central regulators of the NF-κB pathway, and dysregulation of IKK phosphorylation leads to hyperactivation of proinflammatory response in various chronic inflammatory diseases, including inflammatory bowel disease (IBD). However, the dynamic modulation of IKK phosphorylation and dephosphorylation in intestinal inflammation remains uncharacterized. Here, we found that autophagy/beclin-1 regulator 1 (AMBRA1) was highly expressed in inflamed colons in a colitis mouse model and in clinical IBD samples. Importantly, AMBRA1 deletion significantly decreased proinflammatory cytokine expression and enhanced the therapeutic effect of infliximab on intestinal inflammation. Mechanistically, the N-term F1 domain of AMBRA1 was required for AMBRA1 to competitively interact with protein phosphatase 4 regulatory subunit 1 (PP4R1) and catalytic protein phosphatase 4 (PP4c) to suppress their interactions with IKK, promote the dissociation of the PP4R1/PP4c complex, and antagonize the dephosphorylation activity of this complex towards the IKK complex. In response to TNF-α stimulation, IKKα phosphorylates AMBRA1 at S1043 to stabilize AMBRA1 expression by impairing its binding to Cullin4A (CUL4A) to decrease its CUL4A-mediated K48-linked ubiquitination. Overall, our study identifies an autophagy-independent function of AMBRA1 as a positive modulator of IKK phosphorylation to promote intestinal inflammation, thus providing a new targeted therapeutic strategy for patients with refractory IBD.

Plant-derived vesicle-like nanoparticles: A new tool for inflammatory bowel disease and colitis-associated cancer treatment

Long-term use of conventional drugs to treat inflammatory bowel diseases (IBD) and colitis-associated cancer (CAC) has an adverse impact on the human immune system and easily leads to drug resistance, highlighting the urgent need to develop novel biotherapeutic tools with improved activity and limited side effects. Numerous products derived from plant sources have been shown to exert antibacterial, anti-inflammatory and antioxidative stress effects. Plant-derived vesicle-like nanoparticles (PDVLNs) are natural nanocarriers containing lipids, protein, DNA and microRNA (miRNA) with the ability to enter mammalian cells and regulate cellular activity. PDVLNs have significant potential in immunomodulation of macrophages, along with regulation of intestinal microorganisms and friendly antioxidant activity, as well as overcoming drug resistance. PDVLNs have utility as effective drug carriers and potential modification, with improved drug stability. Since immune function, intestinal microorganisms, and antioxidative stress are commonly targeted key phenomena in the treatment of IBD and CAC, PDVLNs offer a novel therapeutic tool. This review provides a summary of the latest advances in research on the sources and extraction methods, applications and mechanisms in IBD and CAC therapy, overcoming drug resistance, safety, stability, and clinical application of PDVLNs. Furthermore, the challenges and prospects of PDVLN-based treatment of IBD and CAC are systematically discussed.

Border Control: The Role of the Microbiome in Regulating Epithelial Barrier Function

The gut mucosal epithelium is one of the largest organs in the body and plays a critical role in regulating the crosstalk between the resident microbiome and the host. To this effect, the tight control of what is permitted through this barrier is of high importance. There should be restricted passage of harmful microorganisms and antigens while at the same time allowing the absorption of nutrients and water. An increased gut permeability, or "leaky gut", has been associated with a variety of diseases ranging from infections, metabolic diseases, and inflammatory and autoimmune diseases to neurological conditions. Several factors can affect gut permeability, including cytokines, dietary components, and the gut microbiome. Here, we discuss how the gut microbiome impacts the permeability of the gut epithelial barrier and how this can be harnessed for therapeutic purposes.

Injectable hydrogels as promising in situ therapeutic platform for cartilage tissue engineering

Injectable hydrogels are gaining prominence as a biocompatible, minimally invasive, and adaptable platform for cartilage tissue engineering. Commencing with their synthesis, this review accentuates the tailored matrix formulations and cross-linking techniques essential for fostering three-dimensional cell culture and melding with complex tissue structures. Subsequently, it spotlights the hydrogels' enhanced properties, highlighting their augmented functionalities and broadened scope in cartilage tissue repair applications. Furthermore, future perspectives are advocated, urging continuous innovation and exploration to surmount existing challenges and harness the full clinical potential of hydrogels in regenerative medicine. Such advancements are crucial for validating the long-term efficacy and safety of hydrogels, positioning them as a promising direction in regenerative medicine to address cartilage-related ailments.

Autophagy in colitis-associated colon cancer: exploring its potential role in reducing initiation and preventing IBD-Related CAC development

ABBREVIATIONS

A. muciniphila: Akkermansia muciniphila; AIEC: adherent invasive Escherichia coli; AOM/DSS: azoxymethane-dextran sodium sulfate; ATG: autophagy related; BECN1: beclin1, autophagy related; CAC: colitis-associated colon cancer; CCDC50: coiled-coil domain containing 50; CLDN2: claudin 2; CoPEC: colibactin-producing Escherichia coli; CRC: colorectal cancer; DAMPs: danger/damage-associated molecular patterns; DC: dendritic cell; DSS: dextran sulfate sodium; DTP: drug-resistant persistent; ER: endoplasmic reticulum; ERN1/IRE1α: endoplasmic reticulum to nucleus signaling 1; IBD: inflammatory bowel disease; IECs: intestinal epithelial cells; IKK: IkappaB kinase; IL: interleukin; IRGM1: immunity-related GTPase family M member 1; ISC: intestinal stem cell; LPS: lipopolysaccharide; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MAPK: mitogen-activated protein kinase; MDP: muramyl dipeptide; MELK: maternal embryonic leucine zipper kinase; MHC: major histocompatibility complex; miRNA: microRNA; MTOR: mechanistic target of rapamycin kinase; NLRP3: NLR family, pyrin domain containing 3; NOD2: nucleotide-binding oligomerization domain containing 2; NRBF2: nuclear receptor binding factor 2; PAMPs: pathogen-associated molecular patterns; PI3K: class I phosphoinositide 3-kinase; PtdIns3K: class III phosphatidylinositol 3-kinase; PYCARD/ASC: PYD and CARD domain containing; RALGAPA2/RalGAPα2: Ral GTPase activating protein protein, alpha subunit 2 (catalytic); RIPK2/CARD3: receptor (TNFRSF)-interacting serine-threonine kinase 2; RIPK3: receptor-interacting serine-threonine kinase 3; ROS: reactive oxygen species; sCRC: sporadic colorectal cancer; SMARCA4/BRG1: SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4; SQSTM1: sequestosome 1; STAT3: signal transducer and activator of transcription 3; TNF/TNFA: tumor necrosis factor; ULK1: unc-51 like autophagy activating kinase 1; UPR: unfolded protein response; WT: wild-type.

BRG1 enhances porcine iPSC pluripotency through WNT/β-catenin and autophagy pathways

Brahma-related gene 1 (BRG1) enhances the pluripotency of embryonic and adult stem cells, however, its effect on induced pluripotent stem cell (iPSC) pluripotency has not been reported. The aim of this study was to investigate the effect of BRG1 on porcine iPSC pluripotency and its mechanisms. The effect of BRG1 on porcine iPSC pluripotency was explored by positive and negative control it. The mechanism was investigated by regulating the WNT/β-catenin signaling pathway and autophagy flux. The results showed that inhibition of BRG1 decreased pluripotency-related gene expression in porcine iPSCs; while its overexpression had the opposite effect, the expression of WNT/β-catenin signaling pathway- and autophagy-related genes was significantly up-regulated (P < 0.05) in the BRG1 overexpressed group when compared to the control group. Inhibited pluripotency-related gene or protein expression, decreased autophagy flux, and increased mitochondrial length and mitochondrial membrane potential (MMP) were observed when porcine iPSCs were treated with the WNT/β-catenin signaling pathway inhibitor IWR-1. Forced BRG1 expression restored porcine iPSC pluripotency, increased autophagy flux, shortened mitochondria, and reduced MMP. Lastly, Compound C was used to activate porcine iPSC autophagy, and it was found that the expression of BRG1 and β-catenin increased, and pluripotency-related gene and protein expression was up-regulated; these effects were reversed when the BRG1 inhibitor PFI-3 and IWR-1 were added. These results suggested that BRG1 enhanced the pluripotency of porcine iPSCs through WNT/β-catenin and autophagy pathways.

An Engineered Butyrate-Derived Polymer Nanoplatform as a Mucosa-Healing Enhancer Potentiates the Therapeutic Effect of Magnolol in Inflammatory Bowel Disease

Colonic epithelial damage and dysregulated immune response are crucial factors in the progression and exacerbation of inflammatory bowel disease (IBD). Nanoenabled targeted drug delivery to the inflamed intestinal mucosa has shown promise in inducing and maintaining colitis remission, while minimizing side effects. Inspired by the excellent antioxidative and anti-inflammatory efficacy of naturally derived magnolol (Mag) and gut homeostasis regulation of microbiota-derived butyrate, we developed a pH/redox dual-responsive butyrate-rich polymer nanoparticle (PSBA) as an oral Mag delivery system for combinational therapy of IBD. PSBA showed a high butyrate content of 22% and effectively encapsulated Mag. The Mag-loaded nanoparticles (PSBA@Mag) demonstrated colonic pH and reduction-responsive drug release, ensuring efficient retention and adhesion in the colon of colitis mice. PSBA@Mag not only normalized the level of reactive oxygen species and inflammatory effectors in inflamed colonic mucosa but also restored the epithelial barrier function in both ulcerative colitis and Crohn's disease mouse models. Importantly, PSBA promoted the migration and healing ability of intestinal epithelial cells in vitro and in vivo, sensitizing the therapeutic efficacy of Mag in animal models. Moreover, transcriptomics and metabolism analyses revealed that PSBA@Mag mitigated inflammation by suppressing the production of pro-inflammatory cytokines and chemokines and restoring the lipid metabolism. Additionally, this nanomedicine modulated the gut microbiota by inhibiting pathogenic Proteus and Escherichia-Shigella and promoting the proliferation of beneficial probiotics, including Lachnoclostridium, Lachnospiraceae_NK4A136_group and norank_f_Ruminococcaceae. Overall, our findings highlight the potential of butyrate-functionalized polymethacrylates as versatile and effective nanoplatforms for colonic drug delivery and mucosa repair in combating IBD and other gastrointestinal disorders.

Targeting the chromatin remodeling protein BRG1 in liver fibrosis: Mechanism and translational potential

AIMS

Liver fibrosis is characterized by excessive deposition of extracellular matrix (ECM) proteins in the interstitia. Hepatic stellate cells (HSCs) are considered the major source for ECM-producing myofibroblasts contributing to liver fibrosis. The molecular mechanism whereby HSC-myofibroblast transition is regulated remains incompletely understood. We investigated the involvement of BRG1, a chromatin remodeling protein, in this process.

METHODS

Rosa26-Smarca4 mice were crossed to Lrat-Cre mice to generate HSC-specific BRG1 transgenic mice. Liver fibrosis was induced by bile duct ligation (BDL) or injection with carbon tetrachloride (CCl4).

RESULTS

We report here that over-expression of BRG1 promoted HSC-myofibroblast transition in vitro. More importantly, the BRG1 transgenic mice displayed amplification of liver fibrogenesis, induced by BDL or CCl4 injection, compared to the wild type littermates. On the contrary, BRG1 inhibition by a small-molecule compound (PFI-3) attenuated HSC-myofibroblast transition in vitro and ameliorated liver fibrosis in a dose-dependent manner in mice. RNA-seq analysis showed that PFI-3 treatment preferentially influenced the expression of ECM genes in activated HSCs.

CONCLUSION

Our data provide strong evidence that BRG1 plays an important role in HSC-myofibroblast transition and suggest that targeting BRG1 could be considered as a reasonable strategy for the intervention of liver fibrosis.

Smarca2 genetic ablation is phenotypically benign in a safety assessment of tamoxifen-inducible conditional knockout rats

SMARCA2 and SMARCA4 are the ATPases of the SWI/SNF chromatin remodeling complex, which play a significant role in regulating transcriptional activity and DNA repair in cells. SMARCA2 has become an appealing synthetic-lethal, therapeutic target in oncology, as mutational loss of SMARCA4 in many cancers leads to a functional dependency on residual SMARCA2 activity. Thus, for therapeutic development, an important step is understanding any potential safety target-associated liabilities of SMARCA2 inhibition. To best mimic a SMARCA2 therapeutic, a tamoxifen-inducible (TAMi) conditional knockout (cKO) rat was developed using CRISPR technology to understand the safety profile of Smarca2 genetic ablation in a model system that avoids potential juvenile and developmental phenotypes. As the rat is the prototypical rodent species utilized in toxicology studies, a comprehensive toxicological and pathological assessment was conducted in both heterozygote and homozygous knockout rats at timepoints up to 28 days, alongside relevant corresponding controls. To our knowledge, this represents the first TAMi cKO rat model utilized for safety assessment evaluations. No significant target-associated phenotypes were observed when Smarca2 was ablated in mature (11- to 15-week-old) rats; however subsequent induction of SMARCA4 was evident that could indicate potential compensatory activity. Similar to mouse models, rat CreERT2-transgene and TAMi toxicities were characterized to avoid confounding study interpretation. In summary, a lack of significant safety findings in Smarca2 cKO rats highlights the potential for therapeutics targeting selective SMARCA2 ATPase activity; such therapies are predicted to be tolerated in patients without eliciting significant on-target toxicities.

BRG1 mediates protective ability of spermidine to ameliorate osteoarthritic cartilage by Nrf2/KEAP1 and STAT3 signaling pathway

BACKGROUND

Spermidine (SPD) is a natural polyamine that shows beneficial effects on osteoarthritis (OA). However, the effect of SPD on cartilage inflammation remains unknown. This study aimed to investigate the potential mechanisms underlying the protective effect of SPD against OA-induced articular cartilage degradation.

METHOD

SW1353 human chondrocytes were treated with hydrogen peroxide and lipopolysaccharide to induce models of inflammation and oxidative stress, followed by different dose of SPD intervention. Moreover, mice that underwent anterior cruciate ligament transection were bred and treated with SPD. The effects of SPD were observed using a CCK-8 kit, real-time polymerase chain reaction, immunoblotting, and immunofluorescent assays.

RESULT

SPD significantly increased the expression of antioxidant proteins, chondrogenic genes, and inflammatory factors both in vivo and in vitro. And injury of the mouse cartilage was also reduced by SPD. Moreover, SPD activated the Nrf2/KEAP1 pathway and inhibited STAT3 phosphorylation. BRG1 expression was decreased in osteoarthritic mouse cartilage, whereas SPD treatment caused an upregulation. However, when BRG1 was specifically inhibited by an adeno-associated virus and small interfering RNA, the antioxidant and anti-inflammatory effects of SPD were significantly diminished both in vitro and in vivo.

CONCLUSION

We found that SPD ameliorated cartilage damage in OA by activating the BRG1-mediated Nrf2/KEAP1 pathway. SPD and BRG1 may provide new therapeutic options or targets for the treatment of OA.

Autotaxin promotes the degradation of the mucus layer by inhibiting autophagy in mouse colitis

Autotaxin (ATX or ENPP2) is an autocrine enzyme associated with the metabolism of various phospholipids. ATX has recently been identified as a regulatory factor in immune-related and inflammation-associated diseases, such as inflammatory bowel disease, but the exact mechanism is unclear. Here, we treated mice with recombinant ATX protein or an ATX inhibitor to investigate the effect of ATX on colitis in mice and the underlying mechanism. In a mouse model of colitis, ATX expression was increased, autophagy was impaired, and the mucus barrier was disrupted. Recombinant ATX protein promoted intestinal inflammation, inhibited autophagy, and disrupted the mucus barrier, while an ATX inhibitor had the opposite effect. Next, we treated mice that received ATX with an autophagy activator and an adenosine 5'-monophosphate-activated protein kinase (AMPK) agonist. We observed that autophagy activator and AMPK agonist could repair the mucus barrier and alleviate intestinal inflammation in ATX-treated mice. In vitro, we obtained consistent results. Thus, we concluded that ATX could inhibit autophagy through the AMPK pathway, which consequently disordered the mucus barrier and aggravated intestinal inflammation.

Emerging role of autophagy in colorectal cancer: Progress and prospects for clinical intervention

Autophagy is a physiological mechanism in which cells degrade themselves and quickly recover the degraded cell components. Recent studies have shown that autophagy plays an important role in the occurrence, development, treatment, and prognosis of colorectal cancer. In the early stages of colorectal cancer, autophagy can inhibit the production and development of tumors through multiple mechanisms such as maintaining DNA stability, inducing tumor death, and enhancing immune surveillance. However, as colorectal cancer progresses, autophagy may mediate tumor resistance, enhance tumor metabolism, and other pathways to promote tumor development. Therefore, intervening in autophagy at the appropriate time has broad clinical application prospects. This article summarizes the recent research progress of autophagy and colorectal cancer and is expected to provide new theoretical basis and reference for clinical treatment of colorectal cancer.

Vitamin D protects intestines from liver cirrhosis-induced inflammation and oxidative stress by inhibiting the TLR4/MyD88/NF-κB signaling pathway

Liver cirrhosis affects the structures and physiological functions of the intestine. Our previous study revealed that liver injury inhibited 25-hydroxylation of vitamin D (25(OH)-VD). The aim of this study was to investigate the roles and mechanisms of vitamin D in liver cirrhosis-induced intestinal injury. The rat liver cirrhosis model was established through the administration of carbon tetrachloride (CCl₄) for 8 weeks. Hematoxylin-eosin staining was performed to unveil the intestinal injury induced by liver cirrhosis. Enzyme-linked immunosorbent and reverse transcription PCR (RT-PCR) analysis were used to determine the levels of 25(OH)-VD, vitamin D receptor, Cytochrome P450 24A1 (CYP24A1), and α-defensin 5 (DEFA5) in rat and human serum of liver cirrhosis. Furthermore, liver cirrhosis rats were treated with low-dose (500 IU/kg) and high-dose (2,000 IU/kg) vitamin D intraperitoneally. The expression levels of TLR4/MyD88/NF-κB signaling pathway were evaluated by RT-PCR and Western blot. In conclusion, we determined the deficiency of vitamin D and down-regulation of DEFA5 and intestinal damage induced by liver cirrhosis. Moreover, vitamin D effectively inhibited liver cirrhosis-induced intestinal inflammation and oxidative stress through the TLR4/MyD88/NF-κB pathway. Vitamin D might be a promising therapeutic strategy for future treatment of liver-induced intestinal injury.

BRG1 is involved in vascular calcification in chronic renal disease via autophagy of vascular smooth muscle cells

We aimed to investigate the mechanisms of Brahma related gene 1 (BRG1) in promoting vascular calcification in chronic kidney disease (CKD). The expression of BRG1 was examined in high phosphorus stimulated rat aortic smooth muscle cells (RASMCs) and calcified artery tissues from rat models and hemodialysis patients. Autophagosome formation was measured in high phosphorus stimulated RASMCs with and without BRG1 knock-down. We also detected the coexistence of BGR1 and exosomes, and measured the circulatory levels of BRG1 in the hemodialysis patients. BRG1 promoted the osteogenic transdifferentiation of RASMCs. Silencing BRG1 prevented autophagy from being induced by high phosphorus stimulation in RASMCs. Increased expression of BRG1 was observed in calcified blood vessels. Serum BRG1 level increased in the hemodialysis patients. BRG1 was involved in the development of high phosphorus induced osteogenic phenotype in vitro and in vivo, and its underlying mechanism might be facilitating autophagy.

The SMARCA4R1157W mutation facilitates chromatin remodeling and confers PRMT1/SMARCA4 inhibitors sensitivity in colorectal cancer

Genomic studies have demonstrated a high frequency of genetic alterations in components of the SWI/SNF complex including the core subunit SMARCA4. However, the mechanisms of tumorigenesis driven by SMARCA4 mutations, particularly in colorectal cancer (CRC), remain largely unknown. In this study, we identified a specific, hotspot mutation in SMARCA4 (c. 3721C>T) which results in a conversion from arginine to tryptophan at residue 1157 (R1157W) in human CRC tissues associated with higher-grade tumors and controls CRC progression. Mechanistically, we found that the SMARCA4^R1157W mutation facilitated its recruitment to PRMT1-mediated H4R3me2a (asymmetric dimethylation of Arg 3 in histone H4) and enhanced the ATPase activity of SWI/SNF complex to remodel chromatin in CRC cells. We further showed that the SMARCA4^R1157W mutant reinforced the transcriptional expression of EGFR and TNS4 to promote the proliferation of CRC cells and patient-derived tumor organoids. Importantly, we demonstrated that SMARCA4^R1157W CRC cells and mutant cell-derived xenografts were more sensitive to the combined inhibition of PRMT1 and SMARCA4 which act synergistically to suppress cell proliferation. Together, our findings show that SMARCA4-R1157W is a critical activating mutation, which accelerates CRC progression through facilitating chromatin recruitment and remodeling. Our results suggest a potential precision therapeutic strategy for the treatment of CRC patients carrying the SMARCA4^R1157W mutation.

Targetable Brg1-CXCL14 axis contributes to alcoholic liver injury by driving neutrophil trafficking

Alcoholic liver disease (ALD) accounts for a large fraction of patients with cirrhosis and hepatocellular carcinoma. In the present study we investigated the involvement of Brahma-related gene 1 (Brg1) in ALD pathogenesis and implication in ALD intervention. We report that Brg1 expression was elevated in mouse models of ALD, in hepatocyte exposed to alcohol, and in human ALD specimens. Manipulation of Brg1 expression in hepatocytes influenced the development of ALD in mice. Flow cytometry showed that Brg1 deficiency specifically attenuated hepatic infiltration of Ly6G⁺ neutrophils in the ALD mice. RNA-seq identified C-X-C motif chemokine ligand 14 (CXCL14) as a potential target for Brg1. CXCL14 knockdown alleviated whereas CXCL14 over-expression enhanced ALD pathogenesis in mice. Importantly, pharmaceutical inhibition of Brg1 with a small-molecule compound PFI-3 or administration of an antagonist to the CXCL14 receptor ameliorated ALD pathogenesis in mice. Finally, a positive correlation between Brg1 expression, CXCL14 expression, and neutrophil infiltration was detected in ALD patients. In conclusion, our data provide proof-of-concept for targeting the Brg1-CXCL14 axis in ALD intervention.

BRG1: Promoter or Suppressor of Cancer? The Outcome of BRG1's Interaction with Specific Cellular Pathways

BRG1 is one of two catalytic subunits of the SWI/SNF ATP-dependent chromatin-remodeling complex. In cancer, it has been hypothesized that BRG1 acts as a tumor suppressor. Further study has shown that, under certain circumstances, BRG1 acts as an oncogene. Targeted knockout of BRG1 has proven successful in most cancers in suppressing tumor growth and proliferation. Furthermore, BRG1 effects cancer proliferation in oncogenic KRAS mutated cancers, with varying directionality. Thus, dissecting BRG1's interaction with various cellular pathways can highlight possible intermediates that can facilitate the design of different treatment methods, including BRG1 inhibition. Autophagy and apoptosis are two important cellular responses to stress. BRG1 plays a direct role in autophagy and apoptosis and likely promotes autophagy and suppresses apoptosis, supporting unfettered cancer growth. PRMT5 inhibits transcription by interacting with ATP-dependent chromatin remodeling complexes, such as SWI/SNF. When PRMT5 associates with the SWI/SNF complex, including BRG1, it represses tumor suppressor genes. The Ras/Raf/MAPK/ERK1/2 pathway in cancers is a signal transduction pathway involved in the transcription of genes related to cancer survival. BRG1 has been shown to effect KRAS-driven cancer growth. BRG1 associates with several proteins within the signal transduction pathway. In this review, we analyze BRG1 as a promising target for cancer inhibition and possible synergy with other cancer treatments.

Suppression of microRNA-222-3p ameliorates ulcerative colitis and colitis-associated colorectal cancer to protect against oxidative stress via targeting BRG1 to activate Nrf2/HO-1 signaling pathway

Oxidative stress is an important pathogenic factor in ulcerative colitis (UC) and colitis-associated colorectal cancer (CAC), further impairing the entire colon. Intestinal epithelial cells (IECs) are crucial components of innate immunity and play an important role in maintaining intestinal barrier function. Recent studies have indicated that microRNA-222-3p (miR-222-3p) is increased in colon of UC and colorectal cancer (CRC) patients, and miR-222-3p is a crucial regulator of oxidative stress. However, whether miR-222-3p influences IEC oxidative stress in UC and CAC remains unknown. This study investigated the effect of miR-222-3p on the regulation of IEC oxidative stress in UC and CAC. An in vitro inflammation model was established in NCM460 colonic cells, mouse UC and CAC models were established in vivo, and IECs were isolated. The biological role and mechanism of miR-222-3p-mediated oxidative stress in UC and CAC were determined. We demonstrated that miR-222-3p expression was notably increased in dextran sulfate sodium (DSS)-induced NCM460 cells and IECs from UC and CAC mice. In vitro, these results showed that the downregulation of miR-222-3p reduced oxidative stress, caspase-3 activity, IL-1β and TNF-α in DSS-induced NCM460 cells. We further identified BRG1 as the target gene of miR-222-3p, and downregulating miR-222-3p alleviated DSS-induced oxidative injury via promoting BRG1-mediated activation Nrf2/HO-1 signaling in NCM460 cells. The in vivo results demonstrated that inhibiting miR-222-3p in IECs significantly relieved oxidative stress and inflammation in the damaged colons of UC and CAC mice, as evidenced by decreases in ROS, MDA, IL-1β and TNF-α levels and increases in GSH-Px levels. Our study further demonstrated that inhibiting miR-222-3p in IECs attenuated oxidative damage by targeting BRG1 to activate the Nrf2/HO-1 signaling. In summary, inhibiting miR-222-3p in IECs attenuates oxidative stress by targeting BRG1 to activate the Nrf2/HO-1 signaling, thereby reducing colonic inflammation and tumorigenesis.

Polysaccharides from natural Cordyceps sinensis attenuated dextran sodium sulfate-induced colitis in C57BL/6J mice

As potential candidates for treating ulcerative colitis (UC), polysaccharides have been attracting extensive interest in recent years. Cordyceps sinensis (C. sinensis) is a kind of traditional Chinese edible food, and its polysaccharide fractions have been found to be effective in regulating immunity and protecting the kidneys. To determine the potential function of polysaccharides from natural C. sinensis on UC, their effects in terms of histological, serological, biochemical, and immunological aspects on dextran sulphate sodium (DSS)-induced colitis mice model were investigated. Results showed that the polysaccharides significantly alleviated colitis by increasing the colon length, alleviating colon tissue damage, and inhibiting the activation of the NF-κB pathway. In addition, polysaccharides reduced the contents of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the serum, increased the number of goblet cells, and improved the expression of intestinal tight junction proteins (Occludin and Claudin-1). They also evidently enhanced the formation of IgA-secretory cells and sIgA contents. Furthermore, the polysaccharides modulated the gut microbiota by decreasing the relative abundance of Bilophila and increasing the relative abundance of Dehalobacterium, Coprococcus, Oscillospira, and Desulfovibrio, which is accompanied by an increase in the short chain fatty acids' (SCFAs) concentrations in cecal contents. These results suggested that C. sinensis polysaccharides possessed promising intervening effects on experimental acute UC in mice.

WIPI2 enhances the vulnerability of colorectal cancer cells to erastin via bioinformatics analysis and experimental verification

Introduction

WD Repeat Domain Phosphoinositide Interacting 2 (WIPI2) is a WD repeat protein that interacts with phosphatidylinositol and regulates multiprotein complexes by providing a b-propeller platform for synchronous and reversible protein-protein interactions assembled proteins. Ferroptosis is a novel iron-dependent form of cell death. It is usually accompanied with the accumulation of membrane lipid peroxides. Our study is to focus on investigating the effect of WIPI2 on the growth and ferroptosis of colorectal cancer (CRC) cells and its potential mechanism.

Methods

We analyzed the expression of WIPI2 in colorectal cancer versus normal tissues through The Cancer Genome Atlas (TCGA), and the relationship between clinical traits and WIPI2 expression and prognosis was assessed by univariate and multifactorial cox analysis. Next, we constructed the siRNAs targeting the WIPI2 sequence si-WIPI2 to further investigate the mechanism of WIPI2 in CRC cells through vitro experiments.

Results

Public data from the TCGA platform showed that WIPI2 expression was significantly elevated in colorectal cancer tissues compared to paracancerous tissues, and high WIPI2 expressionpredicted poor prognosis for CRC patients. Moreover, we found that the knockdown of WIPI2 expression could inhibit the growth and proliferation of HCT116 and HT29 cells. Furthermore, we found that the expression level of ACSL4 decreased and that of GPX4 increased when WIPI2 was knocked down, suggesting that WIPI2 can potentially positively regulate CRC ferroptosis. Meanwhile, both NC and si groups were able to further inhibit cell growth activity, as well as increase WIPI2 and decrease GPX4 expression when treated with Erastin, but the rate of cell viability inhibition and the trend of protein changes were more significantly in the NC group than si groups, which indicated that Erastin induced CRC ferroptosis through the WIPI2/GPX4 pathway thereby enhancing the sensitivity of colorectal cancer cells to Erastin.

Conclusions

Our study suggested that WIPI2 had a promotional effect on the growth of colorectal cancer cells, and it also played an important role in the ferroptosis pathway.

MoSnf5 Regulates Fungal Virulence, Growth, and Conidiation in Magnaporthe oryzae

Snf5 (sucrose nonfermenting) is a core component of the SWI/SNF complexes and regulates diverse cellular processes in model eukaryotes. In plant pathogenic fungi, its biological function and underlying mechanisms remain unexplored. In this study, we investigated the biological roles of MoSnf5 in plant infection and fungal development in the rice blast pathogen Magnaporthe oryzae. The gene deletion mutants of MoSNF5 exhibited slower vegetative hyphal growth, severe defects in conidiogenesis, and impaired virulence and galactose utilization capacities. Domain dissection assays showed that the Snf5 domain and the N- and C-termini of MoSnf5 were all required for its full functions. Co-immunoprecipitation and yeast two-hybrid assays showed that MoSnf5 physically interacts with four proteins, including a transcription initiation factor MoTaf14. Interestingly, the ∆MoTaf14 mutants showed similar phenotypes as the ∆Mosnf5 mutants on fungal virulence and development. Moreover, assays on GFP-MoAtg8 expression and localization showed that both the ∆Mosnf5 and ∆MoTaf14 mutants were defective in autophagy. Taken together, MoSnf5 regulates fungal virulence, growth, and conidiation, possibly through regulating galactose utilization and autophagy in M. oryzae.

Delineation of a SMARCA4-specific competing endogenous RNA network and its function in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a common malignancy worldwide, and the mortality rate continues to rise each year. SMARCA4 expression has been associated with poor prognosis in various types of cancer; however, the specific mechanism of action of SMARCA4 in HCC needs to be fully elucidated.

AIM

To explore the specific mechanism of action of SMARCA4 in HCC.

METHODS

Herein, the expression level of SMARCA4 as well as its association with HCC prognosis were evaluated using transcriptome profiling and clinical data of 18 different types of cancer collected from The Cancer Genome Atlas database. Furthermore, SMARCA4-high and -low groups were identified. Thereafter, gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to identify the function of SMARCA4, followed by construction of a SMARCA4-specific competing endogenous RNA (ceRNA) network using starBase database. The role of SMARCA4 in immunotherapy and its association with immune cells were assessed using correlation analysis.

RESULTS

It was observed that SMARCA4 was overexpressed and negatively correlated with prognosis in HCC. Further, SMARCA4 expression was positively associated with tumor mutational burden, microsatellite stability, and immunotherapy efficacy. The SNHG3/THUMP3-AS1-miR-139-5p-SMARCA4 ceRNA network was established and could be assumed to serve as a stimulatory mechanism in HCC.

CONCLUSION

The findings of this study demonstrated that SMARCA4 plays a significant role in progression and immune infiltration in HCC. Moreover, a ceRNA network was detected, which was found to be correlated with poor prognosis in HCC. The findings of this study could contribute towards the identification of predictive markers for immunotherapy and a novel mechanism of action for HCC treatment.

The role of autophagy in colorectal cancer: Impact on pathogenesis and implications in therapy

Colorectal cancer (CRC) is considered as a global major cause of cancer death. Surgical resection is the main line of treatment; however, chemo-, radiotherapy and other adjuvant agents are crucial to achieve good outcomes. The tumor microenvironment (TME) is a well-recognized key player in CRC progression, yet the processes linking the cancer cells to its TME are not fully delineated. Autophagy is one of such processes, with a controversial role in the pathogenesis of CRC, with its intricate links to many pathological factors and processes. Autophagy may apparently play conflicting roles in carcinogenesis, but the precise mechanisms determining the overall direction of the process seem to depend on the context. Additionally, it has been established that autophagy has a remarkable effect on the endothelial cells in the TME, the key substrate for angiogenesis that supports tumor metastasis. Favorable response to immunotherapy occurs only in a specific subpopulation of CRC patients, namely the microsatellite instability-high (MSI-H). In view of such limitations of immunotherapy in CRC, modulation of autophagy represents a potential adjuvant strategy to enhance the effect of those relatively safe agents on wider CRC molecular subtypes. In this review, we discussed the molecular control of autophagy in CRC and how autophagy affects different processes and mechanisms that shape the TME. We explored how autophagy contributes to CRC initiation and progression, and how it interacts with tumor immunity, hypoxia, and oxidative stress. The crosstalk between autophagy and the TME in CRC was extensively dissected. Finally, we reported the clinical efforts and challenges in combining autophagy modulators with various cancer-targeted agents to improve CRC patients’ survival and restrain cancer growth.

Identification of Autophagy-Related LncRNA to Predict the Prognosis of Colorectal Cancer

Objective: To establish a prediction model based on autophagy-related lncRNAs and investigate the functional enrichment of autophagy-related lncRNAs in colorectal cancer.

Methods: TCGA database was used to extract the transcriptome data and clinical features of colorectal cancer patients. HADb was used to obtain autophagy-related genes. Pearson correlation analysis was performed to identify autophagy-related lncRNAs. The autophagy-related lncRNAs with prognostic values were selected. Based on the selected lncRNAs, the risk score model and nomogram were constructed, respectively. Calibration curve, concordance index, and ROC curve were performed to evaluate the predictive efficacy of the prediction model. GSEA was performed to figure out the functional enrichment of autophagy-related lncRNAs.

Results: A total of 13413 lncRNAs and 938 autophagy-related genes were obtained. A total of 709 autophagy-related genes were identified in colon cancer tissues, and 11 autophagy-related lncRNAs (AL138756.1, LINC01063, CD27-AS1, LINC00957, EIF3J-DT, LINC02474, SNHG16, AC105219.1, AC068580.3, LINC02381, and LINC01011) were finally selected and set as prognosis-related lncRNAs. According to the risk score, patients were divided into the high-risk and low-risk groups, respectively. The survival K–M (Kaplan–Meier) curve showed the low-risk group exhibits better overall survival than the high-risk group. The AUCs under the ROC curves were 0.72, 0.814, and 0.83 at 1, 3, and 5 years, respectively. The C-index (concordance index) of the model was 0.814. The calibration curves at 1, 3, and 5 years showed the predicting values were consistent with the actual values. Functional enrichment analysis showed that autophagy-related lncRNAs were enriched in several pathways.

Conclusions: A total of 11 specific autophagy-related lncRNAs were identified to own prognostic value in colon cancer. The predicting model based on the lncRNAs and clinical features can effectively predict the OS. Furthermore, functional enrichment analysis showed that autophagy-related genes were enriched in various biological pathways.

From Intestinal Epithelial Homeostasis to Colorectal Cancer: Autophagy Regulation in Cellular Stress

The intestinal epithelium is continuously exposed to abundant stress stimuli, which relies on an evolutionarily conserved process, autophagy, to maintain its homeostasis by degrading and recycling unwanted and damaged intracellular substances. Otherwise, disruption of this balance will result in the development of a wide range of disorders, including colorectal cancer (CRC). Dysregulated autophagy is implicated in the regulation of cellular responses to stress during the development, progression, and treatment of CRC. However, experimental investigations addressing the impact of autophagy in different phases of CRC have generated conflicting results, showing that autophagy is context-dependently related to CRC. Thus, both inhibition and activation of autophagy have been proposed as therapeutic strategies against CRC. Here, we will discuss the multifaceted role of autophagy in intestinal homeostasis and CRC, which may provide insights for future research directions.

Relief Effects of Icariin on Inflammation-Induced Decrease of Tight Junctions in Intestinal Epithelial Cells

Inflammatory cytokines including TNF-α and IL-1β impair intestinal barrier function in aging by disrupting intestinal tight junction integrity. Icariin (ICA) has a variety of pharmacological effects. Indeed, ICA produces anti-inflammatory, anti-oxidative stress, and inhibitory effects on microRNA (miRNA) expression. This study was to explore whether ICA could alleviate inflammation-associated intestinal barrier function impairment in aging and its underlying mechanism. Of particular interest, network pharmacology prediction indicated the potential therapeutic impacts of ICA for the treatment of colitis. Then, rats were used to study whether ICA has a protective effect on the reduction of tight junctions caused by inflammatory cytokines. Next, Caco-2 cell monolayers were used to explore the mechanism by which ICA alleviates the down-regulation of tight junctions. Network pharmacology prediction revealed that ICA alleviated colitis via suppressing oxidative stress. After ICA intervention, expressions of inflammatory cytokines were reduced, but tight junctions, antioxidant enzymes in aging rats were up-regulated. ICA reversed the TNF-α-induced decrease in abundance of Occludin protein in Caco-2 cell monolayers. Meanwhile, ICA alleviated the increase in permeability and expression of miR-122a. However, the protective effect of ICA was markedly attenuated after transfection with miR-122a mimics. In conclusion, ICA reduced the expressions of Occludin, Claudin1, and Claudin5 in colon, which were related to the reduction of TNF-α and IL-1β and alleviation of colonic in vivore. And ICA attenuated TNF-α-induced Occludin disruption and epithelial barrier impairment by decreasing miR-122a expression in Caco-2 cell monolayers.

Increased ATP2A1 Predicts Poor Prognosis in Patients With Colorectal Carcinoma

Colorectal cancer is one of the most common malignant tumors in the digestive system. Traditional diagnosis and treatment methods have not significantly improved the overall survival of patients. In this study, we explored the value of ATP2A1 as a biomarker in predicting the prognosis of colorectal cancer patients. We used the TCGA database to reveal the relationship between ATP2A1 mRNA level and prognosis, methylation, and immune invasion in colorectal cancer. The results showed that the expression of ATP2A1 was increased in colorectal cancer. The overall survival of patients with high expression of ATP2A1 was significantly lower than patients with low expression of ATP2A1. Cox regression analysis showed that high expression of ATP2A1 was an independent risk factor for poor prognosis in colorectal cancer patients. In addition, we used three datasets to perform a meta-analysis, which further confirmed the reliability of the results. Furthermore, we revealed that ATP2A1 could significantly inhibit the proliferation of colorectal cancer cells by inhibiting the autophagy process and was associated with several immune cells, especially CD8 + T cells. Finally, four small molecule drugs with potential inhibition of ATP2A1 expression were found by CMap analysis. This study demonstrates for the first time that ATP2A1 is a potential pathogenic factor, which may play a significant role in colorectal cancer.

Spinal anesthesia alleviates dextran sodium sulfate-induced colitis by modulating the gut microbiota

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic disease with recurrent intestinal inflammation. Although the exact etiology of IBD remains unknown, the accepted hypothesis of the pathogenesis to date is that abnormal immune responses to the gut microbiota are caused by environmental factors. The role of the gut microbiota, particularly the bidirectional interaction between the brain and gut microbiota, has gradually attracted more attention.

AIM

To investigate the potential effect of spinal anesthesia on dextran sodium sulfate (DSS)-induced colitis mice and to detect whether alterations in the gut microbiota would be crucial for IBD.

METHODS

A DSS-induced colitis mice model was established. Spinal anesthesia was administered on colitis mice in combination with the methods of cohousing and fecal microbiota transplantation (FMT) to explore the role of spinal anesthesia in IBD and identify the potential mechanisms involved.

RESULTS

We demonstrated that spinal anesthesia had protective effects against DSS-induced colitis by alleviating clinical symptoms, including reduced body weight loss, decreased disease activity index score, improved intestinal permeability and colonic morphology, decreased inflammatory response, and enhanced intestinal barrier functions. Moreover, spinal anesthesia significantly increased the abundance of Bacteroidetes, which was suppressed in the gut microbiota of colitis mice. Interestingly, cohousing with spinal anesthetic mice and FMT from spinal anesthetic mice can also alleviate DSS-induced colitis by upregulating the abundance of Bacteroidetes. We further showed that spinal anesthesia can reduce the increase in noradrenaline levels induced by DSS, which might affect the gut microbiota.

CONCLUSION

These data suggest that microbiota dysbiosis may contribute to IBD and provide evidence supporting the protective effects of spinal anesthesia on IBD by modulating the gut microbiota, which highlights a novel approach for the treatment of IBD.

Dioscin promotes autophagy by regulating the AMPK-mTOR pathway in ulcerative colitis

BACKGROUND

Dioscin is reported to alleviate the dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) in mice. Autophagy plays an anti-inflammatory role in UC. We herein aimed to explore the biological functions of dioscin in autophagy in UC.

METHODS

To explore the effects of dioscin on UC progression, a DSS-induced mouse model of UC was established. Body weight, disease activity index and macroscopic damage index scores were recorded for seven days. Hematoxylin & Eosin (HE) staining was used to stain colon sections and an BX53 microscope was prepared to observe pathological changes. The activities of glutathione, superoxidative dismutase, and malondialdehyde were determined by commercially available kits. Western blotting was performed to measure the protein levels of p-AMPK/AMPK, p-mTOR/mTOR and autophagy-related genes.

RESULTS

The DSS-induced colitis and oxidative stress in mice were ameliorated after dioscin treatment. Dioscin promoted the phosphorylation of AMPK to inhibit mTOR activation and facilitated autophagy in DSS-induced mice model of UC.

CONCLUSION

Dioscin promotes autophagy by promoting the phosphorylation of AMPK to inhibit mTOR activation in ulcerative colitis.

Redox-sensitive activation of CCL7 by BRG1 in hepatocytes during liver injury

Liver injuries induced by various stimuli share in common an acute inflammatory response, in which circulating macrophages home to the liver parenchyma to participate in the regulation of repair, regeneration, and fibrosis. In the present study we investigated the role of hepatocyte-derived C-C motif ligand 7 (CCL7) in macrophage migration during liver injury focusing on its transcriptional regulation. We report that CCL7 expression was up-regulated in the liver by lipopolysaccharide (LPS) injection (acute liver injury) or methionine-and-choline-deficient (MCD) diet feeding (chronic liver injury) paralleling increased macrophage infiltration. CCL7 expression was also inducible in hepatocytes, but not in hepatic stellate cells or in Kupffer cells, by LPS treatment or exposure to palmitate in vitro. Hepatocyte-specific deletion of Brahma-related gene 1 (BRG1), a chromatin remodeling protein, resulted in a concomitant loss of CCL7 induction and macrophage infiltration in the murine livers. Of interest, BRG1-induced CCL7 transcription and macrophage migration was completely blocked by the antioxidant N-acetylcystine. Further analyses revealed that BRG1 interacted with activator protein 1 (AP-1) to regulate CCL7 transcription in hepatocytes in a redox-sensitive manner mediated in part by casein kinase 2 (CK2)-catalyzed phosphorylation of BRG1. Importantly, a positive correlation between BRG1/CCL7 expression and macrophage infiltration was identified in human liver biopsy specimens. In conclusion, our data unveil a novel role for BRG1 as a redox-sensitive activator of CCL7 transcription.

Polysaccharides from Dendrobium officinale ameliorate colitis-induced lung injury via inhibiting inflammation and oxidative stress

It has been reported that Dendrobium officinale polysaccharides (DOPS) could alleviate colitis in animal model and suppress the activation of NLRP3 inflammasome and β-arrestin1 in vitro. However, it remains unclear whether DOPS has effect on protecting against colitis-induced pulmonary injury. The purpose of this study was to explore the protective effect and mechanism of DOPS on colitis-induced lung injury. A dextran sodium sulfate (DSS)-induced mice colitis model and lipopolysaccharide (LPS)-stimulated BEAS-2B cells model were applied in this study. The results showed that DOPS treatment restored histopathological changes, reduced inflammatory cells infiltration, pro-inflammatory cytokines levels, reactive oxygen species (ROS) formation and MDA generation, and increased anti-oxidative enzymes activities including SOD and GSH-Px in colitis mice. Further investigation showed that DOPS significantly inhibited the protein expression of TLR4, and apparently up-regulated proteins expressions of nuclear-Nrf2, HO-1 and NQO-1 in lung tissues of colitis mice and in BEAS-2B cells. These results indicated that DOPS significantly inhibited inflammation and oxidative stress to alleviate colitis-induced secondary lung injury, and its mechanisms are closely related to the inhibition of TLR4 signaling pathway and the activation of Nrf2 signaling pathway. DOPS may be a promising drug for alleviating colitis-induced lung injury.

Comparison of Sericins from Different Sources as Natural Therapeutics against Ulcerative Colitis

Sericin has become a promising natural anti-inflammatory protein. However, the biological functions of sericins largely depend on their origins; no study has yet been carried out to comparatively investigate the therapeutic effects of sericins from different sources against inflammatory diseases. Herein, we extracted and purified three kinds of sericins, namely silkworm sericin (SS), tussah sericin (TS), and castor silk sericin (CSS). These sericins showed negligible cytotoxicities against colitis-associated cells (colon epitheliums and activated macrophages). Further investigations displayed that these sericins could remarkably downregulate the secreted amounts of TNF-α, promote the recovery of the damaged colonic epithelial barrier, and eliminate endogenous reactive oxygen species in Raw 264.7 macrophages and Caenorhabditis elegans. In vivo experiments demonstrated that chitosan/alginate hydrogel-encapsulating SS could achieve efficient accumulation of SS in the colitis tissues and thereby play a more effective role in relieving ulcerative colitis (UC) than TS and CSS. Our findings collectively demonstrate that SS can be extracted, formulated, and used as a robust therapeutic agent for the oral treatment of UC.

Recent progress of autophagy signaling in tumor microenvironment and its targeting for possible cancer therapeutics

Autophagy, a lysosomal catabolic process, involves degradation of cellular materials, protein aggregate, and dysfunctional organelles to maintain cellular homeostasis. Strikingly, autophagy exhibits a dual-sided role in cancer; on the one hand, it promotes clearance of transformed cells and inhibits tumorigenesis, while cytoprotective autophagy has a role in sustaining cancer. The autophagy signaling in the tumor microenvironment (TME) during cancer growth and therapy is not adequately understood. The review highlights the role of autophagy signaling pathways to support cancer growth and progression in adaptation to the oxidative and hypoxic context of TME. Furthermore, autophagy contributes to regulating the metabolic switch for generating sufficient levels of high-energy metabolites, including amino acids, ketones, glutamine, and free fatty acids for cancer cell survival. Interestingly, autophagy has a critical role in modulating the tumor-associated fibroblast resulting in different cytokines and paracrine signaling mediated angiogenesis and invasion of pre-metastatic niches to secondary tumor sites. Moreover, autophagy promotes immune evasion to inhibit antitumor immunity, and autophagy inhibitors enhance response to immunotherapy with infiltration of immune cells to the TME niche. Furthermore, autophagy in TME maintains and supports the survival of cancer stem cells resulting in chemoresistance and therapy recurrence. Presently, drug repurposing has enabled the use of lysosomal inhibitor-based antimalarial drugs like chloroquine and hydroxychloroquine as clinically available autophagy inhibitors in cancer therapy. We focus on the recent developments of multiple autophagy modulators from pre-clinical trials and the challenges in developing autophagy-based cancer therapy.

Oral delivery of natural active small molecules by polymeric nanoparticles for the treatment of inflammatory bowel diseases

The incidence of inflammatory bowel disease (IBD) is rapidly rising throughout the world. Although tremendous efforts have been made, limited therapeutics are available for IBD management. Natural active small molecules (NASMs), which are a gift of nature to humanity, have been widely used in the prevention and alleviation of IBD; they have numerous advantageous features, including excellent biocompatibility, pharmacological activity, and mass production potential. Oral route is the most common and acceptable approach for drug administration, but the clinical application of NASMs in IBD treatment via oral route has been seriously restricted by their inherent limitations such as high hydrophobicity, instability, and poor bioavailability. With the development of nanotechnology, polymeric nanoparticles (NPs) have provided a promising platform that can efficiently encapsulate versatile NASMs, overcome multiple drug delivery barriers, and orally deliver the loaded NASMs to targeted tissues or cells while enhancing their stability and bioavailability. Thus, NPs can enhance the preventive and therapeutic effects of NASMs against IBD. Herein, we summarize the recent knowledge about polymeric matrix-based carriers, targeting ligands for drug delivery, and NASMs. We also discuss the current challenges and future developmental directions.