Hepatic stellate cells (HSCs) are the primary fibrogenic cells in the liver, and their activation plays a crucial role in the development and progression of hepatic fibrosis. Here, we report that retinoid X receptor-alpha (RXRα), a unique member of the nuclear receptor superfamily, is a key modulator of HSC activation and liver fibrosis. RXRα exerts its effects by modulating calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ)-mediated activation of AMP-activated protein kinase-alpha (AMPKα). In addition, we demonstrate that K-80003, which binds RXRα by a unique mechanism, effectively suppresses HSC activation, proliferation, and migration, thereby inhibiting liver fibrosis in the CCl₄ and amylin liver NASH (AMLN) diet animal models. The effect is mediated by AMPKα activation, promoting mitophagy in HSCs. Mechanistically, K-80003 activates AMPKα by inducing RXRα to form condensates with CaMKKβ and AMPKα via a two-phase process. The formation of RXRα condensates is driven by its N-terminal intrinsic disorder region and requires phosphorylation by CaMKKβ. Our results reveal a crucial role of RXRα in liver fibrosis regulation through modulating mitochondrial activities in HSCs. Furthermore, they suggest that K-80003 and related RXRα modulators hold promise as therapeutic agents for fibrosis-related diseases.

The incomplete degradation of tumour cells by macrophages(Mφ)is a contributing factor to tumour progression and metastasis,and the degradation function of Mφ is mediated through phagosomes and lysosomes.In our preliminary experiments,we found that overactivation of NADPH oxidase 2(NOX2)reduced the ability of Mφ to degrade engulfed tumour cells.Above this,we screened out liquiritin from Glycyrrhiza uralensis Fisch,which can significantly inhibit NOX2 activity and inhibit tumours,to elucidate that suppressing NOX2 can enhance the ability of Mφ to degrade tumour cells.We found that the tumour environment could activate the NOX2 activity in Mφ phagosomes,causing Mφ to produce excessive reactive oxygen species(ROS),thus prohibiting the formation of phagolysosomes before degradation.Conversely,inhibiting NOX2 in Mφ by liquiritin can reduce ROS and promote phagosome-lysosome fusion,therefore improving the enzymatic degradation of tumour cells after phagocytosis,and subse-quently promote T cell activity by presenting antigens.We further confirmed that liquiritin down-regulated the expression of the NOX2 specific membrane component protein gp91 phox,blocking its binding to the NOX2 cytoplasmic component proteins p67 phox and p47 phox,thereby inhibiting the activity of NOX2.This study elucidates the specific mechanism by which Mφ cannot degrade tumour cells after phagocytosis,and indicates that liquiritin can promote the ability of Mφ to degrade tumour cells by suppressing NOX2.

The incomplete degradation of tumour cells by macrophages (Mϕ) is a contributing factor to tumour progression and metastasis, and the degradation function of Mϕ is mediated through phagosomes and lysosomes. In our preliminary experiments, we found that overactivation of NADPH oxidase 2 (NOX2) reduced the ability of Mϕ to degrade engulfed tumour cells. Above this, we screened out liquiritin from Glycyrrhiza uralensis Fisch, which can significantly inhibit NOX2 activity and inhibit tumours, to elucidate that suppressing NOX2 can enhance the ability of Mϕ to degrade tumour cells. We found that the tumour environment could activate the NOX2 activity in Mϕ phagosomes, causing Mϕ to produce excessive reactive oxygen species (ROS), thus prohibiting the formation of phagolysosomes before degradation. Conversely, inhibiting NOX2 in Mϕ by liquiritin can reduce ROS and promote phagosome-lysosome fusion, therefore improving the enzymatic degradation of tumour cells after phagocytosis, and subsequently promote T cell activity by presenting antigens. We further confirmed that liquiritin down-regulated the expression of the NOX2 specific membrane component protein gp91 phox, blocking its binding to the NOX2 cytoplasmic component proteins p67 phox and p47 phox, thereby inhibiting the activity of NOX2. This study elucidates the specific mechanism by which Mϕ cannot degrade tumour cells after phagocytosis, and indicates that liquiritin can promote the ability of Mϕ to degrade tumour cells by suppressing NOX2.

Objective:To explore whether LBP3 exerts anti-tumor effects by promoting production of short-chain fatty acids(SCFAs)by intestinal microbiota and regulating function of polymorphonuclear myeloid-derived suppressor cells(PMN-MDSC).Methods:A subcutaneous H22 liver cancer model was employed to assess anti-tumor activity of LBP3 and its regulatory effects on PMN-MDSC.Pseudo-sterile tumor-bearing mouse model was used to investigate role of intestinal microbiota in tumor suppression of LBP3.Fecal microbiota transplantation(FMT)was conducted to explore immune regulatory role of LBP3-modulated flora.Serum SCFAs levels in tumor-bearing mice were quantified using liquid chromatography-mass spectrometry,and effect of SCFAs butyrate on arginase 1(Arg-1)expression was evaluated in vitro.Results:Both low-dose(125 mg/kg)and high-dose(250 mg/kg)LBP3 signifi-cantly inhibited tumor growth in H22 tumor-bearing mice,also led to a marked reduction in proportion of PMN-MDSC in both spleen and tumor,a reduced proportion of Treg in lymphoid tissues,a decrease in Arg-1 level within tumor,infiltration of CD8+T cells into tumor was significantly enhanced.However,these effects of LBP3 were did not observed in pseudo-sterile mice,while the above changes could be reproduced after fecal supernatant transplantation in high-dose LBP3 treatment group,suggesting a crucial role for gut microbiota.Furthermore,co-expression of Ly6G and SCFA receptor GPR43 in tumor was also observed.LBP3 treatment resulted in increased levels of SCFAs,particularly butyrate,in both blood and tumor tissues.In vitro,butyrate was shown to inhibit Arg-1 expression in MSC-2 cells,further supporting hypothesis that SCFAs mediate immune-modulatory effects of LBP3.Conclusion:LBP3 exerts its anti-tumor effects by promoting SCFA production,which subsequently inhibits function of PMN-MDSC.This highlights LBP3's potential as an immunomodulatory agent in cancer therapy.

Objective:To explore whether LBP3 exerts anti-tumor effects by promoting production of short-chain fatty acids(SCFAs)by intestinal microbiota and regulating function of polymorphonuclear myeloid-derived suppressor cells(PMN-MDSC).Methods:A subcutaneous H22 liver cancer model was employed to assess anti-tumor activity of LBP3 and its regulatory effects on PMN-MDSC.Pseudo-sterile tumor-bearing mouse model was used to investigate role of intestinal microbiota in tumor suppression of LBP3.Fecal microbiota transplantation(FMT)was conducted to explore immune regulatory role of LBP3-modulated flora.Serum SCFAs levels in tumor-bearing mice were quantified using liquid chromatography-mass spectrometry,and effect of SCFAs butyrate on arginase 1(Arg-1)expression was evaluated in vitro.Results:Both low-dose(125 mg/kg)and high-dose(250 mg/kg)LBP3 signifi-cantly inhibited tumor growth in H22 tumor-bearing mice,also led to a marked reduction in proportion of PMN-MDSC in both spleen and tumor,a reduced proportion of Treg in lymphoid tissues,a decrease in Arg-1 level within tumor,infiltration of CD8+T cells into tumor was significantly enhanced.However,these effects of LBP3 were did not observed in pseudo-sterile mice,while the above changes could be reproduced after fecal supernatant transplantation in high-dose LBP3 treatment group,suggesting a crucial role for gut microbiota.Furthermore,co-expression of Ly6G and SCFA receptor GPR43 in tumor was also observed.LBP3 treatment resulted in increased levels of SCFAs,particularly butyrate,in both blood and tumor tissues.In vitro,butyrate was shown to inhibit Arg-1 expression in MSC-2 cells,further supporting hypothesis that SCFAs mediate immune-modulatory effects of LBP3.Conclusion:LBP3 exerts its anti-tumor effects by promoting SCFA production,which subsequently inhibits function of PMN-MDSC.This highlights LBP3's potential as an immunomodulatory agent in cancer therapy.

Objective To investigate the effect of E2 signaling in myofibers on muscular macrophage efferocytosis in mice with cardiotoxin-induced acute skeletal muscle injury.Methods Female wild-type C57BL/6 mice with and without ovariectomy and male C57BL/6 mice were given a CTX injection into the anterior tibial muscle to induce acute muscle injury,followed by intramuscular injection of β-estradiol(E2)or 4-hydroxytamoxifen(4-OHT).The changes in serum E2 of the mice were detected using ELISA,and the number,phenotypes,and efferocytosis of the macrophages in the inflammatory exudates and myofiber regeneration and repair were evaluated using immunofluorescence staining and flow cytometry.C2C12 cells were induced to differentiate into mature myotubes,which were treated with IFN-γ for 24 before treatment with β-Estradiol or 4-OHT.The treated myotubes were co-cultured with mouse peritoneal macrophages in a 1:2 ratio,followed by addition of PKH67-labeled apoptotic mouse mononuclear spleen cells induced by UV irradiation,and macrophage efferocytosis was observed using immunofluorescence staining and flow cytometry.Results Compared with the control mice,the female mice with ovariectomy showed significantly increased mononuclear macrophages in the inflammatory exudates,with increased M1 cell percentage,reduced M2 cell percentage and macrophage efferocytosis in the injured muscle,and obviously delayed myofiber regeneration and repair.In the cell co-culture systems,treatment of the myotubes with β-estradiol significantly increased the number and proportion of M2 macrophages and macrophage efferocytosis,while 4-OHT treatment resulted in the opposite changes.Conclusion In injured mouse skeletal muscles,myofiber E2 signaling promotes M1 to M2 transition to increase macrophage efferocytosis,thereby relieving inflammation and promoting muscle regeneration and repair.

With the increasing incidence of diabetes mellitus in recent years， cardiomyopathy caused by diabetes mellitus has aroused wide concern and this disease is characterized by high insidiousness and high mortality. The early pathological changes of diabetic cardiomyopathy （DCM） are mitochondrial structural disorders and loss of myocardial metabolic flexibility. The turbulence of mitochondrial quality control （MQC） is a key mechanism leading to the accumulation of damaged mitochondria and loss of myocardial metabolic flexibility， which， together with elevated levels of oxidative stress and inflammation， trigger changes in myocardial structure and function. Qi deficiency and stagnation is caused by the loss of healthy Qi， and the dysfunction of Qi transformation results in the accumulation of pathogenic Qi， which further triggers injuries. According to the theory of traditional Chinese medicine （TCM）， DCM is rooted in Qi deficiency of the heart， spleen， and kidney. The dysfunction of Qi transformation leads to the generation and lingering of turbidity， stasis， and toxin in the nutrient-blood and vessels， ultimately damaging the heart. Therefore， Qi deficiency and stagnation is the basic pathologic mechanism of DCM. Mitochondria， similar to Qi in substance and function， are one of the microscopic manifestations of Qi. The role of MQC is consistent with the defense function of Qi. In the case of MQC turbulence， mitochondrial structure and function are impaired. As a result， Qi deficiency gradually emerges and triggers pathological changes， which make it difficult to remove the stagnant pathogenic factor and aggravates the MQC turbulence. Ultimately， DCM occurs. Targeting MQC to treat DCM has become the focus of current research， and TCM has the advantages of acting on multiple targets and pathways. According to the pathogenesis of Qi deficiency and stagnation in DCM and the modern medical understanding of MQC， the treatment should follow the principles of invigorating healthy Qi， tonifying deficiency， and regulating Qi movement. This paper aims to provide ideas for formulating prescriptions and clinical references for the TCM treatment of DCM by targeting MQC.

Objective To investigate the effect of E2 signaling in myofibers on muscular macrophage efferocytosis in mice with cardiotoxin-induced acute skeletal muscle injury.Methods Female wild-type C57BL/6 mice with and without ovariectomy and male C57BL/6 mice were given a CTX injection into the anterior tibial muscle to induce acute muscle injury,followed by intramuscular injection of β-estradiol(E2)or 4-hydroxytamoxifen(4-OHT).The changes in serum E2 of the mice were detected using ELISA,and the number,phenotypes,and efferocytosis of the macrophages in the inflammatory exudates and myofiber regeneration and repair were evaluated using immunofluorescence staining and flow cytometry.C2C12 cells were induced to differentiate into mature myotubes,which were treated with IFN-γ for 24 before treatment with β-Estradiol or 4-OHT.The treated myotubes were co-cultured with mouse peritoneal macrophages in a 1:2 ratio,followed by addition of PKH67-labeled apoptotic mouse mononuclear spleen cells induced by UV irradiation,and macrophage efferocytosis was observed using immunofluorescence staining and flow cytometry.Results Compared with the control mice,the female mice with ovariectomy showed significantly increased mononuclear macrophages in the inflammatory exudates,with increased M1 cell percentage,reduced M2 cell percentage and macrophage efferocytosis in the injured muscle,and obviously delayed myofiber regeneration and repair.In the cell co-culture systems,treatment of the myotubes with β-estradiol significantly increased the number and proportion of M2 macrophages and macrophage efferocytosis,while 4-OHT treatment resulted in the opposite changes.Conclusion In injured mouse skeletal muscles,myofiber E2 signaling promotes M1 to M2 transition to increase macrophage efferocytosis,thereby relieving inflammation and promoting muscle regeneration and repair.

At present, external treatment of traditional Chinese medicine (TCM) has been widely used in the treatment of intestinal obstruction, which is safe and effective. This study reported a case of recurrent intestinal obstruction after radiotherapy and chemotherapy for rectal cancer. After the implementation of external treatment of TCM on the basis of conventional western medicine treatment, the patient's condition improved significantly, and the patient was discharged smoothly. This case aimed to provide a reference for the diagnosis and treatment of this disease.

Objective: To investigate the effects and mechanism of diammonium glycyrrhizinate (DG) on liver injury in severely scalded rats. Methods: The experimental research method was used. Fifty-four female Sprague-Dawley rats aged 7-9 weeks were divided into sham injury group with simulated injury on the back, and simple scald group and scald+DG group with scald of 30% total body surface area on the back, with 18 rats in each group. Rats in sham injury group were not specially treated after injury, and rats in simple scald group and scald+DG group were rehydrated for antishock. Besides, rats in scald+DG group were injected intraperitoneally with 50 mg/kg DG at post injury hour (PIH) 1, 25, and 49. Rats in the three groups were collected, the serum content of liver function injury related indexes including aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), total protein, and albumin was measured by automatic biochemical assay analyzer, and serum content of ornithine carbamoyl transferase (OCT) was measured by enzyme-linked immunosorbent assay method at PIH 24, 48, and 72; hepatic histopathological changes at PIH 72 were observed by hematoxylin-eosin staining; the mRNA expressions of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), glucose regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), and protein kinase R-like endoplasmic reticulum kinase (PERK) in liver tissue were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction at PIH 24, 48, and 72. The protein expressions of Bcl-2, Bax, GRP78, PERK, and ATF4 in liver tissue were detected by Western blotting at PIH 72 in sham injury group and PIH 24, 48, and 72 in simple scald group and scald+DG group. The number of samples was 6 in each group at each time point. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, and Bonferroni test. Results: Compared with that in sham injury group, the serum content of AST, ALT, and LDH was significantly increased (P<0.01), and the serum content of total protein and albumin was significantly decreased (P<0.05 or P<0.01) of rats in simple scald group at all post-injury time points. Compared with those in simple scald group, the serum AST content of rats in scald+DG group at PIH 24 was decreased significantly (P<0.05); the serum AST, ALT, and LDH content of rats in scald+DG group at PIH 48 was decreased significantly (P<0.01), and the serum total protein content was increased significantly (P<0.01); the serum AST, ALT, and LDH content of rats in scald+DG group at PIH 72 was decreased significantly (P<0.01), and the serum total protein and albumin content was increased significantly (P<0.01). At PIH 24, 48, and 72, the serum OCT content of rats in simple scald group was (48.5±3.9), (40.8±2.4), and (38.7±2.0) U/L, which was significantly higher than (15.1±2.5), (15.7±2.6), and (16.4±3.7) U/L in sham injury group (P<0.01), and (39.0±4.5), (31.8±2.0), and (22.1±2.6) U/L in scald+DG group (P<0.05 or P<0.01). At PIH 72, the cells in liver tissue of rats in sham injury group had normal morphology and regular arrangement, with no obvious inflammatory cell infiltration; the cells in liver tissue of rats in simple scald group had disordered arrangement, diffuse steatosis, and moderate inflammatory cell infiltration; the cells in liver tissue of rats in scald+DG group arranged regularly, with scattered steatosis and a small amount of inflammatory cell infiltration. Compared with those in sham injury group, the Bcl-2 mRNA (P<0.05 or P<0.01) and protein expressions of liver tissue were significantly decreased, and the mRNA (P<0.01) and protein expressions of Bax were significantly increased in rats in simple scald group at PIH 24, 48, and 72. Compared with those in simple scald group, the mRNA (P<0.05) and protein expressions of Bax in liver tissue of rats in scald+DG group were decreased significantly at PIH 48; the mRNA (P<0.01) and protein expressions of Bax in liver tissue of rats in scald+DG group were significantly decreased, and the mRNA (P<0.01) and protein expressions of Bcl-2 were significantly increased at PIH 72. Compared with those in sham injury group, the mRNA (P<0.05 or P<0.01) and protein expressions of ATF4, GRP78, and PERK in liver tissue were significantly increased in rats in simple scald group at all post-injury time points. Compared with those in simple scald group, the mRNA (P<0.01) and protein expressions of ATF4 in liver tissue of rats in scald+DG group at PIH 48 were significantly decreased, and the mRNA (P<0.05 or P<0.01) and protein expressions of ATF4, GRP78, and PERK were significantly decreased in liver tissue of rats in scald+DG group at PIH 72. Conclusions: DG can effectively reduce the degree of liver injury in rats after severe scald, and the mechanism may involve alleviating endoplasmic reticulum stress and mitigating mitochondrial damage.
Albumins/pharmacology* ; Animals ; Burns/pathology* ; Female ; Glycyrrhizic Acid/pharmacology* ; Liver ; RNA, Messenger/genetics* ; Rats ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein/pharmacology*