Koumine regulates macrophage M1/M2 polarization via TSPO, alleviating sepsis-associated liver injury in mice.

BACKGROUND: Translocator protein (TSPO) is an 18-kDa transmembrane protein found primarily in the mitochondrial outer membrane, and it is implicated in inflammatory responses, such as cytokine release. Koumine (KM) is an indole alkaloid extracted from Gelsemium elegans Benth. It has been reported to be a high-affinity ligand of TSPO and to exert anti-inflammatory and immunomodulatory effects in our recent studies. However, the protective effect of KM on sepsis-associated liver injury (SALI) and its mechanisms are unknown. PURPOSE: To explore the role of TSPO in SALI and then further explore the protective effect and mechanism of KM on SALI. METHODS: The effect of KM on the survival rate of septic mice was confirmed in mouse models of caecal ligation and puncture (CLP)-induced and lipopolysaccharide (LPS)-induced sepsis. The protective effect of KM on CLP-induced SALI was comprehensively evaluated by observing the morphology of the mouse liver and measuring liver injury markers. The serum cytokine content was detected in mice by flow cytometry. Macrophage polarization in the liver was examined using western blotting. TSPO knockout mice were used to explore the role of TSPO in sepsis liver injury and verify the protective effect of KM on sepsis liver injury through TSPO. RESULTS: KM significantly improved the survival rate of both LPS- and CLP-induced sepsis in mice. KM has a significant liver protective effect on CLP-induced sepsis in mice. KM treatment ameliorated liver ischaemia, improved liver pathological injuries, and decreased the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and proinflammatory cytokines in serum. Western blotting results showed that KM inhibited M1 polarization of macrophages and promoted M2 polarization. In TSPO knockout mice, we found that TSPO knockout can improve the survival rate of septic mice, ameliorate liver ischaemia, improve liver pathological injuries, and decrease the levels of ALT, AST, and LDH. In addition, TSPO knockout inhibits the M1 polarization of macrophages in the liver of septic mice and promotes M2 polarization and the serum levels of proinflammatory cytokines. Interestingly, in TSPO knockout septic mice, these protective effects of KM were no longer effective. CONCLUSIONS: We report for the first time that TSPO plays a critical role in sepsis-associated liver injury by regulating the polarization of liver macrophages and reducing the inflammatory response. KM, a TSPO ligand, is a potentially desirable candidate for the treatment of SALI that may regulate macrophage M1/M2 polarization through TSPO in the liver.

Up-regulation of hepatic CD36 by increased corticosterone/cortisol levels via GR leads to lipid accumulation in liver and hypertriglyceridaemia during pregnancy.

BACKGROUND AND PURPOSE: Plasma triglyceride (TG) levels increase as gestation proceeds, and abnormal elevation of TG increases the risk of pregnancy complications. The current study explored the mechanisms involved in hypertriglyceridaemia during pregnancy. EXPERIMENTAL APPROACH: Lipid profile and expression levels of key genes involved in liver TG metabolism in non-pregnant and pregnant mice were studied. The effects of pregnancy-related hormones on key genes and the underlying mechanisms were uncovered in vitro and in vivo. KEY RESULTS: Plasma and hepatic TG levels were elevated, while hepatic fatty acid translocase (FAT/CD36) was up-regulated in pregnant mice. Corticosterone and cortisol (endogenous glucocorticoids that are elevated during pregnancy), but not oestradiol or progesterone, significantly up-regulated CD36 in hepatocytes, and this was abolished after knockdown of the glucocorticoid receptor (GR) using a siRNA or in the presence of GR antagonists, RU486 and AL082D06. The luciferase reporter gene and chromatin immunoprecipitation assay further revealed that corticosterone/cortisol promoted the direct binding of GR to the CD36 promoter and up-regulated its transcription. Chronic corticosterone exposure induced liver lipid accumulation and increased plasma TG levels in mice, which were attenuated by RU486 via inhibition of the GR-CD36 pathway. CONCLUSIONS AND IMPLICATIONS: Increased corticosterone/cortisol induces liver lipid accumulation and hypertriglyceridaemia during pregnancy by accelerating fatty acid uptake into hepatocytes via activation of GR and its target gene, CD36. Our results may be useful for the prevention of severe hypertriglyceridaemia and associated pregnancy complications.

Biological protein mediated ferroptotic tumor nanotherapeutics.

Ferroptosis, a cell death pathway involving iron-related generation of lipid hydroperoxides for achieving incredible tumor suppression, has reignited the hope of chemotherapy in tumor treatment in the past decade. With extensive research studies, various bioactive proteins and cellular pathways have been demonstrated to regulate the occurrence and development of ferroptosis. The gradually established ferroptotic regulatory network is conducive to find effective proteins from a holistic perspective and guides better designs for future ferroptotic tumor therapies. The first section of this review summarizes the recent advances in ferroptotic regulatory mechanisms of proteins and attempts to clarify their latent function in the ferroptotic regulatory network. Second, the existing protein-mediated ferroptotic tumor nanotherapeutic strategies were reviewed, including the protein-mediated iron supplement, cell membrane transporter inhibition, glutathione peroxidase 4 interference, glutathione depletion, bioenzyme-mediated reactive oxygen species generation, heat shock protein inhibition, and tumor-overexpressed protein-triggered drug release for ferroptotic therapy. Finally, the future expectations and challenges of ferroptotic tumor nanotherapeutics for clinical cancer therapy are highlighted.

Downregulation of OCTN2 by cytokines plays an important role in the progression of inflammatory bowel disease.

Inflammatory bowel diseases (IBD) are characterized by chronic relapsing disorders of the gastrointestinal tract. OCTN2 (SLC22A5) and its substrate l-carnitine (l-Car) play crucial roles in maintaining normal intestinal function. An aim of this study was to delineate the expression alteration of OCTN2 in IBD and its underlying mechanism. We also investigated the impact of OCTN2 on IBD progression and the possibility of improving IBD through OCTN2 regulation. Our results showed decreased OCTN2 expression levels and l-Car content in inflamed colon tissues of IBD patients and mice, which negatively correlated with the degree of colonic inflammation in IBD mice. Mixed proinflammatory cytokines TNF-α, IL-1ß and IFNγ downregulated the expression of OCTN2 and subsequently reduced the l-Car content through PPARγ/RXRα pathways in FHC cells. OCTN2 silencing reduced the proliferation rate of the colon cells, whereas OCTN2 overexpression increased the proliferation rate. Furthermore, the ability of PPARγ agonist, luteolin, to increase OCTN2 expression resulted in the alleviation of colonic inflammatory responses. In conclusion, OCTN2 was downregulated in IBD by proinflammatory cytokines via the PPARγ/RXRα pathways, which reduced l-Car concentration and subsequently induced IBD deterioration. Upregulation of OCTN2 by the PPARγ agonist alleviated colonic inflammation. Our findings suggest that, OCTN2 may serve as a therapeutic target for IBD therapy.

[A real-world study of low molecular weight heparin sodium in the treatment of severe and critical bite by Trimeresurus stejnegeri].

OBJECTIVE: To investigate the clinical effect of low molecular weight heparin sodium combined with antivenin in the treatment of severe and critical bite by Trimeresurus stejnegeri. METHODS: The clinical data of 48 patients with severe or critical bite by Trimeresurus stejnegeri admitted to emergency department of Southeast Hospital Affiliated to Xiamen University from March 2017 to May 2019 were retrospectively analyzed. On the basis of early treatment of antivenom serum, internal administration and external application of Jidesheng snake tablet, and wound incision and detoxification, the patients were divided into heparin treatment group and non-heparin treatment group according to whether the low molecular heparin sodium was used or not. The patients in the two groups were compared in terms of gender, age, clinical classification, swelling degree of injured limbs, change of coagulation function index, bleeding of skin, mucous membrane or digestive tract, blood transfusion, local symptoms of bite, length of hospital stay and prognosis. RESULTS: There was no significant difference in terms of gender, age, clinical classification or swelling degree of injured limbs between the two groups. On the 3rd day of treatment, the platelet count (PLT) in the heparin treatment group was significantly higher than that in the non-heparin treatment group [×109/L: 210.0 (160.0, 252.0) vs. 136.0 (104.0, 198.5), P < 0.05]. However, there was no significant difference in the four coagulation test results between the two groups. On the 6th day of treatment, the plasma thrombin time (TT) in the heparin treatment group was significantly shorter than that on the 3rd day of treatment [s: 30.3 (20.4, 37.0) vs. 34.7 (24.0, 73.4), P < 0.05], and the fibrinogen (FIB) in the heparin treatment group was significantly higher than that in the non-heparin treatment group [g/L: 0.60 (0.31, 1.07) vs. 0.20 (0.14, 0.60), P < 0.01]. The incidence of bleeding in the heparin treatment group was significantly lower than that in the non-heparin treatment group [21.7% (5/23) vs. 64.0% (16/25), P < 0.01]; 11 patients in the heparin treatment group and 18 patients in the non-heparin treatment group received blood transfusion and prothrombin complex supplement respectively. There was no significant difference in the length of hospital stay between the heparin group and non-heparin treatment group (days: 6.91±1.92 vs. 7.48±2.27, P > 0.05). The patients in both groups were followed up for 1 week to 1 month after treatment, and no death or local necrosis of skin and soft tissue was found. CONCLUSIONS: For the patients with severe and critical bite by Trimeresurus stejnegeri, on the basis of injection of antivenom serum, internal administration and external application of Jidesheng snake tablet, and wound incision and detoxification, early application of low molecular weight heparin sodium anticoagulation and other comprehensive treatment is helpful to improve limb swelling and inflammation, reduce blood transfusion, promote the recovery of coagulation function, and shorten the length of hospitalization.

Bioinformatic identification of renal cell carcinoma microenvironment-associated biomarkers with therapeutic and prognostic value.

Renal cell carcinoma (RCC) is the ninth most prevalent form of malignancy worldwide. The tumor microenvironment significantly affects gene expression in tumor tissues, which subsequently impacts the prognosis of RCC patients. Available datasets such as The Cancer Genome Atlas (TCGA) can be utilized to improve diagnostic methods and search for novel tumor therapeutic targets and prognostic biomarkers. The current study used the ESTIMATE algorithm to explore the immune and stromal components in RCC. Differentially expressed genes (DEGs) were identified by comparing the gene expression patterns in groups with high and low immune/stromal scores. Functional enrichment analysis was conducted and Kaplan-Meier survival curves were plotted to explore the functions of the DEGs in the tumorigenesis, progression, and prognosis of RCC. Our results revealed that immune and stromal scores are associated with specific clinicopathologic variables in RCC. These variables include gender, tumor grade, tumor stage, tumor size, distant metastasis and prognosis. A total of 48 upregulated and 47 downregulated genes were obtained. Functional enrichment analysis demonstrated a correlation between DEGs and the tumor microenvironment, tumor immune response and RCC tumorigenesis. Kaplan-Meier survival curves showed that 43 out of the 48 identified tumor microenvironment related genes are involved in the prognosis of RCC. Three genes, IL10, IGLL5 and POU2AF1, were selected as the hub genes, and their kinase targets were identified as MAPK1 and PPKCA. A positive correlation was obtained between the expression of IL/POU2AF1 and the abundance of six immune cells. Our study provides potential biomarkers for the therapy and prognosis of RCC.

Multiple Drug Transporters Contribute to the Placental Transfer of Emtricitabine.

Emtricitabine (FTC) is a first-line antiviral drug recommended for the treatment of AIDS during pregnancy. We hypothesized that transporters located in the placenta contribute to FTC transfer across the blood-placenta barrier. BeWo cells, cell models with stable or transient expression of transporter genes, primary human trophoblast cells (PHTCs), and small interfering RNAs (siRNAs) were applied to demonstrate which transporters were involved. FTC accumulation in BeWo cells was reduced markedly by inhibitors of equilibrative nucleoside transporters (ENTs), concentrative nucleoside transporters (CNTs), organic cation transporters (OCTs), and organic cation/carnitine transporter 1 (OCTN1) and increased by inhibitors of breast cancer resistance protein (BCRP) and multidrug resistance-associated proteins (MRPs). ENT1, CNT1, OCTN1, MRP1/2/3, and BCRP, but not ENT2, CNT3, OCTN2, or multidrug resistance protein 1 (MDR1), were found to transport FTC. FTC accumulation in PHTCs was decreased significantly by inhibitors of ENTs and OCTN1. These results suggest that ENT1, CNT1, and OCTN1 probably contribute to FTC uptake from maternal circulation to trophoblasts and that ENT1, CNT1, and MRP1 are likely involved in FTC transport between trophoblasts and fetal blood, whereas BCRP and MRP1/2/3 facilitate FTC transport from trophoblasts to maternal circulation. Coexistence of tenofovir or efavirenz with FTC in the cell medium did not influence FTC accumulation in BeWo cells or PHTCs.

Maternal Plasma l-Carnitine Reduction During Pregnancy Is Mainly Attributed to OCTN2-Mediated Placental Uptake and Does Not Result in Maternal Hepatic Fatty Acid ß-Oxidation Decline.

l-Carnitine (l-Car) plays a crucial role in fatty acid ß-oxidation. However, the plasma l-Car concentration in women markedly declines during pregnancy, but the underlying mechanism and its consequences on maternal hepatic ß-oxidation have not yet been clarified. Our results showed that the plasma l-Car level in mice at gestation day (GD) 18 was significantly lower than that in nonpregnant mice, and the mean fetal-to-maternal plasma l-Car ratio in GD 18 mice was 3.0. Carnitine/organic cation transporter 2 (OCTN2) was highly expressed in mouse and human placenta and upregulated as gestation proceeds in human placenta, whereas expressions of carnitine transporter (CT) 1, CT2, and amino acid transporter B0,+ were extremely low. Further study revealed that renal peroxisome proliferator-activated receptor α (PPARα) and OCTN2 were downregulated and the renal l-Car level was reduced, whereas the urinary excretion of l-Car was lower in late pregnant mice than in nonpregnant mice. Meanwhile, progesterone (pregnancy-related hormone) downregulated the expression of renal OCTN2 via PPARα-mediated pathway, and inhibited the activity of OCTN2, but estradiol, corticosterone, and cortisol did not. Unexpectedly, the maternal hepatic level of l-Car and ß-hydroxybutyrate (an indicator of mitochondrial ß-oxidation), and mRNA levels of several enzymes involved in fatty acid ß-oxidation in GD 18 mice were higher than that in nonpregnant mice. In conclusion, OCTN2 mediated l-Car transfer across the placenta played a major role in maternal plasma l-Car reduction during pregnancy, which did not subsequently result in maternal hepatic fatty acid ß-oxidation decrease.

Identification of Therapeutic Targets and Prognostic Biomarkers Among CXC Chemokines in the Renal Cell Carcinoma Microenvironment.

Background: Renal cell carcinoma (RCC) is one of the most common malignances with an ever-increasing incidence and high mortality. Cross-talk between cancer cells and interstitial cells exerts significant effects on neoplasia and tumor development and is modulated in part by chemokines. CXC chemokines in the tumor microenvironment can modulate immune cell trafficking and regulate tumor cell activities, thus exerting anti-tumor immunological effects and affecting patient outcomes; however, the expression and prognostic values of CXC chemokines in RCC have not been clarified. Methods: ONCOMINE, GEPIA, UALCAN, cBioPortal, GeneMANIA, DAVID 6.8, Metascape, TRRUST, LinkedOmics, and TIMER were utilized in this study. Results: The transcriptional levels of CXCL1/2/5/6/9/10/11/16 in RCC tissues were significantly elevated while the transcriptional levels of CXCL3/7/12/13 were significantly reduced. A significant correlation was found between the expression of CXC1/5/9/10/11/13 and the pathological stage of RCC patients. RCC patients with low transcriptional levels of CXCL1/2/3/5/13 were associated with a significantly better prognosis. The functions of differentially expressed CXC chemokines are primarily related to the chemokine signaling pathway, cytokine-cytokine receptor interactions, and the ILK signaling pathway. Our data suggest that RELA, NFKB1, and SP1 are key transcription factors for CXC chemokines, and the SRC family of tyrosine kinases (LCK, LYN, and FYN), mitogen-activated protein kinases (MAPK1 and MAPK3), and CSNK1D are CXC chemokine targets. We found significant correlations among the expression of CXC chemokines and the infiltration of six types of immune cells (B cells, CD8+ T cells, CD4+ T cells, macrophages, neutrophils, and dendritic cells). Conclusions: Our results may provide novel insights for the selection of immunotherapeutic targets and prognostic biomarkers for renal cell carcinoma.