Glutathione S-Transferase α4 Alleviates Hyperlipidemia-Induced Vascular Neointimal Hyperplasia in Arteriovenous Grafts via Inhibiting Endoplasmic Reticulum Stress.

ABSTRACT: Neointimal hyperplasia causes the failure of coronary artery bypass grafting. Our previous studies have found that endothelial dysfunction is 1 candidate for triggering neointimal hyperplasia, but which factors are involved in this process is unclear. Glutathione S-transferase α4 (GSTA4) plays an important role in metabolizing 4-hydroxynonenal (4-HNE), a highly reactive lipid peroxidation product, which causes endothelial dysfunction or death. Here, we investigated the role of GSTA4 in neointima formation after arteriovenous grafts (AVGs) with or without high-fat diet (HFD). Compared with normal diet, HFD caused endothelial dysfunction and increased neointima formation, concomitantly accompanied by downregulated expression of GSTA4 at the mRNA and protein levels. In vitro, overexpression of GSTA4 attenuated 4-HNE-induced endothelial dysfunction and knockdown of GSTA4 aggravated endothelial dysfunction. Furthermore, silencing GSTA4 expression facilitated the activation of 4-HNE-induced endoplasmic reticulum stress and inhibition of endoplasmic reticulum stress pathway alleviated 4-HNE-induced endothelial dysfunction. In addition, compared with wild-type mice, mice with knockout of endothelial-specific GSTA4 (GSTA4 endothelial cell KO) exhibited exacerbated vascular endothelial dysfunction and increased neointima formation caused by HFD. Together, these results demonstrate the critical role of GSTA4 in protecting the function of endothelial cells and in alleviating hyperlipidemia-induced vascular neointimal hyperplasia in arteriovenous grafts.

Endoplasmic reticulum stress promotes sepsis-induced muscle atrophy via activation of STAT3 and Smad3.

Endoplasmic reticulum (ER) stress is involved in skeletal muscle atrophy in various conditions, but the role of ER stress in sepsis-induced muscle atrophy is not well understood. In this study, we conducted experiments in wild-type (WT) mice and C/EBP homologous protein knockout (CHOP KO) mice to explore the role and mechanism of ER stress in sepsis-induced muscle atrophy. Cecal ligation and puncture (CLP) was used to establish a mouse model of sepsis. In WT mice, the body weight, muscle mass, and cross-sectional area of muscle fibers in CLP group both decreased significantly compared with sham group, which revealed that sepsis-induced dramatic muscle atrophy. Additionally, sepsis activated the ubiquitin-proteasome system (UPS), accompanied by the activation of ER stress. In vitro, inhibition of ER stress suppressed the activity of E3 ubiquitin ligases and alleviated the myotube atrophy. In vivo, CHOP KO also reduced the expression of E3 ubiquitin ligases and UPS-mediated protein degradation, and significantly attenuated sepsis-induced muscle atrophy. Deletion of CHOP also decreased the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and Smad3, and inhibition of STAT3 and Smad3 partly reduced proteolysis caused by ER stress in vitro. These findings confirm that ER stress activates UPS-mediated proteolysis and promotes sepsis-induced muscle atrophy, which is partly achieved by activating STAT3 and Smad3.

Comparison of the extraperitoneal and transperitoneal routes for permanent colostomy: a meta-analysis with RCTs and systematic review.

AIM: To assess the efficacy of extraperitoneal colostomy (EPC) in preventing stoma-related complications. BACKGROUND: Transperitoneal colostomy (TPC) is a widely used surgical approach. However, TPCs have been reported to have increased risks of stoma-related complications, such as parastomal hernias, stomal retraction, and stomal prolapse. The purpose of EPC is to reduce these complications. However, there is still a lack of evidence-based studies. MATERIALS AND METHODS: MEDLINE, EMBASE, Web of Science, Scopus, MOOSE, PubMed, Google Scholar, Baidu Scholar, and the Cochrane Library were searched to conduct a systematic review and meta-analysis with RCTs. The meta-analysis was performed with RevMan 5.4 software. RESULTS: This study included 5 eligible RCTs. Compared with the TPC group, the EPC group had lower incidence rates of parastomal hernias (RR, 0.14; 95% CI, 0.04-0.52, P = 0.003, I2 = 0%) and stomatal prolapse (RR, 0.27; 95% CI, 0.08-0.95, P = 0.04, I2 = 0%), but a higher rate of defecation sensation (RR, 3.51; 95% CI, 2.47-5.0, P < 0.00001, I2 = 37%). No statistically significant differences were observed in stoma retraction, colostomy construction time, stoma ischemia, or stoma necrosis. CONCLUSION: Extraperitoneal colostomies are associated with lower rates of postoperative complications than transperitoneal colostomies. A randomized controlled trial meta-analysis found that permanent colostomies after abdominoperineal resection resulted in better outcomes.

Celastrol alleviates metabolic disturbance in high-fat diet-induced obese mice through increasing energy expenditure by ameliorating metabolic inflammation.

Celastrol, a natural triterpene, has been shown to treat obesity and its related metabolic disorders. In this study, we first assessed the relationship between the antiobesity effects of celastrol and its antiinflammatory activities. Our results showed that celastrol can reduce weight gain, ameliorate glucose intolerance, insulin resistance, and dyslipidemia without affecting food intake in high-fat diet-induced obese mice. A CLAMS was used to clarify the improvement of metabolic profiles was attribute to increased adipose thermogenesis after celastrol treatment. Further studies found that celastrol decreased the infiltration of macrophage as well as its inflammatory products (IL-1ß, IL-18, MCP-1α, and TNF-α) in liver and adipose tissues, which also displayed an obvious inhibition of TLR3/NLRP3 inflammasome molecules. This study demonstrated that celastrol could be a potential drug for treating metabolic disorders, the underlying mechanism is related to ameliorating metabolic inflammation, thus increasing body energy expenditure.

Notch signaling in bone marrow-derived FSP-1 cells initiates neointima formation in arteriovenous fistulas.

Neointima formation is a major contributor to arteriovenous fistula (AVF) failure. We have previously shown that activation of the Notch signaling pathway contributes to neointima formation by promoting the migration of vascular smooth muscle cells (VSMCs) into the venous anastomosis. In the current study we investigated the mechanisms underlying the dedifferentiation and migration of VSMCs, and in particular the role of bone marrow-derived fibroblast specific protein 1 (FSP-1)+ cells, another cell type found in models of vascular injury. Using VSMC-specific reporter mice, we found that most of the VSMCs participating in AVF neointima formation originated from dedifferentiated VSMCs. We also observed infiltration of bone marrow-derived FSP-1+ cells into the arterial anastomosis where they could interact with VSMCs. In vitro, conditioned media from FSP-1+ cells stimulated VSMC proliferation and phenotype switching. Activated Notch signaling transformed FSP-1+ cells into type I macrophages and stimulated secretion of cytokines and growth factors. Pretreatment with a Notch inhibitor or knockout of the canonical downstream factor RBP-Jκ in bone marrow-derived FSP1+ cells decreased FSP1+ cell infiltration into murine AVFs, attenuating VSMC dedifferentiation and neointima formation. Our results suggest that targeting Notch signaling could provide a new therapeutic strategy to improve AVF patency.

Reduced Expression of Glutathione S-Transferase α 4 Promotes Vascular Neointimal Hyperplasia in CKD.

Neointima formation is the leading cause of arteriovenous fistula (AVF) failure. We have shown that CKD accelerates this process by transforming the vascular smooth muscle cells (SMCs) lining the AVF from a contractile to the synthetic phenotype. However, the underlying mechanisms affecting this transformation are not clear. Previous studies have shown that the α-class glutathione transferase isozymes have an important role in regulating 4-hydroxynonenal (4-HNE)-mediated proliferative signaling of cells. Here, using both the loss- and gain-of-function approaches, we investigated the role of glutathione S-transferase α4 (GSTA4) in modulating cellular 4-HNE levels for the transformation and proliferation of SMCs. Compared with non-CKD controls, mice with CKD had downregulated expression of GSTA4 at the mRNA and protein levels, with concomitant increase in 4-HNE in arteries and veins. This effect was associated with upregulated phosphorylation of MAPK signaling pathway proteins in proliferating SMCs. Overexpressing GSTA4 blocked 4-HNE-induced SMC proliferation. Additionally, inhibitors of MAPK signaling inhibited the 4-HNE-induced responses. Compared with wild-type mice, mice lacking GSTA4 exhibited increased CKD-induced neointima formation in AVF. Transient expression of an activated form of GSTA4, achieved using a combined Tet-On/Cre induction system in mice, lowered levels of 4-HNE and reduced the proliferation of SMCs. Together, these results demonstrate the critical role of GSTA4 in blocking CKD-induced neointima formation and AVF failure.

Wu-Mei-wan protects pancreatic ß cells by inhibiting NLRP3 Inflammasome activation in diabetic mice.

BACKGROUND: Wu-Mei-Wan (WMW) is a traditional Chinese herbal formulation that is clinically prescribed to treat diabetes mellitus in China. WMW has been shown to alleviate damage in pancreatic ß cells, but the underlying mechanism remains unclear. This study aims to explore how WMW plays a protective role in pancreatic islets. METHODS: Drug testing and mechanism analyses were performed on mice treated with three concentrations of WMW (4800, 9600, and 19,200 mg/kg/bw) for four consecutive weeks. Blood was collected from both db/db and wild-type mice to determine fasting blood glucose (FBG) and serum insulin levels. The expression of proteins related to apoptosis, cysteinyl aspartate-specific proteinase 12 (caspase-12) and B-cell leukemia 2 (Bcl-2), was measured by western blot. Interleukin-1ß (IL-1ß), interleukin-18 (IL-18), monocyte chemoattractant protein-1α (MCP-1α), and tumor necrosis factor-α (TNF-α) in the pancreas were tested with enzyme-linked immunosorbent assay (ELISA). Immunohistochemistry staining of F4/80 was performed to measure the pancreatic infiltration of macrophages. Western blot and immunofluorescence staining of the NLRP3 inflammasome were used to measure the expression of proteins related to apoptosis and inflammation. RESULTS: WMW dose-dependently reduced FBG and promoted serum insulin secretion in db/db mice compared to the wild-type controls. WMW protected pancreatic ß cells with a pattern of decreasing caspase-12 and increasing Bcl-2 expression. WMW also reversed the upregulated production of IL-1ß, IL-18, MCP-1α, and macrophage-specific surface glycoprotein F4/80 in diabetic mice. In addition, the protein expression levels of NLRP3 inflammasome components NLRP3, ASC, and caspase-1 (P20) were higher in db/db mice than in wild-type controls. CONCLUSIONS: WMW inhibits the activation of the NLRP3 inflammasome to protect pancreatic ß cells and prevent type 2 diabetes mellitus development.

Protective role of down-regulated microRNA-31 on intestinal barrier dysfunction through inhibition of NF-κB/HIF-1α pathway by binding to HMOX1 in rats with sepsis.

BACKGROUND: Intestinal barrier dysfunction is a significant clinical problem, commonly developing in a variety of acute or chronic pathological conditions. Herein, we evaluate the effect of microRNA-31 (miR-31) on intestinal barrier dysfunction through NF-κB/HIF-1α pathway by targeting HMOX1 in rats with sepsis. METHODS: Male Sprague-Dawley rats were collected and divided into the sham group, and the cecum ligation and perforation group which was subdivided after CACO-2 cell transfection of different mimic, inhibitor, or siRNA. Levels of serum D-lactic acid, diamine oxidase and fluorescence isothiocyanate dextran, FITC-DX concentration, and bacterial translocation were detected. Superoxidedismutase (SOD) activity and malondialdehyde (MDA) content were evaluated using the colorimetric method and an automatic microplate reader, respectively. Additionally, the levels of tumor necrosis factor, interleukin (IL)-6, and IL-10 were tested using enzyme-linked immunosorbent assay. The expression of miR-31, HMOX1, NF-κB, HIF-1α, IκB, ZO-1 and Occludin were assessed by reverse transcription quantitative polymerase chain reaction and Western blot analysis. RESULTS: Inhibition of miR-31 decreased intestinal mucosal permeability and intestinal barrier function. The increased levels of miR-31 could cause oxidative damage and affect the expression of inflammatory factors in intestinal tissue of rats. HMOX1 was confirmed as a target gene of miR-31. MiR-31 affected intestinal mucosal permeability and intestinal barrier function, as well as oxidative damage and inflammation level by regulating HMOX1. Down-regulation of miR-31 inhibited NF-κB/HIF-1α pathway related genes by regulating HMOX1 expression. Furthermore, inhibition of miR-31 increased survival rates of rats. CONCLUSION: Overall, the current study found that inhibition of miR-31 protects against intestinal barrier dysfunction through suppression of the NF-κB/HIF-1α pathway by targeting HMOX1 in rats with sepsis.

Yap/Taz Deletion in Gli+ Cell-Derived Myofibroblasts Attenuates Fibrosis.

In damaged kidneys, increased extracellular matrix (ECM) and tissue stiffness stimulate kidney fibrosis through incompletely characterized molecular mechanisms. The transcriptional coactivators yes-associated protein (Yap) and transcriptional coactivator with PDZ-binding motif (Taz) function as mechanosensors in cancer cells and have been implicated in the regulation of myofibroblasts in the kidney. We hypothesized that the development of kidney fibrosis depends on Yap-induced activation and proliferation of kidney fibroblasts. In mice, Yap expression increased in renal fibroblasts after unilateral ureteral obstruction (UUO), in association with worsening of interstitial fibrosis. In cultured fibroblasts, inhibition of Yap/Taz signaling blocked TGF-ß1-induced fibroblast-to-myofibroblast transformation and ECM production, whereas constitutive activation of Yap promoted fibroblast transformation and ECM production even in the absence of TGF-ß1. Moreover, in the absence of TGF-ß1, fibroblasts seeded on a stiffened ECM transformed into myofibroblasts in a process dependent on the activation of Yap. In mice with UUO, the Yap inhibitor verteporfin reduced interstitial fibrosis. Furthermore, Gli1+ cell-specific knockout of Yap/Taz in mice suppressed UUO-induced ECM deposition, myofibroblast accumulation, and interstitial fibrosis. In a UUO-release model, induction of Gli1+ cell-specific Yap/Taz knockout partially reversed the development of interstitial fibrosis. Thus, in the kidney, Yap is a tissue mechanosensor that can be activated by ECM and transforms fibroblasts into myofibroblasts; the interaction of Yap/Taz and ECM forms a feed-forward loop resulting in kidney fibrosis. Identifying mechanisms that interrupt this profibrotic cycle could lead to the development of anti-fibrosis therapy.

Modified Transsubxiphoid Thoracoscopic Extended Thymectomy in Patients with Myasthenia Gravis.

We developed a new minimally invasive thoracoscopic technique of extended thymectomy for myasthenia gravis by combining a subxiphoid incision with dual costal margin incisions. In our experience of 31 consecutive cases, this procedure provides a good operative view in the neck region and makes verification of the bilateral phrenic nerves easy. All the patients recovered smoothly with less trauma, less bleeding, less complication, and good cosmetic results. This modified transsubxiphoid approach is a satisfactory procedure for performing extended thymectomy in patients with myasthenia gravis.

Serum Glucocorticoid-Regulated Kinase 1 Blocks CKD-Induced Muscle Wasting Via Inactivation of FoxO3a and Smad2/3.

Muscle proteolysis in CKD is stimulated when the ubiquitin-proteasome system is activated. Serum glucocorticoid-regulated kinase 1 (SGK-1) is involved in skeletal muscle homeostasis, but the role of this protein in CKD-induced muscle wasting is unknown. We found that, compared with muscles from healthy controls, muscles from patients and mice with CKD express low levels of SGK-1. In mice, SGK-1-knockout (SGK-1-KO) induced muscle loss that correlated with increased expression of ubiquitin E3 ligases known to facilitate protein degradation by the ubiquitin-proteasome, and CKD substantially aggravated this response. SGK-1-KO also altered the phosphorylation levels of transcription factors FoxO3a and Smad2/3. In C2C12 muscle cells, expression of dominant negative FoxO3a or knockdown of Smad2/3 suppressed the upregulation of E3 ligases induced by loss of SGK-1. Additionally, SGK-1 overexpression increased the level of phosphorylated N-myc downstream-regulated gene 1 protein, which directly interacted with and suppressed the phosphorylation of Smad2/3. Overexpression of SGK-1 in wild-type mice with CKD had similar effects on the phosphorylation of FoxO3a and Smad2/3 and prevented CKD-induced muscle atrophy. Finally, mechanical stretch of C2C12 muscle cells or treadmill running of wild-type mice with CKD stimulated SGK-1 production, and treadmill running inhibited proteolysis in muscle. These protective responses were absent in SGK-1-KO mice. Thus, SGK-1 could be a mechanical sensor that mediates exercise-induced improvement in muscle wasting stimulated by CKD.

Jia-Wei-Jiao-Tai-Wan ameliorates type 2 diabetes by improving ß cell function and reducing insulin resistance in diabetic rats.

BACKGROUND: Jia-Wei-Jiao-Tai-Wan (JWJTW), composed of Jiao-Tai-Wan (Cinnamomum cassia and Rhizoma coptidis) and other antidiabetic herbs, including Astragalus membranaceus, Herba Gynostemmatis, Radix Puerariae Lobatae, Folium Mori and Semen Trigonellae, is widely used to treat diabetes and has demonstrated a curative effect in the clinic, but the potential mechanism is unknown. This study aimed to explore the effects of JWJTW on diabetic rats and to clarify the underlying mechanism. METHODS: JWJTW was prepared, and the main components contained in the formula were identified by high-performance liquid chromatography (HPLC) fingerprint analysis. Diabetic rats induced by streptozotocin (STZ) and a high-sucrose-high-fat diet were treated with two concentrations of JWJTW (1.025 and 2.05 g/kg/d) for 100 days. The oral glucose tolerance test (OGTT), insulin release test (IRT) and insulin tolerance test (ITT) were performed to measure the glycometabolism of the diabetic rats at the end of the treatment period. Blood was collected to determine the serum lipid levels of the diabetic rats. Nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) were detected in pancreas homogenates to analyze the oxidative stress in the pancreata of diabetic rats, and the expression levels of pancreatic and duodenal homeobox 1 (PDX-1) and insulin in the pancreas were tested by Western blot to measure pancreatic islet function. In addition, Western blots were used to measure the expression of proteins related to the insulin signaling pathway in skeletal muscle of the diabetic rats. RESULTS: The results showed that the administration of JWJTW could ameliorate impairments in glucose tolerance, insulin release function and insulin tolerance in diabetic rats. JWJTW could also dose-dependently reduce serum lipid levels in diabetic rats. JWJTW restrained oxidative stress by decreasing the expression of NO and MDA and increasing the expression of SOD and GSH-px. JWJTW improved the function of pancreatic ß cells by increasing PDX-1 and insulin expression. In addition, JWJTW restored the impaired insulin signaling; upregulated phospho-insulin receptor (pInsR) expression, insulin receptor substrate (IRS) tyrosine phosphorylation, phosphatidylinositol 3-kinase (PI3K) (p85), and glucose transporter 4 (GLUT4) expression; and downregulated the serine phosphorylation of IRS. CONCLUSIONS: This study suggests that JWJTW can ameliorate type 2 diabetes by improving ß cell function and reducing insulin resistance in diabetic rats.

Protective role of insulin-like growth factor-1 receptor in endothelial cells against unilateral ureteral obstruction-induced renal fibrosis.

Insulin-like growth factor-1 receptor (IGF-1R) can regulate vascular homeostasis and endothelial function. We studied the role of IGF-1R in oxidative stress-induced endothelial dysfunction. Unilateral ureteral obstruction (UUO) was performed in wild-type (WT) mice and mice with endothelial cell (EC)-specific IGF-1R knockout (KO). After UUO in endothelial IGF-1R KO mice, endothelial barrier dysfunction was more severe than in WT mice, as seen by increased inflammatory cell infiltration and vascular endothelial (VE)-cadherin phosphorylation. UUO in endothelial IGF-1R KO mice increased interstitial fibroblast accumulation and enhanced extracellular protein deposition as compared with the WT mice. Endothelial barrier function measured by transendothelial migration in response to hydrogen peroxide (H2O2) was impaired in ECs. Silencing IGF-1R enhanced the influence of H2O2 in disrupting the VE-protein tyrosine phosphatase/VE-cadherin interaction. Overexpression of IGF-1R suppressed H2O2-induced endothelial barrier dysfunction. Furthermore, by using the piggyBac transposon system, we expressed IGF-1R in VE cells in mice. The expression of IGF-1R in ECs also suppressed the inflammatory cell infiltration and renal fibrosis induced by UUO. IGF-1R KO in the VE-cadherin lineage of bone marrow cells had no significant effect on the UUO-induced fibrosis, as compared with control mice. Our results indicate that IGF-1R in the endothelium maintains the endothelial barrier function by stabilization of the VE-protein tyrosine phosphatase/VE-cadherin complex. Decreased expression of IGF-1R impairs endothelial function and increases the fibrosis of kidney disease.

Blocking Notch in endothelial cells prevents arteriovenous fistula failure despite CKD.

Neointima formation causes the failure of 60% of arteriovenous fistulas (AVFs) within 2 years. Neointima-forming mechanisms are controversial but possibly linked to excess proinflammatory responses and dysregulated Notch signaling. To identify how AVFs fail, we anastomosed the carotid artery to the internal jugular vein in normal and uremic mice and compared these findings with those in failed AVFs from patients with ESRD. Endothelial cells (ECs) of AVFs in uremic mice or patients expressed mesenchymal markers (FSP-1 and/or α-SMA) and exhibited increased expression and nuclear localization of Notch intracellular domain compared with ECs of AVFs in pair-fed control mice. Furthermore, expression of VE-Cadherin decreased, whereas expression of Notch1 and -4, Notch ligands, the downstream transcription factor of Notch, RBP-Jκ, and Notch target genes increased in ECs of AVFs in uremic mice. In cultured ECs, ectopic expression of Notch ligand or treatment with TGF-ß1 triggered the expression of mesenchymal markers and induced endothelial cell barrier dysfunction, both of which were blocked by Notch inhibition or RBP-Jκ knockout. Furthermore, Notch-induced defects in barrier function, invasion of inflammatory cells, and neointima formation were suppressed in mice with heterozygous knockdown of endothelial-specific RBP-Jκ. These results suggest that increased TGF-ß1, a complication of uremia, activates Notch in endothelial cells of AVFs, leading to accelerated neointima formation and AVF failure. Suppression of Notch activation could be a strategy for improving AFV function in uremia.

N-Acetylcysteine Attenuates Sepsis-Induced Muscle Atrophy by Downregulating Endoplasmic Reticulum Stress.

(1) Background: Sepsis-induced muscle atrophy is characterized by a loss of muscle mass and function which leads to decreased quality of life and worsens the long-term prognosis of patients. N-acetylcysteine (NAC) has powerful antioxidant and anti-inflammatory properties, and it relieves muscle wasting caused by several diseases, whereas its effect on sepsis-induced muscle atrophy has not been reported. The present study investigated the effect of NAC on sepsis-induced muscle atrophy and its possible mechanisms. (2) Methods: The effect of NAC on sepsis-induced muscle atrophy was assessed in vivo and in vitro using cecal ligation and puncture-operated (CLP) C57BL/6 mice and LPS-treated C2C12 myotubes. We used immunofluorescence staining to analyze changes in the cross-sectional area (CSA) of myofibers in mice and the myotube diameter of C2C12. Protein expressions were analyzed by Western blotting. (3) Results: In the septic mice, the atrophic response manifested as a reduction in skeletal muscle weight and myofiber cross-sectional area, which is mediated by muscle-specific ubiquitin ligases-muscle atrophy F-box (MAFbx)/Atrogin-1 and muscle ring finger 1 (MuRF1). NAC alleviated sepsis-induced skeletal muscle wasting and LPS-induced C2C12 myotube atrophy. Meanwhile, NAC inhibited the sepsis-induced activation of the endoplasmic reticulum (ER) stress signaling pathway. Furthermore, using 4-Phenylbutyric acid (4-PBA) to inhibit ER stress in LPS-treated C2C12 myotubes could partly abrogate the anti-muscle-atrophy effect of NAC. Finally, NAC alleviated myotube atrophy induced by the ER stress agonist Thapsigargin (Thap). (4) Conclusions: NAC can attenuate sepsis-induced muscle atrophy, which may be related to downregulating ER stress.

Peroxiredoxin 6 Protects Pulmonary Epithelial Cells From Cigarette-related Ferroptosis in Chronic Obstructive Pulmonary Disease.

Peroxiredoxin 6 (PRDX6) has a protective effect on pulmonary epithelial cells against cigarette smoke (CS)-induced ferroptosis. This study investigates the role of PRDX6 in the development of chronic obstructive pulmonary disease (COPD) and its possibility as a target. We observed that PRDX6 was downregulated in lung tissues of COPD patients and in CS-stimulated cells. The degradation of PRDX6 could be through the lysosomal pathway. PRDX6 deficiency exacerbated pulmonary inflammation and mucus hypersecretion in vivo. Overexpression of PRDX6 in Beas-2B cells ameliorated CS-induced cell death and inflammation, suggesting its protective role against CS-induced damage. Furthermore, PRDX6 deficiency promoted ferroptosis by adding the content of iron and reactive oxygen species, while iron chelation with deferoxamine mitigated CS-induced ferroptosis, cell death, and inflammatory infiltration both in vitro and in vivo. The critical role of PRDX6 in regulating ferroptosis suggests that targeting PRDX6 or iron metabolism may represent a promising strategy for COPD treatment.

Injectable Self-Expanding/Self-Propelling Hydrogel Adhesive with Procoagulant Activity and Rapid Gelation for Lethal Massive Hemorrhage Management.

Developing hydrogels that can quickly reach deep bleeding sites, adhere to wounds, and expand to stop lethal and/or noncompressible bleeding in civil and battlefield environments remains a challenge. Herein, an injectable, antibacterial, self-expanding, and self-propelling hydrogel bioadhesive with procoagulant activity and rapid gelation is reported. This hydrogel combines spontaneous gas foaming and rapid Schiff base crosslinking for lethal massive hemorrhage. Hydrogels have rapid gelation and expansion rate, high self-expanding ratio, excellent antibacterial activity, antioxidant efficiency, and tissue adhesion capacity. In addition, hydrogels have good cytocompatibility, procoagulant ability, and higher blood cell/platelet adhesion activity than commercial combat gauze and gelatin sponge. The optimized hydrogel (OD-C/QGQL-A30) exhibits better hemostatic ability than combat gauze and gelatin sponge in rat liver and femoral artery bleeding models, rabbit volumetric liver loss massive bleeding models with/without anticoagulant, and rabbit liver and kidney incision bleeding models with bleeding site not visible. Especially, OD-C/QGQL-A30 rapidly stops the bleedings from pelvic area of rabbit, and swine subclavian artery vein transection. Furthermore, OD-C/QGQL-A30 has biodegradability and biocompatibility, and accelerates Methicillin-resistant S. aureus (MRSA)-infected skin wound healing. This injectable, antibacterial, self-expanding, and self-propelling hydrogel opens up a new avenue to develop hemostats for lethal massive bleeding, abdominal organ bleeding, and bleeding from coagulation lesions.

Iron Overload-Dependent Ferroptosis Aggravates LPS-Induced Acute Lung Injury by Impairing Mitochondrial Function.

Ferroptosis is a newly proposed form of programmed cell death that is iron-dependent and closely linked to oxidative stress. Its specific morphological changes include shrunken mitochondria, increased density of mitochondrial membrane, and rupture or disappearance of mitochondrial cristae. The main mechanism of ferroptosis involves excessive free iron reacting with membrane phospholipids, known as the Fenton reaction, resulting in lipid peroxidation. However, the role of iron in acute lung injury (ALI) remains largely unknown. In this study, LPS was instilled into the airway to induce ALI in mice. We observed a significant increase in iron concentration during ALI, accompanied by elevated levels of lipid peroxidation markers such as malonaldehyde (MDA) and 4-hydroxynonenal (4-HNE). Treatment with the iron chelator deferoxamine (DFO) or ferroptosis inhibitor ferrostatin-1 (Fer-1) reversed lipid peroxidation and significantly attenuates lung injury. Similarly, DFO or Fer-1 treatment improved the cell survival significantly in vitro. These results demonstrated that ferroptosis occurs during ALI and that targeting ferroptosis is an effective treatment strategy. Interestingly, we found that the increased iron was primarily concentrated in mitochondria and DFO treatment effectively restored normal mitochondria morphology. To further confirm the damaging effect of iron on mitochondria, we performed mitochondrial stress tests in vitro, which revealed that iron stimulation led to mitochondrial dysfunction, characterized by impaired basal respiratory capacity, ATP production capacity, and maximum respiratory capacity. MitoTEMPO, an antioxidant targeting mitochondria, exhibited superior efficacy in improving iron-induced mitochondrial dysfunction compared to the broad-spectrum antioxidant NAC. Treatment with MitoTEMPO more effectively alleviated ALI. In conclusion, ferroptosis contributes to the pathogenesis of ALI and aggravates ALI by impairing mitochondrial function.

Protective role of pretreatment with Anisodamine against sepsis-induced diaphragm atrophy via inhibiting JAK2/STAT3 pathway.

There is an increasing tendency for sepsis patients to suffer from diaphragm atrophy as well as mortality. Therefore, reducing diaphragm atrophy could benefit sepsis patients' prognoses. Studies have shown that Anisodamine (Anis) can exert antioxidant effects when blows occur. However, the role of Anisodamine in diaphragm atrophy in sepsis patients has not been reported. Therefore, this study investigated the antioxidant effect of Anisodamine in sepsis-induced diaphragm atrophy and its mechanism. We used cecal ligation aspiration (CLP) to establish a mouse septic mode and stimulated the C2C12 myotube model with lipopolysaccharide (LPS). After treatment with Anisodamine, we measured the mice's bodyweight, diaphragm weight, fiber cross-sectional area and the diameter of C2C12 myotubes. The malondialdehyde (MDA) levels in the diaphragm were detected using the oxidative stress kit. The expression of MuRF1, Atrogin1 and JAK2/STAT3 signaling pathway components in the diaphragm and C2C12 myotubes was measured by RT-qPCR and Western blot. The mean fluorescence intensity of ROS in C2C12 myotubes was measured by flow cytometry. Meanwhile, we also measured the levels of Drp1 and Cytochrome C (Cyt-C) in vivo and in vitro by Western blot. Our study revealed that Anisodamine alleviated the reduction in diaphragmatic mass and the loss of diaphragmatic fiber cross-sectional area and attenuated the atrophy of the C2C12 myotubes by inhibiting the expression of E3 ubiquitin ligases. In addition, we observed that Anisodamine inhibited the JAK2/STAT3 signaling pathway and protects mitochondrial function. In conclusion, Anisodamine alleviates sepsis-induced diaphragm atrophy, and the mechanism may be related to inhibiting the JAK2/STAT3 signaling pathway.

Effects of oral probiotics on inflammation and intestinal function in adult patients after appendectomy: Randomized controlled trial.

BACKGROUND: Appendectomy is an acute abdominal surgery that is often accompanied by severe abdominal inflammation. Oral probiotics are one of the postoperative treatments for rapid rehabilitation. However, there is a lack of prospective studies on this topic after appendectomy. AIM: To investigate whether the postoperative probiotics can modulate the inflammatory response and restore intestinal function in patients following appendectomy. METHODS: This was a prospective, randomized trial. A total of 60 emergency patients were randomly divided into a control group (n = 30) and a probiotic group (n = 30). Patients in the control group started to drink some water the first day after surgery, and those in the probiotic group were given water supplemented with Bacillus licheniformis capsules for 5 consecutive days postsurgery. The indices of inflammation and postoperative conditions were recorded, and the data were analyzed with RStudio 4.3.2 software. RESULTS: A total of 60 participants were included. Compared with those in the control group, the C-reactive protein (CRP), interleukin 6 and procalcitonin (PCT) levels were significantly lower in the probiotic group at 2 d after surgery (P = 2.224e-05, P = 0.037, and P = 0.002, respectively, all P < 0.05). This trend persisted at day 5 post-surgery, with CRP and PCT levels remaining significantly lower in the probiotic group (P = 0.001 and P = 0.043, both P < 0.05). Furthermore, probiotics resulted in a shorter time to first flatus and a greater percentage of gram-negative bacilli in the feces (P = 0.035, P = 0.028, both P < 0.05). CONCLUSION: Postoperative oral administration of probiotics may modulate the gut microbiota, benefit the recovery of the early inflammatory response, and subsequently enhance recovery after appendectomy.