Melatonin as an immunomodulator in CD19-targeting CAR-T cell therapy: managing cytokine release syndrome.

BACKGROUND: Chimeric antigen receptor CAR-T cell therapies have ushered in a new era of treatment for specific blood cancers, offering unparalleled efficacy in cases of treatment resistance or relapse. However, the emergence of cytokine release syndrome (CRS) as a side effect poses a challenge to the widespread application of CAR-T cell therapies. Melatonin, a natural hormone produced by the pineal gland known for its antioxidant and anti-inflammatory properties, has been explored for its potential immunomodulatory effects. Despite this, its specific role in mitigating CAR-T cell-induced CRS remains poorly understood. METHODS: In this study, our aim was to investigate the potential of melatonin as an immunomodulatory agent in the context of CD19-targeting CAR-T cell therapy and its impact on associated side effects. Using a mouse model, we evaluated the effects of melatonin on CAR-T cell-induced CRS and overall survival. Additionally, we assessed whether melatonin administration had any detrimental effects on the antitumor efficacy and persistence of CD19 CAR-T cells. RESULTS: Our findings demonstrate that melatonin effectively mitigated the severity of CAR-T cell-induced CRS in the mouse model, leading to improved overall survival outcomes. Remarkably, melatonin administration did not compromise the antitumor effectiveness or persistence of CD19 CAR-T cells, indicating its compatibility with therapeutic goals. These results suggest melatonin's potential as an immunomodulatory compound to alleviate CRS without compromising the therapeutic benefits of CAR-T cell therapy. CONCLUSION: The study's outcomes shed light on melatonin's promise as a valuable addition to the existing treatment protocols for CAR-T cell therapies. By attenuating CAR-T cell-induced CRS while preserving the therapeutic impact of CAR-T cells, melatonin offers a potential strategy for optimizing and refining the safety and efficacy profile of CAR-T cell therapy. This research contributes to the evolving understanding of how to harness immunomodulatory agents to enhance the clinical application of innovative cancer treatments.

TRAF3/STAT6 axis regulates macrophage polarization and tumor progression.

Converting tumor-associated macrophages (TAMs) from the M2 to the M1 phenotype is considered an effective strategy for cancer therapy. TRAF3 is known to regulate NF-κB signaling. However, the role of TRAF3 in TAM polarization has not yet been completely elucidated. Here, we found that ablation of TRAF3 increased M1 markers, iNOS, FGR and SLC4A7, while down-regulated M2 markers, CD206, CD36 and ABCC3, expression levels in macrophages. Moreover, TRAF3 deficiency enhanced LPS-induced M1 and abolished IL-4-induced macrophage polarization. Next, quantitative ubiquitomics assays demonstrated that among the quantitative 7618 ubiquitination modification sites on 2598 proteins, ubiquitination modification of IL-4 responding proteins was the most prominently reduced according to enrichment analysis. STAT6, a key factor of IL-4 responding protein, K450 and K129 residue ubiquitination levels were dramatically decreased in TRAF3-deficient macrophages. Ubiquitination assay and luciferase assay demonstrated that TRAF3 promotes STAT6 ubiquitination and transcriptional activity. Site mutation analysis revealed STAT6 K450 site ubiquitination played a vital role in TRAF3-mediated STAT6 activation. Finally, B16 melanoma mouse model demonstrated that myeloid TRAF3 deficiency suppressed tumor growth and lung metastasis in vivo. Taken together, TRAF3 plays a vital role in M2 polarization via regulating STAT6 K450 ubiquitination in macrophages.

Clinical guideline on magnetically controlled capsule gastroscopy (2021 edition).

With the development and generalization of endoscopic technology and screening, clinical application of magnetically controlled capsule gastroscopy (MCCG) has been increasing. In recent years, various types of MCCG are used globally. Therefore, establishing relevant guidelines on MCCG is of great significance. The current guidelines containing 23 statements were established based on clinical evidence and expert opinions, mainly focus on aspects including definition and diagnostic accuracy, application population, technical optimization, inspection process, and quality control of MCCG. The level of evidence and strength of recommendations were evaluated. The guidelines are expected to guide the standardized application and scientific innovation of MCCG for the reference of clinicians.

Design, synthesis and evaluation of novel curcumin analog as potential anti-lung cancer agent.

Curcumin is a polyphenolic compound derived from the plant turmeric and the structural instability of which limits its further clinical applications. In this study, 11 curcumin analogs with more stable scaffold were prepared and evaluated. The results indicated that the optimal compound Y-11 exhibited the strongest antiproliferative activities against lung cancer cells including H460 and H1650. Further studies showed that Y-11 potentially inhibited hDHODH, induced cell cycle arrest and apoptosis as well as down-regulated crucial signal pathway protein expression in H1650 cells. In the conclusion, the newly designed curcumin analog Y-11 may be suitable for further development in lung cancer treatment.

Oncogenic TRIB2 interacts with and regulates PKM2 to promote aerobic glycolysis and lung cancer cell procession.

PKM2 is an important regulator of the aerobic glycolysis that plays a vital role in cancer cell metabolic reprogramming. In general, Trib2 is considered as a "pseudokinase", contributing to different kinds of cancer. However, the detailed roles of TRIB2 in regulating cancer metabolism by PKM2 remain unclear. This study demonstrated that TRIB2, not a "pseudokinase", has the kinase activity to directly phosphorylate PKM2 at serine 37 in cancer cells. The elevated pSer37-PKM2 would subsequently promote the PKM2 dimers to enter into nucleus and increase the expression of LDHA, GLUT1, and PTBP1. The aerobic glycolysis is then elevated to promote cancer cell proliferation and migration in TRIB2- or PKM2-overexpressed cultures. The glucose uptake and lactate production increased, but the ATP content decreased in TRIB2- or PKM2-treated cultures. Experiments of TRIB2-/- mice further supported that TRIB2 could regulate aerobic glycolysis by PKM2. Thus, these results reveal the new kinase activity of TRIB2 and its mechanism in cancer metabolism may be related to regulating PKM2 to promote lung cancer cell proliferation in vitro and in vivo, suggesting promising therapeutic targets for cancer therapy by controlling cancer metabolism.

[Bone tunnel positions in anterior cruciate ligament reconstruction evaluated by three-dimensional CT reconstruction based on Mimics software:modified transtibial versus anteromedial portal technique].

OBJECTIVE: To compare the femoral and tibial tunnel positions of anterior cruciate ligament reconstruction using the modified transtibial (MTT) technique and anteromedial (AM) portal technique. METHODS: Between January 2017 and September 2020, 78 patients with anterior cruciate ligament rupture underwent single-bundle reconstruction with the modified transtibial technique in 39 cases (group MTT) and through anteromedial approach in 39 cases (group AM). There were 25 males and 14 females in group MTT, with an average age of (37.0±2.3) years old; 27 males and 12 females in group AM, with an average age of (37.5±2.2) years old. CT scan of the affected knee was conducted one week after the surgery to measure and compare the femoral tunnels positioning (Fx, Fy), tibial tunnels positioning in the frontal plane(Tx1), tibial tunnels positioning in the sagittal plane (Ty1), and tibial tunnels positioning in the axial plane (Tx2, Ty2) in patients undergoing anterior cruciate ligament reconstruction through Mimics software. RESULTS: Three-dimensional CT reconstruction after the surgery showed that the average Fx and Fy were(25.2±2.1)% and (34.9±3.0)% respectively and the Tx1 and Ty1 were (45.5±3.3)% and (44.7± 3.0)% respectively, while the Tx2 and Ty2 were (47.0±3.0)% and (39.9±4.2)% respectively in group MTT. In group AM, the average Fx and Fy were (26.0±2.0)% and (36.1±3.9)% respectively and the Tx1 and Ty1 were (46.5±3.1)% and (45.6± 3.1)% respectively, while the Tx2 and Ty2 were (47.4±2.5)% and (39.6±3.9)% respectively. There were no statistically significant differences in the femoral and tibial tunnels between the two groups (P>0.05). Patients in both two groups obtained anatomic anterior cruciate ligament reconstruction. CONCLUSION: Both the MTT and AM technique can achieve good anatomical positioning of the femoral and tibial tunnels, without significant differences in the positioning of the bone tunnels.

Postconditioning with Calreticulin Attenuates Myocardial Ischemia/Reperfusion Injury and Improves Autophagic Flux.

BACKGROUND: Impaired autophagic flux contributes to cardiomyocyte death in ischemia/reperfusion (I/R) injury. Restoring the impaired autophagic flux by using agents may be a promising strategy that alleviates myocardial I/R injury. The present study aimed to evaluate the effect of exogenous calreticulin (CRT) postconditioning on impaired autophagic flux induced by hypoxia/reoxygenation (H/R) injury in H9c2 cells. METHODS: Rat myocardial I/R injury model was prepared. CRT postconditionging was fulfilled by an intraperitoneal injection of CRT (0.5 mg/kg body weight) 5 min before reperfusion. Hemodynamics, serum lactate dehydrogenase (LDH) activity and Cardiac troponin T (TnT) content, and infarct size were measured. The H/R injury model of H9c2 cells was prepared. CRT postconditioning was performed by adding 25 pg/mL CRT to the medium at the onset of reoxygenation. Cell death rate, lactate dehydrogenase (LDH) leakage, intracellular reactive oxygen species (ROS), and malondialdehyde (MDA) were assessed. Autophagic flux was monitored by mRFP-GFP-LC3 adenovirus infection. The number of autophagosomes and autolysosomes in cells were determined by counting the fluorescence dots. Western blot assay was used to determine the expression of autophagy-related proteins. RESULTS: CRT postconditionging improved cardiac function, reduced serum LDH activity and TnT content, and limited myocardial infarct size after myocardial I/R injury in rat. H/R induced H9c2 cells injury and autophagosomes accumulation in cells. CRT postconditioning attenuated H/R-induced cell death, LDH leakage, and the increase of intracellular ROS and MDA. Meanwhile, CRT postconditioning suppressed H/R-induced excessive formation of autophagosomes, as shown by a decrease of autophagosomes and the ratio of LC3-II/LC3-I, LC3-II, and Beclin1. It also improved H/R-induced impaired autophagosomes clearance, as shown by an increase of autolysosomes and the level of LAMP-2, and a decrease of the level of p62. CONCLUSION: These findings suggested that CRT postconditioning reduced myocardial I/R injury. CRT postconditioning also inhibited the excessive formation of autophagosomes, promoted the clearance of autophagosomes, and resorted the autophagic flux, consequently reduced the H/R injury in H9c2 cells.

Protective Effect of Nicotinamide Adenine Dinucleotide Phosphate on Renal Ischemia-Reperfusion Injury.

BACKGROUND/AIMS: Renal ischemia-reperfusion injury (IRI) is a common consequence of acute kidney injury. Nicotinamide adenine dinucleotide phosphate (NADPH), which is derived from the pentose phosphate pathway, is essential for the proper functioning of essential redox and antioxidant defense systems. Previous studies have indicated that NADPH is responsible for protecting the brain from ischemic injury. The goal of this study was to analyze the protective function of NADPH in renal IRI. METHODS: The IRI animal model was generated through a midline laparotomy surgery that clamped both sides of the renal pedicles for 40 min to induce renal ischemia. The in vitro model was generated by removing oxygen and glucose from human kidney epithelial cells (HK-2 cells), followed by reoxygenation to imitate IRI. Renal function and histopathological changes were observed and evaluated. Additionally, malondialdehyde and glutathione levels were determined in renal tissue homogenate as indicators of oxidative stress. ROS production in cells was determined by DHE staining. Protein biomarker expression was evaluated by western blot, apoptosis was analyzed by TUNEL staining, and p65 nuclear translocation was visualized by immunofluorescence. RESULTS: Our data indicated that NADPH safeguarded the kidneys from histological and functional damage, and significantly reduce cell injury along with preventing potential increases in blood urea nitrogen and creatinine levels. Furthermore, we observed that NADPH increased glutathione levels, while reducing levels of malondialdehyde and reactive oxygen species. Additionally, our results suggested that NADPH treatment may alleviate IRI-induced apoptosis and inflammation. CONCLUSION: NADPH treatment may protect against renal IRI and should be further developed as a new treatment for acute kidney injury.

Regulation and function of sphingosine kinase 2 in diseases.

Sphingosine kinase functions to phosphorylate sphingosine to sphingosine 1-phosphate (S1P) to keep balance in the metabolites of sphingolipids. There are two isoforms of sphingosine kinase, sphingosine kinase 1 (SphK1) and sphingosine kinase 2 (SphK2). Although SphK1 and SphK2 share high sequence similarity, SphK2 has distinct distribution, regulation and function. SphK2 is involved in the pathological processes of varieties of diseases including cancer, neurodegenerative disorders, stroke, cardiovascular diseases and inflammation. SphK2 may promote the proliferation of cancer cells and the progression of inflammation. The SphK2/S1P pathway is also involved in the pathogenesis of neurodegenerative disorders and stroke. S1P produced by SphK2 in the nucleus binds to HDACs, which then inhibits histone acetylation and regulates memory. The SphK2 pathway mediates platelet aggregation, thrombosis, cardioprotection and helps to ameliorate hepatic steatosis. This review focuses on the recent advances in research on SphK2 regulation and its potential roles in diseases, highlighting SphK2 may be a novel therapeutic strategy for diseases.

Single nucleotide polymorphisms rs701848 and rs2735343 in PTEN increases cancer risks in an Asian population.

We performed this meta-analysis to analyze the cancer risk to individuals carrying the rs701848 and rs2735343 single nucleotide polymorphisms (SNPs) in the phosphatase and tensin homolog (PTEN) gene. We searched the PubMed, EMBASE, Cochrane library and the national knowledge infrastructure of China (CNKI) databases and identified 18 eligible case-control studies with 5458 cases and 6003 controls for rs701848 as well as 5490 cases and 6209 controls for rs2735343. Our analyses demonstrated that cancer risk was associated with rs701848 in the recessive model (CC vs. CT+TT, OR=1.169, 95% CI: 1.061-1.288) and with rs2735343 in the dominant model (GC+CC vs. GG, OR=0.758, 95% CI: 0.590-0.972). Subgroup analysis showed that in Asian subjects, carrying the C allele of rs701848 or GG genotype of rs2735343 was associated with increased cancer risk. Moreover, Asian subjects carrying the TC/CC genotype or C allele of rs701848 were associated with increased risk of esophageal squamous cell cancer. This meta-analysis indicates that the PTEN rs701848 (CC) and rs2735343 (GG) polymorphisms are associated with increased cancer risk in Asian subjects.

[Role of Macrophages in Erythropoiesis -Review].

Terminal erythroid differentiation and its regulation occurs in the bone marrow specialized structure termed erythroblastic islands. The role of macrophages in erythropoiesis is closely related with the integrity of erythroblastic island, which is reliant on adhesive interactions between erythroid and macrophage cells. In regulating red blood cell homeostasis of adult, macrophages have 2 major roles, retaining erythroblast in bone marrow, controlling the final maturation of erythroblasts into reticulocytes and clearing old erythrocytes. Recent research demonstrated that body can affect erythropoiesis by regulating the function of macrophages in physiological or pathological conditions. This paper review focuses on the new advances of this aspect in recent years, including adhesion factor and regulatory factor between macrophage and red blood cells, role of macrophage in development of red blood cells, effect of macrophage on erythropoiesis in different conditiones and so on.

Sphingosine kinase 2 activates autophagy and protects neurons against ischemic injury through interaction with Bcl-2 via its putative BH3 domain.

Our previous findings suggest that sphingosine kinase 2 (SPK2) mediates ischemic tolerance and autophagy in cerebral preconditioning. The aim of this study was to determine by which mechanism SPK2 activates autophagy in neural cells. In both primary murine cortical neurons and HT22 hippocampal neuronal cells, overexpression of SPK2 increased LC3II and enhanced the autophagy flux. SPK2 overexpression protected cortical neurons against oxygen glucose deprivation (OGD) injury, as evidenced by improvement of neuronal morphology, increased cell viability and reduced lactate dehydrogenase release. The inhibition of autophagy effectively suppressed the neuroprotective effect of SPK2. SPK2 overexpression reduced the co-immunoprecipitation of Beclin-1 and Bcl-2, while Beclin-1 knockdown inhibited SPK2-induced autophagy. Both co-immunoprecipitation and GST pull-down analysis suggest that SPK2 directly interacts with Bcl-2. SPK2 might interact to Bcl-2 in the cytoplasm. Notably, an SPK2 mutant with L219A substitution in its putative BH3 domain was not able to activate autophagy. A Tat peptide fused to an 18-amino acid peptide encompassing the native, but not the L219A mutated BH3 domain of SPK2 activated autophagy in neural cells. The Tat-SPK2 peptide also protected neurons against OGD injury through autophagy activation. These results suggest that SPK2 interacts with Bcl-2 via its BH3 domain, thereby dissociating it from Beclin-1 and activating autophagy. The observation that Tat-SPK2 peptide designed from the BH3 domain of SPK2 activates autophagy and protects neural cells against OGD injury suggest that this structure may provide the basis for a novel class of therapeutic agents against ischemic stroke.

MiR-320a effectively suppresses lung adenocarcinoma cell proliferation and metastasis by regulating STAT3 signals.

MicroRNAs play important roles in tumorigenesis of various types of cancers. MiR-320a can inhibits cell proliferation of some cancers, but the biologic roles of miR-320a in lung cancer need to be further studied. Here, we investigated the roles of miR-320a in suppressing the proliferation of lung adenocarcinoma cells. MiR-320a treatment was found to effectively suppress LTEP-a-2 and A549 cell proliferation, and induce more apoptotic cells with irradiation treatment compared with control treatment. Our results also showed that miR-320a, as a novel miRNA, directly regulated signal transducer and activator of transcription 3 (STAT3) and its signals, such as Bcl-2, Bax, and Caspase 3. The siRNA-inhibited STAT3 levels further proved its roles in regulating STAT3 signals. Moreover, miR-320a treatment effectively suppressed cancer cell growth in mice xenografts compared with controls, and significantly inhibited cell migration in vitro and in vivo. Our findings collectively demonstrated that miR-320a, by directly regulating STAT3 signals, not only suppressed cell proliferation and metastasis, but also enhanced irradiation-induced apoptosis of adenocarcinomia cells.

Isolation, purification, characterization and immunostimulatory activity of polysaccharides derived from American ginseng.

In this study, crude American ginseng polysaccharide (AGPS) was extracted with hot water and preliminarily purified by using resin S-8 and Polyamide columns. Then, it was further purified and separated by DEAE-Sepharose CL-6B and Sepharose CL-6B chromatography, respectively. Five main fractions were obtained, named WPS-1, WPS-2, SPS-1, SPS-2 and SPS-3. Their homogeneities and structural characteristics were elucidated based on UV-vis spectroscopy, High Performance Gel Filtration Chromatography (HPGFC), Gas Chromatography (GC), Scanning Electron Microscopy (SEM), Infrared Spectrum (IR), and NMR Spectroscopy methods. Furthermore, the immunostimulatory effects of these fractions upon splenic lymphocyte proliferation, macrophage phagocytosis and nitric oxide (NO) production, were investigated in vitro. The results indicated that their stimulations could be ordered as SPS-3>SPS-1>CPS (crude polysaccharides)>WPS-1>WPS-2>SPS-2. Among them, SPS-3 showed more potent immunomodulatory activity and could be explored as a potential immunopotentiating agent for use in functional food or medicine.

MicroRNA-210 Plays a Critical Role in the Angiogenic Effect of Isoprenaline on Human Umbilical Vein Endothelial Cells via Regulation of Noncoding RNAs.

BACKGROUND: ß-adrenoceptors play a crucial regulatory role in blood vessel endothelial cells. Isoprenaline (ISO, a ß-adrenergic agonist) has been reported to promote angiogenesis through upregulation of vascular endothelial growth factor (VEGF) expression; however, the underlying mechanism remains to be investigated. It is widely accepted that certain noncoding RNAs, including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), can regulate endothelial cell behavior, including their involvement in angiogenesis. Therefore, we aimed to investigate whether noncoding RNAs participate in ISO-mediated angiogenesis using human umbilical vein endothelial cells (HUVECs). METHODS: We evaluated VEGF-A messenger RNA (mRNA) and protein levels in ISO-treated HUVECs by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. To establish whether noncoding RNAs are associated with ISO-mediated angiogenesis, we measured expression of the miRNAs miR-210, miR-21, and miR-1, as well as that of the lncRNAs growth arrest-specific transcript 5 (GAS5), maternally expressed 3 (MEG3), and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in HUVECs exposed to ISO. Furthermore, to ascertain its importance in ISO-mediated angiogenesis, we constructed the HUVECs with overexpressing miR-210 and detected the subsequent expression of VEGF-A and noncoding RNAs. All statistical analyses were performed using SPSS 16.0 software. Intergroup comparisons were carried out by one-way analysis of variance. RESULTS: VEGF-A mRNA levels were elevated in the ISO group (1.57 ± 0.09) compared to those in the control group (P < 0.01). Moreover, concentrations of VEGF-A in culture supernatants significantly differed between the control (113.00 ± 19.21 pg/ml) and ISO groups (287.00 ± 20.27 pg/ml; P< 0.01). Expression of miR-1, miR-21, and miR-210 was higher (3.89 ± 0.44, 2.87 ± 087, and 3.33 ± 1.31, respectively) in ISO-treated cells than that in controls (P < 0.01), whereas that of GAS5 and MEG3 (0.22 ± 0.10 and 0.58 ± 0.16, respectively) was lower as a result of ISO administration (P < 0.05). There was no significant difference in the expression of MALAT1 between the groups. Interestingly, miR-210 overexpression heightened the levels of VEGF-A and miR-21 (5.87 ± 1.24 and 2.74 ± 1.15, respectively; P< 0.01) and reduced those of GAS5 and MEG3 (0.19 ± 0.01 and 0.09 ± 0.05, respectively; P< 0.01). CONCLUSIONS: ISO-mediated angiogenesis was associated with altered expression of miR-210, miR-21, and the lncRNAs GAS5 and MEG3. The effects of miR-210 on the expression of VEGF-A and noncoding RNAs were similar to those of ISO, indicating that it might play an important role in ISO-mediated angiogenesis.

TIGAR contributes to ischemic tolerance induced by cerebral preconditioning through scavenging of reactive oxygen species and inhibition of apoptosis.

Previous study showed that TIGAR (TP53-induced glycolysis and apoptosis regulator) protected ischemic brain injury via enhancing pentose phosphate pathway (PPP) flux and preserving mitochondria function. This study was aimed to study the role of TIGAR in cerebral preconditioning. The ischemic preconditioning (IPC) and isoflurane preconditioning (ISO) models were established in primary cultured cortical neurons and in mice. Both IPC and ISO increased TIGAR expression in cortical neurons. Preconditioning might upregulate TIGAR through SP1 transcription factor. Lentivirus mediated knockdown of TIGAR significantly abolished the ischemic tolerance induced by IPC and ISO. ISO also increased TIGAR in mouse cortex and hippocampus and alleviated subsequent brain ischemia-reperfusion injury, while the ischemic tolerance induced by ISO was eliminated with TIGAR knockdown in mouse brain. ISO increased the production of NADPH and glutathione (GSH), and scavenged reactive oxygen species (ROS), while TIGAR knockdown decreased GSH and NADPH production and increased the level of ROS. Supplementation of ROS scavenger NAC and PPP product NADPH effectively rescue the neuronal injury caused by TIGAR deficiency. Notably, TIGAR knockdown inhibited ISO-induced anti-apoptotic effects in cortical neurons. These results suggest that TIGAR participates in the cerebral preconditioning through reduction of ROS and subsequent cell apoptosis.

Endoplasmic reticulum chaperone GRP78 is involved in autophagy activation induced by ischemic preconditioning in neural cells.

BACKGROUND: Our previous finding showed that brain ischemic preconditioning mediates neuroprotection through endoplasmic reticulum (ER) stress-induced autophagy. This study was aimed at exploring the role of ER chaperone GRP78 in IPC induced autophagy activation in neural cells. RESULTS: Ischemic preconditioning (IPC) and oxygen glucose deprivation (OGD) models were established in rat pheochromocytoma (PC12) cells and primary cultured murine cortical neurons. IPC exerted neuroprotection against subsequent OGD injury in both PC12 cells and primary cortical neurons. IPC increased GRP78 expression and activated autophagy, as evidenced by upregulated LC3 and Beclin1, increased autophagic flux and formation of autophagosomes. BAPTA(dibromo-1,2-bis(aminophenoxy)ethane N,N,N9,N9 - tetra acetic acid, 0.125-2 µM) and small interfering RNA targeted GRP78 abrogated IPC induced neuroprotection and decreased the expression of GRP78, LC3II/LC3I and Beclin1. In contrast, lentiviral vector mediated GRP78 overexpression (LV-GRP78) strengthened resistance of PC12 cells to OGD injury and increased LC3 and Beclin1 expression. Moreover, knockdown of GRP78 in stable GRP78 overexpressing PC12 cells abolished the upregulation of LC3II/LC3I. GRP78 might activate autophagy through AMPK - mTOR pathway. CONCLUSION: These results suggest that IPC- induced GRP78 upregulation is involved in autophagy activation, and hence exerts protection against ischemic injury in neural cells.

Panax quinquefolium saponin attenuates cardiomyocyte apoptosis and opening of the mitochondrial permeability transition pore in a rat model of ischemia/reperfusion.

AIMS: Opening of the mitochondrial permeability transition pore (mPTP) is a critical event during ischemia/reperfusion (I/R) injury. Recently, we showed that Panax quinquefolium saponin (PQS) alleviates apoptosis of cardiomyocytes by suppressing excessive endoplasmic reticulum stress (ERS) during I/R injury. Here, we hypothesized that this anti-apoptotic effect might be mediated through inhibition of mPTP and the mitochondrial apoptotic pathway. METHODS: Ninety-six healthy male Sprague-Dawley rats were randomly divided into sham, I/R, I/R+PQS (200 mg/kg/d), Cyclosporine A (CsA, 10 mg/kg), I/R+CsA (10 mg/kg), and I/R+PQS+CsA. I/R was modeled in rats by ligating the left anterior descending artery (LAD) for 30 min followed by 120 min of reperfusion. To evaluate the cardioprotective function of PQS, we measured hemodynamics, serum content of creatine kinase-MB (CK-MB), myocardial infarct size, and myocardial apoptotic index (AI). We investigated the underlying mechanism by examining changes in the mitochondrial ultrastructure and membrane potential (ΔΨm), dynamics of mPTP opening, expression of cleaved caspase-3, cleaved caspase-9 in the myocardium, Bcl-2 and Bax in the mitochondria versus cytosol, and translocation of cytochrome c. RESULTS: Administration of PQS to I/R rats significantly reduced serum CK-MB level, infarct size and AI. In addition, PQS protected the mitochondrial structure, markedly inhibited mPTP opening and ΔΨm depolarization, led to upregulation of Bcl-2 and downregulation of Bax in the mitochondria compared to the cytosol, and suppressed the expression of cleaved caspase-9 and cleaved caspase-3, as well as I/R induced translocation of cytochrome c to the cytoplasm. CONCLUSION: Our results show that PQS can alleviate apoptosis of cardiomyocytes during I/R injury, possibly due to repressed mitochondrial apoptotic pathway associated with the opening of mPTP induced by myocardial I/R injury.

Cytosolic calreticulin inhibits microwave radiation-induced microvascular endothelial cell injury through the integrin-focal adhesion kinase pathway.

OBJECTIVE: To determine the effects of cytosolic CRT on MR-induced MMEC injury, and the underlying mechanism. METHODS: MMECs were randomized into eight groups: control, AdCRT (infected with pAdCMV/V5-DEST-CRT adenovirus), stCRT (transfected with rCRT-siRNAs), Mock (transfected with scrambled siRNAs), MR (exposed to MR for six minutes), AdCRT + MR, stCRT + MR, and Mock + MR. The magnitude of cell injury were assessed by Annexin V-PI staining, LDH activity in culture medium, MMEC migration ability, ultrastructure and cytoskeletal stability. Subcellular colocalization of CRT and ConA or integrin were evaluated by immunocytochemistry. The mRNA and protein expression levels of target genes were examined by qRT-PCR and western blotting, respectively. RESULTS: MR-induced cytotoxicity was dose-dependent. Overexpression of cytosolic CRT suppressed MR injury, shown as decreased cell apoptosis, reduced LDH activity, enhanced cell migration capability, and maintenance of ultrastructure and cytoskeleton integrity. Conversely, CRT deficiency aggravated MR-induced injury. Exposure of AdCRT MMECs to MR promoted membrane translocation of CRT and the interaction of CRT-integrin-α. Correlation analysis revealed that integrin-α expression or FAK phosphorylation was positively associated with cytosolic CRT expression. CONCLUSIONS: Cytosolic CRT inhibits MR-induced MMEC injury through activation of the integrin-FAK pathway.

Neuron-glial communication mediated by TNF-α and glial activation in dorsal root ganglia in visceral inflammatory hypersensitivity.

Communication between neurons and glia in the dorsal root ganglia (DRG) and the central nervous system is critical for nociception. Both glial activation and proinflammatory cytokine induction underlie this communication. We investigated whether satellite glial cell (SGC) and tumor necrosis factor-α (TNF-α) activation in DRG participates in a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rat model of visceral hyperalgesia. In TNBS-treated rats, TNF-α expression increased in DRG and was colocalized to SGCs enveloping a given neuron. These SGCs were activated as visualized under electron microscopy: they had more elongated processes projecting into the connective tissue space and more gap junctions. When nerves attached to DRG (L6-S1) were stimulated with a series of electrical stimulations, TNF-α were released from DRG in TNBS-treated animals compared with controls. Using a current clamp, we noted that exogenous TNF-α (2.5 ng/ml) increased DRG neuron activity, and visceral pain behavioral responses were reversed by intrathecal administration of anti-TNF-α (10 µg·kg(-1)·day(-1)). Based on our findings, TNF-α and SGC activation in neuron-glial communication are critical in inflammatory visceral hyperalgesia.