Targeting EFHD2 inhibits interferon-γ signaling and ameliorates non-alcoholic steatohepatitis.

BACKGROUND & AIMS: The precise pathomechanisms underlying the development of non-alcoholic steatohepatitis (NASH, also known as metabolic dysfunction-associated steatohepatitis [MASH]) remain incompletely understood. In this study, we investigated the potential role of EF-hand domain family member D2 (EFHD2), a novel molecule specific to immune cells, in the pathogenesis of NASH. METHODS: Hepatic EFHD2 expression was characterized in patients with NASH and two diet-induced NASH mouse models. Single-cell RNA sequencing (scRNA-seq) and double-immunohistochemistry were employed to explore EFHD2 expression patterns in NASH livers. The effects of global and myeloid-specific EFHD2 deletion on NASH and NASH-related hepatocellular carcinoma were assessed. Molecular mechanisms underlying EFHD2 function were investigated, while chemical and genetic investigations were performed to assess its potential as a therapeutic target. RESULTS: EFHD2 expression was significantly elevated in hepatic macrophages/monocytes in both patients with NASH and mice. Deletion of EFHD2, either globally or specifically in myeloid cells, improved hepatic steatosis, reduced immune cell infiltration, inhibited lipid peroxidation-induced ferroptosis, and attenuated fibrosis in NASH. Additionally, it hindered the development of NASH-related hepatocellular carcinoma. Specifically, deletion of myeloid EFHD2 prevented the replacement of TIM4+ resident Kupffer cells by infiltrated monocytes and reversed the decreases in patrolling monocytes and CD4+/CD8+ T cell ratio in NASH. Mechanistically, our investigation revealed that EFHD2 in myeloid cells interacts with cytosolic YWHAZ (14-3-3ζ), facilitating the translocation of IFNγR2 (interferon-γ receptor-2) onto the plasma membrane. This interaction mediates interferon-γ signaling, which triggers immune and inflammatory responses in macrophages during NASH. Finally, a novel stapled α-helical peptide targeting EFHD2 was shown to be effective in protecting against NASH pathology in mice. CONCLUSION: Our study reveals a pivotal immunomodulatory and inflammatory role of EFHD2 in NASH, underscoring EFHD2 as a promising druggable target for NASH treatment. IMPACT AND IMPLICATIONS: Non-alcoholic steatohepatitis (NASH) represents an advanced stage of non-alcoholic fatty liver disease (NAFLD); however, not all patients with NAFLD progress to NASH. A key challenge is identifying the factors that trigger inflammation, which propels the transition from simple fatty liver to NASH. Our research pinpointed EFHD2 as a pivotal driver of NASH, orchestrating the over-activation of interferon-γ signaling within the liver during NASH progression. A stapled peptide designed to target EFHD2 exhibited therapeutic promise in NASH mice. These findings support the potential of EFHD2 as a therapeutic target in NASH.

Activation of α7 nicotinic acetylcholine receptors inhibits hepatic necroptosis and ameliorates acute liver injury in mice.

BACKGROUND: Acute liver injury (ALI) is a disease characterized by severe liver dysfunction, caused by significant infiltration of immune cells and extensive cell death with a high mortality. Previous studies demonstrated that the α7 nicotinic acetylcholine receptor (α7nAChR) played a crucial role in various liver diseases. The hypothesis of this study was that activating α7nAChR could alleviate ALI and investigate its possible mechanisms. METHODS: ALI was induced by intraperitoneal injection of lipopolysaccharide (LPS)/D-galactosamine (D-Gal) in wild type (WT), α7nAChR knockout (α7nAChR -/-) and Sting mutation (Stinggt/gt) mice in the presence or absence of a pharmacological selective α7nAChR agonist (PNU-282987). The effects of α7nAChR on hepatic injury, inflammatory response, mitochondrial damage, necroptosis and infiltration of immune cells during ALI were assessed. RESULTS: The expression of α7nAChR in liver tissue was increased in LPS/D-Gal induced ALI mice. Compared to the age-matched WT mice, α7nAChR deficiency decreased the survival rate, exacerbated the hepatic injury accompanied with enhanced inflammatory response and oxidative stress, and aggravated hepatic mitochondrial damage and necroptosis. Conversely, pharmacological activation of α7nAChR by PNU-282987 displayed the opposite trends. Furthermore, PNU-282987 significantly reduced the proportion of infiltrating monocyte-derived macrophages (CD45+CD11bhiF4/80int), M1 macrophages (CD45+CD11b+F4/80+CD86 hiCD163low), Ly6Chi monocytes (CD45+CD11b+MHCⅡ lowLy6C hi), but increased the resident Kupffer cells (CD45+CD11bintF4/80 hiTIM4 hi) in the damaged hepatic tissues caused by LPS/D-Gal. Interestingly, α7nAChR deficiency promoted the STING signaling pathway under LPS/D-Gal stimulation, while PNU-282987 treatment significantly prevented its activation. Finally, it was found that Sting mutation abolished the protective effects against hepatic injury by activating α7nAChR. CONCLUSIONS: Our study revealed that activating α7nAChR could protect against LPS/D-Gal induced ALI by inhibiting hepatic inflammation and necroptosis possibly via regulating immune cells infiltration and inhibiting STING signaling pathway.

Colchicine protects against the development of experimental abdominal aortic aneurysm.

Abdominal aortic aneurysm (AAA) is characterized by at least 1.5-fold enlargement of the infrarenal aorta, a ruptured AAA is life-threatening. Colchicine is a medicine used to treat gout and familial Mediterranean fever, and recently, it was approved to reduce the risk of cardiovascular events in adult patients with established atherosclerotic disease. With an AAA mice model created by treatment with porcine pancreatic elastase (PPE) and ß-aminopropionitrile (BAPN), this work was designed to explore whether colchicine could protect against the development of AAA. Here, we showed that colchicine could limit AAA formation, as evidenced by the decreased total aortic weight per body weight, AAA incidence, maximal abdominal aortic diameter and collagen deposition. We also found that colchicine could prevent the phenotypic switching of vascular smooth muscle cells from a contractile to synthetic state during AAA. In addition, it was demonstrated that colchicine was able to reduce vascular inflammation, oxidative stress, cell pyroptosis and immune cells infiltration to the aortic wall in the AAA mice model. Finally, it was proved that the protective action of colchicine against AAA formation was mainly mediated by preventing immune cells infiltration to the aortic wall. In summary, our findings demonstrated that colchicine could protect against the development of experimental AAA, providing a potential therapeutic strategy for AAA intervention in the clinic.

Ferroptosis inhibitor liproxstatin-1 alleviates metabolic dysfunction-associated fatty liver disease in mice: potential involvement of PANoptosis.

Ferroptosis is a new form of regulated cell death characterized by excessive iron accumulation and uncontrollable lipid peroxidation. The role of ferroptosis in metabolic dysfunction-associated fatty liver disease (MAFLD) is not fully elucidated. In this study we compared the therapeutic effects of ferroptosis inhibitor liproxstatin-1 (LPT1) and iron chelator deferiprone (DFP) in MAFLD mouse models. This model was established in mice by feeding a high-fat diet with 30% fructose in water (HFHF) for 16 weeks. The mice then received LPT1 (10 mg·kg-1·d-1, ip) or DFP (100 mg·kg-1·d-1, ig) for another 2 weeks. We showed that both LPT1 and DFP treatment blocked the ferroptosis markers ACSL4 and ALOX15 in MAFLD mice. Furthermore, LPT1 treatment significantly reduced the liver levels of triglycerides and cholesterol, lipid peroxidation markers 4-hydroxynonenal (4-HNE) and malondialdehyde (MDA), and ameliorated the expression of lipid synthesis/oxidation genes (Pparα, Scd1, Fasn, Hmgcr and Cpt1a), insulin resistance, mitochondrial ROS content and liver fibrosis. Importantly, LPT1 treatment potently inhibited hepatic apoptosis (Bax/Bcl-xL ratio and TUNEL+ cell number), pyroptosis (cleavages of Caspase-1 and GSDMD) and necroptosis (phosphorylation of MLKL). Moreover, LPT1 treatment markedly inhibited cleavages of PANoptosis-related caspase-8 and caspase-6 in MAFLD mouse liver. In an in vitro MAFLD model, treatment with LPT1 (100 nM) prevented cultured hepatocyte against cell death induced by pro-PANoptosis molecules (TNF-α, LPS and nigericin) upon lipid stress. On the contrary, DFP treatment only mildly attenuated hepatic inflammation but failed to alleviate lipid deposition, insulin resistance, apoptosis, pyroptosis and necroptosis in MAFLD mice. We conclude that ferroptosis inhibitor LPT1 protects against steatosis and steatohepatitis in MAFLD mice, which may involve regulation of PANoptosis, a coordinated cell death pathway that involves apoptosis, pyroptosis and necroptosis. These results suggest a potential link between ferroptosis and PANoptosis.

A therapeutic regimen of ceftazidime-avibactam for a critical patient receiving prolonged intermittent renal replacement therapy.

The present report firstly described a critically ill patient receiving a dosing regimen of ceftazidime-avibactam (CAZ-AVI) (1.875g q24h) to eliminate multidrug-resistant Klebsiella pneumoniae and a scheduled time for prolonged intermittent renal replacement therapy (PIRRT) every 48h (6h-session beginning 12h after the previous dosage on hemodialysis day). This dosing regimen for CAZ-AVI and a scheduled time for PIRRT allowed pharmacodynamic parameters of ceftazidime and avibactam to have little difference on hemodialysis and non-hemodialysis days so that we can maintain a relatively stable drug concentration. Our report highlighted not only the importance of dosing regimens in patients with PIRRT but also the significance of hemodialysis time points during the dosing interval. The innovative therapeutic plan proved to be suitable for patients infected with Klebsiella pneumoniae when on PIRRT according to the trough plasma concentrations of ceftazidime and avibactam which were maintained above the minimum inhibitory concentration during the dosing interval.

Exerkine fibronectin type-III domain-containing protein 5/irisin-enriched extracellular vesicles delay vascular ageing by increasing SIRT6 stability.

AIMS: Exercise confers protection against cardiovascular ageing, but the mechanisms remain largely unknown. This study sought to investigate the role of fibronectin type-III domain-containing protein 5 (FNDC5)/irisin, an exercise-associated hormone, in vascular ageing. Moreover, the existence of FNDC5/irisin in circulating extracellular vesicles (EVs) and their biological functions was explored. METHODS AND RESULTS: FNDC5/irisin was reduced in natural ageing, senescence, and angiotensin II (Ang II)-treated conditions. The deletion of FNDC5 shortened lifespan in mice. Additionally, FNDC5 deficiency aggravated vascular stiffness, senescence, oxidative stress, inflammation, and endothelial dysfunction in 24-month-old naturally aged and Ang II-treated mice. Conversely, treatment of recombinant irisin alleviated Ang II-induced vascular stiffness and senescence in mice and vascular smooth muscle cells. FNDC5 was triggered by exercise, while FNDC5 knockout abrogated exercise-induced protection against Ang II-induced vascular stiffness and senescence. Intriguingly, FNDC5 was detected in human and mouse blood-derived EVs, and exercise-induced FNDC5/irisin-enriched EVs showed potent anti-stiffness and anti-senescence effects in vivo and in vitro. Adeno-associated virus-mediated rescue of FNDC5 specifically in muscle but not liver in FNDC5 knockout mice, promoted the release of FNDC5/irisin-enriched EVs into circulation in response to exercise, which ameliorated vascular stiffness, senescence, and inflammation. Mechanistically, irisin activated DnaJb3/Hsp40 chaperone system to stabilize SIRT6 protein in an Hsp70-dependent manner. Finally, plasma irisin concentrations were positively associated with exercise time but negatively associated with arterial stiffness in a proof-of-concept human study. CONCLUSION: FNDC5/irisin-enriched EVs contribute to exercise-induced protection against vascular ageing. These findings indicate that the exerkine FNDC5/irisin may be a potential target for ageing-related vascular comorbidities.

Activating α7nAChR ameliorates abdominal aortic aneurysm through inhibiting pyroptosis mediated by NLRP3 inflammasome.

Abdominal aortic aneurysm (AAA) is defined as a dilated aorta in diameter at least 1.5 times of a normal aorta. Our previous studies found that activating α7 nicotinic acetylcholine receptor (α7nAChR) had a protective effect on vascular injury. This work was to investigate whether activating α7nAChR could influence AAA formation and explore its mechanisms. AAA models were established by angiotensin II (Ang II) infusion in ApoE-/- mice or in wild type and α7nAChR-/- mice. In vitro mouse aortic smooth muscle (MOVAS) cells were treated with tumor necrosis factor-α (TNF-α). PNU-282987 was chosen to activate α7nAChR. We found that cell pyroptosis effector GSDMD and NLRP3 inflammasome were activated in abdominal aorta, and inflammatory cytokines in serum were elevated in AAA models of ApoE-/- mice. Activating α7nAChR reduced maximal aortic diameters, preserved elastin integrity and decreased inflammatory responses in ApoE-/- mice with Ang II infusion. While α7nAChR-/- mice led to aggravated aortic injury and increased inflammatory cytokines with Ang II infusion when compared with wild type. Moreover, activating α7nAChR inhibited NLRP3/caspase-1/GSDMD pathway in AAA model of ApoE-/- mice, while α7nAChR deficiency promoted this pathway. In vitro, N-acetylcysteine (NAC) inhibited NLRP3 inflammasome activation and NLRP3 knockdown reduced GSDMD expression, in MOVAS cells treated with TNF-α. Furthermore, activating α7nAChR inhibited oxidative stress, reduced NLRP3/GSDMD expression, and decreased cell pyroptosis in MOVAS cells with TNF-α. In conclusion, our study found that activating α7nAChR retarded AAA through inhibiting pyroptosis mediated by NLRP3 inflammasome. These suggested that α7nAChR would be a potential pharmacological target for AAA.

[Abdominal Aortic Aneurysm:Pathological Mechanism and Animal Model].

Abdominal aortic aneurysm is defined as a dilated aorta with a diameter at least 1.5 times of the normal aorta.There is no effective drug for AAA.We summarized the high-risk factors,pathologic features,current therapies,and animal models in the pre-clinical study to gain comprehensive understanding of AAA.With this review,we aim to provide scientific support for the mining of therapeutic targets for AAA.

Effects of low-level mercury exposure on brain-derived neurotrophic factor in preschool children.

OBJECTIVES: Mercury (Hg), a ubiquitous heavy metal, could affect the neurodevelopment of the children, however, these associations are still equivocal. Brain derived neurotrophic factor (BDNF) plays an essential role in the central nervous system development in children. This study aimed to investigate the effects of low-level mercury exposure on serum BDNF levels and the influence of sex and dietary intake on these relationships in children. METHODS: In this cross-sectional study, a total of 541 pre-school children were recruited, the blood mercury concentrations and serum BDNF levels were measured. The background information on demographic characteristics and dietary habits of the children was collected through questionnaires. Multivariable linear models after adjustment for potential confounders were used to evaluate the associations between mercury exposure and levels of BDNF in children. RESULTS: The GMs of blood mercury concentrations and serum BDNF levels were 1.06 µg/L, 20.4 ng/mL, respectively. A significant positive association between blood mercury concentrations and serum BDNF levels was found. After stratification by sex, the blood mercury concentrations in children were positive associated with serum BDNF levels in girls but not in boys. However, these associations were attenuated when we further adjusted the children's dietary intake variables. CONCLUSIONS: Our findings suggest that low-levels of mercury exposure may have sex-specific effects on BDNF levels in young children and that dietary intake may be potential confounders in these relationships. However, further studies are warranted to investigate the role of BDNF in the effects of mercury on neurodevelopment.

microRNA-802 accelerates hepatocellular carcinoma growth by targeting RUNX3.

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. Prognosis is often unfavorable. In this study, the effects of microRNA-802 (miR-802) on HCC progression were assessed in vivo and in vitro. miR-802 was found to be significantly upregulated in HCC tumor tissue compared to paired adjacent nontumor tissue. In vitro, transfection with a miR-802 mimic accelerated SMMC-7721 cellular proliferation, increased accumulation of the cell-cycle S-phase cell populations, as well as cell migration. In vivo injection of a miR-802 agomir promoted HCC proliferation in nude mice. Targets of miR-802 were predicted by miRWalk, miRanda, RNA22, and Targetscan. By luciferase reporter assay RUNX3 was identified as a direct target of miR-802. As judged by western blot analysis, RUNX3 was upregulated when miR-802 was inhibited. These data demonstrate increased miR-802 expression in patients with HCC and that miR-802 overexpression promotes tumor cell growth, in a RUNX3-dependent manner.

Melatonin safeguards against fatty liver by antagonizing TRAFs-mediated ASK1 deubiquitination and stabilization in a ß-arrestin-1 dependent manner.

Melatonin has been previously shown to prevent nonalcoholic fatty liver disease (NAFLD), yet the underlying mechanisms are poorly understood. Here, we identified a previously unknown regulatory action of melatonin on apoptosis signal-regulating kinase 1 (ASK1) signaling pathway in the pathogenesis and development of NAFLD. Although melatonin administration did not alter food intake, it significantly alleviated fatty liver phenotypes, including the body weight gain, insulin resistance, hepatic lipid accumulation, steatohepatitis, and fibrosis in a high-fat diet (HFD)-induced NAFLD mouse model (in vivo). The protection of melatonin against NAFLD was not affected by inactivation of Kupffer cell in this model. In NAFLD mice liver, ASK1 signal cascade was substantially activated, evidence by the enhancement of total ASK1, phospho-ASK1, phospho-MKK3/6, phospho-p38, phospho-MKK4/7, and phospho-JNK. Melatonin treatment significantly suppressed the ASK1 upregulation and the phosphorylation of ASK1, MKK3/6, MKK4/7, p38, and JNK. Mechanistically, we found that lipid stress triggered the interaction between ASK1 and TNF receptor-associated factors (TRAFs), including TRAF1, TRAF2, and TRAF6, which resulted in ASK1 deubiquitination and thereby increased ASK1 protein stability. Melatonin did not alter ASK1 mRNA level; however, it activated a scaffold protein ß-arrestin-1 and enabled it to bind to ASK1, which antagonized the TRAFs-mediated ASK1 deubiquitination, and thus reduced ASK1 protein stability. Consistent with these findings, knockout of ß-arrestin-1 in mice partly abolished the protection of melatonin against NAFLD. Taken together, our results for the first time demonstrate that melatonin safeguards against NAFLD by eliminating ASK1 activation via inhibiting TRAFs-mediated ASK1 deubiquitination and stabilization in a ß-arrestin-1 dependent manner.

α7 Nicotinic Acetylcholine Receptor Relieves Angiotensin II-Induced Senescence in Vascular Smooth Muscle Cells by Raising Nicotinamide Adenine Dinucleotide-Dependent SIRT1 Activity.

OBJECTIVE: α7 nicotinic acetylcholine receptor (α7nAChR) is a subtype of nAChR and has been reported to be involved in hypertension end-organ damage. In this study, we tested the role of α7nAChR in angiotensin II (Ang II)-induced senescence of vascular smooth muscle cells (VSMCs). APPROACH AND RESULTS: Expression of α7nAChR was not influenced by Ang II. Ang II induced remarkable senescent phenotypes in rodent and human VSMCs, including increased senescence-associated ß-galactosidase activity, phosphorylation of H2A.X(Ser139), phosphorylation of Chk1(Ser317), reduced replication, and downregulation of proliferating cell nuclear antigen. Activation of α7nAChR with a selective agonist PNU-282987 blocked Ang II-induced senescence in cultured VSMCs. Moreover, PNU-282987 treatment attenuated the Ang II infusion-induced VSMC senescence in wild-type but not in α7nAChR(-/-) mice. PNU-282987 reduced the Ang II-enhanced reactive oxygen species, lipid peroxidation, and the expression of NADPH oxidase 1, NADPH oxidase 4, and p22(phox) in cultured VSMCs isolated from wild-type but not in α7nAChR(-/-) mice. Furthermore, PNU-282987 diminished Ang II-induced prosenescence signaling pathways, including p53, acetyl-p53, p21, and p16(INK4a). Finally, although α7nAChR activation by PNU-282987 did not affect the Ang II-induced downregulation of sirtuin 1 (SIRT1), it significantly increased intracellular NAD(+) levels, and thereby enhanced SIRT1 activity in an AMP-dependent protein kinase-independent manner. Depletion of SIRT1 by knockdown or SIRT1 inhibitor EX527 abrogated the antisenescence effect of α7nAChR against Ang II. CONCLUSIONS: Our results demonstrate that activation of α7nAChR alleviates Ang II-induced VSMC senescence through promoting NAD(+)-SIRT1 pathway, suggesting that α7nAChR may be a potential therapeutic target for the treatment of Ang II-associated vascular aging disorders.

Vagus Nerve Attenuates Hepatocyte Apoptosis upon Ischemia-Reperfusion via α7 Nicotinic Acetylcholine Receptor on Kupffer Cells in Mice.

BACKGROUND: Hepatic ischemia-reperfusion (HIR) injury is a complication of liver surgery. As much as 50% of hepatocytes undergo apoptosis within the first 24 h of reperfusion. The neurotransmitters of the vagus nerve can activate α7 nicotinic acetylcholine receptor (α7nAChR) on macrophages. The function of Kupffer cells (KCs) determines HIR injury. We hypothesize that the vagus nerve could attenuate HIR-induced hepatocyte apoptosis by activating α7nAChR on KCs. METHODS: Hepatic vagotomized C57BL/6J mice, KC-eliminated C57BL/6J mice, and α7nAChR mice were used for HIR. Primary KCs and hepatocytes were subjected to hypoxia/reoxygenation (HR). Liver injury, hepatocyte apoptosis, reactive oxygen species (ROS) production, and soluble CD163 were measured. RESULTS: Hepatic vagotomy and α7nAChR caused higher levels of alanine transaminase and liver caspase-3 and -8 activity by HIR. Activating α7nAChR attenuated these changes in wild-type but not in the α7nAChR mice. Furthermore, activating α7nAChR diminished hepatic injury and reduced liver apoptosis by HIR in vagotomized mice. In vitro, activating α7nAChR reduced apoptosis of hepatocytes cocultured with KCs that suffered HR. Similar to the effects by catalase, activating α7nAChR on KCs reduced ROS and H2O2 by HR. The supernatant from KCs, with α7nAChR activated or catalase treated, prevented hepatocyte apoptosis by HR. Finally, KC elimination reduced HIR-induced H2O2 production in mice. Activating α7nAChR significantly attenuated soluble CD163 both in mice by HIR (serum: 240 ± 34 vs. 446 ± 72; mean ± SD; n = 8; P < 0.01) and in KCs by HR (supernatant: 4.23 ± 0.06 vs. 5.60 ± 0.18; n = 3; P < 0.01). CONCLUSIONS: The vagus nerve could minimize HIR-induced liver apoptosis through activating α7nAChR on KCs possibly by preventing their excessive ROS production.

Capecitabine plus oxaliplatin (XELOX) compared with 5-fluorouracil/leucovorin plus oxaliplatin (FOLFOXs) in advanced gastric cancer: meta-analysis of randomized controlled trials.

PURPOSE: The study aims to compare the efficacy and safety of capecitabine plus oxaliplatin (XELOX) with 5-fluorouracil/leucovorin plus oxaliplatin (FOLFOXs) in patients with advanced gastric cancer. METHODS: Five databases were searched up to June 2014, without language restrictions. The outcomes included overall response rate (ORR), clinical benefit rate (CBR), and toxicity. RESULTS: Twenty-six eligible trials were selected from 178 studies that initially were identified. All trials were published in Chinese journals between 2005 and 2014 and included 1585 patients (787 in XELOX group and 798 in FOLFOXs group). The pooled results failed to show statistical significance of XELOX regimen on ORR (OR 1.18, 95% CIs 1.00-1.41, P = 0.057) and CBR (OR 1.10, 95% CIs 0.95-1.28, P = 0.191) as compared with FOLFOXs regimen. None of the 26 clinical trials reported progression-free survival, and only one reported overall survival rate. The meta-analysis demonstrated that XELOX regimen was associated with a significant lower risk with nausea, stomatitis, diarrhea and alopecia, and a significant higher risk of hand-foot syndrome. CONCLUSIONS: The evidence is limited to suggest that XELOX may share similar efficacy as FOLFOXs and reduce toxicities of chemotherapy in advanced gastric cancer therapy. However, owing to limited data and potential bias of the included studies, further rigorously controlled trials are required.

Activation of α7 nicotinic acetylcholine receptor protects against oxidant stress damage through reducing vascular peroxidase-1 in a JNK signaling-dependent manner in endothelial cells.

AIM: Alpha7 nicotinic acetylcholine receptor (α7nAChR), a subtype of nAChR regulating neurotransmission in central nervous system, is an essential regulator of cholinergic anti-inflammatory pathway in periphery. The present study was to determine the effects of activation of α7nAChR on oxidant stress-induced injury in endothelial cells. METHODS: Cultured human umbilical vein endothelial cells were treated with H2O2 (400 µM) or H2O2 plus PNU-282987 (10 µM). Cell viability and membrane integrity were measured. Annexin V + PI assay, immunoblotting of bcl-2, bax and cleaved capase-3, and immunofluorescence of apoptosis inducing factor (AIF) were performed to evaluate apoptosis. Protein expression of vascular peroxidase-1 (VPO-1) and phosphor-JNK were measured by immunoblotting. RESULTS: Activation of α7nAChR by a selective agonist PNU-282987 prevented H2O2-indced decrease of cell viability and increase of lactate dehydrogenase release. Activation of α7nAChR markedly reduced cell apoptosis and intracellular oxidative stress level. Moreover, activation of α7nAChR reduced H2O2-induced VPO-1 protein upregulation and JNK1/2 phosphorylation. The inhibitory effect of α7nAChR activation on VPO-1 was blocked by JNK inhibitor SP600125. In addition, pretreatment of α7nAChR antagonist methyllycaconitine blocked the cytoprotective effect of PNU-282987. CONCLUSION: These results provide the first evidence that activation of α7nAChR protects against oxidant stress-induced damage by suppressing VPO-1 in a JNK signaling pathway-dependent manner in endothelial cells.

Glibenclamide attenuates myocardial injury by lipopolysaccharides in streptozotocin-induced diabetic mice.

BACKGROUND: Sepsis is a common disease that continues to increase in incidence in the world. Diseases, such as diabetes mellitus, may make the situation worse. Diabetic patients are at increased risk for common infections. This study was designed to investigate the role of glibenclamide on myocardial injury by lipopolysaccharides (LPS) in streptozotocin induced diabetic mice (STZ-mice). METHODS: LPS was used to induce endotoxemia in STZ-mice. Heart rate and mean arterial pressure were measured by MPA-HBBS. Serum epinephrine level was measured by enzyme-linked immunosorbent assays (ELISA). Myocardial injury was examined by light and transmission electron microscope and TUNEL staining. Macrophage infiltration was measured by immunohistochemistry. Interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) levels in myocardial tissue and serum in STZ-mice, and in conditional medium of primary cultured peritoneal macrophages were determined by ELISA. Nalp3 and Caspase-1 protein levels were measured by Western blotting analysis. RESULTS: STZ administration decreased body weight and increased blood glucose in C57BL/6 mice. LPS injection caused decreases of heart rate and mean arterial pressure, and elevated serum epinephrine level in C57BL/6 mice. Compared with control mice without STZ treatment, LPS induced more severe myocardial injury and macrophage infiltration in STZ-mice, which was attenuated by pretreatment of glibenclamide. LPS stimulation enhanced the levels of IL-1ß and TNF-α in both cardiac tissue and serum. Glibenclamide pretreatment significantly inhibited the serum levels of pro-inflammatory cytokines. Either high glucose or LPS increased the levels of IL-1ß and TNF-α in the conditional medium of peritoneal macrophages. Glibenclamide treatment suppressed the increase of IL-1ß level induced by high glucose and LPS. Furthermore, Nalp3 and Caspase-1 levels were markedly increased by high glucose plus LPS, and both proteins were significantly inhibited by glibenclamide treatment. CONCLUSIONS: We conclude that glibenclamide could attenuate myocardial injury induced by LPS challenge in STZ-mice, which was possibly related to inhibiting inflammation through Nalp3 inflammasomes.

High-salt diet enhances hippocampal oxidative stress and cognitive impairment in mice.

Previous evidence suggests that a high-salt (HS) diet may increase oxidative stress and contribute to the development of hypertension that is already present. Oxidative stress is thought to play a critical role in the development of neurodegenerative diseases. Lower dietary sodium intake putatively contributes to a lower rate of cognitive impairment; however, the specific effects of HS diet on cognitive function remain poorly understood. In this work, C57BL/6J mice were administered a normal-salt (NS) diet (0.4% NaCl) or a HS diet (7.0% NaCl) for 12 weeks, and cognitive ability and oxidative stress in the brain were measured. It was found that the HS diet significantly impaired retention of spatial memory. Additionally, superoxide anion production in the hippocampus was significantly increased in the HS diet mice compared with that in the NS mice. Interestingly, the antioxidant defense capacities for HS diet mice were markedly reduced in the hippocampus, but not in the cerebral cortex, compared with the NS mice. Taken together, these data demonstrate that HS diet directly impairs retention of spatial memory, which may be related to the increased oxidative stress observed in the hippocampus.

Stem cell therapy for bone repair: a systematic review and meta-analysis of preclinical studies with large animal models.

AIM: Injury to bone is a significant clinical challenge, due to its limited regenerative capacity. The current methods of repairing bone defect are surgical, highly invasive and not always successful. A systematic review and meta-analysis of preclinical studies involving large animals with bone defects were conducted to determine the treatment outcomes with stem cell therapies. METHODS: A random effects meta-analysis of the available studies was conducted to assess the treatment outcomes including the rate of new bone formation and new bone mineral density (BMD). Stratified analyses were also conducted by separating studies based on each characteristic independently. RESULTS: Pooled analysis of 20 preclinical studies showed a significant beneficial effect of stem cell therapy in increasing new bone formation (17.79%, 95% confidence interval [CI], 10.54, 25.03; P < 0.001) and BMD (276.94 mg cm(-2) , 95% CI, 62.71, 491.17; P < 0.001) for disease amelioration. Regarding new bone formation, a statistical improvement was similarly detected from randomized controlled trial groups (17.06%, 95% CI, 8.87, 25.24; P < 0.001) and cohort groups (17.43%, 95% CI, 10.79, 24.07; P < 0.001). Exploratory stratified analysis yielded significant predictors of new bone formation including cell number (<10(7) vs. ≥10(7) ; P = 0.048) and the route of cell delivery (combining with matrix scaffold showed more effect than direct cell injection, P = 0.041). The effect of stem cell therapy diminished after 12 weeks. CONCLUSION: The study results suggest that stem cell therapy improves new bone formation and BMD in bone defect models. Future trials should focus on the transplantation of ≥10(7) stem cells, especially using slow release biodegradable scaffolds or repetitive cell injections.

The role of HSP40 in cancer: Recent advances.

Heat shock proteins (HSPs) are a family of proteins involved in protein folding and maturation that are expressed by cells in response to stressors including heat shock. Recent studies have demonstrated that HSPs play major roles in carcinogenesis by regulating angiogenesis, cell proliferation, migration, invasion, metastasis, apoptosis, as well as therapy resistance to certain anticancer drugs. Despite being the largest and most diverse subgroup of the HSP family, HSP40 (DNAJ) is an understudied family of co-chaperones. HSP40 family members are also known to be involved in various types of cancers. In this article, we review the involvement of human HSP40 family members in various aspects of cancer biology. In addition, we highlight the possible potential of HSP40 as a tumor biomarker or drug target for improving the prognosis and treatment of cancer patients in the future.