ABSTRACT
Purpose@#Gastric cancer (GC) has high morbidity and mortality and is a serious threat to public health. The flavonoid compound vitexin is known to exhibit anti-tumor activity. In this study, we explored the therapeutic potential of vitexin in GC and its underlying mechanism. @*Materials and Methods@#The viability, migration, and invasion of GC cells were determined using MTT, scratch wound healing, and transwell assays, respectively. Target molecule expression was determined by western blotting. Tumor growth and liver metastasis were evaluated in vivo using nude mice. Protein expression in the tumor tissues was examined by immunohistochemistry. @*Results@#Vitexin inhibited GC cell viability, migration, invasion, and epithelial-mesenchymal transition (EMT) in a dose-dependent manner. Vitexin treatment led to the inactivation of phosphatidylinositol-3-kinase (PI3K)/AKT/hypoxia-inducible factor-1α (HIF-1α) pathway by repressing HMGB1 expression. Vitexin-mediated inhibition in proliferation, migration, invasion and EMT of GC cells were counteracted by hyper-activation of PI3K/AKT/HIF-1α pathway or HMGB1 overexpression. Finally, vitexin inhibited the xenograft tumor growth and liver metastasis in vivo by suppressing HMGB1 expression. @*Conclusions@#Vitexin inhibited the malignant progression of GC in vitro and in vivo by suppressing HMGB1-mediated activation of PI3K/Akt/HIF-1α signaling pathway. Thus, vitexin may serve as a promising therapeutic agent for the treatment of GC.
ABSTRACT
This study aimed to establish an animal model of decompression-induced lung injury (DILI) secondary to repetitive diving in mice and explore the role of macrophages in DILI and the protective effects of high-concentration hydrogen (HCH) on DILI. Mice were divided into three groups: control group, DILI group, and HCH group. Mice were exposed to hyperbaric air at 600 kPa for 60 min once daily for consecutive 3 d and then experienced decompression. In HCH group, mice were administered with HCH (66.7% hydrogen and 33.3% oxygen) for 60 min after each hyperbaric exposure. Pulmonary function tests were done 6 h after decompression; the blood was harvested for cell counting; the lung tissues were harvested for the detection of inflammatory cytokines, hematoxylin and eosin (HE) staining, and immunohistochemistry; western blotting and polymerase chain reaction (PCR) were done for the detection of markers for M1 and M2 macrophages. Our results showed that bubbles formed after decompression and repeated hyperbaric exposures significantly reduced the total lung volume and functional residual volume. Moreover, repetitive diving dramatically increased proinflammatory factors and increased the markers of both M1 and M2 macrophages. HCH inhalation improved lung function to a certain extent, and significantly reduced the pro-inflammatory factors. These effects were related to the reduction of M1 macrophages as well as the increase in M2 macrophages. This study indicates that repetitive diving damages lung function and activates lung macrophages, resulting in lung inflammation. HCH inhalation after each diving may be a promising strategy for the prevention of DILI.
Subject(s)
Animals , Male , Mice , Cell Polarity , Diving/adverse effects , Lung/physiology , Lung Injury/etiology , Macrophages/physiology , Mice, Inbred BALB C , Pulmonary Edema/etiologyABSTRACT
Methane is the simplest hydrocarbon, consisting of one carbon atom and four hydrogen atoms. It is abundant in marsh gas, livestock rumination, and combustible ice. Little is known about the use of methane in human disease treatment. Current research indicates that methane is useful for treating several diseases including ischemia and reperfusion injury, and inflammatory diseases. The mechanisms underlying the protective effects of methane appear primarily to involve anti-oxidation, anti-inflammation, and anti-apoptosis. In this review, we describe the beneficial effects of methane on different diseases, summarize possible mechanisms by which methane may act in these conditions, and discuss the purpose of methane production in hypoxic conditions. Then we propose several promising directions for the future research.
Subject(s)
Humans , Antioxidants/pharmacology , Apoptosis/drug effects , Inflammation/drug therapy , Ischemia/drug therapy , Methane/therapeutic use , Reperfusion Injury/drug therapyABSTRACT
BACKGROUND@#Asthma is a common cause of breathing difficulty in children and adults, and is characterized by chronic airway inflammation that is poorly controlled by available treatments. This results in severe disability and applies a huge burden to the public health system. Methane has been demonstrated to function as a therapeutic agent in many diseases. The aim of the present study was to explore the effect of methane-rich saline (MRS) on the pathophysiology of a mouse model of asthma and its underlying mechanism.@*METHODS@#A murine model of ovalbumin (OVA)-induced allergic asthma was applied in this study. Mice were divided into three groups: a control group, an OVA group, and OVA-induced asthmatic mice treated with MRS as the third group. Lung resistance index (RI) and dynamic compliance (Cdyn) were measured to determine airway hyper-responsiveness (AHR). Haematoxylin and eosin (H&E) staining was performed and scored to show histopathological changes. Cell counts of bronchoalveolar lavage fluid (BALF) were recorded. Cytokines interleukin (IL)-4, IL-5, IL-13, tumor necrosis factor α (TNF-α), and C-X-C motif chemokine ligand 15 (CXCL15) from BALF and serum were measured by enzyme-linked immunosorbent assay (ELISA). The oxidative stress indexes, including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), myeloperoxidase (MPO), and 8-hydroxydeoxyguanosine (8-OHdG), were determined using commercial kits. Apoptosis was evaluated by western blot, quantitative real-time polymerase chain reaction (qRT-PCR), and biochemical examination.@*RESULTS@#MRS administration reversed the OVA-induced AHR, attenuated the pathological inflammatory infiltration, and decreased the cytokines IL-4, IL-5, IL-13, TNF-α, and CXCL15 in serum and BALF. Moreover, following MRS administration, the oxidative stress was alleviated as indicated by decreased MDA, MPO, and 8-OHdG, and elevated SOD and GSH. In addition, MRS exhibited an anti-apoptotic effect in this model, protecting epithelial cells from damage.@*CONCLUSIONS@#Methane improves pulmonary function and decreases infiltrative inflammatory cells in the allergic asthmatic mouse model. This may be associated with its anti-inflammatory, antioxidative, and anti-apoptotic properties.
Subject(s)
Animals , Female , Mice , Apoptosis/drug effects , Asthma/metabolism , Bronchial Hyperreactivity/drug therapy , Cytokines/analysis , Inflammation/prevention & control , Methane/pharmacology , Mice, Inbred BALB C , Oxidative Stress/drug effects , Saline SolutionABSTRACT
Objective To investigate the effect of treatment with TNF-α on growth ability of colon cancer cells and its possible mechanism.Methods Human colon cancer HT-29 cells were treated with TNF-α(10 nmol/L). The effect of TNF-αon the proliferative ability was examined by cell growth curve assay and MTT assay,respectively. Cell cycle was detected by flow cytometry.Protein levels ofβ-catenin,c-myc and cyclinD1 were detected by Western blot.We also observed the effect of the Wnt/β-catenin pathway blockage by XAV9 3 9 on TNF-α's promoting prolif-eration of colon cancer cells and proteins related to the Wnt/β-catenin pathway.Results Upon treatment with TNF-α,the proliferative ability of HT-29 cells was enhanced (all P＜0.05),G0/G1 phase cell ratio was decreased (P＜0.05),and S phase cell ratio was increased (P＜0.05).The protein levels ofβ-catenin,c-myc and cyclinD1 were increased in TNF-α-treated HT-29 cells (all P＜0.05).XAV939 treatment resulted in a significant inhibition of cell proliferation ability (all P＜0.05)as well as the protein levels ofβ-catenin,c-myc and cyclinD1 (all P＜0.05) in the TNF-α-treated HT29 cells.Conclusion TNF-αmay be involved in the occurrence and development of colon cancer by activating the Wnt/β-catenin pathway and promoting the proliferation of colon cancer cells.
ABSTRACT
<p><b>BACKGROUND</b>Hyperbaric oxygen preconditioning (HBO) is a new method of ischemia preconditioning. In this study, we examined its effects on skin flap survival and the mechanisms involved.</p><p><b>METHODS</b>Thirty-six rats were divided into three groups: HBO preconditioning, control, and sham groups. An extended epigastric adipocutaneous flap based on the right superficial epigastric artery and vein was raised. A 3-hour period of flap ischemia was induced by clamping the pedicle vessels with a microvascular clamp. At the end of ischemia induction, the clamp was removed and the flap was resutured. Rats in the HBO preconditioning group were treated with HBO four times before surgery. Microcirculation in the skin flap was measured on postoperative days 1, 3 and 5. The size of the flap was measured on postoperative day 5, before the animals were sacrificed. Samples of the skin flap were prepared and stained with hematoxylin and eosin. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in the flap samples were measured.</p><p><b>RESULTS</b>Surviving flap size was significantly higher in the HBO preconditioning group compared with controls, with a reduced inflammatory response and increased perfusion. IL-1, TNF-α, and IL-6 levels in the HBO preconditioning group were lower than in controls.</p><p><b>CONCLUSIONS</b>HBO preconditioning improved flap survival in this ischemia-reperfusion rat model. The mechanisms responsible for this effect may relate to attenuation of the inflammatory response and increased flap perfusion following HBO preconditioning.</p>
Subject(s)
Animals , Male , Rats , Graft Survival , Hyperbaric Oxygenation , Methods , Ischemia , General Surgery , Microcirculation , Physiology , Rats, Sprague-Dawley , Skin , Surgical FlapsABSTRACT
Recently, Ohsawa et al. provide evidence that inhaled hydrogen gas has antioxidant and antiapoptotic activities that protect the brain and liver against ischemia-reperfusion injury. In fact,there is some endogenous hydrogen produced by intestinal bacteria within animal and human. The concentration of hydrogen in some mice tissues reached the antioxidant effect in their paper demonstrates, so we think that hydrogen should be an endogenous antioxidant in the body.
ABSTRACT
Recently,Ohsawa et al. provide evidence that inhaled hydrogen gas has antioxidant and antiapoptotic activities that protect the brain and liver against ischemia-reperfusion injury. In fact,there is some endogenous hydrogen produced by intestinal bacteria within animal and human.The concentration of hydrogen in some mice tissues reached the antioxidant effect in their paper demonstrates,so we think that hydrogen should be an endogenous antioxidant in the body.
ABSTRACT
Recently,Ohsawa et al. provide evidence that inhaled hydrogen gas has antioxidant and antiapoptotic activities that protect the brain and liver against ischemia-reperfusion injury. In fact,there is some endogenous hydrogen produced by intestinal bacteria within animal and human.The concentration of hydrogen in some mice tissues reached the antioxidant effect in their paper demonstrates,so we think that hydrogen should be an endogenous antioxidant in the body.
ABSTRACT
Oxygen is a mandatory for all aerobic organisms. Oxygen-containing free radicals are produced when oxygen is not completely reduced to water in energy-producing oxidation reaction. The radicals may also transform into other reactive compounds through electron transfer and all the compounds with similar functions are referred as reactive oxygen species (ROS). Increased ROS is known to cause damage to proteins, DNA and lipids. Much evidence showed that changes in partial oxygen pressure, hormone, cytokine and chemical stimulation could increase ROS, and ROS, acting as signaling molecules, mediates cell functions. Hypoxia-inducing factor (HIF), a key transcriptional factor for most hypoxia-inducible genes, is a heterodimer consisting of 2 subunits. Recent study found that ROS plays an important role in HIF activity regulation under hypoxic and non-hypoxic conditions. This paper reviews the production of ROS and its role in the regulation of HIF activity.
ABSTRACT
The purpose of the present study was to explore the relation between the modulation of cerebral blood flow and the latency of hyperbaric oxygen-induced convulsion. There were two parts in this study. First, the effect of acetazolamide or (and) indomethacin on the latency of hyperbaric oxygen-induced convulsion was observed. Seventy Sprague-Dawley (SD) rats were randomly divided into 7 groups: the acetazolamide 200, 20, 10, 7.5, 5, 2.5 mg/kg body weight and normal saline (NS) group. Forty rats were divided into 5 groups: indomethacin 20, 10, 5, 2.5 mg/kg body weight and NS groups. Another 40 rats were divided into 5 groups which were administered with indomethacin in the dose of 0 mg/kg (NS), 0 mg/kg (NS), 5, 10 and 20 mg/kg body weight. Thirty min later the first group was given NS, and all the other four groups were given acetazolamide with a dose of 7.5 mg/kg body weight. The animals were given acetazolamide or (and) indomethacin intraperitoneally, and 20 min later they were exposed to the pressure of 6 ATA (absolute atmosphere) of pure oxygen. The time from exposure to the onset of seizure (clonic-tonic convulsion) was recorded for each animal according to behavioral observation. Second, the change of maleic dialdehyde (MDA) was measured after acetazolamide and (or) indomethacin treatment. Seventy-two SD rats were randomly divided into 9 groups: Control, 6 and 16 min respectively with NS, acetazolamide, indomethacin, and both acetazolamide and indomethacin group. The dose of acetazolamide was 7.5 mg/kg body weight and the dose of indomethacin was 20 mg/kg body weight. After injection of drugs, the animals were subjected to the pressure of 6 ATA of pure oxygen in respect to its time course group. Then the rats were decapitated and the cerebral cortex was dissected and homogenized. The content of MDA was determined. We found that (1) when the dose of acetazolamide is higher than 7.5 mg/kg, it shortened the latency to hyperbaric oxygen-induced convulsion significantly (P<0.05, P<0.01). There was no significant difference in the latency between every to hyperbaric oxygen-induced convulsion significantly (P<0.05, P<0.01). There was no significant difference in the latency between every two groups of rats treated with different doses of indomethacin. But when the rats were administered acetazolamide of 7.5 mg/kg body weight after being pretreated with indomethacin of 20 mg/kg body weight, the outbreak of convulsion was put off remarkably (P<0.05). (2) In comparison with the control, the content of MDA in the group treated with acetazolamide increased significantly (P<0.01), but when the rats were treated with both acetazolamide and indomethacin, the content of MDA was reduced significantly both in 6 and 16 min exposure time projects (P<0.05, P<0.01). These results suggest that acetazolamide which dilates the brain arterioles can obviously shorten the latency of hyperbaric oxygen-induced convulsion and aggravate the oxidation of the brain. Indomethacin can resist acetazolamideos effect on the latency and oxidation level when the animals were exposed to the hyperbaric oxygen. The activity of carbonic anhydrase correlates closely with the oxidation injury.
ABSTRACT
The purpose of the present study was to explore the relation between the modulation of cerebral blood flow and the latency of hyperbaric oxygen-induced convulsion. There were two parts in this study. First, the effect of acetazolamide on the latency of hyperbaric oxygen-induced convulsion was observed. 32 Sprague-Dawley (SD) rats were randomly divided into four groups: the acetazolamide 200, 20, 2 mg/kg body weight and normal saline (NS) group. The animals were given intraperitoneally acetazolamide or NS, respectively, before being exposed to the pressure of 6 ATA (absolute atmosphere) of pure oxygen. The time from exposure to the onset of seizure (clonic-tonic convulsion) was recorded for each animal according to behavioral observation. Second, the changes in maleic dialdehyde (MDA) and the activity of glutathione peroxidase (GSH-PX) were measured after acetazolamide treatment. 40 SD rats were randomly divided into five groups: NS group, 6 min with NS group, 6 min with acetazolamide group, 16 min with NS group, and 16 min with acetazolamide group. The dose of acetazolamide was 20 mg/kg body weight. After injection of NS or acetazolamide, the animals were subjected to the pressure of 6 ATA of pure oxygen in respect to its time course group. The rats were decapitated and the cortex, hippocampus, and striatum of brains were dissected and homogenized. The content of MDA and the activity of GSH-PX in these tissues were determined. We found that (1) there was a significant difference in the latency of hyperbaric oxygen-induced convulsion between the acetazolamide 200 mg/kg group and the NS control group, as well as between the acetazolamide 20 mg/kg group and the NS control group (P<0.01), whereas there was no significant difference between the NS group and the acetazolamide 2 mg/kg weight group (P>0.05). The latency of these groups were listed as follows: 9.78+/-1.94 min for 200 mg/kg body weight group, 10.92+/-1.68 min for 20 mg/kg body weight group, 24.32+/-4.33 min for 2 mg/kg body weight group and 22.02+/-4.32 min for NS control group. (2) there was no significant difference between all groups in the activity of GSH-PX, though it varied with the oxidation levels. In the cortex and hippocampus, the activity of GSH-PX boosted up at first, but with the progress of the oxidation it was impaired. In the striatum, the activity of GSH-PX increased stepwise with the aggravation of the oxidation. The MDA content in the cortex increased significantly in the group of 6 min with acetazolamide (P<0.01), as well as the group of 16 min with acetazolamide group both in cortex and hippocampus (P<0.01, P<0.05). The MDA content of all groups is correlated with the dose of acetazolamide and the exposure time. These results suggest that acetazolamide which dilates the brain arteriolar obviously shortens the latency of hyperbaric oxygen-induced convulsion, and that acetazolamide dilates the vessels and increases the supply of the oxygen breaking into the brain tissues and aggravates the oxidation. The hyperbaric oxygen-induced convulsion correlates closely with the oxidation injury.
Subject(s)
Animals , Male , Rats , Acetazolamide , Pharmacology , Brain , Pathology , Hyperbaric Oxygenation , Oxidative Stress , Oxygen , Random Allocation , Rats, Sprague-Dawley , Seizures , Vasodilator Agents , PharmacologyABSTRACT
<p><b>AIM</b>To investigate the preventive effects of Panax notoginseng saponins (PNS) and Ginkgo biloba extracts (GbE) on acute oxygen toxicity and the possible mechanisms.</p><p><b>METHODS</b>Mice were injected intraperitoneally with PNS and GbE for 5 days, then were exposed to 500 kPa hyperbaric oxygen (HBO) for 60 min, the convulsion latency, times and interval were observed. Moreover, reactive oxygen (RO) unit, MDA, NO, GSH levels and GSH-Px, CAT, MAO activities of mice brain were determined after they were exposed to HBO for 15 min.</p><p><b>RESULTS</b>PNS and GbE could markedly prolong the convulsion latency and interval, reduce convulsion times, decrease contents of MDA and NO in mice brain, keep RO unit, GSH and GSH-Px at higher levels, but had no effects on CAT and MAO activities.</p><p><b>CONCLUSION</b>PNS and GbE could effectively prevent acute oxygen toxicity, which were related to their antioxidant activities.</p>