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Background Metallothionein 1M (MT1M) functions to regulate cell proliferation and cancer metastasis. This study assessed the effects of MT1M overexpression and mouse double minute 2 homolog (MDM2) knockdown on the regulation of non-small cell lung cancer A549 cell viability, migration, and protein expression in vitro and explored the underlying molecular events. Methods A549 cells were stably infected with lentivirus carrying MT1M cDNA or transiently transfected MDM2 siRNA and/or treated with the p53 inhibitor for the assessment of changes in cell viability, wound healing, Transwell migration, and qRT-PCR and Western blot assays. Luciferase reporter assay was performed to investigate p53 binding to the MT1M promoter. Results The data showed that MT1M overexpression inhibited A549 cell viability and migration capacity in vitro, whereas the p53 inhibitor reversed the inhibition of A549 cell viability and migration caused by MT1M overexpression as well as the expression of MMP2, MMP9, and MMP14. Furthermore, knockdown of MDM2, an upstream inhibitor of p53 activity, was able to reduce A549 cell viability, migration, and protein expression. Thus, MDM2 knockdown had synergistic effects with MT1M overexpression on the suppression of A549 cell viability, migration, and protein expression. Conclusions In conclusion, MDM2 can bind to and phosphorylate p53 protein to inactivate the protein, thereby reducing MT1M expression and leading to tumor cell proliferation and migration.

Vascular dementia (VaD) is a complex disorder caused by reduced blood flow in the brain. However, there is no effective pharmacological treatment option available until now. Here, we reported that low-dose levamlodipine besylate could reverse the cognitive impairment in VaD mice model of right unilateral common carotid arteries occlusion (rUCCAO). Oral administration of levamlodipine besylate (0.1 mg/kg) could reduce the latency to find the hidden platform in the MWM test as compared to the vehicle group. Furthermore, vehicle-treated mice revealed reduced phospho-CaMKII (Thr286) levels in the hippocampus, which can be partially restored by levamlodipine besylate (0.1 mg/kg and 0.5 mg/kg) treatment. No significant outcome on microglia and astrocytes were observed following levamlodipine besylate treatment. This data reveal novel findings of the therapeutic potential of low-dose levamlodipine besylate that could considerably enhance the cognitive function in VaD mice.

Wound healing impairment is increasingly recognized to be a consequence of hyperglycemia-induced dysfunction of endothelial precursor cells (EPCs) in type 2 diabetes mellitus (T2DM). Metformin exhibits potential for the improvement of endothelial function and the wound healing process. However, the underlying mechanisms for the observed beneficial effects of metformin application remain to be completely understood. The present study assessed whether metformin, a widely used therapeutic drug for T2DM, may accelerate wound closure in T2DM db/db mice. Genetically hyperglycemic db/db mice were used as the T2DM model. Metformin (250 mg/kg/day; intragastric) was administered for two weeks prior to EPC collection and wound model creation in db/db mice. Wound healing was evaluated by alterations in the wound area and the number of platelet endothelial cell adhesion molecule-positive cells. The function of the isolated bone marrow-derived EPCs (BM-EPCs) was assessed by a tube formation assay. The number of circulating EPCs, and the levels of intracellular nitric oxide (NO) and superoxide (O2−) were detected by flow cytometry. Thrombospondin-1 (TSP-1) expression was determined by western blot analysis. It was observed that treatment with metformin accelerated wound healing, improved angiogenesis and increased the circulating EPC number in db/db mice. In vitro, treatment with metformin reversed the impaired BM-EPC function reflected by tube formation, and significantly increased NO production while decreasing O2− levels in BM-EPCs from db/db mice. In addition, TSP-1 expression was markedly attenuated by treatment with metformin in cultured BM-EPCs. Metformin contributed to wound healing and improved angiogenesis in T2DM mice, which was, in part, associated with stimulation of NO, and inhibition of O2− and TSP-1 in EPCs from db/db mice.

Refractory wound is a dreaded complication of diabetes and is highly correlated with EPC dysfunction caused by hyperglycemia. Acarbose is a widely used oral glucose-lowering drug exclusively for T2DM. Previous studies have suggested the beneficial effect of acarbose on improving endothelial dysfunction in patients with T2DM. However, no data have been reported on the beneficial efficacy of acarbose in wound healing impairment caused by diabetes. We herein investigated whether acarbose could improve wound healing in T2DMdb/dbmice and the possible mechanisms involved. Acarbose hastened wound healing and enhanced angiogenesis, accompanied by increased circulating EPC number indb/dbmice. In vitro, a reversed BM-EPC dysfunction was observed after the administration of acarbose indb/dbmice, as reflected by tube formation assay. In addition, a significantly increased NO production was also witnessed in BM-EPCs from acarbose treateddb/dbmice, with decreased O2levels. Akt inhibitor could abolish the beneficial effect of acarbose on high glucose induced EPC dysfunction in vitro, accompanied by reduced eNOS activation. Acarbose displayed potential effect in promoting wound healing and improving angiogenesis in T2DM mice, which was possibly related to the Akt/eNOS signaling pathway.

The aim of this study was to investigate the protective effect of simvastatin against radiation-induced tissue injury in mice. Mice were radiated with 4 Gy or 8 Gy after 20 mg/kg/d simvastatin treatment over 2 weeks. Morphological changes were observed in the jejunum and bone marrow, and apoptotic cells were determined in both tissues. Peripheral blood cells were counted, and the superoxide dismutase (SOD) activity and the malondialdehyde (MDA) level in tissues of both thymus and spleen were measured. Compared with the radiation-only group, 20 mg/kg/d simvastatin administration significantly increased the mean villi height and decreased apoptotic cells in jejunum tissue, and stimulated regeneration and reduced apoptotic cells in bone marrow. Peripheral blood cell analysis revealed that simvastatin treatment induced a larger number of red blood cells and increased the hemoglobin level present after 4 Gy of radiation. Interestingly, it was also found that the number of peripheral endothelial progenitor cells was markedly increased following simvastatin administration. Antioxidant determination for tissues displayed that simvastatin therapy increased the SOD activity after both 4 and 8 Gy of radiation, but only decreased the MDA level after 4 Gy. Simvastatin ameliorated radiation-induced tissue damage in mice. The radioprotective effect of simvastatin was possibly related to inhibition of apoptosis and improvement of oxygen-carrying and antioxidant activities.

Background Endothelial dysfunction has been suggested as a possible causal link between hyperglycemia and microvascular complications in diabetes mellitus. The effect of metformin on endothelial progenitor cells (EPCs) is still unclear. This study was designed to test the hypothesis that metformin could accelerate wound healing by improving the impaired EPC functions in streptozotocin-induced diabetic mice. Methods Streptozotocin (STZ, 60 mg/kg/d × 5 d, i.p.) was injected to induce type 1 diabetes in male C57BL/6 mice. Mice were treated with metformin (250 mg/kg/d, i.g.) for consecutive 14 days. Wound closure was evaluated by wound area and number of CD31 stained capillaries. Functions of bone marrow-endothelial progenitor cells (BM-EPCs) were assessed by tube formation and migration assays, and expression of AMP-activated protein kinase (AMPK) and endothelial nitric oxide synthase (eNOS) was determined by western blot analysis. Results Metformin accelerated wound closure and stimulated angiogenesis in diabetic mice. The number of circulating EPCs was increased significantly in metformin treated diabetic mice. Abilities of tube formation and migration of BM-EPCs were impaired in diabetic mice, which were improved by metformin. Expression of both phosphorylated-AMPK and phosphorylated-eNOS was significantly increased, and nitric oxide (NO) production was enhanced by metformin in BM-EPCs of diabetic mice. In vitro, metformin improved impaired BM-EPC functions, and increased phosphorylated-eNOS expression and NO production in cultured BM-EPCs caused by high glucose, which was prevented by the AMPK inhibitor compound C. Conclusions Our results suggest that metformin could improve BM-EPC functions in STZ-induced diabetic mice, which was possibly dependent on the AMPK/eNOS pathway. Electronic supplementary material The online version of this article (doi:10.1186/s12933-016-0408-3) contains supplementary material, which is available to authorized users.

Endothelial cell dysfunction is the primary cause of microvascular complications in diabetes. Diazoxide enables beta cells to rest by reversibly suppressing glucose-induced insulin secretion by opening ATP-sensitive K+ channels in the beta cells. This study investigated the role of diazoxide in wound healing in mice with streptozotocin (STZ)-induced diabetes and explored the possible mechanisms of its effect. Compared to the controls, mice with STZ-induced diabetes exhibited significantly impaired wound healing. Diazoxide treatment (30 mg/kg/d, intragastrically) for 28 days accelerated wound closure and stimulated angiogenesis in the diabetic mice. Circulating endothelial progenitor cells (EPCs) increased significantly in the diazoxide-treated diabetic mice. The adhesion, migration, and tube formation abilities of bone marrow (BM)-EPCs were impaired by diabetes, and these impairments were improved by diazoxide treatment. The expression of both p53 and TSP-1 increased in diabetic mice compared to that in the controls, and these increases were inhibited significantly by diazoxide treatment. In vitro, diazoxide treatment improved the impaired BM-EPC function and diminished the increased expression of p53 and TSP-1 in cultured BM-EPCs caused by high glucose levels. We conclude that diazoxide improved BM-EPC function in mice with STZ-induced diabetes, possibly via a p53- and TSP-1-dependent pathway.

Clinical trials with partial liquid ventilation demonstrate improvement in oxygenation, as well as some adverse side effects linked to the application of liquid perfluorocarbons (PFCs) during liquid ventilation. Thus, we examined the effects of systemic administration of PFC on acute lung injury (ALI) induced by lipopolysaccharide (LPS) and its effects on heme oxygenase-1 (HO-1), a compound that provides potent cytoprotection against lung injury. Rats were assigned to one of six groups (n = 8). Thirty minutes after they were challenged with LPS aerosol inhalation, perfluorohexane was given intraperitoneally every two hours. Ten hours after LPS inhalation, bronchoalveolar lavage fluid (BALF) and lung tissue were obtained for enzyme linked immunosorbent assay, histologic, and Western-blot analyses. The results showed that perfluorohexane significantly decreased the wet to dry weight ratio, malondialdehyde (MDA) production, and myeloperoxidase (MPO) activity in the lung tissue. Also, perfluorohexane reduced the total protein content and levels of tumor necrosis factor-alpha (TNF-alpha) but increased the levels of the anti-inflammatory cytokine interleukin-10 (IL-10) in the BALF, resulting in decreased pulmonary edema and the infiltration of neutrophils into the lung tissues of LPS-treated rats. Furthermore, perfluorohexane increased HO-1 protein production and stimulated HO-1 activity in the lung tissue. Pre-treatment with Zinc protoporphyrin IX, an inhibitor of HO-1, decreased the protective effects of perfluorohexane in rats. In summary, systemic perfluorohexane alleviates LPS-induced lung injury in rats, and HO-1 may be involved in the mechanism of this reduction.

Cardio-cerebral-vascular diseases, including myocardial infarction, atherosclerosis, hypertension, and stroke etc, are the major reasons for morbidity and mortality all over the world. Recent studies showed that inflammation exerts an important impact on the pathogenesis and development of cardio-cerebral-vascular diseases. "The cholinergic anti-inflammatory pathway", mainly modulated through α7 nicotinic acetylcholine receptor (α7nAChR), has attracted much attention.The purpose of this review was to discuss the role of α7nAChR during the pathological processes in myocardial infarction, atherosclerosis, hypertension and stroke.Most of the existing literatures involved in studying on myocardial infarction, atherosclerosis, hypertension and stroke showed that activation of α7nAChR might be a potential strategy for the prevention and treatment of these diseases.Targeting α7nAChR to combat inflammation might be a novel therapy in cardiocerebral- vascular diseases.

Background & AimsMetformin is currently the most widely used first-line hypoglycemic agent for diabetes mellitus. Besides glucose-lowering action, there is increasingly interest in the potential anti-inflammatory action of this drug. In the present study, we investigated the actions of metformin on experimental insulitis using STZ-induced diabetic mice.MethodsMice with acute diabetes induced by STZ were administered metformin by gavage. Changes of blood glucose and body weight, and the daily amount of food and water intake were measured. Pancreatic tissues were collected for histologic analyses. Pathological assessment and immunohistochemistry analysis were used to determine the effect of metformin on insulitis. Inflammatory cytokines in the pancreas and insulin levels were measured through ELISA analysis.ResultsMetformin significantly reduced blood glucose levels and improved aberrant water intake behavior in experimental diabetic mice. No significant differences were observed in terms of body weight and food intake behavior in metformin-treated animals. In the STZ-induced model of diabetes, we found the appearance of pronounced insulitis. However, metformin administration reduced the severity of insulitis assessed by blind pathological scoring. In addition, metformin treatment improved insulin levels in experimental diabetic mice. ELISA assay revealed decreased levels of inflammatory response marker IL-1βand TNF-αin the pancreatic tissues following metformin treatment.ConclusionMetformin attenuated insulitis in the STZ-induced mice model of diabetes. This islet-protective effect might be partly correlated with the anti-inflammatory action of metformin.

Background and Purpose— In our current food supply, sugar substitutes are widely used in beverages and other food products. However, there is limited information about the link between dietary consumption of sugar substitutes and stroke to date. This study sought to determine the effect of various sugar substitutes on the cerebral ischemic injury and endothelial progenitor cells, which have been implicated to play an important role in vascular repair and revascularization in ischemic brain tissues, in mice. Methods— After treatment with sucrose and various sugar substitutes (the doses are in the range of corresponding acceptable daily intake levels) and vehicle for 6 weeks, mice were subjected to permanent left middle cerebral artery occlusion, and the infarct volumes, angiogenesis, and neurobehavioral outcomes were determined. In addition, the number and function of endothelial progenitor cells were also examined. Results— After long-term treatment with fructose, erythritol (sugar alcohols), acesulfame K (artificial sweeteners), or rebaudioside A (rare sugars), the cerebral ischemic injury (both infarct volumes and neurobehavioral outcomes) was significantly aggravated, angiogenesis in ischemic brain was reduced, and endothelial progenitor cell function was impaired in mice compared with control. However, the similar impairments were not found in sucrose (with the same dose as fructose’s)-treated mice. Conclusions— Long-term consumption of sugar substitutes aggravated cerebral ischemic injury in mice, which might be partly attributed to the impairment of endothelial progenitor cells and the reduction of angiogenesis in ischemic brain. This result implies that dietary intake of sugar substitutes warrants further attention in daily life.

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-1β (IL-1β) 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-1β 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-1β and TNF-α in the conditional medium of peritoneal macrophages. Glibenclamide treatment suppressed the increase of IL-1β 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. Electronic supplementary material The online version of this article (doi:10.1186/s12933-014-0106-y) contains supplementary material, which is available to authorized users.

Previous studies on the antioxidant activity of sedatives have predominantly been in vitro investigations that are lacking clinical data, resulting in conclusion without cogency. The aim of the present prospective, randomized study was to use single sedative drugs for anesthesia induction to compare their antioxidant properties. The effects on the antioxidant system of midazolam, propofol and dexmedetomidine were assessed using oxidative stress indicators and micronuclei (MN). Forty-nine patients undergoing esophageal cancer radical prostatectomy were selected. Midazolam, propofol and dexmedetomidine were used to induce anesthesia. Venous blood samples were obtained prior to and at 2 and at 24 h after surgery, and oxidative stress indicators were detected using the appropriate kits. The cytokinesis-block micronucleus cytome assay was executed and the frequencies of MN, nucleoplasmic bridges and nuclear buds were examined. It was found that the use of the three sedatives, respectively, led to a marked increase in the levels of free radical indicators at 2 h after surgery, which then decreased at 24 h after surgery. Furthermore, lower levels of oxidative stress were found following the use of propofol and dexmedetomidine compared with those following midazolam administration, and similar results were obtained regarding the level of MN. It is suggested that propofol and dexmedetomidine exhibit a superior antioxidant function to midazolam.

The aim of the present study was to investigate whether the JWA gene regulates the proliferation, migration and invasion of human esophageal squamous cell carcinoma (ESCC) and normal human esophageal cell lines through mitogen-activated protein kinase (MAPK) signal transduction pathways. The role of JWA in proliferation, migration, invasion and apoptosis was investigated in the Eca109 human ESCC and HET-1A normal human esophageal cell lines via transfection with JWA-small interfering (si)RNA. Western blot analysis was conducted to observe the effect of JWA on apoptosis and the regulatory effect of JWA on proliferation was determined using a thiazolyl blue tetrazolium bromide (MTT) assay. Cellular migration and invasion were analyzed via a Transwell assay. In addition, the expression levels of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38 MAPK following JWA-siRNA transfection were detected by western blot analysis and compared with those of untreated cells. The downregulation of JWA protein decreased apoptosis and increased the proliferation, migration and invasion of the Eca109 and HET-1A cell lines. In the Eca109 cell line, the expression levels of phosphorylated (p)-ERK1/2 and p-JNK, but not those of p-p38, decreased significantly in the JWA siRNA group compared with those in the control groups. However, in the HET-1A cell line, JWA-siRNA transfection significantly inhibited the expression of p-p38 and demonstrated no effect on the expression levels of p-ERK1/2 and p-JNK. In conclusion, the JWA gene may regulate the ESCC and human esophageal cell lines through MAPK signaling pathways via different regulatory mechanisms.

Radiation-induced gastrointestinal syndrome occurs when the body is exposed to a high dose of radiation. Currently, safe and effective radioprotectants are not available. Apoptosis was reported to play a primary role in radiation-induced injury. Recent evidence suggests that stimulation of α7 nicotinic acetylcholine receptor (α7nAChR) prevents cell death by inhibition of apoptosis. In this study, we demonstrated that a single dose of PNU282987 (100 μg/kg, i.p.), a selective α7nAChR agonist, protected mice from intestinal injury and significantly improved survival when administered prior to lethal 8 Gy total body irradiation. In vitro, PNU282987 protected against 8 Gy radiation-induced cell death in human umbilical venous endothelial cells by inhibiting apoptosis. We conclude that activation of α7nAChR may provide a new therapeutic pathway for the treatment of radiation-induced damage and mortality.

Background Cardiac dysfunction is well-described in endotoxemia and diagnosed in up to 60% of patients with endotoxic shock. ATP-sensitive potassium (KATP) channels are critical to cardiac function. This study investigates the role of Kir6.2 subunits of KATP channels on cardiac dysfunction in lipopolysaccharide (LPS)-induced endotoxemia. Methods Kir6.2 subunits knockout (Kir6.2−/−) and wild-type (WT) mice were injected with LPS to induce endotoxemia. Cardiac function was monitored by echocardiography. Left ventricles were taken for microscopy (both light and electron) and TUNEL examination. Serum lactate dehydrogenase (LDH) and creatine kinase (CK) activities, and tumor necrosis factor-α (TNF-α) levels in both serum and left ventricular tissues were determined. Results Compared to WT, Kir6.2−/− mice showed significantly declined cardiac function 360 min after LPS administration, aggravated myocardial damage and elevated serum LDH and CK activities. Apoptotic cells were obviously increased in heart tissues from Kir6.2−/− mice at 90, 180 and 360 min. TNF-α expression in both serum and heart tissues of Kir6.2−/− mice was significantly increased. Conclusions We conclude that Kir6.2 subunits are critical in resistance to endotoxemia-induced cardiac dysfunction through reducing myocardial damage by inhibition of apoptosis and inflammation. KATP channels blockers are extensively used in the treatment of diabetes, their potential role should therefore be considered in the clinic when patients treated with antidiabetic sulfonylureas are complicated by endotoxemia.