Characterization of Sepsis and Sepsis-Associated Encephalopathy.

BACKGROUND: Sepsis and sepsis-associated encephalopathy (SAE) are common intensive care unit (ICU) diseases; the morbidity and mortality are high. The present study analyzed the sensitivity of different diagnostic criteria of sepsis 1.0 and 3.0, epidemiological characteristics of sepsis and SAE, and explored its risk factors for death, short-term, and long-term prognosis. METHODS: The retrospective study included patients in ICU from January 2015 to June 2016. After excluding 58 patients, 175 were assigned to either an SAE or a non-SAE group (patients with sepsis but no encephalopathy). The sensitivity of the diagnostic criteria was compared between sepsis 1.0 and 3.0, respectively. Between-group differences in baseline data, Acute Physiology and Chronic Health Evaluation II score (APACHE II score), Sequential Organ Failure Assessment score (SOFA score), etiological data, biochemical indicators, and 28-day and 180-day mortality rates were analyzed. Survival outcomes and long-term prognosis were observed, and risk factors for death were analyzed through 180-day follow-up. RESULTS: The sensitivity did not differ significantly between the diagnostic criteria of sepsis 1.0 and 3.0 (P = .286). The 42.3% incidence of SAE presented a significantly high APACHE II and SOFA scores as well as 28-day mortality and 180-day mortality (all P < .001). The incidence of death was 37.1%. The multivariate stepwise regression analysis demonstrated that the risk of death in SAE group was significantly higher than the non-SAE group (P < .001). Sepsis-associated encephalopathy is a risk factor for sepsis-related death (relative risk [RR] = 2.868; 95% confidence interval: 1.730-4.754; P < .001). Although males showed a significantly high rate of 28-day and 180-day mortality (P = .035 and .045), it was not an independent risk factor for sepsis-related death (P = .072). The long-term prognosis of patients with sepsis was poor with decreased quality of life. No significant difference was observed in prognosis between the SAE and non-SAE groups (P > .05). CONCLUSION: Both diagnostic criteria cause misdiagnosis, and the sensitivity did not differ significantly. The incidence of SAE was high, and 28-day and 180-day mortality rates were significantly higher than those without SAE. Sepsis-associated encephalopathy is a risk factor for poor outcome. The overall long-term prognosis of patients with sepsis was poor, and the quality of life decreased.

miR-451 inhibits cell growth, migration and angiogenesis in human osteosarcoma via down-regulating IL 6R.

Osteosarcoma (OS) has become one of the most common primary malignant tumors in the children and adolescents with a poor prognosis owing to its high malignant and metastatic potential. Although increasing evidence indicates that miR-451 could inhibit the growth and metastasis of OS, its effect on angiogenesis in OS is still very poor. What is more, the mechanism by which miR-451 affects the OS has not been fully elucidated. In the present study, miR-451 was reduced in human osteosarcoma tissues compared with the adjacent bone tissues, and the introduction of miR-451 dramatically inhibited the growth, migration and angiogenesis in OS. Additionally, it was suggested that IL 6R is a direct target gene of miR-451. Silencing of IL 6R suppressed the growth, migration and angiogenesis of OS, which was consistent with the effect of overexpression of miR-451. In conclusion, our data demonstrate that miR-451 may function as a potential suppressor of tumor growth, migration and angiogenesis in OS via down-regulating IL 6R, suggesting a promising therapeutic avenue for managing OS.

Hemin protects against oxygen-glucose deprivation-induced apoptosis activation via neuroglobin in SH-SY5Y cells.

This study aimed to investigate the mechanism underlying the neuroprotective effect of hemin in oxygen-glucose deprivation (OGD)-treated neurons. OGD-treated SH-SY5Y cells (human neuroblastoma cells) were used in the study. The cellular viability of SH-SY5Y cells was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the cell apoptosis rate was determined by flow cytometry analysis with Annexin V-fluorescein isothiocyanate and propidium iodide staining with or without hemin pretreatment. Cell viability and apoptotic activation were detected after hemin administration combined with neuroglobin (Nqb), thioredoxin-1, peroxiredoxin-2, or heme oxygenase-1 siRNA transient transfection. The release of cytochrome c from mitochondria and the interaction between Ngb and cytochrome c were examined with hemin pretreatment. Hemin had a neuroprotective effect in OGD-treated SH-SY5Y cells, which was mainly mediated by the upregulation of Ngb. Moreover, the release of cytochrome c from mitochondria was inhibited by hemin-induced Ngb expression through facilitating the interaction of Ngb with cytochrome c in mitochondria. The present findings provided new insights into the neuroprotective mechanisms of hemin. It was concluded that low-dose hemin pretreatment had a neuroprotective effect in OGD-treated SH-SY5Y cells, through inhibiting cell apoptosis. The neuroprotective effects of hemin following hypoxic-ischemic neuronal damage were mainly mediated by Ngb. One underlying mechanism was hemin-induced overexpression of mitochondrial Ngb, which inhibited endogenous apoptosis via the association with cytochrome c.

Exercise affects biological characteristics of mesenchymal stromal cells derived from bone marrow and adipose tissue.

Both bone marrow mesenchymal stromal cells (BMSCs) and adipose-derived mesenchymal stromal cells (ADSCs) are good sources for tissue engineering. To maximize therapeutic efficacy of MSCs, an appropriate source of MSCs should be selected according to their own inherent characteristics for future clinical application. Hence, this study was conducted to compare proliferative, differential and antiapoptosis abilities of both MSCs derived from exercised and sedentary rats under normal and hypoxia/serum deprivation conditions (H/SD). Our results showed that exercise may enhance proliferative ability and decrease adipogenic ability of BMSCs and ADSCs. However, positive effect of exercise on osteogenesis was only observed for BMSCs in either environment. Little effect was observed on the antiapoptotic ability of both MSC types. It was also suggested that biological characteristics of both types were partly changed. It is therefore believed that BMSCs derived from exercised rat on early passage may be a good cell source for bone tissue engineering.

The dynamic change of serum S100B levels from day 1 to day 3 is more associated with sepsis-associated encephalopathy.

We investigated the role of dynamic changes of serum levels S100B protein in brain injury and poor outcome of sepsis. This is a prospective cohort study designed to include 104 adult patients with sepsis who are admitted to ICU from Jan 2015 to Aug 2016. Sepsis was defined as sepsis 3.0. Patients with a GCS score of <15, or at least one positive CAM-ICU score were thought to have brain dysfunction. 59 patients were diagnosed with SAE and the rest 45 patients were diagnosed with non-SAE. Serum S100B was measured on day 1 and 3 after ICU admission. Primary outcomes included brain dysfunction and 28-day/180-day mortality. The SAE group showed a significantly higher APACHE II score, SOFA scores, length of ICU stay, 28-day and 180-day mortality, serum S100B levels on day 1 and day 3. S100B levels on day 1 of 0.226 µg/L were diagnostic for SAE with 80.0% specificity and 66.1% sensitivity, and the area under (AUC) the curve was 0.728, S100B levels on day 3 of 0.144 µg/L were diagnostic for SAE with 84.44% specificity and 69.49% sensitivity, and the AUC was 0.819. In addition, the AUC for S100B on day 3 for predicting 180-day mortality was larger than for S100B on day 1 (0.731 vs. 0.611). Multiple logistic regression analysis showed that S100B3 (p = 0.001) but not S100B1 (p = 0.927) were independently correlated with SAE. Kaplan-Meier survival analysis showed that patients with S100B levels higher than 0.144 µg/L had a lower probability of survival at day 180. There were more patients with encephalopathy and a higher 28-day or 180-day mortality in the ΔS100B + group than in the ΔS100B- group. Multiple logistic regression analysis showed that SAE and IL-6 on day 3 were independently correlated with S100B dynamic increase. These findings suggest that elevated serum S100B levels on day 3 and the dynamic changes of serum S100B levels from day three to one were more associated with brain dysfunction and mortality than that on day 1 in patients with sepsis.

Mechanical Stretch Promotes the Osteogenic Differentiation of Bone Mesenchymal Stem Cells Induced by Erythropoietin.

INTRODUCTION: The effects of erythropoietin (EPO) on the behaviors of bone marrow mesenchymal stem cells (BMSCs) subjected to mechanical stretch remain unclear. This study was therefore aimed at establishing the dose-response effect of EPO stimulation on rat BMSCs and investigating the effects of mechanical stretch combined with EPO on the proliferation and osteogenic differentiation of BMSCs. MATERIAL AND METHODS: The proliferation and osteogenic differentiation of rat BMSCs were examined and compared using EPO with different concentrations. Thereafter, BMSCs were subjected to 10% elongation using a Flexcell strain unit, combined with 20 IU/ml EPO. The proliferation of BMSCs was detected by Cell Counting Kit-8, colony formation assay, and cell cycle assay; meanwhile, the mRNA expression levels of Ets-1, C-myc, Ccnd1, and C-fos were detected by reverse transcription and real-time quantitative PCR (qPCR). The osteogenic differentiation of BMSCs was detected by alkaline phosphatase (ALP) staining, and the mRNA expression levels of ALP, OCN, COL, and Runx2 were detected by qPCR. The role of the extracellular signal-regulated kinases 1/2 (ERK1/2) in the osteogenesis of BMSCs stimulated by mechanical stretch combined with 20 IU/ml EPO was examined by Western blot. RESULTS: Our results showed that effects of EPO on BMSCs included a dose-response relationship, with the 20 IU/ml EPO yielding the largest. Mechanical stretch combined with 20 IU/ml EPO promoted proliferation and osteogenic differentiation of BMSCs. The increase in ALP, mineral deposition, and osteoblastic genes induced by the mechanical stretch-EPO combination was inhibited by U0126, an ERK1/2 inhibitor. CONCLUSION: EPO was able to promote the proliferation and osteogenic differentiation of BMSCs, and these effects were enhanced when combined with mechanical stretch. The underlying mechanism may be related to the activation of the ERK1/2 signaling pathway.

Intensity-dependent effect of treadmill running on rat Achilles tendon.

It is understood that mechanical loading may affect tendon properties. However, how different mechanical loading conditions may affect tendons remains unknown. The present study aimed to investigate the effect of treadmill running at various intensities on rat Achilles tendon. A total of 18 male Wistar rats were randomly assigned to one of three groups: Control (CON), medium-intensity running (MIR), and high-intensity running (HIR). Following 8 weeks of treadmill running protocols, all Achilles tendons were harvested for histological observation and gene expression analysis. Significant morphological changes were observed with regular and large diameter collagen fibrils in the MIR group, whereas irregular and small diameter collagen fibrils were observed in the HIR group. Collagen type I was significantly upregulated in the MIR group compared with the CON group, and downregulated in the HIR group compared with the CON or MIR groups (P<0.05). However, collagen type III was significantly upregulated in the HIR group in comparison with the CON or MIR groups (P<0.05). Furthermore, the expression of matrix metallopeptidase-13 was significantly increased in the MIR and HIR groups compared with the CON group (P<0.05). The expression of tissue inhibitor of metalloproteinases-1 was increased in the MIR group compared with the CON group, but decreased in the HIR group compared with the CON and MIR groups (P<0.05). Additionally, decorin expression was significantly higher in the MIR group compared with the CON group, and significantly decreased in the HIR group compared with the CON or MIR groups (P<0.05). A converse pattern of changes in biglycan expression was identified among the three groups. Aggrecan expression was significantly higher in the HIR group compared with the CON or MIR groups (P<0.05). These findings indicated that moderate exercise may induce increased collagen synthesis and organize regular and large collagen fibers, thus benefiting the Achilles tendon. However, overuse during exercise may result in collagen degradation and disturbance, which predisposes individuals to injury.

Inhibiting the CD38/cADPR pathway protected rats against sepsis associated brain injury.

BACKGROUND: The CD38/cADPR pathway has been found to play roles in various inflammatory conditions. However, whether CD38 plays a protective or detrimental effect in the central nervous system (CNS) is controversial. The aim of this study was to determine the effect of CD38/cADPR pathway in sepsis associated brain injury. MATERIALS AND METHODS: Male Sprague-Dawley rats were undergone cecal ligation and puncture (CLP) or sham laparotomies. NAD+, cADPR and CD38 were measured in the hippocampus of septic rats at 0, 6, 12, 24, and 48h after CLP surgery. Rats were divided into the sham, CLP group, CLP+ CD38 expression lentivirus (CLP+ CD38 LV), CLP+ CD38 interference lentivirus (CLP+ CD38 Ri), CLP+ negative control lentivirus (CLP+NC) and the CLP+8-Br-cADPR groups. The Western blots of Bcl-2, Bax and iNOS, TUNEL assays, malondialdehyde (MDA) and superoxide dismutase (SOD) assays, transmission electron microscope analysis were performed in the hippocampus of rats. RESULTS: NAD+, cADPR and CD38 levels increased significantly in the hippocampus of septic rats as early as 12-24h after CLP surgery. CD38 knockdown or blocking cADPR with 8-Br-cADPR significantly reduced apoptosis, MDA and SOD activity, iNOS expression and ultrastructural morphology damages in the hippocampus of septic rats. CONCLUSIONS: In this study, we found that the CD38/cADPR pathway was activated in sepsis associated brain injury. Blocking this pathway protected the hippocampus from apoptosis, oxidative stress and ultrastructural morphology damages in septic rats.

Response of decorin to different intensity treadmill running.

Decorin is widely understood to affect collagen fibrillogenesis. However, little is understood about its response to various mechanical loading conditions. In the present study, 36 Wistar rats were randomly divided into control (CON), moderate treadmill running (MTR) and strenuous treadmill running (STR) groups. Animals in the MTR and STR groups were subjected to a 4­ or 8­week treadmill running protocol. Subsequently, all Achilles tendons were harvested to perform histological and biochemical analyses. Decorin expression was markedly increased in the MTR group compared with the CON group at 4 and 8 weeks. Conversely, decorin expression was markedly decreased in the STR group compared with the CON and MTR group at 4 and 8 weeks. Furthermore, between the two time points, decorin expression levels were significantly increased in the MTR group, whereas they were markedly decreased in the STR group. These results suggested that MTR exercise may induce increased decorin expression via a balance of MMP­2 and TIMP­2, improving tendon structure and function. However, STR exercise may result in degradation of decorin due to an imbalance of MMP­2 and TIMP­2, with a bias to MMP­2, resulting in a predisposition to tendinopathy.

MiR-451 suppresses proliferation, migration and promotes apoptosis of the human osteosarcoma by targeting macrophage migration inhibitory factor.

Previous studies have shown that MiR-451 plays an important role in human osteosarcoma carcinogenesis, but the underlying mechanism by which MiR-451 affects the osteosarcoma has not been fully understood. This study intends to uncover the mechanism by which MiR-451 functions as a tumor suppressor. The expression of MiR-451 in osteosarcoma tissues and osteosarcoma cell lines was monitored by real-time PCR. The proliferation ability was examined by MTT and cell cycle assay. The migration and apoptosis of cells were monitored by migration assay and flow cytometry, respectively. Moreover, the angiogenesis of HUVEC cells transfected with MiR-451 mimics was examined by tube formation assay. The effect of MiR-451 on MIF was determined by luciferase assays and Western blot assay. The results showed that MiR-451 expression level was significantly reduced in the osteosarcoma compared with normal bone tissues. Overexpression of MiR-451 significantly attenuated the proliferation and migration, and induced the apoptosis of osteosarcoma cells. Furthermore, the angiogenesis of HUVEC cells transfected with MiR-451 mimics was assayed and the decreased angiogenic ability was detected compared to the controls. Finally, we demonstrated that MiR-451 overexpression inhibited the malignant behavior of osteosarcoma by downregulating MIF. These findings suggest that MiR-451 may act as a tumor suppressor in osteosarcoma. MiR-451 inhibited cell proliferation, migration and angiogenesis and promoted apoptosis of human osteosarcoma cells, at least partially, by inhibiting the expression of MIF. MiR-451/MIF may be a novel therapeutic target in treatment of osteosarcoma.

Role of interferon regulatory factor-1 in lipopolysaccharide-induced mitochondrial damage and oxidative stress responses in macrophages.

Sepsis causes many early deaths; both macrophage mitochondrial damage and oxidative stress responses are key factors in its pathogenesis. Although the exact mechanisms responsible for sepsis-induced mitochondrial damage are unknown, the nuclear transcription factor, interferon regulatory factor-1 (IRF-1) has been reported to cause mitochondrial damage in several diseases. Previously, we reported that in addition to promoting systemic inflammation, IRF-1 promoted the apoptosis of and inhibited autophagy in macrophages. In the present study, we hypothesized that lipopolysaccharide (LPS)-induced IRF-1 activation in macrophages may promote mitochondrial damage and oxidative stress. In vitro, LPS was found to promote IRF-1 activation, reactive oxygen species (ROS) production, adenosine triphosphate (ATP) depletion, superoxide dismutase (SOD) consumption, malondialdehyde (MDA) accumulation and mitochondrial depolarization in macrophages in a time- and dose-dependent manner. These effects were abrogated in cells in which IRF-1 was knocked down. Furthermore, IRF-1 overexpression increased LPS-induced oxidative stress responses and mitochondrial damage. In vivo, peritoneal macrophages obtained from IRF-1 knockout (KO) mice produced less ROS and had less mitochondrial depolarization and damage following the administration of LPS, when compared to their wild-type (WT) counterparts. In addition, IRF-1 KO mice exhibited a decreased release of mitochondrial DNA (mtDNA) following the administration of LPS. Thus, IRF-1 may be a critical factor in augmenting LPS-induced oxidative stress and mitochondrial damage in macrophages.

Spatial and temporal changes of subchondral bone proceed to articular cartilage degeneration in rats subjected to knee immobilization.

This study was aimed to investigate the spatial and temporal changes of subchondral bone and its overlying articular cartilage in rats following knee immobilization. A total of 36 male Wistar rats (11-13 months old) were assigned randomly and evenly into 3 groups. For each group, knee joints in 6 rats were immobilized unilaterally for 1, 4, or 8 weeks, respectively, while the remaining rats were allowed free activity and served as external control groups. For each animal, femurs at both sides were dissected after sacrificed. The distal part of femur was examined by micro-CT. Subsequently, femoral condyles were collected for further histological observation and analysis. For articular cartilage, significant changes were observed only at 4 and 8 weeks of immobilization. The thickness of articular cartilage and chondrocytes numbers decreased with time. However, significant changes in subchondral bone were defined by micro-CT following immobilization in a time-dependent manner. Immobilization led to a thinner and more porous subchondral bone plate, as well as a reduction in trabecular thickness and separation with a more rod-like architecture. Changes in subchondral bone occurred earlier than in articular cartilage. More importantly, immobilization-induced changes in subchondral bone may contribute, at least partially, to changes in its overlying articular cartilage.