In vivo bioluminescence imaging revealed the change of the time window of BDNF expression in the brain elicited by a single bout of exercise following repeated exercise

Exercise increases the expression of brain-derived neurotrophic factor (BDNF) in the brain and contributes to cognitive and sensorimotor functions. This study aimed to elucidate how repeated exercise modifies BDNF expression elicited by a single bout of exercise in the brain using in vivo bioluminescence imaging (BLI). Bdnf-luciferase (Luc) mice with the firefly luciferase gene inserted at the translation start point of the Bdnf gene were used for BLI to monitor changes in BDNF expression in the brain. The treadmill exercise at a speed of 10 m/s for 60 min was repeated 5 days a week for 4 weeks. BLI in individual subjects was repeated four times: before the exercise intervention, on the first exercise day, and 14 and 28 days after the start of the intervention. Each BLI was performed after a single bout of exercise and monitored for 8 h after exercise. Repetitive BLI showed that the exercise regimen enhanced BDNF expression in the brain, specifically at 4-8 h after a single bout of exercise. Repeated exercise for 2 weeks accelerated the start of enhancement after a single bout of exercise, but not after 4 weeks of repeated exercise. This study showed that repeated exercise modulated the time window of exercise-enhanced BDNF expression, suggesting that repeated exercise could change the sensitivity of gene expression to a single bout of exercise. These findings can be attributed to the advantages of in vivo BLI, which allowed us to precisely measure the time course of BDNF expression after repeated exercise in individual subjects.

Temporal dynamics of brain BDNF expression following a single bout of exercise: A bioluminescence imaging study

Physical exercise increases brain-derived neurotrophic factor (BDNF) expression in the brain. However, the absence of non-invasive and repetitive monitoring of BDNF expression in the brains of living animals has limited the understanding of how BDNF expression changes after exercise. This study aimed to elucidate the temporal dynamics of BDNF expression in the brain after a single bout of exercise, using in vivo bioluminescence imaging. This study included Bdnf-Luc mice with a firefly Luciferase gene inserted at the translation start site of the mouse Bdnf gene. BDNF expression was evaluated based on the luminescence signal of the luciferase substrate administered to mice. Bioluminescence imaging was performed at 0, 1, 3, 6, 12, and 24 h after treadmill exercise (15 m/min for 1 h). Compared to the sedentary condition of each mouse, the luminescence signal increased by approximately 60 % between 1 and 3 h after exercise. The luminescence signal remained slightly increased by approximately 20 % even 6-24 h after exercise. This study is the first to demonstrate exercise-enhanced BDNF expression in the brains of living animals. These results provide evidence that a single bout of exercise transiently increases BDNF expression in the brain within a limited time window.

Analysis of the Anticipatory Behavior Formation Mechanism Induced by Methamphetamine Using a Single Hair

While the suprachiasmatic nucleus (SCN) coordinates many daily rhythms, some circadian patterns of expression are controlled by SCN-independent systems. These include responses to daily methamphetamine (MAP) injections. Scheduled daily injections of MAP resulted in anticipatory activity, with an increase in locomotor activity immediately prior to the time of injection. The MAP-induced anticipatory behavior is associated with the induction and a phase advance in the expression rhythm of the clock gene Period1 (Per1). However, this unique formation mechanism of MAP-induced anticipatory behavior is not well understood. We recently developed a micro-photomultiplier tube (micro-PMT) system to detect a small amount of Per1 expression. In the present study, we used this system to measure the formation kinetics of MAP-induced anticipatory activity in a single whisker hair to reveal the underlying mechanism. Our results suggest that whisker hairs respond to daily MAP administration, and that Per1 expression is affected. We also found that elevated Per1 expression in a single whisker hair is associated with the occurrence of anticipatory behavior rhythm. The present results suggest that elevated Per1 expression in hairs might be a marker of anticipatory behavior formation.

Poly(ADP-ribose) Polymerase (PARP) is Critically Involved in Liver Ischemia/reperfusion-injury

BACKGROUND

Poly(ADP-ribose) polymerase (PARP) is a DNA-repairing enzyme activated by extreme genomic stress, and therefore is potently activated in the remnant liver suffering from ischemia after surgical resection. However, the impact of PARP on post-ischemic liver injury has not been elucidated yet.

MATERIALS AND METHODS

We investigated the impact of PARP on murine hepatocyte/liver injury induced by hypoxia/ischemia, respectively.

RESULTS

PJ34, a specific inhibitor of PARP, markedly protected against hypoxia/reoxygenation (H/R)-induced cell death, though z-VAD-fmk, a pan-caspase inhibitor similarly showed the protective effect. PJ34 did not affect H/R-induced caspase activity or caspase-mediated cell death. z-VAD-fmk also did not affect the production of PAR (i.e., PARP activity). Therefore, PARP- and caspase-mediated cell death occurred in a mechanism independent of each other in H/R. H/R immediately induced activation of PARP and cell death afterwards, both of which were suppressed by PJ34 or Trolox, an antioxidant. This suggests that H/R-induced cell death occurred redox-dependently through PARP activation. H/R and OS induced nuclear translocation of apoptosis inducing factor (AIF, a marker of parthanatos) and RIP1-RIP3 interaction (a marker of necroptosis), both of which were suppressed by PJ34. H/R induced PARP-mediated parthanatos and necroptosis redox-dependently. In mouse experiments, PJ34 significantly reduced serum levels of AST, ALT & LDH and areas of hepatic necrosis after liver ischemia/reperfusion, similar to z-VAD-fmk or Trolox.

CONCLUSION

PARP, activated by ischemic damage and/or oxidative stress, may play a critical role in post-ischemic liver injury by inducing programmed necrosis (parthanatos and necroptosis). PARP inhibition may be one of the promising strategies against post-ischemic liver injury.

Period1 gene expression in the olfactory bulb and liver of freely moving streptozotocin-treated diabetic mouse

Clock genes express circadian rhythms in most organs. These rhythms are organized throughout the whole body, regulated by the suprachiasmatic nucleus (SCN) in the brain. Disturbance of these clock gene expression rhythms is a risk factor for diseases such as obesity. In the present study, to explore the role of clock genes in developing diabetes, we examined the effect of streptozotocin (STZ)-induced high glucose on Period1 (Per1) gene expression rhythm in the liver and the olfactory bub (OB) in the brain. We found a drastic increase of Per1 expression in both tissues after STZ injection while blood glucose content was low. After a rapid expression peak, Per1 expression showed no rhythm. Associated with an increase of glucose content, behavior became arrhythmic. Finally, we succeeded in detecting an increase of Per1 expression in mice hair follicles on day 1 after STZ administration, before the onset of symptoms. These results show that elevated Per1 expression by STZ plays an important role in the aggravation of diabetes.

Sample preparation method with ultrafiltration for whole blood thiosulfate measurement

Quantitative analysis of thiosulfate is useful for diagnosing hydrogen sulfide poisoning. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) enables more rapid and sensitive measurements than previous methodologies. As simple measurements of blood thiosulfate concentration are affected by the blood matrix, blood is used as the solvent to prepare the standard solution for calibration curve generation. Thus, a large amount of blood devoid of thiosulfate is required. We developed a preparation method by incorporating an ultrafiltration step to overcome this limitation and generate a calibration curve using a standard solution prepared with pure water. We used this improved method to investigate the stability of thiosulfate in refrigerated samples. To compare the effects of refrigeration, blood samples were prepared using the following two methods: one sample was treated with a 50-kDa exclusion ultrafiltration membrane and the other was not treated. The samples were stored at 4 °C, and then measured at 0, 3, 6, 24, 48, and 96 h. The incorporation of the ultrafiltration step in the measurement procedure enabled the quantification of thiosulfate, by plotting a calibration curve using a standard of pure water; it did not require a blood standard. Additionally, the reduction in whole blood thiosulfate concentration was within 10% during 2 days of refrigeration. Thus, the need for a large amount of blood to prepare the standard solution was resolved by the ultrafiltration step in test sample preparation. This method is useful to measure thiosulfate concentration and is not hindered by sample refrigeration for a few days.

Extracts of bilberry (Vaccinium myrtillus L.) fruits improve liver steatosis and injury in mice by preventing lipid accumulation and cell death

Bilberry has been reported to have anti-oxidant and anti-inflammatory properties. We studied the effect of bilberry (Vaccinium myrtillus L.) fruits extracts (BEs) on the pathogenesis caused by lipid accumulation in fatty liver and non-alcoholic steatohepatitis (NASH). 5 μg/ml of BEs was enough to suppress lipid accumulation in the fatty liver model of the mouse hepatic AML12 cells. BEs increased cell viability and anti-oxidant capacity, presumably by activating (phosphorylating) Akt/STAT3 and inducing MnSOD/catalase. BEs also significantly reduced Rubicon and induced p62/SQSTM1, possibly contributing to reduce cellular lipids (lipophagy). When the mice were fed supplemented with BEs (5% or 10%, w/w), hepatic steatosis, injury, and hypercholesterolemia/hyperglycemia were significantly improved. Furthermore, histological and cytokine studies indicated that BEs possibly suppress hepatic inflammation (hepatitis) and fibrosis. Therefore, BEs improved liver steatosis and injury, and potentially suppress fibrosis by suppressing inflammatory response, which therefore may prevent the progression of fatty liver to NASH.

Activation of caspase-3 during Chlamydia trachomatis-induced apoptosis at a late stage

The obligate intracellular bacterium Chlamydia trachomatis activates the host cell apoptosis pathway at a late stage of its developmental cycle. However, whether caspase-3, which is a key enzyme of apoptosis, is activated in Chlamydia-infected cells remains unknown. Here, we established HEp-2 cells stably expressing cFluc-DEVD, which is a caspase-3 substrate sequence inserted into cyclic firefly luciferase, and then monitored the dynamics of caspase-3 activity in cells infected with Chlamydia. Transfected cells without infection showed a significant increase in luciferase activity due to stimulation with staurosporine, an inducer of apoptosis. Activation was significantly blocked by addition of caspase inhibitor z-VAD-fmk. Furthermore, as expected, Chlamydia infection caused a significant increase in luciferase activation at 36-48 h postinfection with a contrastive decrease at 24 h postinfection, which is already well known. Such activation caused by the infection was much stronger when the amount of bacteria was increased. Thus, caspase-3 activation was accurately monitored by the luciferase activity in HEp-2 cells constitutively expressing the cFluc-DEVD probe. Furthermore, our data showed that C. trachomatis activates caspase-3 in host cells at a late stage of infection.

Photo-Activatable Akt Probe: A New Tool to Study the Akt-Dependent Physiopathology of Cancer Cells

Akt is commonly overexpressed and activated in cancer cells and plays a pivotal role in cell survival, protection, and chemoresistance. Therefore, Akt is one of the target molecules in understanding characters of cancer cells and developing anticancer drugs. Here we examined whether a newly developed photo-activatable Akt (PA-Akt) probe, based on a light-inducible protein interaction module of plant cryptochrome2 (CRY2) and cryptochrome-interacting basic helix–loop–helix (CIB1), can regulate Akt-associated cell functions. By illuminating blue light to the cells stably transfected with PA-Akt probe, CRY2-Akt (a fusion protein of CRY2 and Akt) underwent a structural change and interacted with Myr-CIBN (myristoylated N-terminal portion of CIB1), anchoring it at the cell membrane. Western blot analysis revealed that S473 and T308 of the Akt of probe-Akt were sequentially phosphorylated by intermittent and continuous light illumination. Endogenous Akt and GSK-3β, one of the main downstream signals of Akt, were also phosphorylated, depending on light intensity. These facts indicate that photo-activation of probe-Akt can activate endogenous Akt and its downstream signals. The photo-activated Akt conferred protection against nutritional deprivation and H₂O₂ stresses to the cells significantly. Using the newly developed PA-Akt probe, endogenous Akt was activated easily, transiently, and repeatedly. This probe will be a unique tool in studying Akt-associated specific cellular functions in cancer cells and developing anticancer drugs.

Changes in the expression of α-tocopherol-related genes in liver and mammary gland biopsy specimens of peripartum dairy cows

Blood α-tocopherol (α-Toc) concentrations decline gradually throughout the prepartum period, reaching the nadir after calving in dairy cows. The 6 α-Toc-related molecules [α-Toc transfer protein (TTPA); afamin; scavenger receptor class B, Type I; ATP-binding cassette transporter A1; tocopherol-associated protein (SEC14L2); and cytochrome P450 family 4, subfamily F, polypeptide 2 (CYP4F2)] are expressed in liver and other peripheral tissues. These molecules could regulate α-Toc transport, blood concentrations, and metabolism of α-Toc. Therefore, the aim of this study was to evaluate the changes in the expression of α-Toc-related genes in liver and mammary gland tissues of dairy cows around calving, which have remained elusive until now. In experiment (Exp.) 1, 28 multiparous Holstein cows were used (from -5 to 6 wk relative to parturition) to monitor the changes in dietary α-Toc intake, blood concentrations of α-Toc, and lipoproteins; in Exp. 2, 7 peripartum Holstein cows were used (from -4 to 4 wk relative to parturition) for liver tissue biopsy; and in Exp. 3, 10 peripartum Holstein cows were used (from -8 to 6 wk relative to parturition) to carry out the mammary gland tissue biopsy and milk sampling. In Exp. 1, the serum α-Toc concentrations declined gradually with decreasing amount of α-Toc intake and plasma high-density lipoprotein concentrations toward calving time. However, in the early lactation period after calving, serum α-Toc concentrations remained at a lower concentration despite the recovery of α-Toc intake and plasma high-density lipoprotein concentrations. In Exp. 2, just after calving, the TTPA, SEC14L2, afamin, and albumin mRNA expression levels in the liver were temporarily downregulated, and the hepatic mRNA levels of endoplasmic reticulum stress-induced unfolded protein response markers and acute-phase response marker increased at calving. In Exp. 3, the concentrations of α-Toc in colostrum were greater than those in precolostrum (samples were collected at wk -1 relative to parturition) and mature milk. The expression of TTPA, SEC14L2, and CYP4F2 mRNA in bovine mammary gland tissue was detected. However, TTPA and SEC14L2 mRNA expressions showed the opposite trends: the expression levels of TTPA mRNA peaked whereas SEC14L2 mRNA reached a nadir at calving. These results indicate that the expression of α-Toc-related genes involved in specific α-Toc transfer and metabolism in the liver and mammary gland are altered during calving. Moreover, these changes might be associated with the maintenance of lower serum α-Toc concentrations after calving.

Detection of Necroptosis in Ligand-Mediated and Hypoxia-Induced Injury of Hepatocytes Using a Novel Optic Probe-Detecting Receptor-Interacting Protein (RIP)1/RIP3 Binding

Liver injury is often observed in various pathological conditions including posthepatectomy state and cancer chemotherapy. It occurs mainly as a consequence of the combined necrotic and apoptotic types of cell death. In order to study liver/hepatocyte injury by the necrotic type of cell death, we studied signal-regulated necrosis (necroptosis) by developing a new optic probe for detecting receptor-interacting protein kinase 1 (RIP)/RIP3 binding, an essential process for necroptosis induction. In the mouse hepatocyte cell line, TIB-73 cells, TNF-α/cycloheximide (T/C) induced RIP1/3 binding only when caspase activity was suppressed by the caspase-specific inhibitor z-VAD-fmk (zVAD). T/C/zVAD-induced RIP1/3 binding was inhibited by necrostatin-1 (Nec-1), an allosteric inhibitor of RIP1. The reduced cell survival by T/C/zVAD was improved by Nec-1. These facts indicate that T/C induces necroptosis of hepatocytes when the apoptotic pathway is inhibited/unavailable. FasL also induced cell death, which was only partially inhibited by zVAD, indicating the possible involvement of necroptosis rather than apoptosis. FasL activated caspase 3 and, similarly, induced RIP1/3 binding when the caspases were inactivated. Interestingly, FasL-induced RIP1/3 binding was significantly suppressed by the antioxidants Trolox and N-acetyl cysteine (NAC), suggesting the involvement of reactive oxygen species (ROS) in FasL-induced necroptotic cellular processes. H₂O₂, by itself, induced RIP1/3 binding that was suppressed by Nec-1, but not by zVAD. Hypoxia induced RIP1/3 binding after reoxygenation, which was suppressed by Nec-1 or by the antioxidants. Cell death induced by hypoxia/reoxygenation (H/R) was also improved by Nec-1. Similar to H₂O₂, H/R did not require caspase inhibition for RIP1/3 binding, suggesting the involvement of a caspase-independent mechanism for non-ligand-induced and/or redox-mediated necroptosis. These data indicate that ROS can induce necroptosis and mediate the FasL- and hypoxia-induced necroptosis via a molecular mechanism that differs from a conventional caspase-dependent pathway. In conclusion, necroptosis is potentially involved in liver/hepatocyte injury induced by oxidative stress and FasL in the absence of apoptosis.

Relevance of FXR-p62/SQSTM1 pathway for survival and protection of mouse hepatocytes and liver, especially with steatosis

Background

Liver injury and regeneration involve complicated processes and are affected by various physio-pathological conditions. Surgically, severe liver injury after surgical resection often leads to fatal liver failure, especially with some underlying pathological conditions such as steatosis. Therefore, protection from the injury of hepatocytes and liver is a serious concern in various clinical settings.

Methods

We studied the effects of the farnesoid X receptor (FXR) on cell survival and steatosis in mouse hepatocytes (AML12 mouse liver cells) and investigated their molecular mechanisms. We next studied whether or not FXR improves liver injury, regeneration and steatosis in a mouse model of partial hepatectomy (PH) with steatosis.

Results

An FXR-specific agonist, GW4064, induced expressions of the p62/SQSTM1 gene and protein in AML12 mouse liver cells. Because we previously reported p62/SQSTM1 as a key molecule for antioxidation and cell survival in hepatocytes, we next examined the activation of nuclear factor erythroid 2-related factor-2 (Nrf2) and induction of the antioxidant molecules by GW4064. GW4064 activated Nrf2 and subsequently induced antioxidant molecules (Nrf2, catalase, HO-1, and thioredoxin). We also examined expressions of pro-survival and cell protective molecules associated with p62/SQSTM1. Expectedly, GW4064 induced phosphorylation of Akt, expression of the anti-apoptotic molecules (Bcl-xL and Bcl-2), and reduced harmful hepatic molecules (Fas ligand and Fas). GW4064 promoted hepatocyte survival, which was cancelled by p62/SQSTM1 siRNA. These findings suggest the potential relevance of the FXR-p62/SQSTM1 pathway for the survival and protection of hepatocytes. Furthermore, GW4064 induced the expression of small heterodimer partners (SHP) and suppressed liver X receptor (LXR)-induced steatosis in hepatocytes, expecting the in vivo protective effect of FXR on liver injury especially with steatosis. In the hepatectomy model of db/db mice with fatty liver, pre-treatment by GW4064 significantly reduced post-PH liver injury (serum levels of LDH, AST & ALT and histological study) and improved steatosis. The key molecules, p62/SQSTM1, Nrf2 and SHP were upregulated in fatty liver tissue by GW4064 treatment.

Conclusions

The present study is the first to demonstrate the relevance of FXR-p62/SQSTM1 and -SHP in the protection against injury of hepatocytes and post-PH liver, especially with steatosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-016-0568-3) contains supplementary material, which is available to authorized users.

Postweaning changes in the expression of chemerin and its receptors in calves are associated with the modification of glucose metabolism

Chemerin, originally known as a chemoattractant derived from adipose tissue and the liver, has been reported to have regulatory functions in gluconeogenesis, peripheral insulin sensitivity, and insulin secretion. This study was conducted to assess the postweaning changes in expression of this cytokine and its physiological role in the modification of glucose metabolism associated with weaning. Eighteen tissue samples were collected from Holstein calves (90 d of age; n = 4) to investigate the tissue distributions of chemerin and its receptors genes. was highly expressed in the liver, and secreted chemerin protein was found in the plasma. Among the receptors of chemerin, and were ubiquitously expressed whereas was predominantly expressed in the liver. The changes in glucose metabolism and expression of these genes after weaning were assessed by comparing suckling calves (n = 6) and weaned calves (n = 8) of Japanese Black cattle. No significant difference was observed in plasma glucose levels between suckling and weaned calves (P = 0.22), whereas the plasma level of total ketone bodies was significantly higher in weaned calves (P < 0.01). Plasma levels of insulin and cortisol did not differ between suckling and weaned calves. The mRNA levels of certain key enzymes involved in hepatic gluconeogenesis were also altered; for instance, level was lower in postweaning calves (P < 0.05) and () level tended to be higher after weaning (P = 0.08). However, was not altered after weaning. The plasma levels of hepatic stress indicators were also changed, with aspartate transaminase, alanine transaminase, and lactate dehydrogenase being significantly elevated in postweaning calves (P < 0.05). Chemerin protein in liver tissue was less abundant in weaned calves (P < 0.05), although there were no changes in its transcript levels. The abundance of plasma chemerin protein did not change after weaning (P = 0.95). In summary, these data indicate that as a consequence of weaning, which causes physiological stress and alters hepatic metabolism, chemerin protein expression within the liver is downregulated, indicating that chemerin plays a role in the upregulation of hepatic expression via its inhibitory effect on hepatic gluconeogenesis.

Cluster randomized trial to evaluate the impact of team training on surgical outcomes

Background

The application of safety principles from the aviation industry to the operating room has offered hope in reducing surgical complications. This study aimed to assess the impact on major surgical complications of adding an aviation-based team training programme after checklist implementation.

Methods

A prospective parallel-group cluster trial was undertaken between September 2011 and March 2013. Operating room teams from 31 hospitals were assigned randomly to participate in a team training programme focused on major concepts of crew resource management and checklist utilization. The primary outcome measure was the occurrence of any major adverse event, including death, during the hospital stay within the first 30 days after surgery. Using a difference-in-difference approach, the ratio of the odds ratios (ROR) was estimated to compare changes in surgical outcomes between intervention and control hospitals.

Results

Some 22 779 patients were enrolled, including 5934 before and 16 845 after team training implementation. The risk of major adverse events fell from 8·8 to 5·5 per cent in 16 intervention hospitals (adjusted odds ratio 0·57, 95 per cent c.i. 0·48 to 0·68; P &lt; 0·001) and from 7·9 to 5·4 per cent in 15 control hospitals (odds ratio 0·64, 0·50 to 0·81; P &lt; 0·001), resulting in the absence of difference between arms (ROR 0·90, 95 per cent c.i. 0·67 to 1·21; P = 0·474). Outcome trends revealed significant improvements among ten institutions, equally distributed across intervention and control hospitals.

Conclusion

Surgical outcomes improved substantially, with no difference between trial arms. Successful implementation of an aviation-based team training programme appears to require modification and adaptation of its principles in the context of the the surgical milieu. Registration number: NCT01384474 (http://www.clinicaltrials.gov).

Development for the measurement of serum thiosulfate using LC-MS/MS in forensic diagnosis of H2S poisoning

Thiosulfate measurement is crucial to diagnosis of hydrogen sulfide (H2S) poisoning in forensic toxicology. Although GC-MS method is currently regarded as a standard thiosulfate measurement, it requires complicated sample preparation prior to analysis. This study presents a simple, rapid, and highly sensitive method for the quantitative analysis of serum thiosulfate by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). This method is based on selected reaction monitoring and has high sensitivity with a lower quantification limit of 0.5μM. Precision and accuracy of this method meet the basic requirements for quantitative analysis (intra- and inter-day tests have a relative standard deviation of ⩽10.4%; range of analytical recovery is 94.3-102.6%). On the measurements of serum thiosulfate by our developed method, a thiosulfate concentration as 57.5μM was detected clearly in the H2S poisoning case comparing to the non poisoning case in which only a trace amount of thiosulfate was observed.

Inflammatory responses increase secretion of MD-1 protein

Radioprotective 105 (RP105) is a type I transmembrane protein, which associates with a glycoprotein, MD-1. Monoclonal antibody (mAb)-mediated ligation of RP105/MD-1 robustly activates B cells. RP105/MD-1 is structurally similar to Toll-like receptor 4 (TLR4)/MD-2. B-cell responses to TLR2 and TLR4/MD-2 ligands are impaired in the absence of RP105 or MD-1. In addition to RP105/MD-1, MD-1 alone is secreted. The structure of MD-1 shows that MD-1 has a hydrophobic cavity that directly binds to phospholipids. Little is known, however, about a ligand for MD-1 and the role of MD-1 in vivo To study the role of RP105/MD-1 and MD-1 alone, specific mAbs against MD-1 are needed. Here, we report the establishment and characterization of two anti-MD-1 mAbs (JR2G9, JR7G1). JR2G9 detects soluble MD-1, whereas JR7G1 binds both soluble MD-1 and the cell surface RP105/MD-1 complex. With these mAbs, soluble MD-1 was detected in the serum and urine. The MD-1 concentration was altered by infection, diet and reperfusion injury. Serum MD-1 was rapidly elevated by TLR ligand injection in mice. The quantitative PCR and supernatant-precipitated data indicate that macrophages are one of the sources of serum soluble MD-1. These results suggest that soluble MD-1 is a valuable biomarker for inflammatory diseases.

Clinical Significance of the Champagne Bottle Neck Sign in the Extracranial Carotid Arteries of Patients with Moyamoya Disease

BACKGROUND AND PURPOSE

The champagne bottle neck sign represents a rapid reduction in the extracranial ICA diameters and is a characteristic feature of Moyamoya disease. However, the clinical significance of the champagne bottle neck sign is unclear. We investigated the relationship between the champagne bottle neck sign and the clinical and hemodynamic stages of Moyamoya disease.

MATERIALS AND METHODS

We analyzed 14 patients with Moyamoya disease before revascularization (5 men, 9 women; age, 43.2 ± 19.3 years). The ratio of the extracranial ICA and common carotid artery diameters was determined using carotid ultrasonography or cerebral angiography; a ratio of < 0.5 was considered champagne bottle neck sign-positive. The clinical disease stage was determined using the Suzuki angiographic grading system. CBF and cerebral vasoreactivity also were measured.

RESULTS

The ICA/common carotid artery ratio (expressed as median [interquartile range]) decreased as the clinical stage advanced (stages I-II, 0.71 [0.60-0.77]; stages III-IV, 0.49 [0.45-0.57]; stages V-VI, 0.38 [0.34-0.47]; P < .001). Lower ICA/common carotid artery ratio tended to occur in symptomatic versus asymptomatic arteries (0.47 [0.40-0.53] versus 0.57 [0.40-0.66], respectively; P = .06). Although the ICA/common carotid artery ratio was not related to cerebral perfusion, it decreased as cerebral vasoreactivity decreased (P < .01). All champagne bottle neck sign-positive arteries were classified as Suzuki stage ≥III, 73% were symptomatic, and 89% exhibited reduced cerebral vasoreactivity. In contrast, all champagne bottle neck sign-negative arteries were Suzuki stage ≤III, 67% were asymptomatic, and all showed preserved cerebral vasoreactivity.

CONCLUSIONS

The champagne bottle neck sign was related to advanced clinical stage, clinical symptoms, and impaired cerebral vasoreactivity. Thus, detection of the champagne bottle neck sign might be useful in determining the clinical and hemodynamic stages of Moyamoya disease.

Growth arrest and DNA damage-inducible 34 regulates liver regeneration in hepatic steatosis in mice

The liver has robust regenerative potential in response to damage, but hepatic steatosis (HS) weakens this potential. We found that the enhanced integrated stress response (ISR) mediated by phosphorylation of the alpha subunit of eukaryotic initiation factor 2 (eIF2α) impairs regeneration in HS and that growth arrest and DNA damage-inducible 34 (Gadd34)-dependent suppression of ISR plays a crucial role in fatty liver regeneration. Although mice fed a high-fat diet for 2 weeks developed moderate fatty liver with no increase in eIF2α phosphorylation before 70% hepatectomy, they showed impaired liver regeneration as a result of reduced proliferation and increased death of hepatocytes with increased phosphorylation of eIF2α and ISR. An increased ISR through Gadd34 knockdown induced C/EBP homologous protein (CHOP)-dependent apoptosis and receptor-interacting protein kinase 3-dependent necrosis, resulting in increased hepatocyte death during fatty liver regeneration. Furthermore, Gadd34 knockdown and increased phosphorylation of eIF2α decreased cyclin D1 protein and reduced hepatocyte proliferation. In contrast, enhancement of Gadd34 suppressed phosphorylation of eIF2α and reduced CHOP expression and hepatocyte apoptosis without affecting hepatocyte proliferation, clearly improving fatty liver regeneration. In more severe fatty liver of leptin receptor-deficient db/db mice, forced expression of hepatic Gadd34 also promoted hepatic regeneration after hepatectomy.

CONCLUSION

Gadd34-mediated regulation of ISR acts as a physiological defense mechanism against impaired liver regeneration resulting from steatosis and is thus a possible therapeutic target for impaired regeneration in HS.

p62/SQSTM1 plays a protective role in oxidative injury of steatotic liver in a mouse hepatectomy model

AIMS

Liver injury and regeneration involve complicated processes and are affected by various physio-pathological factors. We investigated the mechanisms of steatosis-associated liver injury and delayed regeneration in a mouse model of partial hepatectomy.

RESULTS

Initial regeneration of the steatotic liver was significantly delayed after hepatectomy. Although hepatocyte proliferation was not significantly suppressed, severe liver injury with oxidative stress (OS) occurred immediately after hepatectomy in the steatotic liver. Fas-ligand (FasL)/Fas expression was upregulated in the steatotic liver, whereas the expression of antioxidant and anti-apoptotic molecules (catalase/MnSOD/Ref-1 and Bcl-2/Bcl-xL/FLIP, respectively) and p62/SQSTM1, a steatosis-associated protein, was downregulated. Interestingly, pro-survival Akt was not activated in response to hepatectomy, although it was sufficiently expressed even before hepatectomy. Suppression of p62/SQSTM1 increased FasL/Fas expression and reduced nuclear factor erythroid 2-related factor-2 (Nrf-2)-dependent antioxidant response elements activity and antioxidant responses in steatotic and nonsteatotic hepatocytes. Exogenously added FasL induced severe cellular OS and necrosis/apoptosis in steatotic hepatocytes, with only the necrosis being inhibited by pretreatment with antioxidants, suggesting that FasL/Fas-induced OS mainly leads to necrosis. Furthermore, p62/SQSTM1 re-expression in the steatotic liver markedly reduced liver injury and improved liver regeneration.

INNOVATION

This study is the first which demonstrates that reduced expression of p62/SQSTM1 plays a crucial role in posthepatectomy acute injury and delayed regeneration of steatotic liver, mainly via redox-dependent mechanisms.

CONCLUSION

In the steatotic liver, reduced expression of p62/SQSTM1 induced FasL/Fas overexpression and suppressed antioxidant genes, mainly through Nrf-2 inactivation, which, along with the hypo-responsiveness of Akt, caused posthepatectomy necrotic/apoptotic liver injury and delayed regeneration, both mainly via a redox-dependent mechanism.

Contribution of toll-like receptor 2 to the innate response against Staphylococcus aureus infection in mice

Staphylococcus aureus is a common pathogen that causes a wide range of infectious diseases. The function of TLRs, specifically TLR2, during S. aureus infection is still debated. In this study, we investigated the extent to which TLR2 contributes to the host innate response against the bacterial infection using TLR2-deficient mice. Intravenous inoculation with S. aureus resulted in all TLR2-deficient mice dying within 4 d, along with a high bacterial burden in the livers. However, histological examination showed the same degree of macrophage and neutrophil accumulation in the livers of infected TLR2-deficient mice as that in infected wild-type (WT) mice. TLR2-deficient mouse macrophages also showed normal phagocytic activity, although they failed to express CD36 that appeared on the surface of WT mouse cells upon challenge with heat-killed S. aureus. These data indicate that TLR2, as well as CD36, does not directly affect S. aureus clearance and that CD36 expression on macrophages depends on the presence of TLR2. In vivo infection with S. aureus caused significantly elevated production of TNF-α and IL-6 in the livers and blood of TLR2-deficient mice compared with those in WT mice, while the hepatic and serum levels of IL-10 decreased in these mice. In contrast, lower expression of IL-6 and IL-10, but not of TNF-α, at both the gene and protein levels was found in TLR2-deficient mouse macrophages compared to that in WT mouse cells, in response to challenge with heat-killed S. aureus. These findings suggest that the S. aureus-induced pro-inflammatory cytokine response is not dependent on macrophages and that TLR2 deficiency results in decreased IL-10 release by macrophages, which contributes to dysregulated cytokine balance, impaired bacterial clearance, and mouse death. Therefore, TLR2 possesses a protective function during S. aureus infection by regulating pro- and anti-inflammatory cytokine responses.

A high-protein diet induces dissociation between plasma concentrations of growth hormone and ghrelin in wethers

High-carbohydrate or high-fat diets have been demonstrated to change ghrelin concentrations in plasma; however, there remains a need to clarify the effects of dietary protein on the interaction between circulating GH and ghrelin concentrations in the ruminant. In this study, we investigated the postprandial changes in plasma concentrations of GH and ghrelin and their interactions when wethers were fed either a high-protein (HP; 40% CP) or a low-protein (LP; 10% CP) diet for 2 wk. The wethers were divided into 2 groups and fed once a day for 2 wk in a randomized crossover design. Each diet contained the same level of ME. Blood was collected from the animals at specific times over 24 h to measure hormones and metabolites. Feeding once a day caused a prompt reduction in the GH and ghrelin concentrations regardless of the type of diet that the wethers consumed. The preprandial concentrations (P = 0.04), area under the curve (AUC; P = 0.04), and incremental AUC (iAUC; P = 0.06) for ghrelin in HP-fed wethers were or tended to be greater than those in LP-fed wethers although concentrations for GH were the same for both diets (P = 0.23). In addition, the time it took for the postprandial ghrelin concentrations to recover to the preprandial concentrations was greater in HP-fed wethers than in LP-fed wethers although this was not true for GH concentrations. Similarly, as for ghrelin, postprandial increase (P < 0.001) and AUC (P = 0.03) for insulin concentration was greater in the HP-fed wethers than in the LP-fed wethers. From these findings, we concluded that dietary proteins (or some other derived metabolites) may dissociate the interaction between plasma concentrations of GH and ghrelin in wethers.

Successful transplantation of rat hearts subjected to extended cold preservation with a novel preservation solution

Since prolonged cold preservation of the heart deteriorates the outcome of heart transplantation, a more protective preservation solution is required. We therefore developed a new solution, named Dsol, and examined whether Dsol, in comparison to UW, could better inhibit myocardial injury resulting from prolonged cold preservation. Syngeneic heterotopic heart transplantation in Lewis rats was performed after cold preservation with UW or Dsol for 24 or 36 h. In addition to graft survival, myocardial injury, ATP content, and Ca(2+) -dependent proteases activity were assessed in the 24-h preservation group. The cytosolic Ca(2+) concentration of H9c2 cardiomyocytes after 24-h cold preservation was assessed. Dsol significantly improved 7-day graft survival after 36-h preservation. After 24-h preservation, Dsol was associated with significantly faster recovery of ATP content and less activation of calpain and caspase-3 after reperfusion. Dsol diminished graft injury significantly, as revealed by the lower levels of infarction, apoptosis, serum LDH and AST release, and graft fibrosis at 7-day. Dsol significantly inhibited Ca(2+) overload during cold preservation. Dsol inhibited myocardial injury and improved graft survival by suppressing Ca(2+) overload during the preservation and the activation of Ca(2+) -dependent proteases. Dsol is therefore considered a better alternative to UW to ameliorate the outcome of heart transplantation.

In vivo monitoring of liver damage using caspase-3 probe

Real-time monitoring of cellular and organ conditions improves our understanding of various physiopathological phenomena. Such monitoring is expected to provide important alternatives for clinical diagnosis and therapy. We have sought to show physiopathological changes of organs as well as cells. Here, we present an example of in vivo imaging of liver states using the luciferase-based caspase-3 optical probe. We examined dynamic changes of apoptosis (caspase-3 activity) of a mouse liver as well as those of liver cells, proving that the emitted signals reflected the biochemically evaluated apoptotic cell death. In live liver cell (AML 12) experiments, the optical probe for caspase-3 activity emitted signals in response to Fas-ligand, staurosporine and hypoxia/reoxygenation, demonstrating that the probe can measure cellular apoptosis quantitatively. We therefore applied this probe for mouse liver ischemia/reperfusion (I/R) and drug-toxicity to liver. By expressing the probe in a mouse liver adenovirally, we imaged liver caspase-3 activity (i.e. apoptotic damage) non-invasively and chronologically in the hepatic I/R model of mice. The duration of liver ischemia affected the post-ischemic caspase-dependent damage. Ischemia (up to 60 min) enhanced liver damage after reperfusion, but prolonged ischemia (90 min of ischemia) induced not apoptotic cell death but necrotic cell death. Direct observations of the changes of organ conditions elucidated the dynamism of organ function and damage. These technologies clearly possess clinical relevance. They are expected to provide a new diagnostic tool for various clinical settings in the future.

Navigation of sentinel node biopsy and selective axillary dissection using 3D-CT mammary lymphography with the arm lymph flow enhancement

98

Background: In early breast cancer, the presence of metastasis in axillary lymph nodes (AN) is an important factor in prognosis and further treatment. However, AN dissection causes many complications such as contracture of shoulder joint, lymph edema, and paralysis of upper extremities. Sentinel node (SN) biopsy provides us a valuable information about no need to dissect AN for node-negative patients. However, on node-positive patients, the conventional AN dissection has been performed. 3D-CT lymphography (LG) can show the precise individual lymphatic flow not only from the breast tumor to SN but also from SN to venous angle, which means breast lymphatic channel. We applied 3D-CT LG to distinguish them from the arm channel to avoid any arm complications.

Methods: 3D-CT LG was performed before surgery to mark SN on the skin. Above the tumor and near the areola and the arm pit, 2 ml of iopamidol 300 was injected subcutaneously. Images of CT scan were taken at 1, 3, and 10 min after injection. They were reconstructed to produce a 3D image of lymph ducts and lymph nodes by the volume rendering software. The axillary node groups were classified to 5 groups as described before. The arm lymph channel was classified to 4 regions. SN biopsy and AN sampling were performed by dye-staining method using endoscopy.

Results: We have performed 3D-CT LG on 200 patients and evaluated the arm lymph flow on 50 patients. The average age was 55.1 years old. The average tumor size was 2.4 cm. The average sampled number of SN was 2.3. The arm lymph channels were observed at 10 minutes after injection. They were divided into four directions: around and above the axillary vein (64%), the axilla (12%), the supraclavicule (8%), and the lateral chest (16%). The connection between the breast and the arm channel was observed in each five groups of axillary nodes shown by 3D-CT LG. We could detect their position on the axillary lymphatic mapping by 3D-CT LG during surgery. The selective axillary dissection can be performed by avoiding the arm lymph channel.

Conclusions: The arm lymph channel can be observed by 3D-CT LG with the arm enhancement, which will help the selective axillary dissection to prevent the arm lymph edema.

Inhibition of nuclear factor-kappaB suppresses peritoneal dissemination of gastric cancer by blocking cancer cell adhesion

Currently, patients with peritoneal dissemination of gastric cancer must accept a poor prognosis because there is no standard effective therapy. To inhibit peritoneal dissemination it is important to inhibit interactions between extracellular matrices (ECM) and cell surface integrins, which are important for cancer cell adhesion. Although nuclear factor-kappa B (NF-κB) is involved in various processes in cancer progression, its involvement in the expression of integrins has not been elucidated. We used a novel NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), to study whether NF-κB blocks cancer cell adhesion via integrins in a gastric cancer dissemination model in mice and found that DHMEQ is a potent suppressor of cancer cell dissemination. Dehydroxymethylepoxyquinomicin suppressed the NF-κB activity of human gastric cancer cells NUGC-4 and 44As3Luc and blocked the adhesion of cancer cells to ECM when compared with the control. Dehydroxymethylepoxyquinomicin also inhibited expression of integrin (α2, α3, β1) in in vitro studies. In the in vivo model, we injected 44As3Luc cells pretreated with DHMEQ into the peritoneal cavity of mice and performed peritoneal lavage after the injection of cancer cells. Viable cancer cells in the peritoneal cavities were evaluated sequentially by in vivo imaging. In mice injected with DHMEQ-pretreated cells and lavaged, live cancer cells in the peritoneum were significantly reduced compared with the control, and these mice survived longer. These results indicate that DHMEQ could inhibit cancer cell adhesion to the peritoneum possibly by suppressing integrin expression. Nuclear factor-kappa B inhibition may be a new therapeutic option for suppressing postoperative cancer dissemination.

Hepatic ischemia induced immediate oxidative stress after reperfusion and determined the severity of the reperfusion-induced damage

Noninvasive evaluation of organ redox states provides invaluable information in many clinical settings. We evaluated a newly developed reduction/oxidation-sensitive green fluorescent protein (roGFP) probe that reports cellular redox potentials and their dynamic changes in live cells. On hypoxia/reoxygenation (H/R) of AML12 liver cells, roGFP indicated mild reduction during hypoxia, but immediate transient oxidation after reoxygenation. The roGFP probe confirmed the antioxidative effects of N-acetylcysteine, catalase, redox factor-1, and Mn-SOD/CuZn-SOD against H/R-induced cellular oxidative stress (OS). In a mouse liver ischemia/reperfusion (I/R) model, roGFP transduced by using an adenoviral vector revealed immediate reduction of the liver under ischemia, and two distinct peaks of OS: (a) early, observed within 60 min after reperfusion, similar to the in vitro study; and (b) later, at 24 h. The early peak levels paralleled the ischemic time up to 75 min and the postischemic liver injury (sGOT/GPT/LDH) in the later phase (6 and 24 h after I/R). The roGFP probe successfully indicated postischemic OS of the liver in living mice, accurately predicting postischemic liver injury. This probe may represent an effective OS marker indicating organ redox states and also predicting the damage/function.

Sentinel and axillary nodes of the breast distinguished from those of the arm by 3D-CT lymphography and selectively dissected by endoscopic surgery

616

Background: In early breast cancer, the presence of metastasis in axillary lymph nodes (AN) is an important factor in prognosis and further treatment. However, AN dissection causes many complications such as contracture of shoulder joint, lymph edema, and paralysis of upper extremities. Sentinel node (SN) biopsy provides us valuable information about no need to dissect AN for node-negative patients. However, on node-positive patients, the conventional AN dissection has been performed. 3D-CT lymphography (LG) can show the precise individual lymphatic flow not only from the breast tumor to SN but also from SN to venous angle, which means breast lymphatic channel. We applied 3D-CT LG to distinguish them from the arm channel to avoid any arm complications. Methods: 3D-CT LG was performed on the day before surgery to mark SN on the skin. Above the tumor and near the areola and the arm pit, 2 ml of Iopamidol 300 was injected subcutaneously. Images of 16-channel multidetector-row helical CT scan were taken at 1, 3, and 5 min after injection. They were reconstructed to produce a 3D image of lymph ducts and lymph nodes. SN biopsy and AN sampling were performed by dye-staining method using endoscopy. Results:We performed SN biopsy with 3D-CT LG on 160 patients. 3D-CT LG clearly showed the precise lymphatic flow from the tumor to SN. It can show SN at only one min after injection. But following up to 5 min, we can follow the lymph ducts beyond SN into the second to the fifth node groups toward the venous angle with complex plexus, observed in the surrounding anatomical architecture. Detection rate was 100% for SN; 80% for the third group; and 30% for the fifth group. The arm lymph flow was distinguished by the connections between the breast and the arm flow, observed 39% and 71% in the fourth and the fifth group. SN was shared from between the breast and the arm in 5 patients (3.1%). They complained arm edema only by SN biopsy. We can distinguish and sample AN drained from the breast, guided by 3D-CT LG and dye-staining using endoscopy. Conclusions:By 3D-CT LG, we can recognize the accurate and more precise lymph flow in the surrounding anatomical architecture. It helps us easily to pursuit lymph flow and to remove SN and AN from the breast selectively using endoscopic surgery.

No significant financial relationships to disclose.

Selective axillary node dissection differed from the arm lymph flow oriented by 3D-CT lymphography

Abstract #1012

Background: In early breast cancer, the presence of metastasis in axillary lymph nodes is an important factor in prognosis and further treatment. However, axillary node dissection causes many complications such as contracture of the shoulder joint, lymph edema, and paralysis of the upper extremities. Sentinel node (SN) biopsy provides us an information about no need to dissect axillary nodes for node-negative patients. But on node-positive patients, the conventional axillary node dissection has been performed. 3D-CT lymphography (LG) can show the precise individual lymphatic flow not only from the tumor to SN but also from SN to venous angle, which means breast lymphatic channel. We applied 3D-CT LG to distinguish them from the arm channel to avoid any arm complications.&#x2028; Materials and Methods: 3D-CT LG was performed on the day before the surgery to mark SN on the skin. Above the tumor and near the areola, 2 ml of Iopamidol was injected subcutaneously. A 16-channel multidetector-row helical CT images were taken at 1 min after injection for SN detection, and at 3 and 5 min for observing advancement of lymph flow into venous angle. They were reconstructed to produce a 3D image of lymph ducts and lymph nodes by shaded volume rendering method. SN biopsy and axillary node sampling were performed by dye-stain method using endoscopy.&#x2028; Results: We performed SN biopsy with 3D-CT LG in 146 patients. 3D-CT LG showed periareolar circular lymph ducts and complicated radial breast subcutaneous lymph ducts flow. They were connected to make a network. It clearly showed the precise lymphatic flow from the tumor to SN. 3D-CT lymphography can show sentinel lymph node at only one minute after injection. But following up to 3 minutes and 5 minutes after injection, we can follow the lymph ducts beyond SN into the second and the third nodes toward the venous angle with complex plexus. It shows five beads-like grouped nodes beyond SN. Detection rate was 100% for SN; 80.1% for the third group; and 30.1% for the fifth group. The position of SN and the other groups of axillary nodes were identified by their surrounding anatomical architecture of pectoral muscles and vascular systems, such as axillary vein, lateral thoracic artery, and thoracodorsal artery. Under the endoscopic technique, we can observe the dye-stained nodes in 63.3% of the second group and in 47.9% of the third group detected by 3D-CT LG. SN metastasis was positive in 40 patients, and only SN metastasis was found in 21 patients (52.5%) among them. Any skip metastasis beyond second and third nodes was not observed. Under the direct view, we can distinguish and the axillary node drained from the breast, guided by 3D-CT LG and dye-stain, in 40 patients with SN metastasis, and sample them selectively.&#x2028; Conclusions: By 3D-CT LG, we can recognize the accurate and more precise lymph flow, and their positional relations to surrounding anatomical architecture. It helps us easily to pursuit lymph flow and to remove SN and the axillary nodes from the breast selectively.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1012.

The survival pathways phosphatidylinositol-3 kinase (PI3-K)/phosphoinositide-dependent protein kinase 1 (PDK1)/Akt modulate liver regeneration through hepatocyte size rather than proliferation

Liver regeneration comprises a series of complicated processes. The current study was designed to investigate the roles of phosphoinositide-dependent protein kinase 1 (PDK1)-associated pathways in liver regeneration after partial hepatectomy (PH) using liver-specific Pdk1-knockout (L-Pdk1KO) and Pdk1/STAT3 double KO (L-DKO) mice. There was no liver regeneration, and 70% PH was lethal in L-Pdk1KO mice. Liver regeneration was severely impaired equally in L-Pdk1KO and L-DKO mice, even after nonlethal 30% PH. There was no cell growth (measured as increase of cell size) after hepatectomy in L-Pdk1KO mice, although the post-PH mitotic response was the same as in controls. As expected, hepatectomy did not induce hepatic Akt-phosphorylation (Thr308) in L-Pdk1KO mice, and post-PH phosphorylation of Akt, mammalian target of rapamycin (mTOR), p70 ribosomal S6 kinase (p70(S6K)), and S6 were also reduced. To examine the specific role of PDK1-associated signals, a "pif-pocket" mutant of PDK1, which allows PDK1 only to phosphorylate Akt, was used. Liver regeneration was recovered in L-Pdk1KO mice with a "pif-pocket" mutant of PDK1. This re-activated Akt in L-Pdk1KO mice liver and induced post-PH cell growth, without affecting cell proliferation. Further deletion of STAT3 (L-DKO mice) did not further deteriorate liver regeneration, although this certainly reduced post-PH mitotic response. These findings indicate that PDK1/Akt contribute to liver regeneration by regulating cell size. Regarding phosphatidylinositol-3 kinase (PI3-K), immediate upstream signal of PDK1, activation of PI3-K induced cell proliferation via STAT3 activation in the liver of L-Pdk1KO mice but did not improve impaired liver regeneration. This confirmed the pivotal role of PDK1 in liver regeneration and cell growth.

CONCLUSION

PDK1/Akt-mediated responsive cell growth is essential for normal liver regeneration after PH, especially when cell proliferation is impaired.