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Circadian disturbance of clock gene expression is a risk factor for diseases such as obesity, cancer, and sleep disorders. To study these diseases, it is necessary to monitor and analyze the expression rhythm of clock genes in the whole body for a long duration. The bioluminescent reporter enzyme firefly luciferase and its substrate d-luciferin have been used to generate optical signals from tissues in vivo with high sensitivity. However, little information is known about the stability of d-luciferin to detect gene expression in living animals for a long duration. In the present study, we examined the stability of a luciferin solution over 21 days. l-Luciferin, which is synthesized using racemization of d-luciferin, was at high concentrations after 21 days. In addition, we showed that bioluminescence of Period1 (Per1) expression in the liver was significantly decreased compared with the day 1 solution, although locomotor activity rhythm was not affected. These results showed that d-luciferin should be applied to the mouse within, at most, 7 days to detect bioluminescence of Per1 gene expression rhythm in vivo.

Because the disruption of circadian clock gene is a risk factor in many diseases such as obesity and cancer, it is important to monitor and analyzed the expression of the rhythm of the clock gene throughout the body over a long period of time. Although we previously reported on a new gene expression analysis system tracking a target position on the body surface of freely moving mice, the experimental apparatus required a large space. We have therefore developed an in vivo recording system using a portable photomultiplier tube (PMT) system attached to an optical fibre. Directly connecting the target area with the device, we could easily measure the photon counts in a very small space. However, little information is known about the characteristics of optical fibres when exposed to twisting/looping in association with a moving mouse and the effect of the surface of optical fibre. In the present study, we report on the characteristics of optical fibres to detect gene expression rhythm in freely moving mice. Using this portable optical device directly connected with a target area, we were able to measure the circadian rhythm of clock gene expression over a prolonged period in freely moving mice in a small space.

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.

In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography-tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030-0.973] and 0.003 ± 0.002 [0.001-0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol.

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.

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.

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.

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 and cancer. To understand the mechanism of regulating clock gene expression rhythms in vivo, multiple real time recording systems are required. In the present study, we developed a double recording system of Period1 expression rhythm in peripheral tissue (liver) and the brain. In peripheral tissue, quantification of gene expression in a steadily moving target was achieved by using a photomultiplier tube (PMT) attached to a tissue contact optical sensor (TCS). Using this technique, we were able to analyze circadian rhythms of clock gene expression over a prolonged period in the liver and olfactory bub (OB) of the brain. The present double recording system has no effect on behavioral activity or rhythm. Our novel system thus successfully quantifies clock gene expression in deep areas of the body in freely moving mice for a period sufficient to analyze circadian dynamics. In addition, our double recording system can be widely applied to many areas of biomedical research, as well as applications beyond medicine.

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-/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.

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 helixloophelix (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-3, 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.

Liver regeneration is an important and necessary process that the liver depends on for recovery from injury. The regeneration process consists of a complex network of cells and organs, including liver cells (parenchymal and non-parenchymal cells) and extrahepatic organs (thyroid, adrenal glands, pancreas, duodenum, spleen, and autonomic nervous system). The regeneration process of a normal, healthy liver depends mainly on hepatocyte proliferation, growth, and programmed cell death. Cell proliferation and growth are regulated in a cooperative manner by interleukin (IL)-6/janus kinase (Jak)/signal transducers and activators of transcription-3 (STAT3), and phosphoinositide 3-kinase (PI3-K)/phosphoinositide-dependent protein kinase 1 (PDK1)/Akt pathways. The IL-6/Jak/STAT3 pathway regulates hepatocyte proliferation and protects against cell death and oxidative stress. The PI3-K/PDK1/Akt pathway is primarily responsible for the regulation of cell size, sending mitotic signals in addition to pro-survival, antiapoptotic and antioxidative signals. Though programmed cell death may interfere with liver regeneration in a pathological situation, it seems to play an important role during the termination phase, even in a normal, healthy liver regeneration. However, further study is needed to fully elucidate the mechanisms regulating the processes of liver regeneration with regard to cell-to-cell and organ-to-organ networks at the molecular and cellular levels.

Bilberry has been reported to have anti-oxidant and anti-inflammatory properties. We studied the effect of bilberry (

Liver X Receptor (LXR)-agonist did not affect serum levels of glucose (GLU) and triglyceride (TG) after PH in db/db mice with fatty liver. Serum levels of glucose and TG were not affected post-PH 24 and 72Â h by the pre-treatment of GW4064 in db/db mice with fatty liver (5Â mg/kg BW, refer to Materials and Methods in details). (PPTX 74 kb)

The nuclear translocation of Nrf2 by GW4064 (0, 0.5, 1.0 and 2.0Â ÎźM) was studied immunocytochemically in AML12 mouse liver cells. (PPTX 2650 kb)

Objective and design: To examine the effect of 3-[(dodecylthiocarbonyl)-methyl]-glutarimide (DTCM-G), a novel anti-inflammatory agent that inhibits lipopolysaccharide (LPS) activation of RAW264.7 macrophages, on murine models of colitis and RAW264.7 cells. Materials and methods: Colitis was induced by rectally infusing trinitrobenzenesulfonic acid (TNBS) (1.5 mg in 50 % ethanol) in BALB/c mice or orally administering 3 % dextran sulfate sodium (DSS) for 5 days in C57BL/6 mice. The severity of colitis was assessed after intraperitoneally injecting DTCM-G (40 mg/kg). The anti-inflammatory properties of DTCM-G and its mechanisms were investigated in LPS-stimulated RAW264.7 cells. Results: DTCM-G significantly ameliorated TNBS-induced colitis, according to the body weight loss, disease activity index, colonic obstruction, macroscopic colonic inflammation score, mucosal myeloperoxidase activity, and histopathology. Immunohistochemistry and isolated lamina propria mononuclear cells showed significantly reduced colonic F4/80+ and CD11b+ macrophage infiltration. DTCM-G significantly suppressed tumor necrosis factor (TNF)-α and interleukin (IL)-6 messenger RNA expression in the colon and attenuated DSS-induced colitis, according to the disease activity index and histopathology. In RAW264.7 cells, DTCM-G suppressed LPS-induced TNF-α/IL-6 production and enhanced glycogen synthase kinase-3β phosphorylation. Conclusions: DTCM-G attenuated murine experimental colitis by inhibiting macrophage infiltration and inflammatory cytokine expression. Thus, DTCM-G may be a promising treatment for inflammatory bowel disease.

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. (Hepatology 2015;61:1343–1356)

We propose a new concept of tumor progression monitoring using dual luciferases in living animals to reduce stress for small animals and the cost of luciferin. The secreted Cypridina luciferase (CLuc) was used as an ex vivo indicator to continuously monitor tumor progression. On the other hand, the non-secreted firefly luciferase was used as an in vivo indicator to analyze the spatial distribution of the tumor at suitable time points indicated by CLuc. Thus, the new monitoring systems that use dual luciferases are available, allowing long-term bioluminescence imaging under minimal stress for the experimental animals.

Type XVII collagen (COL17) is a transmembrane protein located at the epidermal basement membrane zone. COL17 deficiency results in premature hair aging phenotypes and in junctional epidermolysis bullosa. Here, we show that COL17 plays a central role in regulating interfollicular epidermis (IFE) proliferation. Loss of COL17 leads to transient IFE hypertrophy in neonatal mice owing to aberrant Wnt signaling. The replenishment of COL17 in the neonatal epidermis of COL17-null mice reverses the proliferative IFE phenotype and the altered Wnt signaling. Physical aging abolishes membranous COL17 in IFE basal cells because of inactive atypical protein kinase C signaling and also induces epidermal hyperproliferation. The overexpression of human COL17 in aged mouse epidermis suppresses IFE hypertrophy. These findings demonstrate that COL17 governs IFE proliferation of neonatal and aged skin in distinct ways. Our study indicates that COL17 could be an important target of anti-aging strategies in the skin. DOI: http://dx.doi.org/10.7554/eLife.26635.001, eLife digest The skin is one of the largest organs of the body and is constantly confronted with a range of external stresses including germs, heat and scratches. The outermost part of the skin is called the epidermis and it acts as a barrier to the external environment and works to stop the body from losing water. An abnormally thin or thick epidermis can impair the skin’s ability to perform these roles. As such, the ability of epidermal cells to proliferate (i.e. divide to make new cells) is tightly regulated, both when the animal first develops and when it ages. However, most of the underlying mechanisms that regulate these processes are unknown. Watanabe et al. have now identified type XVII collagen (called COL17 for short) as a key molecule that controls how often epidermal cells in skin from mice and humans divide. COL17 is a protein that is made in the deepest layer of the epidermis, and it prevents the epidermis from thickening in newborn mice by coordinating with the Wnt signaling pathway. This signaling pathway, amongst other things, controls how often some cells divide. Older mice have a thicker epidermis than their younger counterparts. Watanabe et al. revealed that the distribution of COL17 in the epidermis also changes dramatically with age in mice and humans. Further experiments with mice showed that introducing COL17 back into the epidermis helped the tissue retain a more youthful state even in animals that had reached an old age. Together these findings give scientists a better understanding of how the ability of epidermal cells to divide is regulated at various stages in a mammal’s life. The new findings also point to COL17 as a promising component in future anti-aging strategies targeted at the skin. Yet first, further work will be needed to uncover how the production of COL17 is controlled in the epidermis. DOI: http://dx.doi.org/10.7554/eLife.26635.002

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.

Background Pancreatic islet transplantation (PITx) is an attractive treatment option for restoring appropriate glucose homeostasis in type 1 diabetes patients. Although islet grafts can successfully engraft after PITx, large numbers of islet grafts are required mainly because immune reactions, including inflammation, destroy islet grafts. In these processes, nuclear factor (NF)-κB plays a central role. We hypothesized that the inhibition of NF-κB activation would ameliorate inflammatory responses after PITx and aid successful engraftment. Methods To test this hypothesis, a newly developed NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), was used on a syngeneic mouse PITx model. One hundred seventy-five islets from C57BL/6 (B6) mice were transplanted into streptozotocin-induced diabetic B6 mice. The recipient mice were administered DHMEQ for 1, 2, or 3 days after PITx. The underlying mechanisms of DHMEQ on islet graft protection were investigated in an in vitro coculture model of pancreatic islets and macrophages. Results With a vehicle treatment, only 11.1% of the islet-recipients achieved normoglycemia after PITx. In sharp contrast, DHMEQ treatment markedly improved the normoglycemic rate, which was associated with the suppression of serum high mobility group complex-1 (HMGB1) and proinflammatory cytokines, including tumor necrosis factor-α, monocyte chemoattractant protein-1, macrophage inflammatory protein-1β, interleukin-1β, and interleukin-6, after PITx. In a murine macrophage-like cell line, DHMEQ inhibited HMGB1-driven activation and proinflammatory cytokine secretion and further prevented death isolated islets after coculture with these activated macrophages. Conclusions Inhibition of NF-κB activation by DHMEQ after PITx reduces the HMGB1-triggered proinflammatory responses and results in engraftment of transplanted islets even with fewer islet grafts.

Regulation of an intracellular acidic environment plays a pivotal role in biological processes and functions. However, spatiotemporal analysis of the acidification in complex tissues of living subjects persists as an important challenge. We developed a photo-inactivatable bioluminescent indicator, based on a combination of luciferase-fragment complementation and a photoreaction of a light, oxygen, and voltage domain from Avena sativa Phototropin1 (LOV2), to visualize temporally dynamic acidification in living tissue samples. Bioluminescence of the indicator diminished upon light irradiation and it recovered gradually in the dark state thereafter. The recovery rate was remarkably sensitive to pH changes but unsusceptible to fluctuation of luciferin or ATP concentrations. Bioluminescence imaging, taken as an index of the recovery rates, enabled long-time recording of acidification in apoptotic and autophagous processes in a cell population and an ischemic condition in living mice. This technology using the indicator is widely applicable to sense organelle-specific acidic changes in target biological tissues.

In-transit metastasis (ITM) is a unique manifestation of intralymphatic tumor dissemination, characterized by the presence of melanoma cells between the primary lesion and the draining regional lymph node basin that is clinically associated with poor prognosis. In this study, we aimed to establish an experimental animal model of melanoma ITM, as research progress in this field has been hampered by a lack of suitable experimental models. We reproduced melanoma ITM in a mouse hind limb by transplanting melanoma cells into the footpad of a mouse with lymphedema (LE). The tumor cells at the ITM site were highly proliferative, and mice with ITMs were more likely than control mice to develop distant lymph node and lung metastases. Peritumoral lymphatic vessels and tumor-associated blood vessels were increased in the primary tumor site of the LE mice. Our established ITM melanoma mouse model enabled us to clarify the molecular determinants and pathophysiology of ITM. This ITM model is also comparable to the unfavorable clinical behavior of melanoma ITM in humans and, moreover, underlined the importance of lymphangiogenic factors in the tumor dissemination through the lymphatic system.

Background Pharmacologically modulated dendritic cells (DCs) can potentially regulate alloimmune responses. We examined the characteristics of immunoregulatory DCs induced by a novel triazolopyrimidine derivative, NK026680, which has been previously shown to inhibit DC maturation. Methods DCs were generated from bone marrow progenitor cells from C57BL/6 (B6, H-2 haplotype) mice with granulocyte-macrophage colony-stimulating factor and interleukin (IL)-4. DCs were cultured with allogeneic BALB/c (H-2) splenocyte lysates with or without NK026680. DC functions were examined in vitro after stimulation of tumor necrosis factor α and in vivo by the intravenous injection of C3He/J (C3H, H-2) DCs cultured with B6 cell lysates and NK026680 into C3H mice. Seven days later, DC-treated mice received B6 heart allografts, and graft survival and alloimmune responses were assessed. Results In NK026680-treated DCs (NK-DCs), significant inhibition of the up-regulation of surface activation markers (CD40, CD80, CD86, and major histocompatibility complex class II) and IL-12 p40 production was observed after stimulation of tumor necrosis factor α compared with that of control DCs. Furthermore, NK-DCs suppressed alloreactive T-cell proliferation. The modulation of NK-DCs was likely associated with the inhibition of phosphorylation of p38 mitogen-activated protein kinase and the up-regulation of indolamine 2,3-dioxygenase expression. Compared with both noninjected and control DC-injected mice, mice that received a single in vivo infusion of NK-DCs showed significant increases in splenocyte IL-10 production and the splenic CD4 IL-10 T-cell population 7 days after injection, a significantly increased splenic CD4CD25FoxP3 T-cell population 14 days after injection, and markedly prolonged cardiac allograft survival. Conclusions Ex vivo NK026680 conditioning allows DCs to acquire immunoregulatory properties that suppress alloimmune responses and prolong cardiac allograft survival.

Summary 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 Ca2+ -dependent proteases activity were assessed in the 24-h preservation group. The cytosolic Ca2+ 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 Ca2+ overload during cold preservation. Dsol inhibited myocardial injury and improved graft survival by suppressing Ca2+ overload during the preservation and the activation of Ca2+ -dependent proteases. Dsol is therefore considered a better alternative to UW to ameliorate the outcome of heart transplantation.

We demonstrate a novel rapid direct detection method for immunohistochemistry, using a bioluminescent probe. An anti-CEA antibody-fused far-red bioluminescent protein can monitor the accumulation of this type of probe in tumour tissues. The bimodal spectrum (λmax = 460 and 675 nm) of this bioluminescent probe is extremely stable under different conditions of pH and ion concentration. The sensitivity of our bioluminescent labelling was at the same level of enzymatic labelling, e.g. peroxidase, as an indirect system. Our novel technique is simple and can shorten the pretreatment time of paraffin sections to around 30 min. The utility of our bioluminescent labelling covers all imaging in vitro, in vivo and ex vivo, suggesting that our antibody-fused bioluminescent probe has the potential to detect tumour antigens with a high sensitivity in routine immune histological examinations. Copyright © 2012 John Wiley & Sons, Ltd.

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.

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.

We have previously synthesized a novel piperidine compound, 3-[(dodecylthiocarbonyl)methyl]glutarimide (DTCM-glutarimide), that inhibits LPS-induced NO production, and in the present research we studied further the anti-inflammatory activity of DTCM-glutarimide in a macrophage cell line and in mice bearing transplanted hearts. Mouse macrophage-like RAW264.7 cells were employed for the evaluation of cellular inflammatory activity. DTCM-glutarimide was synthesized in our laboratory. The AP-1 activity was measured by nuclear translocation and phosphorylation. For the heart transplantation experiment, male C57BL/6 (H-2b) and BALB/c (H-2d) mice were used as donor and recipient, respectively. DTCM-glutarimide was administered intraperitoneally. DTCM-glutarimide inhibited the LPS-induced expression of iNOS and COX-2 in macrophages; but, unexpectedly, it did not inhibit LPS-induced NF-κB activation. Instead, it inhibited the nuclear translocation of both c-Jun and c-Fos. It also inhibited LPS-induced c-Jun phosphorylation. Moreover, it inhibited the mixed lymphocyte reaction in primary cultures of mouse spleen cells; and furthermore, in mice it prolonged the graft survival in heart transplantation experiments. The novel piperidine compound, DTCM-glutarimide, was found to be a new inhibitor of macrophage activation, inhibiting AP-1 activity. It also inhibited graft rejection in mice, and thus may be a candidate for an anti-inflammatory agent.

Liver regeneration involves complicated processes and is affected by various patho-physiological conditions. This study was designed to examine the molecular mechanisms underlying the aging-associated impairment of liver regeneration. Male C57BL/6J mice were used as young and aged mice (10 weeks and20 months old, respectively). These mice were subjected to 70% partial hepatectomy (PH). Liver regeneration and liver injury/stresses were evaluated chronologically after PH. Post-hepatectomy liver regeneration was markedly impaired in aged mice. Though the extent of hepatocyte proliferation in the regenerating liver was similar in aged and young mice, cell growth was absent in aged mice. Oxidative stress (OS) was observed immediately after hepatectomy, followed by marked apoptosis in aged mice. Signaling molecules regarding cell proliferation (mitogen-activated protein kinase, STAT3, p46/52(Shc)) and anti-oxidation (catalase, superoxide dismutase, Ref-1, glutathione peroxidase) were expressed/activated after hepatectomy in livers of both aged and young mice. Akt was not activated in aged-mouse liver, but its expression was similar to that in young mice. p66(Shc), known as an age-/oxidant-associated protein, was strongly phosphorylated. By knocking down p66(Shc), the impairment of liver regeneration was normalized. OS immediately after hepatectomy induced subsequent liver injury (apoptosis), and deletion of p66(Shc) suppressed both OS and hepatocyte apoptosis in the regenerating liver of aged mice. Though we need additional data in other animal models to fully understand the mechanism, p66(Shc) may have a pivotal function in the impairment of liver regeneration in aged mice by triggering OS and subsequent apoptosis. This data may provide a clue to understanding the mechanism underlying the association between aging and the impairment of liver regeneration.

Unlike the case with some other solid tumors, whole genome array screening has not revealed prognostic genetic aberrations in primary gastric cancer. Comparative genomic hybridization (CGH) using bacterial artificial chromosome (BAC) arrays for 56 primary gastric cancers resulted in identification of four prognostic loci in this study: 6q21 (harboring FOXO3A; previously FKHRL1), 9q32 (UGCG), 17q21.1 approximately q21.2 (CASC3), and 17q21.32 (HOXB3 through HOXB9). If any one of these four loci was deleted, the prognosis of the patient was significantly worse (P = 0.0019). This was true even for advanced tumors (stage IIIA, IIB, or IV, n = 39) (P = 0.0113), whereas only 1 of the 17 patients with less advanced tumors (stage IA, IB, or II; n = 17) died of disease after surgery. Multivariate analysis according to the status of four BACs or pathological stage based on the Japanese Classification of Gastric Carcinoma (stages IA, IB, and II vs. stages IIIA, IIIB, and IV) demonstrated that the BAC clone status was also an independent prognostic factor (P = 0.006). These findings may help predict which patients with malignant potential need more intensive therapy, or may point to new therapeutic approaches especially for advanced tumors. The parameter here termed the integrated genomic prognostic biomarker may therefore be of clinical utility as a prognostic biomarker.

Liver regeneration is a necessary process that most liver damage depends on for recovery. Regeneration is achieved by a complex interactive network consisting of liver cells (hepatocytes, Kupffer cells, sinusoidal endothelial cells, hepatic stellate cells, and stem cells) and extrahepatic organs (thyroid gland, adrenal gland, pancreas, duodenum, and autonomous nervous system). The restoration of liver volume depends on hepatocyte proliferation, which includes initiation, proliferation, and termination phases. Hepatocytes are "primed" mainly by Kupffer cells via cytokines (IL-6 and TNF-alpha) and then "proliferation" and "cell growth" of hepatocytes are induced by the stimulations of cytokines and growth factors (HGF and TGF-alpha). Liver regeneration is achieved by cell proliferation and cell growth, where the IL-6/STAT3 and PI3-K/PDK1/Akt pathways play pivotal roles, respectively. IL-6/STAT3 pathway regulates hepatocyte proliferation via cyclin D1/p21 and protects against cell death by upregulating FLIP, Bcl-2, Bcl-xL, Ref1, and MnSOD. PI3-K/PDK1/Akt is known to be responsible for regulation of cell size via its downstream molecules such as mTOR in addition to being known for its survival, anti-apoptotic and anti-oxidative properties. Although the molecular mechanisms of liver regeneration have been actively studied, the mechanisms of liver regeneration must be elucidated and leveraged for the sufficient treatment of liver diseases.

Please cite this paper as: Signal transducer and activator of transcription 3 upregulates interleukin-8 expression at the level of transcription in human melanoma cells. Experimental Dermatology 2010; 19: e50–e55. Abstract: Many melanoma cells continuously produce interleukin-8 (IL-8). The involvement of signal transducer and activator of transcription 3 (STAT3) in the constant production of IL-8 in melanoma cells was examined. The level of IL-8 production correlated well with that of the phosphorylated (activated) STAT3 in six human melanoma cell lines. Introduction of the constitutively activated form of STAT3 (STAT3-C) into WM35 melanoma cells, that show low levels of IL-8 and phosphorylated STAT3, enhanced IL-8 production. Knockdown of STAT3 suppressed IL-8 production in WM1205Lu cells that contain a high level of IL-8 accompanied by STAT3 phosphorylation. Introduction of STAT3-C markedly increased the luciferase activity in WM1205Lu cells transfected with reporter vectors linked to the 5′-flanking region of the IL-8 gene from -546 to +44 base pair (bp) and from -272 to +44 bp, but not in cells expressing reporter plasmids from -133 to +44 bp and from -98 to +44 bp. These results indicate that the upregulation of IL-8 production is caused by constitutive STAT3 activation at the level of gene transcription in melanoma cells.

Background/Aims The autonomic vagus nerve is thought to play an essential role in liver regeneration since hepatic vagotomy delays hepatic DNA synthesis. However, how the parasympathetic vagus nerve is involved in liver regeneration remains obscure. Kupffer cells are located in liver sinusoids adjacent to hepatocytes and might regulate liver regeneration by releasing interleukin-6 (IL-6). The present study examines the role of the vagus nerve and how Kupffer cells are involved in parasympathetic nerve-mediated liver regeneration in mice. Methods We performed surgical vagotomy of the hepatic branch and then partial hepatectomy (PH); some mice received acetylcholine (ACh) agonist/antagonist before PH. We then evaluated liver regeneration and signal transducer and activator of transcription-3 (STAT3) activation. We also investigated whether ACh stimulates IL-6 release from Kupffer cells. Results Surgical vagotomy impaired liver regeneration. STAT3, which is activated by IL-6 after hepatectomy and plays a pivotal role in liver regeneration, was less activated in vagotomized mice after PH. Post-PH STAT3 activation was recovered by administering vagotomized mice with an ACh agonist. Furthermore, ACh stimulated IL-6 release in Kupffer cells in vitro. Conclusion The parasympathetic system (vagus nerve) contributes to liver regeneration after hepatectomy by stimulating IL-6 release from Kupffer cells followed by STAT3 activation in hepatocytes.

The interaction between interleukin-10 (IL-10) and interleukin-6 (IL-6) was investigated in the inflammatory response to Rhodococcus aurantiacus (R. aurantiacus) infection, in which both cytokines act as anti-inflammatory cytokines. Compared with wild-type (WT) counterparts, IL-6 gene-deficient (IL-6(-)/(-)) mice mounted a more robust production of IL-10 and tumor necrosis factor-alpha (TNF-alpha) during the initial phase of infection. Administration of anti-IL-10 antibody resulted in all the mice dying within 3 days post-infection as well as a further elevated TNF-alpha release. In vitro challenge of the macrophages from IL-6(-)/(-) and WT mice with heat-killed R. aurantiacus also showed similar results. Addition of exogenous IL-6 depressed IL-10 and TNF-alpha production by either IL-6(-)/(-) mice or IL-6(-)/(-) mouse macrophages. Likewise, WT mouse macrophages pretreated with anti-IL-10 or anti-IL-6 antibody exhibited increased production of TNF-alpha and IL-6 or IL-10 respectively. Moreover, neutralization of both IL-10 and IL-6 induced a further increase in TNF-alpha production by WT mouse cells. Overall, we conclude that IL-10 is a key element in protecting mice against mortality, and that IL-10 and IL-6 production are negatively regulated by each other although they are additive in suppressing TNF-alpha release in R. aurantiacus-infected mouse model.

Background Nuclear factor-κB regulates the expression of several genes involved in inflammation, the immune response, apoptosis, cell survival, and proliferation. Many of these same genes are activated during ischemia/reperfusion (I/R) injury. Here, we examined the anti-inflammatory efficacy of a newly developed nuclear factor-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), in the intestinal I/R injury model of rats. Materials and methods Intestinal ischemia was induced by occluding the superior mesenteric artery for 60 min. The experimental animals were divided into two groups: untreated group, control; treated group, DHMEQ-treated (20 mg/kg). DHMEQ were administered intraperitoneally at 60 min prior to clamping and 5 min prior to reperfusion. Animal survival rates, intestinal tissue blood flow, serum levels of tumor necrosis factor-alpha, and interleukin-6, and the histopathology of both the intestine and the lung were analyzed. Results The DHMEQ-treated animals exhibited higher values of intestinal tissue blood flow and suppression of tumor necrosis factor-alpha and interleukin-6 production, resulting in marked prolongation of their survival times. Histopathological findings obtained by examining tissues from control animals revealed severe intestinal mucosal damage and disruption of the lung alveolar architecture accompanied by hemorrhage and marked neutrophilic infiltration. These findings were significantly ameliorated in DHMEQ-treated animals. Conclusion DHMEQ effectively prevented both intestine and lung injuries in rat intestinal I/R models. This agent may possess a good potency for clinical application in various pathological settings including intestinal I/R and/or inflammatory acute lung injury.

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 (p70S6K), 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. (HEPATOLOGY 2009;49:204-214.)

We have developed a simple and reliable method for determining plasma concentration of dehydroxymethylepoxyquinomicin (DHMEQ), a new low molecular weight NF-κB inhibitor, using high performance liquid chromatography with mass spectrometry (LC–MS). An experiment of mass spectrometry with electrospray ionization in the negative ionization mode was performed to detect ion transitions at m / z 260.05 [M−H] − for DHMEQ and 240.29 for mefenamic acid as an internal standard. The samples were purified using liquid–liquid extraction with ethyl acetate. The method yielded a standard curve which was linear for the concentration range of 0.1–125 ng/mL when 0.05 mL plasma was used. The correlation coefficients of all standard curves were greater than or equal to 0.999. The limit of detection was 50 pg/mL (signal/noise >3). Daily fluctuation of plasma standard curve was small. The intra- and inter-assay precision ranged from 2.84 to 4.76% ( n = 6) and 2.91 to 7.03% ( n = 6), respectively. The LC–MS technique described provides a simple and reliable liquid chromatographic method for the determination of DHMEQ level and for use in studies involving pharmacokinetics.