L-type amino acid transporter 1 in hypothalamic neurons in mice maintains energy and bone homeostasis

Hypothalamic neurons regulate body homeostasis by sensing and integrating changes in the levels of key hormones and primary nutrients (amino acids, glucose, and lipids). However, the molecular mechanisms that enable hypothalamic neurons to detect primary nutrients remain elusive. Here, we identified L-type amino acid transporter 1 (LAT1) in hypothalamic leptin receptor (LepR)-expressing neurons as being important for systemic energy and bone homeostasis. We observed LAT1-dependent amino acid uptake in the hypothalamus, which was compromised in a mouse model of obesity and diabetes. Mice lacking LAT1 (encoded by Slc7a5) in LepR-expressing neurons exhibited obesity-related phenotypes and higher bone mass. Slc7a5 deficiency caused sympathetic dysfunction and leptin insensitivity in LepR-expressing neurons before obesity onset. Importantly, restoring Slc7a5 expression selectively in LepR-expressing ventromedial hypothalamus neurons rescued energy and bone homeostasis in mice deficient for Slc7a5 in LepR-expressing cells. Mechanistic target of rapamycin complex-1 (mTORC1) was found to be a crucial mediator of LAT1-dependent regulation of energy and bone homeostasis. These results suggest that the LAT1-mTORC1 axis in LepR-expressing neurons controls energy and bone homeostasis by fine-tuning sympathetic outflow, thus providing in vivo evidence of the implications of amino acid sensing by hypothalamic neurons in body homeostasis.

Amelioration of Osteoarthritis Development by Daily Oral Supplementation of Royal Jelly

Royal jelly (RJ), an essential food for the queen honeybee, has a variety of biological activities. Although RJ exerts preventive effects on various lifestyle-related diseases, such as osteoporosis and obesity, no study evaluated the effect of RJ on the development of osteoarthritis (OA), the most common degenerative joint disease. Here, we showed that daily oral administration of raw RJ significantly prevented OA development in vivo following surgically-induced knee joint instability in mice. Furthermore, in vitro experiments using chondrocytes, revealed that raw RJ significantly reduced the expression of inflammatory cytokines and enzymes critical for the degradation of the extracellular matrix (ECM). Similar results were observed after treatment with 10-hydroxy-2-decenoic acid, the most abundant and unique fatty acid in raw RJ. Our results suggest that oral supplementation with RJ would benefit the maintenance of joint health and prophylaxis against OA, possibly by suppressing the activity of inflammatory cytokines and ECM-degrading enzymes.

MEK5-ERK5 axis promotes self-renewal and tumorigenicity of glioma stem cells

Glioma stem cells (GSCs) promote the malignancy of glioblastoma (GBM), the most lethal brain tumor. Extracellular signal-regulated kinase 5 (ERK5) belongs to the mitogen-activated protein kinase (MAPK) family. Here, we demonstrated that mitogen-activated protein kinase kinase 5 (MEK5)-ERK5-signal transducer and activator of transcription 3 (STAT3) pathway plays an essential role in maintaining GSC stemness and tumorigenicity by integrating genetic and pharmacological manipulation and RNA sequencing (RNA-seq) analysis of clinical specimens. ERK5 was highly expressed and activated in GSCs. ERK5 silencing by shRNA in GSCs suppressed the self-renewal potential and GBM malignant growth concomitant with downregulation of STAT3 phosphorylation. Conversely, the activation of the MEK5-ERK5 pathway by introducing ERK5 or MEK5 resulted in increased GSC stemness. The introduction of STAT3 counteracted the GSC phenotypes by ERK5 silencing. Moreover, ERK5 expression and signaling are associated with poor prognosis in GBM patients with high stem cell properties. Finally, pharmacological inhibition of ERK5 significantly inhibited GSC self-renewal and GBM growth. Collectively, these findings uncover a crucial role of the MEK5-ERK5-STAT3 pathway in maintaining GSC phenotypes and GBM malignant growth, thereby providing a potential target for GSC-directed therapy.

Conditional inactivation of the L-type amino acid transporter LAT1 in chondrocytes models idiopathic scoliosis in mice

Scoliosis, usually diagnosed in childhood and early adolescence, is an abnormal lateral curvature of the spine. L-type amino acid transporter 1 (LAT1), encoded by solute carrier transporter 7a5 (Slc7a5), plays a crucial role in amino acid sensing and signaling in specific cell types. We previously demonstrated the pivotal role of LAT1 on bone homeostasis in mice, and the expression of LAT1/SLC7A5 in vertebral cartilage of pediatric scoliosis patients; however, its role in chondrocytes on spinal homeostasis and implications regarding the underlying mechanisms during the onset and progression of scoliosis, remain unknown. Here, we identified LAT1 in mouse chondrocytes as an important regulator of postnatal spinal homeostasis. Conditional inactivation of LAT1 in chondrocytes resulted in a postnatal-onset severe thoracic scoliosis at the early adolescent stage with normal embryonic spinal development. Histological analyses revealed that Slc7a5 deletion in chondrocytes led to general disorganization of chondrocytes in the vertebral growth plate, along with an increase in apoptosis and a decrease in cell proliferation. Furthermore, loss of Slc7a5 in chondrocytes activated the general amino acid control (GAAC) pathway but inactivated the mechanistic target of rapamycin complex 1 (mTORC1) pathway in the vertebrae. The spinal deformity in Slc7a5-deficient mice was corrected by genetic inactivation of the GAAC pathway, but not by genetic activation of the mTORC1 pathway. These findings suggest that the LAT1-GAAC pathway in chondrocytes plays a critical role in the maintenance of proper spinal homeostasis by modulating cell proliferation and survivability.

The role of CDK8 in mesenchymal stem cells in controlling osteoclastogenesis and bone homeostasis

Bone marrow mesenchymal stem cells (MSCs) are critical regulators of postnatal bone homeostasis. Osteoporosis is characterized by bone volume and strength deterioration, partly due to MSC dysfunction. Cyclin-dependent kinase 8 (CDK8) belongs to the transcription-related CDK family. Here, CDK8 in MSCs was identified as important for bone homeostasis. CDK8 level was increased in aged MSCs along with the association with aging-related signals. Mouse genetic studies revealed that CDK8 in MSCs plays a crucial role in bone resorption and homeostasis. Mechanistically, CDK8 in MSCs extrinsically controls osteoclastogenesis through the signal transducer and transcription 1 (STAT1)-receptor activator of the nuclear factor κ Β ligand (RANKL) axis. Moreover, aged MSCs have high osteoclastogenesis-supporting activity, partly through a CDK8-dependent manner. Finally, pharmacological inhibition of CDK8 effectively repressed MSC-dependent osteoclastogenesis and prevented ovariectomy-induced osteoclastic activation and bone loss. These findings highlight that the CDK8-STAT1-RANKL axis in MSCs could play a crucial role in bone resorption and homeostasis.

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Aging increases CDK8 expression level in MSCs and their progeny

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CDK8 in MSCs plays a crucial role in bone resorption and homeostasis

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CDK8 in MSCs extrinsically controls osteoclastogenesis through STAT1/RANKL axis

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CDK8 inhibitor prevents ovariectomy-induced osteoclastic activation and bone loss

SMURF2 phosphorylation at Thr249 modifies glioma stemness and tumorigenicity by regulating TGF-β receptor stability

Glioma stem cells (GSCs) contribute to the pathogenesis of glioblastoma, the most malignant form of glioma. The implication and underlying mechanisms of SMAD specific E3 ubiquitin protein ligase 2 (SMURF2) on the GSC phenotypes remain unknown. We previously demonstrated that SMURF2 phosphorylation at Thr²⁴⁹ (SMURF2^Thr249) activates its E3 ubiquitin ligase activity. Here, we demonstrate that SMURF2^Thr249 phosphorylation plays an essential role in maintaining GSC stemness and tumorigenicity. SMURF2 silencing augmented the self-renewal potential and tumorigenicity of patient-derived GSCs. The SMURF2^Thr249 phosphorylation level was low in human glioblastoma pathology specimens. Introduction of the SMURF2^T249A mutant resulted in increased stemness and tumorigenicity of GSCs, recapitulating the SMURF2 silencing. Moreover, the inactivation of SMURF2^Thr249 phosphorylation increases TGF-β receptor (TGFBR) protein stability. Indeed, TGFBR1 knockdown markedly counteracted the GSC phenotypes by SMURF2^T249A mutant. These findings highlight the importance of SMURF2^Thr249 phosphorylation in maintaining GSC phenotypes, thereby demonstrating a potential target for GSC-directed therapy.

Hiraiwa et al. show that phosphorylation of SMAD specific E3 ubiquitin protein ligase 2 (SMURF2) at Thr249 mediates ubiquitylation and degradation of the TGF-β receptor TGBR1 leading to loss of glioblastoma stem cell tumorigenic capacity. Their data elucidates a mechanism of regulation of the TGF-β signaling pathway that controls the stem cell status in glioblastoma.

CDK8 maintains stemness and tumorigenicity of glioma stem cells by regulating the c-MYC pathway

Glioblastoma (GBM) is the most malignant form of glioma. Glioma stem cells (GSCs) contribute to the initiation, progression, and recurrence of GBM as a result of their self-renewal potential and tumorigenicity. Cyclin-dependent kinase 8 (CDK8) belongs to the transcription-related CDK family. Although CDK8 has been shown to be implicated in the malignancy of several types of cancer, its functional role and mechanism in gliomagenesis remain largely unknown. Here, we demonstrate how CDK8 plays an essential role in maintaining stemness and tumorigenicity in GSCs. The genetic inhibition of CDK8 by shRNA or CRISPR interference resulted in an abrogation of the self-renewal potential and tumorigenicity of patient-derived GSCs, which could be significantly rescued by the ectopic expression of c-MYC, a stem cell transcription factor. Moreover, we demonstrated that the pharmacological inhibition of CDK8 significantly attenuated the self-renewal potential and tumorigenicity of GSCs. CDK8 expression was significantly higher in human GBM tissues than in normal brain tissues, and its expression was positively correlated with stem cell markers including c-MYC and SOX2 in human GBM specimens. Additionally, CDK8 expression is associated with poor survival in GBM patients. Collectively, these findings highlight the importance of the CDK8-c-MYC axis in maintaining stemness and tumorigenicity in GSCs; these findings also identify the CDK8-c-MYC axis as a potential target for GSC-directed therapy.

Daily oral supplementation of Hochu-Ekki-To prevents osteoclastic activation and bone loss in ovariectomized mice

Bone remodeling is sophisticatedly regulated by two different cell types: bone-resorbing osteoclasts and bone-forming osteoblasts. Hochu-Ekki-To, a Japanese traditional herbal medicine, is commonly used for the treatment of chronic diseases or frailty after an illness; however, its effects on metabolic bone diseases such as osteoporosis are not well known. We herein report that daily oral Hochu-Ekki-To administration significantly inhibits osteoclast activation as well as the reduction in bone volume in ovariectomized mice. Our results suggest that supplementation with Hochu-Ekki-To might be beneficial for the prophylaxis and treatment of metabolic bone diseases associated with abnormal osteoclast activation.

mTORC1 Overactivation Leads to Abnormalities in Skeletal Development

The mechanistic/mammalian target of rapamycin complex-1 (mTORC1) integrates multiple signaling pathways and regulates various cellular processes. Tuberous sclerosis complex 1 (Tsc1) and complex 2 (Tsc2) are critical negative regulators of mTORC1. Mouse genetic studies, including ours, have revealed that inactivation of mTORC1 in undifferentiated mesenchymal cells and chondrocytes leads to severe skeletal abnormalities, indicating a pivotal role for mTORC1 in skeletogenesis. Here, we show that hyperactivation of mTORC1 influences skeletal development through its expression in undifferentiated mesenchymal cells at the embryonic stage. Inactivation of Tsc1 in undifferentiated mesenchymal cells by paired-related homeobox 1 (Prx1)-Cre-mediated recombination led to skeletal abnormalities in appendicular skeletons. In contrast, Tsc1 deletion in chondrocytes using collagen type II α1 (Col2a1)-Cre or in osteoprogenitors using Osterix (Osx)-Cre did not result in skeletal defects in either appendicular or axial skeletons. These findings indicate that Tsc complex-mediated chronic overactivation of mTORC1 influences skeletal development at the embryonic stage through its expression in undifferentiated mesenchymal cells but not in chondrocytes or osteoprogenitors.

mTOR regulates skeletogenesis through canonical and noncanonical pathways

The mechanistic/mammalian target of rapamycin (mTOR) regulates various cellular processes, in part through incorporation into distinct protein complexes. The mTOR complex 1 (mTORC1) contains the Raptor subunit, while mTORC2 specifically contains the Rictor subunit. Mouse genetic studies, including ours, have revealed a critical role for mTOR in skeletogenesis through its expression in undifferentiated mesenchymal cells. In addition, we have recently revealed that mTORC1 expression in chondrocytes is crucial for skeletogenesis. Recent work indicates that mTOR regulates cellular functions, depending on the context, through both complex-dependent (canonical pathway) and complex-independent roles (noncanonical pathway). Here, we determined that mTOR regulates skeletal development through the noncanonical pathway, as well as the canonical pathway, in a cell-type and context-specific manner. Inactivation of Mtor in undifferentiated mesenchymal cells or chondrocytes led to either severe hypoplasia in appendicular skeletons or a severe and generalized chondrodysplasia, respectively. Moreover, Rictor deletion in undifferentiated mesenchymal cells or chondrocytes led to mineralization defects in some skeletal components. Finally, we revealed that simultaneous deletion of Raptor and Rictor in undifferentiated mesenchymal cells recapitulated the appendicular skeletal phenotypes of Mtor deficiency, whereas chondrocyte-specific Raptor and Rictor double-mutants exhibited milder hypoplasia of appendicular and axial skeletons than those seen upon Mtor deletion. These findings indicate that mTOR regulates skeletal development mainly through the canonical pathway in undifferentiated mesenchymal cells, but at least in part through the noncanonical pathway in chondrocytes.

An effective method to release human islets from surrounding acinar cells with agitation in high osmolality solution

INTRODUCTION

Islet purification is mainly performed by the density gradient method. However, purification of the embedded islets that are surrounded by exocrine tissue should be difficult, because their density is similar to exocrine tissue. In this study, we performed chart review to assess the relationship between the ratio of embedded islets and efficacy of purification. Then, we tested several conditions of a new method to free the islets from surrounded exocrine tissues using high osmolality solution with gentle agitation.

MATERIALS AND METHODS

First, we performed chart review of our human islet isolation. Second, embedded islet-enriched human islet fractions (embedded islets >50%) were suspended in University of Wisconsin (UW) solution (UW group, 320 mOsm/kg/H(2)0) or osmolality-adjusted UW solution (400, 500, and 600 mOsm/kg/H(2)0; 400 group, 500 group, and 600 group, respectively). Each tube was gently shaken at 4°C. The tissue samples were taken before shaking and after 15, 30, and 60 minutes. Islet yield, percentage of embedded islets, and viabilities were assessed.

RESULTS

The chart review revealed that high ratio of embedded islets deteriorated the efficacy of islet purification. The islet yield in all groups except for the 600 group did not change at 15 minutes, but it decreased in all groups at 60 minutes. The average percentage of embedded islets before shaking was 62.6%. Although percentage of embedded islets were decreasing in all groups, it was < 20% at 15 minutes in the 500 and 600 groups whereas it was >44% in the UW group, which indicated that higher osmolality would have a greater effect. Viability was >95% in all groups at 30 minutes.

CONCLUSIONS

The embedded islets deteriorated the efficacy of islet purification. Gentle agitation of embedded islets in high osmolality (500 mOsm/kg/H(2)O, 15 minutes) could release islets from surrounded exocrine tissue.

Usefulness of the secretory unit of islet transplant objects (SUITO) index for evaluation of clinical autologous islet transplantation

BACKGROUND

Assessing the engrafted islet mass is important in evaluating the efficacy of islet transplantation. We previously demonstrated that the average secretory unit of islet transplant objects (SUITO) index within 1 month of allogeneic islet transplantation was an excellent predictor of insulin independence. However, the usefulness of the SUITO index for evaluating autologous islet transplantation has not been explored. The purpose of the present study was to assess the relationship between the SUITO index and clinical outcomes after total pancreatectomy followed by autologous islet transplantation.

METHODS

We performed 27 total pancreatectomies followed by autologous islet transplantation from October 2006 to January 2011. Cases were divided into an insulin-independent group (IIG; n = 12) and an insulin-dependent group (lDG; n = 15). The SUITO index was calculated by the formula [fasting C-peptide (ng/mL)/fasting glucose (mg/dL) -63] × 1,500. The average SUITO index within the first month of transplantation except for days 0, 1, and 2, maximum SUITO index, and most recent SUITO index were calculated in each case, and values were compared between the IIG and the IDG.

RESULTS

The average SUITO index within 1 month was significantly higher in the IIG than in the IDG (24.6 ± 3.4 vs 14.9 ± 2.0, respectively; P < .02). The maximum SUITO indices were 45.7 ± 7.7 in the IIG and 30.1 ± 8.1 in the IDG (not significant), and the recent SUITO indices were 36.9 ± 6.7 in the IIG and 22.8 ± 6.1 in the IDG (not significant).

CONCLUSIONS

The average SUITO index within 1 month was an excellent predictor of insulin independence after total pancreatectomy followed by autologous islet transplantation.

Evidence for instant blood-mediated inflammatory reaction in clinical autologous islet transplantation

A nonspecific inflammatory and thrombotic reaction termed instant blood-mediated inflammatory reaction (IBMIR) has been reported when allogenic or xenogenic islets come into contact with blood. This reaction is known to cause significant loss of transplanted islets. We hypothesized that IBMIR occurs in patients undergoing total pancreatectomy followed by autologous islet transplantation (TP-AIT) and tested this hypothesis in 24 patients and in an in vitro model. Blood samples drawn during the peritransplant period showed a significant and rapid increase of thrombin-anti-thrombin III complex (TAT) and C-peptide during islet infusion, which persisted for up to 3 h, along with a decreased platelet count. A concomitant increase in levels of inflammatory proteins IL-6, IL-8 and interferon-inducible protein-10 was observed. An in vitro model composed of pure islets plus autologous blood also demonstrated significantly increased levels of TAT (p<0.05), C-peptide (p<0.05), tumor necrosis factor-alpha (p<0.05) and MCP-1 (p<0.05), as well as strong tissue factor expression in islets. Islet viability decreased significantly but was rescued by the presence of low-molecular-weight dextran sulfate. In conclusion, AIT-induced elevation of TAT and destruction of islets suggests that IBMIR might occur during AIT. Modulating this process may help improve islet engraftment and the insulin independence rate in TP-AIT patients.

The impact of bevacizumab on liver regeneration following hepatectomy in rats

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Background: In our clinical data, we had the interesting findings that the pathologic sinusoidal obstruction syndrome and serum hyaluronic acid after neoadjuvant oxaliplatin-associated chemotherapy for liver metastatic colorectal cancer with bevacitumab (Bev) was ameliorated compared to those without Bev. The purpose of this study was to investigate the influence of bevacizumab administration on regenerating liver in rat 70% and 90% hepatectomy (Hx) model as a surrogate model of human massive hepatectomy for liver metastatic colorectal cancer.

Methods: Male Wister rats weighing 180-230g were divided into the following four groups: 70%Hx, 70%Hx + Bev, 90%Hx and 90%Hx+Bev group. The rats were pretreated with intraperitoneal administration of bevacizumab (5mg/kg) 7 days before hepatectomy. The remnant liver and blood samples were taken one day after hepatectomy, and the following parameters were evaluated: blood analysis (AST, ALT, LDH, T- Bil, and hyaluronic acid), liver weight to body weight (Lw/Bw) ratio, and postoperative survival rate for three days.

Results: In the 70%Hx model, there was no significant difference between the 70%Hx group and 70%Hx + Bev group in blood analysis one day after hepatectomy; AST (1928 vs. 923 IU/L), ALT (1282 vs. 670 IU/L), T-Bil (0.17 vs. 0.19 mg/dl), LDH (3822 vs. 2967 U/L) and hyaluronic acid (995.7 vs. 1026.6 ng/ml) and in Lw/Bw ratio (1.78 vs. 1.84). In 90%Hx model, AST and ALT of blood analysis in 90%Hx+Bev group significantly decreased compared to those in 90%Hx group; AST (3428 vs. 4995 IU/L, P<0.05), ALT (1471 vs. 2287 IU/L, P<0.05), T-Bil (1.94 vs. 2.57 mg/dl), LDH (3229 vs. 5351 U/L) and hyaluronic acid (3865.7 vs. 7862.2 ng/ml). The Lw/Bw ratio in 90%Hx+Bev group significantly increased compared to that in 90%Hx group (0.80 vs. 0.67, P<0.05). The postoperative survival rate in 90%Hx+Bev group showed tendency to improve compared to that in 90%Hx group (75% vs. 50%, P=0.19).

Conclusions: The administration of bevacizumab seven days before hepatectomy did not significantly affect the liver functions and liver regeneration rate. These findings suggest that hepatectomy might be safe and feasible after the use of bevacizumab.

No significant financial relationships to disclose.

Effect of a histone deacetylase inhibitor on antitumor effect of gemcitabine to focus the gene network of ingenuity pathways analysis

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Background: Histone deacetylase (HDAC) is strongly associated with epigenetic regulation and carcinogenesis, and its inhibitors induce the differentiation or apoptosis of cancer cells. Valproic acid (VPA) is one of the clinically available HDAC inhibitors. We previously showed that VPA augmented antitumor effect of GEM in choalngiocarcinoma cell line (2010 GI Symposium); this time, we performed microarray analysis and Ingenuity Pathways Analysis (IPA) to identify the systematic mechanism of the augmentative effect of VPA.

Methods: Human cholangiocarcinoma cell line (HuCCT1) was used. The anticancer effects of VPA or gemcitabine (GEM), and the effects of VPA combined with GEM were studied by MTT assay. We divided the following four groups: control group, VPA group, GEM group, VPA plus GEM combination group. The gene expressions of p21, HDAC, VEGF, and HIF-1 were evaluated by RT-PCR. And, the microarray analysis was performed, the genes were picked up using Gene Spring GX10, and then IPA was performed.

Results: In GEM alone group, no effect of GEM was observed in dose of 5 mm, and 16% of proliferation-inhibitory effects were observed in dose of 10 nm. In VPA alone group, no effect of VPA was observed in dose of 0.5 mm, and 12%, 35%, and 67% of proliferation-inhibitory effects were observed in dose of 1.0, 5.0, and 10mm, respectively. GEM (5 nm) and VPA (0.5 mm) reduced by 23%, which significantly augmented the anticancer effect of GEM alone or VPA alone (p<0.01). Furthermore, GEM combined with VPA upregulated the p21 expression compared with single agent (p<0.05). And, in regard to microarray analysis, we analyzed in 28,869 genes. The 24 genes were picked up with the comparison between VPA group and VPA plus GEM combination group using Gene Spring GX10, and the gene network of the cellular development containing the gene relevant to the differentiation of cancer cell, HLA-DR, was formed with IPA.

Conclusions: VPA augmented the effects of anticancer agents in a cholangiocarcinoma cell line. Such effects may be owing to the gene network of the cellular development. HDAC inhibitor may have the effect of the differentiation of cancer cell.

No significant financial relationships to disclose.

Role of histone deacetylase expression on regulating cancer stem cells in intrahepatic cholangiocarcinoma

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Background: Histone deacetylase (HDAC) modulates gene expressions by chromatin remodeling during malignant transformation, and showed malignant behavior in intrahepatic cholangiocarcinoma (IHCC) (ASCO GI 2008). HDAC inhibitors have recently been found to repress the function of hypoxia inducible factors (HIF) through inducing hyperacetylation of histones. We also reported that the correlation between the expression of CD133, which was one of the cancer stem cell marker, and HIF-1α in IHCC (J Gastroenterol. 2010), and hypothesized that the cancer stem cell could be regulated by histone acetylation through the HIF-1α pathway. The aim of this study was to elucidate the potential mechanism of HDAC for the regulation of malignant behavior including the cancer stem cell in IHCC.

Methods: Thirty-five patients with IHCC who underwent hepatic resection were evaluated. The expressions of HDAC1 (sc-6298 Santa Cruz Biotechnology, USA), HIF-1α (NB100-105 Novus Biologicals, USA) and CD133 (Ab27699 Abcam Inc, UK) were determined immunohistochemically, and the patients were divided into two groups: HDAC1 positive group (n=21); and negative group (n=14). Clinicopathological variables including HIF-1α and CD133 expressions were analyzed according to these expressions.

Results: The HDAC1 expression correlated significantly with higher stage, lymph node metastasis, and vascular invasion. The prognosis in the HDAC1 positive group was poorer than in the HDAC1 negative group (5-year survival: 77.9% vs. 7.9%, p=0.001). In the multivariate analysis, HDAC1 positive expression was identified as the only independent prognostic factor for disease free survival (Hazard Ratio: 7.194, p=0.0018). There was a significant correlation between HDAC1 expression and HIF-1α expression (p=0.007), and also between HIF-1α expression and CD133 expression (p=0.10). Furthermore, co-expressions of these markers in same cancer cells were proven by immunofluorescent staining in the serial section.

Conclusions: The findings suggested that histone acetylation regulated cancer stem cell through the HIF-1α pathway; therefore, HDAC1 might be a possible promising molecular target in IHCC.

No significant financial relationships to disclose.

The role of endothelium-derived nitric oxide in relaxations to levcromakalim in the rat aorta

The present study was designed to examine the role of basally released nitric oxide in relaxations to an ATP-sensitive K+ channel opener. Whether relaxations to levcromakalim are modulated by endothelial removal or the inhibitors of vasodilator effects of endothelium-derived nitric oxide, were investigated in the rat aorta. During contractions to phenylephrine (3 x 10(-7) to 10(-6) M), levcromakalim (10(-8) to 10(-5) M) or a nitric oxide donor, 1-hydroxy-2-oxo-3-(N-methyl-3-aminopropyl)-3-methyl-1-triazene (NOC-7, 10(-9) to 10(-5) M), was added in a cumulative fashion. Relaxations to levcromakalim (10(-8) to 10(-5) M) were significantly reduced by the endothelium-removal. In aortas with endothelium, relaxations in response to levcromakalim were decreased by selective inhibitors of nitric oxide synthase (N(G)-nitro-L-arginine methyl ester, 10(-4) M) and soluble guanylate cyclase (1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one; ODQ, 10(-5) M) and a scavenger of nitric oxide (carboxy-PTIO, 10(-3) M). Relaxations to levcromakalim in aortas treated with these inhibitors are comparable to those seen in aortas without endothelium. KCl (30 mM) and an ATP-sensitive K+ channel inhibitor, glibenclamide (10(-5) M), abolished relaxations to levcromakalim in aortas with or without endothelium, whereas glibenclamide did not alter relaxations to NOC-7 (10(-9) to 10(-5) M) in aortas without endothelium. These results suggest that in rat aortas, inhibition of vasodilator effects of basally released nitric oxide can reduce relaxations via ATP-sensitive K+ channels, although these channels do not mediate relaxations to exogenously applied nitric oxide.

Assessment of the gas exchange function of the middle ear using nitrous oxide. A preliminary study

A method for assessing the gas exchange through the middle ear (ME) mucosa using nitrous oxide is introduced. Increases in the ME pressure was determined by a tympanogram or a micropressure sensor inserted into the mastoid cavity during ear surgery under general anesthesia using 67% nitrous oxide, 33% oxygen, and sevoflurane on 30 normal ears, 12 ears with otitis media with effusion (OME), and 3 postoperative ears with chronic adhesive otitis media or cholesteatoma. All the 30 normal ears except one showed varying pressure increase, and an inverse correlation was observed between pressure increase and area of mastoid on radiographs. Pressure increase was observed in 6 (50%) ears with OME, and this finding correlated well with the presence or absence of air space in the ME on computed tomography images examined preoperatively, on ears which had ear surgery, the presence or absence of pressure increase correlated with the degree of previous surgical intervention on the mastoid. The rationale and possibility of clinical application of this method is discussed.

Impact of stress on serum gastrin in Zollinger-Ellison syndrome

We report an impressive case with Zollinger-Ellison syndrome (ZES), in which stress-induced sympathetic discharge influenced serum gastrin. Our patient was a 35-yr-old female who complained of frequent and massive vomiting (more than 4000 ml of gastric juice) which was aggravated especially by psychosocial stress. Basal hypergastrinemia (1900 pg/ml) was found after the admission. The most striking finding was that laboratory stress dramatically increased serum gastrin (from 1900 to 5400 pg/ml) and plasma noradrenaline (from 180 to 1130 pg/ml). Mental arithmetic stress further enhanced hypergastrinemia (5800 pg/ml) with a concomitant increase in plasma noradrenaline (1240 pg/ml). Neostigmine (10 micrograms/kg im) also increased serum gastrin up to 6100 pg/ml but propranolol (40 micrograms/kg i.v.) reduced these elevations (noradrenaline: 990 pg/ml, gastrin: 5000 pg/ml). In this case, the effect of stress on serum gastrin mimicked the effect of catecholamine infusion in ZES. These findings suggest that psychological stress induces serum gastrin secretion via beta-adrenoceptor with exacerbation of symptoms in some cases with ZES.

Increased level/dose ratio of amphotericin-B in premature infants with renal failure

We introduced continuous intravenous infusion of amphotericin-B (AMPH-B) to extremely low birthweight (ELBW) infants (< 1000 g) with or without renal failure as a single agent for treating definite or probable systemic candidiasis. The species of Candida isolated from blood or tracheal aspirate or urine were C. albicans in seven infants, C glabrata in two, C. tropicalis in one and C. parapsilosis in one. The minimal inhibitory concentrations (MIC) of AMPH-B required against these isolates were less than 0.2 micrograms/mL except for that against one strain of C. albicans (0.78 microgram/mL). Serum AMPH-B levels were 0.31-0.78 (0.51 +/- 0.14) micrograms/mL when doses of 0.2-0.55 (0.32 +/- 0.11) mg/kg per day were being administered. The serum level was higher than the MIC of each isolate in all but one infant who died of disseminated intravascular coagulation and Candida pneumonia. Another infant died of congenital heart disease. The other nine infants survived. The serum level showed no correlation with the daily dose. The ratio of the serum level to the daily dose (L/D ratio) showed a significant correlation to serum creatinine (r = 0.787) and the linear regression curve followed the equation: L/D ratio = 0.223 x serum creatinine + 1.11 (P < 0.01). Few adverse effects due to AMPH-B were noted. Our data may give a simple reference to serum AMPH-B levels during continuous intravenous infusion from the dose and the serum creatinine level.

Case report: reversal of severe leukopenia by granulocyte colony-stimulating factor in anorexia nervosa

Recent attempts to reduce weight by patients with anorexia nervosa have sometimes led to life-threatening hematologic complications. This report describes an instance in which a patient with anorexia nervosa and pancytopenia drastically improved with treatment that included administration of granulocyte colony-stimulating factor. The patient had lost 27 kg of body weight within 8 months. Even after admission, the blood cell count continued to decrease rapidly as follows: platelet, from 244 x 10(3)/microliters to 44 x 10(3)/microliters; erythrocyte, from 4.04 x 10(6)/microliters to 2.58 x 10(6)/microliters; and leukocyte, from 4.8 x 10(3)/microliters to 1.6 x 10(3)/microliters (granulocyte, 0.8 x 10(3)/microliters). Complications included pneumomediastinum, pneumothorax, purpura, petechiae, hepatomegaly, fever, gangrenous stomatitis, and somnolence. Bone marrow aspiration disclosed absence of fat cells, marrow hypoplasia, and infiltration of the mature lymphocytes. Intravenous hyperalimentation, blood transfusion, gamma-globulin, and antibiotics were administered, but leukopenia and fever remained. However, administration of recombinant human granulocyte colony-stimulating factor dramatically reversed the leukopenia and fever. With careful nutrition therapy, the patient's blood cell count and bone marrow normalized by the time of discharge. It was concluded that severe hematologic disorders may occur in patients with anorexia nervosa, and advanced treatment may be required to save the patient's life.

Impact of stress on alcoholic liver injury; a histopathological study

Certain behaviors can have an influence on the cause and progression of liver disorders. To clarify the relation between histopathological change of the liver and psychosocial stress, behavioral traits, and psychological state, patients with fatty liver (n = 14) were compared with patients with chronic hepatitis (n = 16). Both groups were alcohol-induced without other causes and consumed the same dose of alcohol. By morphometric methods, fat deposit ratio (FDR) and degree of liver damage (DLD) which reflects lobular fibrosis, inflammatory cell infiltration, and necrosis were evaluated. Life Change Unit scores from the Social Readjustment Rating Scale were significantly higher in chronic hepatitis than in fatty liver (p less than 0.001). DLD was significantly correlated with Life Change Unit (r = 0.59, p less than 0.01). It is suggested that psychosocial stress is one of the aggravating factors of fibrosis and inflammatory change of the liver which is previously damaged by alcohol in man just like the rat liver following stress.