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Liver plays a major role in maintaining glucose homeostasis in mammals. Under fasting conditions, hepatic glucose production is critical as a source of fuel to maintain the basic functions in other tissues, including skeletal muscle, red blood cells, and the brain. Fasting hormones glucagon and cortisol play major roles during the process, in part by activating the transcription of key enzyme genes in the gluconeogenesis such as phosphoenol pyruvate carboxykinase (PEPCK) and glucose 6 phosphatase catalytic subunit (G6Pase). Conversely, gluconeogenic transcription is repressed by pancreatic insulin under feeding conditions, which effectively inhibits transcriptional activator complexes by either promoting post-translational modifications or activating transcriptional inhibitors in the liver, resulting in the reduction of hepatic glucose output. The transcriptional regulatory machineries have been highlighted as targets for type 2 diabetes drugs to control glycemia, so understanding of the complex regulatory mechanisms for transcription circuits for hepatic gluconeogenesis is critical in the potential development of therapeutic tools for the treatment of this disease. In this review, the current understanding regarding the roles of two key transcriptional activators, CREB and FoxO1, in the regulation of hepatic gluconeogenic program is discussed. [BMB Reports 2013; 46(12): 567-574]

Postprandial insulin plays a critical role in suppressing hepatic glucose production to maintain euglycemia in mammals. Insulin-dependent activation of protein kinase B (Akt) regulates this process, in part, by inhibiting FoxO1-dependent hepatic gluconeogenesis by direct phosphorylation and subsequent cytoplasmic exclusion. Previously, it was demonstrated that protein arginine methyltransferase 1 (PRMT1)-dependent arginine modification of FoxO1 interferes with Akt-dependent phosphorylation, both in cancer cells and in the Caenorhabditis elegans model, suggesting that this additional modification of FoxO1 might be critical in its transcriptional activity. In this study, we attempted to directly test the effect of arginine methylation of FoxO1 on hepatic glucose metabolism. The ectopic expression of PRMT1 enhanced messenger RNA levels of FoxO1 target genes in gluconeogenesis, resulting in increased glucose production from primary hepatocytes. Phosphorylation of FoxO1 at serine 253 was reduced with PRMT1 expression, without affecting the serine 473 phosphorylation of Akt. Conversely, knockdown of PRMT1 promoted an inhibition of FoxO1 activity and hepatic gluconeogenesis by enhancing the phosphorylation of FoxO1. In addition, genetic haploinsufficiency of Prmt1 reduced hepatic gluconeogenesis and blood-glucose levels in mouse models, underscoring the importance of this factor in hepatic glucose metabolism in vivo. Finally, we were able to observe an amelioration of the hyperglycemic phenotype of db/db mice with PRMT1 knockdown, showing a potential importance of this protein as a therapeutic target for the treatment of diabetes. Conclusion: Our data strongly suggest that the PRMT1-dependent regulation of FoxO1 is critical in hepatic glucose metabolism in vivo. (HEPATOLOGY 2012)

Diet-induced obesity is a major contributing factor to the progression of hepatic insulin resistance. Increased free fatty acids in liver enhances endoplasmic reticulum (ER) stress and production of reactive oxygen species (ROS), both are directly responsible for dysregulation of hepatic insulin signaling. BI-1, a recently studied ER stress regulator, was examined to investigate its association with ER stress and ROS in insulin resistance models. To induce obesity and insulin resistance, BI-1 wild type and BI-1 knock-out mice were fed a high-fat diet for 8 weeks. The BI-1 knock-out mice had hyperglycemia, was associated with impaired glucose and insulin tolerance under high-fat diet conditions. Increased activity of NADPH-dependent CYP reductase-associated cytochrome p450 2E1 (CYP2E1) and exacerbation of ER stress in the livers of BI-1 knock-out mice was also observed. Conversely, stable expression of BI-1 in HepG2 hepatocytes was shown to reduce palmitate-induced ER stress and CYP2E1-dependent ROS production, resulting in the preservation of intact insulin signaling. Stable expression of CYP2E1 led to increased ROS production and dysregulation of insulin signaling in hepatic cells, mimicking palmitate-mediated hepatic insulin resistance. We propose that BI-1 protects against obesity-induced hepatic insulin resistance by regulating CYP2E1 activity and ROS production.

Although brown adipose tissue is important with regard to energy balance, the molecular mechanism of brown adipocyte differentiation has not been extensively studied. Specifically, regulation factors at the level of protein modification are largely unknown. In this study, we examine the changes in the expression level of enzymes which are involved in protein lysine methylation during brown adipocyte differentiation. Several enzymes, in this case SUV420H2, PRDM9, MLL3 and JHDM1D, were found to be up-regulated. On the other hand, Set7/9 was significantly down-regulated. In the case of SUV420H2, the expression level increased sharply during brown adipocyte differentiation, whereas the expression of SUV420H2 was marginally enhanced during the white adipocyte differentiation. The knock-down of SUV420H2 caused the suppression of brown adipocyte differentiation, as compared to a scrambled control. These results suggest that SUV420H2, a methyltransferase, is involved in brown adipocyte differentiation, and that the methylation of protein lysine is important in brown adipocyte differentiation. [BMB Reports 2016; 49(7): 388-393].

Brown adipose tissue, which is mainly composed of brown adipocytes, plays a key role in the regulation of energy balance via dissipation of extra energy as heat, and consequently counteracts obesity and its associated-disorders. Therefore, brown adipocyte differentiation should be tightly controlled at the multiple regulation steps. Among these, the regulation at the level of post-translational modifications (PTMs) is largely unknown. Here, we investigated the changes in the expression level of the enzymes involved in protein lysine methylation during brown adipocyte differentiation by using quantitative real-time PCR (qPCR) array analysis. Several enzymes showing differential expression patterns were identified. In particular, the expression level of methyltransferase Set7/9 was dramatically repressed during brown adipocyte differentiation. Although there was no significant change in lipid accumulation, ectopic expression of Set7/9 led to enhanced expression of several key thermogenic genes, such as uncoupling protein-1 (UCP-1), Cidea, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), and PR domain containing 16 (PRDM16). In contrast, knockdown of endogenous Set7/9 led to significantly reduced expression of these thermogenic genes. Furthermore, suppressed mitochondrial DNA content and decreased oxygen consumption rate were also detected upon Set7/9 knockdown. We found that p53 acetylation was regulated by Set7/9-dependent interaction with Sirt1. Based on these results, we suggest that Set7/9 acts as a fine regulator of the thermogenic program during brown adipocyte differentiation by regulation of p53 acetylation. Thus, Set7/9 could be used as a valuable target for regulating thermogenic capacity and consequently to overcome obesity and its related metabolic diseases.

EGFR is a key player in cell proliferation and survival signaling, and its sorting into MVBs for eventual lysosomal degradation is controlled by the coordination of multiple ESCRT complexes on the endosomal membrane. HD-PTP is a cytosolic protein tyrosine phosphatase, and is associated with EGFR trafficking by interacting with the ESCRT-0 protein STAM2 and the ESCRT-III protein CHMP4B via its N-terminal Bro1 domain. Intriguingly, the homologous domain of two other human Bro1 domain-containing proteins, Alix and Brox, binds CHMP4B but not STAM2, despite their high structural similarity. To elucidate this binding specificity, we determined the complex structure of the HD-PTP Bro1 domain bound to the STAM2 core region. STAM2 binds to the hydrophobic concave pocket of the HD-PTP Bro1 domain, as CHMP4B does to the pocket of Alix, Brox, or HD-PTP but in the opposite direction. Critically, Thr145 of HD-PTP, corresponding to Lys151 of Alix and Arg145 of Brox, is revealed to be a determinant residue enabling this protein to bind STAM2, as the Alix- or Brox-mimicking mutations of this residue blocks the intermolecular interaction. This work therefore provides the structural basis for how HD-PTP recognizes the ESCRT-0 component to control EGFR sorting.

Abnormal adipocyte differentiation is implicated in the development of metabolic disorders such as obesity and type II diabetes. Thus, an in-depth understanding of the molecular mechanisms associated with adipocyte differentiation is the first step in overcoming obesity and its related metabolic diseases. Here, we examined the role of c-Jun as a transcription factor in adipocyte differentiation. c-Jun overexpression in murine 3T3-L1 preadipocytes significantly inhibited adipocyte differentiation. In addition, the expression level of KLF15, an upstream effector of the key adipogenic factors C/EBPα and PPARγ, was decreased upon the ectopic expression of c-Jun. We found that c-Jun inhibited basal and glucocorticoid receptor (GR)-induced promoter activities of KLF15. c-Jun directly bound near the glucocorticoid response element (GRE) sites in the KLF15 promoter and inhibited adjacent promoter occupancies of GR. Furthermore, the restoration of KLF15 expression in 3T3-L1 cells with the stable ectopic expression of c-Jun partially rescued adipocyte differentiation. Our results demonstrate that c-Jun can suppress adipocyte differentiation through the down-regulation of KLF15 at the transcriptional level. This study proposes a novel mechanism by which c-Jun regulates adipocyte differentiation.

Dysregulation of lipid metabolism is a key feature of metabolic disorder related to side effects of antipsychotic drugs. Here, we investigated the molecular mechanism by which second-generation atypical antipsychotic drugs (AAPDs) affect hepatic lipid metabolism in liver. AAPDs augmented hepatic lipid accumulation by activating expression of sterol regulatory element-binding protein (SREBP) transcription factors, with subsequent induction of downstream target genes involved in lipid and cholesterol synthesis in hepatocytes. We confirmed the direct involvement of SREBPs on AAPD-induced expression of lipogenic and cholesterogenic genes by utilization of adenovirus for dominant negative SREBP (Ad-SREBP-DN). Interestingly, AAPDs significantly decreased phosphorylation of AMPKα and expression of fatty acid oxidation genes. Treatment of constitutive active AMPK restored AAPD-mediated dysregulation of genes involved in both lipid synthesis and fatty acid oxidation. Moreover, AAPDs decreased transcriptional activity of PPARα, a critical transcriptional regulator for controlling hepatic fatty acid oxidation, via an AMPK-dependent manner. Close investigations revealed that mutations at the known p38 MAPK phosphorylation sites (S6/12/21A), but not mutations at the putative AMPKα phosphorylation sites (S167/373/453A), block AAPD-dependent reduction of PPARα transcriptional activity, suggesting that p38 MAPK might be also involved in the regulatory pathway as a downstream effector of AAPDs/AMPK. Taken together, these data suggest that AAPD-stimulated hepatic dysregulation of lipid metabolism could result from the inhibition of AMPK activity, and pharmaceutical means to potentiate AMPK activity would contribute to restore hepatic lipid homeostasis that occurs during AAPD treatment.

Annexin A2 (ANXA2) expression is highly upregulated in many types of cancer. Although cell surface localization of ANXA2 has been reported to have a critical role in the progression and metastasis of a variety of tumors, including pancreatic cancer, the biological role of intracellular ANXA2 is not fully understood. Herein the role of intracellular ANXA2 was investigated in a pancreatic cancer cell line. We first determined whether ANXA2 is involved in NF-κB signaling pathways. ANXA2 bound to the p50 subunit of NF-κB in a calcium-independent manner, and the ANXA2–p50 complex translocated into the nucleus. Furthermore, ANXA2 increased the transcriptional activity of NF-κB in both the resting and activated states and upregulated the transcription of several target genes downstream of NF-κB, including that encoding interleukin (IL)-6, which contributes to anti-apoptotic signaling. In Mia-Paca2 cells, we determined the effects of wild-type ANXA2 and an ANXA2 mutant, Y23A, which suppresses the cell surface localization, on upregulation of NF-κB transcriptional activity and secretion of IL-6. Both wild-type and Y23A ANXA2 induced anti-apoptotic effects in response to treatment with tumor necrosis factor-α or gemcitabine. Based on these results, we suggest that ANXA2 mediates resistance to gemcitabine by directly increasing the activity of NF-κB. Collectively, these data may provide additional information about the biological role of ANXA2 in pancreatic cancer and suggest that ANXA2 is a potential biomarker for the drug resistance phenotype and a candidate therapeutic target for the treatment of pancreatic cancer.

Obesity is a chronic disease that is associated with significantly increased levels of risk of a number of metabolic disorders. Despite these enhanced health risks, the worldwide prevalence of obesity has increased dramatically over the past few decades. Obesity is caused by the accumulation of an abnormal amount of body fat in adipose tissue, which is composed mostly of adipocytes. Thus, a deeper understanding of the regulation mechanism of adipose tissue and/or adipocytes can provide a clue for overcoming obesity-related metabolic diseases. In this review, we describe recent advances in the study of adipose tissue and/or adipocytes, focusing on proteomic approaches. In addition, we suggest future research directions for proteomic studies which may lead to novel treatments of obesity and obesity-related diseases.

Protein tyrosine phosphatases have been recognized as critical components of multiple signaling regulators of fundamental cellular processes, including differentiation, cell death, and migration. In this study, we show that dual specificity phosphatase 4 (DUSP4) is crucial for neuronal differentiation and functions in the neurogenesis of embryonic stem cells (ESCs). The endogenous mRNA and protein expression levels of DUSP4 gradually increased during mouse development from ESCs to postnatal stages. Neurite outgrowth and the expression of neuron-specific markers were markedly reduced by genetic ablation of DUSP4 in differentiated neurons, and these effects were rescued by the reintroduction of DUSP4. In addition, DUSP4 knockdown dramatically enhanced extracellular signal-regulated kinase (ERK) activation during neuronal differentiation. Furthermore, the DUSP4-ERK pathway functioned to balance calcium signaling, not only by regulating Ca(2+)/calmodulin-dependent kinase I phosphorylation, but also by facilitating Cav1.2 expression and plasma membrane localization. These data are the first to suggest a molecular link between the MAPK-ERK cascade and calcium signaling, which provides insight into the mechanism by which DUSP4 modulates neuronal differentiation.

The epithelial cell adhesion molecule (EpCAM, also known as CD326) is a transmembrane glycoprotein that is specifically detected in most adenocarcinomas and cancer stem cells. In this study, we performed a Cell systematic evolution of ligands by exponential enrichment (SELEX) experiment to isolate the aptamers against EpCAM. After seven round of Cell SELEX, we identified several aptamer candidates. Among the selected aptamers, EP166 specifically binds to cells expressing EpCAM with an equilibrium dissociation constant (Kd) in a micromolar range. On the other hand, it did not bind to negative control cells. Moreover, EP166 binds to J1ES cells, a mouse embryonic stem cell line. Therefore, the isolated aptamers against EpCAM could be used as a stem cell marker or in other applications in both stem cell and cancer studies.

Cost of daily treatment of Dutasteride is $1560 per year while once a week treatment is $206 per year. CONCLUSIONS: Non-daily treatment was more cost effective. PSA is lowered most by daily usage. The average number of biopsies per group was not different in the study period. Biopsy interval in the non-daily group was twice as long as the daily group. Cancer incidence in the non-daily group surprisingly was at least half compared to daily and no cytoreduction groups. Although not statistically significant, higher grade tumors were seen in the daily and no treatment groups.

INTRODUCTION AND OBJECTIVES: We evaluated the efficacy of a combination treatment of desmopressin and propiverine for treating children with monosymptomatic primary nocturnal enuresis. METHODS: A total of 53 children aged 6 to 15 years old with monosymptomatic nocturnal enuresis were enrolled in this prospective study. Children with a minimum of 3 wet nights weekly were included. Children were randomly assigned groups and treated with desmopressin 0.2mg, or a combination of desmopressin plus propiverine 10mg. Of these patients 43 (31 boys and 12 girls, mean age 8.4 2.5 years, range 4 to 13) were followed for more than 6 months. Efficacy was measured at 1, 3 and 6 months in terms of average enuretic frequency after treatment. RESULTS: Of the 43 children finally analyzed, 23 received combination therapy of desmopressin and propiverine and 20 received desmopressin alone. The frequency of nocturnal enuresis at baseline in the monotherapy group and combination therapy group was similar (5.45 1.57 vs 5.82 1.44). However, a decrease of the nocturnal enuresis was significantly pronounced in the combination group after 6 months treatment than in monotherpy group (2.2 1.01 vs 1.29 0.67). Combination therapy produced better outcomes than monotherapy in terms of the number of nocturnal enuresis episodes (p 0.017). Adverse events were minimal. CONCLUSIONS: Combination therapy with desmopressin plus propiverine for the treatment of monosymptomatic nocturnal enuresis was well tolerated, and gave effective results in reducing enuresis episodes rather than a single therapy of desmopressin in children.

Glucose is a primary fuel for generating energy in basic daily activities. Thus, glucose homeostasis is tightly regulated by counter-regulatory hormones such as glucagon, cortisol, and insulin, which affect key organs including liver, skeletal muscle, pancreas, and adipocytes. Among metabolic tissues, liver plays a critical role in controlling glucose production under various hormonal and metabolic cues. Under fasting, acute activation of both glycogenolysis and gluconeogenesis is achieved by post-translational modification or allosteric activation of key rate-limiting enzymes, thereby enabling enhanced glucose production from the liver to maintain glucose homeostasis. More prolonged fasting or starvation leads to the chronic activation of gluconeogenesis that requires increased expression of key enzymes in the pathway, which is turned off under feeding conditions by the molecular events that are initiated by insulin. This process is normally achieved by the regulation of gene expression at the level of transcription. Recently, the transcriptional regulators of hepatic gluconeogenesis are considered as potential therapeutic targets for the treatment of type 2 diabetes. In this review, we would like to discuss the current knowledge regarding the key transcriptional activators and inhibitors of hepatic gluconeogenic program to provide the better insight into the control of glycemia in the disease status.

Peripheral insulin resistance contributes to the development of type 2 diabetes. TCF7L2 has been tightly associated with this disease, although the exact mechanism was largely elusive. Here we propose a novel role of TCF7L2 in hepatic glucose metabolism in mammals. Expression of medium and short isoforms of TCF7L2 was greatly diminished in livers of diet-induced and genetic mouse models of insulin resistance, prompting us to delineate the functional role of these isoforms in hepatic glucose metabolism. Knockdown of hepatic TCF7L2 promoted increased blood glucose levels and glucose intolerance with increased gluconeogenic gene expression in wild-type mice, in accordance with the PCR array data showing that only the gluconeogenic pathway is specifically up-regulated upon depletion of hepatic TCF7L2. Conversely, overexpression of a nuclear isoform of TCF7L2 in high-fat diet-fed mice ameliorated hyperglycemia with improved glucose tolerance, suggesting a role of this factor in hepatic glucose metabolism. Indeed, we observed a binding of TCF7L2 to promoters of gluconeogenic genes; and expression of TCF7L2 inhibited adjacent promoter occupancies of CREB, CRTC2, and FoxO1, critical transcriptional modules in hepatic gluconeogenesis, to disrupt target gene transcription. Finally, haploinsufficiency of TCF7L2 in mice displayed higher glucose levels and impaired glucose tolerance, which were rescued by hepatic expression of a nuclear isoform of TCF7L2 at the physiological level. Collectively, these data suggest a crucial role of TCF7L2 in hepatic glucose metabolism; reduced hepatic expression of nuclear isoforms of this factor might be a critical instigator of hyperglycemia in type 2 diabetes., Author Summary Previous genome-wide association studies revealed that TCF7L2 is a strong candidate for a type 2 diabetes gene. However, the direct involvement of TCF7L2 on hepatic glucose metabolism has been elusive to date. Here we show that TCF7L2 is critical in mediating transcriptional control of hepatic glucose production. We found that hepatic expression of nuclear isoforms of TCF7L2 was reduced in mouse models of insulin resistance. Acute depletion of TCF7L2 in the liver promoted glucose intolerance and up-regulation of gluconeogenic genes, while ectopic expression of TCF7L2 in DIO mice improved glucose tolerance. TCF7L2 was shown to bind to the gluconeogenic promoters, thereby interfering with the promoter occupancies of both CREB/CRTC2 and FoxO1 on their cognate sites. Furthermore, TCF7L2 haploinsufficiency promoted higher glucose levels with impaired glucose tolerance and increased hepatic glucose production in mice, and adenovirus-mediated TCF7L2 expression in the liver reversed the phenotype. We propose that TCF7L2 is a critical player in regulating glucose homeostasis in mammals by modulating hepatic glucose production.

Nanoparticles are of great interest due to their wide variety of biomedical and bioengineering applications. However, they affect cellular differentiation and/or intracellular signaling when applied and exposed to target organisms or cells. The brown adipocyte is a cell type important in energy homeostasis and thus closely related to obesity. In this study, we assessed the effects of silica nanoparticles (SNPs) on brown adipocyte differentiation. The results clearly showed that brown adipocyte differentiation was significantly repressed by exposure to SNPs. The brown adipocyte-specific genes as well as mitochondrial content were also markedly reduced. Additionally, SNPs led to suppressed p38 phosphorylation during brown adipocyte differentiation. These effects depend on the size of SNPs. Taken together, these results lead us to suggest that SNP has anti-brown adipogenic effect in a size-dependent manner via regulation of p38 phosphorylation.

Objective To identify proteomic biomarkers in amniotic fluid (AF) that can distinguish preeclampsia (PE) from chronic hypertension (CHTN) and normotensive controls (CTR). Methods AF from women with PE, CHTN, and CTR were subjected to proteomic analysis by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. Results Proteomic profiling of AF identified 2 biomarkers: peak X (17399.11 Da), which distinguished PE from CTR, and peak Y (28023.34 Da), which distinguished PE and CHTN from CTR. High performance liquid chromatography fractions containing the biomarkers were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and in-gel tryptic digestion. The biomarkers were matched to proapolipoprotein A-I (peak Y) and a functionally obscure peptide, SBBI42 (peak X). Western blot analysis confirmed that AF from PE and CHTN had higher proapolipoprotein A-I levels than CTR. Conclusion Proteomic analysis of AF can distinguish PE from CHTN and CTR. The discriminatory proteins were identified as proapolipoprotein A-I and SBBI42.

Decidualization of human endometrial stromal (ES) cells plays a critical role in successful uterine implantation. Therefore, monitoring of the behavior of human ES cells may provide the clue for early detection of a uterine abnormality such as sterility and abortion. Monitoring of decidualization in vitro cell culture system fundamentally depends on expression of the definite biomarkers. In this study, we tried to uncover novel marker proteins of 8-bromo-cyclic adenosine monophosphate (8-Br-cAMP)-induced decidualization in human ES cells using the surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Samples were divided into three groups; control human ES cells (n=7), ES cells treated with 8-Br-cAMP (n=7 per each treatment, treated for 3, 6, 9, or 12 days), and cells from which 8-Br-cAMP was withdrawn for 3 days (n=7) or 6 days (n=7) after 8-Br-cAMP treatment for 6 days. Differential expressions between non-decidual control cells and 8-Br-cAMP-induced decidual cells were observed in the peaks of 9787.058 Da, 10115.45 Da, and 24031.25 Da, detected by H4 ProteinChip, and in the peaks of 10833.08 Da, 22440.88 Da, and 32777.38 Da, detected by CM10 ProteinChip. The expression patterns of these decidual markers are expected to provide invaluable information in monitoring cellular development, and further identification of these proteins may hopefully offer precious means for clinical research and therapeutic purposes.

We have previously reported that Fas-resistant A20 cells (FasR) have phospholipase D (PLD) activity upregulated by endogenous PLD2 overexpression. In the present study, we investigated how overexpressed PLD2 in FasR could generate survival signals by regulating the protein levels of anti-apoptotic Bcl-2 and Bcl-xL. To confirm the effect of PLD2 on Bcl-2 protein levels, we transfected PLD2 into wild-type murine B lymphoma A20 cells. The transfected cells showed markedly the increases in Bcl-2 and Bcl-xL protein levels, and became resistant to Fas-induced apoptosis, similar to FasR. Treatment of wild-type A20 cells with phosphatidic acid (PA), the metabolic end product of PLD2 derived from phosphatidylcholin, markedly increased levels of anti-apoptotic Bcl-2 and Bcl-xL proteins. Moreover, PA-induced expressions of Bcl-2 and Bcl-xL were enhanced by propranolol, an inhibitor of PA phospholydrolase (PAP), whereas completely blocked by mepacrine, an inhibitor of phospholipase A2 (PLA2), suggesting that PLA2 metabolite of PA is responsible for the increases in Bcl-2 and Bcl-xL protein levels. We further confirmed the involvement of arachidonic acid (AA) in PA-induced survival signals by showing that 1,2-dipalmitoyl-sn-glycero-3-phosphate (DPPA), PA without AA, was unable to increase Bcl-2 and Bcl-xL proteins. Moreover, PA notably increased cyclooxygenase (COX)-2 protein expression, and PA-induced expression of both Bcl-2 and Bcl-xL was inhibited by NS-398, a specific inhibitor of COX-2. Taken together, these findings demonstrate that PA generated by PLD2 plays an important role in cell survival during Fas-mediated apoptosis through the increased Bcl-2 and Bcl-xL protein levels which resulted from PLA2 and AA-COX2 pathway. J. Cell. Biochem. 101: 1409–1422, 2007. © 2007 Wiley-Liss, Inc.

We have previously isolated a 22 kDa protein from a rat brain which was found to be involved in activating phospholipsae D (PLD), and identified the protein as hippocalcin through sequence analysis. Nevertheless, the function of hippocalcin for PLD activation still remains to be resolved. Here, we proposed that hippocalcin was involved in extracellular signal-regulated kinase (ERK)-mediated PLD2 expression. To elucidate a role of hippocalcin, we made hippocalcin transfected NIH3T3 cells and showed that the expression of PLD2 and basal PLD activity were increased in hippocalcin transfected cells. We performed PLD assay with dominant negative PLD2 (DN-PLD2) and hippocalcin co-transfected cells. DN-PLD2 suppressed increase of basal PLD activity in hippocalcin transfected cells, suggesting that increased basal PLD activity is due to PLD2 over-expression. Hippocalcin is a Ca2+-binding protein, which is expressed mainly in the hippocampus. Since it is known that lysophosphatidic acid (LPA) increases intracellular Ca2+, we investigated the possible role of hippocalcin in the LPA-induced elevation of intracellular Ca2+. When the intracellular Ca2+ level was increased by LPA, hippocalcin was translocated to the membrane after LPA treatment in hippocalcin transfected cells. In addition, treatment with LPA in hippocalcin transfected cells markedly potentiated PLD2 expression and showed morphological changes of cell shape suggesting that increased PLD2 expression acts as one of the major factors to cause change of cell shape by making altered membrane lipid composition. Hippocalcin-induced PLD2 expression potentiated by LPA in hippocalcin transfected cells was inhibited by a PI-PLC inhibitor, U73122 and a chelator of intracellular Ca2+, BAPTA–AM suggesting that activation of hippocalcin caused by increased intracellular Ca2+ is important to induce over-expression of PLD2. However, downregulation of PKC and treatment of a chelator of extracellular Ca2+, EGTA had little or no effect on the inhibition of hippocalcin-induced PLD2 expression potentiated by LPA in the hippocalcin transfected cells. Interestingly, when we over-express hippocalcin, ERK was activated, and treatment with LPA in hippocalcin transfected cells significantly potentiated ERK activation. Specific inhibition of ERK dramatically abolished hippocalcin-induced PLD2 expression. Taken together, these results suggest for the first time that hippocalcin can induce PLD2 expression and LPA potentiates hippocalcin-induced PLD2 expression, which is mediated by ERK activation. J. Cell. Biochem. 97: 1052–1065, 2006. © 2005 Wiley-Liss, Inc.

(29.4%), 143 in AH to body (37.5%), and 126 in body (33.1%). Number of consecutive sections of pseudoradial tear were 1 in 100 (26.2%), 2 in 164 (43.0%), 3 in 94 (24.7%), 4 in 21 (5.5%), and 5 in 2 (0.5%). Interobserver agreement was 0.99 for presence and 0.43 for number of sections of pseudoradial tear. Arthroscopies were performed in 96 patients and none of the pseudoradial tears were proven as true radial tears on arthroscopy.

Hemochromatosis is a disorder caused by excessive iron deposition in parenchymal cells that leads to cellular damage and organ dysfunction. The excessive iron overload of secondary hemochromatosis is associated with chronic disorders of erythropoiesis that are treated with prolonged repeated blood transfusions. We experienced two cases of transfusional hemochromatosis involving the pituitary gland, and we report the findings of the MR imaging.

Purpose: We wanted to examine the usefulness of multi-detector CT (MDCT) with multiplanar reformations for evaluating the location, thickness and the presence or absence of intraluminal gas in the normal appendix of adults. Materials and Methods: From December 2004 to June 2005, we evaluated normal appendices in 427 consecutive adult patients who were scanned with 16-slice MDCT. All these patients had no clinical findings of appendicitis. There were 251 men and 176 women. The age range was 19-84 years (mean age: 55 years). The contrast-enhanced MDCT scans during the portal phase were obtained with 0.75 mm detector collimation and they were reviewed with using the multiplanar reconstruction images (3 mm section thickness). The MDCT images of normal appendices on a PACS monitor were retrospectively analyzed. We analyzed the location, thickness and the presence or absence of intraluminal gas by consensus of two abdominal radiologists. The positions of normal appendices were classified as type I (postileal and medial paracecal), type II (subcecal), type III (retrocecal and retrocolic or laterocolic), type IV (preileal and medial colic) and type V (lower pelvic cavity). Results: The five types of appendiceal locations were as follows; type I (n=187; 44%), type II (n=78; 18 %), type III (n=92; 22%), type IV (n=39; 9%) and type V (n=31; 7%). The appendiceal tips in 29 cases (7%) were unusually located in the right subhepatic space, the small bowel mesentery and the right adnexa. The mean thickness of 427 appendices was 5.8±0.9 mm (range: 3.8-9.2 mm). The appendiceal mean thickness was 5.90.9 mm in men and 5.70.9 mm in women (p