ZFAND3 Overexpression in the Mouse Liver Improves Glucose Tolerance and Hepatic Insulin Resistance.

Genome-wide association studies have identified more than 300 loci associated with type 2 diabetes mellitus; however, the mechanisms underlying their role in type 2 diabetes mellitus susceptibility remain largely unknown. Zinc finger AN1-type domain 3 (ZFAND3), known as testis-expressed sequence 27, is a type 2 diabetes mellitus-susceptibility gene. Limited information is available regarding the physiological role of ZFAND3 in vivo. This study aimed to investigate the association between ZFAND3 and type 2 diabetes mellitus. ZFAND3 was significantly upregulated in the liver of diabetic mice compared to wild-type mice. To overexpress ZFAND3, we generated a ZFAND3-expressing adenovirus (Ad) vector using an improved Ad vector exhibiting significantly lower hepatotoxicity (Ad-ZFAND3). Glucose tolerance was significantly improved in Ad-ZFAND3-treated mice compared to the control Ad-treated mice. ZFAND3 overexpression in the mouse liver also improved insulin resistance. Furthermore, gluconeogenic gene expression was significantly lower in primary mouse hepatocytes transduced with Ad-ZFAND3 than those transduced with the control Ad vector. The present results suggest that ZFAND3 improves glucose tolerance by improving insulin resistance and suppressing gluconeogenesis, serving as a potential novel therapeutic target for type 2 diabetes mellitus.

MicroRNA-101 inhibits the expression of Rhes, a striatal-enriched small G-protein, at the post-transcriptional level in vitro.

OBJECTIVE: Ras homolog enriched in striatum (Rhes) is a small GTP-binding protein that is predominantly localized in the striatal region of the brain. Rhes affects various signaling pathways and plays important roles in Huntington's disease development caused by striatal anomalies. However, the mechanism underlying the regulation of Rhes expression is not fully understood. We hypothesized that Rhes expression might be regulated by microRNAs (miRNAs), which are small noncoding RNAs that regulate gene expression by interacting with the 3'-untranslated region (3'UTR) of mRNA. This study therefore investigated the interaction between miRNAs and the Rhes mRNA 3'UTR. RESULTS: The results of luciferase assay showed that miR-101, the miRNA determined to have the highest possibility of interacting with the Rhes mRNA 3'UTR using DIANA-microT, significantly inhibits luciferase activity, suggesting that miR-101 directly targets the Rhes mRNA 3'UTR. Additionally, Rhes protein levels in cultured cells co-transfected with a plasmid containing the complete Rhes cDNA and miR-101 were significantly downregulated by miR-101 as demonstrated by western blot analysis. These results support our hypothesis that Rhes expression is regulated by miRNA and indicate that miR-101 may be a potent modulator of Rhes expression in striatal neurons.

Bergamottin Promotes Adipocyte Differentiation and Inhibits Tumor Necrosis Factor-α-induced Inflammatory Cytokines Induction in 3T3-L1 Cells.

Nowadays, a lot of food ingredients are marketed as dietary supplements for health. Because the effectiveness and mechanisms of these compounds have not been fully characterized, they might have unknown functions. Therefore, we investigated the effect of several food ingredients (Bergamottin, Chrysin, L-Citrulline and ß-Carotene) known as health foods on adipocyte differentiation by using 3T3-L1 preadipocytes. In this study, we found that Bergamottin, a furanocoumarin isolated from grapefruit juice, promotes adipocyte differentiation. In addition, Bergamottin increases the expression of adiponectin, an anti-inflammatory adipokine, and peroxisome proliferator activated receptor γ (PPARγ), a nuclear receptor regulating adipocyte differentiation. Furthermore, the anti-inflammatory activity of Bergamottin was demonstrated by its inhibition of the activation of nuclear factor-κB (NF-κB), an inflammatory transcription factor. Stimulation of mature 3T3-L1 adipocytes by tumor necrosis factor-α (TNF-α) decreased the expression of the endogeneous NF-κB inhibitor, IκBα. Treatment with Bergamottin further decreased the TNF-α-induced change in IκBα expression, suggesting that Bergamottin mediated the inhibition of NF-κB activation. In addition, Bergamottin decreased the TNF-α-induced increase in the mRNA levels of pro-inflammatory adipokines, monocyte chemoattractant protein-1 and interleukin-6. Taken together, our results show that Bergamottin treatment could inhibit inflammatory activity through promoting adipocyte differentiation, which in turn suggests that Bergamottin has the potential to minimize the risk factors of metabolic syndrome.

Inhibitory Effect of Fruit Juices on the Doxorubicin Metabolizing Activity of Carbonyl Reductase 1.

BACKGROUND AND OBJECTIVE: Doxorubicin, an anthracycline anti-cancer drug, is effective for breast cancer and childhood lymphoma. Chronic cardiotoxicity has been known as a critical adverse effect of doxorubicin and is attributed to its metabolite doxorubicinol produced by carbonyl reductase 1 (CBR1, SDR21C1). Some flavonoids have been reported to act as inhibitors for CBR1, therefore, commercially available juices containing flavonoids are likely to be applicable as a prophylactic treatment against doxorubicin-induced cardiotoxicity by suppression of doxorubicinol production. In the study, fruit juices containing flavonoids were investigated for inhibitory effects on CBR1. METHOD: Recombinant CBR1 protein was subjected to in vitro enzymatic assays with/without juices. An apple juice and a grapefruit juice were selected in the present study as candidates capable of inhib-iting CBR1. RESULTS: The enzymatic assays revealed that both juices potently inhibit the CBR1-mediated metabolic conversion of doxorubicin to doxorubicinol in concertation-dependent manner. The concentrations required for obtaining 50% inhibition (IC50) were 0.0012% (v/v) and 0.0014% (v/v) for apple and grapefruit juices, respectively. Additionally, it is worth noting that these juices showed inhibitory effects on doxorubicin metabolism by CBR1 even at very low concentrations (0.0001% (v/v)). CONCLUSION: An apple juice and a grape fruit juice showed strong inhibitory effects on doxorubicin metabolism by CBR1 in vitro. These results suggest that the intake of flavonoid-containing juices can be a promising measure for protection against doxorubicin-induced cardiac toxicity, enabling patients to keep higher adherence with routine use in light of safety, economic performance and stable supply to market.

Identification of a functional antioxidant responsive element in the promoter of the Chinese hamster carbonyl reductase 3 (Chcr3) gene.

CHCR3, a member of the short-chain dehydrogenase/reductase superfamily, is a carbonyl reductase 3 enzyme in Chinese hamsters. Carbonyl reductase 3 in humans has been believed to involve the metabolism and/or pharmacokinetics of anthracycline drugs, and the mechanism underlying the gene regulation has been investigated. In this study, the nucleotide sequence of the Chcr3 promoter was originally determined, and its promoter activity was characterised. The proximal promoter region is TATA-less and GC-rich, similar to the promoter region of human carbonyl reductase 3. Cobalt stimulated the transcriptional activity of the Chcr3 gene. The results of a luciferase gene reporter assay demonstrated that cobalt-induced stimulation required an antioxidant responsive element. Forced expression of Nrf2, the transcription factor that binds to antioxidant responsive elements, enhanced the transcriptional activity of the Chcr3 gene. These results suggest that cobalt induces the expression of the Chcr3 gene via the Nrf2-antioxidant responsive element pathway.

Regulation of human carbonyl reductase 1 (CBR1, SDR21C1) gene by transcription factor Nrf2.

Monomeric carbonyl reductase 1 (CBR1, SDR21C1) is a member of the short-chain dehydrogenase/reductase superfamily and is involved in the metabolism of anthracycline anti-cancer drugs, prostaglandins, and isatin, which is an endogenous inhibitor of monoamine oxidases. Additionally, cancer progression may be partly regulated by CBR1. In the present study, we screened more than 10 drugs for the induction of the human CBR1 gene to investigate its regulation. Of the drugs, butylated hydroxyanisole (BHA) was found to be an inducer. BHA induced the mRNA and protein expression of CBR1 in hepatoma HepG2 cells. In a luciferase reporter gene assay, the promoter region between -2062 bp and the transcription start site of CBR1 was also activated by BHA. The transcription factor Nrf2 is known to be activated by BHA. There are 2 anti-oxidant responsive elements (ARE) that are bound by Nrf2 in this region. Mutation analyses revealed that one of the AREs participates in the gene regulation of CBR1 by Nrf2. Electrophoretic mobility shift assay revealed that Nrf2 binds the site. Moreover, to determine whether the functional ARE of CBR1 is conserved with the promoter region of homologues in other species, the nucleotide sequences of the functional AREs of the Chcr1 and Chcr2 genes, which are the Chinese hamster homologues of CBR1, were determined. The region has 2 AREs, and these genes were also induced by the forced expression of Nrf2 (cotransfection of pNrf2) in the luciferase reporter gene assay. In conclusion, Nrf2 is a novel transcriptional regulator of CBR1 genes in humans and the Chinese hamster. Because the regulation of CBR1 appears to be important for diseases, the induction of CBR1 by Nrf2 may be a therapeutic target.

Magnetic resonance (MR) differential diagnosis of breast tumors using apparent diffusion coefficient (ADC) on 1.5-T.

To review the published reports concerning the apparent diffusion coefficient (ADC) value evaluation for the differentiation between malignant and benign breast tumors, articles were searched with the inclusion criteria: (a) a 1.5-T unit was used; (b) the diagnostic criteria were clearly stated; (c) diffusion-weighted images (DWIs) were obtained, and ADC value was calculated; (d) ADC values of breast tumors were reported with mean +/- standard deviation (SD). Meta-analysis from 12 articles revealed that the pooled sensitivity and specificity were 0.89 (95% confidence interval [CI], 0.85-0.91) and 0.77 (95% CI, 0.69-0.84), respectively, and that only the maximum b factor correlated with the mean ADC values of malignant and benign tumors, and the noncancerous breast tissue (P< 0.05,P < 0.01,P< 0.05, respectively). In conclusion, ADC evaluation is useful for the differentiation between malignant and benign breast tumors.

Diagnostic utility of diffusion-weighted MR imaging and apparent diffusion coefficient value for the diagnosis of adrenal tumors.

PURPOSE: To determine the utility of diffusion-weighted MR imaging (DWI) for the diagnosis of adrenal tumors. MATERIALS AND METHODS: Forty-two patients (24 men and 18 women; age, 61.5 +/- 12.7 years old; range, 34-86 years) with 43 adrenal tumors (11 functioning cortical adenomas, 20 nonfunctioning cortical adenomas, 7 metastatic tumors, and 5 pheochromocytomas) were retrospectively investigated. DWIs were obtained by single-shot spin-echo type echo-planar imaging sequence (1.5 Tesla [T]; TR = 8000 ms, TE = 72, b-factor = 0 and 1000 s/mm(2)), and apparent diffusion coefficient (ADC) value was calculated. Chemical shift images were obtained by gradient echo sequence (TR = 161, TE = 2.38 [out-of-phase, OP] and 4.76 [in-phase, IP], FA = 60), and the signal intensity index (SII; [IP-OP]/IP *100%) was calculated. RESULTS: There was no difference in ADC values between adenomas (1.09 +/- 0.29*10(-3) mm(2)/s; range, 0.52-1.64) and metastatic tumors (0.85 +/- 0.26*10(-3); 0.51-1.23; p = 0.14). Pheochromocytomas showed the higher mean ADC value (1.59 +/- 0.34*10(-3); 1.04-1.96) compared with those of adenomas or metastatic tumors (P < 0.05 and P < 0.005, respectively). The mean SII of adenomas (62.1 +/- 17.9%; 14.5-88.4) was significantly higher than those of pheochromocytomas (4.0 +/- 10.0%; -19.6-3.3; P < 0.005) or metastatic tumors (-1.5 +/- 11.7%; -18.3-8.2; P < 0.01). There was no correlation between ADC values and SII. CONCLUSION: Although pheochromocytomas showed higher ADC values, we did not find that ADC value had diagnostic utility for differentiating adenomas and metastatic tumors.

Normal cranial nerves in the cavernous sinuses: contrast-enhanced three-dimensional constructive interference in the steady state MR imaging.

BACKGROUND AND PURPOSE: Three-dimensional (3D) constructive interference in steady state (CISS) MR imaging is useful for demonstrating cranial nerves (CNs) in the cistern. The purpose of this study was to evaluate normal CNs III, IV, V1, V2, and VI in the cavernous sinuses by using contrast-enhanced, three-dimensional (3D), Fourier transformation CISS MR imaging. METHODS: In 76 normal cavernous sinuses from 38 patients, detectability of CNs III-VI in the bilateral cavernous sinuses was evaluated by using contrast-enhanced 3D CISS MR imaging. In 40 cavernous sinuses from 20 patients, contrast-enhanced 3D CISS and contrast-enhanced T1-weighted MR imaging were compared for the detectability of these CNs. RESULTS: Each CN was separately demonstrated, and in 11 patients (29%), all CNs in the cavernous sinuses were identified on contrast-enhanced 3D CISS MR imaging. The images depicted the intracavernous segments of CNs III, IV, V1, V2, and VI in 76 (100%), 46 (61%), 70 (92%), 67 (88%), and 73 (96%) of the 76 sinuses, respectively. In comparison of imaging techniques, contrast-enhanced 3D CISS MR imaging had a detection rate significantly higher than that of enhanced T1-weighting imaging (P < .05) in all CNs except for CN III, which was detected in 100% of cases with both techniques. CONCLUSION: Contrast-enhanced 3D CISS MR imaging provides clear images of each CN in the cavernous segment. This useful method may contribute to the diagnosis of diseases involving the cavernous sinuses, such as Tolosa-Hunt syndrome.

Serous surface papillary carcinoma of the peritoneum: clinical, radiologic, and pathologic findings in 11 patients.

OBJECTIVE: The purpose of our study was to describe the clinical, radiologic, and pathologic findings of serous surface papillary carcinoma of the peritoneum in 11 patients. CONCLUSION: Serous surface papillary carcinoma of the peritoneum should be included in the differential diagnosis when ascites, omental caking, and peritoneal nodules or enhancement are observed in a postmenopausal woman with or without ovarian enlargement.

The combination of multi-voxel MR spectroscopy with MR imaging improve the diagnostic accuracy for localization of prostate cancer.

BACKGROUND: We assessed the usefulness of combined multi-voxel magnetic resonance spectroscopy (MRS) and MR imaging (MRI) in the diagnosis of prostate cancer localization. PATIENTS AND METHODS: MRS and MRI were performed in 21 patients with prostate cancer. On T2-weighted images, tumor localization was based on low signal intensity in the peripheral zone. At MRS, cancer patterns were diagnosed when the ratio of choline plus creatine to citrate was greater than 0.86. The results were analyzed with reference to pathological confirmation of prostate cancer at bilateral or unilateral lobe. RESULTS: Six out of 11 patients with unilateral positive biopsy specimens were diagnosed as unilateral cancer, and 9 of 10 patients with bilateral positive biopsy specimens were diagnosed as bilateral cancer on MRI. Two of 4 patients with unilateral cancer, who were not detected on MRI alone, were diagnosed as unilateral cancer on combined MRI and MRS. The accuracy of MRI alone was 71.4%, while that of combined MRI and MRS was 81.0%. CONCLUSION: Combined MRI and MRS improved the diagnostic accuracy for localization of prostate cancer.