In songbirds, aromatase (estrogen synthase) activity and mRNA are readily detectable in the brain. This neural aromatization presumably provides estrogen to steroid-sensitive targets via autocrine, paracrine, and synaptic mechanisms. The location of immunoreactive protein, however, has been difficult to describe completely, particularly in distal dendrites, axons, and terminals of the forebrain. Here we describe the neuroanatomical distribution of aromatase in the zebra finch by using a novel antibody raised specifically against zebra finch aromatase. The distribution of aromatase-positive somata in the zebra finch brain is in excellent agreement with previous reports. Additionally, this antibody reveals elaborate, spinous dendritic arbors, fine-beaded axons, and punctate terminals of telencephalic neurons that may synthesize estrogen. Some of these axon-like fibers extend into the high vocal center (HVC) and the robust nucleus of the archistriatum (RA) in males and females, suggesting a role for presynaptic aromatization in cellular processes within these loci. Adult males have more aromatase-positive fibers in the caudomedial neostriatum (NCM) and the preoptic area (POA) compared to females, despite the lack of detectable sex differences in the number of immunoreactive somata at these loci. Thus, the compartmentalization of aromatase in dendrites and axons may serve a sexually dimorphic function in the songbird. Finally, in adult males, aromatase expression is down-regulated by circulating estradiol in the hippocampus, but not in the NCM or POA. The distribution of aromatase suggests a role for aromatization in the regulation of pre- and postsynaptic function in steroid sensitive areas of the songbird forebrain.

The interaction between the hormone hepcidin and the iron exporter ferroportin (Fpn) regulates plasma iron concentrations. Hepcidin binds to Fpn and induces its internalization and degradation, resulting in decreased iron efflux from cells into plasma. Fpn mutations in N144, Y64N, and C326 residue cause autosomal dominant disease with parenchymal iron overload, apparently due to the resistance of mutant Fpn to hepcidin-mediated internalization. To define the mechanism of resistance, we generated human Fpn constructs bearing the pathogenic mutations. The mutants localized to the cell surface and exported iron normally, but were partially or completely resistant to hepcidinmediated internalization and continued to export iron despite the presence of hepcidin. The primary defect with exofacial C326 substitutions was the loss of hepcidin binding, which resulted in the most severe phenotype. The thiol form of C326 was essential for interaction with hepcidin, suggesting that C326-SH homology is located in or near the binding site of hepcidin. In contrast, N144 and Y64 residues were not required for hepcidin binding, but their mutations impaired the subsequent internalization of the ligandreceptor complex. Our observations explain why the mutations in C326 Fpn residue produce a severe form of hemochromatosis with iron overload at an early age. (Blood. 2009;114:437-443) IntroductionHereditary hemochromatosis is a disease characterized by high transferrin saturation and parenchymal iron overload. Most forms are caused by autosomal-recessive mutations in HFE, transferrin receptor 2, hemojuvelin, or hepcidin. These mutations lead to deficiency of the iron-regulatory hormone hepcidin. Rarely, hereditary hemochromatosis is caused by autosomal-dominant mutations in the hepcidin receptor ferroportin (Fpn). 1 Fpn is the only known cellular iron exporter in vertebrates and is expressed on all tissues that handle major iron flows, including absorptive enterocytes, iron-recycling macrophages, and iron-storing hepatocytes. 2 The rate of iron efflux from these cells is a major determinant of iron concentration in plasma and is directly proportional to the number of Fpn molecules on the cell surface. Furthermore, by controlling the absorption of dietary iron, Fpn expression on the basolateral membranes of enterocytes ultimately determines total body iron. The concentration of cell surface Fpn is regulated mainly by the interaction with its ligand hepcidin. Hepcidin binding to Fpn results in internalization and degradation of the ligand-receptor complex and leads to decreased iron efflux from cells into plasma. 3 The hepcidin-Fpn interaction is critical for normal iron homeostasis and underlies the pathogenesis of iron disorders, including not only hereditary hemochromatosis, but also anemia of inflammation and iron-loading anemias. 4 Although the complete loss of Fpn is embryonic lethal in zebrafish and mice, 2,5 some heterozygous missense mutations in the Fpn gene result in an autosomal-dominant form of iron overload disease called ...

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Patients lacking functional adenosine deaminase activity suffer from severe combined immunodeficiency (ADA SCID), which can be treated with ADA enzyme replacement therapy (ERT), allogeneic hematopoietic stem cell transplantation (HSCT), or autologous HSCT with gene-corrected cells (gene therapy-GT). A cohort of 10 ADA SCID patients, aged 3 months to 15 years, underwent GT in a Phase II clinical trial between 2009 and 2012. Autologous bone marrow CD34+ cells were transduced ex vivo with the MND-ADA gamma-retroviral vector (gRV) and infused following busulfan reduced intensity conditioning. These patients were monitored in a long-term follow-up protocol over 8-11 years. Nine of ten patients have sufficient immune reconstitution to protect against serious infections, and have not needed to resume ERT or proceed to secondary allogeneic HSCT. ERT was restarted 6 months after GT in the oldest patient who had no evidence of benefit from GT. Four of nine evaluable patients with the highest gene marking and B cell numbers remain off immunoglobulin replacement therapy and responded to vaccines. There were broad ranges of responses in normalization of ADA enzyme activity and adenine metabolites in blood cells, and levels of cellular and humoral immune reconstitution. Outcomes were generally better in younger patients and those receiving higher doses of gene-marked CD34+ cells. No patient experienced a leukoproliferative event after GT, despite persisting prominent clones with vector integrations adjacent to proto-oncogenes. These long-term findings demonstrate enduring efficacy of GT for ADA SCID, but risks of genotoxicity with gRVs. (Clinicaltrials.gov #NCT00794508)

Protease inhibitors (PIs), particularly the soybean-derived Bowman-Birk inhibitor, have proved to be powerful blockers of carcinogenesis in many in vitro and animal model systems. However, so far an ability of PIs to suppress gastric carcinogenesis has not been demonstrated, because of the anticipated 'hostile' acidic gastric environment for the PI to exert its action. We therefore examined the ability of a purified PI from the Indian legume the field bean (FBPI), when administered by gavage, to subdue benzopyrene (BP)-induced neoplasia of the forestomach of mice. Forestomach tumors were produced in female Swiss albino mice by oral administration of BP at a dose of 1 mg twice weekly for 4 weeks. Groups of mice were treated per os with an aqueous solution of FBPI for 3 months or more at a dose of 20 mg/kg once daily, six times a week, either from the initiation of carcinogenesis or after completion of the carcinogen treatment. Another group was treated likewise with autoclaved inactive FBPI. Mice of both the FBPI-treated groups showed statistically significant (P < 0.001) reductions in the multiplicity of gastric tumors, with the tumor incidence being unaffected. However, the suppression of tumor multiplicity was appreciably (P < 0.01) more in the group that received FBPI treatment concomitantly with the carcinogen. The mice that were treated with heat-inactivated FBPI showed similar tumor multiplicity to the BP-treated group, indicating that the oncopreventive activity of FBPI is related to its protease inhibitory capacity. These observations point to the potential of PIs as effective chemoprotectors against gastric cancer in animals and, possibly, in humans as well.