Isolation of a novel leptin receptor gene promoter preferentially functioning in neuronal cells.

Leptin exerts its metabolic effects by binding to the leptin receptor (Ob-R). In humans, the promoter of the Ob-R gene-related protein (Ob-RGRP) gene and the B219/Ob-R promoter have been speculated to spatially and temporarily regulate Ob-R gene transcription; however, the promoter function of the Ob-R gene has not been directly analyzed. Using 5' rapid amplification of the cDNA end, we isolated novel ob-r transcripts starting from the 3' portions of the B219/ob-r 5'-untranslated region in the adult mouse brain. The proximal promoter containing these start sites showed robust activity in neuron-derived, but not non-neuronal cell lines. The promoter activity was comparable with that of the ob-rgrp promoter in a neuronal cell, but significantly weaker in non-neuronal cells. Deletion analyses identifying two enhancer elements were located in this promoter. The identification of a novel ob-r gene promoter might provide a useful tool to study neuron specific expression and hormonal regulation of the ob-r gene.

Hereditary hemorrhagic telangiectasia with multiple hepatic and pulmonary nodular lesions.

A 50-year-old female visited the hospital for further evaluation of multiple pulmonary and hepatic nodules. First, she visited her primary physician for general fatigue due to anemia. She had recurrent epistaxis, and her mother had suffered from hereditary hemorrhagic telangiectasia (HHT). Telangiectasias were present in the stomach. This patient was diagnosed with HHT. Computed tomography (CT) revealed multiple pulmonary and hepatic nodules. The pulmonary nodules were due to bleeding from arteriovenous malformations of the lung. Abdominal CT and angiography showed a dilated and meandering hepatic artery, arteriovenous shunts and multiple hepatic nodules. Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) showed enhancement in the early dynamic phase and in the liver-specific phase. A liver tumor biopsy of a hepatic nodule showed nodular regenerative hyperplasia (NRH). This report presents a case of HHT with multiple pulmonary and hepatic nodular lesions. Gd-EOB-DTPA-enhanced MRI was useful for making a diagnosis of NRH.