Sidney Y Ren

Learn More
Metabolic syndrome is a constellation of multiple metabolic risk factors including abdominal obesity, glucose intolerance, insulin resistance, dyslipidemia and hypertension. Over the past decades, the prevalence of metabolic syndrome has increased dramatically, imposing a devastating, pandemic health threat. More importantly, individuals with metabolic(More)
Hypercalcemia in human granuloma-forming diseases like sarcoidosis results from the endogenous overproduction of 1,25-dihydroxyvitamin D [1,25-(OH)2D] by disease-activated tissue macrophages. The recent identification of an immortalized chick myelomonocytic cell line, HD-11, that constitutively expresses a 25-hydroxyvitamin D (25-OHD) 1-hydroxylation(More)
We undertook an investigation of an outbreak of rachitic bone disease in the Emperor Tamarin New World primate colony at the Los Angeles Zoo in the mid-1980s. The disease phenotype resembled that observed in humans with an inactivating mutation of the vitamin D receptor (VDR), hypocalcemia, high 1,25-dihydroxyvitamin D (1,25-(OH)(2)D) levels, and rickets in(More)
To better understand the extrarenal production of active vitamin D metabolites by cells of the monocyte/macrophage lineage, we investigated the 25-hydroxyvitamin D (25OHD)-1-hydroxylation reaction in the v-myc-transformed chick myelomonocytic cell line HD-11; the 1-hydroxylation reaction in this cell line has a high affinity for 25-hydroxylated vitamin D(More)
Tissue macrophages from patients with granuloma-forming disease, most notably sarcoidosis, express a 25-hydroxyvitamin D-1-hydroxylase which can produce in vivo sufficient quantities of the active vitamin D metabolite 1,25-dihydroxyvitamin D to cause hypercalcemia. In contrast to the NADPH-dependent cytochrome P450-linked mixed function oxidase which is(More)
We have recently described the existence of a cytochrome P450-associated, mitochondrial-based 25-hydroxyvitamin D (25-OHD)-1-hydroxylation reaction in the chick macrophage-like cell line HD-11. Considering that this reaction is regulated by the same set of factors (ie. interferon-gamma, lipopolysaccharide, and glucocorticoids) that modulate expression of(More)
SCOPE The objective of this study was to evaluate the effect of fenugreek furostanolic saponins (Fenfuro(TM) ) either alone or in combination with chlorogenic acid (GCB-70(TM) ) on insulin resistance in mice. METHODS AND RESULTS Male C57BL/6J mice were subjected to a normal or high-fat diet (HFD) and were randomly assigned to receive Fenfuro(TM) ,(More)
BACKGROUND Adiponectin (APN), an adipose-derived adipokine, alleviates lipopolysaccharide (LPS)-induced injury in multiple organs including hearts although the underlying mechanism in endotoxemia remains elusive. This study was designed to examine the role of adiponectin in LPS-induced cardiac anomalies and inflammation as well as the underlying mechanism(More)
Cells of the monocyte/macrophage lineage are capable of both nitric oxide (NO) and 1,25-dihydroxyvitamin D [1, 25-(OH)2D] production through expression of inducible nitric oxide synthase (iNOS) and a putative 25-hydroxyvitamin D (25-OHD)-1-hydroxylase, respectively. We have recently reported that 1,25-(OH)2D synthesis in the chick myelomonocytic cell line(More)
  • 1