Biologists have long used model organisms to study human diseases, particularly when the model bears a close resemblance to the disease. We present a method that quantitatively and systematically identifies nonobvious equivalences between mutant phenotypes in different species, based on overlapping sets of orthologous genes from human, mouse, yeast, worm, and plant (212,542 gene-phenotype associations). These orthologous phenotypes, or phenologs, predict unique genes associated with diseases. Our method suggests a yeast model for angiogenesis defects, a worm model for breast cancer, mouse models of autism, and a plant model for the neural crest defects associated with Waardenburg syndrome, among others. Using these models, we show that SOX13 regulates angiogenesis, and that SEC23IP is a likely Waardenburg gene. Phenologs reveal functionally coherent, evolutionarily conserved gene networks-many predating the plant-animal divergence-capable of identifying candidate disease genes.angiogenesis | bioinformatics | evolution | gene-phenotype associations | homology B iochemical and molecular functions of a given protein are generally conserved between organisms; this observation is fundamental to biological research. For example, in x-ray crystallography studies, one can often choose the organism from which the protein is most easily crystallized to facilitate the study of the protein's biochemical function. On the other hand, even with a conserved gene, disruption of function may give rise to radically different phenotypic outcomes in different species. For example, mutating the human RB1 gene leads to retinoblastoma, a cancer of the retina, yet disrupting the nematode ortholog contributes to ectopic vulvae (1, 2). Thus, although a gene's "molecular" functions are conserved, the "organism-level" functions need not be. When a conserved gene is mutated, the resulting organism-level phenotype is an emergent property of the system. This bedrock principle underlying the use of model organisms not only allows us to study important aspects of human biology using mice or frogs, but also permits exploration of inherently multicellular processes, such as cancer, using unicellular organisms like yeast.Within this paradigm, once a molecular function has been discovered in one organism, it should be predictable in other organisms: GSK3 homologs in yeast are kinases, and such GSK3 homologs in every other organism will generally be kinases. In contrast, the emergent organism-level phenotypes are far less predictable between organisms, in part because relationships between genes and phenotypes are many-to-many. Manipulation of GSK3 perturbs nutrient and stress signaling in yeast, anteroposterior patterning and segmentation in insects, dorsoventral patterning in frogs, and craniofacial morphogenesis in mice (3-5). Recognizing functionally equivalent organism-level phenotypes between model organisms can therefore be nonobvious, especially across large evolutionary distances.However, the ability to recognize equivalent phenotypes betwee...

The pharmacokinetics of oleanolic acid was evaluated in vitro and in vivo. From Caco-2 cell permeation studies, oleanolic acid was a low permeability compound with no directional effects, suggesting a low in vivo absorption mediated by a passive diffusion. Oleanolic acid was metabolically unstable following incubation with rat liver microsomes in the presence of NADPH. After intravenous injection at doses of 0.5, 1 and 2 mg/kg doses, oleanolic acid showed dose-linear pharmacokinetics as evidenced by unaltered CL (28.6-33.0 ml/min/kg), Vss (437-583 ml/kg), dose-normalized AUC (16.0-17.9 microg min/ml based on 1 mg/kg) and t1/2 (41.9-52.7 min). Following oral administration of oleanolic acid at doses of 10, 25 and 50 mg/kg, Tmax, t1/2, dose-normalized Cmax (66-74 ng/ml based on 25 mg/kg) and dose-normalized AUC (5.4-5.9 microg min/ml based on 25 mg/kg) were comparable between 25 and 50 mg/kg dose, but the plasma concentrations at 10 mg/kg dose were not measurable as they were below the limit of quantitation (2 ng/ml). The absolute oral bioavailability was 0.7% for oral doses of 25 and 50 mg/kg. The extent of urinary excretion was minimal for both i.v. and oral doses. The very low oral bioavailability of oleanolic acid could be due to a poor absorption and extensive metabolic clearance.

Severe ascites is a hallmark of advanced ovarian cancer (OVCA), yet the underlying mechanism that creates an imbalance between peritoneal vascular leakage and lymphatic drainage is unknown. Here, we identified and characterized peritoneal lymphatic vessels in OVCA mice, a model generated by implantation of human OVCA cells into athymic nude mice. The OVCA mice displayed substantial lymphangiogenesis and lymphatic remodeling, massive infiltration of CD11b + /LYVE-1 + macrophages and disseminated carcinomatosis in the mesentery and diaphragm, and progressive chylous ascites formation. Functional assays indicated that the abnormally abundant lymphatic vessels in the diaphragm were not conductive in peritoneal fluid drainage. Moreover, lipid absorbed from the gut leaked out from the aberrant mesenteric lymphatic vessels. Our results indicate that

The absorption, dose-linearity and pharmacokinetics of compound K, a major intestinal bacterial metabolite of ginsenosides, were evaluated in vitro and in vivo. Using the Caco-2 cell monolayers, compound K showed moderate permeability with no directional effects, thus suggesting passive diffusion. After intravenous dose (i.v.; 1, 2, and 10 mg/kg), no significant dose-dependency was found in Cl (17.3-31.3 ml/min/kg), Vss (1677-2744 ml/kg), dose-normalized AUC (41.8-57.8 microg.min/ml based on 1 mg/kg) and t1/2. The extent of urinary excretion was minimal for both i.v. and oral doses. The extent of compound K recovered from the entire gastrointestinal tract at 24h were 24.4%-26.2% for i.v. doses and 54.3%-81.7% for oral doses. Following oral administration (doses 5-20 mg/kg), dose-normalized AUC (based on 5 mg/kg) was increased at the 20 mg/kg dose (85.3 microg.min/ml) compared with those at lower doses (4.50-10.5 microg.min/ml). Subsequently, the absolute oral bioavailability (F) was increased from 1.8%-4.3% at the lower doses to 35.0% at the 20 mg/kg dose. The increased F could be related to the saturation of carrier-mediated hepatic uptake and esterification of compound K with fatty acids in the liver.

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