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Zeina Moutih Allah Soayfane

Assistant professor
Life & Earth Sciences department - Section I - Hadath
Speciality: Biology
Specific Speciality: Pharmacologie - Toxicologie

Positions
2012 - present : Doctor

Lebanese university
Beirut

2011 - 2012 : Postdoctoral Fellow

State University of New York
New York - USA

Teaching 8 Taught Courses
(2014-2015) BEMA 514 - Marine products of biological, chemical and ecological interest

M2 Marine Biology and Ecology

(2014-2015) Biol 100 - Cellular Biology and General Histology (animal and plant)

BS Earth and life sciences

(2014-2015) Biol 111 - Organisation of the living world animal, Reproduction, and Embryology

BS Earth and life sciences

(2014-2015) Biol 113 - Genetics, human anatomiy and plant reproduction

BS Earth and life sciences

(2014-2015) BioV 401 - Mycology Lab

M1 Environmental and life Sciences - Option : Vegetal

(2014-2015) Biol 240 - Cell Biology Lab (Histology, Embryology, Reproduction, and genetics)

BS Earth and life sciences

(2014-2015) Biol 242 - Organs Histology Lab

BS Earth and life sciences

(2014-2015) Biol 247 - Zoology II (vertebrates) Lab

BS Earth and life sciences

Education
Publications 2 publications
Respective contributions of intestinal Niemann-Pick C1-like 1 and scavenger receptor class B type I to cholesterol and tocopherol uptake: in vivo v. in vitro studies. Br J Nutr. 2012

The intestinal absorption of cholesterol and lipid micronutrients such as vitamin E has been shown to share some common pathways. The present study aims to further compare the uptake of cholesterol ([3H]cholesterol v. 22-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-23,24-bisnor-5-cholen-3-ol (NBD-cholesterol)) and tocopherol in Caco-2 TC-7 cells and in mouse intestine, with special focus on the respective roles of scavenger receptor class B type I (SR-BI) and Niemann-Pick C1-like 1 (NPC1L1). Conversely to NBD-cholesterol, the uptakes of [3H]cholesterol and tocopherol by Caco-2 cells were impaired by both block lipid transport-1 and ezetimibe, which inhibit SR-BI and NPC1L1, respectively. These inhibitions occurred only when cholesterol or tocopherol was delivered to cells included in micelles that contained biliary acid and at least oleic acid as a lipid. In vivo, after 2 h of digestion in mice, the uptake of the two cholesterol analogues and of tocopherol all showed distinct patterns along the duodenum-jejunum axis. [3H]Cholesterol uptake, which correlated closely to NPC1L1 mRNA expression in wild-type (wt) mice, was strongly inhibited by ezetimibe. Intestinal SR-BI overexpression did not change NPC1L1 expression and led to a significant increase in [3H]cholesterol uptake in the distal jejunum. Conversely, neither ezetimibe treatment nor SR-BI overexpression had an effect on NBD-cholesterol uptake. However, in contrast with SR-BI mRNA expression, tocopherol absorption increased strongly up to the distal jejunum in wt mice where it was specifically inhibited by ezetimibe, and was increased in the proximal intestine of intestinal SR-BI-overexpressing mice. Thus, cholesterol and tocopherol uptakes share common pathways in cell culture models, but display different in vivo absorption patterns associated with distinct contributions of SR-BI and NPC1L1.

P-glycoprotein dysfunction contributes to hepatic steatosis and obesity in mice PLoS One 2011

Although the main role of P-glycoprotein (Pgp) is to extrude a broad range of xenochemicals and to protect the organism against xenotoxicity, it also transports a large range of endogenous lipids. Using mice lacking Pgp, we have investigated the possible involvement of Pgp in lipid homeostasis in vivo. In a long term study, we have followed the food intake, body status and lipid markers in plasma and liver of wild-type and mdr1ab(-/-) mice over 35 weeks. Pgp-deficient mice showed excess weight, hypertrophy of adipose mass, high insulin and glucose levels in plasma. Some of these metabolic disruptions appeared earlier in Pgp-deficient mice fed high-fat diet. Moreover, hepatosteatosis with increased expression of genes involved in liver detoxification and in de novo lipid synthesis occurred in Pgp-deficient mice. Overall, Pgp deficiency clearly induced obesity in FVB genetic background, which is known to be resistant to diet-induced obesity. These data reinforce the finding that Pgp gene could be a contributing factor and possibly a relevant marker for lipid disorder and obesity. Subsequent to Pgp deficiency, changes in body availabilities of lipids or any Pgp substrates may affect metabolic pathways that favour the occurrence of obesity. This is of special concern because people are often facing simultaneous exposition to many xenochemicals, which inhibits Pgp, and an excess in lipid dietary intake that may contribute to the high prevalence of obesity in our occidental societies.

Languages
English

Full professional proficiency

French

Full professional proficiency