 Barbara
Stoll, Ph.D.
M.S. Chemistry, Albert-Ludwigs-Universitaet, Freiburg,
Germany, 1987.
Ph.D. Biochemistry, Albert-Ludwigs-Universitaet, Freiburg,
Germany, 1993.
Postdoctoral Fellowship, Pediatric Nutrition, USDA-ARS
Children’s Nutrition Research Center Department
of Pediatrics, 1994-1996.
Research Associate, USDA-ARS Children’s Nutrition
Research Center, 1996-Present.
The emphasis of my Ph.D. thesis was on hepatic glutamine/glutamate uptake using isolated perfused rat liver and isolated hepatocytes. Specifically, we were interested in a)
periportal and perivenous hepatocyte heterogeneity regarding the uptake of amino acids and intermediates and b) the role of changes of cell volume in hepatocyte metabolism.
After my Ph.D., I became interested in the gut, in particular the small intestine of infant pigs that provides an excellent model for the human infant. I came to the CNRC for a
postdoctoral fellowship working with Peter Reeds. The focus of my project was on the study of small intestinal fuel metabolism in infant pigs. Using stable isotopes and arteriovenous
organ balance techniques in normally fed animals, we found that the gut mucosa utilizes large quantities of amino acids for protein synthesis and energy requirements, including essential amino acids.
Following my postdoctoral fellowship I joined Doug Burrin’s lab. We want to find out how luminal nutrients mediate the effects that lead to normal growth and function of the small intestine.
(See Doug Burrin and Postdoc links). Our current studies are aimed at investigating the small intestinal metabolic fate of amino acids and glucose in piglets maintained by total parenteral nutrition
(TPN), which is a condition where gut growth is greatly compromised. Some of my responsibilities in the lab include, coordinating and performing all surgical procedures, training postdocs, planning
and overseeing experiments, and stable isotope analysis by mass spectrometry.
Grants
2007: Maurice Shils Grant, A.S.P.E.N. Rhoads Research Foundation, American Society for Parenteral and Enteral Nutrition, Insulin Resistance and Gluconeogenesis in TPN-Fed Piglets. Parenteral Nutrition and Hepatic Insulin Resistance in Neonatal Pigs.
2006: CNRC Bristol-Myers Squib: Impact of intestinal microflora and probiotics on host amino acid availability.
Representative Publications
Riedijk MA, Stoll B, Chacko S, Schierbeek H, Sunehag AL, van Goudoever JB, Burrin DG. Methionine transmethylation and transsulfuration in the piglet gastrointestinal tract. Proc Natl Acad Sci U S A (2007) 104:3408-3413.
Lambert BD, Filip R, Stoll B, Junghans P, Derno M, Hennig U, Souffrant WB, Pierzynowski S, Burrin DG. First-pass metabolism limits the intestinal absorption of enteral alpha-ketoglutarate in young pigs. J Nutr (2006) 136:2779-2784.
Wang H, Khaoustov VI, Krishnan B, Stoll B, Burrin DG, Yoffe B. Total parenteral nutrition induces liver steatosis and apoptosis in newborn piglets. J Nutr (2006) 136:2547-2552.
Stoll B, Burrin DG. Measuring splanchnic amino acid metabolism in vivo using stable isotope tracers. J Anim Sci (2006) 84(E. Suppl.):E60-E72.
Stoll B, Price PT, Reeds PJ, Chang X, Henry JF, van Goudoever JB, Holst JJ, Burrin DG. Feeding an elemental versus a milk-based formula does not decrease intestinal mucosal growth in infant pigs. JPEN J Parenter Enteral Nutr (2006) 30:32-29.
Stephens J, Stoll B, Cottrell J, Chang X, Helmrath M, Burrin DG. Glucagon-like peptide-2 acutely increases proximal small intestinal blood flow in TPN-fed neonatal piglets. Physiol Regul Integr Comp Physiol (2006) 59:R283-R289.
Shoveller AK, Stoll B, Ball RO, Burrin DG. Nutritional and functional importance of intestinal sulfur amino acid metabolism. J Nutr (2005) 135:1609-1612.
Schaart MW, Schierbeek H, van der Schoor SR, Stoll B, Burrin DG, Reeds PJ, van Goudoever JB. Threonine utilization is high in the intestine of piglets. J Nutr (2005) 135:765-770.
Niinikoski H, Stoll B, Guan X, Kansagra K, Lambert B, Stephens J, Hartmann B, Holst JJ, Burrin DG. Onset of small intestinal atrophy is associated with reduced intestinal blood flow in TPN-fed neonatal piglets. J Nutr (2004) 134:1467-1474.
Burrin DG, Stoll B, Guan X, Sangild PT, and Petersen YM. GLP-2: a key link between nutrition and intestinal adaptation. J Nutr (2003) 133:3712-3716.
Bos C, Stoll B, Fouillet H, Gaudichon C, Guan X, Grusak MA, Reeds PJ, Tomé D, Burrin DG. Intestinal lysine metabolism is driven by the enteral availability of dietary lysine in piglets fed a bolus meal. Am J Physiol (2003) 285:E1246-E1257.
Burrin DG, Stoll B, Guan X. Glucagon-like peptide 2 function in domestic animals. Domest Anim Endocrinol (2003) 23:103-122.
Van der Schoor SRD, Reeds PJ, Stoll B, Henry JF, Rosenberger JR, Burrin DG, van Goudoever JB. The high metabolic costs of a functional gut. Gastroenterology (2002) 123:1931-1940.
Burrin DG and Stoll B. Key nutrients and growth factors for the neonatal gastrointestinal tract. Clin Perinatol. (2002) 29:65-96.
Reeds PJ, Burrin DG, Davis TA, Fiorotto ML, Stoll B, Van Goudoever JB. Protein Nutrition of the Neonate. Proc Nutr Soc (2000) 59: 87-97.
Stoll B, Chang X, Fan MZ, Reeds PJ, Burrin DG. Enteral nutrient intake determines the rate of intestinal protein synthesis and accretion in neonatal pigs. Am J Physiol (2000) 279:G288-G294.
Burrin DG, Stoll B, Jiang R, Chang X, Hartmann B, Holst JJ, Greeley GH Jr, Reeds PJ. Minimal enteral nutrient requirements for intestinal growth in neonatal piglets: How much is enough? Am J Clin Nutr (2000) 71: 1603-1610.
Stoll B, Burrin DG, Henry J, Yu H, Jahoor F, Reeds PJ. Substrate oxidation by the portal drained viscera of fed piglets. Am J Physiol (1999) 277: E168-E175.
Stoll B, Burrin DG, Henry JF, Jahoor F, Reeds PJ. Dietary and systemic phenylalanine utilization for mucosal and hepatic constitutive protein synthesis in pigs. Am J Physiol (1999) 276: G49-G57.
Stoll B, Henry J, Reeds PJ, Yu H, Jahoor F, Burrin DG. Catabolism dominates the first-pass intestinal metabolism of dietary essential amino acids in milk protein-fed piglets. J Nutr (1998) 128: 606-614.
Stoll B, Burrin DG, Henry J, Jahoor F, Reeds PJ. Phenylalanine utilization by the gut and liver measured with intravenous and intragastric tracers in pigs. Am J Physiol (1997) 273: G1208-G1217.
vom Dahl S, Stoll B, Gerok W, Häussinger D. Inhibition of proteolysis by cell swelling in the liver requires intact microtubular structures. Biochem J (1995) 308: 529-536.
Stoll B, Gerok W, Lang F, Häussinger D. Liver cell volume and protein synthesis. Biochem J (1992) 287: 217-222.
Stoll B, McNelly S, Buscher HP, Häussinger D. Functional hepatocyte heterogeneity in glutamate, aspartate and alpha-ketoglutarate uptake: a histoautoradiographical study. Hepatology (1991) 13: 247-253.
Häussinger D, Stoll B, Stehle T, Gerok W. Hepatocyte heterogeneity in glutamate metabolism and bidirectional transport in perfused rat liver. Eu J Biochem (1989) 185: 189-195.
Stoll B, Häussinger D. Functional hepatocyte heterogeneity. Vascular 2-oxoglutarate is almost exclusively taken up by perivenous, glutamine-synthetase-containing hepatocytes. Eur J Biochem (1989) 181: 709-716.
 Xiaoyan
Chang
BS in Chemistry, Lanzhou University, Lanzhou, PR China,
1983
MS in Physical Chemistry, Lanzhou University, Lanzhou,
PR China, 1986
MS in Analytic Chemistry, California Polytechnic University,
LA, USA, 1995
I have worked in Doug Burrin’s lab since 1996.
Prior to that I worked in industrial laboratories for
four years. My main duties are to train and assist postdoctoral
fellows with routine techniques, such as histology,
protein and DNA assays. I assist with animal surgeries,
tracer infusion protocols and mass spectrometry analysis.
I also supervise and maintain lab equipment and handle
purchasing records for the lab. Other responsibilities
in the lab include helping to develop and testing new
methods. I am involved in several ongoing projects in
the lab.
 Liwei
Cui
BS in Microbiology, Nankai
University, Tianjin, China, 1988
MS in Molecular Biology,
Peking Union Medical College, Beijing, China, 1991
MS in Biochemistry, Iowa
State University, Ames, Iowa, 2001
I joined Doug Burrin’s
lab in 2003. My primary responsibility is quantitative
analysis of biological samples using different techniques.
I am involved in troubleshooting new techniques to
be implemented in the lab. I also supervise and assist
postdoctoral fellows and students in general lab operation,
quantitative analyses and surgical procedures.
 Xinfu
Guan, Ph.D.
B.Sc. (Biology), Central China Agricultural University,
Wuhan, 1984
Ph.D. (Nutrition), Michigan State University, East
Lansing, 2000
My research interest is to investigate hormonal
and nutritional regulation of amino acid transport
and protein metabolism using stable isotope methodology.
My Ph.D. thesis focused on the regulation of glucose
and protein metabolism in the porcine mammary gland
and established the physiological basis for indispensable
amino acids requirements for milk synthesis in lactating
swine. As a recipient of the British Sino Friendship
Fellowship, I studied at the University of Nottingham
focusing on nutritional and hormonal regulation of
hepatic insulin?like growth factor binding proteins.
I came to Doug Burrin’s lab in November 2000.
Currently, I am studying the acute actions of glucagon-like
peptide-2 on gut glucose and protein metabolism in
the total parenterally fed neonatal piglets. We have
found that this hormone acutely upregulates intestinal
blood flow, possibly via a nitric oxide-dependent mechanism,
and increases intestinal energy and protein anabolism
in parenterally fed neonates.
Publications:
Guan, X. F., B. Stoll, X. Lu, K. Tappenden, J.
J. Holst, B. Hartman, and D. Burrin. 2002. Glucagon-like
peptide-2 acutely increases intestinal blood flow and
substrate utilization in parenterally fed neonatal
pigs. Submitted to Gastroenterology.
Guan, X. F., B. J. Bequette, G. Calder, P. K. Ku,
K. N. Ames, and N. L. Trottier. 2002. Amino acid availability
affects their trans-membrane transport and protein
metabolism in the porcine mammary gland. J. Nutr. 132:1224-1234.
Guan, X. F., J. J. Matte, J. L. Snow, P. Ku, J.
Burton, and N. L. Trottier. 2000. High-chromium yeast
supplementation improves glucose tolerance by decreasing
hepatic extraction of insulin in pigs. J. Nutr. 130:1274-1279.
Trottier, N. L. and X. F. Guan. 2000. Research
paradigms behind amino acid requirements of the lactating
sow: Theory and applications. J. Anim. Sci. 78(Suppl.
3): 48-58. |
