1
|
Lee B, Diaz GA, Rhead W, Lichter-Konecki U, Feigenbaum A, Berry SA, Le Mons C, Bartley J, Longo N, Nagamani SC, Berquist W, Gallagher RC, Harding CO, McCandless SE, Smith W, Schulze A, Marino M, Rowell R, Coakley DF, Mokhtarani M, Scharschmidt BF. Glutamine and hyperammonemic crises in patients with urea cycle disorders. Mol Genet Metab 2016; 117:27-32. [PMID: 26586473 PMCID: PMC4915945 DOI: 10.1016/j.ymgme.2015.11.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/10/2015] [Accepted: 11/10/2015] [Indexed: 12/30/2022]
Abstract
UNLABELLED Blood ammonia and glutamine levels are used as biomarkers of control in patients with urea cycle disorders (UCDs). This study was undertaken to evaluate glutamine variability and utility as a predictor of hyperammonemic crises (HACs) in UCD patients. METHODS The relationships between glutamine and ammonia levels and the incidence and timing of HACs were evaluated in over 100 adult and pediatric UCD patients who participated in clinical trials of glycerol phenylbutyrate. RESULTS The median (range) intra-subject 24-hour coefficient of variation for glutamine was 15% (8-29%) as compared with 56% (28%-154%) for ammonia, and the correlation coefficient between glutamine and concurrent ammonia levels varied from 0.17 to 0.29. Patients with baseline (fasting) glutamine values >900 μmol/L had higher baseline ammonia levels (mean [SD]: 39.6 [26.2]μmol/L) than patients with baseline glutamine ≤ 900 μmol/L (26.6 [18.0]μmol/L). Glutamine values >900 μmol/L during the study were associated with an approximately 2-fold higher HAC risk (odds ratio [OR]=1.98; p=0.173). However, glutamine lost predictive significance (OR=1.47; p=0.439) when concomitant ammonia was taken into account, whereas the predictive value of baseline ammonia ≥ 1.0 upper limit of normal (ULN) was highly statistically significant (OR=4.96; p=0.013). There was no significant effect of glutamine >900 μmol/L on time to first HAC crisis (hazard ratio [HR]=1.14; p=0.813), but there was a significant effect of baseline ammonia ≥ 1.0 ULN (HR=4.62; p=0.0011). CONCLUSIONS The findings in this UCD population suggest that glutamine is a weaker predictor of HACs than ammonia and that the utility of the predictive value of glutamine will need to take into account concurrent ammonia levels.
Collapse
Affiliation(s)
- B Lee
- Baylor College of Medicine, Houston, TX, USA.
| | - G A Diaz
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - W Rhead
- The Medical College of Wisconsin, Milwaukee, WI, USA
| | | | | | - S A Berry
- Univ. of Minnesota, Minneapolis, MN, USA
| | - C Le Mons
- National Urea Cycle Disorders Foundation, Pasadena, CA, USA
| | - J Bartley
- Miller Children's Hospital, Long Beach, CA, USA
| | - N Longo
- Univ. of UT, Salt Lake City, UT, USA
| | | | | | | | | | - S E McCandless
- Case Western Reserve Univ. Medical Center, Cleveland, OH, USA
| | - W Smith
- Maine Medical Ctr., Portland, ME, USA
| | - A Schulze
- The Hospital for Sick Children, Univ. of Toronto, Canada
| | - M Marino
- Oregon Health Sciences, Portland, OR, USA
| | - R Rowell
- MED Technical Consulting, Inc., Union City, CA, USA
| | | | | | | |
Collapse
|
2
|
Bellur S, Jain M, Cuthbertson D, Krakow D, Shapiro JR, Steiner RD, Smith PA, Bober MB, Hart T, Krischer J, Mullins M, Byers PH, Pepin M, Durigova M, Glorieux FH, Rauch F, Sutton VR, Lee B, Nagamani SC. Cesarean delivery is not associated with decreased at-birth fracture rates in osteogenesis imperfecta. Genet Med 2015; 18:570-6. [PMID: 26426884 PMCID: PMC4818203 DOI: 10.1038/gim.2015.131] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 08/14/2015] [Indexed: 11/18/2022] Open
Abstract
Purpose Osteogenesis imperfecta (OI) predisposes to recurrent fractures. The moderate-to-severe forms of OI present with antenatal fractures and the mode of delivery that would be safest for the fetus is not known. Methods We conducted systematic analyses on the largest cohort of individuals (n=540) with OI enrolled to-date in the OI Linked Clinical Research Centers. Self-reported at-birth fracture rates were compared in individuals with OI types I, III, and IV. Multivariate analyses utilizing backward-elimination logistic regression model building were performed to assess the effect of multiple covariates including method of delivery on fracture-related outcomes. Results When accounting for other covariates, at-birth fracture rates did not differ based on whether delivery was by vaginal route or by cesarean section (CS). Increased birth weight conferred higher risk for fractures irrespective of the delivery method. In utero fracture, maternal history of OI, and breech presentation were strong predictors for choosing CS for delivery. Conclusion Our study, the largest to analyze the effect of various factors on at-birth fracture rates in OI shows that delivery by CS is not associated with decreased fracture rate. With the limitation that the fracture data were self-reported in this cohort, these results suggest that CS should be performed only for other maternal or fetal indications, but not for the sole purpose of fracture prevention in OI.
Collapse
Affiliation(s)
- S Bellur
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - M Jain
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - D Cuthbertson
- College of Medicine, University of South Florida, Tampa, Florida, USA
| | - D Krakow
- Department of Orthopedic Surgery, University of California, Los Angeles, California, USA.,Department of Human Genetics, University of California, Los Angeles, California, USA.,Department of Obstetrics and Gynecology, University of California, Los Angeles, California, USA
| | - J R Shapiro
- Department of Bone and Osteogenesis Imperfecta, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - R D Steiner
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon, USA.,Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, Oregon, USA.,Marshfield Clinic Research Foundation and University of Wisconsin, Marshfield and Madison, Wisconsin, USA
| | - P A Smith
- Shriners Hospitals for Children, Chicago, Illinois, USA
| | - M B Bober
- Division of Medical Genetics, Alfred I. DuPont Hospital for Children, Wilmington, Delaware, USA
| | - T Hart
- Osteogenesis Imperfecta Foundation, Gaithersburg, Maryland, USA
| | - J Krischer
- College of Medicine, University of South Florida, Tampa, Florida, USA
| | - M Mullins
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - P H Byers
- Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, Washington, USA.,Department of Pathology, Division of Medical Genetics, University of Washington, Seattle, Washington, USA
| | - M Pepin
- Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, Washington, USA.,Department of Pathology, Division of Medical Genetics, University of Washington, Seattle, Washington, USA
| | - M Durigova
- Department of Orthopedic Surgery, Shriners Hospital for Children and McGill University, Montreal, Québec, Canada
| | - F H Glorieux
- Department of Orthopedic Surgery, Shriners Hospital for Children and McGill University, Montreal, Québec, Canada
| | - F Rauch
- Department of Orthopedic Surgery, Shriners Hospital for Children and McGill University, Montreal, Québec, Canada
| | - V R Sutton
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA
| | - B Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA
| | | | - S C Nagamani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA
| |
Collapse
|
3
|
Premkumar MH, Sule G, Nagamani SC, Chakkalakal S, Nordin A, Jain M, Ruan MZ, Bertin T, Dawson B, Zhang J, Schady D, Bryan NS, Campeau PM, Erez A, Lee B. Argininosuccinate lyase in enterocytes protects from development of necrotizing enterocolitis. Am J Physiol Gastrointest Liver Physiol 2014; 307:G347-54. [PMID: 24904080 PMCID: PMC4121640 DOI: 10.1152/ajpgi.00403.2013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Necrotizing enterocolitis (NEC), the most common neonatal gastrointestinal emergency, results in significant mortality and morbidity, yet its pathogenesis remains unclear. Argininosuccinate lyase (ASL) is the only enzyme in mammals that is capable of synthesizing arginine. Arginine has several homeostatic roles in the gut and its deficiency has been associated with NEC. Because enterocytes are the primary sites of arginine synthesis in neonatal mammals, we evaluated the consequences of disruption of arginine synthesis in the enterocytes on the pathogenesis of NEC. We devised a novel approach to study the role of enterocyte-derived ASL in NEC by generating and characterizing a mouse model with enterocyte-specific deletion of Asl (Asl(flox/flox); VillinCre(tg/+), or CKO). We hypothesized that the presence of ASL in a cell-specific manner in the enterocytes is protective in the pathogenesis of NEC. Loss of ASL in enterocytes resulted in an increased incidence of NEC that was associated with a proinflammatory state and increased enterocyte apoptosis. Knockdown of ASL in intestinal epithelial cell lines resulted in decreased migration in response to lipopolysaccharide. Our results show that enterocyte-derived ASL has a protective role in NEC.
Collapse
Affiliation(s)
- M. H. Premkumar
- 1Division of Neonatology, Texas Children's Hospital, Baylor College of Medicine;
| | - G. Sule
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - S. C. Nagamani
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - S. Chakkalakal
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - A. Nordin
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - M. Jain
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - M. Z. Ruan
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - T. Bertin
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - B. Dawson
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - J. Zhang
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - D. Schady
- 3Department of Pathology, Texas Children's Hospital, Houston;
| | - N. S. Bryan
- 4University of Texas Health Science Center at Houston, Texas;
| | - P. M. Campeau
- 2Department of Molecular and Human Genetics, Baylor College of Medicine;
| | - A. Erez
- 5Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel; and
| | - B. Lee
- 2Department of Molecular and Human Genetics, Baylor College of Medicine; ,6Howard Hughes Medical Institute, Houston, Texas
| |
Collapse
|
4
|
Mokhtarani M, Diaz GA, Rhead W, Berry SA, Lichter-Konecki U, Feigenbaum A, Schulze A, Longo N, Bartley J, Berquist W, Gallagher R, Smith W, McCandless SE, Harding C, Rockey DC, Vierling JM, Mantry P, Ghabril M, Brown RS, Dickinson K, Moors T, Norris C, Coakley D, Milikien DA, Nagamani SC, Lemons C, Lee B, Scharschmidt BF. Elevated phenylacetic acid levels do not correlate with adverse events in patients with urea cycle disorders or hepatic encephalopathy and can be predicted based on the plasma PAA to PAGN ratio. Mol Genet Metab 2013; 110:446-53. [PMID: 24144944 PMCID: PMC4108288 DOI: 10.1016/j.ymgme.2013.09.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 09/29/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Phenylacetic acid (PAA) is the active moiety in sodium phenylbutyrate (NaPBA) and glycerol phenylbutyrate (GPB, HPN-100). Both are approved for treatment of urea cycle disorders (UCDs) - rare genetic disorders characterized by hyperammonemia. PAA is conjugated with glutamine in the liver to form phenylacetyleglutamine (PAGN), which is excreted in urine. PAA plasma levels ≥ 500 μg/dL have been reported to be associated with reversible neurological adverse events (AEs) in cancer patients receiving PAA intravenously. Therefore, we have investigated the relationship between PAA levels and neurological AEs in patients treated with these PAA pro-drugs as well as approaches to identifying patients most likely to experience high PAA levels. METHODS The relationship between nervous system AEs, PAA levels and the ratio of plasma PAA to PAGN were examined in 4683 blood samples taken serially from: [1] healthy adults [2], UCD patients of ≥ 2 months of age, and [3] patients with cirrhosis and hepatic encephalopathy (HE). The plasma ratio of PAA to PAGN was analyzed with respect to its utility in identifying patients at risk of high PAA values. RESULTS Only 0.2% (11) of 4683 samples exceeded 500 μg/ml. There was no relationship between neurological AEs and PAA levels in UCD or HE patients, but transient AEs including headache and nausea that correlated with PAA levels were observed in healthy adults. Irrespective of population, a curvilinear relationship was observed between PAA levels and the plasma PAA:PAGN ratio, and a ratio>2.5 (both in μg/mL) in a random blood draw identified patients at risk for PAA levels>500 μg/ml. CONCLUSIONS The presence of a relationship between PAA levels and reversible AEs in healthy adults but not in UCD or HE patients may reflect intrinsic differences among the populations and/or metabolic adaptation with continued dosing. The plasma PAA:PAGN ratio is a functional measure of the rate of PAA metabolism and represents a useful dosing biomarker.
Collapse
Affiliation(s)
- M Mokhtarani
- Hyperion Therapeutics, 601 Gateway Blvd., Suite 200, South San Francisco, CA 94080, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|