Rupali Vohra1, Line Marie Dalgaard1, Jeppe Vibaek1, Mia Aggergaard Langbøl1, Linda Hildegaard Bergersen2,3, Niels Vidiendal Olsen4,5, Bjørnar Hassel6,7, Farrukh Abbas Chaudhry8,9, Miriam Kolko1,10. 1. Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark. 2. Center of Healthy Ageing, University of Copenhagen, Copenhagen, Denmark. 3. Brain and Muscle Energy Group, Faculty of Dentistry, Department of Oral Biology, University of Oslo, Oslo, Norway. 4. Department of Neuroanaesthesia, The Neuroscience Centre, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark. 5. Department of Biomedical Science, University of Copenhagen, Copenhagen, Denmark. 6. Department of Complex Neurology and Neurohabilitation, Oslo University Hospital, University of Oslo, Oslo, Norway. 7. Norwegian Defence Research Establishment (FFI), Kjeller, Norway. 8. Department of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway. 9. Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway. 10. Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet-Glostrup, Glostrup, Denmark.
Abstract
PURPOSE: To assess novel differences in serum levels of glucose, lactate and amino acids in patients with normal-tension glaucoma (NTG) compared to age-matched controls, at baseline and in response to universal hypoxia. METHODS: Twelve patients diagnosed with NTG and eleven control subjects underwent normobaric hypoxia for 2 hr. Peripheral venous blood samples were taken at baseline, during hypoxia and in the recovery phase. Serum glucose and lactate levels were measured by a blood gas analyser. Amino acids were analysed by high-performance liquid chromatography. RESULTS: Baseline levels of lactate and total amino acids were significantly lower in patients with NTG compared to healthy controls. No differences were seen in blood glucose levels between the two groups. Lactate levels remained unchanged during hypoxia in the control group, but increased in patients with NTG. In the recovery phase, total amino acid levels were reduced in the control group, whereas no changes were found in patients with NTG. CONCLUSION: Reduced serum levels of lactate and total amino acids were identified as potential markers for NTG. Moreover, significant differential regulatory patterns of certain amino acids were found in patients with NTG compared to control subjects. Overall, our results suggest a link between systemic energy metabolites and NTG and support a novel understanding of glaucoma as an inner retinal manifestation of a systemic condition.
PURPOSE: To assess novel differences in serum levels of glucose, lactate and amino acids in patients with normal-tension glaucoma (NTG) compared to age-matched controls, at baseline and in response to universal hypoxia. METHODS: Twelve patients diagnosed with NTG and eleven control subjects underwent normobaric hypoxia for 2 hr. Peripheral venous blood samples were taken at baseline, during hypoxia and in the recovery phase. Serum glucose and lactate levels were measured by a blood gas analyser. Amino acids were analysed by high-performance liquid chromatography. RESULTS: Baseline levels of lactate and total amino acids were significantly lower in patients with NTG compared to healthy controls. No differences were seen in blood glucose levels between the two groups. Lactate levels remained unchanged during hypoxia in the control group, but increased in patients with NTG. In the recovery phase, total amino acid levels were reduced in the control group, whereas no changes were found in patients with NTG. CONCLUSION: Reduced serum levels of lactate and total amino acids were identified as potential markers for NTG. Moreover, significant differential regulatory patterns of certain amino acids were found in patients with NTG compared to control subjects. Overall, our results suggest a link between systemic energy metabolites and NTG and support a novel understanding of glaucoma as an inner retinal manifestation of a systemic condition.
Authors: Mia Langbøl; Sarkis Saruhanian; Thisayini Baskaran; Daniel Tiedemann; Zaynab A Mouhammad; Anne Katrine Toft-Kehler; Bokkyoo Jun; Rupali Vohra; Nicolas G Bazan; Miriam Kolko Journal: J Clin Med Date: 2020-09-15 Impact factor: 4.241