Neutrophil gelatinase-associated lipocalin: its response to hypoxia and association with acute mountain sickness.
Acute Mountain Sickness (AMS) is a common clinical challenge at high altitude (HA). A point-of-care biochemical marker for AMS could have widespread utility. Neutrophil gelatinase-associated lipocalin (NGAL) rises in response to renal injury, inflammation and oxidative stress. We investigated whether NGAL rises with HA and if this rise was related to AMS, hypoxia or exercise. NGAL was assayed in a cohort (n = 22) undertaking 6 hours exercise at near sea-level (SL); a cohort (n = 14) during 3 hours of normobaric hypoxia (FiO2 11.6%) and on two trekking expeditions (n = 52) to over 5000 m. NGAL did not change with exercise at SL or following normobaric hypoxia. During the trekking expeditions NGAL levels (ng/ml, mean ± sd, range) rose significantly (P < 0.001) from 68 ± 14 (60-102) at 1300 m to 183 ± 107 (65-519); 143 ± 66 (60-315) and 150 ± 71 (60-357) at 3400 m, 4270 m and 5150 m respectively. At 5150 m there was a significant difference in NGAL between those with severe AMS (n = 7), mild AMS (n = 16) or no AMS (n = 23): 201 ± 34 versus 171 ± 19 versus 124 ± 12 respectively (P = 0.009 for severe versus no AMS; P = 0.026 for mild versus no AMS). In summary, NGAL rises in response to prolonged hypobaric hypoxia and demonstrates a relationship to the presence and severity of AMS.
Defence Medical Services, Lichfield WS14 9PY, UK ; Academic Department of Emergency Medicine, James Cook University Hospital, Middlesbrough TS4 3BW, UK ; Ministry of Defence Hospital Unit, Northallerton DL6 1JG, UK.
Adrian
A
Mellor
Christopher
C
Boos
Mike
M
Stacey
Tim
T
Hooper
Chris
C
Smith
Joe
J
Begley
Jo
J
Yarker
Rick
R
Piper
John
J
O'Hara
Rod
R
King
Steve
S
Turner
David R
DR
Woods
D000209:Acute-Phase Proteins; D000328:Adult; D000531:Altitude; D000532:Altitude Sickness / Q000097:blood / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D015444:Exercise; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000097:blood*; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood*; D008297:Male; D011518:Proto-Oncogene Proteins / Q000097:blood*
D000209:Acute-Phase Proteins; D015415:Biomarkers; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins