Clinical Nutrition xxx (2013) 1e7
Contents lists available at ScienceDirect
Clinical Nutrition journal homepage: http://www.elsevier.com/locate/clnu
Original article
Glutamine depletion and heat shock protein 70 (HSP70) in children with meningococcal disease L.V. Marino a, *, N. Pathan b, R. Meyer c, V. Wright a, P. Habibi a a
Department of Paediatrics, Imperial College London, United Kingdom Department of Paediatrics, University of Cambridge, United Kingdom c Department of Gastroenterology, Great Ormond Street Hospital for Sick Children, London, United Kingdom b
a r t i c l e i n f o
s u m m a r y
Article history: Received 22 February 2013 Accepted 25 September 2013
Background & aims: Heat shock proteins are classified into six main families, of which HSP70 is the best studied. HSP70 is postulated to modulate the immune/inflammatory response in critical illness. Glutamine promotes HSP70 release, however, little is known about the relationship between glutamine and HSP70 in paediatric critical illness. We therefore aimed to describe plasma levels of HSP70, inflammatory mediators and glutamine in critically ill children. Methods: A clinical audit identified 143 children with severe meningococcal disease, 78 convalescent children, in addition to 35 healthy paediatric controls. Stored plasma was used to measure plasma concentrations of HSP70, inflammatory mediators and glutamine. Results: HSP70 was significantly increased on admission (n ¼ 143, mean 26.7 ng/ml; SD 79.95) compared with convalescence (n ¼ 78, mean 3.16 ng/ml; SD 5.67). Glutamine levels were low (n ¼ 132, mean 0.31 mmol/l; SD 0.13), which continued in convalescence (n ¼ 65, mean 0.40 mmol/l; SD 0.14). Enteral glutamine provided only 28% of the recommendations. Glutamine was inversely correlated with length-of-stay (n ¼ 98, r ¼ 0.520, p < 0.001), ventilation (n ¼ 98, r ¼ 0.513, p < 0.001), lactate (n ¼ 98, r ¼ 0.41, p < 0.001) and CRP (n ¼ 98, r ¼ 0.51, p < 0.001). HSP70 was correlated with length-of-stay (n ¼ 99, r ¼ 0.30, p < 0.001), ventilation (n ¼ 99, r ¼ 0.31, p < 0.001), lactate (n ¼ 99, r ¼ 0.26, p < 0.001) and CRP (n ¼ 99, r ¼ 0.29, p < 0.001) and inflammatory mediators. There was no relationship between glutamine and HSP70 or inflammatory mediators. Conclusions: During acute illness HSP70/inflammatory mediators are significantly increased, and glutamine is significantly depleted. However, glutamine and HSP70 were not correlated. Enteral feeds only provided a small proportion of the ASPEN/ESPEN recommendations for glutamine. Ó 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism.
Keywords: Critical illness Glutamine HSP70 Inflammatory mediators Enteral feeding Meningococcal disease
What is known: Glutamine is a conditionally essential amino acid during critical illness. Low levels of plasma glutamine are reported during times of stress. Glutamine is effective in promoting the release of heat shock protein 70 (HSP70). Following glutamine supplementation, increased levels of HSP70 are associated with decreased mortality in
* Corresponding author. Department of Nutrition and Dietetics, University Hospital Southampton NHS Foundation Trust, Norfolk Place, Southampton S016 6YD, United Kingdom. Tel.: þ44 (0) 23 8079 6072. E-mail addresses: [email protected], [email protected] (L.V. Marino).
septic animal models, although little is known about its effect in critically ill children. Recent work suggests that in critically ill replete adults, glutamine supplementation is associated with increased mortality.
What this study adds: Low levels of plasma glutamine and high HSP70 levels were found in children with meningococcal disease during the acute phase of illness. However, there was no relationship between glutamine and HSP70 in this cohort. Enteral feeds, delivered at goal rate, only provided a small proportion of the recommended 0.5 g/kg/day of glutamine.
0261-5614/$ e see front matter Ó 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. http://dx.doi.org/10.1016/j.clnu.2013.09.013
Please cite this article in press as: Marino LV, et al., Glutamine depletion and heat shock protein 70 (HSP70) in children with meningococcal disease, Clinical Nutrition (2013), http://dx.doi.org/10.1016/j.clnu.2013.09.013
2
L.V. Marino et al. / Clinical Nutrition xxx (2013) 1e7
1. Introduction Neisseria meningitidis is one of the most significant human pathogens causing sepsis and meningitis1 and is associated with a potent inflammatory response resulting in shock and multi-organ failure.2 Inflammation, co-ordinated by the innate immune system, is a necessary response to infection promoting increased blood flow to the injured site. However when excessive, this response may result in tissue and cell damage, affecting protein homeostasis resulting in misfolding and clumping of proteins.3 Heat shock proteins (HSP) are highly conserved intracellular ‘housekeeping’ proteins which maintain cell function.4 During infection, the HSP response is rapid, occurring within minutes of stress recognition, restoring protein homeostasis and reestablishing normal growth conditions.5 Numerous HSP’s have been described and are classified into 6 main families; HSP27, HSP40, HSP60, HSP70, HSP90 and HSP110. The HSP70 family is one of the most well studied6 and is believed to protect the host from further tissue damage by modulating the inflammatory response during critical illness.7 There has been a significant interest in HSP70’s role during critical illness, since an experimental burn rat model and adults with severe burns were shown to have an upregulation of HSP70 expression, protecting against organ damage and leading to increased survival.8 HSP70 is therefore thought to play an important role in the modulation of the innate immune response in sepsis.9 Glutamine (Gln) enhances the release of HSP7010 and may therefore modulate the host response to infection.11 Gln is regarded as a conditionally essential amino acid during times of stress12 and depletion in critically ill adults is associated with increased morbidity and mortality.13 Previously glutamine has been regarded as safe, non-toxic and easy to administer potentially representing an attractive modulator of the heat shock response.10 Previous meta-analysis of randomised controlled trials of parenteral nutrition (PN) supplemented with glutamine showed an associated decreased length of ICU stay and ventilator days,16 although there are no such similar reports of the effects of Gln supplementation on outcomes in critically ill children.17 Conversely, recent work suggests that glutamine depletion may not always occur in critically ill adults with septic shock, as only 31% of the patients admitted had low glutamine levels in contrast to 15% of patients had supra physiological glutamine levels, which was associated with increased mortality. Rodas et al. have corroborated these finding showing that high plasma glutamine levels (>930 mmmol/l) were associated with an increased mortality.14,15 The objective of this study was to describe plasma levels of HSP70, markers of inflammation and Gln in critically ill children with meningococcal disease. 2. Materials and methods All children admitted with suspected meningococcal disease to PICU of St. Mary’s Hospital, London between 1996 and 2007 had a venous blood sample taken at the time of admission (local research ethics approval: reference number 09/H0712/98). Diagnosis was confirmed by isolation of N. meningitidis from blood, cerebral spinal fluid, and/or by polymerase chain amplification of meningococcal DNA from peripheral blood.18 Whole blood, collected in EDTA tubes, was centrifuged for 10 min at 1200 g, plasma harvested and stored at 80 C. Convalescent blood samples were collected from children during outpatient follow-up, on average 55 days (range 35e153) post discharge from the PICU and processed as above. Blood samples were also obtained from healthy age-matched paediatric controls. All biochemical and immunological data was obtained from the same blood sample.
Table 1 Patient demographics, clinical variables and PICU support of children with acute meningococcal disease. Number (%) Decimal age (years) Weight (kg) Weight for age Z scores PRISMa PIM2a Days on PICU ICU free days Duration of ventilation Deaths Renal support Inotropes Steroids Noradrenaline (mcg/kg/min) Adrenaline (mcg/kg/min) Dobutamine (mcg/kg/min) Dopamine (mcg/kg/min) Urea (mmol/l) Creatinine (mmol/L) Glucose (mmol/l) WCC ( 109/l) Platelets ( 109/l) INR CRP (mg/l) Potassium (mmol/l) Base Excess (mEq/L) Lactate (mmol/l) Sodium (mmol/l) Albumin (g/L) Calcium corrected (mmol/l) Phosphate (mmol/l) Magnesium (mmol/l) a
1 to 1
Median
Range (minemax)
Mean (SD)
2.0
0.02e17.2
3.1 (3.1)
12 0.1
3e70 4.1 to 4.8
15.3 (10.4) 0.2 (1.2)
26 9.1 7 21 6
10e89.8 3.6e65.5 3e63 0e25 2e45
31.9 13.7 8.8 18.7 7.4
(20.3) (18.4) (7.6) (6.7) (5.9)
7 (4.7%) 124 (81%) 123 (83%) 108 (73%)
2.5e7.8 60e120 3.9e6 4.0e11.0 150e400 0.9e1.2
Contents lists available at ScienceDirect
Clinical Nutrition journal homepage: http://www.elsevier.com/locate/clnu
Original article
Glutamine depletion and heat shock protein 70 (HSP70) in children with meningococcal disease L.V. Marino a, *, N. Pathan b, R. Meyer c, V. Wright a, P. Habibi a a
Department of Paediatrics, Imperial College London, United Kingdom Department of Paediatrics, University of Cambridge, United Kingdom c Department of Gastroenterology, Great Ormond Street Hospital for Sick Children, London, United Kingdom b
a r t i c l e i n f o
s u m m a r y
Article history: Received 22 February 2013 Accepted 25 September 2013
Background & aims: Heat shock proteins are classified into six main families, of which HSP70 is the best studied. HSP70 is postulated to modulate the immune/inflammatory response in critical illness. Glutamine promotes HSP70 release, however, little is known about the relationship between glutamine and HSP70 in paediatric critical illness. We therefore aimed to describe plasma levels of HSP70, inflammatory mediators and glutamine in critically ill children. Methods: A clinical audit identified 143 children with severe meningococcal disease, 78 convalescent children, in addition to 35 healthy paediatric controls. Stored plasma was used to measure plasma concentrations of HSP70, inflammatory mediators and glutamine. Results: HSP70 was significantly increased on admission (n ¼ 143, mean 26.7 ng/ml; SD 79.95) compared with convalescence (n ¼ 78, mean 3.16 ng/ml; SD 5.67). Glutamine levels were low (n ¼ 132, mean 0.31 mmol/l; SD 0.13), which continued in convalescence (n ¼ 65, mean 0.40 mmol/l; SD 0.14). Enteral glutamine provided only 28% of the recommendations. Glutamine was inversely correlated with length-of-stay (n ¼ 98, r ¼ 0.520, p < 0.001), ventilation (n ¼ 98, r ¼ 0.513, p < 0.001), lactate (n ¼ 98, r ¼ 0.41, p < 0.001) and CRP (n ¼ 98, r ¼ 0.51, p < 0.001). HSP70 was correlated with length-of-stay (n ¼ 99, r ¼ 0.30, p < 0.001), ventilation (n ¼ 99, r ¼ 0.31, p < 0.001), lactate (n ¼ 99, r ¼ 0.26, p < 0.001) and CRP (n ¼ 99, r ¼ 0.29, p < 0.001) and inflammatory mediators. There was no relationship between glutamine and HSP70 or inflammatory mediators. Conclusions: During acute illness HSP70/inflammatory mediators are significantly increased, and glutamine is significantly depleted. However, glutamine and HSP70 were not correlated. Enteral feeds only provided a small proportion of the ASPEN/ESPEN recommendations for glutamine. Ó 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism.
Keywords: Critical illness Glutamine HSP70 Inflammatory mediators Enteral feeding Meningococcal disease
What is known: Glutamine is a conditionally essential amino acid during critical illness. Low levels of plasma glutamine are reported during times of stress. Glutamine is effective in promoting the release of heat shock protein 70 (HSP70). Following glutamine supplementation, increased levels of HSP70 are associated with decreased mortality in
* Corresponding author. Department of Nutrition and Dietetics, University Hospital Southampton NHS Foundation Trust, Norfolk Place, Southampton S016 6YD, United Kingdom. Tel.: þ44 (0) 23 8079 6072. E-mail addresses: [email protected], [email protected] (L.V. Marino).
septic animal models, although little is known about its effect in critically ill children. Recent work suggests that in critically ill replete adults, glutamine supplementation is associated with increased mortality.
What this study adds: Low levels of plasma glutamine and high HSP70 levels were found in children with meningococcal disease during the acute phase of illness. However, there was no relationship between glutamine and HSP70 in this cohort. Enteral feeds, delivered at goal rate, only provided a small proportion of the recommended 0.5 g/kg/day of glutamine.
0261-5614/$ e see front matter Ó 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. http://dx.doi.org/10.1016/j.clnu.2013.09.013
Please cite this article in press as: Marino LV, et al., Glutamine depletion and heat shock protein 70 (HSP70) in children with meningococcal disease, Clinical Nutrition (2013), http://dx.doi.org/10.1016/j.clnu.2013.09.013
2
L.V. Marino et al. / Clinical Nutrition xxx (2013) 1e7
1. Introduction Neisseria meningitidis is one of the most significant human pathogens causing sepsis and meningitis1 and is associated with a potent inflammatory response resulting in shock and multi-organ failure.2 Inflammation, co-ordinated by the innate immune system, is a necessary response to infection promoting increased blood flow to the injured site. However when excessive, this response may result in tissue and cell damage, affecting protein homeostasis resulting in misfolding and clumping of proteins.3 Heat shock proteins (HSP) are highly conserved intracellular ‘housekeeping’ proteins which maintain cell function.4 During infection, the HSP response is rapid, occurring within minutes of stress recognition, restoring protein homeostasis and reestablishing normal growth conditions.5 Numerous HSP’s have been described and are classified into 6 main families; HSP27, HSP40, HSP60, HSP70, HSP90 and HSP110. The HSP70 family is one of the most well studied6 and is believed to protect the host from further tissue damage by modulating the inflammatory response during critical illness.7 There has been a significant interest in HSP70’s role during critical illness, since an experimental burn rat model and adults with severe burns were shown to have an upregulation of HSP70 expression, protecting against organ damage and leading to increased survival.8 HSP70 is therefore thought to play an important role in the modulation of the innate immune response in sepsis.9 Glutamine (Gln) enhances the release of HSP7010 and may therefore modulate the host response to infection.11 Gln is regarded as a conditionally essential amino acid during times of stress12 and depletion in critically ill adults is associated with increased morbidity and mortality.13 Previously glutamine has been regarded as safe, non-toxic and easy to administer potentially representing an attractive modulator of the heat shock response.10 Previous meta-analysis of randomised controlled trials of parenteral nutrition (PN) supplemented with glutamine showed an associated decreased length of ICU stay and ventilator days,16 although there are no such similar reports of the effects of Gln supplementation on outcomes in critically ill children.17 Conversely, recent work suggests that glutamine depletion may not always occur in critically ill adults with septic shock, as only 31% of the patients admitted had low glutamine levels in contrast to 15% of patients had supra physiological glutamine levels, which was associated with increased mortality. Rodas et al. have corroborated these finding showing that high plasma glutamine levels (>930 mmmol/l) were associated with an increased mortality.14,15 The objective of this study was to describe plasma levels of HSP70, markers of inflammation and Gln in critically ill children with meningococcal disease. 2. Materials and methods All children admitted with suspected meningococcal disease to PICU of St. Mary’s Hospital, London between 1996 and 2007 had a venous blood sample taken at the time of admission (local research ethics approval: reference number 09/H0712/98). Diagnosis was confirmed by isolation of N. meningitidis from blood, cerebral spinal fluid, and/or by polymerase chain amplification of meningococcal DNA from peripheral blood.18 Whole blood, collected in EDTA tubes, was centrifuged for 10 min at 1200 g, plasma harvested and stored at 80 C. Convalescent blood samples were collected from children during outpatient follow-up, on average 55 days (range 35e153) post discharge from the PICU and processed as above. Blood samples were also obtained from healthy age-matched paediatric controls. All biochemical and immunological data was obtained from the same blood sample.
Table 1 Patient demographics, clinical variables and PICU support of children with acute meningococcal disease. Number (%) Decimal age (years) Weight (kg) Weight for age Z scores PRISMa PIM2a Days on PICU ICU free days Duration of ventilation Deaths Renal support Inotropes Steroids Noradrenaline (mcg/kg/min) Adrenaline (mcg/kg/min) Dobutamine (mcg/kg/min) Dopamine (mcg/kg/min) Urea (mmol/l) Creatinine (mmol/L) Glucose (mmol/l) WCC ( 109/l) Platelets ( 109/l) INR CRP (mg/l) Potassium (mmol/l) Base Excess (mEq/L) Lactate (mmol/l) Sodium (mmol/l) Albumin (g/L) Calcium corrected (mmol/l) Phosphate (mmol/l) Magnesium (mmol/l) a
1 to 1
Median
Range (minemax)
Mean (SD)
2.0
0.02e17.2
3.1 (3.1)
12 0.1
3e70 4.1 to 4.8
15.3 (10.4) 0.2 (1.2)
26 9.1 7 21 6
10e89.8 3.6e65.5 3e63 0e25 2e45
31.9 13.7 8.8 18.7 7.4
(20.3) (18.4) (7.6) (6.7) (5.9)
7 (4.7%) 124 (81%) 123 (83%) 108 (73%)
2.5e7.8 60e120 3.9e6 4.0e11.0 150e400 0.9e1.2
