- Email: [email protected]
Mediators of postoperative insulin resistance
Methods: 15 patients commenced on home enteral nutrition (HEN) were identified from a supply register. 7 had gastrointestinal pathology, 6 had neurological disease, 1 anorexia nervosa and 1 carcinoma. 8 were receiving supplemental EN and 7 total EN. 6 were receiving 2 litres of feed and all but 1 were prescribed sufficient feed to meet estimated requirements. Nutritional status was assessed using anthropometry (body mass index (BMI), triceps skinfold thickness (TSF) and mid upper arm circumference (MUAC)). Blood was taken for measurement of serum albumin, magnesium, zinc, copper, selenium and vitamins A and E. Results: Mean duration of feeding was 7.5 months (range 2.30 months). 7 patients had anthropometric evidence of protein and energy depletion (BMI < 20 and TSF or MUAC < 15th percentile) of whom 6 were severely depleted (BMI < 18 and TSF or MUAC < 5th percentile). Serum albumin was below the normal reference range (36-50 g/l) in only 3 patients. 12 patients had biochemical evidence of trace element or vitamin depletion of whom 6 had multiple (>3) depletion. 7 patients had zinc depletion (12 /imol/l), 6 had selenium depletion (selenium < 0.8 pmol and red cell glutathione peroxidase i 13 units/gHb) and 4 had vitamin A depletion (~1 .O pmol). Magnesium and copper levels were low in 2 patients (co.7 mmol/l and ~10 pmol/l respectively) and 1 patient had a low vitamin E level ( < 14 pmol/l). Depletion occurred in all diagnostic categories, even in patients with normal anthropometric measurements, and was independent of duration or volume of feeding. Conclusion: Patients receiving HEN are at risk of developing vitamin or trace element deficiency states regardless of diagnosis, anthropometric measurements or duration of feeding. Therefore close nutritional monitoring of such patients is essential, and it is recommended that patients on HEN are supervised by clinicians with appropriate interest. Acknowledgement to The Trace Element Unit, Institute of Biochemistry, The Royal Infirmary, Glasgow.
Topic 15-HORMONES P.69 Reduced muscle protein breakdown in septic rats following treatment with interleukin-I receptor antagonist 0. Zsmir’, P. 0. Hasselgren, J. E. Fischer Departments of Surgery, University of Cincinnati Medical Center, Cincinnati, Ohio, and ‘Hadassah University Hospital Mount Scopus, Jerusalem Sepsis and trauma are characterized by increased breakdown in skeletal muscle. Cytokines, Interleukin-1 (IL-l) in particular, have been suggested as mediators responsible for this response. Using a specific IL-l receptor antagonist (IL-l ra) we examined the role of IL-1 in muscle proteolysis during sepsis. Methods: Male S-D rats (40-60 g) underwent cecal ligation and puncture (CLP) to induce sepsis or sham operation. Animals in each group were treated with IL-l ra (25 mg/kg) injected i.p. in 5 doses at 4 h intervals starting 1 h before CLP or control injection. Sixteen hours after CLP or sham operation intact extensor digitorum longus muscles were dissected and incubated. Protein breakdown rate was determined as release of tyrosine during 2 h incubation. Results: Protein breakdown rate was increased by more than two-fold following CLP. This response was significantly reduced by IL-lra treatment (Table).
P.68 Effect of selenium supplementation on muscle biopsies in selenium depleted patients on home parenteral nutrition. T. Rannem, K. Ladefoged, J. Halkjeer Kristensen and H. Laursen Division of Gastroenterology, Rheumatology and Neuropatology, Rigshospitalet, Copenhagen, Denmark Several case reports of muscular weakness or muscular pain which respond to selenium (Se) substitution have been published in patients on total parenteral nutrition. Extremely low blood Se values have been found in patients with no obvious clinical symptoms, and the clinical significance of Se deficiency is therefore not well established. Material: A biopsy of the quadriceps muscle was taken before and after intravenous substitution for 4 months with 200 pg Se per day as natriumselenite (Selenase”) in 9 patients on home parenteral nutrition. The patients had been on Se-free parenteral nutrition for 21-l 68, median 58 months. Prior to Se substitution all patients had low plasma Se: O0.51 pmol/l. median 0.21 pmol/l (control group 0.75-l .86, median 1 .ll pmol/l). After Se supplementation all patients had Se levels within normal range. Results:
Mean dnmeter Atrophy factor Hypetrophy factor Mean diameter Athrophy factor Hypertrophy factor
Flbre type 1
Fibre type 2
Before Se median (range) 57 (47-70) 20 (o-39) 12 (140) g3 {“A;;’
After Se median (range) 59 (50-83) 9 (3-21) 12 (W12) y; y;)
9 (O-90)
29 (O-51
)
p = 0.01 p = 0.11 p=O.O6 ; 1 yJJ p = 0.29
Conclusion: The study demonstrated a significant increase of the diameter of type 1 muscle fibre following Se supplementation in Se depleted patients. This supports the suggestions of a skeletal myopathy related to Se deficiency.
AND
MEDIATORS SHAM
Tyrosme release
IL-1 ra 229+8
E&y;
CLP Solvent 571143
IL-lra 469+22‘
Results are in nmol/gx2 h (mean + SEM). n = 6-8 in each group. p < 0.05 vs. all other groups (ANOVA followed by Tukey’s test). Conclusion: Results indicate that muscle proteolysis induced by sepsis can be attenuated by treatment with ILlra, suggesting that IL-l is involved in increased muscle proteolysis during sepsis.
P.70 Mediators resistance
of
postoperative
A. Thorell & 0. Ljungqvist Dept. of Surgery, Karolinska Hospital, Stockholm,
insulin
Sweden
Elective surgery has been shown to induce a state of insulin resistance. The degree of reduction of insulin sensitivity seems to be increased with greater magnitude of surgery performed. Less is known with regard to the mechanisms related to the development of insulin resistance. Presently, the possibility of a covariation between the degree of postoperative changes in relative insulin sensitivity and con-
P.72 Insulin-like growth factor-l improves protein metabolism and reduces gut mucosal atrophy after surgery in rats with cirrhosis. T. Inaba, H. Saito, M. Lin, T. Inoue, R. Fukushima and T.
comitant levels of stress hormones and interleukin-6 (IL-6) was investigated. Methods: 31 patients, otherwise healthy, operated electively for inguinal hernia repair (group H, n = 7) or open cholecystectomy (group C) were included in the study. insulin sensitivity was determined using the hyperinsulinemic, normoglycemic clamp technique (plasma insulin approximately 380 pmol/ml. blood glucose 4.5 mmol/l) preoperatively and on the first postoperative day. In addition, 5 of the patients in group C were studied on day 5, 9 and 20 postoperatively. Immediately prior to each clamp, blood sampling for plasma levels of stress hormones (glucagon, adrenaline, noradrenaline, cortisol, GH) and IL-6 was performed. The relative insulin sensitivity is given as per cent of preoperative values. Simple regression analysis and nonparametric methods were used. Results: All patients displayed reduced insulin sensitivity on the first postoperative day. More pronounced reductions in insulin sensitivity was found after surgery in group C. No such difference was seen in any of the stress hormones. There was a linear relationship between relative insulin sensitivity and concomitant levels of IL-6 (r = 0.63, p < 0.001). However, no such correlation could be confirmed for any of the stress hormones (r < 0.16, p 2 0.24) Conclusions: The observation of significantly higher plasma levels of IL-6 between groups on the first postoperative day, together with the significant relationship between relative insulin sensitivity and IL-6, suggests a possible role for this cytokine in the development of postoperative insulin resistance, while the role of the stress hormones remains uncertain.
Muto Department of Surgery, University of Tokyo, Tokyo, Japan The altered protein metabolism and endotoxin translocation appear to be related to a high risk of postoperative morbidity and mortality in liver cirrhosis. Insulin-like growth factor-l (IGF-1) has been shown to improve nitrogen metabolism and to reduce gut mucosal atrophy after surgical trauma. However, these effects on cirrhotic subjects are not well understood. The purpose of this study was to examine the effects of IGF-1 on postoperative protein metabolism and gut integrity in cirrhotic rats. Cirrhosis was induced by oral administration of 0.05% thioacetamide for 6 months. Fifteen cirrhotic rats received total parenteral nutrition (100 kcal/kg/ day and 0.49 gN/kg/day) after gastrectomy. In addition, continuous intravenous infusion of 4 mg/kg/day of IGF-1, the most effective dose in non-cirrhotic rats, or placebo were given for 3 postoperative days. Whole-body protein turnover and fractional synthesis rate (FSR) of tissue protein were determined using 15 N-glycine constant infusion method on the third postoperative day. Mucosal height of the small intestine was also determined. Control Serum IGF-1 724i123 @g/ml) Nitrogen Excretion 595*29 hMk9/dav) Nitrogen Balance -267+28 (ms/ks/dw) Whole-body Protein Flux (gN/kg/day) 2 23iO.10 Svnthew 1.62kO.12 (3WWdav) Breakdown 1.73+0.10 ‘9N’;;ij;;j Liver FSR 14.lk1.3 Gastrocnemius FSR 1.24t0.12 Intestinal mucosal height 540 + 26 ‘“~?I MeankSE ‘p < 0.05 YS control “p: 0.06 vs co&l “‘p Student t-test
P.71 Influences on insulin-like growth factor1 in burned infected rats. D. D. Lazarus, S. A. Stackpole, W. J. Montegut, E. Fischer,
The result suggests that IGF-1 improves protein metabolism and reduces intestinal mucosal atrophy after surgery in cirrhotic rats. We conclude that exogenous IGF-1 infusion may be useful for the postoperative treatment in patients with liver cirrhosis.
L. L. Moidawer, S. F. Lowry Cornell University Medical College, NY, NY, USA 1002 I The role of insulin-like growth factor-l (IGF-1) in the loss of lean tissue that accompanies injury has not been determined. To investigate this, we measured changes in plasma levels of this hormone after a 30% BSA scald burn which was infected with Pseudomonas aeruginosa. To examine the involvement of interleukin-1 (IL-l ) and tumor necrosis factor-a (TNFa) in this model, we treated burned/infected (B/l) animals with antagonists to these cytokines: IL-I receptor antagonist, (IL-l ra, 36 mg/kg/day), and the TNF soluble receptor, (sTNFr, 2 mg/kg/2 days), respectively. Because of the decline in food intake, a group that was pairfed to untreated burned/infected animals was included. On day 7, body weights and plasma IGF-1, using an RIA after separation from IGF binding proteins, were measured. Results are mean f. SEM, n = 4-g/group, statistics used NewmanKeul’s MRT, * = p < 0.05 v. sham, ** = p < 0.05 v. sham and pair-fed. Treatment Sham PM-fed B/I+Vehicle B/l+sTNFr B/I+IL-lra
;$;il+@/mt) 575 T45’ 116&28” 191 f43” 162k46”
BW change +16+4 -29+2. -8OT6” -75*9*. -51 k6’”
IGF-1 (4 mglkglday) 2500+486* 464+35’ -144+35+ 2.73iO.12’ 2.25tO.15’ 2.31 kO.13’ l&3+0.9 1.74+0.24”’ 615+24” < 0.08;s control
P.73 Growth hormone stimulation dietary supplementation with ornithine glutarate (OKG) in trauma rats.
due to a keto-
M. Jeevanandam, N. J. Holaday, R. Ali, andS. R. Petersen Trauma Center, St. Joseph’s Hospital & Medical Center, Phoenix, AZ, USA An acute deficiency of growth hormone (GH) is noted in hypercatabolic injury state. Stimulation of this anabolic GH would enhance the metabolic status. The relative efficacy of ornithine (ORN) and its salts with u ketoglutaric acid (OKG) or ketoisocaproic acid (OKIC) in stimulating GH and insulin secretion is investigated. A group of male Sprague-Dawley rats (260+2 g) had bilateral femur fracture (T) and another group (C) without injury acted as control. All rats were provided with water alone for 2 days. On the 3rd day feeding was started and continued for 4 days. T & C rats were randomized among 4 isonitrogenous liquid diets. The basic diet was casein-based, BioServ Diet, # F1259. The other 3 test diets were the basic diet from which 10% nitrogen (N) was replaced by ORN-N or OKG-N or OKIC-N. T rats were pair-fed to respective C rats. Daily weight, intake, and urinary data were collected. After 4 days of feeding the rats were sacrificed and blood was collected for hormonal analysis. The results (mean +SEM, n = 6 each group) are:
(g/7 days)
A correlation of the IGF-1 levels in these groups with the accompanying body weight changes shows that r2 = 0.93. The diminished food intake could only partly account for the significant decline in circulating IGF-1, as well as the loss of body weight, in burned/infected animals. As blockade of IL1 and TNFa did not attenuate these changes, we conclude that these,cytokines are not important mediators of IGF-1 in this model. 56
Topic 15-HORMONES P.69 Reduced muscle protein breakdown in septic rats following treatment with interleukin-I receptor antagonist 0. Zsmir’, P. 0. Hasselgren, J. E. Fischer Departments of Surgery, University of Cincinnati Medical Center, Cincinnati, Ohio, and ‘Hadassah University Hospital Mount Scopus, Jerusalem Sepsis and trauma are characterized by increased breakdown in skeletal muscle. Cytokines, Interleukin-1 (IL-l) in particular, have been suggested as mediators responsible for this response. Using a specific IL-l receptor antagonist (IL-l ra) we examined the role of IL-1 in muscle proteolysis during sepsis. Methods: Male S-D rats (40-60 g) underwent cecal ligation and puncture (CLP) to induce sepsis or sham operation. Animals in each group were treated with IL-l ra (25 mg/kg) injected i.p. in 5 doses at 4 h intervals starting 1 h before CLP or control injection. Sixteen hours after CLP or sham operation intact extensor digitorum longus muscles were dissected and incubated. Protein breakdown rate was determined as release of tyrosine during 2 h incubation. Results: Protein breakdown rate was increased by more than two-fold following CLP. This response was significantly reduced by IL-lra treatment (Table).
P.68 Effect of selenium supplementation on muscle biopsies in selenium depleted patients on home parenteral nutrition. T. Rannem, K. Ladefoged, J. Halkjeer Kristensen and H. Laursen Division of Gastroenterology, Rheumatology and Neuropatology, Rigshospitalet, Copenhagen, Denmark Several case reports of muscular weakness or muscular pain which respond to selenium (Se) substitution have been published in patients on total parenteral nutrition. Extremely low blood Se values have been found in patients with no obvious clinical symptoms, and the clinical significance of Se deficiency is therefore not well established. Material: A biopsy of the quadriceps muscle was taken before and after intravenous substitution for 4 months with 200 pg Se per day as natriumselenite (Selenase”) in 9 patients on home parenteral nutrition. The patients had been on Se-free parenteral nutrition for 21-l 68, median 58 months. Prior to Se substitution all patients had low plasma Se: O0.51 pmol/l. median 0.21 pmol/l (control group 0.75-l .86, median 1 .ll pmol/l). After Se supplementation all patients had Se levels within normal range. Results:
Mean dnmeter Atrophy factor Hypetrophy factor Mean diameter Athrophy factor Hypertrophy factor
Flbre type 1
Fibre type 2
Before Se median (range) 57 (47-70) 20 (o-39) 12 (140) g3 {“A;;’
After Se median (range) 59 (50-83) 9 (3-21) 12 (W12) y; y;)
9 (O-90)
29 (O-51
)
p = 0.01 p = 0.11 p=O.O6 ; 1 yJJ p = 0.29
Conclusion: The study demonstrated a significant increase of the diameter of type 1 muscle fibre following Se supplementation in Se depleted patients. This supports the suggestions of a skeletal myopathy related to Se deficiency.
AND
MEDIATORS SHAM
Tyrosme release
IL-1 ra 229+8
E&y;
CLP Solvent 571143
IL-lra 469+22‘
Results are in nmol/gx2 h (mean + SEM). n = 6-8 in each group. p < 0.05 vs. all other groups (ANOVA followed by Tukey’s test). Conclusion: Results indicate that muscle proteolysis induced by sepsis can be attenuated by treatment with ILlra, suggesting that IL-l is involved in increased muscle proteolysis during sepsis.
P.70 Mediators resistance
of
postoperative
A. Thorell & 0. Ljungqvist Dept. of Surgery, Karolinska Hospital, Stockholm,
insulin
Sweden
Elective surgery has been shown to induce a state of insulin resistance. The degree of reduction of insulin sensitivity seems to be increased with greater magnitude of surgery performed. Less is known with regard to the mechanisms related to the development of insulin resistance. Presently, the possibility of a covariation between the degree of postoperative changes in relative insulin sensitivity and con-
P.72 Insulin-like growth factor-l improves protein metabolism and reduces gut mucosal atrophy after surgery in rats with cirrhosis. T. Inaba, H. Saito, M. Lin, T. Inoue, R. Fukushima and T.
comitant levels of stress hormones and interleukin-6 (IL-6) was investigated. Methods: 31 patients, otherwise healthy, operated electively for inguinal hernia repair (group H, n = 7) or open cholecystectomy (group C) were included in the study. insulin sensitivity was determined using the hyperinsulinemic, normoglycemic clamp technique (plasma insulin approximately 380 pmol/ml. blood glucose 4.5 mmol/l) preoperatively and on the first postoperative day. In addition, 5 of the patients in group C were studied on day 5, 9 and 20 postoperatively. Immediately prior to each clamp, blood sampling for plasma levels of stress hormones (glucagon, adrenaline, noradrenaline, cortisol, GH) and IL-6 was performed. The relative insulin sensitivity is given as per cent of preoperative values. Simple regression analysis and nonparametric methods were used. Results: All patients displayed reduced insulin sensitivity on the first postoperative day. More pronounced reductions in insulin sensitivity was found after surgery in group C. No such difference was seen in any of the stress hormones. There was a linear relationship between relative insulin sensitivity and concomitant levels of IL-6 (r = 0.63, p < 0.001). However, no such correlation could be confirmed for any of the stress hormones (r < 0.16, p 2 0.24) Conclusions: The observation of significantly higher plasma levels of IL-6 between groups on the first postoperative day, together with the significant relationship between relative insulin sensitivity and IL-6, suggests a possible role for this cytokine in the development of postoperative insulin resistance, while the role of the stress hormones remains uncertain.
Muto Department of Surgery, University of Tokyo, Tokyo, Japan The altered protein metabolism and endotoxin translocation appear to be related to a high risk of postoperative morbidity and mortality in liver cirrhosis. Insulin-like growth factor-l (IGF-1) has been shown to improve nitrogen metabolism and to reduce gut mucosal atrophy after surgical trauma. However, these effects on cirrhotic subjects are not well understood. The purpose of this study was to examine the effects of IGF-1 on postoperative protein metabolism and gut integrity in cirrhotic rats. Cirrhosis was induced by oral administration of 0.05% thioacetamide for 6 months. Fifteen cirrhotic rats received total parenteral nutrition (100 kcal/kg/ day and 0.49 gN/kg/day) after gastrectomy. In addition, continuous intravenous infusion of 4 mg/kg/day of IGF-1, the most effective dose in non-cirrhotic rats, or placebo were given for 3 postoperative days. Whole-body protein turnover and fractional synthesis rate (FSR) of tissue protein were determined using 15 N-glycine constant infusion method on the third postoperative day. Mucosal height of the small intestine was also determined. Control Serum IGF-1 724i123 @g/ml) Nitrogen Excretion 595*29 hMk9/dav) Nitrogen Balance -267+28 (ms/ks/dw) Whole-body Protein Flux (gN/kg/day) 2 23iO.10 Svnthew 1.62kO.12 (3WWdav) Breakdown 1.73+0.10 ‘9N’;;ij;;j Liver FSR 14.lk1.3 Gastrocnemius FSR 1.24t0.12 Intestinal mucosal height 540 + 26 ‘“~?I MeankSE ‘p < 0.05 YS control “p: 0.06 vs co&l “‘p Student t-test
P.71 Influences on insulin-like growth factor1 in burned infected rats. D. D. Lazarus, S. A. Stackpole, W. J. Montegut, E. Fischer,
The result suggests that IGF-1 improves protein metabolism and reduces intestinal mucosal atrophy after surgery in cirrhotic rats. We conclude that exogenous IGF-1 infusion may be useful for the postoperative treatment in patients with liver cirrhosis.
L. L. Moidawer, S. F. Lowry Cornell University Medical College, NY, NY, USA 1002 I The role of insulin-like growth factor-l (IGF-1) in the loss of lean tissue that accompanies injury has not been determined. To investigate this, we measured changes in plasma levels of this hormone after a 30% BSA scald burn which was infected with Pseudomonas aeruginosa. To examine the involvement of interleukin-1 (IL-l ) and tumor necrosis factor-a (TNFa) in this model, we treated burned/infected (B/l) animals with antagonists to these cytokines: IL-I receptor antagonist, (IL-l ra, 36 mg/kg/day), and the TNF soluble receptor, (sTNFr, 2 mg/kg/2 days), respectively. Because of the decline in food intake, a group that was pairfed to untreated burned/infected animals was included. On day 7, body weights and plasma IGF-1, using an RIA after separation from IGF binding proteins, were measured. Results are mean f. SEM, n = 4-g/group, statistics used NewmanKeul’s MRT, * = p < 0.05 v. sham, ** = p < 0.05 v. sham and pair-fed. Treatment Sham PM-fed B/I+Vehicle B/l+sTNFr B/I+IL-lra
;$;il+@/mt) 575 T45’ 116&28” 191 f43” 162k46”
BW change +16+4 -29+2. -8OT6” -75*9*. -51 k6’”
IGF-1 (4 mglkglday) 2500+486* 464+35’ -144+35+ 2.73iO.12’ 2.25tO.15’ 2.31 kO.13’ l&3+0.9 1.74+0.24”’ 615+24” < 0.08;s control
P.73 Growth hormone stimulation dietary supplementation with ornithine glutarate (OKG) in trauma rats.
due to a keto-
M. Jeevanandam, N. J. Holaday, R. Ali, andS. R. Petersen Trauma Center, St. Joseph’s Hospital & Medical Center, Phoenix, AZ, USA An acute deficiency of growth hormone (GH) is noted in hypercatabolic injury state. Stimulation of this anabolic GH would enhance the metabolic status. The relative efficacy of ornithine (ORN) and its salts with u ketoglutaric acid (OKG) or ketoisocaproic acid (OKIC) in stimulating GH and insulin secretion is investigated. A group of male Sprague-Dawley rats (260+2 g) had bilateral femur fracture (T) and another group (C) without injury acted as control. All rats were provided with water alone for 2 days. On the 3rd day feeding was started and continued for 4 days. T & C rats were randomized among 4 isonitrogenous liquid diets. The basic diet was casein-based, BioServ Diet, # F1259. The other 3 test diets were the basic diet from which 10% nitrogen (N) was replaced by ORN-N or OKG-N or OKIC-N. T rats were pair-fed to respective C rats. Daily weight, intake, and urinary data were collected. After 4 days of feeding the rats were sacrificed and blood was collected for hormonal analysis. The results (mean +SEM, n = 6 each group) are:
(g/7 days)
A correlation of the IGF-1 levels in these groups with the accompanying body weight changes shows that r2 = 0.93. The diminished food intake could only partly account for the significant decline in circulating IGF-1, as well as the loss of body weight, in burned/infected animals. As blockade of IL1 and TNFa did not attenuate these changes, we conclude that these,cytokines are not important mediators of IGF-1 in this model. 56