RESUMEN
The efficacy and tolerability of acarbose was studied in type 2 diabetic patients eating a typical Jamaican diet. The study was an open label parallel group study without placebo control. Of the 51 subjects recruited, five (9.8 percent) did not complete the study and were excluded from further analysis. Six (13 percent) of the remaining 46 had adverse side effects and did not complete the protocol. Of the remaining 40 (Gp A), acarbose was added to their previous regime of diet alone (n=15), [Gp B], oral hypoglycaemic agents, OHAs (n=17), [Gp C], or insulin (n=8), Gp D]. In addition, during the run in period all subjects had one session each with a dietitian and a diabetes educator. Over a 3 month period, significant reductions in average glucose (mmol) were observed in Gp B 10.5 ñ 1.1 to 8.4 ñ 0.9 (p<0.027) and, from 11.0 ñ 1.0 to 8.7 ñ 0.7 (p<0.01) in Gp C. Similarly, total glycosylated haemoglobin fell from 14.8 ñ 1.1 percent to 12.2 ñ 1.0 percent (p<0.016) in Gp B, from 14.8 ñ 1.1 to 11.9 ñ 1.1 percent (p<0.002) in Gp C, and from 14.1 ñ 1.4 to 11.8 ñ 1.4 (p<0.02) in Gp D. Twenty-three per cent (23 percent) of the patients experienced flatulence; 7.5 percent changes in bowel habits and 5 percent, abdominal cramps and discomfort. Acarbose is effective as monotherapy and as combination therapy with oral hypoglycaemic agents or insulin. Side effects were common, but tolerable.(Au)
Asunto(s)
Adulto , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Acarbosa/uso terapéutico , Diabetes Mellitus Tipo 2/dietoterapia , Dieta , Quimioterapia Combinada , Flatulencia/inducido químicamente , Hipoglucemiantes/efectos adversos , Jamaica , Resultado del Tratamiento , Insulina/uso terapéutico , Acarbosa/efectos adversosRESUMEN
This study was undertaken to examine the diabetogenicity of linamarin, the predominant cyanoglucoside found in cassava. Cassava is a food staple, widely consumed in Jamaica, suspected of inflicting the primary insult in the onset of malnutrition related diabetes dellitus (MRDM). Male and female mongrel dogs obtained from the preclinical animal house were maintained on a diet of cornmeal cooked with pieces of chicken, fortified with Purina Laboratory Chow and water ad libitum. Undernutrition was induced by giving a very small portion of cornmeal only, for 10 days. The recovered were re-fed the normal diet with added milk and multivitamin supplements. The total dog population was 35; 15 normals, 10 undernourished and 10 recovered. On each dog, testing blood sugar along with serum insulin and insulin receptor studies were done followed by a control glucose tolerance test (GTT). After feeding linamarin, a residence time of 0.5 hour was allowed to elapse before these investigations were repeated. Linamarin dosage of 40 mg/kg body weight had no effect on the blood sugar level or receptor activity in the normal dogs. Even at dosage of 60 mg/kg the recovered dogs showed no abnormality, while in the undernourished group a dosage of 20 mg/kg induced abnormally high (p<0.05) glucose levels with a concomittant decrease in serum insulin (p<0.05) and insulin binding (p<0.05) to mononuclear leucocytes. These results point to the possible aetiology of diabetes by "Toxic" food substances in the undernourished state. (AU)
Asunto(s)
Perros , 21003 , Diabetes Mellitus , Trastornos Nutricionales , Manihot/efectos adversosRESUMEN
This study was undertaken to examine the diabetogenicity of linamarin in dogs of different nutritional status. The total dog population was 35; 15 normals, 10 undernourished, and 10 recovered. The recovered dogs were the refed undernourished dogs, On each dog a fasting plasma insulin and insulin receptor studies were done, followerd by a controlled glucose tolerance test. After feeding linamarin. 0.5 hour was allowed to elapse before these investigations were repeated. In the linamarin-treated udernourished animal, plasma insulin and insulin binding to erythrocytes and mononuclear leucocytes were significantly (P> 0.01) lower than in the control animals, and this resulted in abnormally high glucose levels. Linamarin administration had no effect on plasma insulin, insulin binding, or blood sugar levels in the normal and recovered dogs. These results point to the possible aetiology of diabetes in the undernourished state by 'toxic' foods substances such as linamarin. (AU)
Asunto(s)
21003 , Perros , Nitrilos/toxicidad , Glucemia , Diabetes Mellitus/etiología , Trastornos Nutricionales/complicaciones , Manihot/toxicidadRESUMEN
A pilot study was conducted at the UHWI to evaluate the OGTT as a tool for identifying gestational diabetes in our clinic population. It was performed on 21 high-risk pregnant mothers. When the current WHO criteria for the diagnosis of gestational glucose intolerance were applied, one (1) patient was considered to have gestational diabetes (4.8 per cent), seven (7) patients had impaired glucose tolerance (33.3 per cent), and thirteen (13) were considered normal (61.9 per cent). Insulin levels were determined for 13 of the patients and, within the group of patients with normal OGTT, two distinct groups were identified. Seven of the patients in this group had insulin levels determined, and of these, three had insulin levels similar to that of the impaired glucose tolerance group. Two of these three patients had foetal macrosomia. The remaining four in this group with normal OGTT had normal insulin curves and normal foetal sizes. Six of the patients with impaired glucose tolerance had insulin levels determined and two presented with foetal macrosomia (33 per cent). The results indicate that in spite of screening for impaired carbohydrate metabolism in pregnancy there are still patients who are misdiagnosed by the present WHO criteria using OGTT. Insulin assays may be a more sensitive predictor of altered carbohydrate metabolism (AU)
Asunto(s)
Humanos , Femenino , Embarazo , Diabetes Gestacional/diagnóstico , Prueba de Tolerancia a la Glucosa , Macrosomía Fetal , Embarazo de Alto RiesgoRESUMEN
Hyperinsulinaemia with insulin resistance has been observed in pre-eclampsia. In this longitudinal study, we examined whether this state of insulin resistance preceded the development of eclampsia. At 12, 24 and 36 weeks of gestation and at 12 weeks post-partum in twenty-five primigravidae, insulin and glucose were measured in the fasting state and in samples collected during intravenous glucose tolerance tests (IVGTT). Five women were diagnosed as pre-eclamptic (PE) at 34 - 39 weeks' gestation. In these PE, there was hyperinsulinaemia in the fasting state at 24 weeks compared to the normal pregnant (NP) women, 20.07 ñ 8.31 mU/ml vs. 13.74 ñ 5.64 mU/ml, (p<0.05). The degree of hyperinsulinaemia increased and, at 36 weeks' gestation it was 26.4 ñ 7.7 mU/l in the PE compared to 13.1 ñ 6.1 mU/l in the NP, (p<0.0001). The sensitivity of this measure for predicting pre-eclampsia at mid-pregnancy (24 weeks) was 80 per cent which increased to 100 per cent in late pregnancy (36 weeks). The specificity of this measure went from 57 per cent in mid-pregnancy to 43 per cent in late pregnancy. The glucose levels in the fasting state were not different at any time in the study. In the IVGTT, the area under the insulin curve was significantly larger in the PE as a group compared to the NP, (p<0.05). The area under the glucose curve was not different between the two groups at any time. The rate of disappearance of glucose Kg was significantly larger in the PE as a group compared to the NP, (p<0.05). Hyperinsulinaemia in the fasting state precedes the development of pre-eclampsia. It has a high sensitivity but low specificity for predicting the development of pre-eclampsia. Hyperinsulinaemia in the fasting state may have some value in screening those primigravidae at risk for developing pre-eclampsia (AU)
Asunto(s)
Humanos , Femenino , Embarazo , Hiperinsulinismo , Preeclampsia , Resistencia a la Insulina , Prueba de Tolerancia a la GlucosaRESUMEN
The effect of zinc intake on plasma immunoreactive insulin-like growth factor-I (IR-IGF-1) was studied in 24 children (aged 3 to 24 mos) recovering from severe malnutrition. The children were randomly assigned to two groups for zinc supplementation. Twelve (Zn+) were given (2mg/kg/d) added to the recovery of diet, and 12 (ZN-) were not. There was no group difference in age, sex, anthropometric measurements or plasma IR-IGF-1 at baseline. Plasma IR-IGF-1 was significantly higher in the zinc supplemented children during recovery (p = 0.031). These results suggest that zinc intake stimulates IR-IGF-1 production. (AU)
Asunto(s)
Humanos , Lactante , Trastornos de la Nutrición del Niño , Factor I del Crecimiento Similar a la Insulina , Zinc , JamaicaRESUMEN
Insulin binding to erythrocyte receptors was compared in malnourished and control rats. Percentage specific insulin binding to malnourished rat erythrocytes was significantly lower than to control erythrocytes (P<0.001). The low insulin binding in the malnourished rat erythrocytes was accompanied by low insulin receptor affinity (P=0.035).(AU)
Asunto(s)
Ratas , 21003 , Eritrocitos/metabolismo , Insulina/metabolismo , Receptor de Insulina/metabolismo , Trastornos Nutricionales/metabolismo , Membrana Eritrocítica/metabolismo , Ratas EndogámicasAsunto(s)
Humanos , Lactante , Preescolar , Trastornos de la Nutrición del Niño/terapia , Factor I del Crecimiento Similar a la Insulina/metabolismo , Zinc/farmacocinética , Trastornos de la Nutrición del Niño/sangre , Trastornos del Crecimiento/etiología , Unión Proteica/efectos de los fármacos , Receptores de Somatotropina/efectos de los fármacos , Zinc/deficienciaRESUMEN
In this study, plasma insulin, C-peptide and glucose measurements were done on the fasting blood samples obtained from primigravid pre-eclamptic (PE) women and suitably matched normal pregnant (NP) controls. This was done in order to observe any differences in the pancreatic secretion of insulin between these two groups. Fasting hyperinsulinaemia was observed as a statistically significant feature in the PE. The fasting C-peptide and glucose levels were not significantly different between the two groups. From the fasting C-peptide levels observed it would appear that the hyperinsulinaemia observed in the PE was not the result of hypersecretion of insulin by the pancreas (AU)
Asunto(s)
Humanos , Femenino , Embarazo , Preeclampsia/sangre , Péptido C , InsulinaRESUMEN
Studies of insulin status in the malnourished child have been directed to (1) the acute metabolic effects related to the maintenance of fuel homeostasis, and (2) the long term effects involving the modulation of growth during malnutrition and subsequent rehabilitation. In this paper, an attempt has been made to review some of the studies in the malnourished child in which metabolic changes have been brought about by changes in the availability and action of insulin and other hormones (AU)
Asunto(s)
Humanos , Niño , Trastornos Nutricionales , Insulina/metabolismo , Zinc/metabolismoRESUMEN
The effect of a controlled stress (DPT inoculation) on the hormonal control of glucose homeostasis was investigated in children nutritionally rehabilitated from severe malnutrition. The age range of the 15 children studied was 6-26 months. Plasma insulin (INS), growth hormone (GH) and interleukin-1 (IL-1) were measured by radioimmunoassay; plasma glucose (GLU) by a glucoseoxidase method; and red cell insulin binding ( percentSB) was determined, using A-14 monoiodinated insulin. Measurements were made on two occasions: (T-O) at 10 a.m.,12 hr before DPT inoculation, and (T-36) 36 hr. after inoculation. On both occasions, 4 hr post-prandial blood samples were used, and the mean body temperature(T) on the day of the test was determined. Red cell insulin binding ( percentSB) was significantly higher at T-36 than at T-O (16.8 ñ 1.7 vs 12.1 ñ 1.2 (14), p=0.005). (Results were expressed as mean ñ SEM, numbers of paired observations in parentheses). The higher percentSB after DPT was accompanied by an increase in the number of receptor sites (S) (29.05 ñ 6.5 vs 15.6 ñ 2.5 (14),p=0.025). However, insulin receptor affinity (K x 10(9)M(-1)) was decreased 0.7 ñ 0.1 vs 1.5 ñ 0.3(14), p=0.008). There were no significant differences in the plasma levels of insulin, glucose and interleukin-1, but plasma growth hormone (æU/ml) was increased after DPT, (18.0 ñ 3.0 vs 11.5 ñ 1.2 (13), p=0.04). Body temperature (§C) was also significantly increased after DPT,(99.9 ñ 0.4 vs 98.3 ñ 0.2(14), p=0.006). The change in plasma glucose from T-O to T-36 tended to be associated with both a change in plasma insulin (p=0.06) and plasma growth hormone (p=0.07). Increased insulin binding, as one index of increased insulin sensitivity during fever, can contribute to a reduction in blood glucose. However, the elevation in plasma growth hormone cold buffer the hypoglycaemic effect of insulin, and help to maintain glucose homeostasis (AU)
Asunto(s)
Lactante , Humanos , Vacuna contra Difteria, Tétanos y Tos Ferina/efectos adversos , Glucemia/metabolismo , Trastornos de la Nutrición del Niño/sangre , Hormonas/sangre , Homeostasis/efectos de los fármacos , Temperatura Corporal , Plasma , Insulina/sangre , Interleucina-1/sangre , Hormona del Crecimiento/sangre , RadioinmunoensayoRESUMEN
This study was designed to investigate any differences in cellular binding of insulin between phasic insulin-dependent (malnutrition-related) diabetes mellitus (PIDDM) and insulin-dependent, non-insulin-dependent, and normal controls. Isolated, washed red and white blood cells obtained after 12-14 hr fast, were separately incubated with varying concentrations of non-radioactive insulin, and a fixed quantity of radioactively labelled insulin. After the 3-hr incubation, cells were washed with buffer, and radioactivity determined on an autogamma counter. Percentage binding, receptor sites number an affinity were all determined by linear regression of the Scatchard plot. Fasting plasma insulin and glucose levels were also assayed. The results obtained showed decreased binding of insulin in red blood cells (11.3 ñ 1.3 percent) and white blood cells 2.9 ñ 0.5 percent) in PIDDM. This was due to decreased receptor sites (red blood cells 39 ñ 11; white blood cells 0.5 ñ 0.11 x 10 to the 4th) as well as decreased affinity (red blood cells 0.14 ñ 0.03 x 10 to the 9 M to the -1) when compared to the normal and diabetes (malnutrition-related diabetes mellitus) is characterized by decreased red and white cellular binding to insulin, in addition to decreased production of insulin.(AU)
Asunto(s)
Humanos , Diabetes Mellitus/sangre , Eritrocitos/metabolismo , Leucocitos Mononucleares/metabolismo , Trastornos Nutricionales/metabolismo , Receptor de Insulina/análisis , Diabetes Mellitus/etiología , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Trastornos Nutricionales/complicacionesRESUMEN
Significant hormonal changes have been reported in childhood malnutrition, including high serum levels of growth hormone and cortisol, and low levels of circulating insulin. The ultrastructure of the endocrine pancreas in such patients has hitherto not been reported. A light microscopy survey of the pancreatic islets was carried out on 69 malnourished children dying from protein-energy malnutrition. In seven of these cases, a rapid autopsy protocol allowed tissues to be fixed for electron microscopy within 75 minutes of death. This paper presents the first ultrastuctural observations on the Islets of Langerhans in childhood protein-energy malnutrition. In all cases, there was a variable degree of degereration of all cell types with membrane damage, loss of ribosomes, vesiculation and mitochondrial swelling. In addition, the B-cells showed a high proportion of precursor granules compared to crystal forms, possibly accounting for low insulin serum levels reported by other workers. It is suggested that islet cell changes may be related to free radical damage secondary to depletion of glutathione and other antioxidants, as well as relative deficiencies of cysteine and zinc. In addition, the effects of agonal anoxia, and a short fixation delay after death must be considered. (AU)
Asunto(s)
Humanos , Lactante , Masculino , Femenino , Islotes Pancreáticos/ultraestructura , Desnutrición Proteico-Calórica/patología , Páncreas/patología , Microscopía Electrónica , Desnutrición Proteico-Calórica/complicaciones , Desnutrición Proteico-Calórica/fisiopatologíaRESUMEN
The effect of a controlled stress (DPT innoculation) on the hormonal control of glucose homeostasis was investigated in children nutritionally rehabilitated from severe malnutrition. The age range of the 15 children studied was 6-26 months. Plasma insulin (INS), growth hormone (GH), interleukin-1 (IL-1) were measured by radio-immunoassay, plasma glucose (GLU) by a glucose oxidase method, and red cell insulin binding (RCIB) was determined using A-14 monoiodinated insulin. Measurements were made on two occasions: (1) at 10:00 a.m., 12 hrs. before DPT innoculation, and (2) 36 hrs. after innoculation. On both occasions, 4-hr. post-prandial blood samples were used, and the mean body temperature (BT) on the day of the test was determined. Plasma INS (æU/ml), GH (æU/ml), RCIB (percentage) and BT (C) were higher after DPT than before, plasma G1U (mM) was lower after DPT, and plasma IL-1 (fM/ml) was unchanged. The higher RCIB (percentage) after DPT was associated with an increase in the number of receptor sites (S), and a decrease in receptor affinity (K). The results (expressed as means ñ SEM) are summarized in the Table given. Significant positive correlations were shown between GLU and INS (r = +0.56, p < 0.015), and between IL-1 and RCIB (r = +0.66, p < 0.01) before DPT, but these relationships disappeared after DPT. A significant negative correlation was shown between glucose and insulin binding (r = -0.47). p < 0.05), when values before and after DPT were pooled. The results suggest that increased insulin binding may contribute to the lowering of blood glucose levels during the inflammatory response (AU)
Asunto(s)
Humanos , Lactante , Niño , Trastornos de la Nutrición del Niño , Vacuna contra Difteria, Tétanos y Tos Ferina , Glucemia/metabolismo , RadioinmunoensayoRESUMEN
Red cell insulin binding was studied in 13 Jamaican children (age range 4-24 months), while malnourished (MAL), during early recovery (GI), late recovery (GII), and after anthropometric recovery (REC). The rate of weight gain (RW), the energy intake (EN), and the protein intake (PR) were monitored at each phase of the study. Four-hour fasting blood samples were used, and the insulin binding characteristics were investigated in the physiological range of insulin concentrations (16.7-1670 pM). Analyses of variance were used to examine differences in the variables measured at the four phases. Red cell-specific insulin binding (SB) was lower in MAL than in GI (P<0.001) and in (GII) (P=0.026). SB in REC and MAL were not significantly different. Insulin receptor affinity (K) was also lower in MAL than in GI (P<0.001), GII (P<0.001), and REC (P=0.012). The insulin receptor number (S) appeared to be high in malnutrition and to decrease as recovery progressed; however, the decrease was not significant. Children with fever demonstrated high insulin binding. Plasma insulin (IN) rose during recovery, and was significantly higher in GII than in MAL (P=0.01). There was no difference in plasma glucose (G) at any phase of the study. The interrelationships among the variables measured were investigated longitudinally using multiple regression analyses. SB was positively associated with S (P=0.032), EN (P=0.029), and PR (P=0.0076). S was negatively associated with K (P<0.001). The associations of S and K with PR were positive and approached significance (P = 0.09 and P = 0.07 respectively). RW was positively associated with PR (P<0.001), and with EN (P=0.001). There were no significant relationships between G and any of the other variables longitudinally. However, correlations of the variables within phases demonstrated that in MAL, G was negatively associated with SB (P<0.05) and with K (P<0.05); but in REC, G was positively associated with SB (P<0.05). These results demonstrated that in severe malnutrition, the red cell insulin receptor affinity was low. During catch-up growth when protein and energy intakes were increased, both insulin receptor affinity and specific insulin binding were also increased. The negative relationship between insulin binding and plasma glucose during malnutrition may be related to carbohydrate intolerance (AU)
Asunto(s)
Humanos , Lactante , Preescolar , Eritrocitos/metabolismo , Trastornos Nutricionales/sangre , Receptor de Insulina/sangre , Análisis de Varianza , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Metabolismo Energético , Aumento de PesoRESUMEN
In normal pregnancies (NP), carbohydrate metabolism as assessed by oral glucose tolerance is impaired. This study was aimed at assessing whether a complication of pregnancy, pre-eclampsia (PE), exacerbates this impairment of carbohydrate metabolism. Results showed that the fasting plasma glucose levels were not significantly different between the PE (4.62ñ0.27 mM/1) and the NP (4.12ñ0.08 mM/1). However, the fasting plasma insulin levels were significantly higher in the PE (28.4ñ5.9 uU/m1) than in the NP (9.6ñ2.3 uU/m1) (p<0.01). Analysis of the area under the curve showed that the glucose response curves were not significantly different. The insulin response curves displayed a trend of higher circulating insulin levels in the PE compared to the NP; (p<0.07). The insulin to glucose ratio, an index of insulin sensitivity, in the PE (6.21ñ1.37) was significantly higher than that of the NP (2.26ñ0.54) p<0.05). We suggest that the hypertensive complication of pregnancy, PE, is accompanied by hyperinsulinaemia in the basal or fasting state, with an accompanying insulin insensitivity (AU)
Asunto(s)
Humanos , Femenino , Adulto , Prueba de Tolerancia a la Glucosa , Preeclampsia/diagnóstico , Carbohidratos/metabolismo , Complicaciones del Embarazo , Insulina/uso terapéuticoRESUMEN
Plasma somatomedin-C (pSm-C) was measured by immunoassay in Nigerian malnourished children treated with a mainly vegetable diet. In oedematous children, the mean intake was 4.31ñ0.23 g protein and 611ñ46 kJ per kg body weight per day, and in marasmic children 5.22ñ0.62 g protein and 795ñ131 kJ/kg body weight/d. PSm-C concentration (U/ml) was measured at weekly intervals to determine the response to this rehabilitation diet. By our assay the value for 39 normal children (age range 6-36 months) was 0.315ñ0.035 U/ml. The average initial level of pSm-C in the malnourished children was 0.19ñ0.03 (n=24). The values were higher (P<0.05) in the 7 marasmic children (0.26ñ0.1) than in the 11 with oedema (0.15ñ0.02). Eight days after admission pSm-C had risen to 0.20ñ0.02 (n=24) and at discharge after approximately 19d, pSm-C concentration was normal, 0.30ñ0.05. In oedematous malnutrition, pSm-C level at discharge was lower than in marasmus, 0.27ñ0.06 (n=17) compared with 0.37ñ0.06 (n=7) (P<0.05). Because the childrens' stay in hospital was short (average 19d), they were far from attaining normal weight for height by the time of discharge. However, they had gained on average 0.9 kg and their clinical condition was satisfactory. It is concluded that the vegetable-based diet produced satisfactory recovery, at least in the initial stages. Increases in pSm-C compared well with those found in an earlier study with milk-based diets. (AU)
Asunto(s)
Humanos , Lactante , Preescolar , Factor I del Crecimiento Similar a la Insulina/metabolismo , Trastornos Nutricionales/dietoterapia , Somatomedinas/metabolismo , Proteínas de Vegetales Comestibles/administración & dosificación , Nigeria , Trastornos Nutricionales/sangre , Trastornos Nutricionales/rehabilitaciónAsunto(s)
Humanos , Niño , Trastornos de la Nutrición del Niño , Diabetes Mellitus/etiología , KwashiorkorRESUMEN
Plasma somatomedin -C (PSm-C) was measured by radioimmunoassay in children with marasmus or kwashiorkor (4-24 months) and during rehabilitation. PSm-C (U/ml) was compared with that of normal children of the same age range (4-6 months, 0.175ñ0.04: 7-12 months, 0.288ñ0.35: 13-18 months 0.289ñ0.120: 19-24 months, 0.598ñ0.160). Initially, Jamaican children were offered one of two isocaloric diets (468J/kg body weight per day), which differed principally in their protein contents A-0.9g:B-3.5/kg body weight per day) at levels which did not permit anabolism. During this phase, oedematous children lost their oedema. They were then offered an energy dense diet (C-1046 KJ and 5.7g protein/kg body weight per day) and gained weight rapidly to achieve the weight of a normal child of the same height. The malnourished Nigerian children were treated with a vegetable-protein based diet which provided a mean intake of 4.3ñ0.2 gm protein and 556+34 KJ/kg body weight per day. PSm-C concentration in both Jamaica and Nigerian children was determined on admission and at weekly intervals during rehabilitation to examine the response to, and hence nutritional adequacy of both types of diets. In Jamaica children, PSm-C was slightly higher in admission but did not differ significantly in marasmic or kwashiorkor children (0.202ñ0.04 (n=9) vs 0.155ñ0.3 U/ml (n=18) respectively). In Nigerian children, PSm-C was higher in marasmic children (0.29ñ0.03 U/ml (n=7) than those with oedematous manutrition (0.15ñ0.03 U/ml (n=18) p<0.05). In both Jamaican and Nigerian children, PSm-C gradually rose after a small initial decline 1 week after admission. In Jamaican children, the increase in PSm-C after 4 weeks in hospital was significantly greater in marasmus than in kwashiorkor (0.431ñ0.71 (n=7) vs 0.269ñ0.05 U/ml (n=16) p<0.01). This difference could be attributed to dietary treatment, since oedematous children were kept from one to three weeks on a maintenance diet (either A or B) until oedema was lost. There was no significant difference in PSm-C on either diet A or B (A-0.165+0021 (n=26). B-0 150+0.019 U/ml (n=29). After 1 week on Diet C, PSm-C was 0.259ñ0.044 (n=21); significantly greater than PSm-C on diet A or B. In Nigerian children, eight days after admission, PSm-C had risen to 0.21ñ0.06 U/ml. In both Jamaican and Nigerian children, after 4 weeks PSm-C rose to normal values for their age range: 0.337ñ0.34 U/ml (n=21) in Jamaican children and 0.30ñ0.07 U/ml (n=25) in Nigerian children. The higher PSm-C shown in marasmic Jamaican children may be related to the early introduction of high energy Diet C (AU)
Asunto(s)
Estudio Comparativo , Humanos , Lactante , Preescolar , Factor I del Crecimiento Similar a la Insulina , Trastornos de la Nutrición del Niño/dietoterapia , Jamaica , NigeriaRESUMEN
Chronic nutrient inadequacy, as exemplified by marasmus and kwashiorkor provides a model for insulin-binding studies. Red cell insulin receptors were studies in infants (age range 4 to 24 months) whilst malnourished and at 3 different stages of anthropometric recovery (60-84, 85-95, and 96-110 percent weight-for-height (EWH)). Four-hour fasting blood samples (3 ml) were used. Washed red cells (concentration 0.75 - 1.5x10 Esp 9/ml) were incubated at 15§C for 180 min in the presence of a constant amount of tracer (A[14] - I[125] - insulin, 16.6 - 1680 pM, 7 different concentrations). Non-specific binding was assessed by the radioactive insulin bound in 10,000 x the physiological range of insulin concentration. From the competitive binding curve, total binding, affinity and number of receptor sites were calculated by Scatchard analysis. Specific insulin-binding was expressed as the per cent of total A[14] -I[125]-insulin added at a cell concentration of 4x10Exp9/ml. Red cell specific insulin-binding (SB) in malnutrition (rate of weight change, (RWC) - 2.05ñ1.9 (10) g/kg/d) was 4.2ñ0.8 (12) percent. This was significantly less than at all three phases of recovery (p<0.01). At 60-84 percent EWH(RWC ñ 11.7ñ0.9 (20)), SB was 8.6ñ1.2 (20) percent: at 96 -110 percent EWH (RWC ñ 0.95ñ1.1 (11)), SB was 8.8ñ1.4 (11) percent. A significantly (p<0.01) lower affinity of insulin for its receptor was shown in malnutrition, 0.9ñ0.2 (12) (Kx10Exp-8 M) than at other phases of recovery, 1.8ñ0.1 (24), 1.6ñ0.2 (20), and 1.4ñ0.4 (11) respectively. There were no significant changes in the number of receptor sites during malnutrition or during the catch-up growth phases. There was a highly significant positive correlation between rate of weight change and specific insulin-binding, (r= 0.45, p<0.0001 (67) as compared with plasma insulin concentration (r=0.33, p<0.01). Specific insulin-binding was also significantly correlated with the affinity of insulin for its receptor 9 r=0.28) p<0.05 (67)). Preliminary Results suggest that decreased protein, but not the carbohydrate or fat content of the diet, was associated with reduced insulin receptor affinity. Chronic nutritional inadequacy alters the affinity of the red cell receptor for insulin, leading to decreased binding, and this is quickly reversed early in rehabilitation. Decreased insulin-binding may be related to the carbohydrate intolerance of severe malnutrition (AU)