Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Limited proteolysis of serum insulin-like growth factor (IGF) binding protein (IGFBP)-3 has been described in various conditions and may increase the bioavailability of IGFs. The physiological regulators of serum IGFBP-3 protease activity are unknown. To characterize the relationship between insulin and IGFBP-3 protease activity, we have examined serum IGFBP-3 proteolysis in children with untreated insulin-dependent diabetes mellitus (IDDM) and have followed the effect of insulin therapy on serum IGFBP-3 proteolysis at 1 day, 1 week, and 1 month after the initiation of insulin therapy. Ligand blot analysis of sera from untreated children with IDDM showed that intact IGFBP-3 was 50 +/- 9% of the age-matched control pool. After the initiation of insulin treatment, IGFBP-3 did not change significantly at 1 day after treatment but increased dramatically at 1 week (90 +/- 13%) and 1 month after treatment (102 +/- 13%). In contrast, when measured by immunoradiometric assay (which detects both intact and fragments of IGFBP-3), IGFBP-3 levels were 70% of the control pool before insulin therapy and did not increase significantly until 1 month after treatment. Immunoblot analysis demonstrated that intact IGFBP-3 doublet was diminished to 41 +/- 7% of controls, whereas the major IGFBP-3 fragment (30 kDa) was increased in IDDM sera before insulin therapy. After insulin, intact IGFBP-3 increased and the 30-kDa fragment decreased to values comparable to those observed in controls. In vivo IGFBP-3 proteolysis, which implies preassay exposure of serum IGFBP-3 to proteases, was estimated by immunoblot analysis. IGFBP-3 proteolysis was increased before insulin therapy (160 +/- 9%) and decreased to 81 +/- 9% at 1 week and to 71 +/- 11% at 1 month after insulin treatment. Residual serum IGFBP-3 protease activity was estimated by a 125I-IGFBP-3 degradation assay. Serum IGFBP-3 protease activity increased significantly in untreated diabetics, compared with activity in controls (128 +/- 5% vs. 99 +/- 11%). During insulin therapy, serum IGFBP-3 protease activity decreased gradually to 91 +/- 5% of control values at 1 month. Molecular sizes of the IGFBP-3 proteolytic fragments (30 kDa, 24 kDa, and 19 kDa) and inhibition profile of IGFBP-3 protease were similar in IDDM and pregnancy sera, indicating that similar proteases (cation-dependent serine proteases) were active in both conditions. These results suggest an important role of insulin in the regulation of IGFBP-3 protease activity. Increased IGFBP-3 proteolysis in the sera of children with IDDM may serve to counteract the catabolic state induced by insulin deficiency.
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PMID:Insulin-like growth factor binding protein-3 proteolysis in children with insulin-dependent diabetes mellitus: a possible role for insulin in the regulation of IGFBP-3 protease activity. 754 9

To investigate whether previously reported increased levels of insulin-like growth factor-binding protein-1 (IGFBP-1) in GH-deficient patients only reflect decreased levels of insulin or are elevated in relation to insulin, diurnal profiles of IGFBP-1 and insulin were determined in plasma from patients with GH levels below 0.2 microgram/L throughout 24 h (n = 23) and compared to profiles from patients with insulin-dependent diabetes mellitus (IDDM; n = 9) and healthy subjects (n = 12). Samples were drawn using a continuous withdrawal technique at 20-min intervals. Levels of IGF-I were determined in one morning sample. As in healthy subjects, serum IGFBP-1 displayed a diurnal variation in GH-deficient as well as in IDDM patients, with lowest levels in the afternoon and evening and a rise with maximum levels during the night and morning. Fasting and 24-h mean levels of IGFBP-1 were significantly higher in GH-deficient patients [61 +/- 12 (P < 0.01) and 39 +/- 6 micrograms/L (P < 0.01), respectively] and IDDM patients [72 +/- 18 (P < 0.01) and 45 +/- 9 micrograms/L (P < 0.01), respectively] compared to those in healthy subjects (27 +/- 4 and 18 +/- 2 micrograms/L, respectively). Fasting levels of IGFBP-1 correlated to 24-h mean values of IGFBP-1 in all groups separately and in the combined group (r = 0.931; P < 0.001). An inverse relationship was found between IGFBP-1 and insulin in GH-deficient patients, both between 24-h mean values (r = -0.756; P < 0.001) and between fasting values (r = -0.721; P < 0.001). Corresponding values for healthy subjects were r = -0.548; P = 0.065 and r = -0.712; P < 0.01, respectively, whereas in IDDM patients the relationship was nonsignificant. Moreover, in GH-deficient patients, the diurnal mean levels of IGFBP-1 were inversely correlated to IGF-I (r = -0.477; P < 0.05) and body mass index (r = -0.450; P < 0.05). When insulin was taken into account, a tendency for a negative correlation between IGFBP-1 and IGF-I (P = 0.054) remained, whereas the relationship to body mass index disappeared. However, IGFBP-1 levels were elevated in relation to insulin levels in GH-deficient patients compared to healthy subjects (F = 48.7; P < 0.001 and F = 32.5; P < 0.001, diurnal mean values and fasting values, respectively). The majority of the IDDM patients had values in the same range as the GH-deficient patients.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Altered relation between circulating levels of insulin-like growth factor-binding protein-1 and insulin in growth hormone-deficient patients and insulin-dependent diabetic patients compared to that in healthy subjects. 754 95

To study the possible role of insulin-like growth factor binding proteins (IGFBPs) in the discrepancy between normal or only slightly retarded growth and substantially reduced concentrations of insulin-like growth factor I (IGF-I) in prepubertal children with insulin-dependent diabetes mellitus (IDDM), we measured the plasma concentrations of IGF-I, IGFBP-1, IGFBP-2 and IGFBP-3 and free insulin in 24 prepubertal diabetic subjects and 12 control children. In addition, the growth hormone response to exercise was evaluated. The diabetic children had significantly decreased peripheral IGF-I levels (8.2 + 1.1 (SEM) vs 16.7 + 2.5 nmol/l; p < 0.001), whereas the concentrations of free insulin were increased (217 + 14 vs 103 + 21 pmol/l; p < 0.001). The concentrations of IGFBP-1 and IGFBP-3 were of the same magnitude in both groups. The diabetic children had significantly increased levels of IGFBP-2 (465 + 13 vs 416 + 14 micrograms/l; p = 0.029), which were inversely related to the circulating IGF-I levels (r = -0.35; p = 0.034). The diabetic and control children had comparable growth hormone responses to exercise. Diabetic children with poor glucose control had even lower IGF-I levels than those with moderate metabolic control (6.0 + 0.8 vs 10.3 + 1.7 nmol/l; p = 0.037). No differences could be observed in the plasma concentrations of various IGFBPs between these two groups of diabetic subjects. The absence in prepubertal diabetic children of increased IGFBP-1 levels observed in adolescent and adult patients with IDDM may contribute to their maintained linear growth, despite definitely decreased IGF-I concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Insulin-like growth factor binding proteins in prepubertal children with insulin-dependent diabetes mellitus. 758 67

The experiments reported herein were conducted to determine how corticosterone regulates growth and plasma insulin-like growth factor (IGF) I and IGF-binding protein (IGFBP) concentrations in normal and streptozotocin (STZ)-induced diabetic rats. Males were bilaterally adrenalectomized (Ax) or sham Ax and given intravenous injections of 0, 30, or 65 mg STZ per kg body wt (0, 30, or 65 STZ) to induce varying degrees of insulin deficiency and implanted with 100-mg pellets containing 0, 40, or 80% corticosterone in cholesterol. Changes in plasma IGFBP concentrations were determined by Western ligand blotting or immunoblots. Neither IGFBP-5 nor IG-FBP-6 was detected in any of the treatment groups. Plasma IGFBP-2 was elevated and IGF-I was reduced in the nondiabetic Ax rats compared with sham Ax controls, but plasma IGFBP-3 and -4 were not significantly changed. Adrenalectomy had no affect on tibial growth or plasma IGFBP-1 in these animals. Plasma IGF-I, IGFBP-1 and -3, and tibial growth were equal among 0, 30, and 65 STZ Ax rats that did not receive corticosterone. Plasma IGFBP-4 was inversely related to the amount of STZ injected in these animals, and IGFBP-2 was elevated in those given the high dose of STZ. In the 0 STZ Ax rats, plasma IGF-I and IGFBP-3 increased in proportion to the corticosterone implant dose, but IGFBP-1 was unaffected. By contrast, IGF-I and IGFBP-3 were unaltered by corticosterone in the 30 STZ Ax rats, and IGFBP-1 increased in proportion with the dose of corticosterone.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1995 Dec
PMID:Corticosterone regulation of insulin-like growth factor I, IGF-binding proteins, and growth in streptozotocin-induced diabetic rats. 758 49

Circulating levels and hepatic expression of insulin-like growth factor-binding protein-1 (IGFBP-1) are increased in insulin-deficient streptozotocin (STZ)-diabetic rats. Glucocorticoids stimulate and insulin suppresses hepatocellular expression of IGFBP-1 in vitro. We asked whether increased IGFBP-1 expression in STZ-diabetic animals is due to an effect of insulin deficiency per se or whether insulin deficiency represents a permissive state where glucocorticoids may play an important role in the regulation of IGFBP-1 and other circulating peptides involved in the modulation of IGF bioactivity. Intact female Sprague-Dawley-derived rats and rats undergoing bilateral adrenalectomy (ADNX) were injected with STZ (140 mg/kg) or buffer. Corticosterone acetate (50 mg/kg) or vehicle was administered to diabetic and nondiabetic animals immediately after ADNX and 24 h later. All rats were killed 48 h after surgery and/or STZ administration. Serum [125I]IGF-I-binding activity was increased 4-fold (P < 0.01), and Western ligand and immunoblotting demonstrated that levels of IGFBP-1 were high in intact STZ-diabetic animals. ADNX prevented these effects of STZ-diabetes, and corticosterone treatment restored serum IGF-binding activity and IGFBP-1 to intact diabetic levels. Similarly, Northern analysis demonstrated that the abundance of hepatic IGFBP-1 mRNA was increased 6-fold in intact STZ-diabetic animals (P < 0.01), but not in adrenalectomized diabetic animals. Corticosterone treatment restored hepatic IGFBP-1 mRNA to intact diabetic levels, and serum concentrations of corticosterone correlated with the abundance of IGFBP-1 mRNA (r = 0.475; P < 0.01), indicating that glucocorticoids play an important role in the regulation of expression of IGFBP-1 in insulin-deficient animals. In contrast, neither ADNX nor corticosterone altered the abundance of hepatic IGFBP-1 mRNA levels in nondiabetic animals. This pattern of regulation appeared to be specific; serum levels of immunoreactive IGFBP-2 and -4 tended to rise in adrenalectomized animals, and levels of IGFBP-3 were not affected by either ADNX or corticosterone treatment. Of note, serum levels of IGF-I by RIA were reduced in STZ-diabetic animals compared to control values (168 +/- 16 vs. 587 +/- 55 ng/ml, respectively; P < 0.01), were partially restored toward control values with ADNX (320 +/- 22 ng/ml), and were reduced again by corticosterone treatment (195 +/- 26 ng/ml), indicating that glucocorticoids also contribute to the regulation of IGF-I levels in insulin-deficient animals. The abundance of IGF-I mRNA was reduced in STZ-diabetic animals, and ADNX also partially prevented this effect of diabetes.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of glucocorticoids on circulating levels and hepatic expression of insulin-like growth factor (IGF)-binding proteins and IGF-I in the adrenalectomized streptozotocin-diabetic rat. 769 41

To test the hypothesis that glucocorticoids inhibit muscle glucose transport apart from changes in early insulin-signaling events, we determined the effect of glucocorticoid treatment on the activation of glucose transport by both insulin and non-insulin-related stimuli (insulin-like growth factor [IGF] I and hypoxia) in rat skeletal muscle. Male Sprague-Dawley rats were treated with dexamethasone (Dex) (0.8 mg/kg for 2 days) and compared with pair-fed controls. 2-[3H]deoxyglucose (2-[3H]DG) uptake in isolated soleus muscles was measured under conditions in which uptake reflects glucose transport activity. In control muscles, 2-[3H]DG uptake was stimulated 10-fold by insulin (10 nmol/l) or IGF-I (50 nmol/l) and sixfold by hypoxia. Dex treatment decreased 2-[3H]DG uptake at all concentrations of insulin tested, reducing maximal insulin-stimulated 2-[3H]DG uptake by 41 +/- 11% (mean +/- SE, P < 0.05) and basal 2-[3H]DG uptake by 38 +/- 6% (P < 0.01). Dex treatment also inhibited 2-[3H]DG uptake at all concentrations of IGF-I tested, reducing maximal IGF-I-stimulated 2-[3H]DG uptake by 29 +/- 2% (P < 0.01), and decreased hypoxia-stimulated 2-[3H]DG uptake by 61% (P < 0.01). Dex treatment increased soleus GLUT4 protein content by 11%. Thus, Dex treatment reduces basal glucose transport and decreases the maximal response of skeletal muscle glucose transport to insulin, the related hormone IGF-I, and the non-insulin-related stimulus hypoxia. These findings support the hypothesis that, in addition to altering early insulin-signaling events, glucocorticoids may also act by inhibiting the glucose transport system, per se, perhaps by affecting GLUT4 subcellular trafficking.
Diabetes 1995 Apr
PMID:Glucocorticoid-induced insulin resistance: dexamethasone inhibits the activation of glucose transport in rat skeletal muscle by both insulin- and non-insulin-related stimuli. 769 14

Microvascular complications of diabetes can be forestalled by effective glycemic control. However, the inherent limitations of standard subcutaneous insulins reduce their ability to control glycemia without risk of significant hypoglycemia and hyperinsulinemia. Hypoglycemia is unacceptable for most patients and may be dangerous. Hyperinsulinemia is undesirable because it causes weight gain and it has a putative association with atherosclerosis. This paper summarizes the major historical improvements in insulin therapy, and calls attention to the fact that none of the presently available commercial preparations in any combination is capable of simulating the profile of normal insulin secretion--the latter being regarded as the most effective means of normalizing glycemia. For this reason, a variety of new approaches to simulating the pharmacokinetics or glucodynamics of insulin secretion are under investigation. Fast-acting insulin analogues suitable for subcutaneous injection have been developed and appear to mimic the physiological insulin response more closely than standard insulins. Less progress has been made with basal insulins. Intravenous insulin has pharmacodynamic advantages but practical disadvantages of administration. Nasal insulin would be an attractive treatment modality only if its bioavailability could be significantly increased and its safety assured. Other interventions which improve glucose metabolism without necessarily simulating normal insulin secretion are under investigation. These include biosynthetic human C-peptide, insulin-like growth factor-1 and glucagon-like peptide 1 (7-36 amide).
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PMID:Improving insulin therapy: achievements and challenges. 770 65

Diabetic renal hypertrophy is preceded by a transient increase in kidney insulin-like growth factor I and insulin-like growth factor binding protein concentration suggesting a renotropic function in diabetic kidney growth. In order to further examine the possible involvement of the insulin-like growth factor system in initial diabetic kidney growth, we have studied the expression of the kidney insulin-like growth factor II/mannose-6-phosphate receptor during the first 4 days after induction of diabetes in rats. Using a specific antiserum (#3637) raised against the insulin-like growth factor II/mannose-6-phosphate receptor of rat chondrosarcoma a specific band with an apparent molecular weight of 220 kDa was identified in Western blotting experiments with kidney and liver protein extracts. In untreated diabetic rats a transient increase of the kidney and liver insulin-like growth factor II/mannose-6-phosphate receptor concentration was measured 24-48 h after the induction of diabetes (mean increase in kidney 140% and liver 112%, n = 5). This increase was followed by a subsequent decrease in the insulin-like growth factor II/mannose-6-phosphate receptor protein concentration after 3-4 days of diabetes. Insulin treatment prevented the rise both in kidney and liver tissue. Kidney weight in untreated diabetic rats increased by 25% after 4 days. In conclusion, the present study shows a transient increase of insulin-like growth factor II/mannose-6-phosphate receptor concentration in hypertrophying diabetic kidneys and in diabetic livers, contemporarily with the previously described increase in kidney insulin-like growth factor I and insulin-like growth factor binding protein content.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Increased kidney and liver insulin-like growth factor II/mannose-6-phosphate receptor concentration in experimental diabetes in rats. 775 75

The salivary glands of mammals synthesize and secrete a number of peptide growth factors that play important roles in cell/tissue homeostasis and embryonic development. Using a radioimmunoassay, insulin, insulin-like growth factor-I (IGF-I) and insulin-like growth factor-II (IGF-II) were detected in saliva from mice. Unlike epidermal growth factor (EGF), there was no sexual dimorphism in the concentrations of the insulin growth factor family. Immunohistochemical localization of IGF-I and IGF-II was confined to the duct cells of both the parotid and the submandibular glands. Reverse transcriptase-polymerase chain reaction amplification of total RNA from parotid and submandibular glands confirmed the presence of all three hormone/growth factor mRNAs in both glands. The levels of insulin and IGF-I were higher in saliva from an animal model for autoimmune type 1 diabetes, the non-obese diabetic (NOD) mouse, than in a second inbred strain, BALB/c. In contrast, the IGF-II levels were decreased relative to the BALB/c strain. With the onset of diabetes in NOD mice, insulin levels declined, while IGF-I and IGF-II levels showed trends toward lower levels of these growth factors when compared with non-diabetic animals. These changes were reflected in the concentrations from parotid and submandibular gland cell lysates.
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PMID:Detection of insulin and insulin-like growth factors I and II in saliva and potential synthesis in the salivary glands of mice. Effects of type 1 diabetes mellitus. 776 95

Amylin is normally secreted in a regulated fashion by the pancreatic beta-cells in parallel with insulin and has been reported to have bone-conserving properties. Type I diabetes mellitus results in a low-turnover osteopenia in the presence of decreased amylin, which is in contrast to type II diabetes where less bone loss, in the presence of high amylin levels, occurs. We investigated the effects of amylin on bone mineral metabolism in normal and diabetic (streptozotocin-induced) rats, in order to ascertain whether amylin would modify the streptozotocin-induced diabetic osteopenia. Ten-week-old male Sprague-Dawley rats were randomized as follows: group A (n = 18) received normal saline; group B (n = 18) received amylin; group C, diabetic rats (n = 23), received normal saline; and group D, diabetic rats (n = 23), received amylin. Amylin (100 pmol/100 g b.w.) was administered by a daily subcutaneous injection. Double calcein-labeled tibiae were removed for histomorphometric analysis followed sacrifice on day 19. Results showed no difference in blood ionized calcium between groups. Blood glucose remained above 600 mg/dl in the diabetic animals and was not affected by the administration of amylin. Serum osteocalcin, insulin-like growth factor-1 (IGF-1), parathyroid hormone (PTH), and 1,25 dihydroxyvitamin D [1,25(OH)2D] were significantly lower in the diabetic rats compared with control group A by day 19. Amylin produced higher levels of serum osteocalcin in group B on day 9 (P < 0.05) compared with controls but returned to control values (group A) by day 19; no such change occurred in the diabetic group.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Amylin increases bone volume but cannot ameliorate diabetic osteopenia. 779 48


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