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)

Impaired wound healing is an enigmatic and debilitating complication of diabetes. A consensus as to the pathogenesis of this disorder has yet to emerge. Recent concepts suggest that IGF-1 is an important regulator of the healing process. The level of this growth factor is reduced in the wound environment of diabetics. We tested the premise that IGF-1 administration may prevent or ameliorate wound healing impairment in streptozotocin (STZ, 55 mg/kg, iv) diabetic rats. IGF-1 (15 micrograms/day) or placebo was infused via mini-osmotic pumps into standardized stainless steel dorsal wound chambers. Wound-related parameters including protein, DNA, hydroxyproline and macrophages were decreased as a function of diabetes. A 14-day treatment with IGF-1 reversed the diabetes effect and increased total hydroxyproline, DNA, protein and macrophage numbers by 48%, 52%, 31% and 40% above vehicle-control values, respectively. The data support the premise that diabetes, related suppression of IGF-1 and/or macrophage function within the wound environment is responsible, at least in part, for the wound healing impairment in this disease state.
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PMID:Insulin-like growth factor-1 reverses diabetes-induced wound healing impairment in rats. 928 75

Besides stimulating GH release, some GH secretagogues also release ACTH and adrenal steroids. Several novel classes of potent GH secretagogues have recently been described, and we have now tested their ability to release corticosterone in conscious normal rats. All analogs that released GH also stimulated corticosterone release to some degree, though the relative effects on GH and corticosterone varied somewhat. The corticosterone responses for some analogs were in the range of those obtained with CRF (2 microg, iv), whereas closely related analogs inactive for GH release failed to release corticosterone. Activation of the hypothalamic-pituitary-adrenal axis with GH release by GHRPs could be a highly diabetogenic combination in susceptible individuals. Therefore, a potent GHRP pentapeptide analog (G7039, 100 microg/day, sc, bid) was given to young obese male Zucker diabetic fatty rats (ZDF, n = 8/group) for 24 days. Other groups received hGH (500 microg/day, sc, bid), recombinant human insulin-like growth factor (rhIGF)-1 (750 microg/day, sc, infusion) or excipient, alone or in combination. Both G7039 and hGH increased weight gain, markedly raised serum glucose (G7039, 542 +/- 37; hGH, 725 +/- 30; excipient, 330 +/- 57 mg/dl) and doubled insulin levels but had opposite effects on serum triglycerides (G7039, 1412 +/- 44; hGH 501 +/- 46; excipient 1058 +/- 73 mg/dl) and fat depot weights. In contrast, treatment with IGF-1, alone or in combination with hGH or G7039, improved the diabetic state and stimulated growth. Thus, both G7039 and hGH treatment stimulated growth in ZDF rats, but greatly worsened diabetes, unless IGF-1 was coadministered. Some of the effects ofG7039 could be explained by GH release, but the effects on blood lipids and body fat were not seen with hGH and may reflect the additional activation of the hypothalamic-pituitary-adrenal axis by the secretagogue. The magnitude of these adverse effects in the ZDF animals suggest that chronic administration of GHRP analogs with cortisol-releasing activity to obese or diabetes-prone individuals warrants careful evaluation.
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PMID:Growth hormone secretagogues stimulate the hypothalamic-pituitary-adrenal axis and are diabetogenic in the Zucker diabetic fatty rat. 932 45

The difficulties of achieving good glycaemic control in insulin-dependent diabetes are due in large part to the inadequacies of subcutaneously administered insulin. In particular, resorption with the long acting form is variable from one subject to another and from one day to another and irregular over time, whereas the action of the rapid acting form is too late and prolonged. The slowness of absorption of the rapid acting form is attributable to the need for hexamer dissociation. The Lilly Laboratories, by inverting the amino acids lysine and proline in positions 28 and 29 in the B chain, have created an insulin (Lispro) which more rapidly dissociates into monomers after injection. The stability of Lispro is good, probably because of its phosphate buffer. In our experience, in conditions simulating use in portable insulin pumps, Lispro proved to be more stable than insulins specially intended for this use. The affinity in vitro was identical to that of insulin for its receptor. The affinity for insulin-like growth factor-I (IGF-I) receptor has been found to be 1.5 times as high as that of fast insulin in some models and comparable in others, and nearly 1,000 times less than that of IGF-1. Studies on in vivo potency and ex vivo cell growth, as well as of tolerance in the animal (mutagenicity, toxicity and carcinogenicity), have not shown a different effect from regular insulin (contrary to results for analogue Asp B10). The pharmacokinetics has shown an earlier and higher insulinaemic peak and a more rapid return to baseline values than regular insulin. On the basis of pharmacokinetic studies in normal subjects and diabetic patients, the characteristics retained by the licensing authorities are onset of action at 15 min, insulinemic peak between 30 and 70 min, and duration of action 2 to 5 h. Some clinical studies have shown a shortened action period of 1 to 3 h as compared to regular insulin and less influence of dose and injection site, notably with a return to normal insulin levels. The time required for normalisation is increased by 1 h if the injection is made in the thigh rather than the abdomen, as compared to 2 to 3 h for conventional insulin. This suggests that Lispro should be administered just before the meal (0 to 15 min). In some patients, an insulin with prolonged action can be added if the interval between injections is prolonged, i.e. always at the evening meal but possibly also at the noon meal. Lispro can be mixed with Umuline NPH or Umuline zinc without any alteration in its pharmacokinetics and potency if the injection is performed immediately. The few studies that have considered glycaemic stability and reproducibility have shown a tendency toward improvement in glycaemic excursions during the day, as measured by MAGE, and in insulinaemia variability expressed in area under the curve, which was reduced by half in the same individual or from one individual to another, with less marked impact on the variability from one day to another of glycaemic excursions. On the whole, Lispro provides faster kinetics, greater stability and possibly better reproducibility than fast insulin. These advantages, if confirmed by clinical experience, should allow an improvement in the comfort and glycaemic stability of diabetic patients.
Diabetes Metab 1997 Sep
PMID:[From the concept of fast acting analogs to the properties of the insulin Lispro]. 941 May 52

The purpose of the study was to investigate the effects of octreotide on the response of counterregulatory hormones to insulin-induced hypoglycaemia in 9 Type 1 diabetic patients without autonomic neuropathy. During an euglycaemic clamp, saline or octreotide (50 mcg) was randomly injected subcutaneously. Patients were then clamped to hypoglycaemic levels (2.5 mmol/l), and hormonal response was evaluated after 30 min of hypoglycaemia. Although octreotide suppressed both GH (0.5 +/- 0.01 vs 9.5 +/- 0.9 ng/ml, p < 0.001) and glucagon (110 +/- 9 vs 165 +/- 10 pg/ml, p < 0.05) responses, it did not affect cortisol, epinephrine, IGF-1 and IGFBP-3 levels. The time required for recovery from hypoglycaemia was longer after octreotide (19.1 +/- 1.2 min vs 14.3 +/- 0.9 min, p < 0.05), and a greater amount of infused glucose was needed to reach normoglycaemia (g 24.6 +/- 1.2 vs 17.7 +/- 1.3, p < 0.05). These findings suggest that administration of octreotide to insulin-treated Type 1 diabetic patients may impair anti-hypoglycaemic counterregulatory mechanisms through suppression of glucagon and GH responses.
Diabetes Metab 1997 Dec
PMID:Effect of octreotide on growth hormone, IGF-I, IGFBP-3, glucagon, cortisol and epinephrine response to insulin-induced hypoglycaemia in insulin-dependent diabetic patients. 949 59

Insulin-like growth factor I (IGF-1) is trophic to sensory, motor and sympathetic neurons. Intrathecal (i.t.) administration of IGF-1 produced analgesic effects when tail flick/withdrawal latency was used as an indicator. This action was blocked by genistein (an inhibitor of tyrosine kinase) but not by atipamezol (an alpha2 adrenoreceptor antagonist), naloxone (an opioid antagonist) or glibenclamide (a blocker of ATP sensitive K+ channels). Induction of diabetes with streptozotocin (STZ, 55 mg/kg, i.v.) impaired the ability of IGF-1 to elevate nociceptive threshold. This phenomenon was not seen in normal animals rendered hyperglycemic with D-glucose (20 mmol in 2.5 ml of saline, i.p.). PCR-based assay revealed that the lumbar region of the spinal cord expresses mRNA transcripts for IGF-1 and its receptor. The rates of expression of both of these transcripts were reduced during diabetes. The above behavioral and biochemical abnormalities induced by the diabetic state were partially restored following replacement therapy with insulin. Overall, our data suggest that a receptor-linked tyrosine kinase mediates the antinociceptive effect of IGF-1. Additionally, the attenuation in the ability of IGF-1 to elevate nociceptive threshold may be a consequence of reduced gene expression of IGF-1 receptor within the spinal cord.
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PMID:Attenuation of IGF-1 antinociceptive action and a reduction in spinal cord gene expression of its receptor in experimental diabetes. 953 75

Plasma IGF-1 was measured in 38 diabetic pregnant women (DPW) and in 12 non diabetic pregnant women (NDPW) during the 1st, 2nd and 3rd trimester of pregnancy. IGF-1 was measured in the cord blood of 24 infants of diabetic mothers (IDDM) and IGF-1 in 11 infants of non diabetic mothers (NIDDM). A progressive and significant (p < 0.0001) increase of IGF-1 values was found throughout the pregnancy both in DPW and NDPW IGF-1 (149 +/- 18 ng/ml vs 181 +/- 14 ng/ml, 184 +/- 17 ng/ml vs 232 +/- 25 ng/ml, 279 +/- 20 ng/ml vs 325 +/- 17 ng/ml). Furthermore IGF-1 decreased significantly soon after delivery in both groups of women. In type 1 diabetic pregnant women IGF-1 values were significantly lower than the controlled non diabetic patients. IGF-1 in the cord blood was significantly higher in IDDM than in NIDDM 86 +/- 7 ng/ml and 62 +/- 7 ng/ml respectively (p < 0.03). In addition, DPW plasma levels IGF-1 were positively correlated with the weight of the placenta (r = 0.233, p < 0.03) and negatively correlated with the diabetes duration (r = 0.412, p < 0.05). No correlations were found between IGF-1 cord blood concentrations and gestational age, birth weight and length, but there was a significant correlation with weight percentile (r = 0.846, p < 0.001). No correlation was found between maternal IGF-1 plasma levels and other parameters like insulin need, weight gain, metabolic control and time of delivery.
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PMID:IGF-1 levels in diabetic pregnant women and their infants. 954 66

A 50-year-old male presented with diabetes mellitus and Cushing's syndrome associated with a large mediastinal mass. The levels of serum cortisol were high (1500-1800 nmol/l) without diurnal variation. Plasma ACTH levels (200-250 ng/l) and urinary excretion of cortisol were also increased. The levels of these hormones did not change in response to stimulation with corticotrophin releasing hormone (CRH) or suppression with high doses of dexamethasone. The patient had an elevated baseline GH level (7.3 mU/l), and the levels of immunoreactive GH-releasing hormone (GHRH) in eight plasma samples were markedly increased (600-1500 ng/l). Circulating levels of IGF-1, chromogranin A and neuropeptide Y (NPY) were also increased. Computer-assisted tomography and octreotide scintigraphy revealed a large mediastinal tumour and metastases in the left supraclavicular fossa. During treatment with octreotide, the baseline GH level was decreased (to 4.4 mU/l), while the GH pulse height was unchanged. Surgical removal of most of the tumour tissue resulted in a further decrease in the baseline serum GH level to a value (1.6 mU/l) about 20% of that before treatment, while the pulse height and mean GH were affected to a lesser extent. Postoperatively, circulating levels of cortisol and IGF-1 decreased, and the patient exhibited clinical improvement. Histological examination showed a neuroendocrine tumour with characteristics consistent with a foregut carcinoid of thymic origin. Immunoreactive GHRH, ACTH and NPY, but not immunoreactive GH, were detected in 80-90% of the tumour cells and the three peptides appeared to be co-localized. In primary culture, cells from this tumour displayed calcium influx in response to GHRH or GH releasing peptide-6 (GHRP-6), while there were not such responses by cells from another carcinoid not producing GHRH, ACTH or NPY. These results demonstrate a rare case of ectopic production of GHRH, ACTH and NPY, and indicate that the tumour cells were responsive to GHRH and GHRP-6 as well as octreotide.
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PMID:Acromegaly and Cushing's syndrome due to ectopic production of GHRH and ACTH by a thymic carcinoid tumour: in vitro responses to GHRH and GHRP-6. 957 39

Poor metabolic control, hemodynamic factors and long duration of diabetes may predispose to the development of diabetic retinopathy. Recently the hypothesis that genetic factors may play certain role in the pathogenesis of diabetic retinopathy has been also proposed. The angiotensin I converting enzyme (ACE) gene has been the main candidate gene predisposing to the development of diabetic retinopathy. One of its polymorphisms--insertion/deletion seems to be particularly associated with long-term diabetic complications. The HLA system genes, TNF-beta gene, IGF-1 gene and PAI-1 gene are the other candidate genes. If there would be strong evidence that genetic factors play certain role in the pathogenesis and progression of diabetic retinopathy, the high risk diabetics could be selected and the adequate prevention could be applied.
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PMID:[Genetic aspects of diabetic retinopathy]. 968 29

Leprechaunism is the most severe form of insulin resistant diabetes and accompanied with growth retardation. Previously, we identified two mutations of insulin receptor (IR) gene in a patient with leprechaunism. In the present study, we assessed the biological actions of IGF-1 in the patient's fibroblasts and investigated short and long term effects of recombinant human IGF-1 (rhIGF-1) treatment on glucose metabolism and growth in the patient. The patient's fibroblasts had normal binding of IGF-1, normal phosphorylation of the beta-subunit of IGF-1 receptor (IGF-1R) and normal incorporation of thymidine in response to IGF-1. The subcutaneous administration of rhIGF-1 at the single dose of 0.4 mg/kg revealed a half life of IGF-1 as short as 90 minutes, and her serum IGFBP-3 level was extremely low. She was treated with rhIGF-1 for about 6 years by both subcutaneous injection (SI) before each meal and continuous subcutaneous infusion (CSI). The administration of rhIGF-1 at the total daily dose of 1.6 mg/kg sustained serum total IGF-1 level within normal range and maintained her growth rate and HbA1c level within nearly normal ranges. Therefore, the treatment with rhIGF-1 was thought to be effective in lowering plasma glucose levels in the patient because these mutant IRs had no dominant negative effects on endogenous IGF-1 Rs. The results suggested that the treatment with a high dose of rhIGF-1 by both SI and CSI is effective for preventing the postnatal growth retardation and normalizing glucose metabolism in patients with genetic form of extremely severe insulin resistant diabetes and that IGF-1 deficient state and partial GH resistance such as the impairment of the production of IGF-1 and IGFBP-3 may contribute to the growth retardation.
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PMID:[Biological and clinical analyses of the mechanism of growth retardation and the effect of recombinant human insulin-like growth factor-1 (rhIGF-1) treatment on glucose metabolism and growth in leprechaunism with severe insulin resistant diabetes]. 1003 18

Familial pituitary tumors are rare. Only 45 cases in 20 families with acromegaly have been reported. A third of the cases (30%) is related to multiple endocrine neoplasia type 1 (MEN 1). We report two cases of acromegaly in one family with pituitary macroadenomas. A 46-year-old woman with elevated serum growth hormone (GH) and insulin-like growth factor (IGF-1) and a failure to supress GH in the glucose tolerance test underwent transsphenoidal surgery 4 years ago. Three years later her 24-year-old son also presented with typical signs of acromegaly. A pituitary macroadenoma was identified by MRT and he also underwent transsphenoidal surgery. There were no symptoms of McCune-Albright syndrome or other forms of endocrine hyperfunction in the two patients. In an attempt to identify the molecular etiology of the tumours DNA was extracted from paraffin fixed tissue from both patients. Exon 7 to 13 of the Gsp-protein and exons 1 to 10 of the menin gene were amplified by PCR. Although Gsp mutations have been identified in 40% of somatotroph tumors, direct sequencing of the PCR products showed no mutations in exons 7 to 13 of Gs alpha. Moreover no mutations were found in exons 1 to 10 of the menin gene. Therefore, molecular causes other than Gsp or menin gene mutations have to be considered as the molecular etiology of acromegaly in this family.
Exp Clin Endocrinol Diabetes 1999
PMID:Acromegaly in a family without a mutation in the menin gene. 1007 64


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