Circulating insulin-like growth factor I concentrations in clinically severe obese patients with and without NIDDM in response to weight loss

Earlier studies have demonstrated decreased levels of circulating Insulin-Like Growth Factor-I (IGF-I) in patients with NIDDM and IDDM (Yde 1969; Rieu and Binoux 1985), with a return to normal in those diabetics who achieve improved metabolic control (Rieu and Binoux 1985; Ameil, Sherwin, Hintz, Gertner, Press and Tamborlane 1984) following insulin therapy. One method of improving metabolic control in clinically severe obese NIDDM patients is the gastric bypass procedure (GBP). This study revealed a significant decrease in serum IGF-I concentrations in clinically severe obese patients with NIDDM (obese NIDDM) (105 ng/dl +/- 11; n = 29) as compared with clinically severe obese patients with normal glucose tolerances (obese control) (143 +/- 11; n = 21) and lean controls (177 +/- 14; n = 19) (p < 0.001). Following a GBP, IGF-I levels increased in the NIDDM group (142 ng/dl +/- 13.0; n = 20) to the extent that no significant difference was seen between postoperative NIDDM, obese controls, and lean controls. Postoperative IGF-I levels in the obese controls (151 +/- 14; n = 9) revealed no difference from preoperative levels. Postoperative obese NIDDM and obese control had a 28% and 29% decrease, respectively, in weight, with no difference between the groups in respect to Body Mass Indices. The NIDDM postoperative group revealed reductions in levels of HbA1C, insulin, and glucose concurrent with elevations in IGF-I when compared with controls. We conclude that improvement in glucose control led to the increase in IGF-I levels.

Is type II diabetes mellitus (NIDDM) a surgical disease?

Since February 1, 1980, 515 morbidly obese patients have undergone the Greenville gastric bypass (GGB) operation. Of these, 212 (41.2%) were euglycemic, 288 (55.9%) were either diabetic or had glucose intolerance, and 15 (2.9%) were unable to complete the evaluation. After the operation, only 30 (5.8%) patients remained diabetic (and 20 of these improved), 457 (88.7%) became and have remained euglycemic, and inadequate data prevented classification of the other 28 (5.4%). The patients who failed to return to normal glucose values were older and their diabetes was of longer duration than those who did. The effect of the GGB was not only limited to the correction of abnormal glucose levels. The GGB also corrected the abnormal levels of fasting insulin and glycosylated hemoglobin in a cohort of 52 consecutive severely obese patients with non-insulin-dependent diabetes. The GGB effectively controls weight. If morbid obesity is defined as 100 pounds over ideal body weight, 89% of the patients are no longer "morbidly" obese within 2 years. In most patients, the control of the weight has been well maintained during the 11 years of follow-up; most of the upward creep in weight of 20.8% between 24 and 132 months was from the 49 (9.5%) patients who had staple line breakdowns between the large and small gastric pouches. Non-insulin-dependent diabetes, previously considered a chronic unrelenting disease, can be controlled in the severely obese by the gastric bypass. Whether the correction of glucose metabolism affects the complications of diabetes is unknown. Whether the gastric bypass should be considered for patients with advanced non-insulin-dependent diabetes but who are not severely obese deserves consideration. The GGB has an unacceptably high rate of staple line failure. Accordingly, the authors have recently changed their procedure to one that divides the stomach rather than partitions it with staples.

Influence of obesity, impaired glucose tolerance, and NIDDM on LDL structure and composition. Possible link between hyperinsulinemia and atherosclerosis

The possible causes of the enhanced risk for coronary heart disease (CHD) were examined in morbidly obese women with normoglycemia, impaired glucose tolerance (IGT), and non-insulin-dependent diabetes mellitus (NIDDM) before and after gastric bypass surgery. Compared with age-matched lean women, plasma lipid and apolipoprotein concentrations of the obese women before surgery favored atherogenesis. The risk for CHD may further be exacerbated in the IGT and NIDDM groups by the prevalence of smaller and denser low-density-lipoprotein (LDL) particles. LDL size correlated negatively with plasma insulin levels independent of triglyceride levels, age, or body mass index (BMI). After surgery, BMI, plasma insulin, and triglyceride levels decreased, but LDL size increased, and LDL density decreased. Neither cholesterol nor LDL cholesterol levels were affected after surgery, but high-density-lipoprotein cholesterol was increased in all patients after surgery. Although the mechanisms underlying the changes in the properties of LDL could not be determined from this study, these changes appear to be of benefit in reducing CHD risk in these patients.

IGF-II receptors and IGF-II-stimulated glucose transport in human fat cells

Insulin-like growth factor II (IGF-II) receptors have been described in rat but not in human adipocytes. In both species, IGF-II has been reported to stimulate glucose transport by interacting with the insulin receptor. In this study, we have unequivocally demonstrated the presence of IGF-II receptors in human adipocytes. 125I-labeled IGF-II specifically binds to intact adipocytes, membranes, and lectin-purified detergent solubilized extracts. Through the use of 0.5 mM disuccinimidyl suberate, 125I-IGF-II is cross-linked to a 260-kDa protein that is identified as the IGF-II receptor by displacement experiments with unlabeled IGF-II, IGF-I, and insulin and either by immunoprecipitation or by Western blot analysis with mannose 6-phosphate receptor antibodies. The concentrations of IGF-II required for half-maximal and maximal stimulation of glucose transport in human adipocytes are 35 and 100 times more than that of insulin. The possibility of IGF-II stimulating glucose transport by interacting predominantly with the insulin receptor is suggested by the following: 1) the concentration of IGF-II that inhibits half of insulin binding is only 20 times more than that of insulin; 2) the lack of an additive effect of IGF-II and insulin for maximal stimulation of glucose transport; 3) the ability of monoclonal insulin receptor antibodies to decrease glucose transport stimulated by submaximal concentrations of both IGF-II and insulin; and 4) the ability of IGF-II to stimulate insulin receptor autophosphorylation albeit at a reduced potency when compared with insulin.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis of pancreatic allograft rejection by measurement of urinary radioimmunoreactive insulin

The accurate, early, and sensitive diagnosis of pancreatic allograft rejection is one of the major problems in clinical pancreas transplantation today. Pancreaticocystotomy is a popular technique for pancreas transplantation that permits simple and frequent urinary chemistry examinations. In this experiment, 20 mongrel dogs with a bladder-drained pancreatic transplant had serial monitoring of urinary amylase (UA) and urinary insulin (UI). The mean UI in the nonrejection state was 9.6 +/- 12 mIU/L. In eight dogs varying degrees of rejection were documented by histopathology. All three animals having severe acute rejection had high levels of IU (all greater than 300-800 mIU/L). Of the five animals with mild-to-moderate rejection, all had significant UI elevations to greater than 100 mIU/L but none had elevations above 200 mIU/L (P less than 0.05 for all groups). Ten animals were treated with prednisone, Imuran, and cyclosporine (CsA), and five of these dogs had good graft function for greater than 14 days, during which the mean UI was extremely low (11 +/- 6.4 mIU/L, P less than 0.05). These values were not significantly different from the 0-14-day values for three pancreas autotransplants with bladder drainage (8.9 +/- 7.2 mIU/L, P less than 0.05). All rejections were preceded by significant rises of UI occurring two to five days prior to rejection. In seven animals, early graft dysfunction (1-4 days) developed, with total graft necrosis by five days. This graft injury was presumably caused by preservation damage or early vascular thrombosis and was associated with early (1-4 days) marked elevations of the UI (greater than 300 mIU/L). None of the animals with grafts surviving to rejection at seven days or more had these early severe elevations, and thus these early UI rises are pathognomonic of graft damage. In contrast, UA and lipase showed inconsistent association with rejection or early damage, although falls in UA generally occurred at or following the time of rejection. Marked daily variations in UA measurements were the most difficult aspect of UA monitoring. Serial electromagnetic flow probe studies of blood flow to the pancreas graft showed a good correlation between loss of blood flow and rises in UI associated with early graft injury. These results suggested that the UI assay gives a sensitive, early, accurate, and specific differential prediction of pancreas graft dysfunction. Specifically, the UI assay appears to be of value not only in the early differential diagnosis of graft injury and graft rejection, but also in the assessment of the severity of rejection.(ABSTRACT TRUNCATED AT 400 WORDS)

Acid Catalyzed Rearrangements of Conjugated Cyclopropyl and Epoxy Ketones

A series of spiro[n.2]alkan-2-ones and their 6 and 7 oxa derivatives were subjected to acid catalysis. In the former series, products arising from hydroxyl(cyclopropyl)carbinyl cations are observed, while in the latter series epoxide oxygen protonation appears to be the dominant reaction pathway. A novel oxavinylcyclopropane rearrangement is reported.