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Insulin unresponsiveness may be associated with a multitude of conditions and reflect diverse etiologies (1). In most cases of chronic insulin resistance it has been possible to demonstrate insulin antagonists in the plasma which have many of the characteristics of antibodies (2-4). The resistance to insulin has usually been attributed to these antibodies, but several cases of insulin resistance associated with increased amounts of insulin in the plasma have been reported (5-8). In these cases tissue unresponsiveness was postulated as the cause for the resistance. In all of these cases circulating insulin could be demonstrated only at a time when the patients were receiving large doses of exogenous insulin, and therefore the insulin in the plasma probably represented injected insulin. We recently have had occasion to study a patient with severe insulin resistance whose plasma contained large amounts of insulin 3 months after her last known injection. Over the ensuing 18 months she had a gradual but complete remission of both diabetes and insulin unresponsiveness. The purpose of this paper is to report studies on this case which indicate that the insulin-like activity in her plasma did, in fact, represent endogenous insulin and that the cause for her insulin resistance was probably due to decreased tissue responsiveness to the hormone. The explanation for her remission is unknown, although there are occasional reports in the literature of spontaneous remission in severe diabetics (9). As far as we know this is the first reported case of insulin-resistant diabetes associated with greatly increased levels of endogenous insulin. METHODSThe rat hemidiaphragm. studies were done as follows.Fed rats weighing between 120 and 170 g were killed by a blow on the head; the diaphragms were removed as rapidly and with as little trauma as possible. Each hemidiaphragm was trimmed, blotted, weighed on a torsion balance and then put into a flask holding 2 ml of incubation medium which contained 0.5 ml of 1,000 mg per 100 ml glucose in Krebs-Ringer bicarbonate buffer (pH 7.4), variable amounts up to 1 ml of dialyzed plasma to be tested, and enough Krebs-Ringer bicarbonate buffer to make the final volume 2 ml.

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BACKGROUND Green tea extract (GTE) has been shown to have antioxidative properties due to its high content of polyphenols and catechin gallates. Previous studies indicated that catechin gallates scavenge free radicals and attenuate the effects of reactive oxidative species (ROS). Cyclophosphamide (CP) produces ROS, which can have adverse effects on development, causing limb, digit, and cranial abnormalities. The current study was performed to determine if exposure to GTE can decrease teratogenic effects induced by CP in CD-1 mice. METHODS From gestation days (GD) 6–13, mated CD-1 mice were dosed with 400 or 800 mg/kg/d GTE; 100, 200, 400, or 800 mg/kg/d GTE + CP; CP alone, or the vehicle. GTE was given by gavage. CP (20 mg/kg) was given by intraperitoneal injection on GD 10. Dams were sacrificed on GD 17, and their litters were examined for adverse effects. RESULTS The highest GTE dose did not effectively attenuate, and in some cases exacerbated the negative effect of CP. GTE alone was also associated with an increased incidence of microblepharia. Conversely, moderate GTE doses (200 &/or 400 mg/kg/d) attenuated the effect of CP on fetal weight and (GTE 200 mg/kg/d) decreased the incidences of certain defects resulting from CP exposure. CONCLUSIONS Exposure of a developing mammal to moderate doses of GTE can modulate the effects of exposure to CP during development, possibly by affecting biotransformation, while a higher GTE dose tended to exacerbate the developmental toxicity of CP. GTE alone appeared to cause an adverse effect on eyelid development.