Insulin & C-peptide levels in sulfonylurea-induced hypoglycemia: a systematic review

Biochemical Toxicological Study of Insulin Overdose in Rats: A Forensic Perspective

Due to nonspecific pathological changes and the rapid degradation of insulin in postmortem blood samples, the identification of the cause of death during insulin overdose has always been a difficulty in forensic medicine. At present, there is a lack of studies on the toxicological changes and related mechanisms of an insulin overdose, and the specific molecular markers of insulin overdose are still unclear. In this study, an animal model of insulin overdose was established, and 24 SD rats were randomly divided into a control group, insulin overdose group, and a recovery group (n = 8). We detected the biochemical changes and analyzed the toxicological mechanism of an insulin overdose. The results showed that after insulin overdose, the rats developed irregular convulsions, Eclampsia, Opisthotonos, and other symptoms. The levels of glucose, glycogen, and C-peptide in the body decreased significantly, while the levels of lactate, insulin, and glucagon increased significantly. The decrease in plasma K+ was accompanied by the increase in skeletal muscle K+. The PI3K-AKT signaling pathway was significantly activated in skeletal muscle, and the translocation of GLUT4/Na+-K+-ATPase to sarcolemma was significantly increased. Rare glycogenic hepatopathy occurred in the recovery group after insulin overdose. Our study showed that insulin overdose also plays a role in skeletal muscle cells, mainly through the PI3K-Akt signaling pathway. Therefore, the detection of signaling pathway proteins of the skeletal muscle cell membrane GLUT4 and Na+-K+-ATPase has a certain auxiliary diagnostic value for forensic insulin overdose identification. Glycogen detection in the liver and skeletal muscle is important for the diagnosis of insulin overdose, but it still needs to be differentiated from other causes of death. Skeletal muscle has great potential for insulin detection, and the ratio of insulin to the C-peptide (I:C) can determine whether an exogenous insulin overdose is present.

Diabetes management during Ramadan amid Covid-19 pandemic

Management of fasting patients with diabetes during Ramadan has always posed a great challenge on clinicians. This year, Ramadan has coincided with the Covid-19 pandemic which per se can complicate diabetes care. Although patients with diabetes should be generally discouraged from fasting, those who insist to fact during the current Covid-19 pandemic should undergo strict risk assessment and receive thorough education. In patients with type 2 diabetes, administered antidiabetics and their dose should be modified to minimize the risk of hypoglycemia and dehydration. In type 1 diabetic patients, insulin dose and it timing should be precisely calculated based on regular and rigorous blood glucose monitoring. Nonetheless, it would be prudent to generally discourage patients with diabetes form fasting this Ramadan to avoid the risk of life-threatening complications such severe dehydration and ensuing kidney damage.

Is insulin intoxication still the perfect crime? Analysis and interpretation of postmortem insulin: review and perspectives in forensic toxicology

Insulin is an anabolic hormone essential to glucose homeostasis. Insulin therapy, comprising human insulin (HI) or biosynthetic analogs, is critical for the management of type-1 diabetes and many of type-2 diabetes. However, medication error including non-adapted dose and confusion of insulin type, and misuse, such as massive self-administration or with criminal intent, can have lethal consequences. The aim of this paper is to review the state of knowledge of insulin analysis in biological samples and of the interpretation of insulin concentrations in the situation of insulin-related death investigations. Analytic aspects are considered, as quantification can be strongly impacted by methodology. Immunoanalysis, the historical technique, has a prominent role due to its sensitivity and ease of implementation. Recently, liquid chromatography coupled to mass spectrometry has provided indispensable selectivity in forensic contexts, distinguishing HI, analogs, and degradation products. We review the numerous antemortem (dose, associated pathology, injection-to-death interval, etc.) and postmortem parameters (in corpore degradation, in vitro degradation related to hemolysis, etc.) involved in the interpretation of insulin concentration. The interest and limitations of various alternative matrices providing a valuable complement to blood analysis are discussed. Vitreous humor is one of the most interesting, but the low diffusion of insulin in this matrix entails very low concentrations. Injection site analysis is relevant for identifying which type of insulin was administered. Muscle and renal cortex are matrices of particular interest, although additional studies are required. A table containing most case reports of fatal insulin poisoning published, with analytical data, completes this review. A logic diagram is proposed to highlight analytical issues and the main parameters to be considered for the interpretation of blood concentrations. Finally, it remains a challenge to provide reliable biological data and solid interpretation in the context of death related to insulin overdose. However, the progress of analytical tools is making the "perfect crime" ever more difficult to commit.

Suicide attempt by an overdose of sitagliptin, an oral hypoglycemic agent: a case report and a review of the literature

Dipeptidyl peptidase-4 (DPP-4) inhibitors are a newer class of oral hypoglycemic agents for the management of diabetes that elevate the plasma concentration of active glucagon-like peptide-1 via inhibition of DPP-4. They effectively lower not only glycosylated hemoglobin levels, but also fasting and postprandial plasma glucose levels. Patients with diabetes occasionally consume an overdose of oral hypoglycemic agents in suicide attempts: the prevalence of depression is high in patients with diabetes, and depression is a strong risk factor for suicide. We encountered an 86-year-old woman with type 2 diabetes and depression, who was transferred to the emergency room 4h after ingestion of 1,700 mg of the DPP-4 inhibitor sitagliptin (1,700 mg is 17 times greater than the approved maximum dose). Upon arrival, she was fully conscious, plasma glucose was 124 mg/dL, and serum immunoreactive insulin level was 5.81 µU/mL. Thereafter, the plasma concentration of sitagliptin rose to 3,793 nM, which is 4.5 times higher than the value found under regular treatment with the maximum dose. The patient did not suffer from hypoglycemia, suggesting that a single oral overdose of sitagliptin is unlikely to cause hypoglycemia. A literature review of oral anti-diabetic agents revealed that overdose of biguanides is occasionally fatal when immediate intensive care is not provided. In summary, sitagliptin is a good treatment option for diabetic elderly patients or patients with psychiatric disorders who are suicidal and do not require insulin.