Diethylene glycol produces nephrotoxic and neurotoxic effects in female rats.

Context: Diethylene glycol (DEG) is an organic compound found in household products but also as a counterfeit solvent in medicines. DEG poisonings are characterized by acute kidney injury (AKI) and by neurological sequelae such as decreased reflexes or face and limb weakness. Previous studies in male rats have demonstrated that neurotoxic effects develop only with the establishment of AKI, but the dose sensitivity of females to DEG toxicity is unknown.

Neurotoxic effects of nephrotoxic compound diethylene glycol.

Context: Diethylene glycol (DEG) is an organic compound found in household products but also as an adulterant in medicines by acting as a counterfeit solvent. DEG poisonings have been characterized predominately by acute kidney injury (AKI), but also by delayed neurological sequelae such as decreased reflexes or face and limb weakness.

Objectives: Characterizing the neurological symptoms of DEG poisoning in a subacute animal model would create a clearer picture of overall toxicity and possibly make mechanistic connections between kidney injury and neuropathy.

Calcium Oxalate Monohydrate is Associated with Endothelial Cell Toxicity But Not with Reactive Oxygen Species Accumulation.

One characteristic of ethylene glycol overdose is a cardiopulmonary syndrome including hypertension and pulmonary edema with pathology indicating damage to the endothelium of heart, lung and brain vessels. The mechanism of the cardiopulmonary toxicity is unknown, but has been linked with accumulation of the metabolite calcium oxalate monohydrate (COM) in the endothelium. These studies have evaluated the hypothesis that COM or the oxalate ion produces endothelial damage in vitro and that damage is linked with induction of reactive oxygen species (ROS).

Human health assessment for long-term oral ingestion of diethylene glycol.

Diethylene glycol (DEG) is an organic chemical that is used mostly as a chemical intermediate and has minor uses as a solvent or antifreeze in consumer products; these minor uses could result in potential human exposure. Potential short and long-term human exposures also occur from misuses. The considerable reporting of DEG misuses as a substitute for other solvents in drug manufacturing and summaries of important events in the history of DEG poisonings are reviewed.

In-vivo evidence of nephrotoxicity and altered hepatic function in rats following administration of diglycolic acid, a metabolite of diethylene glycol.

Context: Diglycolic acid (DGA) is one of the two primary metabolites of diethylene glycol (DEG). DEG is an industrial solvent that has been implicated in mass poisonings resulting from product misuse in the United States and worldwide, with the hallmark toxicity being acute kidney injury, hepatotoxicity, encephalopathy and peripheral neuropathy. Our laboratory has generated in-vitro evidence suggesting that DGA is the metabolite responsible for the proximal tubule necrosis and decreased kidney function observed following DEG ingestion.

Diglycolic acid, the toxic metabolite of diethylene glycol, chelates calcium and produces renal mitochondrial dysfunction in vitro.

Context: Diethylene glycol (DEG) has caused many cases of acute kidney injury and deaths worldwide. Diglycolic acid (DGA) is the metabolite responsible for the renal toxicity, but its toxic mechanism remains unclear.

Objective: To characterize the mitochondrial dysfunction produced from DGA by examining several mitochondrial processes potentially contributing to renal cell toxicity.

Diethylene glycol-induced toxicities show marked threshold dose response in rats.

Diethylene glycol (DEG) exposure poses risks to human health because of widespread industrial use and accidental exposures from contaminated products. To enhance the understanding of the mechanistic role of metabolites in DEG toxicity, this study used a dose response paradigm to determine a rat model that would best mimic DEG exposure in humans. Wistar and Fischer-344 (F-344) rats were treated by oral gavage with 0, 2, 5, or 10g/kg DEG and blood, kidney and liver tissues were collected at 48h.

Quantitation of diethylene glycol and its metabolites by gas chromatography mass spectrometry or ion chromatography mass spectrometry in rat and human biological samples.

The misuse of the commonly used chemical diethylene glycol (DEG) has lead to many poisonings worldwide. Methods were developed for analysis of DEG and its potential metabolites; ethylene glycol, glycolic acid, oxalic acid, diglycolic acid and hydroxyethoxy acetic acid in human urine, serum and cerebrospinal fluid samples, collected following a DEG-associated poisoning in the Republic of Panama during 2006. In addition, methods were developed for rat blood, urine, kidney and liver tissue to support toxicokinetic analysis during the conduct of DEG acute toxicity studies in the rat.

Diglycolic acid inhibits succinate dehydrogenase activity in human proximal tubule cells leading to mitochondrial dysfunction and cell death.

Diethylene glycol (DEG) is a solvent used in consumer products allowing the increased risk for consumer exposure. DEG metabolism produces two primary metabolites, 2-hydroxyethoxyacetic acid (2-HEAA) and diglycolic acid (DGA). DGA has been shown to be the toxic metabolite responsible for the proximal tubule cell necrosis seen in DEG poisoning.

Aluminum citrate blocks toxicity of calcium oxalate crystals by preventing binding with cell membrane phospholipids.

Background/aims: Renal damage from ethylene glycol and primary hyperoxaluria is linked to accumulation of calcium oxalate monohydrate (COM) crystals in the renal proximal tubule (PT). In vitro studies have shown that aluminum citrate (AC), uniquely among citrate salts, blocks COM cytotoxicity to tubular cells. These studies were designed to evaluate the interaction of COM with membrane phospholipids and the ability of AC to reduce COM toxicity by interfering with this interaction.

Oral Reference Dose for ethylene glycol based on oxalate crystal-induced renal tubule degeneration as the critical effect.

Several risk assessments have been conducted for ethylene glycol (EG). These assessments identified the kidney as the primary target organ for chronic effects. None of these assessments have incorporated the robust database of species-specific toxicokinetic and toxicodynamic studies with EG and its metabolites in defining uncertainty factors used in reference value derivation.

Aluminum citrate prevents renal injury from calcium oxalate crystal deposition.

Calcium oxalate monohydrate crystals are responsible for the kidney injury associated with exposure to ethylene glycol or severe hyperoxaluria. Current treatment strategies target the formation of calcium oxalate but not its interaction with kidney tissue. Because aluminum citrate blocks calcium oxalate binding and toxicity in human kidney cells, it may provide a different therapeutic approach to calcium oxalate-induced injury.

Kinetics of fomepizole in pregnant rats.

Context/objectives: Fomepizole has been utilized with remarkable success for ethylene glycol and methanol poisonings in children and adults. However, very little information is available regarding the safe and effective use of fomepizole in pregnancy. The goal of this research was to utilize an animal model to investigate the kinetics of fomepizole in pregnancy.

Kinetics and metabolism of fomepizole in healthy humans.

Context/objective: Fomepizole, a potent inhibitor of alcohol dehydrogenase, has replaced ethanol as antidote for methanol and ethylene glycol intoxications because of a longer duration of action and fewer adverse effects. Prior human studies have indicated that single doses of fomepizole are eliminated by Michaelis-Menten kinetics, but two studies in poisoned patients have suggested that first order elimination occurs after multiple doses. Because of the contrast in fomepizole kinetics among existing studies and the lack of information regarding its metabolism in humans, kinetic and metabolic studies were conducted after single doses and after multiple oral doses in healthy human subjects.

Diglycolic acid is the nephrotoxic metabolite in diethylene glycol poisoning inducing necrosis in human proximal tubule cells in vitro.

Diethylene glycol (DEG), a solvent and chemical intermediate, can produce an acute toxic syndrome, the hallmark of which is acute renal failure due to cortical tubular degeneration and proximal tubular necrosis. DEG is metabolized to two primary metabolites, 2-hydroxyethoxyacetic acid (2-HEAA) and diglycolic acid (DGA), which are believed to be the proximate toxicants. The precise mechanism of toxicity has yet to be elucidated, so these studies were designed to determine which metabolite was responsible for the proximal tubule cell death.

Role of tissue metabolite accumulation in the renal toxicity of diethylene glycol.

Misuse of diethylene glycol (DEG) has led to numerous epidemic poisonings worldwide. DEG produces toxicity because of its metabolism, although the mechanism of its toxicity has not been further defined. The purpose of this study was to investigate the accumulation of specific metabolites in blood and target organ tissues and to determine the relationship between tissue accumulation of metabolites and the resulting toxicity.

Involvement of urinary proteins in the rat strain difference in sensitivity to ethylene glycol-induced renal toxicity.

Ethylene glycol (EG) exposure is a common model for kidney stones, because animals accumulate calcium oxalate monohydrate (COM) in kidneys. Wistar rats are more sensitive to EG than Fischer 344 (F344) rats, with greater COM deposition in kidneys. The mechanisms by which COM accumulates differently among strains are poorly understood.

Inhibition of metabolism of diethylene glycol prevents target organ toxicity in rats.

Diethylene glycol (DEG) is an industrial chemical, the misuse of which has led to numerous epidemic poisonings worldwide. The mechanism of its toxicity has not been defined as to the precise relationship between the metabolism of DEG and target organ toxicity. The purpose of this study was to investigate the mechanism for the acute toxicity of DEG, and the effect of the alcohol dehydrogenase inhibitor 4-methylpyrazole (fomepizole), by determining the relationship between accumulation of DEG or its metabolites and the resulting kidney and liver toxicity.

Renal toxicity of ethylene glycol results from internalization of calcium oxalate crystals by proximal tubule cells.

Ethylene glycol exposure can lead to the development of renal failure due to the metabolic formation of calcium oxalate monohydrate (COM) crystals. The renal damage is closely linked to the degree of COM accumulation in the kidney and most likely results from a COM-induced injury to proximal tubule (PT) cells. The present studies have measured the binding and internalization of COM by primary cultures of normal PT cells from humans and from Wistar and Fischer-344 rats in order to examine the roles of these uptake processes in the resulting cytotoxicity.

Relationship between serum glycolate and falsely elevated lactate in severe ethylene glycol poisoning.

In the setting of ethylene glycol (EG) poisoning, a falsely elevated serum lactate concentration is suggested to be an assay cross-reaction with glycolate, but a concentration-dependent relationship has never been identified. We correlate serum lactate and glycolate concentrations in a case of severe EG poisoning. Serial EG [by gas chromatography (GC)], glycolate (derivatized to methyl glycolate, analysis by GC), and lactate (both enzymatic spectrophotometry and GC) concentrations were correlated at five time points.

Strain differences in urinary factors that promote calcium oxalate crystal formation in the kidneys of ethylene glycol-treated rats.

Ethylene glycol (EG)-induced hyperoxaluria is the most commonly employed experimental regimen as an animal model of calcium oxalate (CaOx) stone formation. The variant sensitivity to CaOx among different rat strains has not been fully explored, although the Wistar rat is known to accumulate more CaOx in kidney tissue after low-dose EG exposure than in the Fischer 344 (F344) rats. Supersaturation of CaOx in tubular fluid contributes to the amount of CaOx crystal formation in the kidney.