Plasma concentration of endothelin-1 in women with cocaine-associated pregnancy complications

Crack abuse during pregnancy: maternal, fetal and neonatal complication

OBJECTIVE

The aim of this study was to assess the effects of crack on pregnancy outcomes.

METHODS

We studied 88 crack user pregnant women in this study. These women were matched to a drug-free group (n = 90) chosen from the population of the same hospital. Maternal outcomes including preeclampsia, placenta abruption, gestational diabetes and preterm labor, and neonatal complication including low birth weight and low Apgar score in 5 min were compared in crack using and drug-free groups. Data were analyzed by SPSS software. Chi-square test and Student's t-test and Relative Risks (RRs) were used in this study.

RESULTS

The results of our study showed that crack abuse during pregnancy was associated with higher rate of preeclampsia p = 0.003 (RR, 1.731; 95% CI, 1.777-2.545), placental abruption p = 0.001 (RR, 2.439; 95% CI, 1.369-4.343), preterm labor p < 0.000 (RR, 3.249; 95% CI, 2.053-5.141) and low birth weight p < 0.000 (RR, 2.179; 95% CI, 1.462-3.247).

CONCLUSIONS

Crack abuse had significant influence on pregnancy outcomes. Crack appears to influence the prevalence of low birth weight, preterm labor, preeclampsia and placental abruption.

Nephrotoxic effects of common and emerging drugs of abuse

The kidneys can be injured in diverse ways by many drugs, both legal and illegal. Novel associations and descriptions of nephrotoxic effects of common and emerging drugs of abuse have appeared over the past several years. Anabolic androgenic steroids, illicitly used by athletes and others for decades to increase muscle mass and decrease body fat, are emerging as podocyte toxins given recent descriptions of severe forms of FSGS in long-term abusers. Synthetic cannabinoids, a new group of compounds with marijuana-like effects, recently became popular as recreational drugs and have been associated with an atypical form of AKI. 3,4-Methylenedioxymethamphetamine, commonly known as ecstasy, is a widely used synthetic recreational drug with mood-enhancing properties and a constellation of toxicities that can result in death. These toxic effects include hyperthermia, hypotonic hyponatremia due to its arginine vasopressin secretagogue-like effects, rhabdomyolysis, and cardiovascular collapse. Cocaine, a serotonin-norepinephrine-dopamine reuptake inhibitor that serves as an illegal stimulant, appetite suppressant, and anesthetic, also causes vasoconstriction and rhabdomyolysis. Recent adulteration of much of the world's supply of cocaine with levamisole, an antihelminthic agent with attributes similar to but distinct from those of cocaine, appears to have spawned a new type of ANCA-associated systemic vasculitis. This review discusses the nephrotoxic effects of these common and emerging drugs of abuse, of which both community and health care providers should become aware given their widespread abuse. Future investigation into pathogenetic mechanisms associated with these drugs is critical and may provide a window into ways to lessen and even prevent the nephrotoxic effects of these drugs of abuse and perhaps allow a deeper understanding of the nephrotoxicities themselves.

A review on renal toxicity profile of common abusive drugs

Drug abuse has become a major social problem of the modern world and majority of these abusive drugs or their metabolites are excreted through the kidneys and, thus, the renal complications of these drugs are very common. Morphine, heroin, cocaine, nicotine and alcohol are the most commonly abused drugs, and their use is associated with various types of renal toxicity. The renal complications include a wide range of glomerular, interstitial and vascular diseases leading to acute or chronic renal failure. The present review discusses the renal toxicity profile and possible mechanisms of commonly abused drugs including morphine, heroin, cocaine, nicotine, caffeine and alcohol.

Spontaneous perinephric haemorrhage and acute renal failure in pregnancy due to cocaine intoxication

Cocaine abuse may contribute to the diverse forms of renal injury. We report a case of a pregnant woman who developed a large subcapsular renal haematoma after cocaine intoxication at 18-week gestation. She stabilized on conservative management and presented again at 29-week gestation with pre-eclampsia, acute renal failure and fetal demise. She required caesarean section delivery and intensive antihypertensive therapy to control severe pre-eclampsia associated with cocaine intoxication. This case is unique in that it is the first report of cocaine intoxication in pregnancy complicated by subcapsular haemorrhage. We discuss the possible mechanisms for the occurrence of this complication.

Chronic nephropathies of cocaine and heroin abuse: a critical review

Renal disease in cocaine and heroin users is associated with the nephrotic syndrome, acute glomerulonephritis, amyloidosis, interstitial nephritis, and rhabdomyolysis. The pathophysiologic basis of cocaine-related renal injury involves renal hemodynamic changes, glomerular matrix synthesis and degradation, and oxidative stress and induction of renal atherogenesis. Heroin is the most commonly abused opiate in the United States. Previous studies identified a spectrum of renal diseases in heroin users. The predominant renal lesion in black heroin users is focal segmental glomerulosclerosis and in white heroin users is membranoproliferative glomerulonephritis. Although the prevalence of heroin use in the United States has increased, the incidence of "heroin nephropathy" has declined. Because reports of heroin nephropathy predated the surveillance of hepatitis C virus and HIV, the varied findings might be related to the spectrum of viral illnesses that are encountered in injection drug users. Socioeconomic conditions, cultural and behavioral practices, or differences in genetic susceptibilities may be more associated with the development of nephropathy in heroin users than the drug's pharmacologic properties. Administration of cocaine in animal models results in nonspecific glomerular, interstitial, and tubular cell lesions, but there is no animal model of heroin-associated renal disease. The heterogeneity of responses that are associated with heroin is not consistent with a single or simple notion of nephropathogenesis. There are no well-designed, prospective, epidemiologic studies to assess the incidence and the prevalence of renal disease in populations of opiate users and to establish the validity of a syndrome such as heroin nephropathy. It is concluded although there is a paucity of evidence to support a heroin-associated nephropathy, the evidence from in vitro cellular and animal studies to support the existence of cocaine-induced renal changes is more convincing.

Cocaine-induced endothelin-1-dependent spasm in rabbit basilar artery in vivo

Although cocaine-induced constriction of cerebral vessels may play an important negative role in the pathogenesis of cocaine-related stroke, the mechanism underlying the vasospasm remains unclear. This study investigated the role of endothelin-1 in mediating the spasm. Intracisternal cocaine infusion (10 microl/h via osmotic pump) into the cisterna magna of rabbits induced time- and concentration-dependent spasm. Maximal spasm was achieved with 100 microM cocaine infusate, and was observed as early as 0.5 days and reached a maximum at 2 days. Coinfusion of 100 microM cocaine with the endothelin receptor antagonist PD145065 (100 microM) prevented the spasm. Cerebral spinal fluid levels of cocaine and benzoylecgonine, a major cocaine metabolite, were below the limit of assay detection. This study demonstrates the novel finding that endothelin-1 mediates cocaine-induced cerebral vasospasm.

Effect of endothelin-1 on intracellular glutathione and lipid peroxide availability and on the secretion of vasoactive substances by human umbilical vein endothelial cells

BACKGROUND

The major pathophysiologic changes observed in preeclampsia suggest that endothelial cell dysfunction plays an important role in this disorder. The pathway mediating endothelial cell layer dysfunction is unknown. The concentration of endothelin-1 (ET-1), a potent mammalian vasoconstrictor peptide produced by the vascular endothelium, has been observed to be significantly increased in preeclampsia. In this study, we determined the in vitro effect of endothelin-1 on glutathione and lipid peroxide levels and on the secretion of vasoactive substances by human umbilical vein endothelial cells (HUVECs).

METHODS

Human umbilical vein endothelial cells were incubated for 24 h in the presence of different concentrations of ET-1 (0-1000 pmol L(-1)), which were shown in an earlier experiment to have no effects on vitality and proliferation rate of HUVECs. The levels of glutathione (GSH) and lipid peroxides (LPO) were measured in endothelial cell lysates. For the measurement of vasoactive substances, levels of nitric oxide (NO), prostacyclin (PGI2) and thromboxane A2 (TXA2) were measured in endothelial cell supernatants.

RESULTS

At lower concentrations (5-50 pmol L(-1)), ET-1 increases the intracellular content of LPO, stimulates the secretion of TXA2, but inhibits the secretion of PGI2 in endothelial cells compared with control cells. At higher concentrations (100-1000 pmol L(-1)), ET-1 increases the intracellular content of GSH, but results in a decrease of LPO, and increase of PGI2, back to control levels. ET-1 has no effect on NO secretion.

CONCLUSION

These findings demonstrate that at concentrations corresponding to values in plasma from preeclamptic women, ET-1 induces oxidative stress and results in altered secretion of vasoactive substances in human endothelial cells. We conclude that ET-1 may participate in the pathway leading to endothelial cell dysfunction seen in preeclampsia.

Fetal effects of cocaine: an updated meta-analysis

BACKGROUND

A very large number of women in the reproductive age group consume cocaine, leading to grave concerns regarding the long term health of millions of children after in utero exposure. The results of controlled studies have been contradictory, leading to confusion, and, possible, misinformation and misperception of teratogenic risk.

OBJECTIVE

To systematically review available data on pregnancy outcome when the mother consumed cocaine.

METHODS

A meta-analysis of all epidemiologic studies based on a priori criteria was conducted. Comparisons of adverse events in subgroups of exposed vs. unexposed children were performed. Analyses were based on several exposure groups: mainly cocaine, cocaine plus polydrug, polydrug but no cocaine, and drug free.

RESULTS

Thirty three studies met our inclusion criteria. For all end points of interest (rates of major malformations, low birth weight, prematurity, placental abruption, premature rupture of membrane [PROM], and mean birth weight, length and head circumference), cocaine-exposed infants had higher risks than children of women not exposed to any drug. However, most of these adverse effects were nullified when cocaine exposed children were compared to children exposed to polydrug but no cocaine. Only the risk of placental abruption and premature rupture of membranes were statistically associated with cocaine use itself.

CONCLUSIONS

Many of the perinatal adverse effects commonly attributed to cocaine may be caused by the multiple confounders that can occur in a cocaine using mother. Only the risk for placental abruption and PROM could be statistically related to cocaine. For other adverse effects, additional studies will be needed to ensure adequate statistical power.

Cocaine: effects of in utero exposure on the fetus and neonate

In North America, an increasing number of babies are prenatally exposed to cocaine, yet the implications of cocaine use during pregnancy are not fully understood. The effects of cocaine are exerted primarily by its influence on aminergic receptors in the central and peripheral nervous systems. Developmental, physiological, and behavioral problems in infants and children are likely outcomes of maternal cocaine abuse, but these findings are confounded by concomitant use of other drugs such as marijuana and cocaine and by factors such as time, dosage, and route of cocaine intake. Different screening options exist for cocaine and its metabolites, including sampling of neonatal urine, hair and meconium need to be considered, as do the sensitivity and the ethical implications of such testing. Clinical management of cocaine-exposed infants requires attention to several issues, including: central nervous system irritation, cardiac anomalies, apnea, and feeding difficulties, as well as infant safety and follow-up postdischarge. Early detection and intervention remain the primary objectives of caring for cocaine-exposed infants.

Salicylate and cocaine: interactive toxicity during chicken mid-embryogenesis

Increased free radical production, due to ischemia and reperfusion, has been postulated as a cause of cocaine's (COC) developmental toxicity. Salicylate reacts with hydroxyl free radicals (*OH) to form stable, quantifiable reaction products, which can be measured with high-pressure liquid chromatography (HPLC). To determine if chicken embryos' brains and hearts were exposed to increased *OH concentrations after injection of COC, an injection of a nontoxic dose of sodium salicylate (NaSAL, 100 mg/kg egg, or 5 mg/egg), followed by 5 injections of COC (13.5 mg/kg or 0.675 mg/egg, every 1.5 h), was administered to eggs containing embryos on the 12th day of embryogenesis (E12). In addition to finding increased *OH concentrations in E12 embryonic hearts and brains, we observed that the developmental toxicity of COC, manifest as vascular disruption (hemorrhage) and lethality, was enhanced by NaSAL injection. These results confirm and extend results of similar experiments performed upon older embryos (E18), and indicate that increased &z.rad;OH concentration in embryonic tissues after COC exposure and toxic interactions of COC and NaSAL can also occur at an earlier stage of development. The results are discussed in light of possible exposure of human fetuses to both COC and salicylates, since COC-abusing pregnant women can be misdiagnosed with pre-eclampsia and aspirin is used to treat this syndrome.

Cocaine and the kidney: a synthesis of pathophysiologic and clinical perspectives

Cocaine abuse has reached epidemic proportions in the United States, and several forms of renal disease have been associated with this widespread use. The hemodynamic actions of cocaine, as well as its effects on matrix synthesis, glomerular inflammation, and glomerulosclerosis, may contribute to renal injury. Cocaine abuse has been associated with various forms of acute renal failure and acid-base and/or electrolyte disorders and may also have a role in the progression of chronic renal failure to end-stage renal disease. In utero exposure to cocaine has been associated with urogenital tract anomalies. Medical management of a hypertensive emergency caused by acute cocaine toxicity requires a multisystem approach, with close monitoring of cardiac, neurological, and renal functions.

Cocaine increases the endothelial release of immunoreactive endothelin and its concentrations in human plasma and urine: reversal by coincubation with sigma-receptor antagonists

BACKGROUND

Cocaine-associated vascular events are not completely explained by adrenergic stimulation. The purposes of this study were to investigate whether vasoconstrictive endothelin-1 is released by cocaine and to elucidate the mechanisms involved.

METHODS AND RESULTS

Endothelin-1 was measured by radioimmunoassay and high-performance liquid chromatography (1) in the supernatant of porcine aortic endothelial cells after treatment with cocaine (10(-7) to 10(-4) mol/L) and a sigma-receptor antagonist, haloperidol (10(-6) mol/L) or ditolylguanidine (10(-5) mol/L) and (2) in plasma and urine of 12 cocaine-intoxicated patients and 13 healthy control subjects. Radioligand binding assays were performed on endothelial membrane preparations. In cell culture, cocaine significantly increased endothelin accumulation above baseline at 3 to 24 hours; endothelin release rates per hour increased dose-dependently, reaching a plateau of 175+/-23% of control at hour 4 to 5. Coincubation of cocaine with haloperidol or ditolylguanidine abolished or reduced cocaine-induced endothelin release. Endothelial membrane preparations specifically and displaceably bound the highly selective sigma-ligand [3H]ditolylguanidine (25x10(-9) mol/L), with 1400 binding sites estimated per cell. Endothelin-1 levels in plasma (22.7+/-5.6 versus 7.3+/-0.8 pmol/L) and urine (41.5+/-10.1 versus 12.7+/-3.8 pmol/L) of cocaine-intoxicated patients were significantly increased compared with control values.

CONCLUSIONS

The data suggest that cocaine increases the endothelin-1 release in vitro and in vivo. The cocaine-induced vasoconstriction/vasospasm may therefore be facilitated by the release of endothelin-1. Cocaine appears to be an exogenous stimulator at endothelial sigma-receptors. The endogenous ligands of this antiopioid system may prove to play a role in vasospastic angina, acute myocardial infarction, and sudden cardiac death.

Pregnancy-induced hypertension: genesis of and response to endothelial injury and the role of endothelin 1

This paper discusses the spectrum of pregnancy-induced hypertension and presents a theory for its etiology. Endothelial injury is the purported precursor to pregnancy-induced hypertensive disorders, and this discussion expands on a possible mechanism by which injury could occur as a result of incomplete trophoblastic invasion. We review endothelin physiology and compare and contrast the evidence surrounding endothelin 1 as a putative mediator of PIH. An approach to treatment utilizing antagonists to the endothelin 1 receptor is introduced.

Hypertension in pregnancy

From the clinical point of view proteinuric hypertension or preeclampsia is the most important form of hypertension in pregnancy and carries the greatest risks for mother and foetus. The syndrome 'preeclampsia' differs from other types of hypertension and its effects on mother and foetus are not clearly benefited by lowering the blood pressure with drugs. The characteristic morphological changes and altered vascular reactivity which develop in preeclampsia commence at about 14 weeks gestation, long before hypertension or proteinuria appear. Many abnormalities in coagulation mechanisms appear in preeclampsia and some may play an important part in pathogenesis. Increased plasminogen activator inhibitor may play a key role. Antihypertensive drugs used during pregnancy may reduce foetal mortality and the incidence of preeclampsia. Calcium supplementation and aspirin may reduce the incidence of preeclampsia in high risk subjects. Heparin and dipyridamole may reduce the risk of preeclampsia in high risk patients with renal disease.