Species-level differences between mice and rats in regards to micronucleus induction with the hypothermia-inducing drug haloperidol

[Genotoxicity of psychotropic drugs in experimental and clinical studies]

The analysis of experimental data on the study of the genotoxic activity of psychotropic drugs published over the past 25 years has been carried out. It has been shown that the information describing the genotoxicity of psychotropic drugs is characterized by fragmentation, contradictions, and the conditions for their experimental production often do not meet modern requirements. Conclusions about the presence or absence of genotoxic properties can be made only for 9.6% 94 examined drugs. The need for a large-scale systematic reassessment of the genotoxicity of psychotropic drugs, especially drugs of the first generation, on the basis of modern methodology, including studies of mutagen-modifying activity, has been proven. The expediency of monitoring the genotoxic status of patients receiving psychotropic drugs is emphasized, which should contribute to an adequate assessment of the genotoxic risk of their use and objectification of approaches when choosing a drug for the safe therapy. The urgency of conducting research to determine the role of primary DNA damage in the pathogenesis of mental illnesses has been substantiated.

Evaluation of Duloxetine as Micronuclei Inducer in an Acute and a Subchronic Assay in Mouse

Duloxetine is a widely used antidepressant worldwide. In the present report, we evaluated its capacity to induce micronucleated polychromatic erythrocytes (MNPEs) and micronucleated normochromatic erythrocytes (MNNEs) in mice. Two assays were performed, one with a single chemical administration and the other with daily chemical administration. In the first, we administered the antidepressant once to groups of 5 mice by the intragastric (i.g.) route (2, 20, and 200 mg/kg) and performed the analysis at 24, 48, and 72 h postadministration. A control group administered i.g. distilled water was included in the assay, as well as another treated with the micronuclei-inducing chemical daunorubicin (2.5 mg/kg, injected intraperitoneally (i.p.)). In this assay, we found significant damage induced by duloxetine starting from the first time evaluated, showing the highest MNPE increase at the end of the assay. We observed a saturation effect as well, suggested by a decreasing relative efficiency with respect to each tested dose. In a second assay, we administered the antidepressant i.g. every day for 5 weeks (2, 6, and 12 mg/kg), and micronuclei analysis was performed at the end of each week. In this study, we also found a significant increase in both MNPEs and MNNEs which was clear by the second week of administration. Our results suggest that short-term as well as cumulative damage is produced by duloxetine. Thus, confirmation of the observed genotoxic potential in other models seems advisable, as well as caution when prescribing this antidepressant.

Evaluation of the in vitro cytogenotoxicity profile of antipsychotic drug haloperidol using human peripheral blood lymphocytes

Haloperidol (HLP) is a potent antipsychotic drug that is commonly used for the treatments of schizophrenia and bipolar disorders but has a tendency to cause adverse effects. In the present study, the cyto/genotoxic potential of clinically relevant concentrations of HLP was evaluated in human peripheral blood lymphocytes (HPBLs) as sensitive biomarkers of exposure. HLP was administered as HLP hydrochloride in the final concentrations of 5, 10 and 20 ng/ml for 4 and 24 h period. Cytotoxicity was determined using differential staining of HPBLs with acridine orange and ethidium bromide while chromosomal aberrations, micronucleus and comet assays were applied to estimate the chromosomal and DNA damage after the treatment. The results of the present study indicate that HLP is capable of inducing cyto/genotoxicity in tested cells. Present study has also confirmed the need for further cytogenetic research and regular patient monitoring to minimize the risk of any possible adverse events.

What about temperature? Haloperidol-induced hypotermia

The use of treatment with antipsychotic drugs highlights the difficulty of finding the right balance between the benefit on psychotic symptoms and the risk of the occurrence of adverse reactions. There is a strong genetic and pharmacological evidence supporting the hypothesis that activation of D2 receptors could lead to hypothermia and that the treatment haloperidol is capable of inducing hypothermia apomorfino similarily in laboratory animals. It also seems that, haloperidol is not the only antipsychotic able to determine this type of reaction, as some evidence suggests that other drugs such as reserpine, chlorpromazine would be capable of inducing hypothermia. Finally, while some studies suggest the possible occurrence of haloperidol-induced hypothermia only in laboratory animals, other authors argue that this same reaction can occur in humans as well. In this report, we describe the cases, rarely witnessed in the literature, of three patients in whom the administration of haloperidol caused hypothermia.

Hyperthermia-induced micronucleus formation in a human keratinocyte cell line

Elevated temperature can cause biological effects in vitro and in vivo. Many studies on effects of hypo- and hyperthermia have been conducted, but only few studies systematically investigated the formation of genomic damage in the micronucleus test in human cells in vitro as a consequence of different temperatures. In the present study, HaCaT human keratinocytes were exposed to different temperatures from 37°C to 42°C for 24h in a regular cell culture incubator. Micronucleus frequency as a marker of genomic damage was elevated in a temperature-dependent and statistically significant manner. Apoptosis occurred at temperatures of 39°C or higher. Cell proliferation was unaffected up to 40°C and decreased at 41°C and 42°C. Expression of the heat shock protein Hsp70 was elevated, particularly at temperatures of 40°C and higher. These findings are in agreement with several in vivo studies and some in vitro studies looking at single, specific temperatures, but a systematically investigated temperature-dependent increase of genomic damage in human keratinocytes in vitro is demonstrated for the first time here.