Differential effects of clonazepam on declarative memory formation and face recognition.

Benzodiazepines are commonly used drugs to treat anxiety in crime witnesses. These increase GABA inhibitory effects, which impairs aversive memory encoding and consolidation. Eyewitness memory is essential in justice. However, memory is malleable leading to false memories that could cause a selection of an innocent in a lineup. Here, we studied whether a low dose of Clonazepam impairs memory encoding as well as consolidation of faces and narrative of the event. We performed two experiments using a double-blind and between subject design (N = 216). Day 1: subjects watched a crime video and received Clonazepam 0.25 mg (CLZ group) or placebo (PLC group) before (Exp. 1) or after the video (Exp. 2) to assess the effect on encoding and consolidation. One week later, the memory was assessed using a present and absent target lineup and asking for a free recall. Regarding encoding, we found that in the CLZ group memory was impaired in the free recall task, while no differences were found for recognition memory. Regarding consolidation, we did not observe memory measures that were affected by this dose of benzodiazepines. The results suggest that while some aspects of eyewitness memory could be modulated even with low doses of benzodiazepine, others could not be affected. More studies should be performed with higher doses of CLZ similar to those administered in real life. These results are relevant in the judicial field to assess the reliability of the eyewitness elections under the effects of this drug.

Lactoferrin affects in vitro and in vivo fertilization and implantation in rats.

Lactoferrin (LF) is present in the oviduct, reduces in vitro gamete interaction, and affects sperm capacitation parameters in humans. Our aim was to investigate LF actions on further stages of the reproductive process in the Wistar rat model. Motile sperm were obtained from cauda epididymis to assess LF binding by direct immunofluorescence and LF effect on acrosome reaction (AR) using a Coomassie blue staining. After ovarian hyperstimulation of female rats, oocytes were surgically recovered and coincubated with motile sperm and different doses of LF to estimate the in vitro fertilization (IVF) rate. To evaluate the LF effect on pregnancy and embryo implantation, female rats (80 days old) were placed with males and received daily intraperitoneal injections of LF during one complete estrous cycle (pregnancy experiments) or during the first 8 gestational days (implantation experiments). The number of pregnant females and live born pups was recorded after labor. Moreover, the number of implantation sites was registered during the implantation period. LF was able to bind to the sperm head, midpiece, and tail. 10 and 100 µg/ml LF stimulated the AR but reduced the IVF rate. The administration of 100 and 200 mg/kg LF significantly decreased the number of implantation sites and the litter size, whereas 100 mg/kg LF declined the pregnancy rate. The results suggest that LF might interfere with the reproductive process, possibly interfering with gamete interaction or inducing a premature AR; nevertheless, the mechanisms involved are yet to be elucidated.

Lactoferrin levels in cervical fluid from in vitro fertilization (IVF) patients - correlation with IVF parameters.

Since our previous results suggest that lactoferrin (LF) might have roles in the reproductive process and that its levels might change in the female tract as a response to various factors, the aim of this investigation was to assess whether LF levels in cervical secretions correlate with reproductive parameters from in vitro fertilization (IVF) patients. Cervical fluid samples were obtained from 34 women under 40 years old enrolled for assisted reproduction techniques, and LF concentration was measured. The mean total protein concentration in all cervical fluid samples was 842.8 ± 116.9 µg/mL. The mean concentration of LF was 0.73 ± 0.06 ng LF/µg of total proteins. We observed that higher LF levels in cervical fluid correlated with lower IVF rates when all patients were analyzed; this negative correlation was also sustained when only patients ≥35 years were studied. The mean LF concentration in cervical fluid was significantly lower among patients with normal IVF rates than in those with values 50% or less. Using a LF cutoff value of 0.83 ng/µg of total proteins, the study revealed a significant association between the LF levels below 0.83 ng/µg of total proteins and IVF rates above 50%. LF levels in cervical mucus could potentially be used as a marker of fertilization outcome.