Behavioral pharmacological properties after recovery from the loss of righting reflex induced by benzodiazepine receptor agonists in mice

Comparative study of royal jelly, propolis, and photobiomodulation therapies in 5-fluorouracil-related oral mucositis in rats

PURPOSE

This study aimed to evaluate the effects and mechanisms of action of royal jelly (RJ) and propolis compared to photobiomodulation therapy (PBMT) in an animal model of 5-fluorouracil-related oral mucositis (OM).

METHODS

Seventy-two male Wistar rats were randomly allocated to four groups (n = 18 each): control (no treatment), PBMT (intraoral laser, 6 J/cm²), RJ, and propolis. On days 0 and 2, the animals received an injection of 5-fluorouracil (5-FU). The buccal mucosa was scratched (days 3 and 4) and the treatments were initiated on day 5. Six animals of each group were euthanized on days 8, 10, and 14. Phytochemical analysis (thin-layer chromatography, TLC) and clinical, histopathological, and immunohistochemical analysis of pS6, pAKT, and NF-κB were performed, and oxidative stress markers were also investigated.

RESULTS

TLC revealed the presence of large amounts of sucrose (Rf 0.34) in RJ and of flavonoids in propolis. Lower clinical OM scores were observed on day 8, and improved morphological data were observed on day 10 in the PBMT, RJ, and propolis groups (p < 0.05). On day 8, immunoexpression of pS6, pAKT, and NF-κB was increased compared to control. On day 14, reduced glutathione (GSH) antioxidant levels were increased in the propolis group compared to control (p < 0.05).

CONCLUSIONS

Our results showed that RJ and propolis, as well as PBMT, are effective in the treatment of OM. Considering that some patients who develop OM do not have access to PBMT, the present study demonstrated that topical application of RJ and propolis may be an important alternative for the treatment of OM.

Desensitization of GABAergic receptors as a mechanism of zolpidem-induced somnambulism

Sleepwalking is a frequently reported side effect of zolpidem which is a short-acting hypnotic drug potentiating activity of GABA(A) receptors. Paradoxically, the most commonly used medications for somnambulism are benzodiazepines, especially clonazepam, which also potentiate activity of GABA(A) receptors. It is proposed that zolpidem-induced sleepwalking can be explained by the desensitization of GABAergic receptors located on serotonergic neurons. According to the proposed model, the delay between desensitization of GABA receptors and a compensatory decrease in serotonin release constitutes the time window for parasomnias. The occurrence of sleepwalking depends on individual differences in receptor desensitization, autoregulation of serotonin release and drug pharmacokinetics. The proposed mechanism of interaction between GABAergic and serotonergic systems can be also relevant for zolpidem abuse and zolpidem-induced hallucinations. It is therefore suggested that special care should be taken when zolpidem is used in patients taking at the same time selective serotonin reuptake inhibitors.