A Passiflora incarnata extract exerts multi-target effects on selected sleep-related receptors.
Passiflora incarnata extract shows potential interactions with sleep-related receptors, but further research is needed to confirm its effects in humans.
Where it sits
this study against the rest of the melanotan 1 corpusSummary and findings
This study investigated the effects of a standardized Passiflora incarnata extract on sleep-related receptors and neurotransmitter pathways in vitro. The extract inhibited the binding of specific radioligands to adenosine and serotonin receptors. The findings contribute to understanding the neurophysiological mechanisms underlying the traditional use of P. incarnata for sleep promotion.
Abstract
<h4>Ethnopharmacological relevance</h4>Since ancient times, passionflower (Passiflora incarnata L.) is used to treat insomnia, nervousness, anxiety, and other neurological conditions, but the understanding of the underlying neurophysiological processes is largely limited to the involvement of the GABAergic system.<h4>Aim of the study</h4>This work aims to elucidate the mechanism by which P. incarnata modulates selected sleep-promoting receptors and neurotransmitter pathways in the central nervous system.<h4>Materials and methods</h4>We studied the effects of a standardized P. incarnata extract on selected sleep-promoting receptors and neurotransmitters using competitive binding and uptake assays in vitro.<h4>Results</h4>The P. incarnata extract inhibited the binding of [<sup>3</sup>H]-DPCPX to the adenosine A<sub>1</sub>, [<sup>125</sup>I]-ZM 241385 to the adenosine A<sub>2A</sub>, and [<sup>125</sup>I]-LSD to the serotonin 5-HT<sub>2A</sub> receptor, in a concentration-dependent manner, whereas the melatonin MT<sub>1</sub>-and orexin OX<sub>1</sub>-receptors were unaffected. The extract also inhibited [<sup>3</sup>H]-dopamine, [<sup>3</sup>H]-norepinephrine, and [<sup>3</sup>H]-serotonin uptake into rat cortical synaptosomes.<h4>Conclusion</h4>Hitherto undetermined active components of the P. incarnata extract inhibit monoamine uptake and show affinity to the adenosine A<sub>1</sub> and A<sub>2A</sub> and the 5-HT<sub>2A</sub> serotonin receptor. The results of this exploratory study support the longstanding use of P. incarnata to promote sleep.
Background
This paper addresses the pharmacological effects of Passiflora incarnata, traditionally used for insomnia and anxiety. Previous studies have primarily focused on the GABAergic system, but the specific mechanisms of action remain unclear. Understanding these mechanisms is crucial for validating its use in clinical practice.
Methods
The study utilized competitive binding and uptake assays to evaluate the effects of a standardized P. incarnata extract on sleep-promoting receptors. The population involved rat cortical synaptosomes, with no specific n or duration reported. Primary outcomes included binding affinity to various receptors and neurotransmitter uptake inhibition.
Results
The extract inhibited the binding of [3H]-DPCPX, [125I]-ZM 241385, and [125I]-LSD to their respective receptors in a concentration-dependent manner. Specific uptake inhibition was observed for [3H]-dopamine, [3H]-norepinephrine, and [3H]-serotonin in rat cortical synaptosomes, although exact numeric values were not provided.
Interpretation
The findings suggest that P. incarnata has multi-target effects on sleep-related receptors, which aligns with its traditional use. However, the clinical significance of these effects remains uncertain due to the in vitro nature of the study and lack of human data. The absence of effects on melatonin MT1 and orexin OX1 receptors may limit its applicability in sleep disorders.
Key findings
- Inhibited binding of [3H]-DPCPX to adenosine A1 receptors in a concentration-dependent manner.
- Inhibited binding of [125I]-ZM 241385 to adenosine A2A receptors in a concentration-dependent manner.
- Inhibited binding of [125I]-LSD to serotonin 5-HT2A receptors in a concentration-dependent manner.
- Inhibited [3H]-dopamine uptake into rat cortical synaptosomes.
- Inhibited [3H]-norepinephrine uptake into rat cortical synaptosomes.
- Inhibited [3H]-serotonin uptake into rat cortical synaptosomes.
Limitations
- In vitro study, no human data.
- No specific n or duration reported.
- Lack of clinical efficacy evidence.
- No long-term follow-up data.