RESUMEN
OBJECTIVES: This study aims to investigate the effects of a combination of soy isoflavones, 8-prenylnaringenin (8-PN), and melatonin in postmenopausal women suffering from moderate-to-severe hot flashes (HFs). METHODS: A multicenter, prospective, open-label study enrolled 44 postmenopausal women suffering from moderate-to-severe HFs (≥ 5 daily or ≥ 35 weekly) to receive 54.4 mg standardized soy isoflavones (including 24.5 mg genistein and 16.3 mg daidzein), 100 µg 8-PN, and 1 mg melatonin once daily for 12 weeks. The primary clinical outcomes included changes in health-related quality of life (HRQoL) scores (Menopause-Specific QoL questionnaire [MENQoL] and Cervantes Scale) and HFs following 4 and 12 weeks of treatment. Other analyses included treatment adherence, acceptability, tolerability, and safety. RESULTS: All of the four domains of MENQoL questionnaire significantly improved at 4 weeks (P < 0.05) and 12 weeks (P < 0.001), affecting significantly the vasomotor, psychosocial, and physical spheres (41.2%, 26.3%, and 25.0%; 12 weeks improvements, respectively). Similarly, in the menopause (39.3%) and psychic (51.7%) domains (both P < 0.05 at 12 weeks), the global score of the Cervantes Scale significantly increased at 4 weeks (18.6%) and 12 weeks (35.4%). Accordingly, moderate-to-severe HFs significantly decreased at 4 weeks compared to baseline (41.7% reduction) and further reduced at 12 weeks (76.5%), including the total number of episodes. CONCLUSIONS: Food supplements containing soy isoflavones, 8-PN, and melatonin showed an early and progressive benefit for reducing clinically significant HFs and for improving HRQoL across all domains, favorably affecting postmenopausal women's overall well-being.
RESUMEN
BACKGROUND: Melatonin is an endogenous substance which plays a key role in sleep induction by reducing sleep onset latency; it has been approved by the European Food Safety Authority as a food supplement for exogenous administration. Oniria® is a food supplement formulated as 1.98 mg of prolonged-release melatonin tablets; it displays a dual dissolution profile in vitro. OBJECTIVES: The main objective of the present study was to evaluate the relative oral bioavailability of Oniria®, in comparison with immediate-release tablets (IRT) with a similar melatonin content as a reference. We also attempted to characterize the circadian rhythm of endogenous melatonin. METHODS: We performed an open-label, cross-over, randomized, phase I clinical study with two sequences and three periods involving 14 healthy volunteers. We characterized the endogenous melatonin circadian profile (period 1) and pharmacokinetics (PK) of both Oniria® and the reference melatonin (periods 2 and 3). RESULTS: Two phases were clearly differentiated in the PK profile of Oniria®. An initial one, from dosing up to 2 h, and a delayed one from 2 to 11 h post-administration. During the initial phase, both melatonin formulations were equivalent, with a Cmax value close to 4000 pg/mL. However, in the delayed phase, Oniria® showed significantly higher melatonin concentrations than the IRT (three times higher at 4-6 h post-administration). Moreover, Oniria® exhibited concentrations above the endogenous melatonin peak of 80 pg/mL for up to 2.5 h versus the reference formulation, potentially suggesting an effect of Oniria®, not only in the induction of sleep, but also in the maintenance. CONCLUSION: Oniria® could be a highly promising food supplement, not only for sleep induction but also for the maintenance of sleep.