Claude Blondeau

Ait Abdellah S, et al. Investig Clin Urol. 2025 Jan;66(1):36-46. https://doi.org/10.4111/icu.20240092

Background The benefit of exogenous melatonin is based on its bioavailability, which depends on the galenic form, the route of administration, the dosage, and the individual absorption and rate of hepatic metabolism. Objective The objective of this study is to investigate the bioavailability of melatonin after administration of an oral prolonged-release tablet (PR form) and an immediate-release sublingual spray (IR form). The main metabolite of melatonin, 6-sulfatoxymelatonin (6-SMT), was also measured, which has not been done in previous studies. Its determination is important as an index of the hepatic transformation of melatonin. Methods In this single-center, open-label, randomized, crossover study, 14 healthy male volunteers received one tablet of the PR form (1.9 mg melatonin) or two sprays of the IR form (1 mg melatonin) during two visits separated by a washout period. Blood samples were collected over 7 and 9 h for the IR and PR form, respectively, to determine the main pharmacokinetic parameters. Results The observed kinetics were consistent with those expected for immediate and prolonged-release forms. Pulverization of the spray resulted in an early, high plasma melatonin peak (C_max: 2332 ± 950 pg/mL; T_max: 23.3 ± 6.5 min), whereas tablet intake produced a lower peak (C_max: 1151 ± 565 pg/mL; T_max: 64.2 ± 44.2 min; p < 0.001 for comparison of C_max and T_max) followed by a plasma melatonin plateau and a more prolonged decay over time. Plasma melatonin/6-SMT AUC_0–540/420 ratio was 0.09 for the PR form and 0.16 for the IR form. Both galenic forms were well tolerated. Conclusions The results suggest that the galenic forms containing melatonin assessed in this study are suitable for the treatment of certain sleep disorders such as sleep onset delay and transient nocturnal awakenings for the IR form and insomnia for the PR form. Trial Registry Registration number: NCT04574141.

Background: Increasing evidence suggests the beneficial effects of probiotics in irritable bowel syndrome (IBS), but little is known about how they can impact the gut microbiota. Our objective was to evaluate the effects of a multistrain probiotic on IBS symptoms, gut permeability and gut microbiota in patients with diarrhoea-predominant IBS (IBS-D). Methods: Adults with IBS-D were enrolled in an open-label trial to receive a multistrain probiotic for 4 weeks. Abdominal pain, stool frequency, quality of life, gut permeability, and the luminal and adherent microbiota from colonic biopsies were evaluated before and after supplementation. Results: Probiotics significantly improved symptoms and quality of life, despite having no impact on permeability in the global population. In the population stratified by the response, the diarrhoea responders displayed reduced colonic permeability after supplementation. The luminal and adherent microbiota were specifically altered depending on the patients’ clinical responses regarding pain and diarrhoea. Interestingly, we identified a microbial signature in IBS-D patients that could predict a response or lack of response to supplementation. Conclusions: The multistrain probiotic improved the symptoms of IBS-D patients and induced distinct effects on the gut microbiota according to the patient’s clinical response and initial microbiota composition. Our study further supports the need to develop individualised probiotic-based approaches regarding IBS.

Candida albicans is an opportunistic pathogen that causes mucosal gastrointestinal (GI) candidiasis tightly associated with gut inflammatory status. The emergence of drug resistance, the side effects of currently available antifungals and the high frequency of recurrent candidiasis indicate that new and improved therapeutics are needed. Probiotics have been suggested as a useful alternative for the management of candidiasis. We demonstrated that oral administration of Lactobacillus gasseri LA806 alone or combined with Lactobacillus helveticus LA401 in Candida albicans-infected mice decrease the Candida colonization of the oesophageal and GI tract, highlighting a protective role for these strains in C. albicans colonization. Interestingly, the probiotic combination significantly modulates the composition of gut microbiota towards a protective profile and consequently dampens inflammatory and oxidative status in the colon. Moreover, we showed that L. helveticus LA401 and/or L. gasseri LA806 orient macrophages towards a fungicidal phenotype characterized by a C-type lectin receptors signature composed of Dectin-1 and Mannose receptor. Our findings suggest that the use of the LA401 and LA806 combination might be a promising strategy to manage GI candidiasis and the inflammation it causes by inducing the intrinsic antifungal activities of macrophages. Thus, the probiotic combination is a good candidate for managing GI candidiasis by inducing fungicidal functions in macrophages while preserving the GI integrity by modulating the microbiota and inflammation.

A link between telomere shortening and oxidative stress was found in aging people and patients with cancer or inflammatory diseases. Extracts of Astragalus spp. are known to stimulate telomerase activity, thereby compensating telomere shortening. We characterized a multi-component hydroethanolic root extract (HRE) of Astragalus mongholicus Bunge and assessed its effects on telomeres compared to those of danazol. Astragalosides I to IV, flavonoids, amino acids and sugars were detected in the HRE. Samples of peripheral blood lymphocytes with short telomeres from 18 healthy donors (mean age 63.5 years; range 32–86 years) were exposed to a single dose of 1 µg/mL HRE or danazol for three days. Telomere length and telomerase expression were then measured. Significant elongation of telomeres associated to a less toxicity was observed in lymphocytes from 13/18 donors following HRE treatment (0.54 kb (0.15–2.06 kb)) and in those from 9/18 donors after danazol treatment (0.95 kb (0.06–2.06 kb)). The rate of cells with short telomeres (<3 kb) decreased in lymphocytes from all donors after exposure to either HRE or danazol, telomere elongation being telomerase-dependent. These findings suggest that the HRE could be used for the management of age-related diseases.

Objective: The medicinal plants Rhodiola rosea L. (rhodiola, golden root) and Crocus sativus L. (saffron) have been shown separately to induce significant effects in depression. The objective of this study was to assess a fixed combination of rhodiola and saffron in mild–moderate depression. Methods: In this observational study conducted with general practitioners (GPs), 45 adults (aged 18–85 years) suffering from mild or moderate depression (International Statistical Classification of Diseases and Related Health Problems 10th Revision definition) and reaching a score on the Hamilton Rating Scale for Depression of 8–18 were supplemented with a combination of rhodiola and saffron extracts (one tablet, 154 mg of rhodiola and 15 mg of saffron; recommended dose two tablets per day for 6 weeks). Results: After 6 weeks (D42) of supplementation, Hamilton Rating Scale for Depression scores (primary outcome) decreased significantly by 58%±28.5% (from 13.6±2.3 at D0 to 5.6±3.8 at D42, PConclusion: Results of this observational study performed in primary care suggest that the combination of rhodiola and saffron tested could be useful for the management of mild–moderate depression and improve depressive and anxiety symptoms. A double-blind placebo-controlled study is needed to confirm these results.