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Rosmarinus officinalis L., a medicinal herb from the labiates family, has been reported to have potential benefit in the treatment and prevention of several diseases. In particular its phenolics have demonstrated protective effects on various types of cancer through several mechanisms. The present study aimed to determine the effects of rosemary phenolic extracts on human cell functions, with particular regard to their anti-proliferative properties in three cell types U937, CaCo-2 and the peripheral blood mononuclear cells (PBMCs). The radical scavenging and Ferric reducing abilities of the extracts have been assessed as well as their cyto-toxicity and effects on cell cycle distribution and apoptosis. About 13 compounds were identified with dominance of rosmarinic acid in the methanolic extract and phenolic diterpens in the ethyl acetate fraction (Carnosol, Carnosic acid and methyl Carnosate). The total polyphenolic content was important in the first extract with 2.589 ± 0.005 g/100 g in gallic acid equivalent compared to 0.763 ± 0.005 g/100 g. The methanolic fraction displayed higher antioxidant activity (DPPHIC50: 0.510 mg/mL and FRAP: 1.714 ± 0.068 mmol Fe2+/g) while ethyl acetate showed pronounced antiproliferative effects (IC50: 14.85 ± 0.20μg/mL and 14.95 ± 2.32 μg/mL respectively for U937 and CaCo-2 cells). The anti-proliferative effect was associated with a cell cycle arrest in S phase for U937 (62% of the population at 5 μg/mL) with a concomitant decrease in G1 and G2/M phases. Tested extracts displayed in addition early apoptotic effects in U937 and late apoptosis in CaCo-2 cells. The obtained data indicate that the identified phenolics are at least partially responsible for the observed cytotoxicity. [ABSTRACT FROM AUTHOR]

Background: Rhamnus alaternus (Rhamnaceae) L. has been traditionally used for treatment of many diseases. Objective: In this study, we determined the antioxidant/free radical scavenger properties, the flavonoid profile and the cytotoxicity of aqueous and methanolic extracts obtained by maceration from Algerian R. alaternus bark, like also of aqueous extract prepared by decoction according to the traditional method. This to estimate the usefulness of the drug traditional preparation and compare it with those made in the laboratory. Materials and Methods: The antioxidant activity of the extracts was evaluated using five different redox-based assays, all involving one redox reaction with the oxidant. High-performance liquid chromatography/diode array detection/electrospray ionization mass spectrometry analysis was used to identify and quantify the flavonoids content. Cytotoxicity on human monocytic leukemia cells (U937) was also carried out. Results: All the extracts tested showed a good antioxidant/free radical scavenger activity and a similar flavonoid fingerprint. However, the methanolic one presented the best antioxidant activity that can be due to the highest flavonoid amount and significantly reduced the proliferation of leukemia cells. The results confirm that the extract prepared by decoction contains efficient antioxidant compounds and this justifies in part the therapeutic and preventive usefulness. Moreover, the methanolic extract exerted excellent cytotoxicity on U937 that could be attributed to kaempferol and rhamnocitrin glycosides. [ABSTRACT FROM AUTHOR]

Background: Polymorphic light eruption (PLE) is the most frequent photodermatosis in Europe with an estimated prevalence of 10 to 20%, particularly in temperate climates. Itching or burning lesions appear only in sun-exposed areas, predominantly on the chest, the arms and forearms within a few hours following exposure. The disease's cause is still unknown, yet studies have suggested that skin microbial elements may play a role in its pathogenesis., Objectives: We investigated in this cohort the skin microbiome of PLE patients upon exposure to ultraviolet radiation (UVR), to assess its role in the onset of PLE lesions., Methods: Forty-one skin swabs have been collected from eleven PLE patients at baseline and following a three-day exposure to UVR and from healthy controls. The collected swabs were analyzed for their microbial composition using a 16S amplicon sequencing approach., Results: The PLE skin showed a dysbalanced microbiome, already at baseline, with significantly reduced microbial diversity and noticeable colonization by bacterial pathogens as Staphylococcus aureus. Upon UVR exposure, the PLE microbiome exhibited a further loss of diversity and decline of beneficial skin commensals. In line with this, we observed that UVR exerted strong antimicrobial effects in vitro against representative skin residents., Conclusions: Taken together, UVR can lead to profound skin microbiome changes, allowing the proliferation of dysbiotic members that can release a variety of elements able to trigger PLE lesions. This is the first study investigating the cutaneous microbiome changes in PLE patients upon UVR, offering new insights into disease pathogenesis, so far unexplored., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Association of Dermatologists.)

Rosmarinus officinalis L., a medicinal herb from the labiates family, has been reported to have potential benefit in the treatment and prevention of several diseases. In particular its phenolics have demonstrated protective effects on various types of cancer through several mechanisms. The present study aimed to determine the effects of rosemary phenolic extracts on human cell functions, with particular regard to their anti-proliferative properties in three cell types U937, CaCo-2 and the peripheral blood mononuclear cells (PBMCs). The radical scavenging and Ferric reducing abilities of the extracts have been assessed as well as their cyto-toxicity and effects on cell cycle distribution and apoptosis. About 13 compounds were identified with dominance of rosmarinic acid in the methanolic extract and phenolic diterpens in the ethyl acetate fraction (Carnosol, Carnosic acid and methyl Carnosate). The total polyphenolic content was important in the first extract with 2.589 ± 0.005 g/100 g in gallic acid equivalent compared to 0.763 ± 0.005 g/100 g. The methanolic fraction displayed higher antioxidant activity (DPPH IC50 : 0.510 mg/mL and FRAP: 1.714 ± 0.068 mmol Fe 2+ /g) while ethyl acetate showed pronounced antiproliferative effects (IC 50 : 14.85 ± 0.20µg/mL and 14.95 ± 2.32 µg/mL respectively for U937 and CaCo-2 cells). The anti-proliferative effect was associated with a cell cycle arrest in S phase for U937 (62% of the population at 5 µg/mL) with a concomitant decrease in G1 and G2/M phases. Tested extracts displayed in addition early apoptotic effects in U937 and late apoptosis in CaCo-2 cells. The obtained data indicate that the identified phenolics are at least partially responsible for the observed cytotoxicity.