title: Anti-inflammatory properties of low and high doxycycline doses: an in vitro study.
abstract: Doxycycline is used to treat infective diseases because of its broadspectrum efficacy. High dose administration (100 or 200 mg/day) is often responsible for development of bacterial resistances and endogenous flora alterations, whereas low doses (20-40 mg/day) do not alter bacteria susceptibility to antibiotics and exert anti-inflammatory activities. In this study, we wanted to assess the efficacy of both low and high doxycycline doses in modulating IL-8, TNF-α, and IL-6 gene expression in HaCaT cells stimulated with LPS. Three experimental settings were used, differing in the timing of doxycycline treatment in respect to the insult induced by LPS: pretreatment, concomitant, and posttreatment. Low doses were more effective than high doses in modulating gene expression of LPS-induced proinflammatory cytokines (IL-8, TNF-α, and IL-6), when added before (pretreatment) or after (posttreatment) LPS stimulation. This effect was not appreciated when LPS and doxycycline were simultaneously added to cell cultures: in this case high doses were more effective. In conclusion, our in vitro study suggests that low doxycycline doses could be safely used in chronic or acute skin diseases in which the inflammatory process, either constantly in progress or periodically recurring, has to be prevented or controlled.
authors.affiliation: Department of Clinical Medicine and Surgery, Section of Dermatology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Di Caprio
authors.affiliation: Department of Clinical Medicine and Surgery, Section of Dermatology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
authors.forename: Serena
authors.identifier: 0000-0001-9053-1793
authors.initials: S
authors.lastname: Lembo
authors.affiliation: Department of Clinical Medicine and Surgery, Section of Dermatology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Di Costanzo
authors.affiliation: Department of Clinical Medicine and Surgery, Section of Dermatology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
authors.forename: Anna
authors.identifier: 0000-0001-5485-0172
authors.initials: A
authors.lastname: Balato
authors.affiliation: Department of Clinical Medicine and Surgery, Section of Dermatology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Monfrecola
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002460:Cell Line; D004318:Doxycycline / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D012871:Skin Diseases / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D015850:Interleukin-6; D016209:Interleukin-8; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D004318:Doxycycline