Innate immunity activation of sebocyte cells by living bacteria. Evidence of a potential immunosuppressive effect of DHT.

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Acne is a skin pathology targeting the pilosebaceous unit…sebum hypersecretion and bacterial infection. We studied the effects of living bacteria on the induction of an innate immune response in a sebocyte cell line.

Pharmacological effects of anti-androgens and other compounds in an androgen-sensitive sebocyte cell line.

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We analysed the activity of reference anti-androgens (Finasteride, Dutasteride, Cyproterone acetate), at the level of their potential targets (5-alpha-reductase, AR translocation, induced transcripts) and in a functional lipid accumulation assay. We also evaluated this androgen-induced lipid accumulation assay as a potential pharmacological tool to detect potential inhibitors from both androgenic and non-androgenic origins.

Androgens activate lipogenesis through an AKT-independent mTOR pathway stimulation and a limitation of autophagy in an androgen-sensitive sebocyte cell line.

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Androgens are key regulators of sebaceous function... A link between mTOR and androgen signaling has previously been reported...as well as a link between these processes and lipid synthesis...Here we aimed at confirming that DHT-induced lipid synthesis/accumulation is at least in part dependent on mTOR activation in the SEBO662AR cell line and that the autophagic process is consequently modified by the androgenic treatment.
lipid

Acne vulgaris: physiopathology and cell mechanisms

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Acne Vulgaris is a chronic inflammatory pathology located in the region of the pilosebaceous follicle. It occurs following a high production of sebum linked to hormonal (androgynous) or environmental (pollution) malfunctioning and to the colonization of the pilosebaceous follicle by certain bacteria (P. acnes). QIMA Life Sciences has developed a panel of innovative assays to discover and evaluate compounds for the treatment of acne.

Physiology and functions of the sebaceous gland

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The sebaceous gland is an organ located in the dermis. Its role is to synthesise and secrete sebum which is a component of the hydrolipidic film. The purpose of sebum is to protect the skin from external aggression and dehydration. Sebum also maintains the suppleness of the skin and hair.

Androgens induce sebaceous differentiation in sebocyte cells expressing a stable functional androgen receptor

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In order to study the impact of active androgens in sebocytes, we constructed a stable human sebocyte cell line derived from SEBO662 [17] constitutively expressing a fully functional AR. In these SEBO662 AR+ cells, dihydrotestosterone (DHT) induced AR nuclear translocation and the strong modulation of a set of transcripts (RASD1, GREB1...) known to be androgen-sensitive in other androgenic cells and tissues.

Immortalized sebocytes SEBO662 can spontaneously differentiate into a sebaceous-like phenotype when cultured as a 3D epithelium

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SEBO662 multilayers spontaneously differentiate into a sebaceous-like structure as shown by the strong polarized expression of the late sebaceous marker EMA, the overexpression of some lipogenic markers and lipid production on the upper side of the epithelium.