Modulation of integrins and filaggrin expression by Propionibacterium acnes extracts on keratinocytes

Abstract

Propionibacterium acnes plays an important role in the pathogenesis of acne and it is established that this bacteria is involved in the induction and maintenance of the inflammatory phase of acne. The aim of our work was to determine if P. acnes extracts could modulate integrins and filaggrin in vitro expression by keratinocytes. Integrins and filaggrin expression was examined using immunohistochemistry technique both on Normal Human Epiderminal Keratinocytes (NHEK) and on deep-frozen sections of normal human skin explants incubated with three different P. acnes extracts. In addition, the expression of filaggrin was investigated on biopsies of acne lesions and by western-blot associated with its precursor profilaggrin. We demonstrated that P. acnes extracts induced beta1 integrin expression significantly on both proliferating keratinocytes and differentiated keratinocytes. In addition, P. acnes induced alpha3, alpha6s and alphaVbeta6 integrin expression and filaggrin expression on differentiated keratinocytes. Finally P. acnes extracts increased filaggrin expression by suprabasal layer of epidermis of explants. Western-blot confirmed that total amount of filaggrin was increased. These results indicate that P. acnes extracts are directly able to modulate the differentiation of keratinocytes suggesting that this bacteria play a role not only in the development of inflammatory acne lesions but also in the formation of the microcomedo.

Cutaneous induction of corticotropin releasing hormone byPropionibacterium acnesextracts

“…Thus, as CRH modifies the differentiation of keratinocytes, we confirm that this bacterium has a spectrum of action, not limited to inflammation but also in the early stages of the formation of acne lesions. 29 This confirms the fundamental role played by this bacterium which can be detected as a local expression in the epidermis induced by the microbial stressor P. acnes.…”

“…26,27 Moreover the genome sequence of P. acnes is known to encode many factors that may have inflammatory potential. 28 But, recently it has also been shown that P. acnes was able to induce keratinocytes proliferation and filaggrin expression by keratinocytes, 29 indicating that this bacterium could play a role not only in the development of inflammation in acne lesions but also in the formation of the comedo.…”

“…[23][24][25][26][27][28][29] In this context, we hypothesized that P. acnes is able to increase CRH expression by keratinocytes, representing a local stress in acne. We thus evaluated the modulation of CRH also described.…”

Hafif ve Orta Şiddetli Akne Vulgaris Tedavisinde Sodyum Sulfasetamidin Etkinliği: Randomize, Karşılaştırmalı Çalışma

“…Yine P. acnes'in mikrokomedonlarda yüksek konsantrasyonda bulunduğu saptanmıştır 7 . Keratinosit proliferasyonunda önemli rolü olan integrinlerden β1, α3, α6s ve ανβ6 integrinlerin de P. acnes ekstreleri tarafından indüklendiği bulunmuştur 8 . Akne patogenezi ile ilgili elde edilen bu bilgiler ışığında P. acnes'in inflamatuvar lezyon oluşumu kadar mikrokomedon oluşum evresinde de önemli role sahip olduğu anlaşılmaktadır.…”

Acne and the epidermal barrier

“…Филаггрин -это ключе-вой белок, участвующий в эпидермальной диффе-ренцировке, способствующий структурной и функ-циональной целостности рогового слоя эпидерми-са. Выявлено, что P. acnes увеличивают экспрессию филаггрина в культивируемых кератиноцитах, а также в эксплантатах кожи человека [16], т.е. при акне увеличивается экспрессия филаггрина в кера-тиноцитах, выстилающих стенку фолликула [17], но пока неясно, являются ли изменения экспрессии филаггрина при акне первичными или вторичными [18].…”