PGC-1s shape epidermal physiology by modulating keratinocyte proliferation and terminal differentiation.

Skin plays central roles in systemic physiology, and it undergoes significant functional changes during aging. Members of the peroxisome proliferator-activated receptor-gamma coactivator (PGC-1) family (PGC-1s) are key regulators of the biology of numerous tissues, yet we know very little about their impact on skin functions. Global gene expression profiling and gene silencing in keratinocytes uncovered that PGC-1s control the expression of metabolic genes as well as that of terminal differentiation programs. Glutamine emerged as a key substrate promoting mitochondrial respiration, keratinocyte proliferation, and the expression of PGC-1s and terminal differentiation programs. Importantly, gene silencing of PGC-1s reduced the thickness of a reconstructed living human epidermal equivalent. Exposure of keratinocytes to a salicylic acid derivative potentiated the expression of PGC-1s and terminal differentiation genes and increased mitochondrial respiration. Overall, our results show that the PGC-1s are essential effectors of epidermal physiology, revealing an axis that could be targeted in skin conditions and aging.

[State of knowledge: couples' experiences of hospitalization due to high-risk pregnancy]. / Etat des connaissances sur l'expérience des couples lors de l'hospitalisation de la femme en raison d'une grossesse à risque élevé.

Taking charge of women with high-risk pregnancy is emerging. In some cases, hospitalization of the pregnant woman might be needed. In nursing sciences, few is known on the couples' experience of the hospitalization, because this event has mostly been explored using a maternal perspective. Some authors however suggest that using a systemic perspective would enhance the comprehension of this phenomenon and guide nursing cares development. In order to clarify the actual understanding of the phenomenon, a literature review has been made. The aim of this article is to present the state of knowledge regarding couples' experience of the women's hospitalization due to high-risk pregnancy. This is compared with the actual nursing practice in the context of practice of the first author of this article. The main themes emerging of this literature review include: giving sense to the antenatal hospitalization, organizing themselves to face danger, taking charge of stress and anxiety through hospitalization and needing each other support. This is followed by a consideration of possible research and nursing practice recommendations, while adopting a systemic constructivist perspective. It takes into account relations between partners and the hospitalization context. Finally, a model presenting the actual nursing practice is discussed.