-Hydroxycinnamic Acid Mitigates Senescence and Inflammaging in Human Skin Models.

-hydroxycinnamic acid (pHCA) is one of the most abundant naturally occurring hydroxycinnamic acids, a class of chemistries known for their antioxidant properties. In this study, we evaluated the impact of pHCA on different parameters of skin aging in in vitro skin models after HO and UV exposure. These parameters include keratinocyte senescence and differentiation, inflammation, and energy metabolism, as well as the underlying molecular mechanisms.

Integration of transcriptomics and spatial biology analyses reveals Galactomyces ferment filtrate promotes epidermal interconnectivity via induction of keratinocyte differentiation, proliferation and cellular bioenergetics.

Objective: Human skin is the first line of defence from environmental factors such as solar radiation and is susceptible to premature ageing, including a disruption in epidermal differentiation and homeostasis. We evaluated the impact of a Galactomyces Ferment Filtrate (GFF) on epidermal differentiation and response to oxidative stress.

Methods: We used transcriptomics, both spatial and traditional, to assess the impact of GFF on epidermal biology and homeostasis in keratinocytes (primary or immortalized) and in ex vivo skin explant tissue.

Early onset of senescence and imbalanced epidermal homeostasis across the decades in photoexposed human skin: Fingerprints of inflammaging.

Inflammaging is a theory of ageing which purports that low-level chronic inflammation leads to cellular dysfunction and premature ageing of surrounding tissue. Skin is susceptible to inflammaging because it is the first line of defence from the environment, particularly solar radiation. To better understand the impact of ageing and photoexposure on epidermal biology, we performed a system biology-based analysis of photoexposed face and arm, and photoprotected buttock sites, from women between the ages of 20s to 70s.

Aging-Associated Changes in the Adult Human Skin Microbiome and the Host Factors that Affect Skin Microbiome Composition.

Understanding the changes in the skin microbiome and their relationship to host skin factors during aging remains largely unknown. To better understand this phenomenon, we collected samples for metagenomic and host skin factor analyses from the forearm, buttock, and facial skin from 158 Caucasian females aged 20‒24, 30‒34, 40‒44, 50‒54, 60‒64, and 70‒74 years. Metagenomics analysis was performed using 16S ribosomal RNA gene sequencing, whereas host sebocyte gland area, skin lipids, natural moisturizing factors, and antimicrobial peptides measurements were also performed.

Combinations of peptides synergistically activate the regenerative capacity of skin cells in vitro.

Objective: To explore synergistic effects related to skin regeneration, peptides with distinct biological mechanisms of action were evaluated in combination with different skin cell lines in the presence or absence of niacinamide (Nam). Furthermore, the synergistic responses of peptide combinations on global gene expression were compared with the changes that occur with fractional laser resurfacing treatment, a gold standard approach for skin rejuvenation, to further define optimal peptide combinations.

Methods: Microarray profiling was used to characterize the biological responses of peptide combinations (+/- Nam) relative to the individual components in epidermal keratinocyte and dermal fibroblast cell lines.

Metabolic dysfunction in human skin: Restoration of mitochondrial integrity and metabolic output by nicotinamide (niacinamide) in primary dermal fibroblasts from older aged donors.

Alterations in metabolism in skin are accelerated by environmental stressors such as solar radiation, leading to premature aging. The impact of aging on mitochondria is of interest given their critical role for metabolic output and the finding that environmental stressors cause lowered energy output, particularly in fibroblasts where damage accumulates. To better understand these metabolic changes with aging, we performed an in-depth profiling of the expression patterns of dermal genes in face, forearm, and buttock biopsies from females of 20-70 years of age that encode for all subunits comprising complexes I-V of the mitochondrial electron transport chain.

Age-induced and photoinduced changes in gene expression profiles in facial skin of Caucasian females across 6 decades of age.

Background: Intrinsic and extrinsic factors, including ultraviolet irradiation, lead to visible signs of skin aging.

Objective: We evaluated molecular changes occurring in photoexposed and photoprotected skin of white women 20 to 74 years of age, some of whom appeared substantially younger than their chronologic age.

Methods: Histologic and transcriptomics profiling were conducted on skin biopsy samples of photoexposed (face and dorsal forearm) or photoprotected (buttocks) body sites from 158 women.

Understanding metabolic pathways for skin anti-aging.

Global gene expression profiling provides a useful means to identify key aspects of the skin aging process, and provides information to help develop new skin technologies. Important aspects of skin aging that can be addressed include skin hydration, barrier, matrix, pigmentation and antioxidant capacity. Human skin equivalent cultures allow topical application of test compounds, combinations and products to their stratum corneum surface and measurement of predictive biomarkers.

Ontogeny of enhanced decorin levels and distribution within myocardium of failing hearts.

The proteoglycan, decorin, is a regulator of collagen fibril organization and its resulting functional properties. The temporal and spatial expression of decorin during the progression to heart failure is not well understood and may play a significant role in extracellular matrix remodeling. Decorin and types I and III collagen levels were measured in male Spontaneously Hypertensive Heart Failure (SHHF) and control Wistar-Furth rats at 2 and 8 mo, and at congestive heart failure (CHF).