Polyphenol-rich apple extract inhibits dexamethasone-induced sebaceous lipids production by regulating SREBP1 expression.

Sebum production and excretion is a primary function of the sebaceous glands, but abnormally increased sebum production is a major cause of acne vulgaris. To identify a new candidate that regulates sebum production, we investigated the possible inhibitory effects of apple polyphenols (APP) purified from unripe apples on primary cultured human sebocytes and in patients with acne vulgaris. Dexamethasone (Dex) increased lipid synthesis and expression of the sterol response element-binding protein 1 (SREBP 1) and its target enzymes, acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), in the sebocytes.

A study of facial wrinkles improvement effect of veratric acid from cauliflower mushroom through photo-protective mechanisms against UVB irradiation.

Solar ultraviolet (UV) irradiation is a primary cause of premature skin aging that is closely associated with the degradation of collagens caused by up-regulation of matrix metalloproteinases (MMPs) or a decrease in collagen synthesis. The phenolic veratric acid (VA, 3,4-dimethoxybenzoic acid) is one of the major benzoic acid derivatives from fruits, vegetables and medicinal mushrooms. VA has been reported to have anti-inflammatory, anti-oxidant and photo-protective effects.

Abietic acid inhibits UVB-induced MMP-1 expression in human dermal fibroblast cells through PPARα/γ dual activation.

Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors and consist of three isotypes: PPARα, PPARβ/δ and PPARγ. PPARs are expressed in various cell types in the skin, including keratinocytes, fibroblasts and infiltrating immune cells. Thus, these receptors are highly studied in dermato-endocrine research, and their ligands are targets for the treatment of various skin disorders, such as photoageing and chronological ageing of skin.

Paradoxical benefits of psychological stress in inflammatory dermatoses models are glucocorticoid mediated.

Acute psychological stress (PS) mobilizes metabolic responses that are of immediate benefit to the host, but the current medical paradigm holds that PS exacerbates systemic and cutaneous inflammatory disorders. Although the adverse consequences of PS are usually attributed to neuroimmune mechanisms, PS also stimulates an increase in endogenous glucocorticoids (GCs) that compromises permeability barrier homeostasis, stratum corneum cohesion, wound healing, and epidermal innate immunity in normal skin. Yet, if such PS-induced increases in GC were uniformly harmful, natural selection should have eliminated this component of the stress response.

Local blockade of glucocorticoid activation reverses stress- and glucocorticoid-induced delays in cutaneous wound healing.

Stress slows cutaneous wound healing (WH) in an endogenous glucocorticoid (GC)-dependent fashion. We investigated whether stress/GC-induced delays in WH require further intracutaneous activation of endogenous GC; and whether blockade or down-regulation of peripheral activation normalizes WH in the face of stress. Delayed WH in our motion-restricted murine model of stress could be attributed to elevated systemic GC, because blockade of GC production (using corticotropin-releasing factor inhibitor, antalarmin), or of peripheral binding to the GC receptor [GCr], with an antagonist, Ru-486, normalized WH.

Antagonist effects of veratric acid against UVB-induced cell damages.

Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents.

Expression of epidermal CAMP changes in parallel with permeability barrier status.

Two critical defensive functions of the outer epidermis, the permeability barrier and antimicrobial defense, share certain structural and biochemical features. Moreover, three antimicrobial peptides (AMPs), i.e.

Psychological stress regulates antimicrobial peptide expression by both glucocorticoid and β-adrenergic mechanisms.

Psychological stress (PS) exerts well-known negative consequences for permeability barrier function in humans and mice, and deterioration of barrier function appears to be attributable largely to excess production of endogenous glucocorticoids (GC). More recently, PS has been shown to compromise antimicrobial defense, also by GC-dependent mechanisms. We assessed here changes in a third antimicrobial peptide (AMP); i.

Anti-ageing effects of a new synthetic sphingolipid (K6EAA-L12) on aged murine skin.

Recently, we reported on the anti-ageing effects of K6PC-5. This compound induced keratinocyte differentiation and fibroblast proliferation by increasing sphingosine-1 phosphate synthesis. We performed this study to confirm the anti-ageing effects of new synthetic products (the K6EAA series) derived from K6PC-5 through an amino group induction.

Inhibition of skin inflammation and atopic dermatitis by topical application of a novel ceramide derivative, K112PC-5, in mice.

PC-9S (N-Ethanol-2-mirystyl-3-oxo-stearamide) is a synthetic ceramide and has been known to be effective in atopic and psoriatic patients. K112PC-5 (2-Acetyl-N-(1,3-dihydroxyisopropyl)-tetradecanamide) is a novel ceramide derivative of PC-9S. In the present study, we examined the effect of K112PC-5 on macrophage and T lymphocyte function in primary macrophages and splenocytes, respectively, as well as the effect of topical application of K112PC-5 on skin inflammation and atopic dermatitis (AD) in mouse models.

Inhibition of atopic dermatitis-like skin lesions by topical application of a novel ceramide derivative, K6PC-9p, in NC/Nga mice.

Atopic dermatitis (AD) is a chronic inflammatory skin disease that commonly begins in childhood. K6PC-9p (N-(Ethyl dihydrogenphosphate)-2-hexyl-3-oxo-decanamide) is a synthetic ceramide derivative of PC-9S (N-Ethanol-2-mirystyl-3-oxo-staramide), which was known to be effective in atopic patients. In this study, we examined the effect of topical application of K6PC-9p on skin inflammation and AD-like skin lesions in mouse models.

K6PC-5, a sphingosine kinase activator, induces anti-aging effects in intrinsically aged skin through intracellular Ca2+ signaling.

Background: Sphingosine-1-phosphate (S1P), a bioactive sphingolipid metabolite, regulates multiple cellular responses such as Ca(2+) signaling, growth, survival, and differentiation. Because sphingosine kinase (SK) is the enzyme directly responsible for the production of S1P, many factors have been identified that regulate its activity and subsequent S1P levels. To date, there are no reports to demonstrate a chemically induced, direct activation of SK.

K6PC-5, a direct activator of sphingosine kinase 1, promotes epidermal differentiation through intracellular Ca2+ signaling.

Sphingosine-1-phosphate (S1P), a bioactive sphingolipid metabolite, regulates multiple cellular responses such as Ca(2+) signaling, growth, survival, and differentiation. Because sphingosine kinase (SphK) is the enzyme directly responsible for production of S1P, many factors have been identified that regulate its activity and subsequent S1P levels. Here we synthesized a previously unidentified SphK activator, K6PC-5, and have studied its effects on intracellular Ca(2+) signaling in HaCaT cells and epidermal differentiation in murine skin.

K6PC-5, a novel sphingosine kinase activator, improves long-term ultraviolet light-exposed aged murine skin.

Sphingosine-1-phosphate (S1P), which is formed by phosphorylation of sphingosine through a process catalysed by sphingosine kinase (SK), is a multifunctional mediator of a variety of cellular responses including proliferation, differentiation, motility, and survival. K6PC-5, which was recently synthesized as a novel SK activator, is expected to increase S1P levels. Indeed studies have already demonstrated that K6PC-5 exhibits anti-aging effects on intrinsic aged murine skin by increasing fibroblasts, collagen synthesis, dermal thickness, and epidermal differentiation.

Mite and cockroach allergens activate protease-activated receptor 2 and delay epidermal permeability barrier recovery.

Protease-activated receptor-2 (PAR-2) is known to be involved in epidermal permeability barrier function homeostasis. PAR-2 activation occurs after barrier disruption and further activation of PAR-2 by activating peptide significantly delays barrier recovery rate. Cockroach and house dust mite allergens, both known to be associated with the development of asthma, allergic rhinitis, and atopic dermatitis, have protease activity, which can activate PAR-2.

Topical application of a novel ceramide derivative, K6PC-9, inhibits dust mite extract-induced atopic dermatitis-like skin lesions in NC/Nga mice.

Atopic dermatitis (AD) is a chronic inflammatory skin disease. K6PC-9 (N-Ethanol-2-hexyl-3-oxo-decanamide) is a novel synthetic ceramide derivative of PC-9S (N-Ethanol-2-mirystyl-3-oxo-stearamide), which was known to be effective in atopic and psoriatic patients. To investigate the immunomodulatory activity of K6PC-9, we examined the effect of K6PC-9 on T lymphocyte and macrophage function and the effect of topical application of K6PC-9 on skin inflammation and AD-like skin lesions in mouse models.

Novel synthetic ceramide derivatives increase intracellular calcium levels and promote epidermal keratinocyte differentiation.

Ceramide is an important constituent of stratum corneum lipids, which act as both physical barriers and signal modulators. We synthesized several ceramide derivatives and investigated their effects on keratinocyte differentiation. RT-PCR and Western blotting showed that the novel synthetic ceramide derivatives K6PC-4 [N-(2,3-dihydroxypropyl)-2-hexyl-3-oxo-decanamide], K6PC-5, [N-(1,3-dihydroxypropyl-2-hexyl-3-oxo-decanamide] and K6PC-9 (N-ethanol-2-hexyl-3-oxo-decanamide) [corrected] These ceramide derivatives elicited a rapid transient increase in intracellular calcium levels, which were measured using laser scanning confocal microscopy.