Inhibition rate (% of control )
Figure 2 – AHE-induced repression of inflammatory cytokines after stimulation of RHE with C . acnes
built up and maintained by our skin ’ s microorganisms remain unimpaired by the application of a product . AHE-containing skin care products exhibited all of these properties in the test procedure ( Figure 1 ). A growth test showed that Staphylococcus and Corynebacterium species , which are central components of our skin microbiome system , both grew faster in the presence of AHE . This can lead to a faster restoration of normal skin microbiome in dysbiosis or in neurodermatitis , where the skin flora is usually disrupted . Cytokeratins 10 ( CK10 ) and 16 ( CK16 ) are essential for skin barrier integrity . 2 To understand the effect of AHE on membrane barrier integrity , we determined the expression pattern of CK10 and CK16 in HaCaT cells with and without AHE-treatment , respectively . Western blot analysis revealed an induction of CK10 in extracts obtained from HaCaT cells after treatment with AHE . Furthermore , this effect was reinforced when the cells were prestimulated with C . acnes . A continuous expression of cytokines following noxious stress causes chronic inflammation and skin damage , which in turn leads to skin disease and ( premature ) ageing . 3 Our in vitro irritation study demonstrated the anti-inflammatory activity of AHE by suppressing the induction of inflammatory markers , such as tumour necrosis factor α , interleukin ( IL ) -1b , IL-6 and IL-8 in peripheral blood mononuclear cells and reconstructed human epidermis ( RHE ) after stimulation with C . acnes ( Figure 2 ). Age-related functional losses and diseases are associated with the accumulation of reactive oxygen species ( ROSs ) and nitrogen species , such as nitrogen monoxide ( NO ). 4 Most isoprostanes are produced by ROSs that catalyse lipid peroxidation . Measuring isoprostanes is an accurate way to assess oxidative stress in vivo and can be correlated with numerous diseases . 5
Cell
Inhibition of ageing symptoms
Prostaglandin E2 ( PGE2 ) -induced inhibition of collagen expression and -promotion of matrix-metalloprotease-1 are two further mechanisms related to ageing . 6 We investigated the effect of 1 % and 2 % AHE on lipopolysaccaride ( LPS ) -induced formation of NO , 8-isoprostane and PGE2 in RAW cells . We found that it elicited a marked decrease in the formation of both when compared to the LPS-treated controls . NO levels fell by 23 % with 1 % AHE and 77 % with 2 % AHE ; for 8-isoprostane , these falls were 8 % and 40 % respectively . Additionally , the expression of PGE2 was reduced by 55 % on treatment with 2 % AHE . The reduction of oxidative stress by ROS scavengers followed by the delay of the age-associated decline in physiological processes and marked prolongation in the mean lifespan can be considered a confirmation of the oxidative stress theory of ageing . Mitochondria are primary sites for ROS accumulation . A regulator of calcineurin-1 ( RCAN1 ) regulates mitochondrial functions and increases susceptibility to oxidative stress . 7 We determined whether AHE produces a reduction in ROS as a marker of oxidative stress by using NHDF cells and H 2
O 2 as a model . We also investigated the effect of AHE on RCAN1 expression .
Figure 3 – Effect of 2 % AHE on ROS formation in NHDF cells upon H 2
O 2 treatment
H 2
O 2
H 2
O 2
+ H 2
O 2
+ AHE H 2
O 2
+ AHE
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