Controlling Reactive Oxygen Species in Skin at Their Source to Reduce Skin Aging

Protective effect of human amniotic membrane extract against hydrogen peroxide-induced oxidative damage in human dermal fibroblasts

OBJECTIVE

One of the main approaches to preventing skin ageing is to protect fibroblast cells from oxidative stress. The promoting effect of the human amniotic membrane extract (hAME) on re-epithelization, proliferation and migration of cells in wound healing has been already well studied. This experimental study aimed to investigate the antioxidant activity of hAME against hydrogen peroxide (H₂ O₂ )-induced dermal fibroblast damage.

METHODS

Here, to establish the ageing model, human foreskin fibroblasts (HFFs) were exposed to 200 μM H₂ O₂ for 2 h. HFFs were treated with 0.1 mg/ml AME for 24 or 48 h before or/and after H₂ O₂ exposure. A total of 48 h following the H₂ O₂ treatment, we measured cell proliferation, viability, senescence-associated β-galactosidase (SA-β-Gal), antioxidants and preinflammatory cytokine (IL-6) levels, as well as the expression of senescence-associated genes (P53 and P21).

RESULTS

The obtained results indicated that under oxidative stress, AME significantly increased cellular viability and not only promoted the cell proliferation rate but also attenuated apoptotic induction condition (p < 0.001). AME also significantly reversed the SA-β-Gal levels induced by H₂ O₂ (p < 0.001). Additionally, both pre- and post-treatment regimen by AME down-regulated the expression of senescence marker genes (p < 0.001). Moreover, AME declined different oxidative stress biomarkers such as superoxide dismutase and catalase and increased the glutathione amount.

CONCLUSION

Altogether, our results indicated that AME had a remarkable antioxidant and antiageing activity as pre- and post-treatment regimen, pointing to this compound as a potential natural-based cosmeceutical agent to prevent and treat skin ageing conditions.

Trans-plasma membrane electron transport in mammals: functional significance in health and disease

Trans-plasma membrane electron transport (t-PMET) has been established since the 1960s, but it has only been subject to more intensive research in the last decade. The discovery and characterization at the molecular level of its novel components has increased our understanding of how t-PMET regulates distinct cellular functions. This review will give an update on t-PMET, with particular emphasis on how its malfunction relates to some diseases, such as cancer, abnormal cell death, cardiovascular diseases, aging, obesity, neurodegenerative diseases, pulmonary fibrosis, asthma, and genetically linked pathologies. Understanding these relationships may provide novel therapeutic approaches for pathologies associated with unbalanced redox state.

The influence of aging and diabetes on heat transfer characteristics of the skin to a rapidly applied heat source

BACKGROUND

Numerous studies have examined the blood flow of the skin at rest and in response to sustained heat and shown that, in older people and people with diabetes, the skin blood flow response to heat is diminished compared to younger people. It is not sustained heat, however, that usually causes burns; it is a more rapid application of heat.

SUBJECTS AND METHODS

Ten younger subjects, 10 older subjects, and 10 subjects with diabetes were examined before and after applying a water-filled thermode to the skin above the quadriceps muscle to observe the changes in skin temperature and skin blood flow and the ability of the skin to absorb heat after a 2-min heat exposure with water at 44°C.

RESULTS

Skin temperature rose from 31.2°C at rest to 38.3°C after 2 min of heat application in all subjects (P > 0.05 between groups). The calories required in the younger group of subjects was 2.26 times the calories required in the older group of subjects for the same change in skin temperature and 13.8 times the calories needed to increase skin temperature in the subjects with diabetes. Furthermore, the blood flow at rest was lower in people with diabetes than older subjects and both groups less than that seen in younger subjects. The blood flow response to heat was slower in the subjects with diabetes compared to the older subjects and much slower than that seen in the younger subjects.

CONCLUSIONS

Reduced skin blood flow of older and subjects with diabetes, decreased thickness of the dermal layer, and increased subcutaneous fat, as well as damage to transient receptor potential vanilloid 1 receptors, may account for some of the differences between the groups.