Scientific Paper
The research hypothesized that there is no statistical difference between the Langerhans cells, sunburn cells, thymine dimer MMP-1 in both keratinocytes and stroma, and MMP-9 in the underlying stroma terms of the sunscreen-protected sites from 1 MED-exposed site.
The scientist used the sunburn and Langerhans cells due to their strategic location on the skin and their tendency to be affected by the sunburns.
Under methodology, the scientists applied the following experiments. After MED determination, four treatments were conducted on the lower back of each test subject:
- Untreated control: No topical treatment with no UVR exposure.
- Positive control 1: No topical treatment with 1 MED UVR exposure.
- Positive control 2: No topical treatment with 3 MEDs UVR exposure.
- Test treatment: Topical SPF 55 treatment with 55 MEDs UVR exposure.
These observations offer direct and clear evidence that a photostable, broad spectrum high-SPF sunscreen protected against damage at the cellular and molecular levels even under this large UV exposure, confirming the significant protection was present even for these sensitive biomarkers and that the protection was at least as good as the protection of ‘minimal erythema’ reaction.
The fundamental results of the article show that the biomarkers from UVR exposure that had been generally read for intense UV harm incorporate the aggregation of thymine dimers (TT), the acceptance of p53 fix reaction, the expanded articulation of MMPs, the presence of sunburn cells and the vanishing of the Langerhans cells. DNA harm in epidermal cells is essential, and one of the most immediate outcomes of intense UV exposure. DNA can retain UVB, prompting the arrangement of thymine dimers (TT), which have been connected to the expanded danger of creating skin disease. One cell reaction to DNA harm is apoptosis with the development of sunburn cells. Another is the expanded degree of p53 in keratinocytes because p53 is accepted to be effectively associated with the fix of DNA harm. Loss of Langerhans cells in the epidermis can prompt photograph immunosuppression. At long last, the raised articulation of MMPs following UVR exposure assumes a huge function in harming extracellular lattice structures in the dermis, adding to untimely indications of maturing, for example, wrinkles and listing. There are no sunscreens that totally shield skin from sun oriented UV exposure, and they should just be utilized as a feature of the general sun evasion practice.
The findings supported the null hypothesis of the paper to some good extent in general.
The significant thing about the paper is the key finding. Notwithstanding, a high UVA-PF, expansive range high-SPF photostable sunscreen, for example, the one tried here, appeared to offer extra cell and atomic assurance to skin corresponding to the SPF level of the items. Dull suberythemal doses of UVR exposure had been demonstrated to have the option to create critical aggregate biological harm with no indications of ‘negligible erythema.’
The article concludes that a broad spectrum high-SPF photostable sunscreen with high UVA-PF, such as the one tested in the article, can protect against multiple damage biomarkers at the cellular level in skin even under high UVR exposure with efficacy related to the SPF number. The study found no evidence that the high SPF sunscreen masks’ sunburn protection has any ‘invisible’ cellular damage on the skin. The application of high SPF sunscreens can also provide consumers with a margin of safety against erythema when they underapply, as shown in previous work.
I find no bias in the article as the results are evidence-based from experiments. This paper is relevant to this class due to the content covered in terms of biological effects.
Results
Cole, C., Appa, Y., & Ou‐Yang, H. (2014). A broad spectrum high‐SPF photostable sunscreen with a high UVA‐PF can protect against cellular damage at high UV exposure doses. Photodermatology, Photoimmunology & Photomedicine, 30(4), 212-219.