Dietary, but not Topical, Alpha-linolenic Acid Suppresses UVB-induced Skin Injury in Hairless Mice when Compared with Linoleic Acid¶

Abstract

Peroxidizability of fatty acids in the air is roughly proportional to the number of double bonds, but in vivo peroxidation proceeds in a more complex manner. Here, we compared the effects of dietary and topically applied oils enriched with linoleic acid (LA, 18:2n‐6) or alpha‐linolenic acid (ALA, 18:3n‐3) on UV‐induced skin injury in a strain of hairless mice. The UVB‐induced erythema score was significantly lower in mice with topically applied creams containing LA and ALA than in mice with the basal cream; no significant increase in the score was detected in the ALA group compared with the LA group. However, dietary ALA inhibited the increase in erythema score after UVB irradiation compared with LA. The peroxidizability index of the skin total lipids was significantly higher, but UVB‐induced prostaglandin E2 (PGE2) production was significantly lower in the group fed an ALA‐rich diet compared with the group fed an LA‐rich diet. The levels of thiobarbituric acid–reactive substances, estimated in the presence of butylated hydroxytoluene in the assay mixture, were not affected by UVB treatment or by the dietary fatty acids, but the severity of the skin lesion was associated with PGE2 levels. These results indicate that the type of fatty acids, n‐6 or n‐3, is critical for the suppression of UVB‐induced skin lesion when the skin fatty acids are modified by dietary manipulation. Anti‐inflammatory activity of dietary flaxseed oil with relatively high ALA and low LA contents was demonstrated in UVB‐irradiated hairless mice.

Omega-3 fatty acid intake and decreased risk of skin cancer in organ transplant recipients

“…Another study showed that EPA and DHA supplements lowered the risk of SCCs (and BCCs) in lung transplant recipients through higher intakes of long-chain omega-3 PUFA were involved than seen in the present study participants [17], or than seen in other studies that showed null results for BCC [41]. The protective effect of α-linolenic acid intake on BCC is unlikely to be due to conversion to EPA or DHA which occurs only to a very limited extent [42][43][44], but rather may result from independent actions such as lowering inflammation markers [45,46] and protecting against photodamage [47]. However, the evidence is sparse and inconclusive, and previous studies have shown little to no effect of dietary intake on BCC [41].…”

The Novel Rho Kinase (ROCK) Inhibitor K-115: A New Candidate Drug for Neuroprotective Treatment in Glaucoma

“…The TBARS assay was carried out according to previously reported methods 73,74 with minor modifications. TBARS assays measure the total level of oxidized lipids based on the reaction of malondialdehyde (MDA), one of the end products of lipid peroxidation, with thiobarbituric acid (TBA).…”