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Carotenoids, a class of phytonutrients, have been well established to boost skin's innate resistance against ultraviolet (UV) B-induced erythema (sunburn). Many of the published clinical studies thus far have focused on the measurement of erythema as the primary clinical indicator of skin protection against UVB radiation. More recent studies have shown that carotenoid supplementation provides even more skin protection than previously shown as new clinical and molecular endpoints beyond UVB-induced erythema have been reported. These recent studies have demonstrated that carotenoids also provide photoprotection against UVA-induced pigmentation and inhibit molecular markers of oxidative stress such as intercellular adhesion molecule 1, heme oxygenase-1, and matrix metalloproteinases 1 and 9. This article provides a comprehensive review of the published clinical evidence on skin benefits of carotenoids in the last five decades and indicates new perspectives on the role of ingestible carotenoids in skin protection.

Phototherapy is the most commonly used modality for repigmenting vitiligo. Currently, UVB emitting devices, including narrow-band UVB (NBUVB) and excimer laser/light, are considered as the treatment of choice. While emitting wavelengths at close proximity, excimer lights emit higher irradiance (HI; W/m2 ) compared to NBUVB. Clinical reports have shown that excimer light is more efficacious in treating vitiligo compared to NBUVB, and we demonstrated that irradiance plays a critical role in promoting melanoblasts differentiation. UVB radiation from the sun is closely associated with photocarcinogenesis of the skin. Sunscreens were used to protect the skin by reducing UVB irradiance (low irradiance (LI) UVB). Sunscreen use was associated with skin cancer reduction in clinical trials. Paradoxically, sunscreen use was associated with increased sunburn episodes in the real-world settings. It was shown that UVB-induced sunburn depends on fluence (J/m2 ) but not irradiance of UVB radiation. We investigated the significance of irradiance in the context of UVB-induced carcinogenesis of the skin. For mice receiving equivalent fluence of UVB exposure, the LIUVB-treated mice showed earlier tumor development, larger tumor burden, and more epidermal keratinocytes harboring mutant p53 as compared to their HIUVB-treated counterparts. These results suggested that at equivalent fluence, LIUVB radiation has more photocarcinogenic potential on the skin compared to its HI counterpart. Since development of sunburn with or without sunscreen use indicates that certain threshold of UVB fluence has been received by the skin at LI and HI, respectively, sunburn episodes with sunscreen use (LIUVB) are more damaging to the skin compared to that without sunscreen (HIUVB) application. In summary, since irradiance plays an important role determining the biological effects of UVB radiation on the skin, future related studies should take this critical parameter into consideration.

Summary Background Ultraviolet B (UVB) radiation increases the serum level of 25-hydroxyvitamin D [25(OH)D]. However, the impact of UVA on vitamin D synthesis by UVB is poorly understood clinically. Objective To examine how different combinations of UVA and UVB radiation affect S-25(OH)D for the same vitamin D–weighted exposure. Materials and Methods Healthy participants were recruited and subsequently divided into four comparable groups regarding initial 25(OH)D value. The different radiations given were whole-body UVB (n = 23), UVAB (n = 23) and UVA (n = 10). The controls (n = 19) had no intervention. The exposure times were chosen to give the same calculated vitamin D effective dose (suberythemal exposures ≤1 standard erythema dose). Blood samples were collected before the first irradiation (t0), immediately after the last (fifth) irradiation (t1) and then after another 2 days after the last (fifth) irradiation (t2). Results UVB and UVAB radiation significantly increased 25(OH)D levels. In the UVA group the increase was less with the same vitamin D–weighted radiation dose. Conclusions Short sessions of UVB or UVAB radiation with the same vitamin D–weighted exposure increased 25(OH)D levels. The UVA dose does not influence 25(OH)D levels under short exposure times. However, there was a significantly lower increase of 25(OH)D levels during longer UVA irradiation (≥9 min).

Background: A combination of oral psoralen with narrowband ultraviolet B (UVB), defined as ‘psoralen-narrowband UVB’, was shown to have a superior efficacy than UVB alone and even a comparable efficacy to psoralen and ultraviolet A in psoriasis. Objective: To find out whether topical psoralen-narrowband UVB provides any additional benefit to narrowband UVB alone in psoriasis. Methods: Nineteen patients with plaque psoriasis were included. Phototherapy was given three times per week. Two symmetrical lesions were selected as target lesions. In the first 12 sessions of phototherapy, the target lesion on one side was treated with 1% 8-methoxypsoralen (MOP) gel 30 min before UVB radiation whereas the target lesion on the other side served as a control. Target lesion scores were assessed at baseline, third, sixth, ninth and 12th sessions. Side effects were recorded. Results: Sixteen patients completed the study. Target lesion scores decreased significantly on both sides (P

Summary Background/purpose: A main mechanism responsible for the efficacy of narrowband ultraviolet (UV)B is thought to be the induction of apoptosis in pathogenetically relevant cells. Narrowband UVB therapy, however, generally induces a relatively long remission period. Recently, evidence that UVB radiation induces regulatory T (Treg) cells was reported. Based on these findings, we examined whether narrowband UVB suppresses contact hypersensitivity (CHS) by inducing Treg cells. Methods: The shaved abdomens of C3H/HeN mice were irradiated with broadband or narrowband UVB. CHS was defined as an ear-swelling response. To examine whether tolerance can be induced by adoptive transfer, lymph node cells from UVB-irradiated mice were injected into naive mice before sensitization and CHS challenge. Results: Narrowband UVB exposure dose dependently suppressed CHS. Significant suppression was observed at doses between 1000 and 3000 mJ/cm2 (P

Background: Ultraviolet (UV) sources have been used to clinically induce herpes simplex lesions in the lips of susceptible individuals. Methods: This study reports the optimization of a UV source for studies involving multiple clinical laboratory sites and subsequent clinical UV induction of cold sore lesions. We describe novel adaptations of a commercially available broadband UV phototherapy lamp that facilitate determination of individual's minimal erythemal dose (MED) and expose the lips with minimal risk of viral transmission to or between the volunteers and technicians. Clinical Results: The source performed well in a clinical setting, with 171 of 386 subjects (44%) developing lesions, an induction rate similar to spectrally similar UV sources. Conclusions: The advantages of consistent and reproducible exposure geometry, additional UV shielding and biological hygiene achieved by our method significantly enhance the execution of UV-induced herpes simplex labialis studies.

Background: Nowadays, sunbeds are very popular worldwide; however – in the majority of countries, including Poland – there are no general guidelines and/or regulations for sunbed usage. Purpose: The aim of the study was to evaluate tanning salons in southwest Poland, paying special attention to safety regulations and basic professional knowledge of the staff members of these units. The hypothesis was put that tanning salons offer better skin and eye protection if their employees are more educated. Methods: Fifty-five sunbed units were visited by the investigators, acting as potential clients. Information was obtained from the staff members in response to previously designed questionnaire. Results: Employees of 41.8% of sunbed units had adequate knowledge of radiation used in their establishments. Goggles were provided in 72.7%, sunglasses in additional 25.5% of salons. Lotions with sunscreens were available in 41.8% of units. Brief medical history of the client was taken in 20% of units. No dermatological examination was performed. Tanning salons, where employed staff were well-orientated in ultraviolet radiation emitted in their units, significantly more frequently recommended usage of goggles and sunscreens (P = 0.0037 and P = 0.0033, respectively). Moreover, in these establishments sunscreens were more commonly available (P = 0.0029). Conclusions: The knowledge of staff members of tanning salons is poor and the eye and skin protection is not enough. The results point out the importance of the knowledge of the staff members in providing skin and eye protection.

We examined the influence of ultraviolet A (UVA) pre-exposure on UVB minimal erythemal dose in 9 Caucasian subjects. Three zones were tested. One zone received only UVB, the second zone received a low UVA dose+UVB, and the third zone received a high UVA dose+UVB. Each zone was divided into 9 circles receiving increasing doses of UVB in order to obtain 3 different UVA-exposed series of 9 circles. Visual and chromometric readings were performed 24 h later. Pre-exposure to UVA caused variations in the slope of the dose-response curve (colorimetric index as a function of the UVB dose). In relation to UVB erythema, these variations indicated a protective effect for 6/9 subjects and an aggressive effect for 3/9 subjects. No predictive criteria were found for inclusion within a group.

Isothipendyl, an H1-receptor antagonist, is an antihistamince used as an antiallergic drug. Its molecular structure is close to the phenothiazines, but it has different photobiological properties. Like phenothiazines, isothipendyl is phototoxic with ultraviolet A (UVA) but it reduces the erythema response to UVB radiation. Isothipendyl seems to have the same protective properties as a sunscreen because its UVB protective properties are effective only if the substance is applied prior to exposure.

Background: Recently, UVB lamps with a peak emission around 311 nm have been used successfully for the treatment of many dermatologic diseases known to be treated with psoralen plus UVA (PUVA). Narrowband UVB (NBUVB) radiation causes less erythema and carcinogenicity with lower cumulative doses than PUVA, while the treatment response remains high. Lichen planus (LP) is a cell-mediated immune response of unknown origin. Methods: We present our results of NBUVB therapy administered to 10 LP patients. The sessions were administered three to four times weekly with an average cumulative dose of 17.7±1.6 J/cm2. Results: Five patients responded completely, and four were partially responsive at the end of the 30th session. Three of the partially responsive cases responded completely at the 31st, 36th and 51st sessions, respectively. Conclusion: Clinical improvements observed in our study as well as the potential advantages of NBUVB imply that it is an inevitable treatment alternative for resistant cases of LP.

Narrowband UVB therapy is versatile and generally preferred to broadband sources. Recently, a convenient device has been described which gives 10 different doses simultaneously to the forearm to determine the minimal erythema dose (MED). It is known there is no relation between sun reactive skin type and MED. Twenty-four individuals were tested using 26% increments giving a range of MED of between 0.38 J/cm2 and over 1.5 J/cm2. When compared to conventional window testing in 15 cases, it was found to be identical or within one increment.

A bilateral comparison study of the therapeutic effects of broad-band ultraviolet (UBV) (FS-40 Sunlamp bulbs) radiation versus UVB radiation plus methoxsalen was conducted in patients with psoriasis. Ten patients were given up to 30 exposures to the two treatments on paired, similarly affected limbs. There was no detectable difference in the response of limbs treated with UVB plus methoxsalen versus UVB phototherapy alone although all patients did show a therapeutic response. Other areas of the body treated with methoxsalen and broad-band UVA radiation (PUVA bulbs) responded more rapidly and to a greater extent than areas exposed to UVB radiation.