In vivo method for evaluating sunscreen protection against high-energy visible light.

BACKGROUND: Overexposure to sunlight can have many harmful biological effects on the skin, leading to skin cancer and photoaging. As ultraviolet (UV) radiation has been identified as a cause of DNA damage and oxidative stress in the skin, the photoprotection provided by sunscreens is evaluated through their ability to filter UV light, using the sun protection factor (SPF). However, recent data have shown that high-energy visible (HEV) light can also cause biological skin damage. OBJECTIVES: To develop a new in vivo method for evaluating the protection provided by sunscreens across a broad range of wavelengths, including the HEV band, based on multispectral image analysis. METHODS: This study evaluated the absorption properties of six commercially available sunscreens (five SPF 50+ products containing organic UV filters, and one product containing the wide spectrum filter, phenylene bis-diphenyltriazine [TriAsorB™]) and of a control product containing no filter. Multispectral images were acquired from the skin on the forearms of healthy volunteers, before and after application of the test products. Images taken with LEDs emitting light at wavelengths ranging from UV to infrared were used to generate light reflectance maps for each product. The levels of absorbance of light in the UV and visible bands were then calculated. RESULTS: The product containing the wide spectrum filter exhibited significantly higher absorbance over the HEV band (380-450 nm) than the control product and the other commercial sunscreens. All the sunscreens tested showed the same level of absorbance at 365 nm (UVA). CONCLUSIONS: Multispectral imaging provides a simple and reliable in vivo method for assessing the real-world protection provided by sunscreens against all forms of photo-induced skin damage, including that induced by HEV radiation.

Tolerance and efficacy of a new celastrol-containing balm as adjunct care in psoriasis.

BACKGROUND: In patients with psoriasis, the non-lesional skin also presents abnormalities, requiring emollient application on the whole body. OBJECTIVES: To evaluate the tolerance of a new emollient balm containing celastrol, an active ingredient with anti-Th17 immunomodulatory properties used alone or in association with topical or systemic drug treatments or phototherapy, and its efficacy when used alone. METHODS: Adults with body plaque psoriasis applied the product over the whole body once a day for 4 weeks (balm used alone in 41 patients and with ongoing treatment in 50 patients). At D1, D8 ('balm alone' study) or D15 ('balm in association' study) and D29, the dermatologist rated physical and functional signs and assessed pruritus and body global lesion score (evaluating erythema, induration/thickness, scaling and dryness) in the 'balm alone' study. RESULTS: No reaction related to the product was reported, and the tolerance was deemed excellent. In the 'balm alone' study, mean pruritus intensity score significantly decreased at D8 (-39%, P < 0.001) and D29 (-60%, P < 0.001) compared with D1, together with the body global lesion score (-24% at D8 and -26% at D29, P < 0.001). In parallel, quality of life improved, as evidenced by a patient-reported outcome questionnaire. Cosmetic acceptability was good. CONCLUSION: This new emollient balm was very well tolerated by patients with body plaque psoriasis either alone or in association with drug treatment or phototherapy, which is important to ensure long-term compliance. Daily application during one month improved pruritus, physical signs and quality of life.

Effects on mood of acute phenylalanine/tyrosine depletion in healthy women.

Catecholamines have been implicated in the etiology and pathophysiology of mood and anxiety disorders. In the present study, we investigated the effects of experimentally reducing catecholamine neurotransmission by means of acute phenylalanine/tyrosine depletion (APTD). Healthy female volunteers ingested: (1) a nutritionally balanced amino acid (AA) mixture (n = 14); (2) a mixture deficient in the serotonin precursor, tryptophan (n = 15); or (3) one deficient in the catecholamine precursors, phenylalanine and tyrosine (n = 12). Mood was measured at three times: at baseline and both immediately before and after an aversive psychological challenge (public speaking and mental arithmetic) conducted 5 hours after AA mixture ingestion. Acute tryptophan depletion (ATD) lowered mood and energy and increased irritability scores. These effects were statistically significant only after the psychological challenge. The effect of APTD on mood was similar to that of ATD. APTD did not attenuate the anxiety caused by the psychological challenge. These findings suggest that, in healthy women, reduced serotonin and/or catecholamine neurotransmission increases vulnerability to lowered mood, especially following exposure to aversive psychological events.

A comparison of the effects of acute tryptophan depletion and acute phenylalanine/tyrosine depletion in healthy women.

Acute tryptophan depletion (ATD), which is thought to lower serotonin levels, can result in a lowering of mood. In the present study we compared the effect of ATD with acute phenylalanine/tyrosine depletion (APTD) in healthy women. Although considerable evidence relates catecholamines to the regulation of anxiety, there was no difference in anxiety responses in the ATD and APTD groups when the women underwent a mildly stressful psychological challenge. Both ATD and APTD caused a similar lowering of mood. Both depletions also increased heart rate. These results suggest that APTD is a useful method for studying the effect of low catecholamine levels in humans, and that catecholamines are involved in the regulation of mood.

Efficacy and safety of 0.1% retinaldehyde/ 6% glycolic acid (diacneal) for mild to moderate acne vulgaris. A multicentre, double-blind, randomized, vehicle-controlled trial.

BACKGROUND: Retinaldehyde and glycolic acid are both efficient in acne. OBJECTIVE: To evaluate the efficacy and tolerability of a 0.1% retinaldehyde/6% glycolic acid combination (Diacneal) for mild to moderate acne vulgaris. METHODS: Overall physician and patient ratings of acne symptom severity and tolerance were performed at baseline, months 1, 2 and 3. RESULTS: Mean numbers of papules, pustules and comedones were significantly reduced from month 1 onwards. A significant advantage of Diacneal over vehicle was demonstrated on the percentages of patients with ongoing healing lesions at month 2, healing ancient lesions from month 1 and patients with 'important/very important' global improvement from month 2 (50.0 vs. 26.3%) confirmed by patients at month 3 (86.1 vs. 58.8%). Products were well tolerated; only 1 patient had to stop the treatment. CONCLUSIONS: Diacneal, a combination of 0.1% retinaldehyde/6% glycolic acid, is effective and well tolerated in mild to moderate acne vulgaris.

Tolerance profile of retinol, retinaldehyde and retinoic acid under maximized and long-term clinical conditions.

BACKGROUND: Topical retinoic acid (RA) causes irritation of the skin. To prevent this side effect, natural precursors of RA have been proposed. The aim of the present study was to compare the local tolerance profiles of retinol (ROL), retinaldehyde (RAL) and RA. METHODS: ROL, RAL and RA were studied using repeated insult patch tests for 14 days (n = 6). Similarly, RAL and RA were assessed in long-term clinical use for 44 weeks (n = 355). Clinical scoring on irritation, measurement of transepidermal water loss (barrier function) and laser Doppler blood flow perfusion units (irritation) were performed. RESULTS: Under maximized conditions, an equally low irritation potential for ROL and RAL and a more pronounced irritant effect with RA could be demonstrated clinically (p < 0.05 in the intergroup analysis). Furthermore, RAL and RA induced more scaling than ROL (p < 0.05), and ROL and RA tended to induce more burning/pruritus than RAL (nonsignificant). The TEWL values were low with ROL and high with RAL and RA (nonsignificant, intergroup analysis). The laser Doppler measurements confirmed pro-irritating effects of RA and the nonirritating effects of ROL and RAL (p = 0. 001, intergroup analysis). The long-term clinical study showed that the study population developed a high frequency of erythema (44% of the population), scaling (35%) and burning/pruritus (29%) with RA in the first 4 weeks of treatment, whereas these 3 parameters were significantly less frequent with RAL (p < 0.0001 in the intergroup analysis). CONCLUSION: The natural retinoids ROL and RAL do have a good tolerance profile, in contrast with the irritating potential of RA.

Retinaldehyde alleviates rosacea.

BACKGROUND: Anecdotal observations suggest that retinoic acid may be effective in mild rosacea. AIM: Our aim was to investigate, by an exploratory clinical and instrumental study, the effects of a topical formulation with the retinoic acid precursor retinaldehyde, in patients with vascular signs of facial rosacea. METHODS: Female patients were treated with a 0.05% retinaldehyde cream that was applied once daily for 6 months. Clinical assessments of persistent erythema and telangiectasia were performed every month, using a 4-point severity score (absent to severe). The clinical response for each parameter was defined as a decrease of at least 1 grade in the severity score. In addition, erythema was further evaluated by measurement of the a* parameter, using a spectrophotometer on lesional and nonlesional areas. RESULTS: A total of 23 women comprised the study population. At baseline, 10 patients had diffuse erythema, 3 patients had isolated telangiectasia and 10 patients had both. During retinaldehyde treatment, a clinical response was revealed in about 75% of the patients with erythema, after 5 months (p < 0.05). Similarly, isolated telangiectasia responded to retinaldehyde, although to a lesser extent and after a longer period of treatment (46% responders after 6 months, nonsignificant). Using the spectrophotometer, the a* parameter diminished in patients with erythema by about 15%, after 2 months of treatment (p = 0.001). CONCLUSION: This study indicates that retinaldehyde has beneficial effects on the vascular component of rosacea.

Sensory analysis of four medical spa spring waters containing various mineral concentrations.

BACKGROUND: Medical spa spring waters (MSSWs) have been extensively used as adjunctive treatments for various skin conditions to provide skin comfort. We carried out a double-blind study to compare the sensory profile of four MSSWs with increasing mineral content. METHODS: A panel of 36 women, trained to perform comparative sensory analysis, applied in pairs four MSSWs with mineral contents of 0.2, 0.45, 5, and 11 g/L on the right and left cheeks. At baseline, 5 min, and 10 min after the applications, the subjects evaluated each water for the following factors using a computerized analog scale: freshness, mild stinging, softness, suppleness, and comfort of the skin. RESULTS: After 5 min, all four waters induced a sensation of freshness, irrespective of their mineral concentration. A mild stinging was also perceived with all four waters, with a magnitude that was dependent on the mineral density. After 10 min, softness, suppleness, and skin comfort were the prominent features induced by the waters, but the lower the mineral content, the greater these perceptions. Statistically significant differences were demonstrated between the 0.2 g/L group and the 5 and 11 g/L groups for stinging (P = 0.0001), softness and suppleness (P < 0.05), and skin comfort (P = 0.006) after 10 min. CONCLUSIONS: Our results indicate that the sensory effects provided by MSSWs when topically applied depend on their mineral concentration.

Profilometric evaluation of photodamage after topical retinaldehyde and retinoic acid treatment.

OBJECTIVE: We compared the activity and tolerance profile of a 0.05% retinaldehyde cream with a 0.05% retinoic acid cream and the retinaldehyde vehicle in patients with photodamaged skin of the face. METHODS: A silicone replica of the left crow's feet area was taken at baseline and at weeks 18 and 44. Skin replicas were then analyzed by means of an optical profilometry technique. Standard wrinkle and roughness features were then calculated and statistically analyzed. The tolerance profile of the test products was also clinically evaluated during the entire study. RESULTS: A total of 125 patients (40 in the retinoic acid group, 40 in the retinaldehyde group, and 45 in the vehicle group) were studied. At week 18, a significant reduction of the wrinkle and roughness features was observed with both retinaldehyde and retinoic acid. At week 44, a less pronounced reduction was demonstrated in both active groups. No statistically significant changes were observed with the retinaldehyde vehicle at any assessment point. A total of 135 patients constituted the safety population. Retinaldehyde was well tolerated during the entire study. In contrast, retinoic acid caused more local irritation, and affected compliance of the patients. CONCLUSION: Retinaldehyde was efficacious and well tolerated in patients with photodamage.