Assessment of effects of an additional dietary natural mineral water uptake on skin hydration in healthy subjects by dynamic barrier function measurements and clinic scoring

BACKGROUND/AIMS

The skin protects the body's organs and tissues from damage and physical, chemical and bacteriological injuries. It also prevents the transcutaneous loss of water. The present study was conducted to assess the effects of additional dietary natural mineral water uptake on skin hydration and cutaneous well-being in subjects with dry skin.

METHODS

Eighty subjects (44 women and 36 males, mean age 56+/-5.6 years) were included in the study, randomised per forearm and stratified by gender. Skin surface hydration, transepidermal water loss (TEWL), sorption-desorption test, skin colour, thickness and micro-relief were evaluated on the forearms. Clinical scoring of dryness, roughness and elasticity was performed by a dermatologist.

RESULTS

An improvement of skin hydration was observed after additional water uptake, statistically modifying the hydration level as well as TEWL, the water-binding capacity of the uppermost layers of the stratum corneum. Improvements of softness, smoothness and skin-moisturising effect were perceived by healthy subjects, and skin micro-relief was improved.

CONCLUSION

We suggest that natural mineral water supplementation may be used in order to improve the hydration of skin dryness as a complementary cosmetic approach.

Topically applied vitamin C enhances the mRNA level of collagens I and III, their processing enzymes and tissue inhibitor of matrix metalloproteinase 1 in the human dermis

Ascorbic acid (vitamin C) is a cofactor required for the function of several hydroxylases and monooxygenases. It is not synthesized in humans and some other animal species and has to be provided by diet or pharmacologic means. Its absence is responsible for scurvy, a condition related in its initial phases to a defective synthesis of collagen by the reduced function of prolylhydroxylase and production of collagen polypeptides lacking hydroxyproline, therefore, they are unable to assemble into stable triple-helical collagen molecules. In fibroblast cultures, vitamin C also stimulates collagen production by increasing the steady-state level of mRNA of collagen types I and III through enhanced transcription and prolonged half-life of the transcripts. The aim of the experimental work has been to evaluate the effect on dermal cells of a preparation of vitamin C topically applied on one side vs placebo on the other side of the dorsal face of the upper forearm of postmenopausal women. Biopsies were collected on both sides and the level of mRNA measured by non competitive reverse transcription-polymerase chain reaction made quantitative by the simultaneous transcription and amplification of synthetic RNA used as internal standards. The mRNA of collagen type I and type III were increased to a similar extent by vitamin C and that of three post-translational enzymes, the carboxy- and amino-procollagen proteinases and lysyloxidase similarly increased. The mRNA of decorin was also stimulated, but elastin, and fibrillin 1 and 2 were not modified by the vitamin. The expression of matrix metalloproteinases 1, 2, and 9 was not significantly changed, but an increased level of tissue inhibitor of matrix metalloproteinase 1 mRNA was observed without modification of tissue inhibitor of matrix metalloproteinase 2 mRNA. The stimulating activity of topical vitamin C was most conspicuous in the women with the lowest dietary intake of the vitamin and unrelated to the level of actinic damage. The results indicate that the functional activity of the dermal cells is not maximal in postmenopausal women and can be increased.

Clinical use of topical retinaldehyde on photoaged skin

BACKGROUND

Retinaldehyde, the natural precursor of retinoic acid, should exert similar effects on photoaged skin.

OBJECTIVE

To establish the efficacy and safety of topical retinaldehyde on photoaged skin.

METHODS

Open and controlled clinical studies using image analysis of silicone skin replicas.

RESULTS

Retinaldehyde proved efficient and safe.

CONCLUSION

Retinaldehyde is efficient and well tolerated for the improvement of the signs of photoaging.

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.

Effect of a conjugated oestrogen (Premarin) cream on ageing facial skin. A comparative study with a placebo cream

The effects of Premarin cream on ageing facial skin were studied in a randomised, double-blind, parallel group study. Fifty-four women aged 52-70 years who had moderate to severe facial cutaneous ageing, applied 1 g of either Premarin cream (0.625 mg conjugated oestrogens per gram of cream), or placebo cream (same composition with the exclusion of conjugated oestrogens) to the face nightly for 24 weeks. Each morning these women protected their face with a sunblock SPF 15. Skin thickness was measured by B-scan ultrasonic echography, and skin microrelief by profilometry. Each subject's facial appearance was also evaluated by the subject herself and by the clinician. A statistically significant difference (P = 0.013) in favour of Premarin cream was detected in skin thickness at week 24. Skin thickness (dermal plus epidermal) for the women who used Premarin cream increased from 1.56 +/- 0.20 mm at baseline to 1.68 +/- 0.19 mm, compared with 1.52 +/- 0.20 mm at baseline to 1.59 +/- 0.19 mm in the placebo group. Premarin cream was also significantly more effective than placebo cream in improving fine wrinkles according to the results at weeks 12 and 24 (P = 0.010 and P = 0.012, respectively). Significant improvement from baseline was detected in both groups for roughness, laxity and mottled pigmentation and/or lentigines; however, there was no significant difference in these parameters between the two treatment groups. No subjects discontinued treatment for a safety reason. In conclusion, Premarin cream produced better results than the placebo cream; the difference was statistically significant for skin thickness and fine wrinkles. Premarin cream was well tolerated locally, and its general safety was good.