A new combination of Acetyl Tripeptide-30 Citrulline, Pseudoalteromonas ferment extract and Pentapeptide-18 could be the best way to get rid of stretchmarks. Míriam Mateu, Monserrat Mangues, Juan Cebriá & Cristina Carreño introduce the material
Striae distensae, or stretchmarks, are a common disfiguring condition associated with continuous and progressive stretching of the skin which occurs in a number of physiological and pathological states such as pregnancy or adolescent growth spurts, being more visible in the breasts, abdomen, back, buttocks and thighs.[1,2] The unaesthetic effect of stretchmarks has a strong negative psychological impact in many people, particularly women.
Recent striae are covered with a thin and generally atrophic epidermis which appears as raised pink/purple linear lesions without significant depression of the skin with an often smooth and tense surface (figure 1).[3] Over time striae become paler, depressed and tend to become crumpled and atrophic giving the sensation of vacuity at palpation. They are hairless and no sweat or sebum excretion appears to be present.[4]
Striae ruptures can occur unexpectedly in the direction of minimal tensions where the tissue is the weakest and least able to sustain mechanical stress. The main causes of stress rupture of the connective tissue framework due to alteration of extracellular matrix (ECM) components are the enhanced proteolysis in striae, which is linked to difficult wound healing, and the decrease in fibroblast proteosynthesis levels, which appear to be quiescent, slightly spread out and become globular.
Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases collectively capable of essentially degrading all ECM components.[5] MMPs represent the major class of enzymes responsible for ECM metabolism and play an important role in excessive breakdown of connective tissue components, such as striae distensae.
Strong alterations in structures providing tensile strength and elasticity to the skin appear to be related with the appearance of striae distensae. Skin affected by striae presents an increase in the ground substance content and a reorganisation and significant reduction of the elastic fibre network, especially collagen, elastin and fibrillin fibres. The collagen bundles are thin, short, uncoiled, stretched out, fragmented and widely separated from each other by the abundant ground substance and often parallel to the epidermis. In striated skin, the dermal matrix appears looser and more floccular than in normal skin.
Elastic fibres are insoluble central cores of elastin surrounded by connective tissue microfibrils whose principal structure component is the fibrillin glycoprotein. Elastin forms an extensive cross-linked network of fibres playing a main role in elasticity functions, while in striated skin, elastic fibres are thin and fragmented forming heaps and looking retracted and even dystrophic at the junction between healthy and striated skin.[6]
Variations in microvasculature size and melanocyte activity appear to be the causes of striae distensae colours. In recent striae, edema seems to be present between melanocytes and keratinocytes, while in older striae there is a decrease in melanogenesis and the number of melanocytes.
The treatment of existing stretchmarks must be oriented to recover the dermal structure and a preventive treatment should maintain and improve it, getting the dermis into good condition and increasing the skin’s ability to stretch.
ACTIVE PREVENTION
Vanistryl is a new cosmetic ingredient that combines Acetyl Tripeptide-30 Citrulline, Pseudoalteromonas ferment extract and Pentapeptide-18 which act through different mechanisms to treat stretchmarks that are already formed and to prevent the formation of new ones. This new combination of actives incorporates a new delivery system formed by mixed micellar systems.
Acetyl Tripeptide-30 Citrulline is a synthetic tetrapeptide obtained by combinatorial chemistry that specifically inhibits human MMPs, preventing the degradation of the ECM components disrupted in the formation of stretchmarks and preventing the formation of new ones by strengthening the skin to withstand distension.
The glycoprotein Pseudoalteromonas ferment extract is obtained by biosynthesis from the bacterial strain Pseudoalteromonas antarctica NF3. Its collagen and elastin boosting properties reconstruct the dermal components and give the integrity and elasticity that skin needs to recover.
Pentapeptide-18 is a pentapeptide that modulates acetylcholine release from neuron cell cultures, relaxing muscle tissue surrounding striae to permit the healing of striae and prevent the formation of new stretchmarks.
The three active ingredients are incorporated in a mixed micelles delivery system. The mixed micelles are small size aggregates with a spherical-like shape composed of a non-ionic surfactant and phospholipids. The mixed micellar systems penetrate between the lipid bilayers of the stratum corneum due to their small size and are then reconstituted by water dilution into liposomes of a bigger size, enhancing the penetration of actives through the stratum corneum (SC) (figure 2).
MATERIALS & METHODS
IN VITRO TEST
The inhibitory effect of Acetyl Tripeptide-30 Citrulline 0.5mM on the activity of human MMP-1, MMP-2, MMP-3 and MMP-9 was evaluated in vitro with an Automated multiplate fluorescence reader (Fluostar Galaxy, BMG Labtech Gmbh, Oftenburg, Germany) monitoring the fluorescence released by quenched gelatine (DQ Gelatin from pig skin) digested by the MMPs.
IN VIVO TEST
Twelve female volunteers with clinically assessed recent stretchmarks on the abdomen or the thighs were enrolled for the in vivo study. The volunteers applied twice a day a cream containing 5% of Vanistryl on one stretchmark area and a placebo cream on another area of stretchmarks for 60 days. The appearance of stretchmarks was evaluated qualitatively and quantitatively before the treatment and after 30 and 60 days of application.
Qualitatively, an experienced clinical grader scored visually, from one (worst) to five (best), the appearance of the relief, firmness, softness, brightness, perception by touch, colour, length and thickness and general appearance.
Quantitative evaluations were also performed. Skin surface images were captured by Visioscan VC 98 and analysed with the software SELS2000 focusing on the skin surface improvement, dryness and firmness. Furthermore, to analyse colour changes, melanin and erythema index
were measured with the Mexameter MX18, while to study skin elasticity changes, the Soft Mini Three instrument was used.
Photographs of the treated areas were taken before and after the study.
RESULTS
IN VITRO TEST
Inhibition of human MMPs: Acetyl Tripeptide-30 Citrulline proved to inhibit the production of human MMP-2 completely, MMP-9 was inhibited by 63.1%, and the inhibition of MMP-1 and MMP-3 was 34.7% and 39.1% respectively (figure 3).
IN VIVO TEST
Clinical evaluation by a dermatologist: The results obtained from the clinical evaluation showed a significant improvement for all the volunteers with the cream containing the combination of active ingredients (figure 4). Almost all parameters improved in 100% of the volunteers after 60 days of treatment proved highly significant compared to a placebo (p<0.02).
The dermatologist evaluation showed a significant improvement in the appearance (38.89%), firmness (70.83%), softness (133.33%), brightness (75%), perception by touch (28.61%), colour (50.58%), length and thickness (29.86%) and general appearance (137.5%) of the stretchmarks.
INSTRUMENTAL ASSESSMENTS
The results of the measurements of the skin surface with the Visioscan VC98 were positive after 30 and 60 days (figure 5). Skin dryness and skin firmness improved significantly in all volunteers after 60 days of treatment with the cream containing Vanistryl in comparison with the basal time (p<0.01). The placebo cream showed no significant variations in these parameters.
The melanin and erythema index decreased significantly after 60 days (p<0.012) (figure 6). The colour of stretchmarks improved in 75% of volunteers, and this value was significant compared to placebo. The erythema was reduced by 18.05% after 60 days of treatment.
Skin elasticity presented a highly significant increase after 30 days (p<0.0034) and 60 days (p<0.0024) of treatment with a cream containing Vanistryl compared to a placebo. Skin elasticity increased by 44% and all the volunteers experienced an improvement at the end of the study (figure 7). The efficacy of this new material was ultimately proved in a visible reduction of stretchmarks (figure 8):
The new material achieved good results in both in vitro and in vivo anti-stretchmarks efficacy tests. Acetyl Tripeptide-30 Citrulline showed an inhibition of human MMP-1, MMP-2, MMP-3 and MMP-9 in vitro. Furthermore it presented an improvement of the general appearance, firmness, softness, brightness, perception by touch, colour, length and thickness, dryness and elasticity in vivo. The results confirmed that collagen and elastin boosting properties of Pseudoalteromonas ferment extract helped to regenerate the dermal components and gave the integrity and elasticity lost. Pentapeptide-18 relaxed muscle tissue surrounding striae which permitted its healing and Acetyl Tripeptide-30 Citrulline prevented the degradation of the ECM components by inhibiting human MMPs and the formation of new stretchmarks by strengthening the skin to withstand distension. It also complemented the action of Pseudoalteromonas ferment extract by avoiding the degradation of the new synthesised collagen.
Vanistryl is an ingredient combining Acetyl Tripeptide-30 Citrulline, Pseudoalteromonas Ferment Extract and Pentapeptide-18 which reconstruct the dermal components, restore the integrity and elasticity that skin needs to recover helping to heal the striae, and also prevent the appearance of new stretchmarks by strengthening the skin and preventing degradation of the ECM components.