Unraveling the molecular and cellular mechanisms of stretch marks

Abstract

Background: Striae distensae, commonly known as stretch marks, are cutaneous lesions that accompany the hormonal upheavals of the major stages of life: puberty and pregnancy. Stretch marks occur in 90% of women, and they appear as red or purple lines that slowly fade to pale lines on the skin. There have been few studies regarding stretch mark origins, and new preventive and corrective treatments are needed. Aims: The aim of this work was to understand the primary genes and proteins involved in the regulation of striae compared to normal skin and to identify the differentially expressed genes and biochemical aspects of SA and SR Importantly, this is the first published study to use a molecular high-throughput approach combined with in vivo evaluation. Methods: In this study, we analyzed the molecular differences between skin with and without stretch marks (rubra [SR] and alba [SA]) of female volunteers using DNA microarray (Whole Human Genome Microarray Kit, 4×44 K, Agilent Technologies) analyses of cutaneous biopsies (2 mm) and in vivo confocal Raman spectroscopy of selected buttock regions, a technique recently introduced as a noninvasive skin evaluation method. Results: We identified gene expression alterations related to ECM, cellular homeostasis, and hormones such as secretoglobulins. Spectral analyses of collagen, fibrillin, and glycosaminoglycans were conducted by Raman spectroscopy at different skin depths. The main differences observed when comparing skin with and without stretch marks were at depths between 75 and 95 μm, corresponding to the dermalepidermal junction and dermis regions and showing differences between normal skin and stretched skin regarding collagen, collagen hydration, and elastin fibers. Conclusion: The results obtained by RNA and protein analyses are complementary and show that significant changes occur in the skin affected by stretch marks. These results suggest new strategies and opportunities to treat this skin disorder and for the development of new and eficiente cosmetic products. K E Y W O R D S molecular biology, Raman, striae distensae | 191 SCHUCK et al. 1 | INTRODUC TI ON Striae distensae (SD), or stretch marks, are linear, atrophic, well-defined cutaneous lesions that occur secondary to changes in connective tissue, which can be associated with obesity, growth spurts, or excess steroids. Many researchers believe that the pathogenesis of SD involves abnormalities of elastic fibers, collagen fibrils, or other ECM components 1 ; however, the specific mechanisms involved are still unclear. Different categories can be used to classify striae, such as striated atrophy, striae distensae, traumatic striae, and striae gravidarum (related to pregnancy), among others. They are normally parallel to each other and perpendicular to the cleft of the skin, suggesting a localized elastic imbalance. 2,3 Striae can be considered a type of dermal scarring, where there is a collagen rupture and separation, and this gap is filled by newly synthesized and realigned collagen. 5,6 In the early stag...

Electrochemical treatment of ex vivo human abdominal skin and potential use in scar management: A pilot study

“…1 Unlike normal skin, scar tissue exhibits characteristic features such as collagen fiber misalignment, excessive dermal fibrosis, and disruption of skin texture. 2,3 Dermal scarring can cause significant physical and psychological distress for patients, and treatment is inexact and complicated. [4][5][6] There remains a need for new methods to treat cutaneous scars beyond the current therapeutic armamentarium.…”

Development of a clinical scale to assess the severity of striae distensae

“…The sample was representative of patients who seek care in dermatologic practice due to SD: Adult women who are overweight with intermediate phototypes and a high prevalence of familial SD. [27][28][29][30] While the population prevalence of SD is still unknown, the homogeneous distribution of SD among the breasts, abdomen, and buttocks Objective and reproducible measures to assess SD severity and compare the efficacy of therapies are valuable in clinical research and should be considered with other outcomes, such as quality of life and the subjective perception of the patient and the researcher. 4,[10][11][12][13][14][15][16][17]19,32,33 As a limitation of this study, the scale was not developed to assess acute (purple or red) SD or other body topographies (eg, lumbar, knee, or inner thigh).…”

“…The sample was representative of patients who seek care in dermatologic practice due to SD: Adult women who are overweight with intermediate phototypes and a high prevalence of familial SD 27‐30 . While the population prevalence of SD is still unknown, the homogeneous distribution of SD among the breasts, abdomen, and buttocks in this sample was crucial in developing a representative scale for these three areas.…”

Association between serum 25‐hydroxyvitamin D levels and the presence and severity of striae gravidarum in primigravid women

“…They concluded that the etiological mechanisms proposed relate to hormones and structural alterations to the integument 12 . Although etiological factors of striae distensae are not the same with SG, they may be considered as similar with etiological factors of SG 24 . We have provided the novel observation that women who have normal values of serum 25(OH)D have a lower risk of having SG than women who have scarce levels of serum 25(OH)D, even after adjustment for confounders.…”