Submitted:
04 June 2025
Posted:
06 June 2025
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Abstract
Keywords:
1. Introduction
1.1. Background and Evolution of Regenerative Medicine in Aesthetics
1.2. Significance of Stem Cell-Enriched Treatments in Aesthetic Medicine
1.3. Scope and Objectives of the Review
- Delineating mechanisms underlying aesthetic benefits.
- Evaluating clinical outcomes and safety from recent trials.
- Identifying challenges, including standardization, long-term data, and ethics.
- Analyzing regulatory implications for clinical translation.
- Proposing future research directions for safe, effective integration into practice.
2. Methodology
2.1. Search Strategy and Databases
2.2. Inclusion and Exclusion Criteria
Inclusion Criteria:
- Peer-reviewed articles, systematic reviews, meta-analyses, or human clinical trials.
- Studies on stem cell-enriched treatments (ADSCs, SVF, MSCs, exosomes, PRP) in aesthetic applications (skin rejuvenation, hair restoration, scar revision, fat grafting).
- Human studies in English, reporting clinical outcomes, safety, or mechanisms.
- Published in reputable journals, e.g., Journal of Cosmetic Dermatology, Stem Cells Translational Medicine (Bourin et al., 2013; Gentile et al., 2020).
Exclusion Criteria:
- Non-peer-reviewed articles, abstracts, editorials, or opinion pieces, unless providing regulatory or ethical context.
- Studies on non-aesthetic conditions (e.g., osteoarthritis), unless mechanisms were translatable.
- Animal or in vitro studies without human relevance.
- Non-English articles or pre-2015 publications, except foundational regulatory texts.
- Unreliable sources (e.g., blogs, marketing materials) (Zarei & Abbaszadeh, 2018).
2.3. Data Extraction and Synthesis
2.4. Quality Assessment of Included Studies
3. Findings: Clinical Applications and Outcomes
3.1. Stem Cell-Enriched Treatments for Skin Rejuvenation
3.1.1. Adipose-Derived Stem Cells (ADSCs) and Stromal Vascular Fraction (SVF)
Clinical Outcomes:
- Skin Density and Appearance: ADSC injections improve skin density, hydration, and microcirculation, enhancing appearance (Charles-de-Sá et al., 2015).
- Wrinkle and Pigmentation Reduction: A prospective study showed SVF transplantation improved elasticity, reduced wrinkles, and decreased infraorbital pigmentation at 3–6 months (Lee et al., 2019). Preclinical studies in photo-aged rats confirmed improved texture, thinner epidermis, and increased dermal thickness/collagen (Kim et al., 2018).
- Fat Grafting Enhancement: SVF-enriched fat grafts in breast augmentation achieved 80.2% retention versus 45.1% for non-enriched grafts, reducing secondary procedures (Kølle et al., 2017).
| Treatment Type | Primary Mechanism | Key Clinical Outcomes | Safety Profile | Limitations/Considerations | Reference |
|---|---|---|---|---|---|
| ADSCs/SVF | Paracrine effects (GFs, cytokines, exosomes), angiogenesis, collagen synthesis, immunomodulation | Improved skin density, hydration, capillary vessels; reduced wrinkles, pigmentation; enhanced fat graft retention | Favorable; minor transient events (hematoma, edema, pain); rare serious events | Variability in isolation/preparation; need for long-term data; graft reabsorption | Gentile et al., 2020; Kølle et al., 2017 |
| MSCs/CM | Secretion of GFs, cytokines, exosomes; collagen synthesis, anti-fibrotic, re-epithelialization | Improved pigmentation, wrinkles, texture, firmness, facial lifting | High safety; mild local events (nausea, pain, burning, itch, redness) | Variability in cell source/CM composition; need for standardized protocols | Zhou et al., 2020 |
| Exosomes | Intercellular communication via proteins, microRNAs; anti-aging, anti-inflammatory, pro-angiogenic | Improved skin tone, quality, clarity; reduced wrinkles, pores, pigment; improved sensitive skin symptoms | Good biosafety (cell-free); no allergic reactions; standardization concerns | Lack of standardization; unapproved by FDA; need for more trials | Zhang et al., 2021 |
| PRP | Release of GFs (PDGF, TGF-β, VEGF); fibroblast stimulation, collagen synthesis, ECM remodeling | Improved skin density, thickness, texture, wrinkles; melasma reduction | Favorable; mild transient events (redness, swelling, bruising) | Variability in preparation; inconsistent outcomes | Everts et al., 2020 |
3.1.2. Mesenchymal Stem Cells (MSCs) and Conditioned Media
Clinical Outcomes:
- Facial Rejuvenation: MSC-CM with microneedling improved pigmentation and wrinkles in Asian skin (Lee et al., 2014). ADMSC secretome via microneedling or CO2 laser reduced photoaging scores and wrinkles (Wanitphakdeedecha et al., 2023). Red Deer umbilical cord MSC-CM with radiofrequency enhanced facial lifting and tightening (Ang et al., 2022).
- General Skin Rejuvenation: MSC-CM and fibroblast-derived formulations improved wrinkling, texture, and firmness, with comparable efficacy to cell transplantation (Zhou et al., 2020).
3.1.3. Exosomes
Clinical Outcomes:
- Facial Rejuvenation/Anti-aging: Topical human placental MSC-derived exosomes improved skin tone, clarity, and reduced wrinkles, pores, and pigmentation versus placebo (Kim et al., 2022).
- Sensitive Skin: MSC exosomes improved roughness, scales, erythema, and barrier functions (TEWL, hydration, sebum, pH) (Wang et al., 2022).
- Hyperpigmentation: Rose stem cell-derived exosomes with microneedling reduced pigmentation, redness, and wrinkles (Cho et al., 2024).
3.1.4. Platelet-Rich Plasma (PRP) in Skin Rejuvenation
Clinical Outcomes:
- Skin Density and Thickness: PRP injections increased skin density and thickness across age groups (Alser & Goutos, 2018).
- Texture and Wrinkle Improvement: A RCT showed improved fine/coarse texture and reduced wrinkles versus saline (Kamali et al., 2018).
- Hyperpigmentation (Melasma): PRP with tranexamic acid effectively treated melasma without serious adverse events (Sirithanabadeekul et al., 2022).
- Combined Therapies: PRP with microneedling improved skin homogeneity, though objective dermatological assessments were inconsistent (Everts et al., 2020).
3.2. Stem Cell-Enriched Treatments for Hair Restoration
3.2.1. ADSCs and SVF in Hair Regeneration
Clinical Outcomes:
- Hair Density and Thickness: Autologous stem cell suspensions increased hair density by 29% ± 5% in androgenetic alopecia (Gentile et al., 2017). ADSVCs improved thickness (32% average) and density in 90% of alopecia areata patients (Anderi et al., 2020).
- Wound Healing in Hair Transplant: ADSCs accelerated healing and improved growth post-transplant (Perez-Meza et al., 2017).
3.2.2. Stem Cell-Derived Conditioned Medium and Exosomes for Hair Loss
Clinical Outcomes:
- CM for Hair Loss: ADSC-CM injections increased hair numbers, density, and thickness (up to 32% diameter increase) in androgenetic alopecia and telogen effluvium (Shin et al., 2015).
- Exosomes for Hair Loss: Exosome formulations with plant extracts improved hair regrowth versus placebo, with significant thickness and density gains (Rajendran et al., 2025).
3.2.3. PRP in Hair Restoration
Clinical Outcomes:
- Hair Density and Count: RCTs showed PRP increased hair count (33.6 hairs) and density (45.9 hairs/cm²) in male pattern hair loss (Gentile et al., 2015). A meta-analysis confirmed a 27.55 hairs/cm² increase in AGA (Gupta et al., 2022).
- Hair Thickness: PRP improved thickness consistently (Gentile et al., 2015).
- Histological Changes: Treated scalp showed thicker epidermis, more follicles, and increased vascularity (Gentile et al., 2015).
| Treatment Type | Primary Mechanism | Key Clinical Outcomes | Safety Profile | Limitations/Considerations | Reference |
|---|---|---|---|---|---|
| ADSCs/SVF | Paracrine effects (GFs, cytokines), angiogenesis, follicle stem cell activation | Increased hair density (29%±5%), thickness (32% avg); faster wound healing | Safe; minor pain/bruising; no reported cancer risk | Variability in isolation; need for RCTs | Gentile et al., 2017; Anderi et al., 2020 |
| CM/Exosomes | Secretion of GFs, cytokines, microRNAs; paracrine signaling; prolonged anagen phase | Increased hair numbers, density, thickness; improved regrowth | Safer (cell-free); minor pain; low tumorigenicity | Lack of standardization; unapproved by FDA | Shin et al., 2015; Rajendran et al., 2025 |
| PRP | Release of GFs (PDGF, TGF-β, VEGF); bulge stem cell stimulation; neovascularization | Increased hair count (33.6 hairs), density (45.9 hairs/cm²); improved thickness | No major side effects; minor transient events | High heterogeneity in preparation; short-term follow-up | Gentile et al., 2015; Gupta et al., 2022 |
3.3. Stem Cell-Enriched Treatments for Scar Revision and Wound Healing
3.3.1. ADSCs and SVF in Scar Treatment
Clinical Outcomes:
- Hypertrophic and Keloid Scars: ADSCs reduced collagen deposition, fibroblast proliferation, and scar-related gene/protein expression (collagen I/III, α-SMA, fibronectin), downregulating TGF-β1 and Smad2/3 pathways (Wang et al., 2023). A meta-analysis confirmed fat grafting with ADSCs reduced hypertrophic scars (Gentile et al., 2020).
- Skin Healing: ADSC implantation in surgical wounds improved healing, per physician and patient assessments (Pinto et al., 2020).
- Improved Graft Survival: SVF-enhanced fat grafts improved wound healing in reconstructive surgery (Gentile et al., 2020).
3.3.2. Exosomes in Wound Healing and Scar Reduction
Clinical Outcomes:
- Wound Healing: ADSC-derived exosomes improved healing rates, neovascularization, epithelization, and reduced scarring in animal models (Hu et al., 2024).
- Acne Scars: Exosomes with fractional CO2 laser reduced acne scar scores by 32.5% versus 19.9% in controls, with shorter downtime and milder erythema (Oh et al., 2022).
- General Scarring: Rose stem cell-derived exosomes reduced scarring (Cho et al., 2024).
| Treatment Type | Primary Mechanism | Key Clinical Outcomes | Safety Profile | Limitations/Considerations | Reference |
|---|---|---|---|---|---|
| ADSCs/SVF | Suppress ECM synthesis, promote degradation, influence fibroblast behavior | Reduced collagen deposition, fibroblast proliferation in scars; improved healing; enhanced graft survival | Favorable; minor events; rare dehiscence | Variability in protocols; need for human RCTs | Gentile et al., 2020; Wang et al., 2023 |
| Exosomes | Attenuate inflammation, promote angiogenesis, ECM remodeling; regulate fibroblast differentiation | Accelerated healing; reduced scarring; 32.5% acne scar improvement | Cell-free; minimal effects; good biosafety | Lack of standardization; unapproved by FDA | Oh et al., 2022; Hu et al., 2024 |
3.4. Stem Cell-Enriched Fat Grafting and Tissue Reconstruction
Enhancing Fat Graft Retention with ASCs
Clinical Outcomes:
- Improved Fat Retention: ASC-enriched fat grafts in breast augmentation achieved 80.2% retention versus 45.1% for non-enriched grafts (Kølle et al., 2017).
- Facial Reconstruction: Stem cell-enriched grafts showed superior medium-term volume retention (Gentile et al., 2021).
- Soft Tissue Repair: ASCs enhanced outcomes in breast/facial reconstruction and cosmetic surgery (Gentile et al., 2020).
| Treatment Type | Primary Mechanism | Key Clinical Outcomes | Safety Profile | Limitations/Considerations | Reference |
|---|---|---|---|---|---|
| ASC-Enriched Fat Grafting | Promote angiogenesis, differentiate into endothelial/epithelial cells, secrete GFs/cytokines | Higher retention (80.2% vs 45.1%); superior outcomes in breast augmentation; improved facial reconstruction | Safe; no adverse effects from ASCs; minor liposuction side effects | Variability in isolation; donor factors; optimal delivery under investigation | Kølle et al., 2017; Gentile et al., 2021 |
4. Discussion
5. Conclusion
Acknowledgments
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