Regenerative application of stromal vascular fraction cells enhanced fat graft maintenance: clinical assessment in face rejuvenation

Effects of Nanofat in Plastic and Reconstructive Surgery: A Systematic Review

BACKGROUND

Since nanofat was first introduced by Tonnard in 2013, numerous studies have reported positive findings with its use; however, concerns exist regarding its effects and mechanisms, and the various methods used to generate nanofat also remain unclear. The authors conducted a systematic review to evaluate the efficacy of nanofat grafting alone in plastic and reconstructive surgery.

METHODS

The MEDLINE, Embase, Cochrane Central, Web of Science, and Scopus databases were searched for studies related to the use of nanofat grafting alone in plastic and reconstructive surgery. Outcomes of interest were all clinical results in humans or animals.

RESULTS

Twelve studies were included. No meta-analysis was conducted due to the clinical heterogeneity of the studies. In general, included studies had a low level of evidence. Six studies ( n = 253 patients) showed significant improvements in scar characteristics based on Patient and Observer Scar Assessment Scale, FACE-Q scale, physician assessment, patient satisfaction, and Vancouver Scar Scale scores. Four studies described the benefits of nanofat in skin rejuvenation (wrinkles, fine rhytides, pigmentation, and discoloration) through photographs, questionnaires, and indentation indices. Histologic evaluation illustrated overall increases in skin thickness, collagen, and elastic fibers. Three experimental studies showed the beneficial effects of nanofat on fat grafting, diabetic wound healing, and hair growth, with compelling histological evidence. No severe complication was reported.

CONCLUSIONS

Nanofat grafting shows potential benefits in scar and antiaging treatments, with conclusive histological evidence. Clinical studies of fat grafting, wound healing, and hair growth should be conducted, based on the results of this systematic review. Nanofat grafting could be a practical and safe procedure.

Effectiveness and Safety of Different Methods of Assisted Fat Grafting: A Network Meta-Analysis

OBJECTIVE

Numerous studies have proposed the utilization of stromal vascular fraction (SVF), adipose-derived stem cells (ADSCs), and platelet products as auxiliary grafting techniques to improve the survival rate of fat grafts. This study aimed to evaluate the efficacy and safety of various fat grafting methods since 2010 through a network meta-analysis, aiming to identify the most effective technique for fat grafting.

METHODS

Clinic trials on assisted fat grafting were searched from Pubmed, Embase, Web of Science, and the Cochrane Library, spanning the period from January 1, 2010 to March 2024. The risk of bias in the included trials was meticulously assessed using the Cochrane risk of bias tool. The survival rate of fat grafts served as the primary evaluation metric for effectiveness, while complications were employed as the indicator for safety.

RESULTS

The study incorporated 31 clinic trials, involving a total of 1656 patients. The findings indicated that the survival rate with assisted fat grafting significantly surpassed that of simple fat grafting (SUCRA, 10.43%). Notably, ADSC-assisted fat grafting exhibited the highest survival rate (SUCRA, 82.17%), followed by Salvia miltiorrhiza (SM)-assisted fat grafting (SUCRA, 69.76%). In terms of safety, the most prevalent complications associated with fat grafting were fat sclerosis and fat necrosis. Adc-assisted fat grafting was correlated with the lowest incidence of complications (SUCRA, 41.00%), followed by simple fat grafting (SUCRA, 40.99%). However, PRP-assisted (SUCRA, 52.86%) and SVF-assisted fat grafting (SUCRA, 65.14%) showed higher complication rates.

CONCLUSION

Various methods of assisted fat grafting can significantly enhance the survival rate, but they often fail to effectively mitigate the incidence of complications. Compared to other methods, adipose mesenchymal stem cells-assisted fat grafting consistently yielded a higher survival rate of grafts and fewer complications. Consequently, this approach represents a relatively effective method for assisting in fat grafting at present.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Mechanical Purification of Lipofilling: The Relationship Between Cell Yield, Cell Growth, and Fat Volume Maintenance

BACKGROUND

The mechanical manipulations of fat tissue represented from centrifugation, filtration, washing, and fragmentation were considered the most effective strategies aiming to obtain purified lipofilling with different impacts both in terms of adipose-derived stem cells amount contained in stromal vascular fraction, and fat volume maintenance.

OBJECTIVES

The present work aimed to report results in fat volume maintenance obtained by lipofilling purification based on the combined use of washing and filtration, in a clinical study, and to deeply investigate the adipose-derived stem cells yield and growth capacity of the different stromal vascular fraction extraction techniques with an in vitro approach.

METHODS

A preliminary prospective, case-control study was conducted. 20 patients affected by face and breast soft tissue defects were treated with lipofilling and divided into two groups: n = 10 patients (study group) were treated with lipofilling obtained by washing and filtration procedures, while n = 10 (control group) were treated with lipofilling obtained by centrifugation according to the Coleman technique. 6 months after the lipofilling, the volume maintenance percentage was analyzed by clinical picture and magnetic resonance imaging comparisons. Additionally, extracted stromal vascular fraction cells were also in vitro analyzed in terms of adipose-derived stem cell yield and growth capacity.

RESULTS

A 69% ± 5.0% maintenance of fat volume after 6 months was observed in the study group, compared with 44% ± 5.5% in the control group. Moreover, the cellular yield of the control group resulted in 267,000 ± 94,107 adipose-derived stem cells/mL, while the study group resulted in 528,895 ± 115,853 adipose-derived stem cells /mL, with a p-value = 0.1805. Interestingly, the study group showed a fold increase in cell growth of 6758 ± 0.7122, while the control group resulted in 3888 ± 0.3078, with a p < 0.05 (p = 0.0122).

CONCLUSIONS

The comparison of both groups indicated that washing and filtration were a better efficient system in lipofilling preparation, compared to centrifugation, both in terms of volume maintenance and adipose-derived stem cell growth ability.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .

Comparative Efficacy and Safety of Cell-Assisted and Conventional Lipotransfer in Facial Filling: A Systematic Review and Meta-Analysis

PURPOSE

We aim to compare the efficacy and safety of cell-assisted lipotransfer (CAL) and conventional lipotransfer (CLT) in facial filling.

METHODS

The PubMed and Embase databases were searched for relevant publications until February 2023. All studies evaluating the efficacy and safety of cell-assisted and conventional lipotransfer in facial filling were included. We calculated pooled standardized mean difference (SMD) and 95% CIs for continuous outcomes and pooled risk ratio (RR) with 95% CIs for binary outcomes. The Cochrane's Risk of Bias Tool and the Newcastle-Ottawa Scale (NOS) were used to evaluate the quality of studies.

RESULTS

A total of 15 studies with 737 patients were included in this analysis. The fat survival rate and patient satisfaction rate were significantly higher in the CAL group compared to the CLT group (SMD: 3.04, 95% CI 2.09-3.99; RR: 1.34, 95% CI 1.08-1.67). However, no significant difference in complication rates (RR: 0.95, 95% CI 0.50-1.81) and a lower secondary operation rate in the CAL group (RR: 0.52, 95% CI 0.03-0.82) were observed. No obvious publication bias was observed in the funnel plot (Egger's P values = 0.084 and 0.403).

CONCLUSIONS

Based on the pooled results, we tentatively conclude that CAL may have superior fat survival rate and satisfaction rate compared to CLT in facial filling, without compromising patient safety. However, the majority of the included studies were observational studies with small sample sizes. Future research should focus on investigating the long-term efficacy and safety of these techniques.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Exosomes derived from BMSCs enhance diabetic wound healing through circ-Snhg11 delivery

BACKGROUND

Exosomes (Exos) generated from bone mesenchymal stem cells (BMSCs) are elucidated to enhance cutaneous wound healing in mice models of diabetes mellitus (DM). While underlying mechanisms remain unknown.

METHODS

Next-generation sequencing (NGS) was used to examine changes in circRNA expression levels following Exo treatment. Luciferase assays were used to determine the interactions between RNAs. Immunofluorescence staining was used to examine reactive oxygen species (ROS) in endothelial progenitor cells (EPCs) cultured in high glucose (HG) conditions. Therapeutic effects regarding Exos were also examined by immunofluorescence.

RESULTS

We found that Exo treatment enhanced cutaneous wound healing significantly. NGS indicated that circ-Snhg11 was involved in Exo-mediated tissue repairing. Downregulation of circ-Snhg11 decreased Exo-mediated therapy responses during wound healing in diabetic mouse. Our luciferase reporter data confirmed that SLC7A11 and miR-144-3p were circ-Snhg11 downstream targets. miR-144-3p overexpression or SLC7A11 knockdown altered the protective effects of circ-Snhg11 upon EPCs exposed to HG conditions. Upregulation of circ-Snhg11 incremented therapy effects of Exo treatment during wound healing in DM mice through enhanced angiogenesis along with a reduction in GPX4-mediated ferroptosis.

CONCLUSIONS

circ-Snhg11 in BMSC-Exos enhanced SLC7A11/GPX4-mediated anti-ferroptosis signals via miR-144-3p sponging resulting in enhanced diabetic wound healing and improved angiopoiesis.

Mesenchymal stromal cell-derived magnetic nanovesicles for enhanced skin retention and hair follicle growth

BACKGROUND AIMS

Extracellular vesicles and exosome-mimetic nanovesicles (NVs) derived from mesenchymal stromal cells (MSCs) have emerged as promising to promote hair growth. However, short local skin retention after subcutaneous administration hinders their clinical applications.

METHODS

In this study, we prepared magnetic nanovesicles (MNVs) from iron oxide nanoparticle-incorporated MSCs. MNVs contained more therapeutic growth factors than NVs derived from naive MSCs, and their localization and internalization were manipulated by external magnetic field.

RESULTS

Following the subcutaneous injection of MNVs into a mouse model of depilation-induced hair regeneration, the magnetic attraction increased their skin retention. Then, the cellular proliferation and β-catenin signaling in hair follicles (HF) were markedly enhanced by MNV injection and magnetic field application. Furthermore, an acceleration of HF growth was revealed by histological analysis.

CONCLUSIONS

The proposed strategy can enhance the therapeutic potential of MSC-derived NVs for hair regeneration and other dermatological diseases.

Mechanical and Enzymatic Digestion of Autologous Fat Grafting (A-FG): Fat Volume Maintenance and AD-SVFs Amount in Comparison

BACKGROUND

Currently, several techniques for autologous fat graft (A-FG) preparation aimed at obtaining purified tissue exist. Both mechanical digestions via centrifugation, filtration, and enzymatic digestion were considered the most effective with different impacts in terms of adult adipose-derived stromal vascular fraction cells (AD-SVFs) amount that volume maintenance.

OBJECTIVES

This article aimed to report the in vivo and in vitro results, represented by fat volume maintenance and AD-SVFs amount, obtained by four different procedures of AD-SVFs isolation and A-FG purification based on centrifugation, filtration, centrifugation with filtration, and enzymatic digestion.

METHODS

A prospective, case-control study was conducted. In total, 80 patients affected by face and breast soft tissue defects were treated with A-FG and divided into four groups: n=20 were treated with A-FG enhanced with AD-SVFs obtained by enzymatic digestion (study group 1 [SG-1]); n=20 were treated with A-FG enhanced with AD-SVFs obtained by centrifugation with filtration (SG-2); n=20 were treated with A-FG enhanced with AD-SVFs obtained by only filtration (SG-3); n=20 were treated with A-FG obtained by only centrifugation according to the Coleman technique (control group [CG]). Twelve months after the last A-FG session, the volume maintenance percentage was analyzed by magnetic resonance imaging (MRI). Isolated AD-SVF populations were counted using a hemocytometer, and cell yield was reported as cell number/mL of fat.

RESULTS

Starting with the same amount of fat analyzed (20 mL), 50,000 ± 6956 AD-SVFs/mL were obtained in SG-1; 30,250 ± 5100 AD-SVFs/mL in SG-2; 33.333 ± 5650 AD-SVFs/mL in SG-3, while 500 AD-SVFs/mL were obtained in CG. In patients treated with A-FG enhanced with AD-SVFs obtained by automatic enzymatic digestion, a 63% ± 6.2% maintenance of fat volume restoring after 1 year was observed compared with 52% ± 4.6% using centrifugation with filtration, 39% ± 4.4% using only centrifugation (Coleman), and 60% ± 5.0% using only filtration.

CONCLUSIONS

In vitro AD-SVFs cell analysis indicated that filtration was the most efficient system-between mechanical digestion procedures-thanks to the highest amount of cells obtained with fewer cell structure damage, producing in vivo, the most volume maintenance after 1 year. Enzymatic digestion produced the best number of AD-SVFs and the best fat volume maintenance.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .

Reply to "Letter on Rhinofiller: Fat Grafting (Surgical) Versus Hyaluronic Acid (Non-surgical)"

Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Strategies to Improve AFT Volume Retention After Fat Grafting

BACKGROUND

Autologous fat grafting has gained increasing popularity used in plastic surgery as a strategy to improve functional and aesthetic outcome. However, variable augmentation results have concerned surgeons in that volume loss of grafted fat reported fluctuates unsteadily.

AIM

An optimal technique that clinically maximizes the long-term survival rate of transplantation is in urgent need to be identified.

METHOD

The PubMed/MEDLINE database was queried to search for animal and human studies published through March of 2022 with search terms related to adipose grafting encompassing liposuction, adipose graft viability, processing technique, adipose-derived stem cell, SVF and others.

RESULTS

45 in vivo studies met inclusion criteria. The principal of ideal processing technique is effective purification of fat and protection of tissue viability, such as gauze rolling and washing-filtration devices. Cell-assisted lipotransfer including SVF, SVF-gel and ADSCs significantly promotes graft retention via differentiation potential and paracrine manner. ADSCs induce polarization of macrophages to regulate inflammatory response, mediate extracellular matrix remodeling and promote endothelial cell migration and sprouting, and differentiate into adipocytes to replace necrotic cells, providing powerful evidence for the benefits and efficacy of cell-assisted lipotransfer.

CONCLUSION

Based on the current evidence, the best strategy can not be decided. Cell-assisted lipotransfer has great potential for use in regenerative medicine. But so far mechanically prepared SVF-gel is conducive to clinical promotion. PRP as endogenous growth factor sustained-release material shows great feasibility.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Immunomodulatory properties of mesenchymal stromal/stem cells: The link with metabolism

BACKGROUND

Mesenchymal stromal/stem cells (MSCs) are the most promising stem cells for the treatment of multiple inflammatory and immune diseases due to their easy acquisition and potent immuno-regulatory capacities. These immune functions mainly depend on the MSC secretion of soluble factors. Recent studies have shown that the metabolism of MSCs plays critical roles in immunomodulation, which not only provides energy and building blocks for macromolecule synthesis but is also involved in the signaling pathway regulation.

AIM OF REVIEW

A thorough understanding of metabolic regulation in MSC immunomodulatory properties can provide new sights to the enhancement of MSC-based therapy.

KEY SCIENTIFIC CONCEPTS OF REVIEW

MSC immune regulation can be affected by cellular metabolism (glucose, adenosine triphosphate, lipid and amino acid metabolism), which further mediates MSC therapy efficiency in inflammatory and immune diseases. The enhancement of glycolysis of MSCs, such as signaling molecule activation, inflammatory cytokines priming, or environmental control can promote MSC immune functions and therapeutic potential. Besides glucose metabolism, inflammatory stimuli also alter the lipid molecular profile of MSCs, but the direct link with immunomodulatory properties remains to be further explored. Arginine metabolism, glutamine-glutamate metabolism and tryptophan-kynurenine via indoleamine 2,3-dioxygenase (IDO) metabolism all contribute to the immune regulation of MSCs. In addition to the metabolism dictating the MSC immune functions, MSCs also influence the metabolism of immune cells and thus determine their behaviors. However, more direct evidence of the metabolism in MSC immune abilities as well as the underlying mechanism requires to be uncovered.

Adipose-derived stem cells applied in skin diseases, wound healing and skin defects: a review

Adipose tissue presents a comparably easy source for obtaining stem cells, and more studies are increasingly investigating the therapeutic potential of adipose-derived stem cells. Wound healing, especially in chronic wounds, and treatment of skin diseases are some of the fields investigated. In this narrative review, the authors give an overview of some of the latest studies concerning wound healing as well as treatment of several skin diseases and concentrate on the different forms of application of adipose-derived stem cells.

The efficacy of cell-assisted versus conventional lipotransfer: A systematic review and meta-analysis

Autologous lipotransfer is an essential component of soft tissue reconstruction. However, it is not widely applied or accepted by surgeons due to its unstable survival rate and uncertain efficacy. The cell-assisted fat transfer (CAL) is a promising technique that increases the fat survival rate. However, it is controversial based on various clinical studies. Here, we assessed the fat survival and complication rates of CAL, compared to the conventional autologous lipotransfer. To conduct our research, two reviewers independently screened related articles published in Medicine (via PubMed), EMBASE, Cochrane Library, and Web of Science. The combined effect estimates for efficacy evaluation was performed by the Review Manager software (RevMan 5.4.1). In total, 14 articles were included in our analysis (n = 722). Based on our analysis, the survival rate of the fat graft in CAL was significantly higher than the conventional fat grafting group (non-CAL group) (SMD = 2.81, 95%CI [1.54, 4.08], P < 0.01). In the subgroup, the fat retention of CAL in the facial filling was higher than the conventional one (SMD = 3.01, 95%CI [1.68, 4.33], P < 0.01). After breast augmentation, however, the difference between the experimental and control group was not statistically significant (SMD = 1.80, 95%CI [-0.31, 3.91], P = 0.09). Moreover, the CAL group exhibited comparable complications as the non-CAL group. Based on our analysis, the CAL group was significantly better than the conventional lipotransfer in terms of fat survival, particularly, during facial filling. However, it failed to reduce the complication rate, compared to the non-CAL group.

Supplementation of Facial Fat Grafting to Increase Volume Retention: A Systematic Review

BACKGROUND

For decades, facial fat grafting has been used in clinical practice for volume restoration. The main challenge of this technique is variable volume retention. The addition of supplements to augment fat grafts and increase volume retention has been reported in recent years.

OBJECTIVES

The aim of this systematic review was to investigate which supplements increase volume retention in facial fat grafting as assessed by volumetric outcomes and patient satisfaction.

METHODS

Embase, Medline, Ovid, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, and Google Scholar were searched up to November 30, 2020. Only studies assessing volume after facial fat grafting with supplementation in human subjects were included. Outcomes of interest were volume or patient satisfaction. The quality of the studies was assessed with the Effective Public Health Practice Project tool.

RESULTS

After duplicates were removed 3724 studies were screened by title and abstract. After reading 95 full-text articles, 27 studies were eligible and included for comparison. Supplementation comprised of platelet-rich plasma, platelet-rich fibrin, adipose tissue-derived stromal cells or bone marrow-derived stromal cells, cellular or tissue stromal vascular fraction, or nanofat. In 13 out of 22 studies the supplemented group showed improved volumetric retention and 5 out of 16 studies showed greater satisfaction. The scientific quality of the studies was rated as weak for 20 of 27 studies, moderate for 6 of 27 studies, and strong for 1 study.

CONCLUSIONS

It remains unclear if additives contribute to facial fat graft retention and there is a need to standardize methodology.

LEVEL OF EVIDENCE: 4

Rhinofiller: Fat Grafting (Surgical) Versus Hyaluronic Acid (Non-Surgical)

BACKGROUND

The author presented his experience using "fat grafting" (FG) and "hyaluronic acid" (HA) techniques in nasal remodeling.

OBJECTIVES

The paper aimed to evaluate the efficacy and safety of the use of FG and HA in nasal remodeling for aesthetic improvement.

METHODS

A randomized controlled trial was conducted. 15 patients affected by soft defects of the dorsum, low and boxy nasal tip, and hidden columella, were treated with FG (study group-SG), comparing results with the control group (CG) (n = 17) treated with hyaluronic acid (HA). Post-operative follow-up took place at 1, 2, 4, weeks, 3, 6, 12 months, and then annually.

RESULTS

73.7% of SG patients showed excellent cosmetic results after 1 year compared with only 29.7% of CG patients. At one-month, major part of people who underwent the treatments (FG and HA) referred to satisfaction with the resulting volume contours (p = 0.389). 88.3% of CG patients versus 53.8% of SG described the HA and FG injection, respectively, as a very comfortable and non-invasive procedure. As expected, patient satisfaction with the appearance of nasal contouring was higher in the FG group at 1 year.

CONCLUSIONS

FG and HA were safe and effective in this series of cases performed.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Effects of miR126 Expressing Adipose-Derived Stem Cells on Fat Graft Survival and Angiogenesis

BACKGROUND

Fat transplantation supported by supplementation with ASCs has become a reliable procedure for treating soft tissue defects. However, the unpredictable survival rates for grafted fat remains a challenge with post-transplantation ischemia causing tissue loss. MiR126, which regulates VEGF signaling, is an endothelial cell-specific miRNA known to play an essential role in angiogenesis. We hypothesized that increased miR126 expression in grafted ASCs may promote fat survival within an autologous fat transfer model.

METHODS

Rat adipose-derived stem cells were isolated, expanded ex vivo for three passages and then transduced with miR126. We used PCR to verify lentiviral transduction and ELISA to confirm VEGF expression. We then mixed autologous fat tissues from our rat model with transduced ASCs, augmented with a nonsense control or miR126 expression vector. These mixtures were used in the fat grafting procedure, completed via subcutaneous injection at three paravertebral points in each rat. Fat grafts were then harvested on days 4, 7, 14, and 28 post-transplant and evaluated for survival, neovascularization, and protein expression via western blot.

RESULTS

VEGF expression levels in ASCs, Con-ASCs, and miR126-ASCs were not significantly different. However, miR126-ASCs experienced significantly improved survival on days 7, 14, and 28 when compared with the other groups. These ASCs also presented with the greatest capillary density on days 7, 14, and 28 post-transplantation as well as increased p-ERK and p-AKT expression when compared to the other groups.

CONCLUSION

This data suggests that miR126 augmentation of ASCs may help to enhance the survival and angiogenic capacity of transplanted fat tissues, and that this augmentation was not dependent on VEGF but rather the activation of the ERK/AKT pathway.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The investigation of the efficacy and safety of stromal vascular fraction in the treatment of nanofat-treated acne scar: a randomized blinded controlled clinical trial

Background

Acne is the most common skin disorder which is known as a chronic inflammatory disease with psychological burden and reduced quality of life. Adipose tissue-derived stromal vascular fraction (SVF) is recognized as a source of regenerative cells and improves the quality of skin by increasing collagen content. To date, a few studies have been performed on the therapeutic role of SVF in the treatment of acne scars.

Methods

This randomized, single-blinded clinical trial was performed on 7 patients with acne scars. In all patients, the initial grade of acne (volume, area and depth) was evaluated and ultrasound of the relevant scar was performed to evaluate neocollagenesis. As a spilt face study, for treating the scars, we used nanofat subcutaneously on one side of the face (control group) and combination of nanofat subcutaneously and SVF intradermally on the opposite side (intervention group). The patients were evaluated for severity of acne by visioface after one month, also for thickness of epidermis and dermis by ultrasound after one month and three months.

Results

All of the apparent findings of scars improved in two groups after one month, but these changes were significant just for the group treated with SVF (p value < 0.05). Epidermal, dermal and complete thicknesses during the first month in both control and intervention groups were significantly increased (p value < 0.05) but between the first and third months, there was no significant difference in the variables (p value > 0.05). The findings showed that dermal and complete thicknesses of the skin in the first month were different between two groups significantly (p value: 0.042 and 0.040, respectively).

Conclusion

The use of SVF in the treatment of patients with acne scars accelerates the improvement of volume, area and depth of the scar by increasing collagen content and the dermal thickness, so it can be used as a potentially effective treatment for these patients.

Bone marrow mesenchymal stem cells facilitate diabetic wound healing through the restoration of epidermal cell autophagy via the HIF-1α/TGF-β1/SMAD pathway

BACKGROUND

The biological activity and regenerative medicine of bone marrow mesenchymal stem cells (BMSCs) have been focal topics in the broad fields of diabetic wound repair. However, the molecular mechanisms are still largely elusive for other cellular processes that are regulated during BMSC treatment. Our previous studies have shown that hypoxia is not only a typical pathological phenomenon of wounds but also exerts a vital regulatory effect on cellular bioactivity. In this study, the beneficial effects of hypoxic BMSCs on the cellular behaviors of epidermal cells and diabetic wound healing were investigated.

METHOD

The viability and secretion ability of hypoxic BMSCs were detected. The autophagy, proliferation and migration of HaCaT cells cultured with hypoxic BMSCs-derived conditioned medium were assessed by estimating the expression of autophagy-related proteins, MTS, EdU proliferation and scratch assays. And the role of the SMAD signaling pathway during hypoxic BMSC-evoked HaCaT cell autophagy was explored through a series of in vitro gain- and loss-of-function experiments. Finally, the therapeutic effects of hypoxic BMSCs were evaluated using full-thickness cutaneous diabetic wound model.

RESULTS

First, we demonstrated that hypoxic conditions intensify HIF-1α-mediated TGF-β1 secretion by BMSCs. Then, the further data revealed that BMSC-derived TGF-β1 was responsible for the activation of epidermal cell autophagy, which contributed to the induction of epidermal cell proliferation and migration. Here, the SMAD signaling pathway was identified as downstream of BMSC-derived TGF-β1 to regulate HaCaT cell autophagy. Moreover, the administration of BMSCs to diabetic wounds increased epidermal autophagy and the rate of re-epithelialization, leading to accelerated healing, and these effects were significantly attenuated, accompanied by the downregulation of Smad2 phosphorylation levels due to TGF-β1 interference in BMSCs.

CONCLUSION

In this report, we present evidence that uncovers a previously unidentified role of hypoxic BMSCs in regulating epidermal cell autophagy. The findings demonstrate that BMSC-based treatment by restoring epidermal cell autophagy could be an attractive therapeutic strategy for diabetic wounds and that the process is mediated by the HIF-1α/TGF-β1/SMAD pathway.

Emerging treatment strategies in wound care

Wound healing is a complex process in tissue regeneration through which the body responds to the dissipated cells as a result of any kind of severe injury. Diabetic and non-healing wounds are considered an unmet clinical need. Currently, different strategic approaches are widely used in the treatment of acute and chronic wounds which include, but are not limited to, tissue transplantation, cell therapy and wound dressings, and the use of an instrument. A large number of literatures have been published on this topic; however, the most effective clinical treatment remains a challenge. The wound dressing involves the use of a scaffold, usually using biomaterials for the delivery of medication, autologous stem cells, or growth factors from the blood. Antibacterial and anti-inflammatory drugs are also used to stop the infection as well as accelerate wound healing. With an increase in the ageing population leading to diabetes and associated cutaneous wounds, there is a great need to improve the current treatment strategies. This research critically reviews the current advancement in the therapeutic and clinical approaches for wound healing and tissue regeneration. The results of recent clinical trials suggest that the use of modern dressings and skin substitutes is the easiest, most accessible, and most cost-effective way to treat chronic wounds with advances in materials science such as graphene as 3D scaffold and biomolecules hold significant promise. The annual market value for successful wound treatment exceeds over $50 billion US dollars, and this will encourage industries as well as academics to investigate the application of emerging smart materials for modern dressings and skin substitutes for wound therapy.

Efficacy of topical and systemic transplantation of mesenchymal stem cells in a rat model of diabetic ischemic wounds

BACKGROUND

Mesenchymal stem cells (MSCs) exert positive effects in chronic wounds. However, critical parameters, such as the most effective administration routes, remain unclear. Accordingly, the purpose of this study was to compare the effects of topical and systemic transplantation MSCs on diabetic ischemic wound healing and explored the underlying mechanisms.

METHOD

A diabetic ischemic wound model was created on the dorsal foot of type 2 diabetes mellitus (T2DM) rat. Bone marrow-derived mesenchymal stem cells (BM-MSCs) were administered via two routes: topical injection and intravenous (IV) infusion. Wound healing outcomes and blood glucose level were assessed dynamically. Meanwhile, blood flow recovery was evaluated in ischemic gastrocnemius muscles. The homing and transdifferentiation of mKate2-labeled BM-MSCs were assessed by fluorescence imaging and immunohistochemistry (IHC) analysis.

RESULT

Both topical and systemic treatments had a positive effect on the diabetic ischemic wound showing a significant reduction in wound area at day 14. Histological results showed an increase in the length of epithelial edges, collagen content, microvessel density in the wound bed, and a higher expression of vascular endothelial growth factor (VEGF). Meanwhile, systemic administration can ameliorate hyperglycemia and improve the blood perfusion of the ischemic hindlimb. BM-MSCs administered systemically were found distributed in wounded tissue and transdifferentiated into endothelial cells. Furthermore, BM-MSCs stimulated angiogenesis at wound sites by downregulating phosphatase and tensin homolog (PTEN) and activation of AKT signaling pathway.

CONCLUSIONS

The results demonstrated that both transplantation delivery method (topical and systemic) of BM-MSCs accelerated wound healing remarkably under pathological conditions. Nevertheless, systemic administration has the potential to ameliorate hyperglycemia and repair the damaged tissue.

Systematic Review: Adipose-Derived Mesenchymal Stem Cells, Platelet-Rich Plasma and Biomaterials as New Regenerative Strategies in Chronic Skin Wounds and Soft Tissue Defects

The number of clinical trials evaluating adipose-derived mesenchymal stem cells (AD-MSCs), platelet-rich plasma (PRP), and biomaterials efficacy in regenerative plastic surgery has exponentially increased during the last ten years. AD-MSCs are easily accessible from various fat depots and show intrinsic plasticity in giving rise to cell types involved in wound healing and angiogenesis. AD-MSCs have been used in the treatment of soft tissue defects and chronic wounds, employed in conjunction with a fat grafting technique or with dermal substitute scaffolds and platelet-rich plasma. In this systematic review, an overview of the current knowledge on this topic has been provided, based on existing studies and the authors’ experience. A multistep search of the PubMed, MEDLINE, Embase, PreMEDLINE, Ebase, CINAHL, PsycINFO, Clinicaltrials.gov, Scopus database, and Cochrane databases has been performed to identify papers on AD-MSCs, PRP, and biomaterials used in soft tissue defects and chronic wounds. Of the 2136 articles initially identified, 422 articles focusing on regenerative strategies in wound healing were selected and, consequently, only 278 articles apparently related to AD-MSC, PRP, and biomaterials were initially assessed for eligibility. Of these, 85 articles were excluded as pre-clinical, experimental, and in vitro studies. For the above-mentioned reasons, 193 articles were selected; of this amount, 121 letters, expert opinions, commentary, and editorials were removed. The remaining 72 articles, strictly regarding the use of AD-MSCs, PRP, and biomaterials in chronic skin wounds and soft tissue defects, were analyzed. The studies included had to match predetermined criteria according to the patients, intervention, comparator, outcomes, and study design (PICOS) approach. The information analyzed highlights the safety and efficacy of AD-MSCs, PRP, and biomaterials on soft tissue defects and chronic wounds, without major side effects.

Mesenchymal stem cells and exosome therapy for COVID-19: current status and future perspective

Acute respiratory distress syndrome (ARDS) is the main cause for the COVID-19 infection-related morbidity and mortality. Recent clinical evidences suggest increased level of cytokines and chemokines targeting lung tissue as a prominent etiological factor. The immunomodulatory effect of mesenchymal stem cells (MSCs) as the alternative therapy for the treatment of inflammatory and autoimmune diseases is well known. Several studies have also revealed that similar therapeutic impacts of parent MSCs are also exhibited by MSCs-derived extracellular vesicles (EVs) including exosomes. In this review, we explored the therapeutic potential of both MSCs and exosomes in mitigating the COVID-19 induced cytokine storm as well as promoting the regeneration of alveolar tissue, attributed to the intrinsic cytokines and growth factor present in the secretome. The preliminary studies have demonstrated the safety and efficacy of MSCs and exosomes in mitigating symptoms associated with COVID-19. Thus, they can be used on compassionate basis, owing to their ability to endogenously repair and decrease the inflammatory reactions involved in the morbidity and mortality of COVID-19. However, more preclinical and clinical studies are warranted to understand their mechanism of action and further establish their safety and efficacy.