Platelet-Rich Fibrin in Fat Grafts for Facial Lipofilling: A Randomized, Controlled Split-Face Clinical Trial

Objective

Previous studies have reported that platelet-rich fibrin (PRF) may enhance the efficacy of fat grafts in facial lipofilling. However, these studies either lacked objective data or were not randomized, controlled trials. Thus, we aimed to objectively evaluate the efficacy of PRF in facial lipofilling.

Methods

A controlled, split-face, randomized trial (January 2018 to May 2019) based on 18 patients who underwent fat grafts for bilateral temple lipofilling was performed. Each patient received a combination of an autologous fat graft and PRF on one side and a fat graft combined with an equal volume of saline on the other side. The effects of PRF were evaluated by comparing the remaining bilateral fat graft volumes through a digital three-dimensional reconstruction technique. Improvements in the appearance and recovery time of each temple were assessed by both a surgeon and patients who were blinded to the treatment assignment. Complications were also recorded.

Results

Bilateral temple lipofilling showed no evidence of fat embolism, vascular/nerve injury, infection, massive edema, or prolonged bruising. Three-dimensional reconstruction data and the assessments from both the surgeon and patients revealed no significant differences in fat graft retention volume between the PRF-positive and PRF-negative lipofilling groups. However, recovery time in the PRF-positive lipofilling sites was significantly shortened compared with that of the PRF-negative lipofilling sites.

Conclusion

Facial filling with autologous fat grafts is effective and safe. Our results show that PRF does not markedly improve fat graft volume retention in the temple but significantly reduces postoperative recovery time.

Trial Registration Number

ChiCTR2100053663.

[Explorative study of the immobilizing effect of full-thickness skin subcutaneous grafting on allogeneic full-thickness skin graft in rats]

Objective: To investigate the immobilizing effect of full-thickness skin subcutaneous grafting on allogeneic full-thickness skin graft in rats. Methods: The experimental research method was used. The inbred male Brown-Norway rats (n=10) and Lewis rats (n=10) were used as donors and recipients respectively. After subcutaneously full-thickness separation of a 2.2 cm×2.2 cm area on the nape of the recipient rat, a full-thickness skin of 2.0 cm×2.0 cm taken from the abdomen of the donor rat was subcutaneously grafted, and the donor site was pulled together and sutured. The autologous skin over the allograft in the recipient rat was excised 5-6 d after grafting, and the stitches were removed 7 d after excision. Within 2 months after grafting, the feeding, activity, and survival of the donor and recipient rats, behavior of tearing and scratching the wounds of the recipient rats, the wound condition after autologous skin excision in recipient rats, and the survival and hair growth of the grafted allogeneic skin were observed. Results: Within 2 months after grafting, the donor and recipient rats all ate normally and could move freely with no abnormal death. No tearing or scratching of the wounds occurred in recipient rats. There was a small amount of exudation and partial epidermal desquamation after autologous skin excision in recipient rats. All transplanted allografts survived, which were free of infection and necrosis, with new hairs growing out smoothly. Conclusions: The immobilizing method of full-thickness skin subcutaneous grafting of allogeneic full-thickness skin graft in rats is simple and time-saving without postoperative dressing change, with reliable pressure fixation and high survival rate of skin grafts, which can be promoted for animal skin grafting models.

Decellularized adipose matrix provides an inductive microenvironment for stem cells in tissue regeneration

Stem cells play a key role in tissue regeneration due to their self-renewal and multidirectional differentiation, which are continuously regulated by signals from the extracellular matrix (ECM) microenvironment. Therefore, the unique biological and physical characteristics of the ECM are important determinants of stem cell behavior. Although the acellular ECM of specific tissues and organs (such as the skin, heart, cartilage, and lung) can mimic the natural microenvironment required for stem cell differentiation, the lack of donor sources restricts their development. With the rapid development of adipose tissue engineering, decellularized adipose matrix (DAM) has attracted much attention due to its wide range of sources and good regeneration capacity. Protocols for DAM preparation involve various physical, chemical, and biological methods. Different combinations of these methods may have different impacts on the structure and composition of DAM, which in turn interfere with the growth and differentiation of stem cells. This is a narrative review about DAM. We summarize the methods for decellularizing and sterilizing adipose tissue, and the impact of these methods on the biological and physical properties of DAM. In addition, we also analyze the application of different forms of DAM with or without stem cells in tissue regeneration (such as adipose tissue), repair (such as wounds, cartilage, bone, and nerves), in vitro bionic systems, clinical trials, and other disease research.

Transconjunctival Orbital Septum Fat Release and Preservation for Orbitopalpebral Sulcus in Lower Eyelid Blepharoplasty

BACKGROUND

Compared to the traditional transcutaneous approach, a safe and effective lower eyelid blepharoplasty has been recognized. In 2007, Sadove first reported a series of patients treated with transconjunctival septal suturing, but the inferior orbitopalpebral sulcus was not totally improved.

PURPOSE

Orbital septal fat release and preservation through the transconjunctival approach was used to treat 20 young patients with bulging bags and inferior orbitopalpebral sulcus.

METHOD

The orbital septal fat was released and transferred to infraorbital rim to be a base for the inferior orbitopalpebral sulcus.

RESULT

Obvious bulging fat was released, and the orbitopalpebral sulcus was flattened by released and excessive orbital septal fat. Satisfactory results were achieved.

CONCLUSION

The results achieved from this series of patients indicate that orbital septal fat release and preservation through the transconjunctival approach for reducing the orbitopalpebral sulcus is a safe and effective treatment for bulging fat and orbitopalpebral sulcus in young patients.

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 .

[Establishment of new vessels model by implantation of VEGF165 in mouse]

OBJECTIVE

To investigate the feasibility of establishing a murine new vessels model with Lentiviral vector (LVs) mediated human vascular endothelial growth factor-165 (pcDNA3.1/ VEGF165) gene.

METHODS

Lentivirus plasmid carrying a human VEGF165 was constructed and was used to transfect mouse's NIH/3T3 cells. The NIH/3T3 cells with high secretion of VEGF were injected into the skeletal muscle of mouse to establish a mouse new vessels model by implantation of vascular endothelium growth factor (VEGF) gene. The external secretion of VEGF was measured with ELISA. Histological examination was carried out after injection. The expression of CD31 was assessed with immunohistochemical method.

RESULTS

The lenti-VEGF165-EGFP was correctly constructed and confirmed by restriction endonuclease analysis, polymerase chain reaction and DNA sequencing analysis. Lentivirus plasmid carrying a human VEGF165 was constructed. lenti-VEGF165-EGFP was used to transfect mouse's NIH/ 3T3 cells, and human VEGF165 gene was assessed. NIH/3T3 cells mediated VEGF gene implantation can produce stable and effective mouse new vessels model. The external secretion of VEGF in peripheral blood was measured with ELISA. The legs became swollen in experimental group 14 d after injection. It found the cells expression of CD31 44 d after injection, and histological analysis showed the swollen tissue was composed of small new vessels.

CONCLUSIONS

NIH/3T3 cells mediated VEGF gene implantation can produce stable and effective mouse new vessels model.

Trichostatin A inhibits collagen synthesis and induces apoptosis in keloid fibroblasts

Keloid, a fibro-proliferative benign tumor of skin, is characterized by an enriched milieu of growth factors and an abundant accumulation of extracellular matrix (ECM). Transforming growth factor (TGF)-β1 is well known as the crucial fibrogenic cytokine promoting ECM production and tissue fibrosis in keloid forming. Epigenetic modifications have been shown to play a role in the pathogenesis of cancer as well as autoimmune and inflammatory disorders. Recent publication reports epigenetic modifications in keloid fibroblasts that include an altered pattern of DNA methylation and histone acetylation. Therefore, the field of epigenetics may provide a new therapeutic idea for keloid treatment strategies. Currently, there is some evidence from experimental studies that histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) causes abrogation of TGF-β1 induced collagen synthesis in skin fibroblasts. Furthermore, TSA could suppress proliferation and induce apoptosis in a broad spectrum of tumor cells both in vitro and in vivo. These findings suggest that TSA could also cause abrogation of TGF-β1 induced collagen synthesis and induce apoptosis of proliferating keloid fibroblasts.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist inhibits transforming growth factor-beta1 and matrix production in human dermal fibroblasts

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists are increasingly used in patients with diabetes, and some studies have suggested a beneficial effect on organ fibrosis, but their effects on dermal cell growth and extracellular matrix (ECM) turnover are unknown. To investigate the effect of the PPAR-gamma agonist troglitazone on cell growth and matrix production in human dermal fibroblasts (HDF), HDF were cultured and grown in a different concentration of troglitazone. PPAR-gamma expression and matrix production were measured in HDF in the presence of troglitazone. The mRNA expressions of TGF-beta1, collagen I (Col I) and fibronectin (FN) were determined by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). The protein of transforming growth factor-beta1 (TGF-beta1) was determined by enzyme-linked immunosorbent assay (ELISA) and proteins of Col I and FN were determined by Western blotting. The mRNA expression of TGF-beta1, Col I and FN were significantly decreased in HDF in 15-30 micromol l(-1) troglitazone compared to the control group with Dulbecco's modified Eagle's medium (P<0.01). An obvious decrease of TGF-beta1 protein was found in troglitazone-treated groups as compared to the control group (P<0.05). Exposure of HDF to troglitazone reduced col I secretion (P<0.05), and fibronectin secretion (P<0.05). This study suggests that PPAR-gamma agonist will provide a novel approach with therapeutic potential in dermal fibrosis, such as hypertrophic scar, keloid and so on.

Infantile hemangioma is originated from placental trophoblast, fact or fiction?

Infantile hemangiomas are common, benign tumors, distinctive for their perinatal presentation, rapid growth and subsequent involution. Hemangiomas can pose serious concerns to the cosmetic and psychosocial development of the afflicted child, but none of the current therapeutic modalities is ideal to date, partly because the origin of the pathogenic ECs in infantile hemangioma is unknown. Many clues and evidences suggest a link between infantile hemangiomas and the maternal placental trophoblasts. Shared expression of distinct endothelial markers in hemangioma and placental tissues raises a possibility that infantile hemangioma is originated from placental trophoblast. Moreover, the findings of a very high similarity between the transcriptomes of placenta and hemangioma provide strong support for this theory. Furthermore, epidemiologic and clinical evidences accumulated in recent years also suggest the placental trophoblast as the cell of origin for infantile hemangioma. These findings imply a unique relationship between hemangioma and the placental trophoblast and suggest a hypothesis that infantile hemangioma is originated from placental trophoblast. The hypothesis could provide new understanding of these vascular tumors of childhood and may become the most promising research fields for the etiology of infantile hemangiomas. Further study of the precise mechanisms for the placental trophoblast originated hemangiomas will produce new preventive strategies and therapeutic avenues, possibly immunologic treatment, to the very difficult problem.

Possibilities and potential roles of estrogen in the pathogenesis of proliferation hemangiomas formation

Hemangiomas, often categorized as angiogenic diseases, are the most common tumors of infancy, the life span of which is generally divided into proliferating phase, involuting phase, and involuted phase. Despite their high prevalence, the mechanism leading to proliferation hemangiomas formation is poorly understood and the best approach to their management remains controversial. None of the current therapeutic modalities is ideal, partly because the pathogenesis of hemangioma and the mechanism of its proliferation are far from clear. Many clues reveal that estrogen has an important role in developing the vascular system, experimental and clinical evidences accumulated in recent years also suggest the potential for estrogen to influence neovascularization. Based on those, we hypothesize that estrogen play a potential role in the development of hemangiomas, mainly by regulating some key angiogenic factors, including MMP-9, EPCs, VEGF, NO, etc. Accepting the hypothesis to be correct, a therapy that identify estrogen as a potential target for the design of new, more specific treatments can be used to prevent the proliferation hemangiomas formation. The hypothesis may lead a new direction in the study of mechanisms for proliferation hemangiomas formation, and further study of the precise mechanisms for estrogen-induced hemangiomas will produce effective antiestrogens and estrogen receptor antagonists as new medication for the very difficult problem.

Proliferation hemangiomas formation through dual mechanism of vascular endothelial growth factor mediated endothelial progenitor cells proliferation and mobilization through matrix metalloproteinases 9

Infantile hemangioma is the most common tumor of infancy and the mechanism leading to proliferation hemangiomas formation is poorly understood and currently no successful treatment modality exists. We hypothesize that EPCs formed during proliferation hemangiomas, as the result of vascular endothelial growth factor (VEGF) stimulation through MMP9, play the major role in the control of cell proliferation and capillary-like vessels production. Accepting the hypothesis to be correct, a therapy that inhibits EPC mobilization and proliferation can be used to prevent the proliferation hemangiomas formation. Current therapies are only partially effective and safe because they could not eliminate all the relative factors of proliferation hemangiomas formation at all, such as: EPCs in the peripheral blood, and at the same time inducing death (apoptosis and necrosis) of other normal cells. A more efficient prevention of proliferation hemangiomas could be achieved using specific drugs or biologic methods that inhibit EPC mobilization and proliferation. Therapy based on gene therapy, capable to specifically inhibit VEGF and MMP9 expression in gene level, can be possibly effective.

VEGF gene therapy for the survival of transplanted fat tissue in nude mice

The objective of this study was to determine the effects of adenovirus-mediated vascular endothelial growth factor (Ad-VEGF) on the angiogenesis and survival of free-fat tissue transplantation in nude mice. Thirty 6-week-old CD-1 nude male mice were injected with 1ml fat tissue (harvested by suction-assisted lipectomy from the breast of humans) in the subcutaneous of scalp and were randomised into three groups of 10 animals each. Group 1 was the study group, in which Ad-VEGF was mixed with transplanted fat tissue and injected into mice. In group 2, adenovirus-mediated green fluorescent protein (Ad-GFP) gene was mixed with transplanted fat tissue and injected into the mice. In group 3, normal saline alone was used. Both group 2 and group 3 are control groups. The animals were euthanised 15 weeks after the procedure. The fat survival weight and volume of the study group were significantly greater than those of two control groups (p<0.05). Light microscopical examination of haematoxylin and eosin-stained slides of the dissected fat 15 weeks after injection was performed in group 1 and group 2. Less cyst formation and fibrosis, indicating improved quality of the injected fat, can be obtained by the addition of Ad-VEGF. Vascular density was evaluated at the microvascular level through the use of light microscopic sections of the central part of the fat tissue at 15 weeks after injection by von Willebrand factor staining. Histological evaluation showed that capillary density increased markedly in the study group mice. Mice of the study group disclosed significantly higher VEGF protein levels detected by ELISA assay of plasma samples obtained from the mice after the fat injection (day 1, 4, 7 and 28; p<0.01) at each time point than the mice of the two control groups. The findings reported in this study indicate that the VEGF gene therapy can enhance the survival and the quality of grafted fat tissue, which may be due to induction of angiogenesis.

[Promotion of the survival of ischemic skin flap by transplanted endothelial progenitor cells transfected with VEGF165 gene: an experimental study with mice]

OBJECTIVE

To investigate the feasibility of transplanted endothelial progenitor cells transfected with VEGF165 gene to ischemic flap with increased neovascularization and augmented the survival areas.

METHODS

EPCs were isolated from human cord blood and cultured in vitro. Plasmid PcDNA3.1(-)/VEGF165 containing VEGF gene was transfected into the EPCs. EPCs transfected with blank plasmid, and EPCs without transfection were used as controls. ELISA was used to detect the expression of VEGF protein in the culture fluids. The EPCs were dyed with CM-DiI 7 days later. Ischemic skin flaps were made on the backs of 27 nude mice. The mice were randomly divided into 3 equal groups with their skin flaps being transplanted with EPCs transfected with 3.1(-)/VEGF165 plasmid, EPCs not transfected with 3.1(-)/VEGF165 plasmid, and injected with M199 medium at the basal part. Four days after the peduncles of the skin flaps were cut. Seven days after the cutting-off of the peduncles the survival rate of skin flap was observed and the blood perfusion was observed with laser Doppler flowmetry, 10 days after the density of capillary arteries were observed with microcirculation microscope. Three specimens of skin flap were taken 7 and 11 days after the skin flaps were made to undergo histological examination to detect the density of capillary arteries by CD34 immunohistochemistry and to observe the proliferation of EPCs with fluorescence microscopy. Peripheral blood samples were collected 1, 4, 7, 14, and 28 days after the skin flaps were made to undergo ELISA to detect the levels of VEGF protein

RESULTS

The VEGF levels in the culture supernatants of the groups A, B, and C were 352 ng/L +/- 35 ng/L, 45 ng/L +/- 5 ng/L, and 0 ng/L respectively with significant difference between any 2 groups (all P < 0.05). The skin flap survival rates of the three groups were 97.2%, 60.3%, and 34.2% respectively with significant difference between any 2 groups (all P < 0.05) and the survival quality of the group A was the best. The capillary density of the group A was greater than those of the groups B and C. The VEGF levels at any time point of the group A were all significantly higher than those of the group B and C (all P < 0.05) and there was not a significant difference between the groups B and C. The capillary density levels at different time points decreased progressively in the order of groups A, B, and C with significant difference between any 2 groups (all P < 0.05). No EPC was shown by fluorescence microscopy in the skin flaps of the group C. The EPC density in skin flap 7 and 11 days after the flaps were made were 136 +/- 10 and 75 +/- 6/mm(2) and 305 +/- 26 and 199 +/- 18/mm(2) respectively with significant differences between the groups A and B. (both P < 0.05).

CONCLUSION

The EPCs from human cord blood, especially those transfected with VEGF165 gene increases the neovascularization in ischemic skin flaps and augments their survival rate.