Advancing Standardization in Fat Graft Survival Studies: Assessing the Superiority of Paraepididymal Fat Graft as a Donor Site.

BACKGROUND: There is currently no standardization in the field of research on fat grafts in rats, which is one of the most popular topics in plastic surgery. The aim of our study was to demonstrate the effects of selecting paraepididymal fat grafts as the donor area on enhancing the reliability of fat graft studies. METHODS: In this study, 12 male Sprague-Dawley rats were used to obtain adipose grafts from both inguinal and paraepididymal regions. After measuring the graft weights, they were subjected to histological examination using hematoxylin-eosin staining, as well as immunohistochemical staining with antiperilipin antibody. Purity of the samples, viability of adipose cells, and the presence of lymph nodes within the grafts were analyzed. RESULTS: The purity of adipose cells in graft samples obtained from the paraepididymal region was found to be 98.1% compared with the total sample. In contrast, the purity of adipose cells in graft samples obtained from the inguinal region was 58.37%. Hematoxylin-eosin staining revealed significantly higher adipocyte viability and vascularity in the paraepididymal region compared with the inguinal region (P = 0.0134). Conversely, lymphatic tissue content in samples obtained from the inguinal region was significantly higher compared with paraepididymal adipose tissue samples (P < 0.0001). Immunohistochemical staining with antiperilipin antibody showed a denser and more uniform staining pattern in paraepididymal adipose grafts (P < 0.0001). CONCLUSIONS: Using paraepididymal fat, devoid of lymphatic tissue, naturally eliminates 2 critical biases (estrogen and lymphatic tissue), enhancing the standardization and reliability of fat graft survival studies.

Effects of Oleuropein Oral Intake on Infected Fat Grafts: Experimental Study.

AIM: The aim of this study was to evaluate the effects of oleuropein oral intake on infected fat grafts and fat graft survival. MATERIALS AND METHODS: 32 Wistar albino rats were divided into four groups: 0. none treated, 1. serum oral intake, 2. antibiotic oral intake, and 3. oleuropein oral intake. The dorsal regions of the rats were separated into four quadrants as right and left cranial, and right and left caudal to determine each quadrant where fat grafts were placed. Right cranial and caudal quadrants were infected with the methicillin-susceptible Staphylococcus aureus (MSSA) strain. The left cranial and caudal quadrants were infected with the Pseudomonas aeruginosa strain. On the 7th day and end of the 3rd month, fibroblast density, inflammation, and fat survival were demonstrated immunohistochemically with FGF, CD68, and perilipin (PP), respectively. RESULTS: On the 7th day, for P. aureginosa-infected grafts, oleuropein was shown higher rates in CD68 and PP staining compared to the antibiotic group (p < 0.05, p < 0.001, respectively). At the end of the 3rd month, for P. aureginosa and S. aureus-infected grafts, the oleuropein group was demonstrated improved PP staining rates compared to the antibiotic group (p < 0.01, p < 0.01, respectively). CONCLUSION: Oleuropein as a natural olive leaf extract with potent antioxidant, anti-inflammatory, and antimicrobial features is an alternative and supportive agent for both treatment and prophylaxis of surgical site infections like the antibiotics of chemical synthesis. P. aeruginosa and S. aureus surgical site infections could treat and prevent safely and effectively by oleuropein, particularly in early and late periods after surgery. 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 .

An immunohistochemical and biomechanical evaluation of the effect of fat graft on tendon healing.

AIM: To investigate the efficacy of fat grafting in primary tendon healing through immunohistochemical and biomechanical examinations. MATERIAL AND METHOD: The study material comprised a total of 10 male Sprague-Dawley rats, each approximately 10 weeks old. All 10 rats were operated on bilaterally. The right Achilles tendon in all the animals was defined as the study group. The tendon was cut and then repaired, and then fat graft was applied to the repair area. The left Achilles tendon of all the rats constituted the control group. The tendon was cut and repaired with no further application. After 4 weeks, the rats were euthanised and samples were taken from the tendons for immunohistochemical and biomechanical examinations. RESULTS: In the biomechanical evaluations, no statistically significant difference was determined between the groups in respect of peak load and stiffness values (p: .068, p: .089, respectively). In the histopathological evaluation, the tenocyte value of the study group was superior to that of the control group (p: .04). No statistically significant differences were determined between the groups in respect of the other histopathological parameters. In the immunohistochemical evaluations, the type I collagen and TGF values of the study group were found to be higher than those of the control group (p: .011, p: .012, respectively). CONCLUSION: Compared to stem cell applications, the use of fat grafting is clinically easy to apply, has low costs, and has been shown to contribute to tendon healing at an immunohistochemical level with increased collagen and TGF beta values.

Increased Total Antioxidant Capacity Value Improves Survival of Fat Grafts in a Rat Model.

BACKGROUND: While studies aiming to increase fat graft survival continue, in this study, we aimed to investigate the effects of different antioxidants on total antioxidant capacity and their effect on graft survival. METHODS: Thirty-two male Wistar rats were divided into four equally sized groups, including a control group and three antioxidant groups receiving either Melatonin (10mg/kg), Zinc (2mg/kg), or Vitamin E and C (100mg/kg). Autologous fat grafts (1.7± 0.4gr) were transferred to the dorsal subcutaneous region, and total antioxidant capacity was measured on day 0 and 1, week 1 and monthly until the third month. Transferred graft volume and mass (1.3± 0.4gr) were measured using the liquid overflow method and precision scales at the end of the study. Routine hematoxylin-eosin staining and immunohistochemistry against perilipin were performed for semiqualitative analysis and h-score for viable adipose cells, respectively. RESULTS: Collected fat grafts measured significantly less in weight and volume and the survival rate was lower in the control group (p<0.01). Control group exhibited a reduction in TAC, while all groups receiving antioxidants had an increase in TAC during the first week (p=0.02, 0.008, and 0.004 for melatonin, zinc, and vitamins, respectively). Immunohistochemistry of the antioxidant group demonstrated a statistically significant excess and reactivity of cells staining with perilipin antibodies. CONCLUSIONS: In this animal study, the beneficial effect of antioxidants on fat graft survival can be related to the significant increase in TAC following the first week of their administration.

Evaluation of the Effect of Metoprolol Dosage on Fat Graft Survival.

AIM: The aim of this study was to evaluate the effect of different metoprolol doses on fat graft survival. MATERIAL AND METHOD: A total of 10 Sprague-Dawley rats were used in the study. The dorsal regions of the rats were separated into four quadrants: right and left cranial, and right and left caudal. Each quadrant was determined as a separate group. Fat grafts were harvested from the groin areas and incubated in 5 ml solutions containing 0.9% sodium chloride (control group), 1 mg/mL metoprolol (Group 1), 2 mg/mL metoprolol (Group 2), and 3 mg/mL metoprolol (Group 3), respectively. The fat grafts were then placed in pockets dissected in each of the 4 dorsal quadrants. After 3 months all the rats were euthanized. The fat grafts were removed together with the surrounding area to which they had passed. Histopathological examination was made with hematoxylin and eosin (HE) and Masson Trichrome staining, and immunohistochemical examination with fibroblast growth factor-2 and perilipin staining. RESULTS: In the examinations made with HE and Masson Trichrome staining, the scores of Group 2 and Group 3 were determined to be significantly higher than those of the control group (p < 0.05). The Group 3 scores were significantly higher than those of Group 1 (p < 0.05). In the examinations made with fibroblast growth factor-2 staining, the scores of Group 2 and Group 3 were determined to be significantly higher than those of the control group (p < 0.05). The Group 3 scores were significantly higher than those of Group 1 and Group 2 (p < 0.05). In the examinations made with perilipin staining, the scores in Groups 1, 2, and 3 were higher than those of the control group (p < 0.05). CONCLUSION: Although metoprolol has previously been shown to prolong the survival of fat grafts, the results of this study demonstrated immunohistochemically that as the metoprolol dose increased, so the quality and vitality of fat graft also increased. 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 .

Effects of Insulin, Metoprolol and Deferoxamine on Fat Graft Survival.

BACKGROUND: The main problem faced with fat grafting is unpredictable resorption rates. Many substances have been reported to increase the survival of fat grafts. The aim of this study was to compare the effects of insulin, metoprolol and deferoxamine on fat graft survival. METHODS: Inguinal fat pads of male Sprague-Dawley rats were harvested and split into four parts as grafts. The grafts were placed in subcutaneous pockets in four quadrants on the back area of the rats. The insulin and metoprolol group fat grafts were incubated in regular insulin and metoprolol solutions, until they were placed. Deferoxamine and control group fat grafts were placed without incubation. After surgery, the control group fat grafts were injected with 10 doses of NaCl solution once every 3 days, and the deferoxamine group fat grafts were injected with 10 doses of deferoxamine solution once every 3 days. After a graft maturation period of 3 months, the grafts were harvested for weight measurements and histological and immunohistochemical evaluation. RESULTS: According to the rate of perilipin staining, the metoprolol group had 30% more mature viable adipocytes than the control and insulin group fat grafts (p < 0.05 and p < 0.01, respectively). CD31 activation rates were significantly higher in the deferoxamine and insulin group than in the metoprolol group (p < 0.05). CD34 staining rates did not differ between any groups (p > 0.05). CONCLUSIONS: In this experimental study, we have shown that there was no significantly increased fat graft survival rate seen in any drug treatment group. Low survival rates of stem cells demonstrated that the adipogenesis period ended at 3 months. Treatment of fat grafts with the selective ß1-blocker metoprolol resulted in good quality better graft take with more viable mature adipocytes. However, better viability of adipocytes did not result in increased weight of the fat graft. Studies aiming to compare the effects on fat graft survival of beta-blockers with long or short durations of action, different potencies and different receptor selectivity may be designed in the future. In addition, further studies may be performed, in which immunohistochemical markers used to assess inflammation and fibrosis are added to the study after the completion of the fat graft maturation period at the end of the first year to test the permanence of the results. NO LEVEL ASSIGNED: 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 .