Antioxidant support in composite musculo-adipose-fasciocutaneous flap applications: an experimental study

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

BACKGROUND

Although studies aiming to increase fat graft survival continue, in this study, the authors aimed to investigate the effects of different antioxidants on total antioxidant capacity (TAC) 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 (10 mg/kg), zinc (2 mg/kg), or vitamins E and C (100 mg/kg). Autologous fat grafts (1.7 ± 0.4 g) were transferred to the dorsal subcutaneous region, and total antioxidant capacity was measured on days 0 and 1, week 1, and monthly until the third month. Transferred graft volume and mass (1.3 ± 0.4 g) were measured using the liquid overflow method and precision scales at the end of the study. Routine hematoxylin and 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). The control group exhibited a reduction in TAC, whereas all groups receiving antioxidants had an increase in TAC during the first week ( P = 0.02, P = 0.008, and P = 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.

CONCLUSION

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.

CLINICAL RELEVANCE STATEMENT

Antioxidants improve fat graft survival and quality in this rat model, by increasing total antioxidant capacity in the first week of administration.

Systematic review of pathologic markers in skin ischemia with and without reperfusion injury in microsurgical reconstruction: Biomarker alterations precede histological structure changes

BACKGROUND

Ischemia and ischemia-reperfusion injury contribute to partial or complete flap necrosis. Traditionally, skin histology has been used to evaluate morphological and structural changes, however histology does not detect early changes. We hypothesize that morphological and structural skin changes in response to ischemia and IRI occur late, and modification of gene and protein expression are the earliest changes in ischemia and IRI.

METHODS

A systematic review was performed in accordance with PRISMA guidelines. Studies reporting skin histology or gene/protein expression changes following ischemia with or without reperfusion injury published between 2002 and 2022 were included. The primary outcomes were descriptive and semi-quantitative histological structural changes, leukocyte infiltration, edema, vessel density; secondary outcomes were quantitative gene and protein expression intensity (PCR and western blot). Model type, experimental intervention, ischemia method and duration, reperfusion duration, biopsy location and time point were collected.

RESULTS

One hundred and one articles were included. Hematoxylin and eosin (H&E) showed inflammatory infiltration in early responses (12-24 h), with structural modifications (3-14 days) and neovascularization (5-14 days) as delayed responses. Immunohistochemistry (IHC) identified angiogenesis (CD31, CD34), apoptosis (TUNEL, caspase-3, Bax/Bcl-2), and protein localization (NF-κB). Gene (PCR) and protein expression (western blot) detected inflammation and apoptosis; endoplasmic reticulum stress/oxidative stress and hypoxia; and neovascularization. The most common markers were TNF-α, IL-6 and IL-1β (inflammation), caspase-3 (apoptosis), VEGF (neovascularization), and HIF-1α (hypoxia).

CONCLUSION

There is no consensus or standard for reporting skin injury during ischemia and IRI. H&E histology is most frequently performed but is primarily descriptive and lacks sensitivity for early skin injury. Immunohistochemistry and gene/protein expression reveal immediate and quantitative cellular responses to skin ischemia and IRI. Future research is needed towards a universally-accepted skin injury scoring system.

3',4'-Dihydroxyflavonol (DiOHF) prevents DNA damage, lipid peroxidation and inflammation in ovarian ischaemia-reperfusion injury of rats

This study aimed to determine the effect of 3',4'-Dihydroxyflavonol (DiOHF) on lipid peroxidation, DNA damage and inflammation in ovarian ischaemia (I)-reperfusion (R) injury. This study was performed on 44 Wistar-albino female rats. Groups were designed as Control; Sham; I/R (the left ovary was ligated for 2 h and then reperfused for 2 h); I/R + DiOHF (after 2 h ischaemia and 2 h reperfusion, 30 mg/kg of DiOHF was given intraperitoneally and reperfusion was allowed for 2 h more); I + DiOHF + R (after 2 h I, 30 mg/kg of DiOHF was given at the beginning of 2 h reperfusion); DiOHF + I/R (2 h after DiOHF administration, the left ovary was ligated for 2 h and then reperfused for 2 h). Blood and ovarian tissue samples were analysed for GSH, MDA, 8-OHdG, SOD, and IL-6. Ovarian tissue was examined histopathologically. Ovarian I/R has led to inflammation and oxidative damage. However, DiOHF activated the antioxidant system and prevented DNA damage induced by I/R in ovarian tissue. Vascularisation, oedema, and inflammation also occurred in ovarian tissue in I/R group. The results of this study indicated that I/R led to disturbance of the oxidant/antioxidant system balance and increased DNA damage; however, DiOHF supplementation prevented DNA damage, lipid peroxidation and inflammation by increasing the antioxidant system in ovarian I/R injury in rats. However, in potential I/R situations, DiOHF application appears to be beneficial in reducing inflammation, oxidant injury, and DNA damage, and in activating the antioxidant system. IMPACT STATEMENTWhat is already known on this subject? Ischaemia/reperfusion (I/R) injuries lead to damage in cells or tissues due to insufficient blood flow.What do the results of this study add? Increased DNA injury and inflammatory response (IL-6) and structural impairment were treated by administration of intraperitoneal (DiOHF) which strongly stimulated the antioxidant system, inhibited antioxidant activities, prevented DNA damage and inflammation process.What are the implications of these findings for clinical practice and/or further research? This study's strength is that it is the first research demonstrates the prevention of DNA damage in ovarian I/R by DiOHF supplementation. This flavonoid (DiOHF) may be used for treatment in different ovarian ischaemia/reperfusion.

Comparison of the efficacy of multiple antioxidant and hyperbaric oxygen treatments in the prevention of ischemia and necrosis of local random McFarlane skin flap

OBJECTIVE

The aim of this study was to compare the efficacy of multiple antioxidant (Proxeed Plus (PP) with Carnitine, Selenium, Zinc, Coenzyme Q10, Vitamin C, Folic Acid, Vitamin B12) on local random skin flap healing with the hyperbaric oxygen (HBO) therapy.

METHODS

Fourty rats were equally divided into five groups (Control, PP, HBO, HBO + PP, PP + HBO + PP). Local random McFarlane skin flap was applied to all rats. Following the applications, evaluations were made biochemical (TAS, TOS, OSI, IL-1β, IL-6, TNF-α, TGF-β, VEGF) and histopathological parameters.

RESULTS

Necrosis percentage was found to be lower in the PP + HBO + PP group than all other groups whereas the necrosis percentages of PP and HBO groups were similar. Oxidative stress rates were significantly higher in the control group compared to the other groups whereas it was lower in the PP + HBO + PP group than all other groups. The inflammation parameters were the highest in the control group and the lowest in the PP + HBO + PP group. Growth factors were higher in the PP + HBO + PP group than all other groups. Epithelialization and wound healing were better in the HBO and PP groups than in the control group. The greatest healing, epithelialization and vascularization was seen in the PP + HBO + PP group. The histopathological findings in the PP + HBO + PP group were better in each inner region than in the other groups.

CONCLUSION

Biochemical and histopathological parameters have shown that PP reduces ischemia and necrosis and increases oxygenation in flap healing by providing significant improvement thanks to the multiple molecular structures in its content.

Nutritional and Pharmacological Effects on Oxidative Stress in Soft Tissue and Bone Remodeling

Oxidative damage is the causal link to a multitude of pathologies, such as diabetes, arthritis, neuropathy, heart disease, and asthma. These conditions affect hundreds of millions of people nationwide, and billions worldwide. Even in otherwise healthy individuals, oxidative stress is a natural byproduct of metabolism that is augmented in "healthy" activities such as athletics. In many disease states, the pharmacological agents used to treat these conditions can induce oxidative damage and vitamin depletion. It is underappreciated by many that many of the most common medications prescribed result in oxidative stress. Therefore, physicians need to carefully scrutinize which medications their patients are on before surgery and treatment and during the recovery stage to obtain optimal healing results. We provide a review of the current literature of how oxidative damage and inflammation are linked to bone damage, Charcot neuroarthropathy, delayed wound healing, diabetic complications, and delayed flap consolidation. Where available, antioxidant intervention literature is offered to offset these conditions.

Effects of ozone gas on skin flaps viability in rats: an experimental study

BACKGROUND

The main purpose of this study was to assess the effects of ozone gas on the viability of flaps for reconstruction and to determine the optimum application method. The antioxidant, immunomodulatory, and reperfusion effects of ozone gas have been previously assessed, and successful results have been reported. However, only one study has investigated the effect of ozone gas on flap viability. In the present study, it was hypothesised that the antioxidant and reperfusion effects of ozone gas would enhance flap viability.

METHODS

Forty female Wistar rats were randomly divided into four groups of 10 rats each. A cranial-based, 3 × 11 cm modified McFarlane flap including the panniculus carnosus was raised from the dorsum of a rat and re-sutured to its own bed using 3/0 sharp propylene. Group 1 (n = 10): no pharmacological agent was used after the operation. Group 2 (n = 10): vegetable (olive) oil group; vegetable-oil-impregnated gauze was used as a dressing for 7 days. Group 3 (n = 10): Vegetable (olive) oil with ozone peroxide group; vegetable oil with ozone peroxide-impregnated gauze was used as a dressing for 7 days. Group 4 (n = 10): Hemo-ozone therapy group; hemo-ozone therapy was applied rectally once every day for 7 days. All rats were sacrificed at the end of week 1 and assessed macroscopically and histopathologically.

RESULTS

The proportion of substantive necrosis was less in group 4 than in the other three groups. Survival area ratios were better in groups 2 and 3 than in group 1; however, there was no significant difference between groups 2 and 3. No significant differences in the histopathological scores were observed among the groups.

CONCLUSION

Ozone gas enhanced flap viability. No differences in flap viability were observed between the vegetable oil and vegetable oil with ozone peroxide groups. The greatest benefit ratios were found in the hemo-ozone therapy group.

Grape seed proanthocyanidin protects liver against ischemia/reperfusion injury by attenuating endoplasmic reticulum stress

AIM: To explore the effect of grape seed proanthocyanidin (GSP) in liver ischemia/reperfusion (IR) injury and alleviation of endoplasmic reticulum stress.

METHODS: Male Sprague-Dawley rats (220-250 g) were divided into three groups, namely, sham, IR, and GSP groups (n = 8 each). A liver IR (70%) model was established and reperfused for 6 h. Prior to reperfusion, the GSP group was administered with GSP (100 mg/kg) for 15 d, and liver histology was then investigated. Serum aminotransferase and inflammatory mediators coupled with superoxide dismutase and methane dicarboxylic aldehyde were detected. Western blot was conducted to analyze the expression of glucose-regulated protein 78, CCAAT/enhancer-binding protein homologous protein, activating transcription factor-4, inositol-requiring enzyme-1, procaspase-12, and nuclear factor-κb. Apoptotic cells were detected by TUNEL staining.

RESULTS: The serum aminotransferase, apoptotic cells, and Suzuki scores decreased in the GSP group compared with the IR group (Ps < 0.05). The methane dicarboxylic aldehyde level was decreased in the GSP group, but the superoxide dismutase level was reversed (Ps < 0.05). Similarly, GSP downregulated the proinflammatory factors and upregulated the levels of anti-inflammatory factors (Ps < 0.05). Western blot data showed that GSP increased glucose-regulated protein 78 expression and suppressed expression of CCAAT/enhancer-binding protein homologous protein, activating transcription factor-4, inositol-requiring enzyme-1, procaspase-12, and nuclear factor-κb compared with the IR group.

CONCLUSION: GSP possesses antioxidative, anti-inflammatory, and antiapoptotic effects by relieving endoplasmic reticulum stress through regulation of related signaling pathways to protect the liver against IR injury.