Prediction of the Postoperative Fat Volume Retention Rate After Augmentation Mammoplasty with Autologous Fat Grafting: From the Perspective of Preoperative Inflammatory Level

Pyrroloquinoline Quinone (PQQ) Improves Long-term Survival of Fat Grafts by Alleviating Oxidative Stress and Promoting Angiogenesis During the Early Phase After Transplantation

BACKGROUND

Reducing absorption after autologous fat grafting is a current challenge. Pyrroloquinoline quinone (PQQ) is the strongest known catalyst of redox reactions, which can scavenge reactive oxygen species (ROS) and alleviate oxidative stress.

OBJECTIVES

The aim of this study was to establish an in vivo model of PQQ-assisted lipotransfer and clarify the role of PQQ in reducing oxidative stress, alleviating apoptosis, and promoting angiogenesis during the acute hypoxic phase after grafting. In addition the study was performed to assess whether this intervention would have a positive effect on the improvement of long-term volume retention.

METHODS

Different concentrations of PQQ (low: 10 μM, medium: 100 μM, and high: 1000 μM) were mixed with human adipose tissue and transplanted subcutaneously into nude mice. Meanwhile, a control group of phosphate-buffered saline in an equal volume to PQQ was set up. On the third day after grafting, whole mount fluorescence staining was applied to detect ROS, mitochondrial membrane potential (MMP), apoptosis, adipocyte activity, and angiogenesis. Graft volume retention rate and electron microscopic morphology were evaluated at the third month. Immunohistochemistry and polymerase chain reaction (PCR) were further employed to elucidate the mechanism of action of PQQ.

RESULTS

PQQ-assisted fat grafting improved the long-term volume retention, promoted the quality and viability of the adipose tissue, and reduced the level of fibrosis. The underlying mechanism of PQQ assisted in scavenging the accumulated ROS, restoring MMP, enhancing adipocyte viability, alleviating tissue apoptosis, and promoting timely angiogenesis during the hypoxia stress phase. The most effective concentration of PQQ was 100 μM. Immunohistochemistry and PCR experiments confirmed that PQQ reduced the expression of Bax and cytochrome c in the mitochondrial apoptotic pathway and increased the level of the antiapoptotic molecule Bcl-2.

CONCLUSIONS

PQQ could improve the long-term survival of adipocytes by alleviating hypoxic stress and promoting timely angiogenesis in the early phase following lipotransfer.

LEVEL OF EVIDENCE: 4

Prediction of the Postoperative Bone Regeneration Rate After Mandibular Reduction: From the Perspective of Preoperative Inflammatory and Immune Status

BACKGROUND

Following mandibular reduction, bone regeneration in the angle region is a problem that can affect facial aesthetics and lead to revision surgery. The bone regeneration rate (BRR) varies between individuals and is difficult to predict. However, studies focusing on preoperative patient-related factors are lacking. As bone regeneration is closely related to the inflammatory and immune status of the organism, according to in vitro and in vivo evidence, preoperative inflammatory indicators were included in this study as potential predictors.

METHODS

Demographic and preoperative laboratory data were included as independent variables. The BRR calculated from computed tomography data was included as the dependent variable. Univariate analysis and multiple linear regression analysis were used to determine the key factors influencing the BRR. The ROC curves were used to analyse the corresponding predictive efficacy.

RESULTS

23 patients (46 mandibular angles) fulfilled the inclusion criteria. The mean bilateral BRR was 23.82 ± 9.90%. Preoperative monocyte count (M) was an independent positive factor for BRR, and age was a negative factor. Only M had a good predictive ability, and its optimal cut-off point to distinguish patients with BRR greater than 30% was 0.305 × 109/L. Other parameters were not significantly correlated with BRR.

CONCLUSIONS

Patient age and preoperative M may influence BRR, with M having a positive effect and age having a negative effect. According to the preoperative blood routine tests that are readily available, using the diagnostic threshold (M [Formula: see text] 0.305 × 109/L) derived from this study, surgeons can better predict BRR and identify patients whose BRR is greater than the mean level.

LEVEL OF EVIDENCE IV

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