Abstract
Tetramethylpyrazine (TMP), a natural active compound with known wound-healing and pro-angiogenic properties, was investigated in this study to elucidate the molecular mechanisms underlying its synergistic effects with adipose-derived stem cells (ADSCs) in skin injury repair, focusing on mitochondrial transfer. A full-thickness skin wound model in rats was established to assess therapeutic outcomes. Histological evaluation using hematoxylin-eosin and Masson staining revealed that TMP augmented the beneficial effects of ADSCs, improving skin thickness and collagen deposition in wound tissues. Transmission electron microscopy and immunofluorescence analysis demonstrated that the combined treatment restored mitochondrial ultrastructure within the wound microenvironment and enhanced mitochondrial content in endothelial cells. To further explore the underlying mechanisms, an in vitro inflammatory human umbilical vein endothelial cell (HUVEC) model was established and co-cultured with ADSCs in the presence of TMP. The results indicated that TMP treatment increased mitochondrial homeostasis and mitochondrial transfer from ADSCs to HUVECs, while enhancing expression of angiogenic factors and reducing inflammatory cytokines levels. To determine the role of connexin 43 (GJA1) in this process, lentiviral-mediated shRNA knockdown was performed in ADSCs. GJA1 deficiency abolished the pro-angiogenic effects of TMP and impaired mitochondrial transfer to HUVECs, confirming the critical role of GJA1 in mediating these processes. Collectively, these findings demonstrate that TMP enhances the therapeutic efficacy of ADSCs in wound healing by facilitating GJA1-dependent mitochondrial transfer, thereby improving endothelial cell function and promoting angiogenesis.Supplementary information
The online version contains supplementary material available at https://doi.org/10.1007/s10616-026-01078-5.