Hypoxia-preconditioned adipose-derived stem cells combined with scaffold promote urethral reconstruction by upregulation of angiogenesis and glycolysis

Abstract

Rationale Tissue engineering is a promising alternative for urethral reconstruction, and adipose-derived stem cells (ADSCs) are widely used as seeding cells. Hypoxia preconditioning can significantly enhance the therapeutic effects of ADSCs. The low oxygen tension of postoperative wound healing is inevitable and may facilitate the nutritional function of ADSCs. This study aimed to investigate if hypoxia-preconditioned ADSCs, compared to normoxia-preconditioned ADSCs, combined with scaffold could better promote urethral reconstruction and exploring the underlying mechanism. Methods In vitro, paracrine cytokines and secretomes that were secreted by hypoxia- or normoxia-preconditioned ADSCs were added to cultures of human umbilical vein endothelial cells (HUVECs) to measure their functions. In vivo, hypoxia- or normoxia-preconditioned ADSCs were seeded on a porous nanofibrous scaffold for urethral repair on a defect model in rabbits. Results The in vitro results showed that hypoxia could enhance the secretion of VEGFA by ADSCs, and hypoxia-preconditioned ADSCs could enhance the viability, proliferation, migration, angiogenesis, and glycolysis of HUVECs (p < 0.05). After silencing VEGFA, angiogenesis and glycolysis were significantly inhibited (p < 0.05). The in vivo results showed that compared to normoxia-preconditioned ADSCs, hypoxia-preconditioned ADSCs combined with scaffolds led to a larger urethral lumen diameter, preserved urethral morphology, and enhanced angiogenesis (p < 0.05). Conclusions Hypoxia preconditioning of ADSCs combined with scaffold could better promote urethral reconstruction by upregulating angiogenesis and glycolysis. Hypoxia-preconditioned ADSCs combined with novel scaffold may provide a promising alternative treatment for urethral reconstruction.

Hypoxic preconditioning rejuvenates mesenchymal stem cells and enhances neuroprotection following intracerebral hemorrhage via the miR-326-mediated autophagy

“…Although naïve MSCs are still the most common approach used to treat ICH, researches are being conducted to discover several methods to culture more functional MSCs, including pharmacologic pre-conditioning [ 54 ], alternative cell delivery approaches [ 55 – 57 ], genetic modification [ 58 , 59 ], physical methods [ 60 ], and modification of culture conditions [ 14 , 17 ]. Hypoxic preconditioning is a modification of culture conditions that have been shown to improve the therapeutic efficacy of stem cells in a model of atherosclerotic renal artery stenosis [ 61 ], spinal cord injury [ 62 ], ischemic stroke [ 18 , 63 , 64 ], acute lung injury [ 65 ], myocardial infarction [ 15 ], chronic liver injury [ 66 ], urethral injury [ 67 ], and ICH [ 14 , 17 ]. The oxygen concentrations evaluated in most of these studies include 0.1–0.3% O 2 , 1% O 2 , 3% O 2 , and 5% O 2 , and the treatment durations range from 24 to 48 h. In a general setting, MSCs are cultured under normoxia niche (~21%) [ 68 ].…”

Application of antibody-conjugated small intestine submucosa to capture urine-derived stem cells for bladder repair in a rabbit model

“…To seed the USCs onto the SIS for the repair of tissue defects has achieved satisfactory outcome and better efficacy compared with transplantation of the USCs or SIS alone [ 10 , 12 , 70 , 71 ]. However, due to the pH value and flowing environment, to directly seed the USCs onto the SIS membrane may result in rapid cell death and reduced therapeutic effect.…”

“…Advances in tissue engineering and regenerative medicine have enabled scientists to develop more promising and revolutionary treatment strategies for bladder regeneration [ 8 ]. Ongoing strategies for the regeneration of defective and/or lost tissues have based on construction of biological scaffolds by using pliable scaffolds which can mimic the active and passive bi-axial mechanical properties of the organ in combination with stem cells for tissue regeneration [ [9] , [10] , [11] , [12] ]. Direct seeding stem cells onto the scaffolds to fabricate a patch for bladder repair has become a commonly used strategy [ [13] , [14] , [15] , [16] ].…”

Human iPSC-Derived Vascular Smooth Muscle Cells in a Fibronectin Functionalized Collagen Hydrogel Augment Endothelial Cell Morphogenesis

“…The conditioned medium (CM) from the hydrogels was characterized for paracrine factors using ELISA and following a standard method [ 17 , 28 , 37 , 38 , 39 , 40 ]. Day 3 and 7 CM collected from the culture were used to perform ELISA to assess for proangiogenic growth factors vascular endothelial growth factor (VEGF) and bFGF, as previously described [ 17 , 28 ].…”