Bone microenvironment regulative hydrogels with ROS scavenging and prolonged oxygen-generating for enhancing bone repair

Han Sun; Juan Xu; Yangyufan Wang; Siyu Shen; Xingquan Xu; Lei Zhang; Qing Jiang

doi:10.1016/j.bioactmat.2022.12.021

Bone microenvironment regulative hydrogels with ROS scavenging and prolonged oxygen-generating for enhancing bone repair

Bioact Mater. 2023 Jan 9:24:477-496. doi: 10.1016/j.bioactmat.2022.12.021. eCollection 2023 Jun.

Authors

Han Sun^{1

2

3

4}, Juan Xu^{1

2

3}, Yangyufan Wang^{1

2

3}, Siyu Shen^{1

2

3}, Xingquan Xu^{1

2

3}, Lei Zhang^{1

2

3}, Qing Jiang^{1

2

3}

Affiliations

¹ State Key Laboratory of Pharmaceutical Biotechnology, Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China.
² Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, PR China.
³ Co-innovation Center of Neuroregeneration, Nantong University, 9 Seyuan Road, Nantong, 226019, Jiangsu, PR China.
⁴ Articular Orthopaedics, The Third Affiliated Hospital of Soochow University, 185 Juqian Road, Changzhou, 213003, Jiangsu, PR China.

Abstract

Large bone defects resulting from fractures and disease are a major clinical challenge, being often unable to heal spontaneously by the body's repair mechanisms. Lines of evidence have shown that hypoxia-induced overproduction of ROS in bone defect region has a major impact on delaying bone regeneration. However, replenishing excess oxygen in a short time cause high oxygen tension that affect the activity of osteoblast precursor cells. Therefore, reasonably restoring the hypoxic condition of bone microenvironment is essential for facilitating bone repair. Herein, we designed ROS scavenging and responsive prolonged oxygen-generating hydrogels (CPP-L/GelMA) as a "bone microenvironment regulative hydrogel" to reverse the hypoxic microenvironment in bone defects region. CPP-L/GelMA hydrogels comprises an antioxidant enzyme catalase (CAT) and ROS-responsive oxygen-releasing nanoparticles (PFC@PLGA/PPS) co-loaded liposome (CCP-L) and GelMA hydrogels. Under hypoxic condition, CPP-L/GelMA can release CAT for degrading hydrogen peroxide to generate oxygen and be triggered by superfluous ROS to continuously release the oxygen for more than 2 weeks. The prolonged oxygen enriched microenvironment generated by CPP-L/GelMA hydrogel significantly enhanced angiogenesis and osteogenesis while inhibited osteoclastogenesis. Finally, CPP-L/GelMA showed excellent bone regeneration effect in a mice skull defect model through the Nrf2-BMAL1-autophagy pathway. Hence, CPP-L/GelMA, as a bone microenvironment regulative hydrogel for bone tissue respiration, can effectively scavenge ROS and provide prolonged oxygen supply according to the demand in bone defect region, possessing of great clinical therapeutic potential.

Keywords: Alizarin red staining, ARS; Alkaline phosphatase, ALP; Bone defect; Bone marrow mesenchymal stem cells, BMSC; Bovine serum albumin, BSA; Brain and muscle arnt-like protein 1; Brain and muscle arnt-like protein 1, BMAL1; Catalase, CAT; Fetal liver kinase-1, Flk-1; Human umbilical vein endothelial cells, HUVEC; Hypoxic microenvironment; Liposome, Lip; Microtubule-associated proteins light chain 3, LC3; Nuclear factor (erythroid-derived 2)-like 2, NRF2; Osteocalcin, OCN; Osteopontin, OPN; Perfluorocarbon, PFC; Phosphate-buffered saline, PBS; Poly (D, L-lactide-co-glycolide), PLGA; Poly (propylene sulphide), PPS; Prolonged oxygen generation; Reactive oxygen species responsiveness; Reactive oxygen species, ROS; Receptor activator of nuclear factor-kappa B ligand, RANKL; Runt-related transcription factor 2, RUNX2; Short interfering RNA, siRNA; Soy phosphatidylcholine, SPC; Type I collagen, Col I; Western blot, WB.