Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian resto...Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian restoration.In this study,a subcutaneous implantation system using gelatin methacryloyl(GelMA)hydrogel embedded with ICA was developed to restore ovarian function in aged female mice.Mice were assigned to receive subcutaneous implantation of GelMA alone(GelMA group),GelMA containing ICA(GelMA/ICA group),or a sham operation.Ovarian morphology,serum hormone levels,follicle counts across developmental stages,and reproductive outcomes were evaluated.In vitro fertilization(IVF)and embryo culture assays were performed to assess oocyte developmental potential,while a 10 day natural mating trial was conducted to determine fertility restoration.RNA sequencing(RNA-seq)and RT-qPCR were performed to elucidate the underlying molecular mechanisms.Results showed that GelMA/ICA treatment significantly increased ovarian index(0.19±0.01 vs.0.13±0.01,P<0.0001)and follicle numbers at all developmental stages,including primordial(383.33±151.65 vs.107.14±32.26,P<0.0001),primary(203.33±83.22 vs.91.43±27.04,P=0.003),and secondary follicles(154.17±52.00 vs.59.28±20.50,P=0.029)compared to the sham controls.Hormonal analyses revealed a significant reduction in serum follicle-stimulating hormone(FSH,11.97±3.53 vs.53.10±17.89 ng/mL,P=0.0008),accompanied by elevated anti-Müllerian hormone(AMH,22.97±2.26 vs.5.54±1.56 ng/mL,P<0.0001)and estradiol(E2,315.30±37.62 vs.168.5±14.78 pg/mL,P<0.0001).Oocyte yield and developmental potential improved significantly,as reflected by the increased number of superovulated MII oocytes(17.83±5.15 vs.4.83±4.79,P=0.0002),and higher proportions of two-cell(85.90%±6.16%vs.50.00%±10.00%,P=0.0009),four-cell(81.67%±9.76%vs.50.00%±10.00%,P=0.0061),and blastocyst stage embryos(64.25%±10.55%vs.23.33%±15.28%,P=0.0067).Live birth numbers were significantly increased following GelMA/ICA treatment(6.90±3.21 vs.1.72±2.05,P=0.0001).Transcriptomic analysis revealed up-regulation of genes associated with cytoskeletal organization(Vil1,Tubb3),lipid storage(Soat2,Plin4),oocyte maturation(Oosp2),and cytokine secretion(Cxcl12).Collectively,these findings suggest that GelMA/ICA hydrogels effectively reverse key hallmarks of ovarian aging and restore reproductive function in aged mice,offering a promising platform for fertility preservation and a novel therapeutic for future investigations into ovarian aging.展开更多
The three-dimensional (3D)bioprinting technology has progressed tremendously over the past decade.By controlling the size, shape,and architecture of the bioprinted constructs,3D bioprinting allows for the fabrication ...The three-dimensional (3D)bioprinting technology has progressed tremendously over the past decade.By controlling the size, shape,and architecture of the bioprinted constructs,3D bioprinting allows for the fabrication of tissue/organ-like constructs with strong structural-functional similarity with their in vivo counterparts at high fidelity.The bioink,a blend of biomaterials and living cells possessing both high biocompatibility and printability,is a critical component of bioprinting.In particular, gelatin methacryloyl (GelMA)has shown its potential as a viable bioink material due to its suitable biocompatibility and readily tunable physicochemical properties.Current GelMA-based bioinks and relevant bioprinting strategies for GelMA bioprinting are briefly reviewed.展开更多
Dear Editor,Three dimensional(3D)bioprinted extracellular matrix(ECM)can be used to provide both biochemical and biophysical cues to direct mesenchymal stem cells(MSCs)differentiation,and then differentiated cells wer...Dear Editor,Three dimensional(3D)bioprinted extracellular matrix(ECM)can be used to provide both biochemical and biophysical cues to direct mesenchymal stem cells(MSCs)differentiation,and then differentiated cells were isolated for implantation in vivo using surgical procedures.However,the reduced cell activity after cell isolation from 3D constructs and low cell retention in injured sites limit its application[1].Methacrylated gelatin(GelMA)hydrogel has the advantage of fast crosslinking,which could resemble complex architectures of tissue construct in vivo[2].Here,we adopted a noninvasive bioprinting procedure to imitate the regenerative microenvironment that could simultaneously direct the sweat gland(SG)and vascular differentiation from MSCs and ultimately promote the replacement of glandular tissue in situ(Fig.1a).展开更多
Methacrylated gelatin(GelMA)hydrogels have been well-recognized as a widely-used natural polymer for biofabrications due to the adaptability for multiple crosslinking schemes,desirable biocompatibility and biodegradab...Methacrylated gelatin(GelMA)hydrogels have been well-recognized as a widely-used natural polymer for biofabrications due to the adaptability for multiple crosslinking schemes,desirable biocompatibility and biodegradability,and ease of chemical functionalization.With regard to 3D bioprinting,however,GelMA has shown unsatisfactory printing stability and accuracy due to slow sol-gel transition,suboptimal mechanical strength,and strict temperature control for printing.We herein developed an innovative dual-crosslinkable colloidal inks composed of self-assembled GelMA nanospheres with 80%self-healing efficiency,which outperform the traditional GelMA polymeric inks in terms of enhanced printability and fidelity,broader printing temperature range,adjustable mechanical strength ranging from brain analogue 2.83 kPa to cardiac analogue 52.45 kPa,and improved bio-functionalities evidenced by the elevated hydrophilicity,mass transfer efficiency and prolonged drug release profile.Moreover,the granulation design of GelMA inks unlocked freeform 3D printing modes such as direct multi-ink writing,embedded printing,but also allowed in-situ printing directly at the bleeding wound sites due to the outstanding hemostatic efficacy and network stability of colloidal gels.In general,our nanostructured GelMA colloidal inks present a better replacement for the traditional GelMA polymeric inks in 3D bioprinting,which establishes a foundation for bench-to-bedside translations of 3D printing techniques towards more practical clinical applications.展开更多
Burn wound healing is a multifaceted process often complicated by excessive inflammation and impaired ker-atinocyte function,both of which are key factors contributing to delayed healing.In this study we screened the ...Burn wound healing is a multifaceted process often complicated by excessive inflammation and impaired ker-atinocyte function,both of which are key factors contributing to delayed healing.In this study we screened the key miRNA regulating the epithelialization process under oxidative stress conditions through high-throughput sequencing.We identified that miR-192-5p was significantly upregulated in both oxidative stress models of keratinocytes and burn wound tissues,with detrimental effects on keratinocyte proliferation,migration,and apoptosis.Inhibition of miR-192-5p enhanced epidermal cell function by upregulating olfactomedin-4(OLFM4),a key gene associated with cell proliferation,adhesion and migration.To optimize delivery and therapeutic efficacy,we engineered MSC-derived exosomes loaded with antagomiR-192-5p(ant-192;Final content:2 nmol per wound;Loading efficiency:35.22±0.34%)and then encapsulated into a composite hydrogel composed of GelMA and MXene(Ti3C2Tx)nanosheets,forming a multifunctional dressing(Exo-ant-192@M-Gel).It achieved sustained release of ant-192,delay its degradation,and exert anti-inflammatory properties,thus promoting epithelization and burn wound healing.This study offered a novel therapeutic approach for burn wound closure.展开更多
Spinal cord injury(SCI)is a severe neurological condition with limited regenerative capacity and no effective curative treatments.Interleukin-13(IL-13),an immunomodulatory cytokine,has shown therapeutic potential by p...Spinal cord injury(SCI)is a severe neurological condition with limited regenerative capacity and no effective curative treatments.Interleukin-13(IL-13),an immunomodulatory cytokine,has shown therapeutic potential by promoting alternative immune activation and improving recovery after SCI in mice.However,cellbased IL-13 delivery is hindered by poor graft survival and limited localisation at the injury site.Here,we developed an injectable hydrogel-based delivery system(HGIL13)composed of IL-13-loaded poly(lactic-co-glycolic acid)(PLGA)microparticles embedded in a photocrosslinkable gelatin methacrylate(GelMA)matrix,enabling sustained and localised IL-13 release.HGIL13 achieved IL-13 release for up to six weeks and significantly reduced lipopolysaccharide(LPS)-induced inflammation in BV2 microglia in vitro.In a mouse contusion SCI model,HGIL13 enhanced functional recovery,reduced lesion volume,and decreased demyelinated area.Using the Hexbtd^(Tomato)mouse we show that HGIL13 modulated the neuroimmune response by decreasing resident microglia density,downregulating CD86 expression,and upregulating Arginase-1 in both microglia and infiltrating monocyte-derived macrophages.RT-qPCR and RNA-seq analyses confirmed sustained immunomodulation over 28 days and indicated early reduction of activated microglia at 7 days post-injury as a key therapeutic mechanism.This study presents a safe,effective,and translatable strategy for localised cytokine delivery,demonstrating strong potential for immunomodulation and improved functional recovery following SCI.展开更多
Polymeric hydrogels are fascinating platforms as 3D scaffolds for tissue repair and delivery systems of therapeutic molecules and cells.Among others,methacrylated gelatin(GelMA)has become a representative hydrogel for...Polymeric hydrogels are fascinating platforms as 3D scaffolds for tissue repair and delivery systems of therapeutic molecules and cells.Among others,methacrylated gelatin(GelMA)has become a representative hydrogel formulation,finding various biomedical applications.Recent efforts on GelMA-based hydrogels have been devoted to combining them with bioactive and functional nanomaterials,aiming to provide enhanced physicochemical and biological properties to GelMA.The benefits of this approach are multiple:i)reinforcing mechanical properties,ii)modulating viscoelastic property to allow 3D printability of bio-inks,iii)rendering electrical/magnetic property to produce electro-/magneto-active hydrogels for the repair of specific tissues(e.g.,muscle,nerve),iv)providing stimuli-responsiveness to actively deliver therapeutic molecules,and v)endowing therapeutic capacity in tissue repair process(e.g.,antioxidant effects).The nanomaterial-combined GelMA systems have shown significantly enhanced and extraordinary behaviors in various tissues(bone,skin,cardiac,and nerve)that are rarely observable with GelMA.Here we systematically review these recent efforts in nanomaterials-combined GelMA hydrogels that are considered as next-generation multifunctional platforms for tissue therapeutics.The approaches used in GelMA can also apply to other existing polymeric hydrogel systems.展开更多
The dynamic extracellular matrix(ECM)constantly affects the behaviors of cells.To mimic the dynamics of ECM with controllable stiffness and energy dissipation,this study proposes a strategy in which a small molecule,3...The dynamic extracellular matrix(ECM)constantly affects the behaviors of cells.To mimic the dynamics of ECM with controllable stiffness and energy dissipation,this study proposes a strategy in which a small molecule,3,4-dihydroxybenzaldehyde(DB),was used as fast"dynamic bridges"to construct viscoelastic gelatin methacryloyl(GelMA)-based hydrogels.The storage modulus and loss modulus of hydrogels were independently adjusted by the covalent crosslinking density and by the number of dynamic bonds.The hydrogels exhibited self-healing property,injectability,excellent adhesion and mechanical properties.Moreover,the in vitro results revealed that the viscous dissipation of hydrogels favored the spreading,proliferation,osteogenesis and chondrogenesis of bone marrow mesenchymal stem cells(BMSCs),but suppressed their adipogenesis.RNA-sequencing and immunofluorescence suggested that the viscous dissipation of hydrogels activated Yes-associated protein(YAP)by stabilizing integrinβ1,and further promoted nuclear translocation of smad2/3 andβ-catenin to enhance chondrogenesis and osteogenesis.As a result,the viscoelastic GelMA hydrogels with highest loss modulus showed best effect in cartilage and subchondral bone repair.Taken together,findings from this study reveal an effective strategy to fabricate viscoelastic hydrogels for modulating the interactions between cells and dynamic ECM to promote tissue regeneration.展开更多
Volumetric muscle loss(VML)is associated with a severe loss of muscle tissue that overwhelms the regenerative potential of skeletal muscles.Tissue engineering has shown promise for the treatment of VML injuries,as evi...Volumetric muscle loss(VML)is associated with a severe loss of muscle tissue that overwhelms the regenerative potential of skeletal muscles.Tissue engineering has shown promise for the treatment of VML injuries,as evidenced by various preclinical trials.The present study describes the fabrication of a cell-laden GelMa muscle construct using an in situ crosslinking(ISC)strategy to improve muscle functionality.To obtain optimal biophysical properties of the muscle construct,two UV exposure sources,UV exposure dose,and wall shear stress were evaluated using C2C12 myoblasts.Additionally,the ISC system showed a significantly higher degree of uniaxial alignment and myogenesis compared to the conventional crosslinking strategy(post-crosslinking).To evaluate the in vivo regenerative potential,muscle constructs laden with human adipose stem cells were used.The VML defect group implanted with the bio-printed muscle construct showed significant restoration of functionality and muscular volume.The data presented in this study suggest that stem cell-based therapies combined with the modified bioprinting process could potentially be effective against VML injuries.展开更多
基金supported by the National Natural Science Foundation of China(82271671)Nanjing Drum Tower Hospital Academic Innovation Peak Fund(2024-DF-02)+4 种基金Clinical Trials from Nanjing Drum Tower Hospital(2023-LCYJ-MS-05)Nanjing International Science and Technology Cooperation Program(202201027)to L.D.Research Project of State Key Laboratory of Reproductive Medicine and Offspring Health(SKLRM-2022D2)Changzhou Medical Center of Nanjing Medical University(CMCM202203)Clinical Trials from Nanjing Drum Tower Hospital(2022-LCYJ-ZD-02)to H.S.
文摘Ovarian aging is characterized by a progressive decline in oocyte quality and quantity with age.Icariin(ICA),a flavonoid compound derived from Epimedium species,has demonstrated potential as an agent for ovarian restoration.In this study,a subcutaneous implantation system using gelatin methacryloyl(GelMA)hydrogel embedded with ICA was developed to restore ovarian function in aged female mice.Mice were assigned to receive subcutaneous implantation of GelMA alone(GelMA group),GelMA containing ICA(GelMA/ICA group),or a sham operation.Ovarian morphology,serum hormone levels,follicle counts across developmental stages,and reproductive outcomes were evaluated.In vitro fertilization(IVF)and embryo culture assays were performed to assess oocyte developmental potential,while a 10 day natural mating trial was conducted to determine fertility restoration.RNA sequencing(RNA-seq)and RT-qPCR were performed to elucidate the underlying molecular mechanisms.Results showed that GelMA/ICA treatment significantly increased ovarian index(0.19±0.01 vs.0.13±0.01,P<0.0001)and follicle numbers at all developmental stages,including primordial(383.33±151.65 vs.107.14±32.26,P<0.0001),primary(203.33±83.22 vs.91.43±27.04,P=0.003),and secondary follicles(154.17±52.00 vs.59.28±20.50,P=0.029)compared to the sham controls.Hormonal analyses revealed a significant reduction in serum follicle-stimulating hormone(FSH,11.97±3.53 vs.53.10±17.89 ng/mL,P=0.0008),accompanied by elevated anti-Müllerian hormone(AMH,22.97±2.26 vs.5.54±1.56 ng/mL,P<0.0001)and estradiol(E2,315.30±37.62 vs.168.5±14.78 pg/mL,P<0.0001).Oocyte yield and developmental potential improved significantly,as reflected by the increased number of superovulated MII oocytes(17.83±5.15 vs.4.83±4.79,P=0.0002),and higher proportions of two-cell(85.90%±6.16%vs.50.00%±10.00%,P=0.0009),four-cell(81.67%±9.76%vs.50.00%±10.00%,P=0.0061),and blastocyst stage embryos(64.25%±10.55%vs.23.33%±15.28%,P=0.0067).Live birth numbers were significantly increased following GelMA/ICA treatment(6.90±3.21 vs.1.72±2.05,P=0.0001).Transcriptomic analysis revealed up-regulation of genes associated with cytoskeletal organization(Vil1,Tubb3),lipid storage(Soat2,Plin4),oocyte maturation(Oosp2),and cytokine secretion(Cxcl12).Collectively,these findings suggest that GelMA/ICA hydrogels effectively reverse key hallmarks of ovarian aging and restore reproductive function in aged mice,offering a promising platform for fertility preservation and a novel therapeutic for future investigations into ovarian aging.
基金the National Institutes of Health (K99CA201603,R21EB025270, R21EB026175)Doctoral New Investigator Grant from American Chemical Society Petroleum Research Fund (56840-DNI7).G.L. Y.acknowledges Natural and Science Foundation of Hubei Province (2014CFB778).
文摘The three-dimensional (3D)bioprinting technology has progressed tremendously over the past decade.By controlling the size, shape,and architecture of the bioprinted constructs,3D bioprinting allows for the fabrication of tissue/organ-like constructs with strong structural-functional similarity with their in vivo counterparts at high fidelity.The bioink,a blend of biomaterials and living cells possessing both high biocompatibility and printability,is a critical component of bioprinting.In particular, gelatin methacryloyl (GelMA)has shown its potential as a viable bioink material due to its suitable biocompatibility and readily tunable physicochemical properties.Current GelMA-based bioinks and relevant bioprinting strategies for GelMA bioprinting are briefly reviewed.
基金supported by the Science Fund for National Defense Distinguished Young Scholars(2022-JCJQ-ZQ-016)the Key Basic Research Projects of the Foundation Strengthening Plan(2022-JCJQZD-096-00)+2 种基金the National Key Research and Development Program of China(2022YFA1104604)the National Natural Science Foundation of China(32000969)the Key Support Program for Growth Factor Research(SZYZ-TR-03).
文摘Dear Editor,Three dimensional(3D)bioprinted extracellular matrix(ECM)can be used to provide both biochemical and biophysical cues to direct mesenchymal stem cells(MSCs)differentiation,and then differentiated cells were isolated for implantation in vivo using surgical procedures.However,the reduced cell activity after cell isolation from 3D constructs and low cell retention in injured sites limit its application[1].Methacrylated gelatin(GelMA)hydrogel has the advantage of fast crosslinking,which could resemble complex architectures of tissue construct in vivo[2].Here,we adopted a noninvasive bioprinting procedure to imitate the regenerative microenvironment that could simultaneously direct the sweat gland(SG)and vascular differentiation from MSCs and ultimately promote the replacement of glandular tissue in situ(Fig.1a).
基金supported by the National Key Research and Development Program of China(No.2018YFA0703000)National Natural Science Foundation of China(No.52273102,No.52302344).
文摘Methacrylated gelatin(GelMA)hydrogels have been well-recognized as a widely-used natural polymer for biofabrications due to the adaptability for multiple crosslinking schemes,desirable biocompatibility and biodegradability,and ease of chemical functionalization.With regard to 3D bioprinting,however,GelMA has shown unsatisfactory printing stability and accuracy due to slow sol-gel transition,suboptimal mechanical strength,and strict temperature control for printing.We herein developed an innovative dual-crosslinkable colloidal inks composed of self-assembled GelMA nanospheres with 80%self-healing efficiency,which outperform the traditional GelMA polymeric inks in terms of enhanced printability and fidelity,broader printing temperature range,adjustable mechanical strength ranging from brain analogue 2.83 kPa to cardiac analogue 52.45 kPa,and improved bio-functionalities evidenced by the elevated hydrophilicity,mass transfer efficiency and prolonged drug release profile.Moreover,the granulation design of GelMA inks unlocked freeform 3D printing modes such as direct multi-ink writing,embedded printing,but also allowed in-situ printing directly at the bleeding wound sites due to the outstanding hemostatic efficacy and network stability of colloidal gels.In general,our nanostructured GelMA colloidal inks present a better replacement for the traditional GelMA polymeric inks in 3D bioprinting,which establishes a foundation for bench-to-bedside translations of 3D printing techniques towards more practical clinical applications.
基金supported by the National Key R&D Program of China(2024YFA1108401)the National Nature Science Foundation of China(81930057)+7 种基金Shanghai Rising Star Program(22QA1411700,24YF2758700)CAMS Innovation Fund for Medical Sciences(2019-I2M-5-076)the National Nature Science Foundation of China(82372512,82372513,82072170 and 81772076)Shanghai Top Pri-ority Research Center Project(2023ZZ02013)Basic medical research project of Changhai Hospital(2023YQ02)Changhong talent plan of Changhai HospitalDeep Blue Talent Project of Naval Medical Univer-sityClinical Medical Research of Changhai Hospital(2024LYC06).
文摘Burn wound healing is a multifaceted process often complicated by excessive inflammation and impaired ker-atinocyte function,both of which are key factors contributing to delayed healing.In this study we screened the key miRNA regulating the epithelialization process under oxidative stress conditions through high-throughput sequencing.We identified that miR-192-5p was significantly upregulated in both oxidative stress models of keratinocytes and burn wound tissues,with detrimental effects on keratinocyte proliferation,migration,and apoptosis.Inhibition of miR-192-5p enhanced epidermal cell function by upregulating olfactomedin-4(OLFM4),a key gene associated with cell proliferation,adhesion and migration.To optimize delivery and therapeutic efficacy,we engineered MSC-derived exosomes loaded with antagomiR-192-5p(ant-192;Final content:2 nmol per wound;Loading efficiency:35.22±0.34%)and then encapsulated into a composite hydrogel composed of GelMA and MXene(Ti3C2Tx)nanosheets,forming a multifunctional dressing(Exo-ant-192@M-Gel).It achieved sustained release of ant-192,delay its degradation,and exert anti-inflammatory properties,thus promoting epithelization and burn wound healing.This study offered a novel therapeutic approach for burn wound closure.
基金supported by University College Dublin and Taighde ireann-Research Ireland(19/FFP/6642 to DD,16/IA/4584 to DB,and GOIPG/2021/304 to CW)supported by the Medical Research Center Initiative for High Depth Omics,and CURE:JPMXP1323015486 for MIB,and AMRC,Kyushu University+1 种基金by AMED JP23gm1910004,JP23jf0126004,24zf0127012,JSPS KAKENHIJP25H01009Ono Pharmaceutical Foundation for Oncology,Immunology and Neurology,and the Takeda Science Foundation.
文摘Spinal cord injury(SCI)is a severe neurological condition with limited regenerative capacity and no effective curative treatments.Interleukin-13(IL-13),an immunomodulatory cytokine,has shown therapeutic potential by promoting alternative immune activation and improving recovery after SCI in mice.However,cellbased IL-13 delivery is hindered by poor graft survival and limited localisation at the injury site.Here,we developed an injectable hydrogel-based delivery system(HGIL13)composed of IL-13-loaded poly(lactic-co-glycolic acid)(PLGA)microparticles embedded in a photocrosslinkable gelatin methacrylate(GelMA)matrix,enabling sustained and localised IL-13 release.HGIL13 achieved IL-13 release for up to six weeks and significantly reduced lipopolysaccharide(LPS)-induced inflammation in BV2 microglia in vitro.In a mouse contusion SCI model,HGIL13 enhanced functional recovery,reduced lesion volume,and decreased demyelinated area.Using the Hexbtd^(Tomato)mouse we show that HGIL13 modulated the neuroimmune response by decreasing resident microglia density,downregulating CD86 expression,and upregulating Arginase-1 in both microglia and infiltrating monocyte-derived macrophages.RT-qPCR and RNA-seq analyses confirmed sustained immunomodulation over 28 days and indicated early reduction of activated microglia at 7 days post-injury as a key therapeutic mechanism.This study presents a safe,effective,and translatable strategy for localised cytokine delivery,demonstrating strong potential for immunomodulation and improved functional recovery following SCI.
基金supported by the grants(2015K1A1A2032163,2020R1I1A1A01071828,2018K1A4A3A01064257,2021R1A5A2022318,2018R1D1A1B07048020),National Research Foundation(NRF),Republic of Korea.
文摘Polymeric hydrogels are fascinating platforms as 3D scaffolds for tissue repair and delivery systems of therapeutic molecules and cells.Among others,methacrylated gelatin(GelMA)has become a representative hydrogel formulation,finding various biomedical applications.Recent efforts on GelMA-based hydrogels have been devoted to combining them with bioactive and functional nanomaterials,aiming to provide enhanced physicochemical and biological properties to GelMA.The benefits of this approach are multiple:i)reinforcing mechanical properties,ii)modulating viscoelastic property to allow 3D printability of bio-inks,iii)rendering electrical/magnetic property to produce electro-/magneto-active hydrogels for the repair of specific tissues(e.g.,muscle,nerve),iv)providing stimuli-responsiveness to actively deliver therapeutic molecules,and v)endowing therapeutic capacity in tissue repair process(e.g.,antioxidant effects).The nanomaterial-combined GelMA systems have shown significantly enhanced and extraordinary behaviors in various tissues(bone,skin,cardiac,and nerve)that are rarely observable with GelMA.Here we systematically review these recent efforts in nanomaterials-combined GelMA hydrogels that are considered as next-generation multifunctional platforms for tissue therapeutics.The approaches used in GelMA can also apply to other existing polymeric hydrogel systems.
基金This work was supported by National Natural Science Foundation of China(81871805,81925027 and 32130059)Jiangsu Provincial Clinical Orthopedic Center,Key Laboratory of Stem Cells and Biomedical Materials of Jiangsu Province and Chinese Ministry of Science and Technology,the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘The dynamic extracellular matrix(ECM)constantly affects the behaviors of cells.To mimic the dynamics of ECM with controllable stiffness and energy dissipation,this study proposes a strategy in which a small molecule,3,4-dihydroxybenzaldehyde(DB),was used as fast"dynamic bridges"to construct viscoelastic gelatin methacryloyl(GelMA)-based hydrogels.The storage modulus and loss modulus of hydrogels were independently adjusted by the covalent crosslinking density and by the number of dynamic bonds.The hydrogels exhibited self-healing property,injectability,excellent adhesion and mechanical properties.Moreover,the in vitro results revealed that the viscous dissipation of hydrogels favored the spreading,proliferation,osteogenesis and chondrogenesis of bone marrow mesenchymal stem cells(BMSCs),but suppressed their adipogenesis.RNA-sequencing and immunofluorescence suggested that the viscous dissipation of hydrogels activated Yes-associated protein(YAP)by stabilizing integrinβ1,and further promoted nuclear translocation of smad2/3 andβ-catenin to enhance chondrogenesis and osteogenesis.As a result,the viscoelastic GelMA hydrogels with highest loss modulus showed best effect in cartilage and subchondral bone repair.Taken together,findings from this study reveal an effective strategy to fabricate viscoelastic hydrogels for modulating the interactions between cells and dynamic ECM to promote tissue regeneration.
基金supported by a grant from the National Research Foundation of Korea funded by the Ministry of education,Science,and Technology(MEST)(Grant NRF-2018R1A2B2005263)supported by the National Research Foundation of Korea(NRF)Grant funded by the Ministry of Science and ICT for Bioinspired Innovation Technology Development Project(NRF-2018M3C1B7021997)supported by a grant from the Ministry of Trade,Industry&Energy(MOTIE,Korea)under Industrial Technology Innovation Program(20009652:Technology on commercialization and materials of Bioabsorbable Hydroxyapatite that is less than micrometer in size).
文摘Volumetric muscle loss(VML)is associated with a severe loss of muscle tissue that overwhelms the regenerative potential of skeletal muscles.Tissue engineering has shown promise for the treatment of VML injuries,as evidenced by various preclinical trials.The present study describes the fabrication of a cell-laden GelMa muscle construct using an in situ crosslinking(ISC)strategy to improve muscle functionality.To obtain optimal biophysical properties of the muscle construct,two UV exposure sources,UV exposure dose,and wall shear stress were evaluated using C2C12 myoblasts.Additionally,the ISC system showed a significantly higher degree of uniaxial alignment and myogenesis compared to the conventional crosslinking strategy(post-crosslinking).To evaluate the in vivo regenerative potential,muscle constructs laden with human adipose stem cells were used.The VML defect group implanted with the bio-printed muscle construct showed significant restoration of functionality and muscular volume.The data presented in this study suggest that stem cell-based therapies combined with the modified bioprinting process could potentially be effective against VML injuries.
