Localized trans-browning and pro-angiogenesis inductive self-assembled collagen resveratrol bio-matrix for tissue repair and regeneration in obese conditions

The present study probes into the complexities of wound management in obesity by proposing a novel biomaterial designed to reprogram the altered skin physiology prevalent in obese conditions. The strategy involves the development of a multifunctional biomaterial addressing issues such as excessive exudate, pressure ulcers, and reduced vascularity. The bio-matrix demonstrates the localized transformation of white adipocytes through trans-browning, coupled with the simultaneous induction of angiogenesis at obese wound sites, resulting in expedited wound closure. The collagen bio-matrices, stabilized with Resveratrol (Rsv), exhibit remarkable thermal, mechanical, and biological stability. The porous 3D microstructure of the Rsv-stabilized collagen bio-matrix closely resembled the natural extracellular matrix, facilitating effective cell adhesion. The bio-matrix exhibited the unique capability to induce localized thermogenesis in the subcutaneous fat layer while concurrently activating angiogenesis. In vivo wound healing studies conducted on DIO-C57BL6 mice demonstrated complete healing within 10 days, showcasing accelerated tissue regeneration, blood vessel formation, robust collagen deposition, and significant activation of browning in the subcutaneous adipose layer. This study introduces the concept of tailored regenerative biomaterials with the ability to reprogram the challenging wound environment associated with obesity. This innovative approach opens up new avenues for enhanced wound care strategies, particularly for bariatric patients.

Apigenin Self-Assembled Collagen Biomatrix for Reprogramming the Obese Wound Microenvironment for Its Management and Repair

Wound management in obesity is complicated by excessive exudates from wounded areas, pressure ulcerations due to stacking of the fat layer, and vascular rarefaction. The current study explored the development of biomaterials for reprogramming the altered wound microenvironment under obese conditions. Self-assembled collagen biomatrix with trans and de novo browning activator, apigenin, was fabricated as a soft tissue regenerative wound dressing material. The as-synthesized self-assembled collagen biomatrix exhibited excellent thermal, mechanical, and biological stability with a superior wound exudate absorption capacity. The apigenin self-assembled collagen biomatrix exhibited porous 3-D microstructure that mimicked the extracellular matrix that promoted cell adhesion and proliferation. The apigenin self-assembled collagen multifunctional biomatrix triggered adaptive localized thermogenesis in the subcutaneous fat layer, resulting in the activation of angiogenesis and fibroblast spreading and migration. The in vivo wound healing assay performed in DIO-C57BL6 mice showed faster tissue regeneration within 9 days, with well-defined neo-epidermis, blood vessel formation, thick collagen deposition, minimal inflammation, and significant activation of browning in the subcutaneous adipose layer. This study paves the way forward for the development of specialized regenerative biomatrices that reprogram the obese wound bed for faster tissue regeneration.

Caffeine-reinforced Collagen as Localized Microenvironmental Trans-Browning Bio-Matrix for Soft Tissue Repair and Regeneration in Bariatric Condition

The wound exudates, hypoperfusion of the subcutaneous fat layer, and poor vasculature worsen wound management in obese subjects. In the current study, a multifunctional Caffeine-reinforced collagen biomaterial is developed that can simultaneously modulate lipid metabolism and angiogenesis in obese wound microenvironments for faster tissue regeneration. The biomaterial is fabricated specialized for obese conditions to initiate simultaneous lipolysis and angiogenesis locally in the hypoxic subcutaneous fat in wound margins of obese subjects. Caffeine-reinforced collagen biomatrix shows better structural integrity, thermal stability, bio-compatibility, and lesser proteolytic susceptibility. Caffeine-collagen biomaterial promote angiogenesis, fibroblast migration, and localized browning of white adipocytes to activate thermogenesis in the subcutaneous fat layer at the wound site. Full-thickness excision wound healing studies performed in obese C57BL6 mice shows faster wound closure within day 9 when compare to control mice. The Caffeine-reinforced collagen biomaterial remodeled the wound site locally by activating fibroblast to secrete collagen, activate endothelial cells to promote angiogenesis, and induce browning in white adipocytes in subcutaneous fat. The study opens a new direction in bariatric tissue regenerative medicine by locally modulating lipid metabolism, angiogenesis, and trans-browning at the injured site for faster complete restoration of the damaged tissue.

Microwave-assisted synthesis of crosslinked ureido chitosan for hemostatic applications

In this study, we present a facile method for introducing hydrophilic ureido groups (NH2-CO-NH-) into chitosan using a microwave-assisted reaction with molten urea, with the aim of enhancing chitosan's interaction with blood components for improved hemostasis. The formation of the ureido groups through nucleophilic addition reaction between the amine groups in chitosan and in situ generated isocyanic acid was confirmed by FTIR, CP/TOSS 13C NMR, and CP/MAS 15N NMR spectroscopic techniques. However, in stark contrast to the glucans, the said modification introduced extensive crosslinking in chitosan. Spectroscopic studies identified these crosslinks as carbamate bridges (-NH-COO-), which were likely formed by the reaction between the ureido groups and hydroxyl groups of adjacent chains through an isocyanate intermediate. These carbamate bridges improved ureido chitosan's environmental stability, making it particularly resistant to changes in pH and temperature. In comparison to chitosan, the crosslinked ureido chitosan synthesized here exhibited good biocompatibility and cell adhesion, rapidly arrested the bleeding in a punctured artery with minimal hemolysis, and induced early activation and aggregation of platelets. These properties render it an invaluable material for applications in hemostasis, particularly in scenarios that necessitate stability against pH variations and degradation.

In vivosoft tissue regenerative potential of flax seed mucilage self-assembled collagen aerogels

The present study demonstrates thein vivosoft tissue regenerative potential of flax seed mucilage (FSM) reinforced collagen aerogels in Wistar rats. The physiochemical, mechanical, and thermal properties were significantly improved upon the incorporation of flax mucilage into collagen when compared to the native collagen scaffold. In addition, the functional group of flax mucilage notably contributed to a better anti-oxidative potential than the control collagen. The flax mucilage-reinforced collagen at 4 mg ml-1concentration showed a 2-fold increase in porosity compared to native collagen. The tensile strength of native collagen, 2 mg ml-1, and 4 mg ml-1FSM reinforced collagen was 5.22 MPa, 9.76 MPa, and 11.16 MPa, respectively, which indicated that 2 mg ml-1and 4 mg ml-1FSM showed an 87% and 113% percentage increase respectively in tensile strength compared to the native collagen control. FSM-reinforced biomatrix showed 97% wound closure on day 15 post-wounding, indicating faster healing than controls, where complete healing occurred only on day 21. The mechanical properties of skin treated with FSM-reinforced collagen scaffold post-healing were considerably better than native collagen. The histological and immunohistochemistry analysis also showed complete restoration of wounded tissue like intact normal skin. The findings paved the way for the development of collagen-polysaccharide mucilage wound dressing materials and their further application in skin tissue engineering.

Modulation of angiogenic switch in reprogramming browning and lipid metabolism in white adipocytes

Thermogenic activation via trans-and de novo browning of white adipocytes is a promising strategy to accelerate lipid metabolism for regulating obesity-related disorders. In this study, we investigated the intricate interplay between angiogenic regulation and browning in white adipocytes using the bioactive compound, resveratrol (Rsv). Rsv has previously been documented for its regulatory influence on the trans and de novo browning of white adipocytes. Our findings revealed that concurrent activation of angiogenesis is prerequisite for inducing browning within the microenvironment of white adipocytes when exposed to browning activators. Additionally, we observed a significant browning effect on white adipocytes when the local adipose tissue environment was prompted to undergo angiogenesis, notably facilitated by a proangiogenic molecule known as Vascular endothelial growth factor (VEGF). Intriguingly, this effect was reversed when angiogenesis was inhibited by treatment with the antiangiogenic agent thalidomide. Furthermore, the study revealed the role of VEGF in paracrine activation of white adipocytes resulting in the induction of browning in both 3T3-L1 cell lines and primary mouse white adipocytes. The cross-talk between angiogenesis and browning was found to be initiated via the transcriptional activation of Estrogen receptor α (ERα) triggering the VEGF/VEGFR2 signaling pathway leading to browning and a reconfiguration of lipid metabolism within adipocytes. In conclusion, this study sheds light on the intricate cross-talk between angiogenesis and browning of white adipocytes. Notably, the findings underscore the reciprocal relationship between these processes, wherein inhibition of one process exerts discernible effects on the other.

Lanthanum Oxide Nanoparticles Reinforced Collagen ƙ-Carrageenan Hydroxyapatite Biocomposite as Angio-Osteogenic Biomaterial for In Vivo Osseointegration and Bone Repair

A composite biomatrix fabricated with collagen, ƙ-carrageenan, hydroxyapatite reinforced with lanthanum oxide nanoparticles is explored as proangiogenic and osteogenic bone tissue repair biomaterial. The biomatrix shows increased physical and biological stability as observed from proteolytic degradation and thermal stability studies. The addition of lanthanum oxide nanoparticles facilitates good osseointegration coupled with simultaneous activation of proangiogenic properties to act as a bone mimicking material. The minimal level of reactive oxygen species and superior cytocompatibility help the as-synthesized biomatrix in achieving capillary migration into the bone micro environment. The composite biomatrix upregulates the expression of VEGF, VEGF-R2 genes in endothelial cells and osteopontin, osteocalcin in osteoblasts cells, respectively. The in vivo hard tissue repair experiment conducted in a rat model shows complete healing of the bone defect by eight weeks with the application of collagen-ƙ-carrageenan-hydroxyapatite-lanthanum oxide nanoparticle biomaterial when compared to the biomaterial made out of individual constituents alone. The biomaterial matrix gets biointegrated into the bone tissue and exerts its therapeutic value in bringing a faster osseo repair process. The study shows the feasibility of using rare-earth metal nanoparticles in combination with protein-polysaccharide biopolymers for bone regeneration.

White to brown adipocyte transition mediated by Apigenin via VEGF-PRDM16 signaling

The dysregulated energy metabolism in white adipose tissues results in derangement of biological signaling resulting in obesity. Lack of vascularization in these white adipose tissues is one of the major reasons for dysregulated energy metabolism. Not much work has been done in this direction to understand the role of angiogenesis in white adipose tissue metabolism. In the present study, we evaluated the effect of angiogenic modulator in the metabolism of white adipocyte (WAC). Bioactive Apigenin was selected and its angiogenic ability was studied. Apigenin was shown to be highly proangiogenic hence the effect of Apigenin on de novo and trans-differentiation of WAT was studied. Apigenin showed enhanced de novo differentiation and trans-differentiation of mouse WAC into brown-like phenotype. To understand the effect of Apigenin on adipose tissue vasculature, coculture studies were conducted. Cross talk between endothelial cell and adipocytes were observed in coculture studies. Gene expression studies of cocultured cells revealed that browning of WAC occurred by triggering the expression of Vascular endothelial growth factor A. The study provides a new insight for inducing metabolic shift in WACs by modulation of angiogenesis in WAC microenvironment by the upregulation of PRDM16 cascade to trigger browning for the treatment of obesity.

Lanthanum oxide nanoparticle-collagen bio matrix induced endothelial cell activation for sustained angiogenic response for biomaterial integration

Rare earth lanthanum oxide nanoparticle reinforced collagen biomatrix that elicited the endothelial cell activation to promote angiogenesis for biomaterial integration was developed and evaluated in the present study. The structural integrity of collagen was not compromised on crosslinking of lanthanum oxide nanoparticle to collagen biomolecule. As-synthesised collagen biomatrix was shown to have improved mechanical strength, a lesser susceptibility to proteolytic degradation and good swelling properties. Superior cytocompatibility, hemocompatibility and minimal ROS generation was observed with Lanthanum oxide nanoparticle reinforced collagen bio matrix. The Lanthanum oxide nanoparticle reinforced collagen bio matrix elicited endothelial cell activation eliciting pro-angiogensis as observed in tube formation and aortic arch assays. The bio-matrix promoted the infiltration and proliferation of endothelial cells which is an unexplored domain in the area of tissue engineering that is very essential for biomaterial integration into host tissue. The wound healing effect of Lanthanum oxide nanoparticle stabilized collagen showed enhanced cell migration in vitro in cells maintained in Lanthanum oxide nanoparticle reinforced collagen bio matrix. The study paves the way for developing rare earth-based dressing materials which promoted biomatrix integration by enhancing vascularisation for tissue regenerative applications in comparison with traditional biomaterials.

Rationally designed Shewanella oneidensis Biofilm Toilored Graphene-Magnetite Hybrid Nanobiocomposite as Reusable Living Functional Nanomaterial for Effective Removal of Trivalent Chromium

Sustainable treatment of wastewater containing trivalent chromium (Cr³⁺) remains a significant challenge owing to the several limitations of the existing methodologies. Herein, combination of biosynthesis and Response Surface Methodology (RSM) for the fabrication and optimization of Shewanella oneidensis biofilm functionalized graphene-magnetite (GrM) nanobiocomposite was adopted as a 'living functional nanomaterial' (viz. S-GrM) for effective removal of Cr³⁺ ions from aqueous solution. In the biosynthetic process, S. oneidensis cells reduced the GO-akaganeite complex and adhered on the as-synthesized GrM nanocomposite to form S-GrM hybrid-nanobiocomposite. The process parameters for fabrication of S-GrM hybrid-nanobiocomposite was optimized by RSM based on four responses of easy magnetic separation, biofilm formation along with protein, and carbohydrate contents in extracellular polymeric substances (EPS). The morphology and chemical composition of S-GrM hybrid-nanobiocomposite were investigated using various spectroscopic and microscopic analyses and subsequently explored for removal of Cr³⁺ ions. The hybrid-nanobiocomposite effectively removed 304.64 ± 14.02 mg/g of Cr³⁺ at pH 7.0 and 30 °C, which is found to be very high compared to the previously reported values. The high surface area of graphene, biofilm biomass of S. oneidensis and plenty of functional groups provided a unique structure to the S-GrM hybrid-nanobiocomposite for efficient removal of Cr³⁺ through synergistic interaction. The FTIR and zeta potential studies confirmed that electrostatic and chelation/complexation reaction played key roles in the adsorption process. The fabrication of S-GrM nanobiocomposite thus creates a novel hybrid 'living functional nanomaterial' for low cost, recyclable, and sustainable removal of Cr³⁺ from wastewater.

Modular mucopolysaccharide gelatin naturapolyceutics hydrocolloid biomatrix with cobalt nano-additives for high density vascular network assembly

The present study demonstrates the development of polysaccharide gelatin naturapolyceutics hydrocolloidal biomatrix with cobalt nano-additives for restructuring native tissue vasculature for tissue regenerative applications. The engineered Gelatin/Aloevera mucilage polysaccharide/nanoscaled Cobalt (GAC) hydrocolloids resulted from the intermolecular interactions between the aloevera mucilage, cobalt nano-therapeutic and gelatin. GAC hydrocolloid showed enhanced thermal stability in comparison with control Gelatin/Aloevera mucilage (GA) hydrocolloid. FTIR analysis validated that the reinforcement of aloevera mucilage and cobalt nano-therapeutic did not affect the structural integrity of the gelatin molecule. 3-Dimensional sponge-like orientation of GAC hydrocolloid facilitates perfusable biomatrix for access to nutrients and gaseous exchange for high cell adhesion and proliferation. The combined therapeutic efficacy of mucilage polysaccharides, biodegradable nanoscaled cobalt and bio-polymer enhanced the pro-angiogenic capability of the hydrocolloids by stimulating Vascular Endothelial Growth Factor (VEGF) response at wounded tissue for faster healing. The experimental outcomes on in vivo angiogenesis profiling further confirmed the development of micro vessel in chick embryonic model and regeneration of blood vessels in zebra fish model. This study opens up the potential of mucilage polysaccharides in stimulating high density angiogenesis and conveys the progress of a biocompatible, biodegradable mucilaginous hydrocolloid as an effective bio-adhesive for vascular development in soft tissue regeneration.

Nanotized praseodymium oxide collagen 3-D pro-vasculogenic biomatrix for soft tissue engineering

The current study explores development of highly vascularizable biomatrix scaffold containing rare-earth metal praseodymium oxide nanoadditives for angiogenic and soft tissue regenerative applications. The therapeutic potential of praseodymium oxide nanoparticles rendered excellent endothelial cell differentiation for inducing pro angiogenic microenvironment by eliciting VE-Cadherin expression in the biomatrix scaffold. The nanoparticles were incorporated into bio-macromolecule collagen which aided in stabilization of collagen by maintaining the structural integrity of collagen and showed less susceptibility towards protease enzymes, high cyto-compatibility and high hemo-compatibility. The scaffold provided 3-dimensional micro-environments for the proliferation of endothelial cells and fibroblast cells promoting the wound healing process in an orchestrated fashion. Biological signal modulatory property of rare earth metal is the unexplored domains that can essentially bring significant therapeutic advancement in engineering advanced biological materials. This study opens potential use of nano-scaled rare earth metals in biomaterial application for tissue regeneration by modulating the pro-angiogenesis and anti-proteolysis properties.

Effect of magnesium ascorbyl phosphate on collagen stabilization for wound healing application

Wound healing is a complex process which requires appropriate structural support for restoration of tissue continuity and function. Collagen can act as a template for cellular activities but poor physico-chemical properties necessitates the stabilization of collagen without impairing its structure and function. This study investigates the effect of magnesium ascorbyl phosphate (MAP) on collagen with reference to physico-chemical properties. Incorporation of MAP enhanced the rate of collagen fibrillation signifying increased interaction at reduced time interval. MAP did not induce any changes in the secondary structure of collagen while there was an increase in shear viscosity with increase in shear stress at different shear rate. MAP stabilized collagen film exhibited higher denaturation temperature and showed an increase in Young's Modulus when compared with that of collagen film. In vivo studies showed complete wound closure on day 16 in case of stabilized collagen film. Mechanical properties of healed skin revealed that MAP collagen film treated rat skin completely regained its properties similar to that of normal skin thereby making them a potential candidate for wound healing application.

3 D nano bilayered spatially and functionally graded scaffold impregnated bromelain conjugated magnesium doped hydroxyapatite nanoparticle for periodontal regeneration

Chronic periodontal disease affect the tissues supporting around the teeth like gingival tissue, connective tissue, alveolar bone and periodontal ligaments. Hitherto, periodontal treatment was targeted to selectively repopulate the defect site with cell that has capability to regenerate lost tissue by promoting the concept of guided tissue regeneration but it requires second surgery due to non- biodegradability. The use of polymeric biodegradable nanofibrous coated scaffold that have the ability to deliver bioactives required for regeneration to occur is relatively a newer concept. The functionalization of polymeric scaffold with Bromelain and magnesium doped hydroxyapatite nanoparticle enhanced the mechanical, physico-chemical, thermal and biological properties of the scaffold by imitating the intricate extracellular matrix (ECM) architecture which provided the necessary bioactive cues that offered control over cellular functions by showing antibacterial potential, hemocompatibility and increasing the proliferation and migration rate in vitro. In addition, in ovo chicken chorioallantoic membrane assay and ex vivo aortic ring assay confirmed the efficacy of the developed scaffold by encouraging angiogenesis required for maintaining its viability after implanting onto the infected area. Further, the scaffold positively interacted with the host and actively contributed to the process of tissue regeneration in vivo in Wistar rat model.

Electrospun gelatin-polyethylenimine blend nanofibrous scaffold for biomedical applications

In this study, gelatin-polyethylenimine blend nanofibers (GEL/PEI) were fabricated via electrospinning with different ratios (9:1, 6:1, 3:1) to integrate the properties of both the polymers for evaluating its biomedical application. From scanning electron microscopy, the average diameter of blend nanofibers (265 ± 0.074 nm to 340 ± 0.088 nm) was observed to be less than GEL nanofibers (403 ± 0.08 nm). The incorporation of PEI with gelatin resulted in improved thermal stability of nanofibers whereas the Young's modulus was observed to be higher at 9:1 ratio when compared with other ratios. The in vitro studies showed that the GEL/PEI nanofibers with 9:1 ratio promoted better cell adhesion and viability. GEL/PEI nanofibers with 9:1 and 6:1 showed hemolysis within the permissible limits. From the results, it could be interpreted that GEL/PEI nanofibers with 9:1 ratio proved to be a better scaffold thereby making them a potential candidate for tissue engineering applications.

Pyrene-phenylglycinol linked reversible ratiometric fluorescent chemosensor for the detection of aluminium in nanomolar range and its bio-imaging

Pyrene-phenylglycinol tangled ratiometric sensor (R)-1 was developed for the detection of Al³⁺ ion over other metal ions. Ratiometric behaviour of (R)-1 for Al³⁺ ion explained through monomer emission and excimer quenching leads to avoiding the π-π interactions of bis-pyrene rings. Pull-push to push-pull binding mechanism is successfully explained by DFT and sensing of Al³⁺-ions demonstrated in living cells. The LOD of (R)-1 for Al³⁺ downs to nanomolar concentrations which is lower than the allowed concentration of drinking water set by the (World Health Organization) WHO.

Nanoscaled Biodegradable Metal-Polymeric Three-Dimensional Framework for Endothelial Cell Patterning and Sustained Angiogenesis

The current work describes the development of a nanoscaled biodegradable metal polymeric three-dimensional framework with controlled nanotherapeutic release for endothelial cell patterning and sustained angiogenesis for biomedical applications. Biocompatible polymers gelatin and PLGA were used as polymeric nanofibrous three-dimensional framework in a core-shell manner with the gelatin core containing a biodegradable and bioactive metal nanoframework of cobalt caged with PEGylated curcumin by coaxial electrospinning. FTIR results confirmed the presence of nanobioactives in the core region of a coaxial nanofiber. Scanning electron microscopic analysis of the coaxial nanofibrous system showed a three-dimensional architecture that favored endothelial cell adhesion, patterning, migration, and proliferation. The as-synthesized nanoscaled biodegradable metal polymeric three-dimensional core-shell nanofibers exhibited potent antibacterial efficacy. Further, it improved the endothelial cell patterning promoting angiogenesis. The high therapeutic potential of cobalt nanoframework in the nanofibers enhanced the production of vascular endothelial growth factor promoting angiogenesis that resulted in the earlier restoration of wounded tissue compared with untreated control in vivo animal models. The study opens up a new horizon in exploring biodegradable biosorbable metal nanoframework for biomaterial applications. Additionally, the present study opens up a new strategy in developing biodegradable biosorbable biomaterial with enhanced vascularization efficacy to the biomaterial, which is important for acceptance of these biomaterials into the host tissue.

Fabrication of plumbagin on silver nanoframework for tunable redox modulation: Implications for therapeutic angiogenesis

The redox state of the endothelial cells plays a key role in the regulation of the angiogenic process. The modulation of the redox state of endothelial cells (ECs) could be a viable target to alter angiogenic response. In the present work, we synthesized a redox modulator by caging 5-hydroxy 2-methyl 1, 4-napthoquinone (Plumbagin) on silver nano framework (PCSN) for tunable reactive oxygen species (ROS) inductive property and tested its role in ECs during angiogenic response in physiological and stimulated conditions. In physiological conditions, the redox modulators induced the angiogenic response by establishing ECs cell-cell contact in tube formation model, chorio allontoic membrane, and aortic ring model. The molecular mechanism of angiogenic response was induced by vascular endothelial growth factor receptor 2 (VEGFR2)/p42-mitogen-activated protein kinase signaling pathway. Under stimulation, by mimicking tumor angiogenic conditions it induced cytotoxicity by generation of excessive ROS and inhibited the angiogenic response by the loss of spatiotemporal regulation of matrix metalloproteases, which prevents the tubular network formation in ECs and poly-ADP ribose modification of VEGF. The mechanism of opposing effects of PCSN was due to modulation of PKM2 enzyme activity, which increased the EC sensitivity to ROS and inhibited EC survival in stimulated condition. In normal conditions, the endogenous reactive states of NOX4 enzyme helped the EC survival. The results indicated that a threshold ROS level exists in ECs that promote angiogenesis and any significant enhancement in its level by redox modulator inhibits angiogenesis. The study provides the cues for the development of redox-based therapeutic molecules to cure the disease-associated aberrant angiogenesis.

Selectivity and sensitivity of molybdenum oxide-polycaprolactone nanofiber composites on skin cancer: Preliminary in-vitro and in-vivo implications

Cancer nanomedicine has emerged as a revolution in the last decade opening up promising strides for the cancer treatment. The major challenge in these therapeutic approaches resides in the failure of clinical trials owing to the immunological cancer microenvironment. Therefore, the success of next generation nanomedicine depends on tunable physicochemical nanomaterial design and corresponding clinical trials by integrating targeted delivery with mitigated toxicity. The present study deals with the fabrication of nanofibrous scaffold impregnated with molybdenum nanoparticles for targeted skin cancer therapeutics. Molybdenum oxide, a transitional metal oxide is gaining rapid importance due to its vital role in cellular and molecular metabolism. Polycaprolactone nanofibers were chosen as a matrix to localize the nanoparticles topically facilitating selective apoptosis of the tumor cells over the normal cells with mitigated side effects. The scaffold was designed to tailor the physicochemical, mechanical and biological suitability for skin cancer (melanoma and non melanoma). The designed scaffold was found to reduce more than 50% cell viability of the cancer cells selectively through apoptosis as confirmed using AO/PI staining and the probable mechanism could be attributed to the induction of mitochondria dependent apoptosis as observed by JC1 dye staining. In-vivo trials in zebra fish were found to reduce cancer progression by more than 30% in 14 days. The fabricated molybdenum trioxide nano constructs not only serve as tunable targeted systems but also open venues capable of ferrying chemotherapeutic drugs sparing normal cells alleviating the trauma due to side effects.

Strategic design of cardiac mimetic core-shell nanofibrous scaffold impregnated with Salvianolic acid B and Magnesium l-ascorbic acid 2 phosphate for myoblast differentiation

The major loss of myocardial tissue extracellular matrix after infarction is a serious complication that leads to heart failure. Regeneration and integration of damaged cardiac tissue is challenging since the functional restoration of the injured myocardium is an incredible task. The injured micro environment of myocardium fails to regenerate spontaneously. The emergence of nano-biomaterials would be a promising approach to regenerate such a damaged cardiomyocytes tissue. Here, we have fabricated a dual bioactive embedded nanofibrous cardiac patch via coaxial electrospinning technique, to mimic the topographical and chemical cues of the natural cardiac tissue. The proportion and the concentration of the polymers were optimized for tailored delivery of bioactives from a spatio-temporally designed scaffold. The functionalization of polymeric core shell nanofibrous scaffold with dual bioactives enhanced the physico-chemical and bio-mechanical properties of the scaffolds that has resulted in a 3-dimensional topography mimicking the natural cardiac like extracellular matrix. The sustained delivery of bioactive signals, improved cell adhesion, proliferation, migration and differentiation could be attributed to its highly interconnected nanofibrous matrix with good extended morphology. Further, the expression of cardiac specific markers were found to increase on investigation of mRNA by real time PCR studies and proteins by immunofluorescence and western blotting techniques, confirming cell - biomaterial interactions. Flow cytometry analysis authenticated a potent mitochondrial membrane potential of cells treated with nanocomposite. In addition, in ovo studies in chicken chorioallantoic membrane assay confirm the efficacy of the developed scaffold in inducing angiogenesis required for maintaining its viability after transplantation onto the infarcted zone. These promising results demonstrate the potential of the composite nanofibrous scaffold as an effective biomaterial substrate for cardiac regeneration providing cues for development of novel cardiac therapeutics.

Fabrication of Nontoxic Reduced Graphene Oxide Protein Nanoframework as Sustained Antimicrobial Coating for Biomedical Application

Bacterial colonization on medical devices is a major concern in the healthcare industry. In the present study, we report synthesis of environmental sustainable reduced graphene oxide (rGO) on the large scale through biosynthetic route and its potential application for antibacterial coating on medical devices. HRTEM image depicts formation of graphene nanosheet, while DLS and ζ potential studies reveal that in aqueous medium the average hydrodynamic size and surface charge of rGO are 4410 ± 116 nm and -25.2 ± 3.2 mV, respectively. The Raman, FTIR, and XPS data suggest in situ conjugation of protein with rGO. The as-synthesized rGO protein nanoframework exhibits dose-dependent antibacterial activity and potential of killing of 94% of Escherichia coli when treated with 80 μg/mL of rGO for 4 h. The hemolytic and cytotoxicity studies demonstrate that rGO protein nanoframework is highly biocompatible at the same concentration showing significant antimicrobial properties. The rGO coated on the glass surface obtained through covalent bonding exhibits potent antibacterial activity. Antibacterial mechanism further demonstrates that rGO-protein nanoframework in dispersed state (rGO solution) exerts bactericidal effect through physical disruption accompanied by ROS-mediated biochemical responses. The rGO subsequently entering into the cytoplasm through the damaged membrane causes metabolic imbalance in the cells. In sharp contrast, physical damage of the cell membrane is the dominant antibacterial mechanism of rGO in the immobilized state (rGO coated glass). The obtained results help indepth understanding of the antibacterial mechanism of the biosynthesized rGO and a novel way to develop nontoxic antibacterial coating on medical devices to prevent bacterial infection.

Fabrication of Hybrid Collagen Aerogels Reinforced with Wheat Grass Bioactives as Instructive Scaffolds for Collagen Turnover and Angiogenesis for Wound Healing Applications

The present study illustrates the progress of the wheat grass bioactive-reinforced collagen-based aerogel system as an instructive scaffold for collagen turnover and angiogenesis for wound healing applications. The reinforcement of wheat grass bioactives in collagen resulted in the design and development of aerogels with enhanced physicochemical and biomechanical properties due to the intermolecular interaction between the active growth factors of wheat grass and collagen fibril. Differential scanning calorimetry analysis revealed an enhanced denaturation temperature when compared to those of native collagen aerogels. Fourier transform infrared spectroscopy analysis confirmed that the reinforcement of bioactives in the wheat grass did not affect the structural integrity of the collagen molecule. Additionally, the reinforced biomaterial with a systematic absorptive morphology resulted in a three-dimensional (3D) sponge-like aerogel exhibiting a potent highly oriented 3D structural assembly that showed increased water retention ability and substance permeability that would enable the passage of nutrients and gaseous components for cellular growth. Furthermore, the cumulative effect of the growth factors in wheat grass and the collagen molecule augments the angiogenic ability and collagen production of the aerogel by restoration of the damaged tissue thereby making it a potential 3D wound dressing scaffold. The results were confirmed by in vivo wound healing assays. This study shows the possibility for progress of a biocompatible, biodegradable, and nonadhesive nutraceutical-reinforced collagen aerogel as an instructive scaffold with good antimicrobial properties for collagen turnover and angiogenic response for wound healing applications.

Role of nanoparticle size in self-assemble processes of collagen for tissue engineering application

Nanoparticle mediated extracellular matrix may offer new and improved biomaterial to wound healing and tissue engineering applications. However, influence of nanoparticle size in extracellular matrix is still unclear. In this work, we synthesized different size of silver nanoparticles (AgNPs) comprising of 10nm, 35nm and 55nm using nutraceuticals (pectin) as reducing as well as stabilization agents through microwave irradiation method. Synthesized Ag-pectin nanoparticles were assimilated in the self-assemble process of collagen leading to fabricated collagen-Ag-pectin nanoparticle based scaffolds. Physico-chemical properties and biocompatibility of scaffolds were analyzed through FT-IR, SEM, DSC, mechanical strength analyzer, antibacterial activity and MTT assay. Our results suggested that 10nm sized Ag-pectin nanoparticles significantly increased the denaturation temperature (57.83°C) and mechanical strength (0.045MPa) in comparison with native collagen (50.29°C and 0.011MPa). The in vitro biocompatibility assay reveals that, collagen-Ag-pectin nanoparticle based scaffold provided higher antibacterial activity against to Gram positive and Gram negative as well as enhanced cell viability toward keratinocytes. This work opens up a possibility of employing the pectin caged silver nanoparticles to develop collagen-based nanoconstructs for biomedical applications.

Curcumin cross-linked collagen aerogels with controlled anti-proteolytic and pro-angiogenic efficacy

This paper elucidates the development of a curcumin cross-linked collagen aerogel system with controlled anti-proteolytic activity and pro-angiogenic efficacy. The results of this study showed that in situ cross-linking of curcumin with collagen leads to the development of aerogels with enhanced physical and mechanical properties. The integrity of collagen after cross-linking with curcumin was studied via FTIR spectroscopy. The results confirmed that the cross-linking with curcumin did not induce any structural changes in the collagen. The curcumin cross-linked collagen aerogels exhibited potent anti-proteolytic and anti-microbial activity. Scanning electron and atomic force microscopic analysis of curcumin cross-linked collagen aerogels showed a 3D microstructure that enhanced the adhesion and proliferation of cells. The highly organized geometry of collagen-curcumin aerogels enhanced the permeability and water-retaining ability required for the diffusion of nutrients that aid cellular growth. The pro-angiogenic properties of collagen-curcumin aerogels were ascribed to the cumulative effect of the nutraceutical and the collagen molecule, which augmented the restoration of damaged tissue. Further, these aerogels exhibited controlled anti-proteolytic activity, which makes them suitable 3D scaffolds for biomedical applications. This study provides scope for the development of biocompatible and bioresorbable collagen aerogel systems that use a nutraceutical as a cross-linker for biomedical applications.

2-Deoxy Glucose Modulates Expression and Biological Activity of VEGF in a SIRT-1 Dependent Mechanism

Reprogramming of energy metabolism particularly switching over of cells to aerobic glycolysis leading to accumulation of lactate is a hallmark of cancer. Lactate can induce angiogenesis, an important process underlying tumor growth and metastasis. VEGF is one of the most important cytokines which regulate this process and the present study was designed to examine if blocking glycolytic pathway in tumor cells can affect its angiogenic potency with respect to VEGF. For this, the expression and biological activity of VEGF synthesized and secreted by tumor derived cell lines in the presence or absence of 2-deoxy glucose (2-DG), an inhibitor of glycolysis was determined. The results suggested that inhibition of glycolysis using sub-lethal doses of 2-DG down-regulated the expression of VEGF and also significantly reduced its biological activity. Further mechanistic studies revealed that the down regulation of VEGF gene expression by 2-DG was due to an increase in SIRT-1 activity and the reduced biological activity was found to be due to an increase in the PAR modification of VEGF. Activity of SIRT-1 and PAR modification of VEGF in turn, was found to be correlated to the cellular NAD⁺ levels. The results presented here therefore suggest that treatment of cancer cells with 2-DG can significantly reduce its overall angiogenic potency through transcriptional and post-translational mechanisms. J. Cell. Biochem. 118: 252-262, 2017. © 2016 Wiley Periodicals, Inc.

An emulsion of pigmented nanoceria as a medicinal cosmetic

In this work, SnO₂functionalized graphene oxide was shown to possess high adsorption capacities and fast adsorption rates for organic dyes over wide pH ranges. Additionally, the adsorbent could be easily regenerated by washing with ethanol.

An additional fluorenylmethoxycarbonyl (Fmoc) moiety in di-Fmoc-functionalized L-lysine induces pH-controlled ambidextrous gelation with significant advantages

In recent years, several fluorenylmethoxycarbonyl (Fmoc)-functionalized amino acids and peptides have been used to construct hydrogels, which find a wide range of applications. Although several hydrogels have been prepared from mono Fmoc-functionalized amino acids, herein, we demonstrate the importance of an additional Fmoc-moiety in the hydrogelation of double Fmoc-functionalized L-lysine [Fmoc(Nα)-L-lysine(NεFmoc)-OH, (Fmoc-K(Fmoc))] as a low molecular weight gelator (LMWG). Unlike other Fmoc-functionalized amino acid gelators, Fmoc-K(Fmoc) exhibits pH-controlled ambidextrous gelation (hydrogelation at different pH values as well as organogelation), which is significant among the gelators. Distinct fibrous morphologies were observed for Fmoc-K(Fmoc) hydrogels formed at different pH values, which are different from organogels in which Fmoc-K(Fmoc) showed bundles of long fibers. In both hydrogels and organogels, the self-assembly of Fmoc-K(Fmoc) was driven by aromatic π-π stacking and hydrogen bonding interactions, as evidenced from spectroscopic analyses. Characterization of Fmoc-K(Fmoc) gels using several biophysical methods indicates that Fmoc-K(Fmoc) has several advantages and significant importance as a LMWG. The advantages of Fmoc-K(Fmoc) include pH-controlled ambidextrous gelation, pH stimulus response, high thermal stability (∼100 °C) even at low minimum hydrogelation concentration (0.1 wt%), thixotropic property, high kinetic and mechanical stability, dye removal properties, cell viability to the selected cell type, and as a drug carrier. While single Fmoc-functionalized L-lysine amino acids failed to exhibit gelation under similar experimental conditions, the pH-controlled ambidextrous gelation of Fmoc-K(Fmoc) demonstrates the benefit of a second Fmoc moiety in inducing gelation in a LMWG. We thus strongly believe that the current findings provide a lead to construct or design various new synthetic Fmoc-based LMW organic gelators for several potential applications.

Effect of curcumin caged silver nanoparticle on collagen stabilization for biomedical applications

The current study aims at understanding the influence of curcumin caged silver nanoparticle (CCSNP) on stability of collagen. The results indicated that curcumin caged silver nanoparticles efficiently stabilize collagen, indicated by enhanced tensile strength, fibril formation and viscosity. The tensile strength of curcumin caged silver nanoparticle cross-linked collagen and elongation at break was also found to be higher than glutaraldehyde cross-linked collagen. The physicochemical characteristics of curcumin caged nanoparticle cross-linked collagen exhibited enhanced strength. The thermal properties were also good with both thermal degradation temperature and hydrothermal stability higher than native collagen. CD analysis showed no structural disparity in spite of superior physicochemical properties suggesting the significance of curcumin caged nanoparticle mediated cross-linking. The additional enhancement in the stabilization of collagen could be attributed to multiple sites for interaction with collagen molecule provided by curcumin caged silver nanoparticles. The results of cell proliferation and anti-microbial activity assays indicated that curcumin caged silver nanoparticles promoted cell proliferation and inhibited microbial growth making it an excellent biomaterial for wound dressing application. The study opens scope for nano-biotechnological strategies for the development of alternate non-toxic cross-linking agents facilitating multiple site interaction thereby improving therapeutic values to the collagen for biomedical application.

Fabrication of electrospun zein nanofibers for the sustained delivery of siRNA

In this study, zein nanofibers based siRNA delivery system has been attempted for the first time. Here, the amphiphilic property of zein and the size advantage of nanofibers have been brought together in developing an ideal delivery system for siRNA. The morphological analysis of the GAPDH-siRNA loaded zein nanofibers revealed the proper encapsulation of the siRNA in the polymeric matrix. The loading efficiency of this delivery system was found to be 58.57±2.4% (w/w). The agarose gel analysis revealed that the zein nanofibers preserved the integrity of siRNA for a longer period even at the room temperature. The in vitro release studies not only depicted the sustaining potential of the zein nanofibers but also ensured the release of sufficient quantity of siRNA required to induce the gene silencing effect. The amphiphilic property of zein supported the cell attachment and thereby facilitated the transfection of siRNA into the cells. qRT-PCR analysis confirmed the potential of the developed system in inducing the desired gene silencing effect. Thus, electrospun zein nanofibers have been successfully employed for the delivery of siRNA which has a great therapeutic potential.

Plumbagin caged silver nanoparticle stabilized collagen scaffold for wound dressing

Wound dressing material based on nano-biotechnological intervention by caging plumbagin on silver nanoparticle (PCSN) as a multi-site cross-linking agent of collagen scaffolds with potent anti-microbial and wound healing activity.

Nano-caged shikimate as a multi-site cross-linker of collagen for biomedical applications

Shikimic acid caged silver nanoparticles as multi-site cross-linkers of collagen for tissue engineering applications.

Design and development of papain–urea loaded PVA nanofibers for wound debridement

Nanofiber based delivery of enzyme for wound debridement with sustained functional integrity.

Caging of plumbagin on silver nanoparticles imparts selectivity and sensitivity to plumbagin for targeted cancer cell apoptosis

Nano-caging of plumbagin for selective killing of cancer cells.