Poly(L-lactic acid) nanofibers containing Cissus quadrangularis induced osteogenic differentiation in vitro

Phytofabrication of biocompatible chitosan-based ZnO nanocomposite aided by Cissus quadrangularis extract enriched with antimicrobial and antioxidant potential

A dynamic chitosan-based ZnO nanocomposite (NC) was fabricated via a cost-effective formulation and an eco-friendly procedure utilizing Cissus quadrangularis (CQ) plant extract. This study investigates the antimicrobial and antioxidant properties, together with the cytocompatibility aspects of chitosan-incorporated ZnO nanocomposite (CS-ZnO/CQE). The formation and structural morphology of the nanocomposites were examined using FTIR, UV-Vis, XRD, XPS, BET, TGA, SEM, and TEM techniques. The antibacterial test results demonstrated the greatest inhibitory zone diameter against S. aureus (19 ± 1.00 mm) and E. coli (17 ± 1.05 mm), assessed through agar well diffusion method. Also, the composite exhibited a DPPH inhibition rate of 78.7 ± 0.34 %, indicating its high effectiveness in neutralizing free radicals. In addition, the nanocomposite exhibited less toxicity towards human erythrocytes, HDF and HEK-293 cells as a result of the biocompatibility exhibited by CS, ZnO, and CQ plant extract. Likewise, it has exceptional cell migratory capacity and possesses biodegradability factors. These observations strongly suggest the potential of CS-ZnO/CQE as a cutting-edge antibacterial and antioxidant agent to be implemented in the medical sector.

Dissolving microneedles for alopecia treatment

Alopecia is a treatable benign disease, however, approximately 15-30% of women and 50% of men suffer from alopecia, which greatly affects patient's self-esteem and quality of life. Currently, commercial products for alopecia treatment include topical minoxidil solution, oral finasteride tablets and oral baricitinib tablets. However, the barrier of stratum corneum, systemic adverse effects and poor cure rate limit the application of commercial products. Therefore, researchers investigated the mechanism of alopecia, and developed new drugs that could target lactate dehydrogenase-related pathways, remove excessive reactive oxygen in hair follicles, and reduce the escape of hair follicle stem cells, thus injecting new strength into the treatment of alopecia. Moreover, starting from improving drug stratum corneum penetration and reducing side effects, researchers have developed hair loss treatment strategies based on dissolved microneedles (MNs), such as drug powders/microparticles, nanoparticles, biomimetic cell membranes, phototherapy and magnetically responsive soluble microneedles, which show exciting alopecia treatment effects. However, there are still some challenges in the practical application of the current alopecia treatment strategy with soluble microneedles, and further studies are needed to accelerate its clinical translation.

Enhanced osteogenic differentiation and mineralization of human dental pulp stem cells using Prunus amygdalus amara (bitter almond) incorporated nanofibrous scaffold

Polyphenol extracts derived from plants are expected to have enhanced osteoblast proliferation and differentiation ability, which has gained much attention in tissue engineering applications. Herein, for the first time, we investigate the effects of Prunus amygdalus amara (bitter almond) (BA) extract loaded on poly (ε-caprolactone) (PCL)/gelatin (Gt) nanofibrous scaffolds on the osteoblast differentiation of human dental pulp stem cells (DPSCs). In this regard, BA (0, 5, 10, and 15% wt)-loaded PCL/Gt nanofibrous scaffolds were prepared by electrospinning with fiber diameters in the range of around 237-276 nm. Morphology, composition, porosity, hydrophilicity, and mechanical properties of the scaffolds were examined by FESEM, ATR-FTIR spectroscopy, BET, contact angle, and tensile tests, respectively. It was found that the addition of BA improved the tensile strength (up to 6.1 times), Young's modulus (up to 3 times), and strain at break (up to 3.2 times) compared to the neat PCL/Gt nanofibers. Evaluations of cell attachment, spreading, and proliferation were done by FESEM observation and MTT assay. Cytocompatibility studies support the biocompatible nature of BA loaded PCL/Gt scaffolds and free BA by demonstrating cell viability of more than 100% in all groups. The results of alkaline phosphatase activity and Alizarin Red assay revealed that osteogenic activity levels of BA loaded PCL/Gt scaffolds and free BA were significantly increased compared to the control group (p < 0.05, p < 0.01, p < 0.001). QRT-PCR results demonstrated that BA loaded PCL/Gt scaffolds and free BA led to a significant increase in osteoblast differentiation of DPSCs through the upregulation of osteogenic related genes compared to the control group (p < 0.05). Based on results, incorporation of BA extract in PCL/Gt scaffolds exhibited synergistic effects on the adhesion, proliferation, and osteogenesis differentiation of hDPSCs and was therefore assumed to be a favorable scaffold for bone tissue engineering applications.

Recent Progress of Electrospun Herbal Medicine Nanofibers

Herbal medicine has a long history of medical efficacy with low toxicity, side effects and good biocompatibility. However, the bioavailability of the extract of raw herbs and bioactive compounds is poor because of their low water solubility. In order to overcome the solubility issues, electrospinning technology can offer a delivery alternative to resolve them. The electrospun fibers have the advantages of high specific surface area, high porosity, excellent mechanical strength and flexible structures. At the same time, various natural and synthetic polymer-bound fibers can mimic extracellular matrix applications in different medical fields. In this paper, the development of electrospinning technology and polymers used for incorporating herbal medicine into electrospun nanofibers are reviewed. Finally, the recent progress of the applications of these herbal medicine nanofibers in biomedical (drug delivery, wound dressing, tissue engineering) and food fields along with their future prospects is discussed.

Herbal nanomedicines: Recent advancements, challenges, opportunities and regulatory overview

BACKGROUND

Herbal Nano Medicines (HNMs) are nano-sized medicine containing herbal drugs as extracts, enriched fractions or biomarker constituents. HNMs have certain advantages because of their increased bioavailability and reduced toxicities. There are very few literature reports that address the common challenges of herbal nanoformulations, such as selecting the type/class of nanoformulation for an extract or a phytochemical, selection and optimisation of preparation method and physicochemical parameters. Although researchers have shown more interest in this field in the last decade, there is still an urgent need for systematic analysis of HNMs.

PURPOSE

This review aims to provide the recent advancement in various herbal nanomedicines like polymeric herbal nanoparticles, solid lipid nanoparticles, phytosomes, nano-micelles, self-nano emulsifying drug delivery system, nanofibers, liposomes, dendrimers, ethosomes, nanoemulsion, nanosuspension, and carbon nanotube; their evaluation parameters, challenges, and opportunities. Additionally, regulatory aspects and future perspectives of herbal nanomedicines are also being covered to some extent.

METHODS

The scientific data provided in this review article are retrieved by a thorough analysis of numerous research and review articles, textbooks, and patents searched using the electronic search tools like Sci-Finder, ScienceDirect, PubMed, Elsevier, Google Scholar, ACS, Medline Plus and Web of Science.

RESULTS

In this review, the authors suggested the suitability of nanoformulation for a particular type of extracts or enriched fraction of phytoconstituents based on their solubility and permeability profile (similar to the BCS class of drugs). This review focuses on different strategies for optimising preparation methods for various HNMs to ensure reproducibility in context with all the physicochemical parameters like particle size, surface area, zeta potential, polydispersity index, entrapment efficiency, drug loading, and drug release, along with the consistent therapeutic index.

CONCLUSION

A combination of herbal medicine with nanotechnology can be an essential tool for the advancement of herbal medicine research with enhanced bioavailability and fewer toxicities. Despite the challenges related to traditional medicine's safe and effective use, there is huge scope for nanotechnology-based herbal medicines. Overall, it is well stabilized that herbal nanomedicines are safer, have higher bioavailability, and have enhanced therapeutic value than conventional herbal and synthetic drugs.

Innovative Delivery Systems Loaded with Plant Bioactive Ingredients: Formulation Approaches and Applications

Plants constitute a rich source of diverse classes of valuable phytochemicals (e.g., phenolic acids, flavonoids, carotenoids, alkaloids) with proven biological activity (e.g., antioxidant, anti-inflammatory, antimicrobial, etc.). However, factors such as low stability, poor solubility and bioavailability limit their food, cosmetics and pharmaceutical applications. In this regard, a wide range of delivery systems have been developed to increase the stability of plant-derived bioactive compounds upon processing, storage or under gastrointestinal digestion conditions, to enhance their solubility, to mask undesirable flavors as well as to efficiently deliver them to the target tissues where they can exert their biological activity and promote human health. In the present review, the latest advances regarding the design of innovative delivery systems for pure plant bioactive compounds, extracts or essential oils, in order to overcome the above-mentioned challenges, are presented. Moreover, a broad spectrum of applications along with future trends are critically discussed.

Evaluation of bone healing activity of Cissus quadrangularis (Linn), Cryptolepis buchanani, and Sardinella longiceps in Wistar rats

Background

The object of the present study is to evaluate the effect of alcoholic extracts of Cissus quadrangularis (CQ), Cryptolepis buchanani (CB), and Sardinella longiceps (SL) either alone or in the combination (100 mg/kg) in the management of femur bone healing of Wistar albino rats for 8 weeks. After the period of treatment, femur bones were examined by using biochemical, radiographical, and histopathological studies.

Result

Biochemical evaluation results reveal that there is a steep increase of serum calcium level in the experimental animals during the entire period of treatment which led to an adequate supply of serum calcium to the fractured bone for healing and increases the thickness of the femur bones soon compared to control group. It had been estimated by a calibrated ocular micrometer. Radiographical images of the bones also disclose that the complete bridging of fractured bone occurred in the experimental animals after the treatment of natural compound extracts. In addition to that, all the organs of animals were safe in the experimental animals during the entire study.

Conclusion

The present study strongly recommended that these ethanolic extracts (CQCBSL) either alone or in the combination restoring the strength of the bone and reduced bone repairing period due to the rich content of calcium and other natural phytochemicals presents with them.

Graphical abstract

Effects of magnesium carbonate concentration and lignin presence on properties of natural cellulosic Cissus quadrangularis fiber composites

Cissus quadrangularis biodegradable natural cellulosic fibers comprehensively characterized to assess their potential as reinforcing materials in polymer composites. Initially, the Cissus quadrangularis fibers were chemically treated with 5% Sodium hydroxide (NaOH) and 5% magnesium carbonate (MgCO₃) to improvise the properties of the fiber. The mechanical test result shows that chemically treated 5% MgCO₃ fiber show that 4% and 24% improved tensile strength compared to NaOH and untreated ones. The cellulose crystallinity of the treated fiber got increased as the amorphous constituents removed. Further, 5% MgCO₃ treatment removed a larger amount of amorphous hemicellulose, lignin, and other impurities present on the fiber surface. Secondly, the composites were fabricated at different combination of MgCO₃ (5%, 10%, 15%), plasticizer (5%, 7.5%, 10%), and fiber volume (20%, 25% and 30%) with L9 Taguchi orthogonal array approach. Based on the results, 5% MgCO₃, 5% plasticizer, and 30% fiber volume showed significant improvement in Young's modulus, tensile, and flexural strength of 8%, 27%, and 16% respectively. Moreover, there was no notable improvement observed on impact strength for both treated (15.91 KJ/m²) and untreated (13.98 KJ/m²) fiber. The scanning electron microscopy (SEM) micrographs used to examine the interface bonding between fiber and the matrix.

Orthobiologics with phytobioactive cues: A paradigm in bone regeneration

Bone injuries occur due to various traumatic and disease conditions. Healing of bone injury occurs via a multi-stage intricate process. Body has the potential to rectify most of the bone injuries but some severe traumatic cases with critical size defects may require interventions. Autografts are still considered the "gold standard" for fracture healing but due to limitations associated with it, new alternatives are warranted. The field of orthobiologics has provided novel approaches using scaffolds, bioactive molecules, stem cells for the treatment of bone defects. Phyto-bioactives have been widely used in alternative medicine and folklore practices for curing bone ailments. It is believed that different bioactive constituents in plants work synergistically to give the therapeutic efficacy. Bioactives in plants extracts act upon different signal transduction pathways aiding in bone healing. The present review focuses on the use, chemical composition, mode of delivery, mechanism of action, and possible future strategies of three medicinal plants popularly used in traditional medicine for bone healing: Cissus quadrangularis, Withania somnifera and Tinospora cordifolia. Plants extracts seem to be a natural and non-toxic therapeutic alternative in treating bone injuries. Most of the studies on bone healing for these plants have reported oral administration of the extracts and presented them as a safe alternative without any side effects despite giving higher doses. Forthcoming studies could be directed towards the local delivery of extracts at the defect site. Unification of herbal extracts and orthobiologics could be an interesting direction in the field of bone healing in future. The present review intends to provide a bird's eye view of different strategies used in bone healing, mechanisms involved and future direction of advancements using phytobioactives and orthobiologics.

Decellularization and oxidation process of bamboo stem enhance biodegradation and osteogenic differentiation

Many features that are appropriate for an ideal tissue engineered biomaterial are found in plant tissues. Hierarchically organized Bambusa vulgaris exhibits structural similarities to native bone, but the degradation of cellulose that is the main component of the plant cell wall is a challenge. In this study, Bamboo stem was subjected to decellularization followed by a chemical oxidation process (treated with sodium periodate) to enhance biocompatibility and biodegradation. The crystallinity of oxidised plant scaffolds was reduced, resulting in lower mechanical strength. In contrast, hydrophilicity was enhanced in those scaffolds. In vitro studies demonstrated better mesenchymal stem cell adhesion, viability, and osteogenic differentiation on oxidized scaffolds. Those scaffolds also induced angiogenesis, biocompatibility, and biodegradation when implanted subcutaneously in vivo. Hence, the present study demonstrated the usefulness of "oxidized decellularized plant" as bone scaffold for non-load-bearing applications.

Novel Drug Delivery Systems for Loading of Natural Plant Extracts and Their Biomedical Applications

Many types of research have distinctly addressed the efficacy of natural plant metabolites used for human consumption both in cell culture and preclinical animal model systems. However, these in vitro and in vivo effects have not been able to be translated for clinical use because of several factors such as inefficient systemic delivery and bioavailability of promising agents that significantly contribute to this disconnection. Over the past decades, extraordinary advances have been made successfully on the development of novel drug delivery systems for encapsulation of plant active metabolites including organic, inorganic and hybrid nanoparticles. The advanced formulas are confirmed to have extraordinary benefits over conventional and previously used systems in the manner of solubility, bioavailability, toxicity, pharmacological activity, stability, distribution, sustained delivery, and both physical and chemical degradation. The current review highlights the development of novel nanocarrier for plant active compounds, their method of preparation, type of active ingredients, and their biomedical applications.

Layer-by-layer decorated herbal cell compatible scaffolds for bone tissue engineering: A synergistic effect of graphene oxide and Cissus quadrangularis

Among various bone regenerative and repair methods, use of osteoinductive scaffold as bone grafts/substitute has gained wide importance worldwide. To develop such osteoinductive scaffold that is more natural and which spontaneously stimulates osteoblast formation without any differentiation media, we prepared electrospun poly ε-caprolactone scaffold which is further modified by means of layer-by-layer method using Cissus quadrangularis callus culture extract and graphene oxide (PCL-GO-CQ). The modified PCL-GO-CQ scaffold was compared with plain poly ε-caprolactone scaffold and poly ε-caprolactone coated only with graphene oxide. Physical properties, such as roughness, wettability, yield strength and tensile strength, of PCL-GO-CQ scaffold were found to be superior. Also, PCL-GO-CQ scaffold showed more in vitro cell compatibility with enhanced cellular proliferation on its surface. Presence of graphene oxide and Cissus quadrangularis callus in scaffold helped in the differentiation of human umbilical cord Wharton’s jelly-derived mesenchymal stem cells into osteogenic lineage without any differentiation media in less than 20 days. The synergistic effect of Cissus quadrangularis callus extract and graphene oxide in PCL-GO-CQ scaffold enhanced osteoblastic differentiation, osteoconduction and osteoinduction potential of scaffolds making them highly potential in bone regeneration and bone tissue engineering applications.

Comparison of Different Approaches to Surface Functionalization of Biodegradable Polycaprolactone Scaffolds

Due to their good mechanical stability compared to gelatin, collagen or polyethylene glycol nanofibers and slow degradation rate, biodegradable poly-ε-caprolactone (PCL) nanofibers are promising material as scaffolds for bone and soft-tissue engineering. Here, PCL nanofibers were prepared by the electrospinning method and then subjected to surface functionalization aimed at improving their biocompatibility and bioactivity. For surface modification, two approaches were used: (i) COOH-containing polymer was deposited on the PCL surface using atmospheric pressure plasma copolymerization of CO₂ and C₂H₄, and (ii) PCL nanofibers were coated with multifunctional bioactive nanostructured TiCaPCON film by magnetron sputtering of TiC–CaO–Ti₃PO_x target. To evaluate bone regeneration ability in vitro, the surface-modified PCL nanofibers were immersed in simulated body fluid (SBF, 1×) for 21 days. The results obtained indicate different osteoblastic and epithelial cell response depending on the modification method. The TiCaPCON-coated PCL nanofibers exhibited enhanced adhesion and proliferation of MC3T3-E1 cells, promoted the formation of Ca-based mineralized layer in SBF and, therefore, can be considered as promising material for bone tissue regeneration. The PCL–COOH nanofibers demonstrated improved adhesion and proliferation of IAR-2 cells, which shows their high potential for skin reparation and wound dressing.

Improved exposure of bioactive peptides to the outermost surface of the polylactic acid nanofiber scaffold

We recently reported a novel method to modify the polylactic acid (PLLA) nanofiber scaffold with IKVAV peptide/oligo (d-lactic acid) (ODLA) heteroconjugates. However, a part of the IKVAV sequence was not exposed to the outermost surface and therefore, cell adhesion was not optimized. In this study, we evaluated two strategies to improve the exposing efficiency of IKVAV. One strategy introduced a hydrophilic diethylene glycol (diEG) segment between IKVAV and ODLA. In the second method, these modified nanofibers were heated to a given temperature and cooled to room temperature in water. The IKVAV peptides at the outermost surface were quantified by the fluorescein isothiocyanate staining method. After being heated above the PLLA glass transition temperature, the exposing efficiency of the IKVAV sequence on the PLLA/ODLA-diEG-IKVAV nanofiber was three times higher than that on the PLLA/ODLA-IKVAV unheated nanofiber. Moreover, nearly 100% of the PC-12 cells seeded onto the PLLA/ODLA-diEG-IKVAV nanofiber and were well distributed, while only 50% of the PC-12 cells seeded onto the PLLA and PLLA/ODLA-IKVAV nanofibers. These strategies markedly enhanced the exposing efficiency of the bioactive peptides; therefore, their use can be applicable to other nanofiber scaffolds.

Herbally Painted Biofunctional Scaffolds with Improved Osteoinductivity for Bone Tissue Engineering

In the bone tissue engineering composite scaffolds with osteogenic potential are emerging as the new tool. Here, we investigated the graphene (GP), graphene oxide (GO) andCissusquadrangularis(CQ) callus extract for their spontaneous osteoinductive potential. Electrospun poly ε-caprolactone (PCL) sheets were painted with varying combination GP, GO and CQ solutions as ink. The prepared PCL-GO, PCL-GO-CQ, PCL-GP and PCL-GP-CQ scaffolds were characterized for their physical, mechanical and biological properties. Addition of GO, GP, GO-CQ and GP-CQ to PCL enhanced roughness, wettability, Yield strength and tensile strength, biocompatibility .significantly. Presence of GO and CQ in PCL-GO-CQ scaffolds, while GP and CQ in PCL-GP-CQ scaffolds showed synergistic effect on the biocompatibility, Cell attachment,cell proliferation of human umbilical Wharton’s jelly derived mesenchymal stem cells (hUCMSCs) and their differentiation into osteoblasts by 21stday in culture without osteogenic differentiation media or any growth factors. Same is confirmed by the Alizarin red S staining and Von kossa staining. The combination of PCL-GO-CQ scaffold prepared by novel paint method was found to be the most potential in bone tissue engineering.