Pholiota nameko Polysaccharides Promotes Cell Proliferation and Migration and Reduces ROS Content in H2O2-Induced L929 Cells

Insights into the bioactive potential of the Amazonian species Acmella oleracea leaves extract: A focus on wound healing applications

ETHNOPHARMACOLOGICAL RELEVANCE

Acmella oleracea is traditionally used by Amazonian folks to treat skin and mucous wounds, influenza, cough, toothache, bacterial and fungal infections. Its phytoconstituents, such as alkylamides, phenolic compounds, and terpenes, are reported to produce therapeutic effects, which justify the medicinal use of A. oleracea extracts. However, the scientific evidence supporting the application A. oleracea bioactive products for wound treatment of remains unexplored so far.

OBJECTIVE

This work aimed to characterize the phytochemical composition of methanolic extract of A. oleracea leaves (AOM) and to investigate their antioxidant, anti-inflammatory, antimicrobial and healing potential focusing on its application for wound healing.

MATERIAL AND METHODS

The dried leaves from A. oleracea submitted to static maceration in methanol for 40 days. The phytochemical constitution of AOM was analyzed based on the total phenolic dosage method and by UFLC-QTOF-MS analysis. Antioxidant activity was assessed by DPPH and NO scavenging activities, as well as MDA formation, evaluation of ROS levels, and phosphomolybdenum assays. In vitro anti-inflammatory activities were assessed by reduction of NO, IL-6, and TNF-α production and accumulation of LDs in peritoneal macrophages cells. Antimicrobial activity was evaluated by determining MIC and MBC/MFC values against P. aeruginosa, E. coli, S. epidermidis, S. aureus and C. albicans, bacterial killing assay, and biofilm adhesion assessment. In vitro wound healing activity was determined by means of the scratch assay with L929 fibroblasts.

RESULTS

Vanillic acid, quercetin, and seven other alkamides, including spilanthol, were detected in the UFLC-QTOF-MS spectrum of AOM. Regarding the biocompatibility, AOM did not induce cytotoxicity in L929 fibroblasts and murine macrophages. The strong anti-inflammatory activity was evidenced by the fact that AOM reduced the cellular production of inflammatory mediators IL-6, TNF-α, NO, and LDs in macrophages by 100%, 96.66 ± 1.95%, 99.21 ± 3.82%, and 67.51 ± 0.72%, respectively. The antioxidant effects were confirmed, since AOM showed IC50 values of 44.50 ± 4.46 and 127.60 ± 14.42 μg/mL in the DPPH and NO radical inhibition assays, respectively. Additionally, AOM phosphomolybdenium reducing power was 63.56 ± 13.01 (RAA% of quercetin) and 104.01 ± 21.29 (RAA% of rutin). Finally, in the MDA quantification assay, AOM showed 63,69 ± 3.47% of lipid peroxidation inhibition. It was also observed that the production of ROS decreased by 69.03 ± 3.85%. The MIC values of AOM ranged from 1000 to 125 μg/mL. Adhesion of S. aureus, P. Aeruginosa, and mixed biofilms was significantly reduced by 44.71 ± 4.44%, 95.50 ± 6.37 %, and 51.83 ± 1.50%, respectively. AOM also significantly inhibited the growth of S. aureus (77.17 ± 1.50 %) and P. aeruginosa (62.36 ± 1.01%). Furthermore, AOM significantly enhanced the in vitro migration of L929 fibroblasts by 97.86 ± 0.82% compared to the control (P < 0.05).

CONCLUSIONS

This study is the first to report total antioxidant capacity and intracellular LD reduction by AOM. The results clearly demonstrated that AOM exerts potent anti-inflammatory, antioxidant, antimicrobial, and wound healing effects, encouraging its further investigation and promising application in wound treatment.

The Anti-Inflammatory Effects and Mechanism of the Submerged Culture of Ophiocordyceps sinensis and Its Possible Active Compounds

The pharmacological effects of the fruiting body of Ophiocordyceps sinensis (O. sinensis) such as antioxidant, anti-virus, and immunomodulatory activities have already been described, whereas the anti-inflammatory effects and active components of the submerged culture of O. sinesis (SCOS) still need to be further verified. This study aimed to investigate the active compounds in the fermented liquid (FLOS), hot water (WEOS), and 50-95% (EEOS-50, EEOS-95) ethanol extracts of SCOS and their anti-inflammatory effects and potential mechanisms in lipopolysaccharide (LPS)-stimulated microglial BV2 cells. The results demonstrated that all of the SCOS extracts could inhibit NO production in BV2 cells. EEOS-95 exhibited the strongest inhibitory effects (71% inhibitory ability at 500 µg/mL), and its ergosterol, γ-aminobutyric acid (GABA), total phenolic, and total flavonoid contents were significantly higher than those of the other extracts (18.60, 18.60, 2.28, and 2.14 mg/g, p < 0.05, respectively). EEOS-95 also has a strong inhibitory ability against IL-6, IL-1β, and TNF-α with an IC50 of 617, 277, and 507 µg/mL, respectively, which is higher than that of 1 mM melatonin. The anti-inflammatory mechanism of EEOS-95 seems to be associated with the up-regulation of PPAR-γ/Nrf-2/HO-1 antioxidant-related expression and the down-regulation of NF-κB/COX-2/iNOS pro-inflammatory expression signaling. In summary, we demonstrated that EEOS-95 exhibits neuroinflammation-mediated neurodegenerative disorder activities in LPS-induced inflammation in brain microglial cells.

Nanosized Complexes of the Proteolytic Enzyme Serratiopeptidase with Cationic Block Copolymer Micelles Enhance the Proliferation and Migration of Human Cells

In this study, we describe the preparation of the cationic block copolymer nanocarriers of the proteolytic enzyme serratiopeptidase (SER). Firstly, an amphiphilic poly(2-(dimethylamino)ethyl methacrylate)-b-poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA9-b-PCL35-b-PDMAEMA9) triblock copolymer was synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization. Then, cationic micellar nanocarriers consisting of a PCL hydrophobic core and a PDMAEMA hydrophilic shell were formed by the solvent evaporation method. SER was loaded into the polymeric micelles by electrostatic interaction between the positively charged micellar shell and the negatively charged enzyme molecules. The particle size, zeta potential, and colloid stability of complexes as a function of SER concentration were investigated by dynamic and electrophoretic light scattering. It was found that SER retained its proteolytic activity after immobilization in polymeric carriers. Moreover, the complexes have a concentration-dependent enhancing effect on the proliferation and migration of human keratinocyte HaCaT and gingival fibroblast HGF cells.

Incorporation of Resveratrol-Hydroxypropyl-β-Cyclodextrin Complexes into Hydrogel Formulation for Wound Treatment

Resveratrol could be applied in wound healing therapies because of its antioxidant, anti-inflammatory and antibacterial effects. However, the main limitation of resveratrol is its low aqueous solubility. In this study, resveratrol was included in hydroxypropyl-β-cyclodextrin complexes and further formulated in Pluronic F-127 hydrogels for wound treatment therapy. IR-spectroscopy and XRD analysis confirmed the successful incorporation of resveratrol into complexes. The wound-healing ability of these complexes was estimated by a scratch assay on fibroblasts, which showed a tendency for improvement of the effect of resveratrol after complexation. The antimicrobial activity of resveratrol in aqueous dispersion and in the complexes was evaluated on methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Candida albicans strains. The results revealed a twofold decrease in the MIC and stronger inhibition of the metabolic activity of MRSA after treatment with resveratrol in the complexes compared to the suspended drug. Furthermore, the complexes were included in Pluronic hydrogel, which provided efficient drug release and appropriate viscoelastic properties. The formulated hydrogel showed excellent biocompatibility which was confirmed via skin irritation test on rabbits. In conclusion, Pluronic hydrogel containing resveratrol included in hydroxypropyl-β-cyclodextrin complexes is a promising topical formulation for further studies directed at wound therapy.

The function and application of edible fungal polysaccharides

Edible fungi, commonly known as mushrooms, are precious medicinal and edible homologous gifts from nature to us. Edible fungal polysaccharides (EFPs) are a variety of bioactive macromolecular which isolated from fruiting bodies, mycelia or fermentation broths of edible or medicinal fungus. Increasing researches have confirmed that EFPs possess multiple biological activities both in vitro and in vivo settings, including antioxidant, antiviral, anti-inflammatory, immunomodulatory, anti-tumor, hypoglycemic, hypolipidemic, and regulating intestinal flora activities. As a result, they have emerged as a prominent focus in the healthcare, pharmaceutical, and cosmetic industries. Fungal EFPs have safe, non-toxic, biodegradable, and biocompatible properties with low immunogenicity, bioadhesion ability, and antibacterial activities, presenting diverse potential applications in the food industries, cosmetic, biomedical, packaging, and new materials. Moreover, varying raw materials, extraction, purification, chemical modification methods, and culture conditions can result in variances in the structure and biological activities of EFPs. The purpose of this review is to provide comprehensively and systematically organized information on the structure, modification, biological activities, and potential applications of EFPs to support their therapeutic effects and health functions. This review provides new insights and a theoretical basis for prospective investigations and advancements in EFPs in fields such as medicine, food, and new materials.

In-vivo and in-vitro wound healing and tissue repair effect of Trametes versicolor polysaccharide extract

Regarding different medical benefits of fungi, using the medical mushroom extracts as wound-healing agents is gaining popularity. This study, evaluated the wound healing characteristics of Trametes versicolor. Anti-oxidant activity addressed by employing the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay resulting 53.7% inhibitory effect. Besides, for anti-microbial ability determination, the MIC (Minimum Inhibitory Concentration) of extract measured which Escherichia coli growth was inhibited at 1.1 mg/ml, and Staphylococcus aureus did not grow at 4.38 mg/ml of extract. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method indicated dose dependence of the extract with 63 ± 3% and 28 ± 3% viability at 1250 μg/ml and 156.25 μg/ml of extract, which higher concentration caused higher cell viability. The outcome of gene expression analysis determined that overall expression of FGF2 (Fibroblast Growth Factor 2), IL-1β (Interleukin-1β), and TGF-β1 (Transforming Growth Factor-β1) was 4 times higher at 48 h than at 24 h in treated cells, suggesting a stimulating effect on cell growth. An in-vivo animal model suggested enhanced wound healing process after treatment with 0.01 g of extract. Furthermore, the number of fibroblasts, epidermal thickness, and collagen fiber was respectively 2, 3, and threefold higher in treated mice when compared to untreated mice. The treated wounds of mice showed 100% and 60% of untreated mice of healing within 14 days. The results of this research show promise for the fungus-based wound healing treatments, which may help with tissue regeneration and the healing of cutaneous wounds.

Preparation and characterization of a jelly fig (Ficus awkeotsang Makino) polysaccharide-based bioactive 3D scaffold for improved vascularization and skin tissue engineering applications

Jelly fig polysaccharides (JFP) were extracted from Ficus awkeotsang Makino achenes. The yield of JFP was approximately 10-15 %. FT-IR spectrum of the extracted JFP confirmed that it was made of low methoxyl pectin (LMP). 3D scaffolds of JFP (JFP scaffold) were fabricated using ionic crosslinking of 2 % (w/v) JFP solution with Ca2+ ions and freeze-drying. The JFP scaffold showed 73.46 ± 1.97 % porosity and a 12-fold swelling capacity. The porous morphology was also observed in SEM micrographs. JFP scaffolds were completely degraded in 14 days when incubated in 1 mg/mL lysozyme solution, compared to the 50 % degradation observed in PBS alone. The antioxidant activity of the JFP and JFP scaffold was approximately 40 %. The hemolytic assay of the JFP scaffold showed <5 % (3.0 ± 0.4) RBC lysis. The cytocompatibility of the JFP scaffold was evaluated using L929 mouse fibroblasts and human dermal fibroblasts (HDF). The in vitro studies using L929 cells showed that the JFP scaffold is cytocompatible. HDF cells cultured in the presence of JFP scaffolds show a higher fold cell viability, proliferation, and migration. Collagen expression and deposition were also studied, and no significant changes occurred with JFP scaffold treatment. In vivo CAM assay showed an increase in the number and thickness of blood vessels by 1.185-fold and 1.19-fold, respectively. These results confirm the angiogenic property of the JFP scaffold. These biocompatible and bioactive properties of the JFP scaffold could be beneficial for tissue engineering and regenerative medicine applications.

Pterostilbene accelerates wound healing response in diabetic mice through Nrf2 regulation

Pterostilbene (PTS), known for its diverse beneficial effects via Nuclear factor erythroid-2 related factor (Nrf2) activation, holds potential for Diabetic Foot Ulcer (DFU) treatment. However, PTS-mediated Nrf2 regulation in diabetic wounds has yet to be elucidated. We used IC21 macrophage-conditioned media to simulate complex events that can influence the fibroblast phenotype using L929 cells during the wound healing process under a hyperglycemic microenvironment. We found that PTS attenuated fibroblast migration and alpha-smooth muscle actin (α-SMA) levels and hypoxia-inducible factor- 1 alpha (HIF1α). Furthermore, we demonstrated that wounds in diabetic mice characterized by impaired wound closure in a heightened inflammatory milieu, such as the NOD-like receptor P3 (NLRP3) and intercellular adhesion molecule 1 (ICAM1), and deficient Nrf2 response accompanying lowered Akt signaling and heme oxygenase1 (HO1) expression along with the impaired macrophage M2 marker CD206 expression, was rescued by administration of PTS. Such an elicited response was also compared favorably with the standard treatment using Regranex, a commercially available topical formulation for treating DFUs. Our findings suggest that PTS regulates Nrf2 in diabetic wounds, triggering a pro-wound healing response mediated by macrophages. This insight holds the potential for developing targeted therapies to heal chronic wounds, including DFUs.

Surface-mediated high antioxidant and anti-inflammatory effects of astaxanthin-loaded ultrathin graphene oxide film that inhibits the overproduction of intracellular reactive oxygen species

Background

Astaxanthin (AST) is known as a powerful antioxidant that affects the removal of active oxygen and inhibits the production of lipid peroxide caused by ultraviolet light. However, it is easily decomposed by heat or light during production and storage because of the unsaturated compound nature with a structural double bond. The activity of AST can be reduced and lose its antioxidant capability. Graphene oxide (GO) is an ultrathin nanomaterial produced by oxidizing layered graphite. The chemical combination of AST with GO can improve the dispersion properties to maintain structural stability and antioxidant activity because of the tightly bonded functionalized GO surface.

Methods

Layered GO films were used as nanocarriers for the AST molecule, which was produced via flow-enabled self-assembly and subsequent controlled solution deposition of RGD peptide and AST molecules. Synthesis of the GO-AST complex was also carried out for the optimized concentration. The characterization of prepared materials was analyzed through transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FT-IR), atomic force microscope (AFM), and Raman spectroscopy. Antioxidant activity was tested by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2.2-diphenyl-1-picrylhydrazyl (DPPH) assays. The antibacterial effect and antioxidant effects were monitored for the ultrathin GO/RGD/AST Film. Further, reactive oxygen species (ROS) assay was used to evaluate the anti-inflammatory effects on L-929 fibroblasts.

Results

Cotreatment of GO-AST solution demonstrated a high antioxidant combined effect with a high ABTS and DPPH radicals scavenging activity. The GO/RGD/AST film was produced by the self-assembly process exhibited excellent antibacterial effects based on physicochemical damage against E. coli and S. aureus. In addition, the GO/RGD/AST film inhibited H₂O₂-induced intracellular ROS, suppressed the toxicity of lipopolysaccharide (LPS)-induced cells, and restored it, thereby exhibiting strong antioxidant and anti-inflammatory effects.

Conclusion

As GO nanocarrier-assisted AST exerted promising antioxidant and antibacterial reactions, presented a new concept to expand basic research into the field of tissue engineering.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40824-022-00276-4.

Pholiota nameko Polysaccharides Protect against Ultraviolet A-Induced Photoaging by Regulating Matrix Metalloproteinases in Human Dermal Fibroblasts

Ultraviolet-A (UVA) exposure is a major cause of skin aging and can induce oxidative damage and accelerate skin wrinkling. Many natural polysaccharides exhibit a UV protective effect. In research on Pholiota nameko polysaccharides (PNPs), a natural macromolecular polysaccharide (4.4–333.487 kDa), studies have shown that PNPs can significantly decrease elastase activity to protect against UVA-induced aging in Hs68 human dermal fibroblasts. Cellular experiments in the present study indicated that PNPs can protect against UVA-induced oxidative damage in Hs68 cells by inhibiting the production of reactive oxygen species. Furthermore, PNPs significantly attenuated UVA-induced cell aging by decreasing the protein expression of matrix metalloproteinase 1, 3, and 9. Pretreatment of Hs68 cells with PNP-40, PNP-60, and PNP-80 before UVA irradiation increased protein expression of tissue inhibitor metalloproteinase 1 by 41%, 42%, and 56% relative to untreated cells. In conclusion, this study demonstrates that PNPs are a natural resource with potentially beneficial effects in protecting against UVA-induced skin aging.

Effect of Pholiota nameko Polysaccharides Inhibiting Methylglyoxal-Induced Glycation Damage In Vitro

Advanced glycation end products (AGEs) can induce oxidative stress and inflammation. AGEs are major risk factors for the development of many aging-related diseases, such as cancer and diabetes. In this study, Pholiota nameko polysaccharides (PNPs) were prepared from water extract of P. nameko via graded alcohol precipitation (40%, 60%, and 80% v/v). We explored the in vitro antiglycation ability of the PNPs and inhibition of methylglyoxal (MG)-induced Hs68 cell damage. In a bovine serum albumin (BSA) glycation system, PNPs significantly inhibited the formation of Amadori products. Fluorescence spectrophotometry revealed that the PNPs trapped MG and reduced MG-induced changes in functional groups (carbonyl and ε-NH₂) in the BSA. Pretreating Hs68 cells with PNPs enhanced the cell survival rate and protected against MG-induced cell damage. This was due to decreased intracellular ROS content. PNPs thus mitigate skin cell damage and oxidative stress resulting from glycation stress, making them a potential raw material for antiaging-related skincare products.

Therapeutic candidates for keloid scars identified by qualitative review of scratch assay research for wound healing

The scratch assay is an in vitro technique used to analyze cell migration, proliferation, and cell-to-cell interaction. In the assay, cells are grown to confluence and then ‘scratched’ with a sterile instrument. For the cells in the leading edge, the resulting polarity induces migration and proliferation in attempt to ‘heal’ the modeled wound. Keloid scars are known to have an accelerated wound closure phenotype in the scratch assay, representing an overactivation of wound healing. We performed a qualitative review of the recent literature searching for inhibitors of scratch assay activity that were already available in topical formulations under the hypothesis that such compounds may offer therapeutic potential in keloid treatment. Although several shortcomings in the scratch assay literature were identified, caffeine and allicin successfully inhibited the scratch assay closure and inflammatory abnormalities in the commercially available keloid fibroblast cell line. Caffeine and allicin also impacted ATP production in keloid cells, most notably with inhibition of non-mitochondrial oxygen consumption. The traditional Chinese medicine, shikonin, was also successful in inhibiting scratch closure but displayed less dramatic impacts on metabolism. Together, our results partially summarize the strengths and limitations of current scratch assay literature and suggest clinical assessment of the therapeutic potential for these identified compounds against keloid scars may be warranted.

Fabrication of In Situ Layered Hydrogel Scaffold for the Co-delivery of PGDF-BB/Chlorhexidine to Regulate Proinflammatory Cytokines, Growth Factors, and MMP-9 in a Diabetic Skin Defect Albino Rat Model

Diabetes mellitus (DM)-associated impairments in wound healing include prolonged inflammation, the overexpression of matrix metalloproteases (MMPs), and low levels of growth factors at the wound site. To this end, a layer-by-layer scaffold (S_L-B-L) made of cross-linked silk fibroin and hyaluronic acid is developed to deliver chlorhexidine, an antimicrobial agent and an MMP-9 inhibitor, along with the PDGF-BB protein. S_L-B-L exhibited highly porous morphology. Diabetic rats treated with S_L-B-L demonstrated an early wound closure, a fully reconstructed epithelial layer by 14 days, and reduced levels of IL-6, TNF-α, TGF-β1, and MMP-9. Interestingly, S_L-B-L treatment increased angiogenesis, the bioavailability of collagen, DNA content, and VEGF-A levels. Furthermore, enhanced keratinocyte-fibroblast interaction along with ordered collagen deposition was observed in S_L-B-L-treated rats. Most interestingly, when compared with a clinically used scaffold SEESKIN+, S_L-B-L outperformed in promoting wound healing in a diabetic rat model by regulating the inflammation while delivering growth factor and the MMP-9 inhibitor.

PDT-Enhanced Ferroptosis by a Polymer Nanoparticle with pH-Activated Singlet Oxygen Generation and Superb Biocompatibility for Cancer Therapy

In this study, we reported a nanocomplex (PAF) of PEGylated polygalacturonic acid, 5,10,15,20-tetrakis (4-aminophenyl) porphyrin (TAPP), and Fe³⁺ for photodynamic therapy (PDT)-enhanced ferroptosis in cancer treatment. PAF exhibited a size of 135 nm and a TAPP and Fe³⁺ loading content of 6.99 and 0.77%, respectively. The singlet oxygen (¹O₂) generation capacity of TAPP can be activated and significantly enhanced at acidic pH (4.5-5.0). Besides, the enhanced near-infrared absorption of TAPP at acidic pH enabled a further increase in ¹O₂ generation capability by a near-infrared laser (760 nm). The polysaccharide-based polymer carrier offers excellent biocompatibility, and PAF displayed a proliferative effect in both normal (L929) and cancer (B16) cells. However, upon light irradiation, PAF exhibited high toxicity to B16 melanoma cells by intracellular reactive oxygen species elevation, glutathione depletion, and lipid peroxidation. PAF displayed a much better anticancer effect than the nanocomplex containing Fe³⁺ or TAPP alone, indicating the PDT-enhanced ferroptosis in PAF. This study suggested that PDT-enhanced ferroptosis could be a facile and robust strategy of nanotherapeutics with high potency, tumor selectivity, and excellent biocompatibility.