Interaction of Gold Nanorods with Human Dermal Fibroblasts: Cytotoxicity, Cellular Uptake, and Wound Healing

Synergistic effect of gold nanorods coated with type I collagen and LED irradiation on wound healing in human skin fibroblast cells

Delayed wound healing poses a significant risk to human health, especially when wounds are infected by pathogens. Therefore, the development of effective methods for accelerating wound healing is important. This study investigated the synergistic effect of gold nanorods (GNRs) coated with type I collagen (GNRs@C) combined with light-emitting diode (LED) irradiation on wound healing in scratched human skin fibroblast (HSF) cells. Scratched HSF cells were treated with 3 μg mL-1 GNRs@C, followed by LED irradiation. This combined treatment significantly enhanced cell proliferation, increasing from the control cell base line (scratched HSF cells without any treatment) to 104.08 ± 2.96% and 107.82 ± 3.25% after 24 and 48 h of incubation, respectively. GNRs@C demonstrated superior cellular uptake compared to uncoated GNRs. Notably, complete closure of scratched HSF cells was observed in scratched HSF cells treated with GNRs@C with LED irradiation and then incubated for 40 h. Additionally, the treatment significantly reduced interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) levels, while upregulating key growth factors, including vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). These findings demonstrate the wound healing potential of GNRs@C combined with LED irradiation.

Strontium nitrate-dopped zinc oxide-loaded alginate gels with gentamicin for improved wound healing

Wound dressing development is an area of active research. Traditional dressings lack antibacterial activity, biocompatibility, and tissue regeneration. Alginate is a heavily investigated polymer employed as wound dressings and can be combined with a wide range of additives. Herein, we report the preparation of alginate gel using the crosslinking technique as potential wound dressing, with insight investigation of the influence of employing single, two, or three cross-linkers: Strontium (Sr), zinc oxide (ZnO), and gentamicin sulfate. Rheology was used to confirm the gel's preparation, where the samples' viscosity curves show decreased viscosity with increased shear rate, indicating pseudoplastic flow. The linear viscoelastic region shows constant G' and G" within the sample structure. In this study, we used three gels with different mixtures of ingredients: Gels A, B, and C contain sodium alginate (1% w/v) and 0.5 mL of Sr nitrate (4% w/v). However, Gels B and C contain 0.25 mL of ZnO (0.5% w/v). Gel C also includes 0.1 mL of gentamicin (1% w/v). The study examined the effectiveness of Gel A, B, and C on wound healing, calculating the reduction of wound area after seven, 14, and 20 days of a single topical treatment. Gel A, B, and C significantly reduced wound area, while Gel B and C showed a significant reduction. The zone of inhibition was used to detect the gels' efficacy against microorganisms. The study found zinc deposition in the liver and bone, with Gel B and C showing higher levels. The study also found significant overexpression of MIP α and MIP β in tissues and downregulation of CCL2, IL8, and TGF β, explaining wound healing with minimal scar formation.

Gold nanorods as biocompatible nano-agents for the enhanced photothermal therapy in skin disorders

Rod-shaped gold nanomaterials, known as gold nanorods (GNRs), may undergo specific surface modification, because of their straightforward surface chemistry. This feature makes them appropriate for use as functional and biocompatible nano-formulations. By optimizing the absorption of longitudinally localized surface plasmon resonance in the near-infrared region, which corresponds to the near-infrared bio-tissue window, GNRs with appropriate modifications may improve the results of photothermal treatment (PTT). In dermatology, potential noninvasive uses of GNRs to enhance wound healing, manage infections, combat cutaneous malignancies, and remodel skin tissues via PTT have attracted research attention in recent years. The review discussed the basic properties of GNRs, such as their shape, size, optical performance, photothermal efficiency, and metabolism. Then, the disadvantages of using these particles in photodynamic therapy are highlighted. Next, biological applications of GNRs-based PTT are explored in detail. Finally, the limitations and future perspectives of this research are addressed, providing a comprehensive perspective on the potential GNRs with PTT.

Evaluating the Effects of BSA-Coated Gold Nanorods on Cell Migration Potential and Inflammatory Mediators in Human Dermal Fibroblasts

Albumin-coated gold nanoparticles display potential biomedical applications, including cancer research, infection treatment, and wound healing; however, elucidating their interaction with normal cells remains an area with limited exploration. In this study, gold nanorods (GNR) were prepared and coated with bovine serum albumin (BSA) to produce GNR-BSA. The functionalized nanoparticles were characterized based on their optical absorption spectra, morphology, surface charge, and quantity of attached protein. The interaction between GNR-BSA and BSA with normal cells was investigated using human dermal fibroblasts. The cytotoxicity test indicated cell viability between ~63-95% for GNR-BSA over concentrations from 30.0 to 0.47 μg/mL and ~85-98% for BSA over concentrations from 4.0 to 0.0625 mg/mL. The impact of the GNR-BSA and BSA on cell migration potential and wound healing was assessed using scratch assay, and the modulation of cytokine release was explored by quantifying a panel of cytokines using Multiplex technology. The results indicated that GNR-BSA, at 10 μg/mL, delayed the cell migration and wound healing 24 h post-treatment compared to the BSA or the control group with an average wound closure percentage of 6% and 16% at 6 and 24 h post-treatment, respectively. Multiplex analysis revealed that while GNR-BSA reduced the release of the pro-inflammatory marker IL-12 from the activated fibroblasts 24 h post-treatment, they significantly reduced the release of IL-8 (p < 0.001), and CCL2 (p < 0.01), which are crucial for the inflammation response, cell adhesion, proliferation, migration, and angiogenesis. Although GNR-BSA exhibited relatively high cell viability towards human dermal fibroblasts and promising therapeutic applications, toxicity aspects related to cell motility and migration must be considered.

Investigating Inflammatory Markers in Wound Healing: Understanding Implications and Identifying Artifacts

Understanding the complex interplay of pro-inflammatory and anti-inflammatory cytokines is crucial in the field of wound healing, as it holds the key to developing effective therapeutics. In the initial stages of wound healing, pro-inflammatory cytokines like IL-1β, IL-6, TNF-α, and various chemokines play vital roles in recruiting cells for debris clearance and the recruitment of growth factors. Careful regulation and timely resolution of this early inflammation are essential for optimal wound repair. As the healing process progresses, anti-inflammatory proteins such as IL-10 and IL-4 become instrumental in facilitating the transition to later stages where pro-inflammatory cytokines promote angiogenesis and wound remodeling. This Perspective underscores the complexity of inflammatory cytokines in wound healing research and emphasizes the need for comprehensive and unbiased methodologies in their evaluation. For robust and reliable results in wound-healing research, a more holistic approach is necessary-one that considers the roles, interactions, and timing of biological molecules, alongside careful sampling and evaluation strategies.

Biological Performance of Primary Dental Pulp Stem Cells Treated with Gold Nanoparticles

Gold nanoparticles (AuNPs) are one of the most stable nanoparticles that have been prevalently used as examples for biological and biomedical applications. Herein, we evaluate the effect of AuNPs on the biological processes of dental pulp stem cells derived from exfoliated deciduous teeth (SHED). Two different shapes of PEGylated AuNPs, rods (AuNR-PEG) and spheres (AuNS-PEG), were prepared and characterized. SHED cells were treated with different concentrations of AuNR-PEG and AuNS-PEG to determine their effect on the stemness profile of stem cells (SCs), proliferation, cytotoxicity, cellular uptake, and reactive oxygen species (ROS), for cells cultured in media containing-fetal bovine serum (FBS) and serum-free media (SFM). Our results showed that both nanoparticle shapes maintained the expression profile of MSC surface markers. Moreover, AuNS-PEG showed a stimulatory effect on the proliferation rate and lower toxicity on SHED, compared to AuNR-PEG. Higher concentrations of 0.5-0.125 nM of AuNR-PEG have been demonstrated to cause more toxicity in cells. Additionally, cells treated with AuNPs and cultured in FBS showed a higher proliferative rate and lower toxicity when compared to the SFM. For cellular uptake, both AuNS-PEG and AuNR-PEG were uptaken by treated cells efficiently. However, cells cultured in SFM media showed a higher percentage of cellular uptake. For ROS, AuNR-PEG showed a significant reduction in ROS at lower concentrations (<0.03 nM), while AuNS-PEG did not show any significant difference compared to the control untreated cells. Thus, our results give evidence about the optimum concentration and shape of AuNPs that can be used for the differentiation of stem cells into specific cell lineages in tissue engineering and regenerative medicine.

Gold Nanorods-Based Photothermal Therapy: Interactions Between Biostructure, Nanomaterial, and Near-Infrared Irradiation

Gold nanorods (AuNRs) are ideal inorganic nanophotothermal agents with unique characteristics, including local surface plasmon resonance effects, easy scale preparation and functional modification, and good biocompatibility. This review summarizes several recent advances in AuNRs-based photothermal therapy (PTT) research. Functionalized AuNRs photothermal agents have optimized biocompatibility and targeting properties. The multifunctional AuNRs nanoplatform composite structure meets the requirements for synergistic effects of PTT, photoacoustic imaging, and other therapeutic methods. Photothermal therapy with AuNRs (AuNRs-PTT) is widely used to treat tumors and inflammatory diseases; its tumor-targeting, tumor metastasis inhibition, and photothermal tumor ablation abilities have remarkable curative effects. An in-depth study of AuNRs in living systems and the interactions between biological structure, nanomaterial, and near-infrared irradiation could lay the foundation for further clinical research and the broad application of AuNRs in PTT.

Evaluating Antimicrobial Activity and Wound Healing Effect of Rod-Shaped Nanoparticles

Presently, the nanotechnology approach has gained a great concern in the media of drug delivery. Gold nanoparticles (Au-NPs) specially having a non-spherical structure, such as gold nanorods (GNR), are attracting much interest as antibacterial agent and many other medical fields. The aim of the current investigation was to characterize Au-NPs and investigate their antimicrobial and wound healing efficacy in diabetic animals.

MATERIAL AND METHODS

Au-NPs were characterized using a UV-Vis spectrophotometer, estimating their particle size, polydispersity (PDI), and assessing their morphological characters. Further, Au-NPs were estimated for their antibacterial and antifungal behavior. Ultimately, in vivo activity of Au-NPs was evaluated against excision wound healing in STZ-induced diabetic animals.

RESULTS

Au-NPs were found to show maximum absorption at 520 nm. They exhibited a particle size of 82.57 nm with a PDI value of 0.323. Additionally, they exhibited good antimicrobial activity against different bacterial strains. Topical application of Au-NPs caused a significantly increased percentage of wound area reduction, lesser time needed for epithelialization, and augmented hydroxyproline, collagen, and hexosamine levels demonstrating enhanced healing processes. Furthermore, Au-NPs displayed a significant intensification in angiogenesis-related factors (HIF-1α, TGF-β1, and VEGF), and antioxidant enzymes activities (CAT, SOD, GPx) as well as mitigated inflammatory mediators IL-6, IL-1β, TNF-α, and NF-κB) and lipid peroxidation (MDA).

CONCLUSION

Au-NPs exhibited proper particle size, and rod-shaped particles, with efficient antimicrobial behavior against different bacterial strains. Furthermore, Au-NPs demonstrated a promising wound healing activity in STZ-induced diabetic animals.

In Vivo Evaluation of Multifunctional Gold Nanorods for Boron Neutron Capture and Photothermal Therapies

The incidence and mortality of cancer demand more innovative approaches and combination therapies to increase treatment efficacy and decrease off-target side effects. We describe a boron-rich nanoparticle composite with potential applications in both boron neutron capture therapy (BNCT) and photothermal therapy (PTT). Our strategy is based on gold nanorods (AuNRs) stabilized with polyethylene glycol and functionalized with the water-soluble complex cobalt bis(dicarbollide) ([3,3'-Co(1,2-C₂B₉H₁₁)₂]^-), commonly known as COSAN. Radiolabeling with the positron emitter copper-64 (⁶⁴Cu) enabled in vivo tracking using positron emission tomography imaging. ⁶⁴Cu-labeled multifunctionalized AuNRs proved to be radiochemically stable and capable of being accumulated in the tumor after intravenous administration in a mouse xenograft model of gastrointestinal cancer. The resulting multifunctional AuNRs showed high biocompatibility and the capacity to induce local heating under external stimulation and trigger cell death in heterogeneous cancer spheroids as well as the capacity to decrease cell viability under neutron irradiation in cancer cells. These results position our nanoconjugates as suitable candidates for combined BNCT/PTT therapies.

Cellular Uptake Pathways of Nanoparticles: Process of Endocytosis and Factors Affecting Their Fate

BACKGROUND

Efficient and controlled internalization of NPs into the cells depends on their physicochemical properties and dynamics of the plasma membrane. NPs-cell interaction is a complex process that decides the fate of NPs internalization through different endocytosis pathways.

OBJECTIVE

The aim of this review is to highlight the physicochemical properties of synthesized nanoparticles (NPs) and their interaction with the cellular-dynamics and pathways like phagocytosis, pinocytosis, macropinocytosis, clathrin, and caveolae-mediated endocytosis and the involvement of effector proteins domain such as clathrin, AP2, caveolin, Arf6, Cdc42, dynamin and cell surface receptors during the endocytosis process of NPs.

METHOD

An electronic search was performed to explore the focused reviews and research articles on types of endocytosis and physicochemical properties of nanoparticles and their impact on cellular internalizations. The search was limited to peer-reviewed journals in the PubMed database.

RESULTS

This article discusses in detail how different types of NPs and their physicochemical properties such as size, shape, aspect ratio, surface charge, hydrophobicity, elasticity, stiffness, corona formation, surface functionalization changes the pattern of endocytosis in the presence of different pharmacological blockers. Some external forces like a magnetic field, electric field, and ultrasound exploit the cell membrane dynamics to permeabilize them for efficient internalization with respect to fundamental principles of membrane bending and pore formation.

CONCLUSION

This review will be useful to attract and guide the audience to understand the endocytosis mechanism and their pattern with respect to physicochemical properties of NPs to improve their efficacy and targeting to achieve the impactful outcome in drug-delivery and theranostics applications.

Gold nanoparticles show potential in vitro antiviral and anticancer activity

AIMS

Gold nanoparticles (AuNPs) have been attracted interests in the various areas of clinical therapeutics. In this study, we investigated the anticancer and antiviral potential activity of AuNPs against influenza A virus and human glioblastoma (GMB) U-87 and U-251 cell lines.

MAIN METHODS

Gold nanoparticles (AuNPs) were synthesized by citrate reduction method. Then, ultraviolet-visible spectrophotometry (UV-vis spectra) and electron microscopy analysis confirmed the type, size (mean diameter of 17 nm) and distribution of the particles. The AuNPs in vitro antiviral and anticancer effects was evaluated by hemagglutination inhibition (HAI), tissue culture infectious dose 50 (TCID₅₀), real-time PCR, MTT, flow cytometry, and scratch assays.

KEY FINDINGS

The AuNPs were synthesized in spherical with a mean diameter of 17 ± 2 nm and an absorbance peak at 520 nm. The AuNPs were well tolerable by MDCK cells at concentrations up to 0.5μg/ml and they significantly inhibited the hemagglutination and virus infectivity, particularly when added pre- or during virus infection. Furthermore, anticancer results indicated that AuNPs treatment caused the marked induction of apoptosis and reduced growth and migration capability of U-87 and U-251 cell lines in a time-dependent manner.

SIGNIFICANCE

The present results suggest that AuNPs provide promising antiviral and anticancer approaches. Further research is needed to fully elucidate the mode of antiviral and anticancer action of AuNPs against influenza virus infection and human glioblastoma cell lines.

Improvement of Gold Nanorods in Photothermal Therapy: Recent Progress and Perspective

Cancer is a life-threatening disease, and there is a significant need for novel technologies to treat cancer with an effective outcome and low toxicity. Photothermal therapy (PTT) is a noninvasive therapeutic tool that transports nanomaterials into tumors, absorbing light energy and converting it into heat, thus killing tumor cells. Gold nanorods (GNRs) have attracted widespread attention in recent years due to their unique optical and electronic properties and potential applications in biological imaging, molecular detection, and drug delivery, especially in the PTT of cancer and other diseases. This review summarizes the recent progress in the synthesis methods and surface functionalization of GNRs for PTT. The current major synthetic methods of GNRs and recently improved measures to reduce toxicity, increase yield, and control particle size and shape are first introduced, followed by various surface functionalization approaches to construct a controlled drug release system, increase cell uptake, and improve pharmacokinetics and tumor-targeting effect, thus enhancing the photothermal effect of killing the tumor. Finally, a brief outlook for the future development of GNRs modification and functionalization in PTT is proposed.

Modulation of the triggered apoptosis by nano emodin transfersome-mediated sonodynamic therapy on head and neck squamous cell carcinoma cell lines

BACKGROUND

Non-invasive sonodynamic therapy (SDT) is a new treatment modality that uses low-intensity ultrasound to activate a non-toxic sensitizing chemical agent for cancer therapy in a site-directed manner. This study aimed to investigate the anti-cancer effects of ultrasound combined with nano emodin transfersome (NET) on head and neck squamous cell carcinoma (HNSCC) cell lines.

MATERIALS AND METHODS

A transfersome form of nano emodin as a novel sono-responsive nanomaterial was synthesized to enhance the accumulation and penetration of nanoparticles. iIn vitro experiments including hemolytic activity, cell proliferation, intracellular reactive oxygen species (ROS) generation, apoptosis induction, DNA fragmentation, and mRNA expressions of caspase 3 and 9 were conducted to explore the anti-cancer effects of NET-SDT on FaDu and CAL-27 cell lines.

RESULTS

Characterization tests showed the round and uniform morphology of NET with transfersome structure, resulting in a high drug-loading content and encapsulation efficiency. No significant hemolytic activity was observed (P > 0.05). Cytotoxicity gradually increased with increasing concentrations of NET, so that 10 × 10^-4 g/L of NET plus 5 min ultrasound irradiation at a frequency of 1 MHz and ultrasonic intensity of 2 W/cm² effectively killed 98.2 % and 97.3 % of FaDu and CAL-27 cell lines, respectively (P < 0.05). We found that ROS generation in NET-SDT was dose-dependent and the triggered apoptosis and caspase-3/9 gene expression levels were significantly enhanced as the concentration of NET increased (P < 0.05). No significant difference was found in the rate of apoptosis induction and gene expression between two cell lines.

CONCLUSIONS

Our data demonstrated that SDT with NET as a sonosensitizer can induce apoptosis and significantly decrease cell viability of HNSCC cell lines, which represents the role of NET-SDT as a potent anti-cancer modality.

Dual-action of thermoresponsive gels containing DsiRNA-loaded gold nanoparticles for diabetic wound therapy: Characterization, in vitro safety and healing efficacy

Diabetic wounds are difficult to treat due to multiple causes, including reduced blood flow and bacterial infections. Reduced blood flow is associated with overexpression of prostaglandin transporter (PGT) gene, induced by hyperglycaemia which causing poor vascularization and healing of the wound. Recently, gold nanoparticles (AuNPs) have been biosynthesized using cold and hot sclerotium of Lignosus rhinocerotis extracts (CLRE and HLRE, respectively) and capped with chitosan (CS) to produce biocompatible antibacterial nanocomposites. The AuNPs have shown to produce biostatic effects against selected gram positive and negative bacteria. Therefore, in this study, a dual therapy for diabetic wound consisting Dicer subtract small interfering RNA (DsiRNA) and AuNPs was developed to improve vascularization by inhibiting PGT gene expression and preventing bacterial infection, respectively. The nanocomposites were incorporated into thermoresponsive gel, made of pluronic and polyethylene glycol. The particle size of AuNPs synthesized using CLRE (AuNPs-CLRE) and HLRE (AuNPs-HLRE) was 202 ± 49 and 190 ± 31 nm, respectively with positive surface charge (+30 to + 45 mV). The thermoresponsive gels containing DsiRNA-AuNPs gelled at 32 ± 1 °C and released the active agents in sufficient amount with good texture and rheological profiles for topical application. DsiRNA-AuNPs and those incorporated into thermoresponsive pluronic gels demonstrated high cell viability, proliferation and cell migration rate via in vitro cultured cells of human dermal fibroblasts, indicating their non-cytotoxicity and wound healing properties. Taken together, the thermoresponsive gels are expected to be useful as a potential dressing that promotes healing of diabetic wounds.

Mesoporous Silica Hybridized With Gadolinium(III) Nanoplatform for Targeted Magnetic Imaging-Guided Photothermal Breast Cancer Therapy

Achieving drug target accumulation in antitumor tissue, simultaneous diagnostic imaging, and optimal release behavior with treatment needs a best chemotherapy procedure involving receptive switch of drug delivery. Constructed on mesoporous silica nanoparticles, which are crossed with multiscale charming nanoparticles for magnetic resonance imaging (MRI)-aided and alternate magnetic field (AMF) response chemotherapy for breast cancer, we report in this work the assembly of a new theranostics drug conveyance process. Hydrothermal processes (gadolinium(III) oxide nanoparticles [Gd-NPs]) and heat decomposition process (radical size uFe-NPs) were used to prepare superparamagnetic Gd-NPs with multiscale sizes. Gadolinium(III) oxide nanoparticles act as an AMF-responsive heat mediator, while ultra-Fe nanoparticles (uFe-NPs) act as an MRI T₂ contrast mediator. Nanoparticles of the mesoporous silica with radially oriented mesochannels were further grown in situ on the surfaces of the Gd-NPs, and the uFe-NPs anticancer drug doxorubicin can be easily incorporated in the mesochannels. To provide better targeting capabilities for the as-synthesized biotin-loaded nanohybrids, the particle surfaces are updated with biotin (Bt). This optimized drug conveyance method based on nanocomposites of SiO₂ demonstrated great efficiency of medication charging and receptive properties of AMF stimulus release. However, tests of MRI in vitro showed an outstanding contrast effect in MRI with a high stimulation quality (299 mM⁻¹ s⁻¹). In contrast, the study of in vitro cytotoxicity assessment revealed that an MRI-directed stimulus-mediated theranostics tool can be used as a drug conveyance device to efficiently treat breast cancer.