Hybrid photoactive nanomaterial composed of gold nanoparticles, pheophorbide-A and hyaluronic acid as a targeted bimodal phototherapy

Investigating the Use of Coumarin Derivatives as Lasers

A benzene ring and a lactone ring combine to form the chemical coumarin. Dye lasers have made significant advances in laser technology. The coumarin molecule itself is a non-fluorescent but it displays high fluorescence when electron-denoting substituents such as sulfonamide, benzopyrone, amine, benzothiazole, hydroxyl, methoxy are substituted at various positions. Substituted coumarin possesses the highest energy properties, photostability, and alteration in electron mobility, and therefore could be effectively used as dye lasers. These are considered some of the best fluorophores due to their outstanding photophysical and photochemical properties, which include high fluorescence quantum yields, great photostability, good functionality, and a wide spectrum range. Various inorganic materials are used in classic laser technology to generate the necessary emission. Inorganic lasers come in various types and can emit light in the electromagnetic spectrum's ultraviolet, visible, or infrared parts. Inorganic lasers have certain limitations, which is why coumarin lasers are becoming increasingly popular due to their many advantages. Compared to inorganic lasers, dye lasers offer far better tunability and cover the entire visible and near-infrared range. They only emit at very few specific wavelengths and in extremely narrow bands. The property is therefore presented in this review.

Nontoxic Natural Polymeric Particle Vehicles Derived from Hyaluronic Acid and Mannitol as Mitomycin C Carriers for Bladder Cancer Treatment

Hyaluronic acid/mannitol (HA/MN)-based particles were designed as mitomycin c (MMC) delivery vehicles through the crosslinking of 1:0, 3:1, 1:3, and 0:1 mole ratios of HA/MN to investigate their potential use in bladder cancer therapy. The HA/MN-MMC particles prepared by the microemulsion crosslinking method were of 0.5-10 μm size with a zeta potential value of -36.7 mV. The MMC carrier potential of the HA/MN-MMC particles was investigated by changing HA/MN ratios in the particle structure. The MMC loading capacity of neat HA particles was 5.3 ± 1.1 mg/g, whereas HA/MN (1:3) particles could be loaded with about three times more drug, for example, 18.4 ± 0.8 mg/g. The kinetic of MMC drug delivery from the HA/MN-MMC particles were tested in vitro in bladder cancer conditions for example, pH 4.5, 6, and 7.4. The HA-MMC particles released approximately 70% of the loaded drug in 300 h, while 43% of the loaded drug was released from the HA/MN-MMC particles within 600 h under physiological conditions, pH 7.4, 37 °C. The cytotoxicity of HA-based particles on healthy L929 fibroblast cells and HTB-9 human bladder cancer cells was investigated in vitro via MTT tests. Bare MMC inhibited about 90% of L929 fibroblast cells even at 100 μg/mL, but the cell viabilities in the presence of HA-MMC and HA/MN-MMC particles were 85 ± 5 and 109 ± 7% at 1000 μg/mL, respectively. The HA/MN-MMC (1:3) particles at 1000 μg/mL were found capable of destroying half of HTB-9 human bladder cancer cells within 24 h. Interestingly, the same particles at 50 μg/mL destroyed almost all the cancer cells with 8 ± 5% cell viability in 72 h of incubation time. The designed HA/MN-MMC (1:3) particles were found to afford a chemotherapeutic effect on the tumor cancers while reducing the toxicity of MMC against L929 fibroblast cells.

Pro-Apoptotic and Immunotherapeutic Effects of Carbon Nanotubes Functionalized with Recombinant Human Surfactant Protein D on Leukemic Cells

Nanoparticles are efficient drug delivery vehicles for targeting specific organs as well as systemic therapy for a range of diseases, including cancer. However, their interaction with the immune system offers an intriguing challenge. Due to the unique physico-chemical properties, carbon nanotubes (CNTs) are considered as nanocarriers of considerable interest in cancer diagnosis and therapy. CNTs, as a promising nanomaterial, are capable of both detecting as well as delivering drugs or small therapeutic molecules to tumour cells. In this study, we coupled a recombinant fragment of human surfactant protein D (rfhSP-D) with carboxymethyl-cellulose (CMC) CNTs (CMC-CNT, 10-20 nm diameter) for augmenting their apoptotic and immunotherapeutic properties using two leukemic cell lines. The cell viability of AML14.3D10 or K562 cancer cell lines was reduced when cultured with CMC-mwCNT-coupled-rfhSP-D (CNT + rfhSP-D) at 24 h. Increased levels of caspase 3, 7 and cleaved caspase 9 in CNT + rfhSP-D treated AML14.3D10 and K562 cells suggested an involvement of an intrinsic pathway of apoptosis. CNT + rfhSP-D treated leukemic cells also showed higher mRNA expression of p53 and cell cycle inhibitors (p21 and p27). This suggested a likely reduction in cdc2-cyclin B1, causing G2/M cell cycle arrest and p53-dependent apoptosis in AML14.3D10 cells, while p53-independent mechanisms appeared to be in operation in K562 cells. We suggest that CNT + rfhSP-D has therapeutic potential in targeting leukemic cells, irrespective of their p53 status, and thus, it is worth setting up pre-clinical trials in animal models.

Hyaluronan-based Multifunctional Nano-carriers for Combination Cancer Therapy

Hyaluronan (HA) is a natural linear polysaccharide that has excellent hydrophilicity, biocompatibility, biodegradability, and low immunogenicity, making it one of the most attractive biopolymers used for biomedical researches and applications. Due to the multiple functional sites on HA and its intrinsic affinity for CD44, a receptor highly expressed on various cancer cells, HA has been widely engineered to construct different drug-loading nanoparticles (NPs) for CD44-targeted anti-tumor therapy. When a cocktail of drugs is co-loaded in HA NP, a multifunctional nano-carriers could be obtained, which features as a highly effective and self-targeting strategy to combat cancers with CD44 overexpression. The HA-based multidrug nano-carriers can be a combination of different drugs, various therapeutic modalities, or the integration of therapy and diagnostics (theranostics). Up to now, there are many types of HA-based multidrug nano-carriers constructed by different formulation strategies, including drug co-conjugates, micelles, nano-gels and hybrid NP of HA and so on. This multidrug nano-carrier takes the full advantages of HA as an NP matrix, drug carriers and targeting ligand, representing a simplified and biocompatible platform to realize the targeted and synergistic combination therapy against the cancers. In this review, recent progress of HA-based multidrug nano-carriers for combination cancer therapy is summarized and the potential challenges for translational applications have been discussed.

Biodegradable Hollow Manganese Silicate Nanocomposites to Alleviate Tumor Hypoxia toward Enhanced Photodynamic Therapy

Photodynamic therapy (PDT) has been extensively explored as a minimally invasive treatment strategy for malignant cancers. It works with the help of a photosensitizer located within cancer cells that is irradiated by near-infrared light to produce potent toxins and singlet oxygen (¹O₂) and induce cell death. However, reactive oxygen species can be overexpressed in tumor tissue because of the rapid metabolic activity in cancer cells, and the insufficient oxygenation (hypoxia) can lead to low production of singlet oxygen (¹O₂) during PDT. In this study, we developed nanocomposites composed of a hollow manganese silicate (HMnOSi) nanoparticle and a photosensitizer (Ce6) that can generate significant amounts of O₂ to relieve tumor hypoxia and enhance the therapeutic efficacy of PDT. Our nanocomposites were characterized by UV-vis, fluorescence spectroscopy, transmission electron microscopy (TEM), energy-dispersive X-ray, and dynamic light scattering. Our particles' hollow mesoporous structures were shown to retain large amounts of Ce6 on the particle surface with high loading capacity (33%). TEM imaging showed that the nanoparticles could be biodegradable over time in simulated body fluid, which can imply clinical potentials. Significant H₂O₂ quenching capabilities to alleviate hypoxic conditions in a solid tumor were also presented. For breast cancer cells, the nanocomposite-treated group revealed that 91% of cells were dead under laser activation compared to 51% for the control group (free Ce6). In an animal study, our nanocomposites showed almost fourfold tumor growth inhibition versus the control and more than twofold over free Ce6 in orthotopic tumor xenografts. In addition, the oxygen saturation contrast inside tumors was evaluated by photoacoustic imaging to demonstrate the alleviated hypoxia in vivo. Our works provide a smart nanosystem to ameliorate the hypoxic tumor microenvironment and augment the efficacy of PDT in a targeted cancer treatment.

Active targeting of gold nanoparticles as cancer therapeutics

Gold nanoparticles (AuNPs) are of increasing interest for their unique properties and their biocompatability, minimal toxicity, multivalency and size tunability make them exciting drug carriers. The functionalisaton of AuNPs with targeting moieties allows for their selective delivery to cancers, with antibodies, proteins, peptides, aptamers, carbohydrates and small molecules all exploited. Here, we review the recent advances in targeted-AuNPs for the treatment of cancer, with a particular focus on these classes of targeting ligands. We highlight the benefits and potential drawbacks of each ligand class and propose directions in which the field could grow.

Hyaluronic Acid-Based Theranostic Nanomedicines for Targeted Cancer Therapy

Hyaluronic acid (HA) is a natural mucopolysaccharide and has many useful advantages, including biocompatibility, non-immunogenicity, chemical versatility, non-toxicity, biodegradability, and high hydrophilicity. Numerous tumor cells overexpress several receptors that have a high binding affinity for HA, while these receptors are poorly expressed in normal body cells. HA-based drug delivery carriers can offer improved solubility and stability of anticancer drugs in biological environments and allow for the targeting of cancer treatments. Based on these benefits, HA has been widely investigated as a promising material for developing the advanced clinical cancer therapies in various formulations, including nanoparticles, micelles, liposomes, and hydrogels, combined with other materials. We describe various approaches and findings showing the feasibility of improvement in theragnosis probes through the application of HA.

Immunohistochemistry of IL-1β, IL-6 and TNF-α in spleens of mice treated with gold nanoparticles

Gold nanoparticles (AuNPs) possess considerable biocompatibility and therefore gaining more attention for their biomedical applications. Previous studies have shown the transient increase in pro-inflammatory cytokines expression in different organs of rats and mice exposed to AuNPs. Structural changes in the spleen of mice treated with AuNPs have also been reported. This investigation was aimed to study the immunostaining of IL-1β, IL-6 and TNF-α in mice treated with different sizes of AuNPs. The animals were divided into 7 groups of 4 animals in each group. One group received saline and served as control. Two sets of three groups were treated with 5 nm, 20 nm and 50 nm diameter AuNPs. One set was sacrificed on day 1 and the other on day 7 following the AuNPs injections. Spleens were dissected out and promptly fixed in formalin for 3 days and then processed for IL-1β, IL-6 and TNF-α immunostaining using target-specific antibodies. The immunoreactivities of IL-1β and IL-6 were increased with the increase of AuNP size. The immunostaining of IL-1β in spleen of 20 nm AuNP treated mice was subsequently decreased on day 7 whereas it persisted in 50 nm AuNP group. The increase in the immunoreactivity of IL-6 on day 1 was decreased on day 7 in the spleens of mice treated with 20 nm or 50 nm AuNPs. The immunostaining of TNF-α was found to be negative in all the treatment groups. In conclusion, the size of AuNPs plays an important role in the expression of proinflammatory cytokines in mouse spleen; small size (5 nm) AuNPs caused minimal effect, whereas larger (50 nm) AuNPs produced intense immunostaining.

Synthesis and Self-Assembly Behavior of Chlorophyll Derivatives for Ratiometric Photoacoustic Signal Optimization

Self-assembly provides researchers powerful tools for creating ordered functional structures and complex architectures. Investigation of in vivo self-assembly reveals the assembly/aggregation-induced retention (AIR) effect and enhanced targeting effect, which can be applied to promising biomedical applications by enhancing molecular accumulation in the target region. These unique bioeffects inspire the interest of researchers in construction of self-assembled nanomaterials in biological systems. Although many efforts have been achieved, the in-depth analysis of the relationship between assemblies and functions is rarely reported. Here, we focus on the relationship of chlorophyll-derivative assemblies and their photoacoustic signals and attempt to establish a method for monitoring the aggregation efficiency in vivo based on photoacoustic signals. Three arginine-rich peptide-purpurin molecules were designed and synthesized. The assembled capabilities and assembly processes of these molecules were characterized and monitored by UV, fluorescence, and CD spectra images of gradually changing polarities in mixed solvents, and the morphologies of the assemblies were observed by TEM. Furthermore, the relationship between the aggregation ratios of the molecules and the ratiometric photoacoustic signals was systemically studied. We prospect that the fundamental research in revealing objective laws will be useful for future guidance in optimizing photoacoustic detection windows and assembled molecule design.

Effect of naked and PEG-coated gold nanoparticles on histopathology and cytokines expression in rat liver and kidneys

Aim: To compare the effects of 5- and 50-nm naked and PEG-coated gold nanoparticles (AuNP) on proinflammatory cytokines (IL-1β, IL-6, TNF-α) expression and histopathological changes in liver and kidneys of rats. Materials & methods: Rats were injected with different nanoparticles and sacrificed after 24 h. Results: Both 5- and 50-nm AuNPs, and 50-nm PEG-AuNPs caused granular clumping of cytoplasm, edema and hydropic dystrophy in hepatic cells. Naked AuNPs of both sizes caused mild shrinkage, whereas 50-nm PEG-AuNPs enlarged the Bowman's space and capsule. Larger nanoparticles produced more profound mRNA expression of cytokines in both the organs. Conclusion: These findings suggest the roles of particle size and coating on immunological response and histopathological changes.

A nano-based thermotherapy for cancer stem cell-targeted therapy

Cancer stem cells (CSCs) exhibit high resistance to conventional therapy and are responsible for cancer metastasis and tumor relapse.

Reproductive Toxicity of Pomegranate Peel Extract Synthesized Gold Nanoparticles: A Multigeneration Study in C. elegans

C. elegans is a preferential model for testing environmental toxicity of compounds including nanomaterials. The impact of multigeneration exposure of gold nanoparticles (AuNPs) on the lifespan and fertility of C. elegans is not known and therefore is investigated in this study. We used pomegranate (Punica granatum) peel extracts as a reducing agent to synthesize gold nanoparticles (PPE-AuNPs) from chloroauric acid. Nematodes were grown till adult stage and then exposed to 25, 50, and 100 μg/ml of PPE-AuNPs at 20°C for 72 hours and then assessed for lifespan and fertility. The same protocols were followed for subsequent F1, F2, and F3 generations. The results showed that PPE-AuNPs dose-dependently but insignificantly reduced the lifespan of C. elegans. Exposure of PPE-AuNPs significantly and dose-dependently reduced the fertility of C. elegans in terms of the number of eggs produced. The reproductive toxicity of PPE-AuNPs was found to be minimal in parental generation (F0) and maximal in F3 generation. In conclusion, biologically synthesized PPE-AuNPs adversely affect the fertility of C. elegans while the factors responsible for reproductive toxicity are inherited by subsequent generations.

Size and time-dependent induction of proinflammatory cytokines expression in brains of mice treated with gold nanoparticles

Gold nanoparticles (GNPs) are among the ideal nano-sized materials for medical applications such as imaging and drug delivery. Considering the significance of recent reports on acute phase induction of inflammatory mediators by GNPs, we studied the effect of GNPs on proinflammatory cytokines gene expression in mouse brain. Group 1 served as control whereas groups 2-4 were given only one intraperitoneal dose of 5, 20 and 50 nm GNPs, respectively and sacrificed after 24 h. The animals in groups 5-7 also received the same treatment but sacrificed after 7 days. Groups 8-10 received two injections of GNPs (5, 20 and 50 nm, respectively), first at the beginning of study and second on day 6, and sacrificed on day 7. Total RNA was extracted from the cerebral tissue and analyzed for the gene expressions of IL-1β, IL-6 and TNF-α. A single injection of 5 nm diameter GNPs significantly increased the mRNA expression of IL-1β and IL-6 in mouse brain on day 7, which was not augmented by the second dose of the same GNPs. Larger size GNPs (20 nm and 50 nm) did not cause any significant change in the expression of proinflammatory cytokines in mouse brain. In conclusion, systemic administration of small sized GNPs (5 nm) induced a proinflammatory cascade in mouse brain indicating a crucial role of GNPs size on immune response. It is important to use the right sized GNPs in order to avoid an acute phase inflammatory response that could be cytotoxic or interfere with the bioavailability of nanomaterials.

Photodynamic Therapy in HeLa Cells Incubated with Riboflavin and Pectin-coated Silver Nanoparticles

Riboflavin (Rf) is an endogenous photosensitizer, which can participate in Type I and Type II processes. We have recently shown that the yield of the triplet excited states of Rf is enhanced in the presence of pectin-coated silver nanoparticles (Pec@AgNP) due to formation of a complex between Rf and Pec@AgNP (Rf-Pec@AgNP). Consequently, under aerobic conditions, the amounts of singlet molecular oxygen and superoxide radical anion generated are also larger in the presence of the nanoparticles. This result made us suspect that the nanoparticles could have a beneficial effect in Rf-based PDT. To prove this hypothesis, we here compared the photodamage in HeLa cells incubated with Rf in the presence and in the absence of Pec@AgNP applying several optical assays. We used fluorescence imaging of irradiated HeLa cells incubated with Annexin V and propidium iodide to evaluate the occurrence of apoptosis/necrosis, the reduction of the tetrazolium dye MTT to formazan and neutral red uptake to prove cell viability, as well as synchrotron infrared microscopy of single cells to evaluate possible structural changes of DNA and nuclear proteins. The enhanced photodamage observed in the presence of Pec@AgNP seems to indicate that Rf enters into the cells complexed with the nanoparticles.

Histopathology of the Liver, Kidney, and Spleen of Mice Exposed to Gold Nanoparticles

Gold nanoparticles (GNPs) are biocompatible nanomaterials that are currently researched for biomedical applications such as imaging and targeted drug delivery. In this investigation, we studied the effects of a single dose (injected on day 1) as well as a priming dose (two injections with a gap of one week) of 5 nm, 20 nm, and 50 nm diameter GNPs on the structural and biochemical changes in the liver, kidney, and spleen of mice. The results showed that small sized GNPs (5 nm) produced significant pathological changes in the liver on day 2 that gradually reduced on day 8. The medium (20 nm) and large (50 nm) sized GNPs preferentially targeted the spleen and caused significant pathological changes to the spleen architecture on day 2 that persisted on day 8 as well. There were minimal and insignificant pathological changes to the kidneys irrespective of the GNPs size. The animals that were primed with the pre-exposure of GNPs did not show any aggravation of histological changes after the second dose of the same GNPs. None of the dose regimens of the GNPs were able to significantly affect the markers of oxidative stress including glutathione (GSH) and malondialdehyde (MDA) in all of the organs that were studied. In conclusion, the size of GNPs plays an important role in their pathological effects on different organs of mice. Moreover, the primed animals become refractory to further pathological changes after the second dose of GNPs, suggesting the importance of a priming dose in medical applications of GNPs.

Bakhiet A, Khan A, A. Khan H. Recent Trends in Biomedical Applications of Nanomaterials

In recent years, there have been enormous developments in utilizing the potential of nanotechnology in different fields including biomedical sciences. The most remarkable biomedical applications of nanoparticles (NPs) are in the diagnosis and treatment of various diseases. Functionalization of NPs renders them unique properties so that they can be used as contrast agent for dual or triple modal imaging. The design and synthesis of new generation NPs aiming at targeted drug delivery has revolutionized the safe and effective therapies for complex and difficult to treat diseases. The theranostic NPs possess the dual capabilities for disease diagnosis and treatment. This review highlights the biomedical applications of NPs based on recent reports published in this area of research.

A priming dose protects against gold nanoparticles-induced proinflammatory cytokines mRNA expression in mice

AIM

To study the effect of priming doses of gold nanoparticles (GNPs) on proinflammatory cytokines in different organs of mice.

MATERIALS & METHODS

Mice were injected with a single or two doses (priming group) of GNPs (5, 20 and 50 nm) and sacrificed after 1 or 7 days. The mRNA expressions of IL-1β, IL-6 and TNF-α were determined in liver, kidney and spleen.

RESULTS

A single injection of 5 nm GNPs significantly increased the mRNA expressions of IL-1β and IL-6 in liver, which were normalized on day 7. In spleen, the GNPs of all sizes significantly increased IL-1β and IL-6 mRNA expressions on day 1 that persisted on day 7. The priming dose of GNPs protected the animals against the acute phase induction of IL-1β and IL-6 expressions in liver and spleen.

CONCLUSION

Primed animals showed protection against GNP-induced acute immune activation suggesting the importance of the priming dose in nanomedicine.

Hyaluronic Acid-Functionalized Gold Nanorods with pH/NIR Dual-Responsive Drug Release for Synergetic Targeted Photothermal Chemotherapy of Breast Cancer

Tumor-targeted delivery of photothermal agent and controlled release of concomitant chemotherapeutic drug are two key factors for combined photothermal chemotherapy. Herein, we developed a pH/near-infrared (NIR) dual-triggered drug release nanoplatform based on hyaluronic acid (HA)-functionalized gold nanorods (GNRs) for actively targeted synergetic photothermal chemotherapy of breast cancer. Targeting folate (FA), dopamine, and adipic acid dihydrazide triconjugated HA was first synthesized and used to decorate GNRs via Au-catechol bonds, and then an anticarcinogen doxorubicin (DOX) was conjugated onto HA moieties via an acid-labile hydrazone linkage, resulting in multifunctional nanoparticles GNRs-HA-FA-DOX. The nanoparticles exhibited excellent stability and had a pH and NIR dual-responsive drug release behavior. In vitro studies showed that the nanoparticles could be efficiently internalized into breast cancer MCF-7 cells and kill them under NIR irradiation in a synergistic fashion via inducing cell apoptosis. Pharmacokinetics and biodistribution studies in tumor-bearing mice indicated that the nanoparticles had a long blood circulation with a half-life of 2.4 h and exhibited a high accumulation of 11.3% in tumor site. The tumors of mice treated with combined chemotherapy and photothermal therapy were completely suppressed without obvious systemic toxicity after 20 d of treatment. These results demonstrated a great potential of GNRs-HA-FA-DOX nanoparticles for targeted synergistic therapy of breast cancer.

Comparative evaluation of immunohistochemistry and real-time PCR for measuring proinflammatory cytokines gene expression in livers of rats treated with gold nanoparticles

Gold nanoparticles (GNPs) possess promising applications in targeted drug delivery and controlled release of a variety of chemical agents. However, the immunocompatibility of GNPs is poorly understood. After exposure, GNPs preferentially tend to accumulate is liver, where they induce an acute phase proinflammatory response. We therefore compared the two techniques, immunohistochemistry and real-time PCR for measuring the protein and mRNA expressions of IL-1β, IL-6 and TNF-α in liver of rats after intraperitoneal injections (5μg/animal) of 10 and 50nm diameter GNPs for 1 and 5days. The results showed that both 10nm and 50nm GNPs induced an acute phase expression of proinflammatory cytokines that receded on day 5. The proinflammatory response on day 1 was comparatively more severe with 50nm GNPs than 10nm GNPs. A comparative evaluation between immunostaining and real-time PCR showed that the latter technique is more sensitive as it could detect the cytokines mRNA expression in control samples as well. This could be partly attributed to the amplification strategy used in real-time PCR and partly to the variations in the half lives of cytokines mRNA and their resulting proteins.

Hyaluronic acid for anticancer drug and nucleic acid delivery

Hyaluronic acid (HA) is widely used in anticancer drug delivery, since it is biocompatible, biodegradable, non-toxic, and non-immunogenic; moreover, HA receptors are overexpressed on many tumor cells. Exploiting this ligand-receptor interaction, the use of HA is now a rapidly-growing platform for targeting CD44-overexpressing cells, to improve anticancer therapies. The rationale underlying approaches, chemical strategies, and recent advances in the use of HA to design drug carriers for delivering anticancer agents, are reviewed. Comprehensive descriptions are given of HA-based drug conjugates, particulate carriers (micelles, liposomes, nanoparticles, microparticles), inorganic nanostructures, and hydrogels, with particular emphasis on reports of preclinical/clinical results.