Potential enhancement of intravenous nano-hydroxyapatite in high-intensity focused ultrasound ablation for treating hepatocellular carcinoma in a rabbit model

Nanotechnology strategies for hepatocellular carcinoma diagnosis and treatment

Hepatocellular carcinoma (HCC) is a common malignancy threatening human health, and existing diagnostic and therapeutic techniques are facing great challenges. In the last decade or so, nanotechnology has been developed and improved for tumor diagnosis and treatment. For example, nano-intravenous injections have been approved for malignant perivascular epithelioid cell tumors. This article provides a comprehensive review of the applications of nanotechnology in HCC in recent years: (I) in radiological imaging, magnetic resonance imaging (MRI), fluorescence imaging (FMI) and multimodality imaging. (II) For diagnostic applications in HCC serum markers. (III) As embolic agents in transarterial chemoembolization (TACE) or directly as therapeutic drugs. (IV) For application in photothermal therapy and photodynamic therapy. (V) As carriers of chemotherapeutic drugs, targeted drugs, and natural plant drugs. (VI) For application in gene and immunotherapy. Compared with the traditional methods for diagnosis and treatment of HCC, nanoparticles have high sensitivity, reduce drug toxicity and have a long duration of action, and can also be combined with photothermal and photodynamic multimodal combination therapy. These summaries provide insights for the further development of nanotechnology applications in HCC.

The protective role of CsNPs and CurNPs against DNA damage, oxidative stress, and histopathological and immunohistochemical alterations induced by hydroxyapatite nanoparticles in male rat kidney

Hydroxyapatite nanoparticles (HAP-NPs) are an inorganic component of natural bone and are mainly used in the tissue engineering field due to their bioactivity, osteoconductivity, biocompatibility, non-inflammatory, and non-toxicity properties. However, the current toxicity data for HAP-NPs regarding human health are limited, and only a few results from basic studies have been published. Therefore, the present study was designed to investigate the beneficial role of chitosan nanoparticles (CsNPs) and curcumin nanoparticles (CurNPs) in alleviating nephrotoxicity induced by HAP-NPs in male rats. The results showed that HAP-NPs caused a reduction in antioxidant enzymes and induced lipid peroxidation, nitric oxide production and DNA oxidation. Moreover, HAP-NP administration was associated with intense histologic changes in kidney architecture and immunoreactivity to proliferating cell nuclear antigen (PCNA). However, the presence of CsNPs and/or CurNPs along with HAP-NPs reduced the levels of oxidative stress through improving the activities of antioxidant enzymes. Also, the rats administered the nanoparticles showed a moderate improvement in glomerular damage which matched that of the control group and showed mild positive reactions to PCNA-ir in glomeruli and renal tubules in the cortical and medullary portions. These novel insights confirm that the presence of chitosan and curcumin in nanoforms has powerful biological effects with enhanced bioactivity and bioavailability phenomena compared to their microphase counterparts. Also, they were able to ameliorate the nephrotoxicity induced by HAP-NPs.

Oxidative stress and DNA damage in zebrafish liver due to hydroxyapatite nanoparticles-loaded cadmium

This study investigated the acute and sub-acute toxicity responses in zebrafish following their exposure to hydroxyapatite-loaded cadmium nanoparticles (nHAP-Cd). The results indicate that cadmium chloride (Cd²⁺), 20 nm nHAP-Cd (nHAP₂₀-Cd), and 40 nm nHAP-Cd (nHAP₄₀-Cd) caused toxicity in zebrafish; the toxicity levels were in the following order: Cd²⁺ > nHAP₂₀-Cd > nHAP₄₀-Cd. Furthermore, nHAP-Cd showed level II grade of acute toxicity in zebrafish; the gradation was done on the guidelines of the Organization for Economic Co-operation and Development 203. We also found that Cd²⁺ ions and nHAP-Cd affected the malondialdehyde (MDA) levels and membrane permeability of zebrafish livers; these effects were compliant with the changes in antioxidant levels. The results of enzyme assays indicate the following notion: following the exposure of zebrafish to 0.12-0.93 mg/L nHAP-Cd, the activities of peroxidase, superoxide dismutase, and catalase enzymes increased significantly. Moreover, the content of anti-superoxide anion also increased substantially. This increasing trend of enzymatic activity was observed until the concentration of nHAP-Cd reached 1.86 mg/L nHAP-Cd. By increasing the concentration of both Cd²⁺ and nHAP-Cd, we found that levels of DNA damage had increased substantially in zebrafish liver; this effect was visualized by performing comet assay.

Hydroxyapatite as a Vehicle for the Selective Effect of Superparamagnetic Iron Oxide Nanoparticles against Human Glioblastoma Cells

Despite the early promises of magnetic hyperthermia (MH) as a method for treating cancer, it has been stagnating in the past decade. Some of the reasons for the low effectiveness of superparamagnetic nanoparticles (SPIONs) in MH treatments include (a) low uptake in cancer cells; (b) generation of reactive oxygen species that cause harm to the healthy cells; (c) undeveloped targeting potential; and (d) lack of temperature sensitivity between cancer cells and healthy cells. Here we show that healthy cells, including human mesenchymal stem cells (MSCs) and primary mouse kidney and lung fibroblasts, display an unfavorably increased uptake of SPIONs compared to human brain cancer cells (E297 and U87) and mouse osteosarcomas cells (K7M2). Hydroxyapatite (HAP), the mineral component of our bones, may offer a solution to this unfavorably selective SPION delivery. HAP nanoparticles are commended not only for their exceptional biocompatibility but also for the convenience of their use as an intracellular delivery agent. Here we demonstrate that dispersing SPIONs in HAP using a wet synthesis method could increase the uptake in cancer cells and minimize the risk to healthy cells. Specifically, HAP/SPION nanocomposites retain the superparamagnetic nature of SPIONs, increase the uptake ratio between U87 human brain cancer cells and human MSCs versus their SPION counterparts, reduce migration in a primary brain cancer spheroid model compared to the control, reduce brain cancer cell viability compared to the treatment with SPIONs alone, and retain the viability of healthy human MSCs. A functional synergy between the two components of the nanocomposites was established; as a result, the cancer versus healthy cell (U87/MSC) selectivity in terms of both the uptake and the toxicity was higher for the composite than for SPIONs or HAP alone, allowing it to be damaging to cancer cells and harmless to the healthy ones. The analysis of actin cytoskeleton order at the microscale revealed that healthy MSCs and primary cancer cells after the uptake of SPIONs display reduced and increased anisotropy in their cytoskeletal arrangement, respectively. In contrast, the uptake of SPION/HAP nanocomposites increased the cytoskeletal anisotropy of both the healthy MSCs and the primary cancer cells. In spite of the moderate specific magnetization of HAP/SPION nanohybrids, reaching 15 emu/g for the 28.6 wt % SPION-containing composite, the cancer cell treatment in an alternating magnetic field resulted in an intense hyperthermia effect that increased the temperature by ca. 1 °C per minute of exposure and reduced the cell population treated for 30 min by more than 50%, while leaving the control populations unharmed. These findings on nanocomposites of HAP and SPIONs may open a new avenue for cancer therapies that utilize MH.

Investigation of chronic toxicity of hydroxyapatite nanoparticles administered orally for one year in wistar rats

Although the toxicity/biocompatibility of hydroxyapatite nanoparticles (nano HA), a prospective nano biomaterial is extensively studied, its interaction on biological systems following chronic exposure is less exploited. In the present study, Wistar rats were given various concentrations of nano HA in the diet to determine the chronic toxicity and potential carcinogenicity. Altogether 140 rats were used for the study under various administration dosages along with control. The animals were sacrificed after 12months of controlled continuous dosing. All in-life parameters, including body weight, food consumption, clinical observations, survival, biochemical and hematology, were unaffected by the chronic exposure of nano HA orally. Similarly, gross and histopathological evaluation was also unchanged following exposure to nano HA. No evidence of nano HA-related lesions or Nano HA-induced neoplasia was suggested in this rodent bioassay study.

Calcium Phosphate as a Key Material for Socially Responsible Tissue Engineering

Socially responsible technologies are designed while taking into consideration the socioeconomic, geopolitical and environmental limitations of regions in which they will be implemented. In the medical context, this involves making therapeutic platforms more accessible and affordable to patients in poor regions of the world wherein a given disease is endemic. This often necessitates going against the reigning trend of making therapeutic nanoparticles ever more structurally complex and expensive. However, studies aimed at simplifying materials and formulations while maintaining the functionality and therapeutic response of their more complex counterparts seldom provoke a significant interest in the scientific community. In this review we demonstrate that such compositional simplifications are meaningful when it comes to the design of a solution for osteomyelitis, a disease that is in its natural, non-postoperative form particularly prevalent in the underdeveloped parts of the world wherein poverty, poor sanitary conditions, and chronically compromised defense lines of the immune system are the norm. We show that calcium phosphate nanoparticles, which are inexpensive to make, could be chemically designed to possess the same functionality as a hypothetic mixture additionally composed of: (a) a bone growth factor; (b) an antibiotic for prophylactic or anti-infective purposes; (c) a bisphosphonate as an antiresorptive compound; (d) a viral vector to enable the intracellular delivery of therapeutics; (e) a luminescent dye; (f) a radiographic component; (g) an imaging contrast agent; (h) a magnetic domain; and (i) polymers as viscous components enabling the injectability of the material and acting as carriers for the sustained release of a drug. In particular, calcium phosphates could: (a) produce tunable drug release profiles; (b) take the form of viscous and injectable, self-setting pastes; (c) be naturally osteo-inductive and inhibitory for osteoclastogenesis; (d) intracellularly deliver bioactive compounds; (e) accommodate an array of functional ions; (f) be processed into macroporous constructs for tissue engineering; and (g) be naturally antimicrobial. All in all, we see in calcium phosphates the presence of a protean nature whose therapeutic potentials have been barely tapped into.