Synthesis and Characterization of Pyrogallol Silver Nanoparticles and Pyrogallol Nanocomposites and Their Effects on Radiation-Induced Toxicity in HEK293 Cells

Nanoscience Chemistry Medicinal Chemistry Bioengineering Oncology Life Sciences Medicine
nanoparticles nanocomposites radiation cell protection anti-inflammatory apoptosis biomedical applications

Academic Background

Cancer is a complex and highly prevalent disease worldwide, causing nearly 10 million deaths annually. Early diagnosis and effective treatment are crucial for improving patient survival rates. Current cancer treatment modalities include surgery, chemotherapy, radiotherapy, and immunotherapy. Among these, radiotherapy is a critical component of cancer treatment, particularly for postoperative patients, as it significantly reduces the risk of local tumor recurrence. However, radiotherapy also presents challenges, such as the development of radioresistance in cancer cells and radiation-induced toxicity in surrounding normal cells. This toxicity not only affects treatment efficacy but may also cause long-term harm to patients’ health.

In recent years, advancements in nanotechnology have provided new avenues for cancer treatment. Nanoparticles and nanocomposites have garnered significant attention due to their unique biomedical applications. Their high surface-area-to-volume ratio enhances drug bioavailability and targeting. Specifically, nanomaterials derived from plant extracts, such as pyrogallol, are considered promising for mitigating radiation-induced toxicity due to their antioxidant, anti-inflammatory, and antimicrobial properties.

Research Source

This study was conducted by a collaborative research team from institutions including Sastra Deemed University in India and Konkuk University in South Korea. The paper was accepted on March 27, 2025, and published in the journal Bionanoscience. The research team included authors such as Abirami R, Roshini Ramamurthy, and Sreemadhi Parvathikandhan, and the study was funded by the Department of Science and Technology, India.

Research Process

1. Synthesis of Pyrogallol Silver Nanoparticles (PyNP)

The study first synthesized pyrogallol silver nanoparticles using a two-step process. The specific steps were as follows: - A 1 mM pyrogallol solution was mixed with a 1 mM silver nitrate solution, with color changes during the reaction indicating nanoparticle formation. - The resulting nanoparticles were lyophilized, and the reaction process was monitored using a UV-Vis spectrophotometer.

2. Synthesis of Chitosan Nanoparticles

Chitosan nanoparticles were synthesized as follows: - Chitosan was dissolved in a 2% acetic acid solution, and sodium tripolyphosphate (STPP) was added as a crosslinker. The mixture was stirred, centrifuged, and dried.

3. Synthesis of Pyrogallol Nanocomposite (PyNC)

The synthesized chitosan nanoparticles were mixed with pyrogallol nanoparticles, and glutaraldehyde was added as a crosslinking agent. The mixture was stirred, allowed to settle for 24 hours, and the precipitate was collected and dried.

4. Characterization of Nanomaterials

Various techniques were used to characterize the synthesized nanomaterials: - Scanning Electron Microscopy (SEM): Morphology and size of the nanoparticles were observed. - Dynamic Light Scattering (DLS): Particle size distribution was measured. - Zeta Potential Analysis: Surface charge and stability of the nanoparticles were assessed. - Fourier Transform Infrared Spectroscopy (FTIR): Chemical bonds and functional groups of the nanomaterials were analyzed.

5. Cell Experiments

Human embryonic kidney cells (HEK293) were used in the experiments, divided into six groups: control, radiation, radiation + PyNP, radiation + PyNC, PyNP alone, and PyNC alone. The experimental process included: - Cell Culture: Cells were cultured at 37°C with 5% CO₂ using DMEM medium. - Radiation Treatment: Cells were irradiated with 10 Gy of X-rays using a linear accelerator (Linac). - Cell Viability Assay: Cell viability was detected using the MTT assay, and cell survival rates were calculated. - RNA Extraction and qPCR Analysis: Total RNA was extracted from cells, and gene expression was analyzed using reverse transcription quantitative PCR (RT-qPCR).

Key Results

1. Characterization of Nanomaterials

  • SEM Analysis: Pyrogallol nanoparticles were spherical with an average size of 0.36 μm. In the nanocomposite, pyrogallol nanoparticles were tightly bound to chitosan nanoparticles.
  • DLS Analysis: The average particle size of pyrogallol nanoparticles was 133.0 nm, while that of the nanocomposite was 463.3 nm.
  • Zeta Potential: The zeta potentials of pyrogallol nanoparticles and the nanocomposite were -13.5 mV and -21.4 mV, respectively, indicating good stability.
  • FTIR Analysis: The infrared spectra of pyrogallol nanoparticles and the nanocomposite showed characteristic peaks for functional groups such as OH and C=O.

2. Cell Experiment Results

  • Cell Viability: PyNP and PyNC exhibited the highest cell viability at concentrations of 50 μg/mL and 20 μg/mL, respectively.
  • Gene Expression: In the radiation group, pro-apoptotic genes (e.g., Bax, Caspase-3, Caspase-7) were upregulated, while anti-apoptotic genes (e.g., Bcl-2) were downregulated. In the radiation + PyNP and radiation + PyNC groups, these gene expression trends were reversed, indicating that PyNP and PyNC could reduce radiation-induced apoptosis.
  • Inflammation and Fibrosis-Related Genes: In the radiation group, the expression of inflammation and fibrosis-related genes such as TGF-β1, IL-1α, and IL-7 was significantly increased. Treatment with PyNP and PyNC significantly reduced the expression of these genes.

Research Conclusion

This study demonstrates that pyrogallol silver nanoparticles and pyrogallol nanocomposites can effectively protect normal cells from radiation-induced damage. By modulating the expression of genes related to apoptosis, inflammation, and fibrosis, these nanomaterials show great potential in reducing the side effects of radiotherapy. The findings provide a critical basis for developing novel adjuvant therapies for radiotherapy and lay the groundwork for further exploration of nanomaterials in cancer treatment.

Research Highlights

  1. Innovative Nanomaterials: Pyrogallol was combined with silver nanoparticles and chitosan for the first time to develop nanocomposites with radioprotective properties.
  2. Multidimensional Characterization: Comprehensive characterization of nanomaterials was conducted using SEM, DLS, zeta potential, and FTIR.
  3. Mechanistic Insights: The study delved into the mechanisms of PyNP and PyNC in apoptosis, inflammation, and fibrosis.
  4. Clinical Application Potential: The findings offer new therapeutic strategies for reducing radiotherapy side effects, with significant clinical implications.

Research Significance

This study not only provides new insights into the application of nanomaterials in cancer treatment but also lays the foundation for developing safer and more effective adjuvant therapies for radiotherapy. By reducing radiation-induced damage to normal cells, PyNP and PyNC have the potential to enhance the efficacy of radiotherapy and improve patients’ quality of life. Future research could further explore the application of these nanomaterials in other cancer types, as well as their long-term safety and efficacy.