Protective and therapeutic potential of melatonin against intestinal diseases: updated review of current data based on molecular mechanisms.

INTRODUCTION: Intestinal diseases, a leading global cause of mortality and morbidity, carry a substantial socioeconomic burden. Small and large intestines play pivotal roles in gastrointestinal physiology and food digestion. Pathological conditions, such as gut dysbiosis, inflammation, cancer, therapy-related complications, ulcers, and ischemia, necessitate the urgent exploration of safe and effective complementary therapeutic strategies for optimal intestinal health. AREAS COVERED: This article evaluates the potential therapeutic effects of melatonin, a molecule with a wide range of physiological actions, on intestinal diseases including inflammatory bowel disease, irritable bowel syndrome, colon cancer, gastric/duodenal ulcers and other intestinal disorders. EXPERT OPINION: Due to anti-inflammatory and antioxidant properties as well as various biological actions, melatonin could be a therapeutic option for improving digestive disorders. However, more researches are needed to fully understand the potential benefits and risks of using melatonin for digestive disorders.

Multimodal cancer cell therapy using Au@Fe2O3 core-shell nanoparticles in combination with photo-thermo-radiotherapy.

In this study, gold coated iron oxide nanoparticle (Au@Fe2O3 NP) was synthesized in a core-shell structure. Photothermal and radiosensitization effects of Au@Fe2O3 NPs were investigated on KB human mouth epidermal carcinoma cell line. Cell death and apoptosis were measured to study the effects of nanoparticles in combination with both radiotherapy (RT) and photothermal therapy (PTT). The KB cells were treated with Au@Fe2O3 NPs (20 µg/ml; 4 h) and then received different treatment regimens of PTT and/or RT using laser (808 nm, 6 W/cm2, 10 min) and/or 6 MV X-ray (single dose of 2 Gy). Following the various treatments, MTT assay was performed to evaluate the cell survival rate. Also, the mode of cell death was determined by flow cytometry using an annexinV-fluorescein isothiocyanate/propidium iodide apoptosis detection kit. No significant cell death was observed due to laser irradiation. The viability of the cells firstly incubated with NPs and then exposed to the laser was significantly decreased. Additionally, our results demonstrated that Au@Fe2O3 NP is a good radiosensitizer at megavoltage energies of X-ray. When nanoparticles loaded KB cells were received both laser and X-ray, the cell viability substantially decreased. Following such a combinatorial treatment, flow cytometry determined that the majority of cell death relates to apoptosis. In conclusion, Au@Fe2O3 NP has a great potential to be applied as a photo-thermo-radiotherapy sensitizer for treatment of head and neck tumors.