Optimal conditions of LDR to protect the kidney from diabetes: exposure to 12.5 mGy X-rays for 8 weeks efficiently protects the kidney from diabetes

High-Fat Diet and Altered Radiation Response

High-fat diets (HFDs) have become increasingly prevalent in modern societies, driving rising rates of obesity and metabolic syndrome. Concurrently, radiation exposure from medical treatments and environmental sources poses health risks shaped by both biological and environmental factors. This review explores the intersection between HFDs and radiation sensitivity/susceptibility, focusing on how diet-induced metabolic alterations influence the body's response to radiation. Evidence from preclinical and clinical studies indicates that HFDs significantly alter metabolism, leading to increased oxidative stress and immune system dysregulation. These metabolic changes can exacerbate radiation-induced oxidative stress, inflammation, and DNA damage, potentially increasing radiation sensitivity in normal tissues. Conversely, obesity and HFD-induced metabolic disruptions may activate cellular pathways involved in DNA repair, cell survival, and inflammatory responses, fostering tumor resistance and modifying the tumor microenvironment, which may impair the efficacy of radiation therapy in cancer treatment. Understanding the interplay between diet and radiation exposure is critical for optimizing public health guidelines and improving therapeutic outcomes. These findings underscore the need for further research into dietary interventions that may mitigate radiation-associated risks.

Radiation dose rate effects: what is new and what is needed?

Despite decades of research to understand the biological effects of ionising radiation, there is still much uncertainty over the role of dose rate. Motivated by a virtual workshop on the "Effects of spatial and temporal variation in dose delivery" organised in November 2020 by the Multidisciplinary Low Dose Initiative (MELODI), here, we review studies to date exploring dose rate effects, highlighting significant findings, recent advances and to provide perspective and recommendations for requirements and direction of future work. A comprehensive range of studies is considered, including molecular, cellular, animal, and human studies, with a focus on low linear-energy-transfer radiation exposure. Limits and advantages of each type of study are discussed, and a focus is made on future research needs.

Optimal LDR to Protect the Kidney From Diabetes: Whole-Body Exposure to 25 mGy X-rays Weekly for 8 Weeks Efficiently Attenuates Renal Damage in Diabetic Mice

To explore an optimal frequency of whole-body low-dose radiation (LDR) to protect the kidney from diabetes, type 1 diabetic mice were induced with multiple injections of low-dose streptozotocin in male C57BL/6J mice. Diabetic or age-matched normal mice received whole-body exposure to 12.5 or 25 mGy either every other day or weekly for 4 or 8 weeks. Diabetes decreased the urinary creatinine and increased the microalbumin in urine, renal accumulation of 3-nitrotyrosine and 4-hydroxynonenal, and renal expression of collagen IV and fibronectin. All these renal pathological and functional changes in diabetic mice were significantly attenuated by exposure to LDR at all regimens. However, whole-body exposure of diabetic mice to 25 mGy weekly and to 12.5 mGy every other day for 8 weeks provided a better prevention of diabetic nephropathy than other LDR regimens. Furthermore, whole-body exposure to 25 mGy weekly for 8 weeks showed no detectable effect on the kidney of normal mice, but whole-body exposure to normal mice at 12.5 mGy every other day for 8 weeks increased urinary microalbumin and renal expression of collagen IV and fibronectin. These results suggest that whole-body exposure to LDR at 25 mGy weekly is the optimal condition of LDR to protect the kidney from diabetes.