جستجوی مقالات مرتبط با کلیدواژه "radioprotective" در نشریات گروه "پزشکی"

Radiotherapy, a highly effective method of radiation-based treating cancers, can reduce the size of tumors and affect healthy tissues. Radiation-induced lymphopenia as a side effect of radiation therapy can reduce the effectiveness of the treatment.
This study aimed to examine how taurine can protect peripheral blood lymphocytes from radiation-based apoptosis.
In this experimental study, the effects of the taurine on lymphocytes were studied, and blood samples were divided into three groups: a negative control group that was not treated, a positive control group that was treated with cysteine (100 μg/ml), and a group that was treated with taurine (100 µg. mL-1) in three different doses (4, 8 & 12 Gy) before irradiation. The percentage of apoptotic and necrotic lymphocytes was measured using flow cytometry 48 and 72 hours after the irradiation, respectively.
According to the groups treated with taurine, the number of lymphocytes undergoing apoptosis was lower and higher compared to the negative and positive control groups, respectively. The decrease in this value was more pronounced 48 hours after radiation compared to 72 hours. Furthermore, there was a slight increase in the number of apoptotic lymphocytes with increasing radiation dose. 
Taurine effectively protects human peripheral blood lymphocytes from radiation-based apoptosis.

The Mentha-Pulegium essential oil (MP-EO) contains different antioxidant compounds and reduces the indirect effects of dispersed ionizing radiation on biological systems.

The current study aimed to assess a possible radio-protective effect of MP-EO on peripheral blood mononuclear cells (PBMCs).

In this experimental study, MP-EO was firstly prepared and PBMCs were then irradiated in various groups with doses of 25 and 200 cGy of X-rays in the presence of IC10 of MP-EO. After incubation times of 48h and 72h, the survival, apoptosis, and necrosis percentages of PBMCs were determined by MTT assay and flow cytometry analyses; the radio-protective effect of MP-EO was examined.

In the presence of 80 µg/ml (IC10) MP-EO, the mean survival percentage of irradiated PBMCs by radiation doses of 25 and 200 cGy was significantly increased after 48h of incubation compared with the control. At 72h of incubation, the mean survival percentage of irradiated PBMCs was significantly increased only at 25 cGy. The percentage of apoptosis and necrosis of PBMCs was significantly reduced in the presence of the MP-EO at both incubation times and radiation doses; therefore, the highest reduction was at 200 cGy and 48h incubation compared to the control.

MP-EO as a natural, non-toxic, and cost-effective compound can exhibit a favorable in-vitro radio-protective effect by increasing the survival and decreasing the percentage of apoptosis and necrosis of irradiated PBMCs.

Radiodermatitis (RD) is experienced by many cancer patients ‎receiving radiotherapy. An increasing number of these patients demand alternative natural therapies. This study aimed to review the natural products application in cancer patients who experience RD.‎ A search of studies published from 1990 to ‎‎2020 in the ‎databases including PubMed, Scopus, and Google Scholar was performed with the keywords relevant to “Radiotherapy” “Dermatitis” and “Natural Products”. Out of 73 papers obtained, 40 papers were excluded which described only protocols or were non-clinical, non-English language, or without full text. The obtained studies were ‎discussed in detail according to the outcomes and potential mechanisms of action for each natural ‎product.‎ Clinically studied natural products were found to show several outcomes from non-effective to effective in diminishing various items of RD. Outcomes on the effectiveness of Aloe vera were diverse. Some trials suggest that Silybum marianum, Boswellia, Nigella sativa, olive oil, Lianbai, and Hypericum perforatum as well as some multi-ingredient products might be effective prophylactic treatments for RD. Potential mechanisms of these natural products included topical hydrating, anti-inflammatory, antioxidant, and wound ‎healing activities. Results from this review shows that there are some promising natural product options for the prevention and treatment of RD via their multifactorial bioactivities. However, additional research is needed before any definitive conclusions. A larger sample size, optimum doses and duration of intervention as well as investigation of treatment effects in diverse populations and comorbid complications would also be essential in future studies.

It has long been known that ionizing radiation can lead to detrimental effects in normal cells. In this light, Radioprotective chemicals have been used to decrease morbidity or mortality caused by ionizing irradiation. This study aimed to evaluate the radio-protective effect of N-acetylcysteineagainst radiation-induced mortality in male mice.
52 healthy male mice were divided into four groups including NAC before irradiation (1), irradiation (2), NAC after irradiation (3) NAC before irradiation (4) and control. Three groups were treated orally with 100 mg/ kg of NAC. Gamma irradiation was performed at 8 Gy using a Co-60 machine. Kaplan-Meier method and the log-rank test were performed, using SPSS version 16. The significance level was considered to be 0.05.
The statistical analysis revealed a significant difference between the test and control groups (P>0.05). The percentage of survival after 30 days was 46.2% for the irradiation group (1). In addition, the percentage of decreased lifespan was calculated at 5.90%, 23.60% and 17.93% for the first-third groups, respectively.
Results revealed lack of effectiveness of treatment with NAC after lethal dose. These results suggested that application of NAC for mice before irradiation protected them from the lethal effects of whole-body irradiation.

The aim of this study was to investigate the radioprotective effect of thymol as a natural product against salivary glands dysfunction induced by ionizing radiation in rats. The rats were treated with thymol at dose of 50 mg/Kg before exposure to radiation at dose 15Gy. Salivary gland function was evaluated with radioisotope scintigraphy and then salivary gland to background counts ratio was calculated. Ionizing radiation caused significant salivary glands dysfunction at the 3th and the 70th days with reduction in radioactivity uptake in salivary glands. Ratios of salivary gland to background radioactivities were 2.0±0.05, 1.58±0.62 and 1.99±0.07 at 3th days for control, radiation, and thymol plus radiation groups, respectively. Thymol significantly protected acute and chronic salivary gland dysfunction induced by ionizing radiation in the rats. This finding may have been a promising application of thymol for the protection of salivary glands dysfunction induced by ionizing irradiation in patients exposed to radiation in head and neck cancer therapy

Critical macromolecules such as DNA maybe damaged by free radicals that are generated from the interaction of ionizing radiation with biological systems. Melatonin and vitamin C have been shown to be direct free radical scavengers. The aim of this study was to investigate the in vivo/in vitro radioprotective effects of melatonin and vitamin C separately and combined against genotoxicity induced by 6 MV x-ray irradiation in human cultured blood lymphocytes.
In this experimental study, fifteen volunteers were divided into three groups of melatonin, vitamin C and melatonin plus vitamin C treatment. Peripheral blood samples were collected from each group before, and 1, 2 and 3 hours after melatonin and vitamin C administration (separately and combined). The blood samples were then irradiated with 200 cGy of 6 MV x-ray. In order to characterize chromosomal aberrations, the lymphocyte samples were cultured with mitogenic stimulus on cytokinesisblocked binucleated cells.
The samples collected 1hour after melatonin and vitamin C (separately and combined) ingestion exhibited a significant decrease in the incidence of micronuclei compared with their control group (P We conclude that simultaneous administration of melatonin and vitamin C as radioprotector substances before irradiation may reduce genotoxicity caused by x-ray irradiation.