Is growth hormone a radioprotective agent?

There is currently substantial clinical interest in growth hormone (GH) as a protective agent against radiation-related normal tissue injury. To further assess the potential radiation injury-preventive effects of GH, these effects were studied in rats by using a radiation-induced skin injury model. Group 1 received neither GH nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (radiation group). Group 3 and 4 received the same irradiation plus either 0.01 U/kg/day GH (RT + 0.01 GH group) or 0.02 U/kg/day GH (RT + 0.02 GH group) subcutaneously. Clinically and histopathologically, acute skin reactions were assessed by two independent experts in radiation oncology and pathology, respectively. Irradiation increased dermatitis in rats when compared with the control group. The severity of radiodermatitis in the rats in the RT + 0.01 GH and RT + 0.02 GH groups was significantly lower than that in the RT group; radiodermatitis developed earlier in the RT group than in the other groups. GH was efficacious in preventing epidermal atrophy, dermal degeneration such as oedema and collagen fibre loss, and hair follicle atrophy, but not better than in the control group. These results are preliminary to studies that will be performed with higher doses of GH in radiation-treated cancer patients, with the aim of reducing radiation-induced toxicity.

The effects of oral zinc sulphate during radiotherapy on anti-oxidant enzyme activities in patients with head and neck cancer: a prospective, randomised, placebo-controlled study.

The purpose was to determine the effects of oral zinc sulphate along with radiotherapy on anti-oxidant enzyme activities in patients with head and neck cancer. Thirty patients with head and neck cancer were randomly assigned to receive either zinc sulphate capsules (including 50 mg zinc) (n = 15) or placebo (n = 15) three times a day, starting on the day of the first radiotherapy fraction and continuing throughout the scheduled radiotherapy course including weekends and 6 weeks after radiotherapy. The patients were treated with telecobalt radiation at conventional fractionation of 2 Gy/fraction and five fractions/ week in 20-35 fractions for a period of 4-7 weeks. Blood samples for biochemical parameters were collected after an overnight fast (12 h) before radiotherapy, the first day and 6 weeks after radiotherapy. In the placebo group, three patients were excluded. No difference was detected in any final measurement activities of erythrocyte anti-oxidant enzyme such as copper-zinc superoxide dismutase (Cu-Zn SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the direct comparison between the zinc sulphate and the placebo group, except erythrocyte SOD activities measured the first day after radiotherapy (p < 0.03). In the respective measurement analysis of the groups in themselves, in the zinc sulphate group, while the statistical analysis for the activities of erythrocyte CAT and GSH-Px were significantly different (chi2 = 12.4, p < 0.05; chi2 = 8.9, p < 0.05, respectively) before radiotherapy, the first day and 6 weeks after radiotherapy, the activities of SOD did not differ (chi2 = 4.2, p > 0.05). In these three measurements, there was no statistical significance in the activities of enzymes in erythrocyte Cu-Zn SOD, CAT and GSH-Px in the placebo group. Before radiotherapy, plasma zinc levels were normal in 16 patients (59.2%) and were lower in 11 patients (40.8%) compared with laboratory levels. It would be worthwhile studying the effect of oral zinc sulphate supplements to improve the anti-oxidant enzyme activity in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity.

Protective role of intramuscularly administered vitamin E on the levels of lipid peroxidation and the activitiesof antioxidant enzymes in the lens of rats made cataractous with gamma-irradiation.

PURPOSE: To determine the antioxidant role of vitamin E (VE) (10 mg/kg/day) against radiation-induced cataract in lens after total-cranium irradiation of rats with a single dose of 5 Gy. METHODS: Sprague-Dawley rats were divided into three groups. Group 1 did not receive VE or irradiation but received both 0.1 ml physiologic saline intraperitoneally and sham irradiation (control group). Group 2 received to total cranium 5 Gy of gamma irradiation as a single dose (RT group) plus 0.1 ml physiologic saline intraperitoneally. Group 3 received irradiation to total cranium plus 10 mg/kg/day VE (RT+VE group). The rats were irradiated using a cobalt-60 teletherapy unit. Chylacks cataract classification (1) was used in this study. At the end of 10 days, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes (the activity of superoxide dismutase [SOD], glutathione peroxidase [GSH-Px]) and lipid peroxidation level (malondialdehyde [MDA]). RESULTS: While grade 1 cataract development was detectable in seven rats in the RT group, it was detectable only in two rats in the RT+VE group, whereas none of the rats in the control group exhibited any biomicroscopic change in their lenses. MDA level and GSH-Px activity in the rat lens in the RT group was significantly higher than in the control group. SOD activity in the RT group was lower than in the control group. The activity of SOD and GSH-Px enzymes was higher in the RT+VE group, but MDA level was lower in the RT+VE group when compared with the RT group. CONCLUSIONS: Vitamin E has a protective effect on radiation-induced cataract by decreasing oxidative stress. (Eur J Ophthalmol 2004; 14: 478-85).

Protective role of intramuscularly administered vitamin E on the levels of lipid peroxidation and the activities of antioxidant enzymes in the lens of rats made cataractous with gamma-irradiation.

PURPOSE: To determine the antioxidant role of vitamin E (VE) (10 mg/kg/day) against radiation-induced cataract in lens after total-cranium irradiation of rats with a single dose of 5 Gy. METHODS: Sprague-Dawley rats were divided into three groups. Group 1 did not receive VE or irradiation but received both 0.1 ml physiologic saline intraperitoneally and sham irradiation (control group). Group 2 received to total cranium 5 Gy of gamma irradiation as a single dose (RT group) plus 0.1 ml physiologic saline intraperitoneally. Group 3 received irradiation to total cranium plus 10 mg/kg/day VE (RT+VE group). The rats were irradiated using a cobalt-60 teletherapy unit. Chylack's cataract classification (1) was used in this study. At the end of 10 days, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes (the activity of superoxide dismutase [SOD], glutathione peroxidase [GSH-Px]) and lipid peroxidation level (malondialdehyde [MDA]). RESULTS: While grade 1 cataract development was detectable in seven rats in the RT group, it was detectable only in two rats in the RT+VE group, whereas none of the rats in the control group exhibited any biomicroscopic change in their lenses. MDA level and GSH-Px activity in the rat lens in the RT group was significantly higher than in the control group. SOD activity in the RT group was lower than in the control group. The activity of SOD and GSH-Px enzymes was higher in the RT+VE group, but MDA level was lower in the RT+VE group when compared with the RT group. CONCLUSIONS: Vitamin E has a protective effect on radiation-induced cataract by decreasing oxidative stress.

Effect of oral zinc supplementation on agents of oropharyngeal infection in patients receiving radiotherapy for head and neck cancer.

We aimed to investigate the effect of zinc supplementation on oropharyngeal infections in immunocompromised patients. Thirty patients receiving radiotherapy for head and neck cancer received 150 mg/day zinc or placebo, orally, during radiotherapy and for a further 6 weeks. None received antibiotics during this period. Oropharyngeal samples were collected 1 day before the first course and 1 day after the last course of radiotherapy, and 1 week and 6 weeks after radiotherapy. Samples were cultured and pathogens identified using microbial diagnostic and gas chromatography methods. Coagulase-positive and -negative staphylococci, group A beta-haemolytic streptococci, Streptococcus pneumoniae, and Candida species were detected in both groups, but some infections, especially with Candida species and staphylococci, were prevented by zinc supplementation. We therefore suggest use of low-dose antibiotics and oral zinc supplementation in patients with these infections. No effects of zinc supplementation were observed on group A beta-haemolytic streptococci and Streptococcus pneumoniae, making it essential to start antimicrobial chemotherapy before radiotherapy.

Prolactin and cortisol levels during spontaneous and oxytocin induced labour and the effect of meperidine.

The effect of stress during labour on the plasma concentration of prolactin and cortisol was studied in 30 healthy multiparous women. The plasma concentrations of prolactin and cortisol were measured by radioimmunoassay during oxytocin induced labour, spontaneous labour, delivery and postpartum 24 h. The parturients were divided into three groups. The first group was given oxytocin for the induction of labour, the second group was also given oxytocin for the induction of labour and 100 mg of meperidine was administered intramuscularly for relief of pain and anxiety, and the third group was the control group with normal parturients who did not receive any medication. The prolactin levels showed a fall during labour in all the groups, but this fall was more marked in the first group where stress was evident. The concentrations of cortisol tended to increase during labour and reached a maximum at delivery in all three groups but in the meperidine group this level was significantly lower than the first and control groups. These results give further support to the hypothesis that maternal stress leads to a reduced concentration of prolactin and increased concentration of cortisol whereas relief of pain and maternal anxiety with meperidine lessens both effects.

Bicornuate uterus with a pregnancy in one half.

Bicornuate uterus is one of the important causes of female infertility. Pregnancy was observed in a patient who was 28 years old nullipara with primary infertility of 6 years and had bicornuate uterus.