Assessment of Dimensional Changes in Submandibular Glands in Head-Neck Radiotherapy Patients by Ultrasonography.

OBJECTIVES: The present study investigated the dimensional changes in the submandibular glands following radiotherapy using ultrasonography. METHODS: Twenty-three patients planned to receive head-neck radiotherapy were included in this study. The anteroposterior, superoinferior, mediolateral length, and volumes of 46 submandibular glands were measured by ultrasonography at 3 different time periods (before radiotherapy and in the second and sixth months after the radiotherapy onset) and evaluated in terms of dimensional changes and the effect of the radiation dose on these changes. The data were statistically analyzed using repeated measures analysis of variance (ANOVA) and 2-factor repeated measures ANOVA. RESULTS: Before radiotherapy and in the second and sixth months after the radiotherapy onset, mean anteroposterior length of the submandibular glands was 32.39 ± 4.55, 30.38 ± 4.80, and 31.50 ± 3.68 mm, respectively; mean superoinferior length was 9.96 ± 1.54, 8.76 ± 1.26, and 9.08 ± 1.01 mm, respectively; mean mediolateral length was 24.66 ± 3.77, 22.03 ± 3.73, and 21.76 ± 4.01 mm, respectively; and mean volume was 4.21 ± 1.01, 3.08 ± 0.77, and 3.32 ± 0.63 cm3 , respectively. Moreover, there were significant differences in the anteroposterior (P < .01), superoinferior (P < .001), and mediolateral lengths (P < .001), as well as the volumes (P < .001) of the submandibular glands measured at the 3 different time periods. CONCLUSION: In the second and sixth months after the radiotherapy onset, the sizes of the submandibular glands were markedly reduced, but it partially recovered to normal as more time elapsed after radiotherapy.

Effects of irradiation, restoration and crown fracture type on the maximum load to fracture traumatized incisors: An ex vivo study.

BACKGROUND/AIMS: Radiotherapy makes teeth prone to tooth fractures. However, the relationship between radiotherapy and maximum load to fracture teeth that suffered a crown fracture is not fully understood. The aim of this study was to evaluate the influence of fracture type, radiation dose, fracture time, and their interactions on maximum load to fracture irradiated teeth. MATERIAL AND METHODS: A total of 140 permanent incisors were divided into two fracture type groups (uncomplicated and complicated) each of which included seven radiation dose subgroups (0, 10, 20, 30, 40, 50, and 60). The test groups were exposed to high-energy X-ray at 2 Gy/day, 5 days/week for a total dose of 10-60 Gy. Control groups were not irradiated. The load where the specimen started to break was obtained two different times. The 1st fracture was performed after radiation therapy, and the 2nd fracture was performed after the restoration of these samples. RESULTS: Fracture type had no effect on the maximum load to fracture. In contrast, the maximum load to fracture teeth decreased with increasing radiation doses. Maximum load to fracture the restored teeth was lower than the 1st fracture results. The general linear model procedure revealed a significant interaction between radiation dose and fracture time. Similarly, there was a significant interaction between the fracture type, radiotherapy dose, and fracture time. Maximum load values of teeth with complicated crown fractures restored with fiber posts and composite were not affected by radiation. CONCLUSION: Teeth that have been subjected to radiotherapy have an increased risk of fracture during dental trauma. However, restoration of the irradiated teeth with fiber posts and composite resin did not affect the maximum load required to fracture them.

Microtensile Bond Strength of Polyacid-modified Composite Resin to Irradiated Primary Molars.

AIM: This study evaluated the influence of various doses of radiotherapy on the microtensile bond strength (pTBS) of compomer resin to dentin and enamel in primary molars. MATERIALS AND METHODS: Thirty-five intact primary molars were collected and divided into seven groups. Teeth were irradiated with doses from 10 to 60 Gy, except for the control group. Compomer restorations were performed, and enamel-compomer resin beams and dentin-compomer resin beams were tested at a crosshead speed of 1 mm/min. RESULTS: No statistically significant difference was found between the irradiated tooth enamel and the control group (F = 1.1468; p = 0.194). However, statistically significant differences were evident among the dentin groups (F = 11.050; p < 0.001). CONCLUSION: Radiation may not cause a significant difference in the pTBS of compomer resin to primary tooth enamel, but appears to dose dependently decrease its bond strength to primary tooth dentin. CLINICAL SIGNIFICANCE: Radiotherapy may affect the success rate of compomer fillings in primary teeth, especially in deeper cavities with exposed dentin.

How Effective Is Radiotherapy in the Ultrasonographic Structural Characteristics of the Submandibular Glands?

Radiotherapy affects salivary glands more intensely than it does other organs, and salivary gland dysfunction can continue during or after treatment. The aim of this study was to examine structural alterations in submandibular glands through ultrasonography following head-neck radiotherapy in patients and to evaluate the impact of radiation dose on these modifications. Forty-six submandibular glands were assessed ultrasonographically for the changes in echogenicity, echotexture, and margin and the influence of the radiation dose on these changes before radiotherapy at 3 time points: the second and sixth months following starting treatment. Statistical analysis of the data was performed using a chi-square test. Significant relationship in 3 ultrasonographic structural characteristics-echogenicity, echotexture, and margin- of submandibular glands (P < .001, P < .001, and P < .001, respectively) were observed before and at the second and sixth months after radiotherapy. There was found a significant correlation between the radiation dose groups in the change of echotexture at 2 different time periods after radiotherapy (P < .001, P < .05, respectively) and in the change of margin at the second month after radiotherapy onset (P < .05). Preceding radiotherapy, submandibular glands typically exhibited hyperechoic echogenicity, homogeneous ecotextures, and regular margins. However, after radiotherapy, there was an observable transformation characterized by isoechoic/hypoechoic features, heterogeneous textures, and irregular margins. With the passage of time following radiotherapy, there was a tendency for the parenchyma structure to gradually revert to a normal state. Also, the radiation dose generally has an effect on the structural changes of the submandibular glands.

The role of melatonin in preventing radiation-induced intestinal injury.

PURPOSE: Despite the therapeutic effects of radiotherapy on tumor cells, it has potential severe adverse effects on the surrounding normal tissues. Acute or chronic intestinal adverse effects that are likely to occur in patients undergoing radiotherapy for pelvic and abdominal cancers lead to increased morbidity, significant impairment of the quality of life, and economic losses. Various biological, chemical and pharmacological agents are being tested to protect from and to treat radiation enteritis. This experimental study aimed to investigate the protective effects of melatonin against radiation-induced intestinal injury when administered before radiation exposure in rats. METHODS: In the present study, villus height and the number of villi in the ileum and jejunum of rats receiving two different doses of intraperitoneal melatonin (5 and 10 mg/kg) prior to a single fraction of radiation given at a dose of 8 Gy to the abdominal region, was evaluated by histopathological examination 3 and 7 days after radiation exposure. RESULTS: At a dose of 5 mg/kg, melatonin was found to be effective in preventing radiation-induced injury to villus height in the jejunum and the number of villi in the ileum and jejunum, and at a dose of 10 mg/kg it was also effective in preventing radiation-induced injury to villus height in the ileum. CONCLUSIONS: Melatonin is effective for the prevention of radiation-induced intestinal injury. This outcome can be considered an evidence to test melatonin in clinical trials.

Comparision of Radiochemotherapy Applications that Committing with Two Different Chemotherapies Route in Locally Advanced Lung Cancer.

OBJECTIVE: This study investigated pre- and post-treatment tumor and lymph node dimension response rates and differences between side-effect profiles in patients with locally advanced inoperable nonsmall-cell lung cancer (NSCLC) receiving radiotherapy (RT) and concurrent chemotherapy (CT). MATERIALS AND METHODS: A total of 30 inoperable patients who had not previously received RT and having a mean age of 58.73±8.65 years with sufficient hematological reserves and normal hepatic and renal functions were included in the study. Those with pleural effusion, supraventricular lymph node metastasis, and N3 lymph node involvement were excluded. Group I (n=15) received a 21-day 75 mg/m2 cisplatin (D1) and 15 mg/m2 vinorelbine (D1, D8), whereas Group II (n=15) received 45 mg/m2 paclitaxel and AUC2 carboplatin weekly. RT was administered using a linear accelerator device with the 3D conformal RT technique at 6-18 MV energy with a 1.8-2 Gy fraction for 6-7 weeks. RESULTS: Patients were randomized into Group I receiving RT and concurrent cisplatin-vinorelbine and Group II receiving weekly paclitaxel-carboplatin CT. Pre- and post-treatment tumor and lymph node dimensions significantly differed in both groups (p<0.001 and p<0.01, respectively). No significant change was observed in post-RT tumor and lymph node dimensions in terms of applied CT regimens (p>0.05). CONCLUSION: The significant response achieved with concurrent RT and CT in groups I and II in the local advanced stage of NSCLC is important for local tumor control. Responses to treatment in the group of two arms did not differ.

Bond strengths of two conventional glass-ionomer cements to irradiated and non-irradiated dentin.

This study evaluated the influence of irradiation on the dentin shear bond strength of two conventional glass ionomer cements (GICs). Thirty extracted molars were bisected in the mesio-distal direction. One-half of 20 teeth were irradiated with 60 Gy (5 days/week) for 6 weeks, and then GIC was placed on the irradiated dentin surface (Groups A1, B1). For the other halves of these tooth specimens, the GICs were first placed on their dentin surfaces and then the specimens irradiated (Groups A2, B2). The remaining 10 teeth were bisected and used as non-irradiated controls (Groups C1, C2). The GIC-dentin shear bond strengths were examined. Groups A2 and B2 had significantly lower bond strengths than groups A1, B1, C1, and C2 (p < 0.05). No significant differences were found among groups A1, B1, C1, and C2 (p > 0.05). In conclusion, irradiation may have an adverse effect on the bond strength of GICs depending on the application sequence.

Carnitine and Adiponectin Levels in Breast Cancer after Radiotherapy.

In this study, serum carnitine (CRNT) and adiponectin (APN) levels and the correlation of these parameters in patients with breast cancer before and after treatment with radiotherapy (RT) were determined. MATERIALS AND METHODS: Serum adiponectin and carnitine levels were assessed in 58 patients with breast carcinoma and 30 control subjects. Serum carnitine and APN levels were determined using a specific enzyme-linked immunosorbent assay. RESULTS: While serum carnitine level was significantly lower in the patients with breast cancer after RT compared with the control group and before treatment (p=0.002 and p=0.019, respectively), serum APN level was significantly higher than in the control group and before treatment ( p=0.003 and p=0.027, respectively). Carnitine level showed a negative correlation with APN level in the patients after RT (r= -0.626, p= 0.001). There was no correlation between carnitine and APN levels in subjects of control group and before treatment. Also, neither carnitine nor APN levels demonstrated correlation other parameters. CONCLUSIONS: Results suggest that increased serum adiponectin and decreased carnitine levels in breast cancer after RT than control group. Carnitine level showed a negative correlation with APN level in the patient with breast cancer after RT. While carnitine, HDL-C and total cholesterol levels are decreased, trygliceride and LDL-C levels are increased in patients than control group. In addition, serum APN concentration was inversely correlated with serum carnitine levels. Furthermore, increased serum APN level in breast cancer after RT might be associated with hypocarnitinemia.

Zinc Sulfate and/or Growth Hormone Administration for the Prevention of Radiation-Induced Dermatitis: a Placebo-Controlled Rat Model Study.

Growth hormone (GH) and zinc (Zn) were evaluated for their potential to prevent radiation injury using a rat model of radiation-induced skin injury. Sprague-Dawley rats were divided into five groups: a control group not receiving Zn, GH, or irradiation: a radiation (RT) group receiving a single 30 Gy dose of gamma irradiation to the right hind legs; a radiation + GH group (RT + GH) receiving a single 30 Gy dose of gamma irradiation plus the subcutaneous administration of 0.01 IU kg d-1 GH; a radiation + Zn group (RT + Zn) receiving a single 30 Gy dose plus 5 mg kg d-1 Zn po; and a radiation + GH + Zn group (RT + GH + Zn) group receiving a single 30 Gy dose plus subcutaneous 0.01 IU kg d-1 GH and 5 mg kg d-1 Zn po. Acute skin reactions were assessed every 3 days by two radiation oncologists grouping. Light microscopic findings were assessed blindly by two pathologists. Groups receiving irradiation were associated with dermatitis as compared to the control group (P < 0.05). The severity of radiodermatitis in the RT + GH, RT + Zn, and RT + GH + Zn groups was significantly lower than that in the RT group (P < 0.05). Furthermore, radiodermatitis was observed earlier in the RT group than in the other treatment groups (P < 0.05). GH and Zn effectively prevented epidermal atrophy, dermal degeneration, and hair follicle atrophy. The highest level of protection against radiation dermatitis was observed in the combination group.

Vitamin E and L-carnitine, separately or in combination, in the prevention of radiation-induced oral mucositis and myelosuppression: a controlled study in a rat model.

The aim of this study was to determine the effects of vitamin E (VE) and L-carnitine (LC) supplementation, separately or in combination, on radiation-induced oral mucositis and myelosuppression. Group 1 received no treatment (control). Group 2 received 15 Gray of 60Co gamma irradiation as a single dose to total cranium (IR). Group 3, 4, and 5 received irradiation plus 40 mg/kg/day VE (IR+VE) or 200 mg/kg/day LC (IR+LC) or in combination (IR+VE+LC) respectively. Clinically and histopathologically, assessments of mucosal reactions were performed by two independent experts in Radiation Oncology and Pathology, respectively. Hematologic analyses and antioxidant enzyme evaluations were also performed. Irradiation significantly increased oral mucositis, and decreased thrombocyte and White Blood Cell counts. A significant increase in malondialdehyde (MDA) levels and decrease in superoxide dismutase (SOD) and catalase (CAT) activities in plasma were found in the IR group. VE and LC administration, separately, plus irradiation significantly delayed the starting day, and reduced the severity of, oral mucositis. This administration also reduced a fall in the numbers of thrombocyte and WBC caused by irradiation, and decreased the MDA level, and increased the activity of SOD and CAT enzymes in the plasma. VE and LC, in combination, plus irradiation did not provide a superior radioprotection against radiation-induced toxicities.

Radioprotective effects of melatonin on radiation-induced cataract.

One of the mechanisms proposed to explain lens opacification is the oxidation of crystallins, either by radiation or reactive oxygen species (ROS). It has been shown that melatonin has both an anti-peroxidative effect on several tissues and a scavenger effect on ROS. The purpose of this study was to determine the antioxidant role of melatonin (5 mg/kg/day) against radiation-induced cataract in the lens after total-cranium irradiation of rats with a single dose of 5 Gy. Sprague-Dawley rats were divided into four groups. Control group received neither melatonin nor irradiation. Irradiated rats (IR) and melatonin+irradiated rats (IR+Mel) groups were exposed to total cranium irradiation of 5 Gy in a single dose by using a cobalt-60 teletherapy unit. IR+Mel and melatonin (Mel) groups were administered 5 mg/kg melatonin daily by intraperitoneal injections during ten days. Chylack's cataract classification was used in this study. At the end of the 10th day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes i.e. the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and lipid peroxidation level (malondialdehyde (MDA)). Irradiation significantly increased the MDA level, as an end product of lipid peroxidation, and also significantly decreased SOD and GSH-Px activity, emphasizing the generation of increased oxidative stress. Rats injected with melatonin only did not cause cataract formation. Melatonin supplementation with irradiation significantly increased the activity of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose enhanced cataract formation, and melatonin supplementation protected the lenses from radiation-induced cataract formation. Our results suggest that supplementing cancer patients with adjuvant therapy of melatonin may reduce patients suffering from toxic therapeutic regimens such as chemotherapy and/or radiotherapy and may provide an alleviation of the symptoms due to radiation-induced organ injuries.

Zinc sulfate in the prevention of radiation-induced oropharyngeal mucositis: a prospective, placebo-controlled, randomized study.

PURPOSE: To determine the effect of oral zinc sulphate supplementation on radiation-induced oropharyngeal mucositis in patients with head-and-neck cancer. MATERIALS AND METHODS: Thirty patients with head-and-neck cancer were randomly assigned to receive either zinc sulfate or placebo. Primary tumors were localized in the larynx in 14 patients, in the nasopharynx in 4, in the oral cavity in 4, in a salivary gland in 1, in the maxillary sinus in 1, in neck nodes (lymphoma presenting primarily) in 3 and in neck metastases from an unknown primary in 3. In the placebo group, 3 patients were excluded; 1 patient died during treatment, 1 left the study, and 1 did not come to the 6 week control visit. The patients were treated with telecobalt radiotherapy at conventional fractionation (2 Gy/fraction, five fractions weekly, for 20-35 fractions within 4-7 weeks). The median radiation dose was 6400 cGy (4000-7000 cGy). Oral mucositis was assessed by two independent physicians, experts in radiation oncology, using the Radiation Therapy Oncology Group Acute Radiation Morbidity Scoring criteria. RESULTS: In the zinc sulfate group, Grade 3-4 mucositis was not detected in any patient; Grade 0 mucositis was detected in 2, and Grade 1 in 8, and Grade 2 in 5 patients. In the placebo group, Grade 2 mucositis was detected in 4 and Grade 3 in 8 patients. We observed that the degree of mucositis in the patients in the zinc sulfate group was significantly lower than that in the placebo group (p < 0.05). Confluent mucositis developed earlier in the placebo group than in the zinc sulfate group after the onset of treatment (p < 0.05) and started to improve sooner in the zinc sulfate group than in the placebo group (p < 0.05). CONCLUSIONS: Zinc sulfate is beneficial in decreasing the severity of radiation-induced mucositis and oral discomfort. These results should be confirmed by additional evaluation in randomized studies with a larger number of patients.

The effect of zinc sulphate in the prevention of radiation-induced dermatitis.

There is currently substantial clinical interest in zinc (Zn) as a protective agent against radiation-related normal tissue injury. To further assess this drug's potential, the effect of Zn was studied in rats using a radiation-induced skin injury model. Sprague-Dawley rats were divided into four groups. Group 1 received neither Zn nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (RT Group). Groups 3 and 4 received the same irradiation plus 5 mg/kg/day Zn (RT+5 Zn group) or 10 mg/kg/day Zn orally (RT+10 Zn group), respectively. The rats were irradiated using a cobalt-60 teletherapy unit. Acute skin reactions were assessed every three days by two independent radiation oncology experts. At the endpoint of the study, light-microscopic findings were assessed by two independent expert pathology physicians. Clinically and histopathologically, irradiation increased dermatitis when compared with the control group (p < 0.05). The severity of radiodermatitis of the rats in the RT+5 Zn and RT+10 Zn groups was significantly lower than in the RT group (p < 0.05); radiodermatitis was seen earlier in the RT group than in the other groups (p < 0.05). Zn was found to be efficacious in preventing epidermal atrophy, dermal degeneration such as edema and collagen fiber loss, and hair follicle atrophy. The most protection for radiation dermatitis was observed in the RT+10 Zn group. It would be worthwhile studying the effects of zinc sulphate supplements in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity.

Zinc sulfate in the prevention of total-body irradiation-induced early hematopoietic toxicity: a controlled study in a rat model.

Exposure to ionizing total-body radiation suppresses hematopoiesis, resulting in decreased production of blood cells. Many researchers have demonstrated the critical role of zinc (Zn) in diverse physiological processes, such as growth and development, maintenance and priming of the immune system, and tissue repair. The aim of the present study was to determine the effects of zinc sulfate (40 mg/kg and 80 mg/kg) on early hematopoietic toxicity, caused by total-body irradiation (TBI) of rats with a single dose of 8 Gy. Both in the Zn 40 and in the Zn 80 groups, there were significantly increased white blood cell (WBC) count, when compared with control group. The WBC count was higher in the control group than in the TBI group. This result was statistically significant (p<0.05). Both the TBI+Zn 40 and the TBI+Zn 80 groups had a significantly protected WBC count against TBI. No difference was detected in any final measurement of thrombocyte count and hemoglobin level with direct comparison among all groups, with the exception that the hemoglobin level in the Zn 80 group compared to the control group. Whereas hemoglobin level in the control group was at a median figure of 13.98 g/dL (13.30-14.80), it was at a median figure of 14.25 g/dL (14.10-15.50) in the Zn 80 group. It would be worthwhile studying the effect of oral zinc sulfate supplements in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity.

Effects of oral Ginkgo biloba supplementation on cataract formation and oxidative stress occurring in lenses of rats exposed to total cranium radiotherapy.

PURPOSE: To determine the antioxidant role of Ginkgo biloba (GB) in preventing radiation-induced cataracts in the lens after total-cranium irradiation of rats with a single radiation dose of 5 Gy. METHODS: Sprague-Dawley rats were randomly divided into three groups. Group 1 received neither GB nor irradiation (control group). Group 2 was exposed to total-cranium irradiation of 5 Gy in a single dose [radiation therapy (RT) Group], and group 3 received total cranium irradiation from a cobalt-60 teletherapy unit, plus 40 mg/kg per day GB (RT+GB group). At the end of the tenth day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the lipid peroxidation level [malondialdehyde (MDA)]. RESULTS: Irradiation significantly increased both the MDA level and the activity of GSH-Px, and significantly decreased the activity of SOD in the rat lenses. GB supplementation significantly increased the activities of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose promoted cataract formation, and GB supplementation protected the lenses from radiation-induced cataracts. CONCLUSIONS: We suggest that Ginkgo biloba is an antioxidant that protects the rat lens from radiation-induced cataracts.

Clinicopathological Characteristics of Triple-negative Breast Cancers in the Northeast Region of Turkey.

BACKGROUND: Triple-negative (TN) breast cancer is a subtype of breast cancer characterised by a loss of estrogen receptor (ER), progesterone receptor (PR) expression, and the absence of human epidermal growth factor (HER2) overexpression. AIMS: To identify the relationships between clinicopathological characteristics of TN breast cancers in the northeast region of Turkey and disease free survival (DFS) and overall survival (OS). STUDY DESIGN: Retrospective clinical study. METHODS: Seven hundred and eighty non-metastatic breast cancer patients were enrolled in this study. The relationships between TN breast cancer and other breast cancers with respect to clinicopathological characteristics, as well as DFS and OS, were studied. RESULTS: The triple-negative phenotype was detected in 204 patients (27.1%). Patients with triple-negative breast cancer had more grade 2-3 tumours compared to those with other types of breast cancer (92.5% versus 84.3%, p=0.004). Invasive ductal carcinoma histology, on the other hand, was less prevalent in patients with TN breast cancer (77% versus 84.5%, p=0.016). No significant differences were identified between the groups in other clinicopathological variables. Relapse and mortality rates were higher in the TN group during the follow-up of both groups [57 (27.9%) versus 89 (16.2%), p<0.001 for relapse; 27 (13.2%) versus 37 (6.8%), p=0.005 for mortality]. The univariate analysis demonstrated shorter DFS and OS for patients with TN breast cancer compared to those with other types of breast cancer. In the multivariate analysis, patients with TN breast cancer were 2.21 times more likely to develop relapse, while the likelihood of death increased 3.21-fold (p<0.001 and p<0.001). CONCLUSION: Triple-negative breast cancers demonstrate a more aggressive clinical course compared to other breast cancers. More effective strategies should be developed for the treatment of this subgroup of breast cancer.

Vitamin E and L-carnitine, separately or in combination, in the prevention of radiation-induced brain and retinal damages.

Our aim was to determine the effects of vitamin E and L-carnitine supplementation, individually or in combination, on radiation-induced brain and retinal damages in a rat model. Group 1 received no treatment (control arm). Group 2 received a total dose of 15 Gy external radiotherapy (RT) to whole brain by Cobalt-60 teletherapy machine. Groups 3, 4, and 5 received irradiation plus 40 kg(-1) day(-1) Vitamin E or 200 mg kg(-1)day(-1) L-carnitine alone or in combination. Brain and retinal damages were histopathologically evaluated by two independent pathologists. Antioxidant enzyme levels were also measured. Radiation significantly increased brain and retinal damages. A significant increase in malondialdehyde levels as well as a decrease in superoxide dismutase and catalase enzymes in brain was found in group 2. Separate administration of Vitamin E+RT and L-carnitine+RT significantly reduced the severity of brain and retinal damages and decreased the malondialdehyde levels and increased the activity of superoxide dismutase and catalase enzymes in the brain. The findings of current study support the antioxidant and radioprotective roles of vitamin E and L-carnitine. However, the combined use of Vitamin E and L-carnitine plus irradiation interestingly did not exhibit an additive radioprotective effect.

The effect of L-carnitine in the prevention of ionizing radiation-induced cataracts: a rat model.

BACKGROUND: The objective was to determine the antioxidant role of L-carnitine (LC) against ionizing radiation-induced cataracts in lens after total cranium irradiation of rats with a single dose of 5 Gy. METHODS: Sprague-Dawley rats were used in this experiment and were divided into three groups. Group 1 did not receive LC or irradiation (control group). Group 2 received a 5 Gy gamma irradiation as a single dose to the total cranium (RT group). Group 3 received total cranium irradiation plus 100 mg/kg body weight/day LC (RT+LC group). The rats were irradiated using a cobalt-60 teletherapy unit. At the end of the 10th day, the rats were sacrificed and their eyes were enucleated. The lenticular activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured. Furthermore, the lenticular content of an indicator of lipid peroxidation, malondialdehyde (MDA), was measured. RESULTS: Irradiation significantly increased the MDA level as an end product of lipid peroxidation. Irradiation also significantly decreased SOD activity and increased GSH-Px activity, indicating the generation of oxidative stress and an early protective response to oxidative damage. Irradiation with 5 Gy to the total cranium as a single fraction formed cataracts in the rat lenses. Cataract development was detectable in 9 rats in the RT group, and in only 4 rats in the RT+LC group 10 days after irradiation. LC administration plus irradiation significantly decreased the MDA level and increased the activity of SOD and GSH-Px enzymes, which might indicate the protection of the lenses from gamma radiation-induced cataracts. CONCLUSIONS: L-carnitine may protect against the damage produced by gamma radiation by increasing the activity of the SOD enzyme and by scavenging free radicals generated by ionizing radiation. As a result of this process, MDA as an indicator of lipid peroxidation may decrease.

Levels of some acute-phase proteins in the serum of patients with cancer during radiotherapy.

The acute phase response involves changes in serum concentrations of a number of liver-synthesized proteins. Among these are C-reactive protein (CRP), ferritin (FER), transferrin (Trf) and ceruloplasmin (Cp). Determination of serum CRP, FER, Trf, and Cp was performed in 52 patients with inoperable head and neck cancer (n=11), inoperable esophageal cancer (n=10), rectal cancer (n=9; operation was performed=5, inoperable=4), and lung cancer (n=22), all of whom were treated with radical radiotherapy (RT). Post-radiotherapy CRP levels were significantly higher compared to the preradiotherapy levels (p<0.001). We found decreased serum Trf levels during the irradiation period, while acute-phase proteins such as CRP, FER, and Cp levels increased during the RT period. Further studies on the roles of other acute phase reactants and the above mentioned parameters in a large-patients-with cancer group during radiotherapy are required to understand the role of markers, which are altered during radiotherapy.