Effect of melatonin on reproductive function in propylthiouracil induced hypothyroidism in adult male rats.

OBJECTIVE: Thyroid hormones are essential for regulating metabolism, reproduction, and growth. Hypothyroidism is connected with lower sperm count and motility, leading to male infertility. Oxidative stress is likely to be linked to this interaction. Melatonin, being known as an oxidative scavenger, may offer a feasible treatment method for reproductive dysfunction accompanying hypothyroidism in adult male rats. The purpose of this investigation was to determine the mechanism by which melatonin treatment affected spermatogenic and steroidogenic function in an experimental model-induced hypothyroidism in adult male rats. MATERIALS AND METHODS: Twenty-one male albino adult rats weighing between 150 and 210 g were used in this experiment. Rats were split into three groups and studied for 11 weeks. The control euthyroid group, in which rats received 0.9% Sodium Chloride (NaCl) solution by intraperitoneal injection [solvent for 6-propyl 2-thouracil (PTU)], 6 days/week for 8 weeks; the PTU-induced hypothyroid group, in which chemical thyroidectomy was induced by intraperitoneal injection of PTU at a dose of 10 mg/kg body weight, 6 days/week for 8 weeks; and the melatonin-treated hypothyroid group, which received 3 mg/kg melatonin intraperitoneally daily for 21 days plasma free Triiodothyronine (T3), free Thyroxin (T4), thyroid stimulating hormone (TSH), free testosterone, Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH) and prolactin were measured. Also, semen analysis, testicular tissue malondialdehyde (MDA), and tumor necrosis factor-α (TNF-α) were accessed. RESULTS: The results indicated that melatonin significantly increased sperm viability and motility compared to the untreated PTU-induced hypothyroid group (p<0.001). Testicular MDA and TNF-α showed a significant decrease in the melatonin-treated hypothyroid group compared with the PTU-induced hypothyroid group (p<0.05). In addition, plasma testosterone levels were significantly increased, accompanied by a significant reduction of plasma prolactin levels compared to the untreated hypothyroid group (p<0.05 for both). CONCLUSIONS: Based on the study findings, melatonin could mitigate gonadal dysfunction induced by hypothyroidism by improving several components of semen analysis, such as sperm motility and sperm viability, as well as by enhancing testosterone production focusing on oxidative and inflammatory stress as the underlying mechanisms.

Randomized study of concurrent carboplatin, paclitaxel, and radiotherapy with or without prior induction chemotherapy in patients with locally advanced non-small cell lung cancer.

BACKGROUND: Multiple concepts of combined modality therapy for locally advanced inoperable non-small cell lung cancer have been investigated. These include induction chemotherapy, concomitant chemo-radiotherapy, and radiation only. To date, combined modality therapy specially the use of concomitant chemo-radiotherapy has led to promising results and was shown to be superior to radiotherapy alone in phase II studies. However the optimum chemo-therapeutic regimen to be used as well as the benefit of induction chemotherapy before concomitant chemo-radiotherapy are yet to be determined. Based on these observations, we investigated the use of paclitaxel and carboplatin concomitantly with radiotherapy and the benefit of prior two cycles induction chemotherapy. MATERIALS AND METHODS: In this trial 60 patients with locally advanced inoperable non small cell lung cancer, good performance status and minimal weight loss have been randomized into 3 groups each of 20 patients. Group A received induction 2 cycles paclitaxel (175 mg/m2) and carboplatin (AUC 6) on day 1 and 28th followed by concomitant paclitaxel (45 mg/m2) and carboplatin (AUC 2) weekly with radiotherapy. Group B received concomitant carboplatin, paclitaxel (same doses as in group A) and radiotherapy with no prior induction chemotherapy. Group C received only radiotherapy to a total dose of 60 Gy in conventional fractionation. RESULTS: A total of 60 patients were enrolled in this study between 1998 and 2000. Pretreatment characteristics, including age, gender, performance status, histological features and stage were comparable in each group. The incidence of oesophagitis was significantly higher in group A and B than in group C (p=0.023). Hematological toxicities was also significantly higher in group A & B than in group C (p=0.003). The response rate was significantly higher in group A and B than in group C (75%, 79%, and 40% respectively) (p=0.020). The time to in-field progression was significantly higher in group B as compared to group A (48% vs. 32% failure in 2 years respectively) (p=0.000). The median 2 year survival was significantly higher in group A and B than in group C (p=0.039) but no statistical difference was seen between group A and B. CONCLUSION: Combined chemo-radiotherapy resulted in better response and survival as compared to conventional radiotherapy in the treatment of locally advanced nonsmall cell lung cancer. Early initiation of radiation with concomitant chemotherapy resulted in prolonged time to infield progression. On the other hand, two cycles of induction chemotherapy did not show any significant difference regarding the response or survival. Weekly paclitaxel and carboplatin plus radiotherapy is a well tolerated regimen for outpatients with encouraging results.