The effect of endurance training on the level of tissue IL-6 and VEGF in mice with breast cancer

زمینه و هدف: تمرینات ورزش پتانسیلی در جهت پیشگیری از سرطان پستان دارد. هدف پژوهش حاضر بررسی اثرات پیشگیری و کمک درمانی تمرینات ورزشی بر سایتوکاین های درگیر در رگ زایی تومور سرطان پستان وابسته به گیرنده استروژن می باشد. روش بررسی: در این مطالعه مداخله ای 50 سر موش بالب سی ماده به طور تصادفی در چهار گروه قرار گرفتند. پس از آشناسازی با محیط دو گروه از موش ها به مدت 8 هفته تمرین استقامتی تداومی را انجام دادند و سپس سلول های سرطانی وابسته به استروژن (MC4-L2) به همه موش ها تزریق گردید. پس از آن یک گروه از موش های تمرین کرده و یک گروه از موش های تمرین نکرده به مدت 6 هفته، 5 روز در هفته تمرینات استقامتی را انجام دادند. حجم تومور به صورت هفتگی با کولیس دیجیتالی اندازه گیری شد. در پایان موش ها قربانی شدند و بافت تومور برداشته و سطوح سایتوکاین های اینترلوکین 6 (IL-6) و فاکتور رشد اپی تلیال عروق (VEGF) با روش الایزا اندازه گیری شد. یافته ها: بین گروه ها در میزان مقادیر IL-6 و VEGF و میزان رشد تومور تفاوت معناداری وجود داشت (001/0PP). نتیجه گیری: با توجه به افت مقادیر IL-6 و VEGF در گروه هایی که قبل از سرطانی شدن و پس از سرطانی شدن تمرینات ورزشی را انجام دادند؛ می توان گفت که تمرینات ورزشی علاوه بر نقش پیشگیرانه بسیار موثر، دارای نقش درمانی در تومورهای وابسته به گیرنده استروژن نیز می باشند

MicroRNA-206, let-7a and microRNA-21 pathways involved in the anti-angiogenesis effects of the interval exercise training and hormone therapy in breast cancer

Aims MicroRNAs (miRNAs) are the targeting signal-transduction pathways that can mediate tumorigenesis via their down and/or up-regulation. For example, miR-21 and miR-206 can effect on the tumor angiogenesis as an oncomir and a tumor suppressor, respectively. Materials and methods The present study is aimed to investigate the effects of the interval exercise training in combination with tamoxifen and/or letrozole on miR-21, miR-206 and let-7 as well as their underlying pathways in regard to tumor angiogenesis in sixty four mice with breast tumor. ELISA, immunohistochemistry, qRT-PCR assays were performed accomplish the study. Key findings The results showed that the tumor size was significantly declined in the exercise training, tamoxifen and letrozole groups compared to tumor group. Mir-206 and let-7 were up-regulated, and mir-21 expression was down-regulated in the exercise training compared to tumor group. Exercise training decreased the expression of ER-α, HIF-α, VEGF, CD31 and Ki67 in tumor tissue. The combination tamoxifen and/or letrozole with the exercise training could down-regulate the expression of ERα, miR-21, HIF-1α, TNF-α, CD31, Ki67 and VEGF, and up-regulate the expression of miR-206, PDCD-4, let-7 and IL-10 that led to reducing the angiogenesis and tumor growth. Significance Our results showed that miR-21, miR-206 and let-7a pathways may involve in the anti-angiogenesis effects of the interval exercise training with hormone therapy in mice model of breast tumor. © 2016 Elsevier Inc

Multi Directional Repeated Sprint Is a Valid and Reliable Test for Assessment of Junior Handball Players

The aim of the present study was to examine the validity and reliability of a 10 × (6 × 5 m) multi-directional repeated sprint ability test (RSM) in elite young team handball (TH) players. Participants were members of the Iranian national team ( = 20, age 16.4 ± 0.7 years, weight 82.5 ± 5.5 kg, height 184.8 ± 4.6 cm, body fat 15.4 ± 4.3%). The validity of RSM was tested against a 10 × (15 + 15 m) repeated sprint ability test (RSA), Yo-Yo Intermittent Recovery test Level 1 (Yo-Yo IR1), squat jump (SJ) and countermovement jump (CMJ). To test the reliability of RSM, the participants repeated the testing sessions of RSM and RSA 1 week later. Both RSA and RSM tests showed good to excellent reliability of the total time (TT), best time (BT), and weakest time (WT). The results of the correlation analysis showed significant inverse correlations between maximum aerobic capacity and TT in RSA ( = -0.57, ≤ 0.05) and RSM ( = -0.76, ≤ 0.01). There was also a significant inverse correlation between maximum aerobic capacity with fatigue index (FI) in RSA test ( = -0.64, ≤ 0.01) and in RSM test ( = -0.53, ≤ 0.05). BT, WT, and TT of RSA was largely-to-very largely correlated with BT ( = 0.58, ≤ 0.01), WT ( = 0.62, ≤ 0.01), and TT ( = .65, ≤ 0.01) of RSM. BT in RSM was also correlated with FI in RSM ( = 0.88, ≤ 0.01). In conclusion, based on the findings of the current study, the recently developed RSM test is a valid and reliable test and should be utilized for assessment of repeated sprint ability in handball players

Effects of exercise training together with tamoxifen in reducing mammary tumor burden in mice: Possible underlying pathway of MIR-21

Exercise training has an anti-tumor effect and can reduce tumor growth; however, the exact underlying mechanisms of its protective effects are still obscure. MicroRNA (miR)-21 is a predictor in cancer survival, and has a potential use as an indicator of therapeutic outcome in breast malignancies. Forty-eight female BALB/c mice were equally divided into six groups to investigate the effects of interval exercise training with tamoxifen on miR-21 expression and its possible assumed mechanisms in an estrogen receptor-positive breast cancer model. ELISA, immunohistochemistry, western blot, qRT-PCR assays were performed at the end of the study. Tumor size was significantly declined in exercise training and tamoxifen groups compared to tumor group (P<0.05). Expression of miR-21 was significantly down-regulated in trained and tamoxifen treated mice in comparison with tumor group (P<0.05). Exercise training was as effective as tamoxifen treatment in decreasing serum estradiol and ER-α expression (P<0.05). Exercise training and tamoxifen reduced tumor IL-6 levels, NF-kB and STAT3 expressions, and up-regulated TPM1 and PDCD4 expressions (P<0.05). Both exercise and tamoxifen had synergistic effects in reducing miR-21 and Bcl-2, and up-regulating PDCD4 expression. Results showed that interval exercise training may reduce mammary tumor burden in mice through possible underlying pathway of miR-21. © 2015 Elsevier B.V. All rights reserved