Separate and combined effects of aerobic training and vitamin D supplementation on total antioxidant capacity and malondialdehyde in prostate tissue of rats with prostate cancer

Extended Abstract
Background and Purpose
Prostate cancer (PCa) is one of the most common cancers among men. Data indicate that prostate adenocarcinoma is the most prevalent type of PCa. Factors such as age, lifestyle, genetic history, metabolic syndrome, obesity, and environmental influences appear to contribute to the development of this disease.
Regular physical activity is associated with reduced mortality from uterine and ovarian cancers, decreased mortality from PCa, and even slowing the progression of these diseases. Exercise can increase antioxidants, modulate redox balance, and regulate the expression of metabolic genes. Besides physical activity, it is believed that the use of natural antioxidants and a proper diet can have beneficial effects on some chronic diseases. One of these antioxidants is vitamin D (VD); VD is one of the most well-known nutrients with a crucial role in vital cellular mechanisms. Evidence shows that VD acts as an antioxidant by directly neutralizing free radicals and may serve as a suitable complementary agent in cancer therapies.
Systematic reviews confirm that aerobic exercise induces an adaptive antioxidant response and increases levels of SOD, CAT, and GPx, while initially raising oxidative biomarkers such as MDA in an exercise-dependent manner—but subsequently decreasing them. This hormonal effect creates an enhanced redox balance in target tissues, including the prostate. Although both vitamin D and aerobic exercise independently reduce oxidative damage in prostate tissue, their combined effects on MDA and TAC have not been fully investigated. The convergence of their mechanisms—suppressing ROS production, enhancing antioxidant enzyme systems, and reducing lipid peroxidation—indicates a potential synergistic advantage in prostate cancer. Evaluating their joint impact could reveal additive or even synergistic improvements in oxidative balance and provide insight into novel complementary interventions for prostate disease.
Methods                                                               
In this experimental study, 48 male Wistar rats were obtained from the breeding and laboratory animal center of Beitaran Laboratory. The samples were selected purposefully and based on availability. Male rats aged between 10 to 12 months and weighing between 280 to 300 grams were considered for the study. Forty rats with induced prostate cancer were randomly divided into five groups: (1) diseased control group (PCa), (2) sham group (vitamin D solvent/sesame oil, Sh), (3) vitamin D supplementation group (VD), (4) exercise group (T), and (5) exercise plus vitamin D group (T+VD). Additionally, to examine the effect of prostate cancer induction on the study variables, eight healthy rats were assigned to the healthy control group (HC).
To induce prostate cancer in the rats, LNCaP and TSP-1-EnSCs cell lines were first ordered from the Pasteur Institute of Iran under standard conditions and appropriate culture media containing all necessary nutrients for cell viability. The cells were cultured and maintained in RPMI 1640 medium supplemented with 5% fetal bovine serum (FBS) from Life Technologies, Canada. For preparing the injectable solution to the prostate gland, a suspension containing 1×10^6 LNCaP cells in 75 microliters of RPMI 1640 with 5% FBS and 75 microliters of Matrigel was prepared. The rats were anesthetized using a combination of ketamine and xylazine. A transverse incision was made in the lower abdominal cavity, and after cutting through the superficial and deep muscles, the abdominal muscles were incised, and the bladder and seminal vesicles were freed through the incision to expose the dorsal lobe of the prostate.
The prostate cancer-induced rats were familiarized with a special rotating wheel for rats and exercise protocols for one week. Subsequently, the rats ran daily for 60 minutes at a speed of 15 meters per minute on a 15-degree incline.
Vitamin D used in this study was purchased from Sigma Aldrich, USA. Due to its insolubility in non-fatty substances, vitamin D was dissolved in sesame oil and administered intraperitoneally at a dose of 1000 IU/kg daily. Malondialdehyde (MDA) and total antioxidant capacity (TAC) levels were measured using ZellBio kits from Germany.
To analyze differences between groups, paired t-tests and one-way ANOVA were applied. When significant differences were found, Tukey’s post hoc test was used to determine the location of the differences. Data analysis was performed using SPSS software version 19, and a significance level of p ≤ 0.05 was considered for all analyses.
Results
The results of the one-way ANOVA test showed significant differences in the levels of total antioxidant capacity (TAC) (P = 0.001, F = 44.41) and malondialdehyde (MDA) (P = 0.001, F = 66.87) among the study groups. Tukey’s post hoc test revealed that TAC in the prostate tissue of the prostate cancer group (PCa) was significantly lower than that of the healthy control group (HC) (P = 0.008). Although no significant differences in TAC levels were observed between the PCa group and the vitamin D supplementation group (VD) (P = 0.26) or the exercise group (T) (P = 0.12), TAC levels in the combined exercise and vitamin D group (T+VD) (P = 0.001) and the sham group (Sham) (P = 0.001) were significantly higher compared to the PCa group. Furthermore, TAC in the T+VD group was significantly higher than in the T (P = 0.001), VD (P = 0.001), and Sham (P = 0.001) groups.
Regarding MDA levels, the PCa (P = 0.001) and Sham (P = 0.001) groups exhibited significantly higher values compared to the HC group. Conversely, MDA levels in the VD (P = 0.001), T (P = 0.001), and T+VD (P = 0.001) groups were significantly lower than those in the PCa group. Additionally, the T (P = 0.003) and T+VD (P = 0.001) groups showed significantly lower MDA levels compared to the VD group. Moreover, MDA levels in the T+VD group were significantly lower than those in the T group (P = 0.001).
Conclusion                                                                                                                          
It appears that although exercise and vitamin D individually have a limited effect on reducing malondialdehyde (MDA) levels in the prostate tissue of rats with prostate cancer, their combination can enhance these effects by significantly improving antioxidant capacity and further decreasing MDA. This suggests a synergistic interaction between aerobic exercise and vitamin D supplementation, which may offer a more effective strategy to mitigate oxidative stress and lipid peroxidation associated with prostate cancer progression. Integrating both interventions could therefore provide a promising complementary approach in managing oxidative damage in prostate cancer.
Key Words: Exercise training, Vitamin D, Total antioxidant capacity, Prostate cancer
Article message
The combination of aerobic exercise and vitamin D supplementation can more effectively enhance the antioxidant capacity and reduce malondialdehyde (MDA) levels in the prostate tissue of rats with prostate cancer compared to either intervention alone; therefore, simultaneous application of these two interventions represents a more effective strategy for improving oxidative status in prostate cancer.
Ethical Considerations
This study was approved by the Ethics Committee of the University of Kurdistan under the code IR.UOK.REC.1403.049.
Authors’ Contributions
All authors contributed to the design, implementation, and writing of all parts of the present study.
Conflict of Interest
The authors declare no conflict of interest..
Acknowledgments (Times New Roman (Headings CS) 12 bold)
We thank all those who helped us in this study.