Impact of yoga based lifestyle intervention on sperm oxidative DNA damage: study on fathers of non-familial sporadic heritable retinoblastoma patients

Abstract

Sperm chromatin integrity is essential for fertilization, proper embryonic development and birth of healthy offspring. Sperm is highly vulnerable to oxidative damage to both nuclear and mitochondrial DNA due to minimal cytosolic anti-oxidants. Retinoblastoma is the most common childhood malignancy where the de novo germ line mutations are mainly inherited from paternal allele. The present study is planned as a case control study on the fathers of children affected with affected with non-familial sporadic heritable retinoblastoma to see the effect of yoga based lifestyle intervention on the decline in oxidative stress and oxidative DNA damage. A case control study with 75 fathers of children affected with non-familial sporadic heritable retinoblastoma cases and 50 fathers of healthy children were enrolled as healthy controls. Study duration was 6 months. Fathers of children affected with non-familial sporadic heritable retinoblastoma were enrolled in a yoga-based lifestyle intervention programme. Semen samples were collected at base line (day 0), after 1 month, 3 months and 6 months of yoga intervention. ROS, DNA fragmentation index (DFI) and 8-hydroxy-2’-deoxyguanosine (8-OHdG) levels were estimated at base line (day 0), 1 month, 3 months and 6 months duration. ROS, DFI, 8-OHdG were also assessed in fathers of healthy children. Semen parameters were assessed as per the WHO, 2010 guidelines. The seminal mean ROS levels (p<0.05), sperm DFI (p<0.001), 8-OHdG (p<0.01) levels were significantly higher in fathers of children with non-familial sporadic heritable retinoblastoma as compared to fathers of healthy children. There was a reduction in mean DFI levels post yoga-based lifestyle intervention at 1 month (p=0.63), 3 months (p=0.046) and 6 months (p=0.032). Similarly, there was a reduction in seminal mean ROS levels at 1 month (p=0.74), 3 months (p=0.039) and 6 months (p=0.006). The levels of DNA oxidative base adduct i.e., 8-OHdG were also significantly reduced at 1 month (p=0.68), 3 months (p=0.043) and 6 months (p=0.022) with respect to its base line levels (day 0). Yoga-based simple lifestyle intervention meditation may significantly lower oxidative stress and oxidative DNA damage, and levels of mutagenic base 8-OHdG in the sperm DNA. Thus, yoga-based intervention is alternative and complementary treatment for maintaining/restoring sperm DNA integrity and hence, can reduce the prevalence of childhood cancers where poor sperm DNA integrity could be one of the reason.