• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4517-4525
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• 2016

Background: Sperm DNA damage is underlying aetiology of poor implantation and pregnancy rates but also affects health of offspring and may also result in denovo mutations in germ line and post fertilization. This may result in complex diseases, polygenic disorders and childhood cancers. Childhood cancer like retinoblastoma (RB) is more prevalent in developing countries and the incidence of RB has increased more than three fold in India in the last decade. Recent studies have documented increased incidence of cancers in children born to fathers who consume alcohol in excess and tobacco or who were conceived by assisted conception. The aetiology of childhood cancer and increased disease burden in these children is lin ked to oxidative stress (OS) and oxidative DNA damage( ODD) in sperm of their fathers. Though several antioxidants are in use to combat oxidative stress, the effect of majority of these formulations on DNA is not known. Yoga and meditation cause significant decline in OS and ODD and aid in regulating OS levels such that reactive oxygen speues meditated signal transduction, gene expression and several other physiological functions are not disrupted. Thus, this study aimed to analyze sperm ODD as a possible etiological factor in childhood cancer and role of simple life style interventions like yoga and meditation in significantly decreasing seminal oxidative stress and oxidative DNA damage and thereby decreasing incidence of childhood cancers. Materials and Methods: A total of 131 fathers of children with RB (non-familial sporadic heritable) and 50 controls (fathers of healthy children) were recruited at a tertiary center in India. Sperm parameters as per WHO 2010 guidelines and reactive oxygen species (ROS), DNA fragmentation index (DFI), 8-hydroxy-2'-deoxy guanosine (8-OHdG) and telomere length were estimated at day 0, and after 3 and 6 months of intervention. We also examined the compliance with yoga and meditation practice and smoking status at each follow-up. Results: 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 RB, as compared to controls and the relative mean telomere length in the sperm was shorter. Levels of ROS were significantly reduced in tobacco users (p<0.05) as well as in alcoholics (p<0.05) after intervention. DFI reduced significantly (p<0.05) after 6 months of yoga and meditation practice in all groups. The levels of oxidative DNA damage marker 8-OHdG were reduced significantly after 3 months (p<0.05) and 6 months (p<0.05) of practice. Conclusions: Our results suggest that OS and ODD DNA may contribute to the development of childhood cancer. This may be due to accumulation of oxidized mutagenic base 8OHdG, and elevated MDA levels which results in MDA dimers which are also mutagenic, aberrant methylation pattern, altered gene expression which affect cell proliferation and survival through activation of transcription factors. Increased mt DNA mutations and aberrant repair of mt and nuclear DNA due to highly truncatred DNA repair mechanisms all contribute to sperm genome hypermutability and persistant oxidative DNA damage. Oxidative stress is also associated with genome wide hypomethylation, telomere shortening and mitochondrial dysfunction leading to genome hypermutability and instability. To the best of our knowledge, this is the first study to report decline in OS and ODD and improvement in sperm DNA integrity following adoption of meditation and yoga based life style modification.This may reduce disease burden in next generation and reduce incidence of childhood cancers.

• 한국가금학회지
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• 제41권4호
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• pp.287-296
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• 2014

조류의 난포 성장은 호르몬의 작용에 따라 크기가 달라져 각각의 단계를 이루며 성장하게 된다. 난의 성숙에 관련된 유전자는 난 단백질 생산과 산란률에 밀접한 관련이 있으며, 이를 유전자 발현 측면에서 심도 있는 고찰이 필요가 있다. 본 연구는 NGS를 이용한 RNA-seq 데이터를 이용하여 유전자의 발현량과 유전자 상호 구조에 대한 분석을 실시하여 난의 발달 과정에 필요한 유전자군을 조사하였다. 본 실험에 사용된 개체는 한국 재래계 흑색계통이 사용되었고, 비교조직은 미성숙란과 성숙란의 RNA를 추출하여 유전자의 발현 양상을 살펴봄으로 난의 성숙에 필요한 유전자의 발현 양상을 보고자 하였다. 실험을 위해 Total RNA를 추출하였고, HiSeq 2000 platform을 사용하여 염기서열을 분석하고, Tuxedo Protocol과 DAVID 프로그램을 통해 유전자의 기능과 상호간의 연관관계를 예측하였다. 탐색된 유전자군은 미성숙란과 성숙란 간에 많은 차이를 보이고 있는 유전자군을 탐색한 결과, 315개의 발현이 다르게 나타나는 것으로 보이고 있으며, GO 분석을 통하여 기능면에서 미성숙란과 성숙란에서 확연히 구분되는 유전자 발현 양상을 확인할 수 있었다. 이들 결과를 통하여 향후 난성숙 과정을 이해하고, 계란 품질 향상을 위한 마커 개발을 기여할 수 있을 것으로 사료된다.