Reproductive Toxicology 42 (2013) 116–124 Contents lists available at ScienceDirect Reproductive Toxicology jo ur nal home p age: www. elsevier.com/locate/reprotox Markers of oxidative stress in follicular fluid of women with endometriosis and tubal infertility undergoing IVF Abhay K. Singh a , Ratna Chattopadhyay b , Baidyanath Chakravarty b , Koel Chaudhury a,∗ a School of Medical Science and Technology, Indian Institute of Technology, Kharagpur, West Bengal, India b Institute of Reproductive Medicine, Salt Lake, Kolkata, West Bengal, India a r t i c l e i n f o Article history: Received 19 August 2012 Received in revised form 8 August 2013 Accepted 16 August 2013 Available online 29 August 2013 Keywords: Oxidative stress Trace elements Endometriosis Follicular fluid In vitro fertilization (IVF) Oocyte quality Pregnancy outcome a b s t r a c t Oxidative stress and trace elements in the oocytes environment is explored in endometriosis and impact on in vitro fertilization (IVF) outcome assessed. Follicular fluid was aspirated at the time of oocyte retrieval from endometriosis (n = 200) and tubal infertility (n = 140) and the analytes measured using spectroscopy and HPLC. Increased concentration of reactive oxygen species (ROS), nitric oxide (NO), lipid peroxidation (LPO), iron, lead, cadmium and reduced levels of total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione reductase (GR), vitamins A, C, E, copper, zinc and selenium was observed compared to tubal infertility. Increased ROS and NO in endometriosis and tubal infertility associated with poor oocytes and embryo quality. Increased levels of ROS, NO, LPO, cad- mium and lead were observed in women who did not become pregnant compared to women who did. Intrafollicular zinc levels were higher in women with endometriosis who subsequently became pregnant following IVF. © 2013 Elsevier Inc. All rights reserved. 1. Introduction Endometriosis is defined as the presence of functional endome- trial glands and stroma outside the uterine cavity. Clinically, one of the major concerns about endometriosis is its tendency to cause infertility. It is suggested that altered oocyte growth and matura- tion resulting in poor embryo quality with a decreased potential to implant is one of the key causes for low in vitro fertiliza- tion (IVF) success rate in these women [1,2]. Oxidative stress is involved in the etiology of defective oocyte development [3]. Our earlier report has shown that significantly increased reactive oxy- gen species (ROS), high lipid peroxidation (LPO) and decreased total antioxidant capacity (TAC) in follicular fluid correlate with poor oocyte and embryo quality and low fertilization rate [4]. We also observed excessive ROS generation, depolarization of mitochon- drial membrane potential and significant increase in DNA damage in granulosa cells of women with endometriosis as compared with controls [5]. Follicular fluid forms the biochemical micro-environment of the oocyte before ovulation and assists in estimating the ∗ Corresponding author at: School of Medical Science and Technology, Indian Institute of Technology, Kharagpur, West Bengal 721302, India. Tel.: +91 9434341334/3222 283573; fax: +91 3222 282221. E-mail addresses: koeliitkgp@gmail.com, koel@smst.iitkgp.ernet.in (K. Chaudhury). developmental competence of female gametes [6]. It is rich in low- molecular weight metabolites that are direct or indirect regulators of oxidative stress and antioxidant production [7]. Low concen- trations of intrafollicular ROS are regarded as a promising marker for predicting IVF success [8]. It is believed that alterations in NO, a prime factor for nitrosative stress [9], can disturb oocyte mat- uration and folliculogenesis, thereby influencing oocyte quality [10]. Abnormally high concentrations of free radicals disrupt the balance between oxidants and antioxidants, promoting oxidative stress conditions [11]. In order to protect the follicles from oxida- tive insult, follicular fluid is naturally provided with an efficient antioxidant system [12] and trace elements, which are major com- ponents of antioxidant enzymes [13]. We have observed earlier that the chances of retrieving good quality oocytes increases consider- ably with higher total antioxidant capacity (TAC) levels in follicular fluid [4]. Several research groups have concluded that the oxidant– antioxidant balance in the oocytes environment can have a signifi- cant impact on IVF outcome in women with endometriosis [14–16]. However, the definitive role of trace elements in these women remains largely unknown. To test our hypothesis that a relation- ship exists between oxidative stress and trace elements in follicular fluid of infertile endometriosis women, ROS, LPO, TAC, enzymatic and non-enzymatic antioxidants, and various trace elements are evaluated. Further, the possible role of these parameters on IVF outcome is investigated. 0890-6238/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.reprotox.2013.08.005