Effects of phenol on ovarian P450arom gene expression and aromatase activity in vivo and antioxidant metabolism in common carp Cyprinus carpio

Abstract

Ovarian cyp19a mRNA expression and P450 aromatase activity were measured in vivo in common carp Cyprinus carpio exposed to phenol for 96 h. Production of reactive oxygen species (ROS) and parameters of antioxidant defense system in serum ovary and liver of this fish after long-term phenol exposure were also studied. In vivo exposure of fish to sublethal dose of phenol for 96 h caused marked attenuation of ovarian cyp19a1a gene expression and P450 aromatase activity. Production of ROS like hydrogen peroxide and hydroxyl radicals in serum, liver and ovary in fish exposed to phenol for 15 days elevated significantly from day 1 to day 7 with no further significant increase thereafter compared to their respective control values. Total superoxide dismutase (SOD) and catalase activities in serum and ovary decreased gradually and significantly from day 1 to day 4, which then increased significantly for the rest of the exposure days. Liver SOD activity seemed to be distinctly responsive to phenol. SOD activity in liver of phenol-exposed fish started to increase gradually from day 1 to 4 with no further increase thereafter. Catalase activities in all the tissues showed significant inhibition up to day 4 which then increased gradually and significantly up to day 15 of phenol exposure compared to their respective control values. From our results, it appears that sublethal dose of phenol has the endocrine disruptive potential and effect is mediated via inhibition of ovarian P450arom gene expression and aromatase activity in vivo. Sublethal dose of phenol also caused oxidative stress, and antioxidant systems are very much effective to prevent the damages caused by the generation of ROS.

Molecular Characterization and Expression of Cytochrome P450 Aromatase in Atlantic Croaker Brain: Regulation by Antioxidant Status and Nitric Oxide Synthase During Hypoxia Stress

“…Croaker were treated with NAME, NEM and an AOX systemically in the present study so they likely exerted similar effects on oAROM as we observed with bAROM. This is supported by a report that an oxidizing agent, phenol, drastically increased H 2 O 2 , a potent ROS, and hydroxyl radical (OH•, a highly reactive ROS) and reduced AROM activity and oAROM mRNA levels in carp ovaries (Das et al, 2016). Treatment of mammalian models with NEM and NO-donors, S-nitro-N-acetylpenicillamine (SNAP) and NOC18, decrease AROM activity and estradiol-17β production by ovarian follicle cells (Snyder et al, 1996;Masuda et al, 2001), and AOX treatment restored AROM activity in placental microsomes after oxidant stress (Milczarek et al, 2008).…”

The effects of feeding and starvation on antioxidant defence, fatty acid composition and lipid peroxidation in reared Oncorhynchus mykiss fry

“…It is known that SOD value can be believed to be a more reliable and expressive set of oxidative stress indicators. High SOD activity in the whole body of 28 day starved fry might be a consequence of free radicals derived from oxidation of lipids [54][55][56][57] .…”

Differential Expression of Genes Responsible for Reproduction of Male and Female Danio rerio Following Interaction Between Estrogen Receptor and Cadmium

“…The absence of effect of E2 on aromatase in adult zebrafish brain may be due to the endogenous estrogenic stimulation on aromatase expression/activities is already high because of the positive autoregulatory feedback loop driven by E2 (Callard et al 2001). Das et al, (2016) and synthetic chemicals on brain and ovarian aromatase activity and P450arom gene expression in fish. Thus, it is imperative that modulation of cyp19b expression can alter the rate of estrogen production, disturbing the local and systemic levels of estrogen, and may lead to disruption of estrogenrelated biological process i.e.…”