Impact of Metabolic disrupting chemicals on redox homeostasis,energy sensors,receptor modulation,and hormone metabolism:A comparative account in Teleost and mammalian model organisms

Endocrine-disrupting chemicals(EDCs)may mimic the endogenous neuroendocrine and endocrine messengers and interfere with developmental,reproductive,immune,metabolic and other physiological functions.Modulation of basal metabolic rate,energy metabolism,food intake and engorgement by endocrine disruptors may lead to loss of metabolic equilibrium.EDC-induced loss of metabolic homeostasis and obesity gave rise to the concept of metabolic-disrupting chemicals(MDC)and environmental obesogens.Elevated oxidative stress,alterations in the circadian clock,and energy-sensing homeostasis are some of the major pathophysiological conditions implicated in promoting metabolic disruption.Reportedly,fish are the most vulnerable candidate due to their direct exposure to metabolic disruptors in aquatic habitats.Though limited,studies conducted using piscine models have helped to identify MDCs in the aquatic environment.Notably,the molecular mechanisms through which MDCs can negatively influence the metabolism of hormones,epigenetic alteration,gut dysbiosis,and changes in endocrine and metabolic receptor expression and functions have recently gained considerable attention.In this review,we provide an update on the impact of MDCs on the initiators,cellular mediators,and hormone receptors related to the maintenance of metabolic homeostasis,with particular emphasis on fish models.

Molecular determinants regulating the release of the egg during ovulation:Perspectives in piscine models

Reproduction in bony fish,specifically in the female teleost,encompasses well-defined stages,including growth and development,final oocyte maturation and finally ovulation-a pre-requisite for forming fertilizable female gametes.The morphological changes encountered during ovulatory response engage a multitude of endocrine,autocrine,and paracrine factors.These include gonadal steroids,growth factors,inflammatory cytokines,prostaglandins,leukotrienes and matrix metalloproteinases.In recent years,the active participation of prostaglandins and their receptors in LH-dependent ovulatory action has received much attention.Considerable evidence also supports the participation of nitric oxide/nitric oxide synthase(NO/NOS)unit in regulating meiotic maturation and ovulatory cascade.However,relatively less information is available on physiological relevance,the inter-relationship and the conjoined efforts of these molecular candidates to trigger ovulation in the fish ovary.The prime objective of the present article is to summarize the potential cross-talk between major molecular candidates downstream of LH action in the follicular layer.Besides,the intraovarian role of prostaglandin(PG)vis-`a-vis NO/NOS system on mammalian and teleost ovulatory response has been emphasised.