The influence of ageing on the extrapineal melatonin synthetic pathway

توضیحات

ABSTRACT

Ageing affects various physiological and metabolic processes in a body and a progressive accumulation of
oxidative damage stands out as often used explanation. One of the most powerful scavenger of reactive oxygen species (ROS) in all organs is melatonin. A majority of melatonin supplied to the body via blood originates from the pineal gland. However, we have been interested in a locally produced melatonin. We have used 2.5- and 36- months-old Wistar rats. Tissues were collected and gene expression of AA-NAT and ASMT, the two key enzymes in a synthesis of melatonin, was determined in brain, liver, kidney, heart, skin, and intestine. Since melatonin can  influence antioxidant enzymes, the activity of superoxide dismutase (SOD) and catalase (CAT), and the level of GSH were measured in liver. In addition, Copper (Cu), Zinc (Zn), and Manganese (Mn) were also determined in  liver since these microelements might affect the activity of antioxidant enzymes.The expression of AA-NAT and ASMT was increased in liver and skin of old animals. A positive correlation in AA-NAT and ASMT expression was observed in liver, intestine and kidney. Moreover, the activity of CAT enzyme in liver was increased while SOD activity was decreased. SOD and CAT were probably affected by the observed decreased amount of Cu, Zn, and Mn in liver of old animals. In our model, extrapineal melatonin pathway in ageing consisted of complex interplay of locally produced melatonin, activities of SOD and CAT, and adequate presence of Cu, Zn and Mn microelements in order to defend organs against oxidative damage.

INTRODUCTION

Ageing is unstoppable, complex biological process that affects various physiological and metabolic processes in a body, resulting in a decrease of their function (Barton et al., 2016). However, ageing is not a uniform process, since different organs, tissues and cell types may age at different rates (Hamezah et al., 2017; Bonomini et al., 2010). There are a few suggested mechanisms of ageing, and progressive accumulation of oxidative damage stands out as probably the most used explanation (Flores et al., 2012). Not all organs are equally exposed to the damaging factors, such as to the reactive oxygen species (ROS), since different organs have different functions. In  that respect, liver and skin are, in general, more exposed to possible oxidative damaging factorsthan some other organs.

Year: ۲۰۱۸

Publisher : ELSEVIER

 By : Branka Popović, Milica Velimirović, Tihomir Stojković, Gavrilo Brajović, Silvio R. De Luka

File Information: English Language/ 34 Page / size: 582 KB

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سال : ۱۳۹۶

ناشر : ELSEVIER

کاری از : Branka Popović، Milica Velimirović، Tihomir Stojković، Gavrilo Brajović، سیلویو R. De Luka

اطلاعات فایل : زبان انگلیسی / ۳۴ صفحه / حجم : KB 582

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