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An Overview of Seasonal Changes in Oxidative Stress and Antioxidant Defence Parameters in Some Invertebrate and Vertebrate Species.

Chainy GB, Paital B, Dandapat J - Scientifica (Cairo) (2016)

Bottom Line: Antioxidant defence system, a highly conserved biochemical mechanism, protects organisms from harmful effects of reactive oxygen species (ROS), a by-product of metabolism.In this paper, we have compiled information available in the literature on seasonal variation in antioxidant defence system in various species of invertebrates and vertebrates.The primary objective was to understand the relationship between varied biological phenomena seen in different animal species and conserved antioxidant defence system with respect to seasons.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology, Utkal University, Bhubaneswar 751004, India.

ABSTRACT
Antioxidant defence system, a highly conserved biochemical mechanism, protects organisms from harmful effects of reactive oxygen species (ROS), a by-product of metabolism. Both invertebrates and vertebrates are unable to modify environmental physical factors such as photoperiod, temperature, salinity, humidity, oxygen content, and food availability as per their requirement. Therefore, they have evolved mechanisms to modulate their metabolic pathways to cope their physiology with changing environmental challenges for survival. Antioxidant defences are one of such biochemical mechanisms. At low concentration, ROS regulates several physiological processes, whereas at higher concentration they are toxic to organisms because they impair cellular functions by oxidizing biomolecules. Seasonal changes in antioxidant defences make species able to maintain their correct ROS titre to take various physiological functions such as hibernation, aestivation, migration, and reproduction against changing environmental physical parameters. In this paper, we have compiled information available in the literature on seasonal variation in antioxidant defence system in various species of invertebrates and vertebrates. The primary objective was to understand the relationship between varied biological phenomena seen in different animal species and conserved antioxidant defence system with respect to seasons.

No MeSH data available.


Related in: MedlinePlus

Schematic representation of cellular production of ROS, their impact on biomolecules, and their metabolism by antioxidant enzymes. SOD, superoxide dismutase; CAT, catalase; GPX, glutathione peroxidase; GR, glutathione reductase; O2•−, superoxide radicals; GSH, reduced glutathione; GSSG, oxidized glutathione.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4834391&req=5

fig1: Schematic representation of cellular production of ROS, their impact on biomolecules, and their metabolism by antioxidant enzymes. SOD, superoxide dismutase; CAT, catalase; GPX, glutathione peroxidase; GR, glutathione reductase; O2•−, superoxide radicals; GSH, reduced glutathione; GSSG, oxidized glutathione.

Mentions: Antioxidant defence system comprises both enzymatic and nonenzymatic components. Enzymatic system contains a cascade of enzymes which are together known as antioxidant enzymes (AOE). Antioxidant enzymes are ubiquitous and highly conserved in their catalytic nature. Some of them are present in multiple forms. The first member of this cascade is superoxide dismutase (SOD) which dismutates O2•− to H2O2. Hydrogen peroxide is neutralized by two enzymes. One of them is catalase (CAT) and the other one is glutathione peroxidase (GPx) [17]. Catalase breaks down H2O2 to oxygen and water, whereas GPx reduces H2O2 and organic hydroperoxides by coupling them with oxidation of reduced glutathione (GSH). Glutathione reductase (GR) plays a major role in generating reduced glutathione from oxidized glutathione by oxidizing NADPH. Subsequently, NADPH is generated from NADP by the enzyme glucose-6-phosphate dehydrogenase (G6PDH) (Figure 1). SOD is of three types depending upon the prosthetic group they carry. They are Fe-SOD, Mn-SOD, and Cu-Zn SOD. Fe-SOD is usually found in bacteria. Cu-Zn SOD is mainly found in the cytoplasm, whereas Mn-SOD is exclusively mitochondrial in nature. Besides, another type of Cu-Zn SOD is reported in extracellular space and is known as EC-SOD [17]. GPx has several isoenzyme forms. GPx primarily functions to detoxify low levels of H2O2 in cells, whereas CAT assumes more significance in protecting against severe oxidant stress [18]. Nonenzymatic defence system comprises small organic molecules that scavenge various ROS. They are polyphenols, ascorbic acid, tocopherol, carotenoids, reduced glutathione, and so forth [17].


An Overview of Seasonal Changes in Oxidative Stress and Antioxidant Defence Parameters in Some Invertebrate and Vertebrate Species.

Chainy GB, Paital B, Dandapat J - Scientifica (Cairo) (2016)

Schematic representation of cellular production of ROS, their impact on biomolecules, and their metabolism by antioxidant enzymes. SOD, superoxide dismutase; CAT, catalase; GPX, glutathione peroxidase; GR, glutathione reductase; O2•−, superoxide radicals; GSH, reduced glutathione; GSSG, oxidized glutathione.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4834391&req=5

fig1: Schematic representation of cellular production of ROS, their impact on biomolecules, and their metabolism by antioxidant enzymes. SOD, superoxide dismutase; CAT, catalase; GPX, glutathione peroxidase; GR, glutathione reductase; O2•−, superoxide radicals; GSH, reduced glutathione; GSSG, oxidized glutathione.
Mentions: Antioxidant defence system comprises both enzymatic and nonenzymatic components. Enzymatic system contains a cascade of enzymes which are together known as antioxidant enzymes (AOE). Antioxidant enzymes are ubiquitous and highly conserved in their catalytic nature. Some of them are present in multiple forms. The first member of this cascade is superoxide dismutase (SOD) which dismutates O2•− to H2O2. Hydrogen peroxide is neutralized by two enzymes. One of them is catalase (CAT) and the other one is glutathione peroxidase (GPx) [17]. Catalase breaks down H2O2 to oxygen and water, whereas GPx reduces H2O2 and organic hydroperoxides by coupling them with oxidation of reduced glutathione (GSH). Glutathione reductase (GR) plays a major role in generating reduced glutathione from oxidized glutathione by oxidizing NADPH. Subsequently, NADPH is generated from NADP by the enzyme glucose-6-phosphate dehydrogenase (G6PDH) (Figure 1). SOD is of three types depending upon the prosthetic group they carry. They are Fe-SOD, Mn-SOD, and Cu-Zn SOD. Fe-SOD is usually found in bacteria. Cu-Zn SOD is mainly found in the cytoplasm, whereas Mn-SOD is exclusively mitochondrial in nature. Besides, another type of Cu-Zn SOD is reported in extracellular space and is known as EC-SOD [17]. GPx has several isoenzyme forms. GPx primarily functions to detoxify low levels of H2O2 in cells, whereas CAT assumes more significance in protecting against severe oxidant stress [18]. Nonenzymatic defence system comprises small organic molecules that scavenge various ROS. They are polyphenols, ascorbic acid, tocopherol, carotenoids, reduced glutathione, and so forth [17].

Bottom Line: Antioxidant defence system, a highly conserved biochemical mechanism, protects organisms from harmful effects of reactive oxygen species (ROS), a by-product of metabolism.In this paper, we have compiled information available in the literature on seasonal variation in antioxidant defence system in various species of invertebrates and vertebrates.The primary objective was to understand the relationship between varied biological phenomena seen in different animal species and conserved antioxidant defence system with respect to seasons.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology, Utkal University, Bhubaneswar 751004, India.

ABSTRACT
Antioxidant defence system, a highly conserved biochemical mechanism, protects organisms from harmful effects of reactive oxygen species (ROS), a by-product of metabolism. Both invertebrates and vertebrates are unable to modify environmental physical factors such as photoperiod, temperature, salinity, humidity, oxygen content, and food availability as per their requirement. Therefore, they have evolved mechanisms to modulate their metabolic pathways to cope their physiology with changing environmental challenges for survival. Antioxidant defences are one of such biochemical mechanisms. At low concentration, ROS regulates several physiological processes, whereas at higher concentration they are toxic to organisms because they impair cellular functions by oxidizing biomolecules. Seasonal changes in antioxidant defences make species able to maintain their correct ROS titre to take various physiological functions such as hibernation, aestivation, migration, and reproduction against changing environmental physical parameters. In this paper, we have compiled information available in the literature on seasonal variation in antioxidant defence system in various species of invertebrates and vertebrates. The primary objective was to understand the relationship between varied biological phenomena seen in different animal species and conserved antioxidant defence system with respect to seasons.

No MeSH data available.


Related in: MedlinePlus