Chromium-induced biochemical, genotoxic and histopathologic effects in liver and kidney of goldfish, carassius auratus

Abstract

Fish constitute an excellent model to understand the mechanistic aspects of metal toxicity vis-à-vis oxidative stress in aquatic ecosystems. Hexavalent chromium (Cr (VI)), due to its redox potential can induce oxidative stress (OS) in fish and impair their health. In the present investigation, we hypothesize that OS plays a key role in chromium induced toxicity in goldfish; leading to the production of reactive oxygen species (ROS) such as O · 2 , H 2 O 2 , OH · , and subsequent modulation of the activities of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), metallothioneins (MT), glutathione proxidase (GPx), genotoxicity and histopathology. To test this hypothesis, antioxidant enzymes, DNA damage and histopathology assays were performed in liver and kidney tissues of goldfish exposed to different concentrations of Cr (VI) (LC 12.5 , LC 25 and LC 50 ) following 96h static renewal bioassay. The results of this study clearly show that the fish experienced OS as characterized by significant modulation of enzyme activities, induction of DNA damage and microscopic morphological changes in the liver and kidney. In both tissues, CAT activity was decreased whereas SOD activity and hydroperoxide levels were increased. In addition, GPx activity also increased significantly in higher test concentrations, especially in the kidney. MT induction and DNA damage were observed in both tissues in a concentration dependent manner. Microscopic examination of organ morphology indicated degeneration of liver tissue and necrosis of central vein. Necrosis of kidney tubular epithelial cells and tubules was observed at higher Cr (VI) concentrations. Taking together the findings of this study are helpful in organ-specific risk assessment of Cr (VI)-induced oxidative stress, genotoxicity and histopathology in fish.

Quality Assessment of Waterside River, Ogbor Hill Aba 4: Effect of Three-Point Samples on Hepatic Histo-Morphology and Some Seric Bio-Functional Indicators of Wistar Rats

“…Histomorphologic changes confirmed persistent toxic assault on organs in collaboration with seric chemistry results and at times as could not be detected by seric results [16,[40][41][42] . The congestion of central vein of the liver as noted in this study was consistent with hepatic response to heavy metals toxic assault in various animal models [6,7,[37][38][39]43,44] .…”

<i>IN-VIVO</i> EVALUATION OF HEXAVALENT CHROMIUM INDUCED DNA DAMAGE BY ALKALINE COMET ASSAY AND OXIDATIVE STRESS IN <i>CATLA CATLA</i>

“…After electrophoresis, the slides were washed three times with neutralization buffer (0.4M Tris, pH 7.5). All preparative steps were conducted in yellow light to prevent occurance of additional DNA damage (Avishai et al, 2003;Tice et al, 2000;Velma and Tchounwou, 2010).…”

“…Enzyme activity is expressed as superoxide dismutase units per gram of protein. One unit is defined as the amount of enzymes that inhibits the ratio of adrenochrome formation by 50% (Sun et al, 2006;Velma and Tchounwou, 2010).…”

Hekzavalent Kromun Capoeta capoeta (Guldenstaedt 1773) ve Squalius cephalus (Linnaeus 1758) Üzerine Olan Etkisinin Histopatolojik ve Elektroforetik Yöntemlerle Saptanması

“…Bununla birlikte krom toksisitesine bağlı olarak hepatositlerde atrofi ve sinozoidal boşluklarda artış gözlenmiştir [8] . Başka bir çalışmada, Kroma maruz bırakılan Japon balığı (Carassius KOÇ auratus)'larda krom maruziyeti neticesinde karaciğer dokularında dejenerasyon ve vena centraliste nekrozlar gözlemlendiği bildirilmiştir [9] . Mevcut çalışmada, 10 mg/L dozunda potasyum dikromata 10 gün süreyle maruz kalan Capoeta capoeta ve Squalius cephalus'a ait karaciğer dokularının mikroskobik incelemesinde ise fokal nekroz alanları ile birlikte vakuolar ve hidropik dejenerasyonlar tespit edildi.…”

“…Krom deri, tekstil, paslanmaz çelik, elektrokaplama gibi birçok endüstri alanında su kaynaklarına boşaltılmakta ve başta balık popülasyonları olmak üzere sucul ekosistem için oldukça ciddi tehdit oluşturmaktadır [7][8][9] . Kromun balıkların karaciğer, solungaç, böbrek gibi organları üzerine doz ve zamana bağlı olarak morfolojik olarak değişikliklere neden olduğu bilinmektedir.…”