Chronic chromium exposure-induced changes in testicular histoarchitecture are associated with oxidative stress: study in a non-human primate (Macaca radiata Geoffroy).
BACKGROUND
Reproductive toxicity of chromium is in dispute despite positive findings in rodents. Recently we reported epididymal toxicity of hexavalent chromium (CrVI) in bonnet monkeys and in this paper we report its testicular toxicity.


METHODS
Adult monkeys (Macaca radiata) were given drinking water containing CrVI (100, 200, 400 p.p.m.) for 6 months and testes were removed for ultrastructural and biochemical analyses.


RESULTS
CrVI treatment disrupted spermatogenesis, leading to accumulation of prematurely released spermatocytes, spermatids and uni- and multinucleate giant cells in the lumen of seminiferous tubules. Transmission electron microscopy revealed granulation of chromatin and vacuolation between acrosomal cap and manchette microtubules of elongated spermatids and in the Golgi area of round spermatids. Pachytene spermatocytes had fragmented chromatin and swollen mitochondria with collapsed cristae. Spermatocytes and spermatogonia in the basal compartment were unaffected. Macrophages containing phagocytosed sperm and dense inclusions in Sertoli cells were seen. Specific activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase and concentrations of the non-enzymatic antioxidants glutathione, vitamins A, C and E decreased, while concentrations of H(2)O(2) and hydroxyl radicals increased in the testis of chromium-treated monkeys. Withdrawal of chromium treatment for 6 months normalized spermatogenesis and the status of pro- and antioxidants in the testis.


CONCLUSIONS
CrVI disrupts spermatogenesis by inducing free radical toxicity, and supplementation of antioxidant vitamins may be beneficial to the affected subjects.
Department of Endocrinology, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India. aruldhasmm@yahoo.com
M Michael
MM
Aruldhas
S
S
Subramanian
P
P
Sekar
G
G
Vengatesh
Gowri
G
Chandrahasan
P
P
Govindarajulu
M A
MA
Akbarsha
D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D001205:Ascorbic Acid / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002843:Chromatin / Q000737:chemistry / Q000378:metabolism; D002857:Chromium / Q000737:chemistry / Q000494:pharmacology / Q000633:toxicity*; D003593:Cytoplasm / Q000378:metabolism; D005609:Free Radicals; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D005978:Glutathione / Q000737:chemistry / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology; D017665:Hydroxyl Radical; D008255:Macaca radiata; D008264:Macrophages / Q000378:metabolism; D008297:Male; D046529:Microscopy, Electron, Transmission; D009336:Necrosis; D018384:Oxidative Stress; D010587:Phagocytosis; D017382:Reactive Oxygen Species; D012708:Sertoli Cells / Q000378:metabolism; D013087:Spermatids / Q000378:metabolism; D013090:Spermatocytes / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D013737:Testis / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D013997:Time Factors; D014617:Vacuoles / Q000378:metabolism; D014801:Vitamin A / Q000378:metabolism; D014810:Vitamin E / Q000378:metabolism
D000975:Antioxidants; D002843:Chromatin; D005609:Free Radicals; D017382:Reactive Oxygen Species; D002857:Chromium; D014801:Vitamin A; D014810:Vitamin E; D017665:Hydroxyl Radical; D006861:Hydrogen Peroxide; D005954:Glucosephosphate Dehydrogenase; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005978:Glutathione; D001205:Ascorbic Acid