Quantitative microscopical and histochemical changes in the Liver and Testis of adult rabbit under the effect of oral intake of cotton seeds Gossypol

Abstract

Gossypol is a natural yellowish phenolic compound (dimeric or bis-naphthalene) isolated from the seeds of cotton plants (Gossypium species). The aim of the present work was to study the possible microscopical and histochemical changes in the liver and testis of adult rabbit under the effect of oral intake of cotton seeds Gossypol. Eighteen 6month age adult male rabbits were subdivided into 3 equal groups (control, experimental and recovery). The experimental and recovery groups were subjected to 1.05mg/day Gossypol suspended in olive oil intubation for 9weeks and the recovery rabbits were left 9weeks after last dose. Liver and testis paraffin sections were processed and stained with Hematoxylin and eosin stain for morphological changes. Glycosaminoglycans in the seminiferous tubules were stained by PAS technique. Studying of the nucleic DNA in the spermatogenic cells was done by Feulgen technique. Quantitative study included seminiferous tubules thickness; spermatogonia and primary spermatocytes cell areas. Also the distribution of PAS positive materials analyzed as area percent and nucleic DNA as optical density. All analysis was done by the aid of image analysis System. The study showed that liver was affected by gossypol administration. The changes appeared as distinct pinpoint foci of coagulative necrosis, vacuolar degeneration of hepatocytes and dilation of the sinusoids with mild perivascular lymphoid aggregation. The testis showed distortion loss of spermatogenic cells, Sertoli and germ organization under the effect of gossypol. Sertoli cells showed an intracellular vacuolization. Also, there were luminal multinucleated giant cells as well as a prominent DNA fragmentation in the spermatogonia nuclei. The quantitative study showed statistically significant decrease in the mean thickness of seminiferous tubules , the mean area of spermatogonia, and primary spermatocyte , mean area percent of distribution of PAS positive materials of seminiferous tubules and a significant increase in the mean optical density of nucleic DNA of spermatogonia affinity to Feulgen stain in experimental group, (p<0.001). After 9weeks recovery periods most of the morphological and quantitative changes were still present. The study concluded that gossypol has a toxic effect on the liver and testis of rabbits and their toxicity may be more prominent in humans. The study recommend restriction of uses of cotton seed oil in human uses and further study on the possible risk of uses of cattle fed on cottonseed meals.