الفهرس 
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Abstract
Azoles are predominantly fungistatic. Azole compounds play a key role as antifungals in agriculture and in human mycoses and as non-steroidal antiestrogens in the treatment of estrogen-responsive breast tumors in postmenopausal women. They are very specific in their mode of action as they inhibit the biosynthesis of sterol, a critical component for the integrity of fungal cell membranes. These effects may be explained by inhibition of sterol 14α-demethylase and/or aromatase as well as blocking of the fungal ergosterol synthesis. Furthermore, triazole-derivative fungicides have registered or requested uses for a number of food commodities as well as registered and proposed uses for turf and ornamental plantings.
The diniconazole, a triazole derivative, is an active ingredient of the fungicide Sumi-8 that has a moderately hazardous fungicide. It may cause harm to male sexual development and fertility as inhibits animal gonads, sperm counts and adrenal steroid synthe¬sis leading to decrease the testosterone and cortical production. In general, the azole fungicides have a low acute toxicity but the knowledge about their potential health risks at low chronic exposures is very limited.
Hence, the present study was constructed to evaluate and assess the expected side effects of the Sumi-8 fungicide on the testis of the male albino mice. Accordingly, the study was devoted to determine the lethal dose (LD50) of the fungicide Sumi-8, and then applied the chosen sublethal doses orally to the mice. The chosen doses were 1/10 and 1/5 of LD¬¬50¬ of the fungicide Sumi-8 that represent 23.5 and 47 mg/kg body weight for two and four weeks respectively.
After that, the study recorded any morphological features including their body weights, histopathological, histochemical, ultrastructural abnormalities as well as sperm anomalies after orally administration of chosen doses to adult male mice.
Hence, the study illustrated the effect of such doses of the fungicide Sumi-8 on ninety adult male mice that were divided into two main groups: The first group ”A” included forty adult male mice and was chosen to determine and calculate the lethal dose (LD50) of the fungicide Sumi-8. The second group ”B” contained fifty adult male mice and was divided equally into five subgroups, each one included ten animals.
The first subgroup was considered as the control (subgroup 1) that was orally received daily 80 µl of the fungicide solvent (distilled water) for two and four weeks.
Animals of the second (subgroup 2) and third (subgroup 3) were orally administrated with the 1/10 LD50 (23.5 mg/kg) of the Sumi-8 in 80 µl for two and four weeks respectively. Animals of the fourth (subgroup 4) and fifth (subgroup 5) were also orally received the 1/5 LD50 of the Sumi-8 (47 mg/kg) in 160 µl for two and four weeks respectively.
At the end of the experiments, the animals were sacrified and then examined the testes histologicaly, histochemicaly, ultrastructurally and examination of sperm abnormalities of all subgroups (the control and treated male albino mice).
Mean body weight:
The results showed that the control male albino mice (subgroup 1) seemed to be in normal conditions in body weight gain, where the other subgroups illustrated a conspicuous decrease in their mean body weight gain after treatment with Sumi-8 fungicide. Among this trend, it was found that the maximal decrease in body weight was recorded after four weeks of treatment using different doses. This indicated that the fungicide was more effective on the body weight after long periods of administration.
However, the treated mice with the Sumi-8 did not show any external morphological malformations.
Histopathological results:
At the light microscopical level, histological examination of the testes of treated mice exhibited many histopathological changes that increasingly progressed within the augmentation in dose and time of treatment. These remarked changes elaborated in both seminiferous tubules and interstitial tissue of the testes of the treated animals compared with the control and could be summarized in the following:
i.Marked severe degenerative features of the seminiferous tubules and their spermatogenic lining cells.
Ii.Rupture of basement membrane of some seminiferous tubules.
Iii.Disattachment and disorganization of the testicular tissue causing wide spaces between tubules.
Iv.Gradual degenerative features in the testicular tissue involved mainly vacuolar degenerations and ended by necrosis of spermatogonia and primary spermatocytes being concomitance with nuclear lesions reflected as pyknosis.
V.Degenerative alternations of seminiferous tubules with maturation arrest in the late-stage spermatids with occlusions and sloughed germ cells.
Vi.Damage and hypoplasia of Leydig cells and interstitial tissue
vii.Congestion of blood vessels represented by dilation blood vessels besides the detected hemorrhagic areas in the inter-tubular spaces
Histochemical results:
In the present study, an obvious dose and time-dependent fashion between administration and severe impacts in carbohydrates, total proteins and DNA and RNA inclusions of the mice testes were detected.
Obvious decrease in the levels of glycogen, protein as well as DNA and RNA in the testes of the treated mice with Sumi-8 for two and four weeks compared with the control ones and could be summarized in the following:
i.Gradually depletion of general carbohydrates in the testicular tissues that became more obvious with the prolonged administration.
Ii.Moderate depletion of polysaccharides at basal lamina and primary spermatocytes.
Iii.Certain severe depletion of polysaccharides in spermatids and spermatozoa.
Iv.Negative PAS-reaction with Leydig and Sertoli cells.
V.Slight decrease of the total proteins in the cytoplasm and nuclei in the mice testicular tissues.
Vi.A highly depletion of the total proteins in both cytoplasm and nuclei of all testicular tissue after long periods of treatment.
Vii.Decrease in the levels of DNA and RNA.
Ultrastructural results:
At an electron micro¬scopic level, the fungicide Sumi-8 induced various alterations of the testicular tissue. These alternations could be summarized in the following:
i.The surrounding basal lamina of the tubules were thickened with irregular wavy appearance.
Ii.The nuclei of some spermatogonia revealed clumps of highly condensed nuclear material that represented signs of pyknosis.
Iii.The cytoplasm of primary spermatocytes exhibited large numbers of lysosomes and degenerated mitochondria besides dilated rough-surfaced endoplasmic reticulum.
Iv.Spermatids appeared with markedly damaged acrosomal vesicles, the mitochondria swelled with obvious condensation of their matrix and lost their cristae.
V.Some of Sertoli cells exhibited membrane-limited dense bodies assumed lysosomes, dilated rough endoplasmic reticulum, damaged mitochondria as well as intracellular vacuoles.
Vi.A marked increase in the lipid droplet amounts, large number of lysosomes and vacuoles appeared in the cytoplasm as well as the nuclei of Leydig cells were darkly stained with an ill-defined internal structure representing a sign of pyknosis.
Sperm abnormalities:
Examination of sperms that collected from epididymis indicated that the fungicide Sumi-8 induced significant increase in sperm abnormalities. These abnormalities are compared to control one, are of time-dependent feature and can be summarized in the following:
i.Sperm head abnormalities in treated mice included amorphous head, small, big, double heads and head without tail in addition to head without hook.
Ii.Sperm tail abnormalities included tail without head, divided tail and coiled tails.
Iii.Insignificant changes was recorded in short durations of two weeks administration.
Iv.Significant increase in sperm abnormalities after administration of 1/10 and 1/5 LD50 for four weeks.
In conclusion, the foregoing results referred clearly to that the fungicide Sumi-8 had produced serious pathogenic or devastating effects that appeared in the form of retardation of spermatogenesis of treated mice as illustrated by the reduction of body weight, histopathological and histochemical as well as ultrastructural alternations of the testes in treated mice. Accordingly, the severity of these lesions are increased with the increasing of the dose and the period of treatment with the fungicide Sumi-8.
Thus, azole fungicides, in general, should be used under restrict precautions to protect the human health.