The time course of nod-like receptor family pyrin domain containing 3 inflammasome complex expressions in the testis tissue of an experimental varicocele rat model: An experimental study


Background: Varicocele is characterized by abnormal dilation of the testicular vein, which results in hypoxia, the accumulation of reactive oxygen species, and the production of proinflammatory cytokines. It seems that a group of cytosolic receptors named nod-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome, is activated and involved in the pathogenesis of varicocele.

Objective: We aim to determine the time course of NLRP3 inflammasome expression in the testis tissue following varicocele induction.

Materials and Methods: In this experimental study, 36 adult Wistar rats (8 wk 200-250 gr) were used. For the varicocele induction, the left renal vein was partially ligated. The mRNA levels of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 were evaluated by real-time polymerase chain reaction at 1, 2, 4, 8, and 12 wk after varicocele induction.

Results: Results showed that the gene expression of NLRP3 inflammasome component including NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 did not alter during wk 1, 2, 4, and 8 after operation (p = 0.09). 12 wk after varicocele induction, gene expression levels were significantly unregulated (p = 0.02).

Conclusion: Our data provides clear evidence that varicocele stimulates inflammasome activation in the testis tissue 12 wk after the operation, and this time is required for investigating NLRP3 activity in the varicocele rat model.

Key words: Varicocele, Inflammasomes, NLRP3, Rat.

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