Induction of IL-1, in the testes of adult mice, following subcutaneous administration of turpentine

Problem: Interleukin-1 family is present in the testicular homogenates and its cellular compartments. It has been suggested that IL-1 is involved in physiological and pathological functions of the testicular tissues. In the present study we examined the effect of acute mostly localized inflammation, using turpentine, on the expression levels of testicular IL-1 system. Methods of study: Mice were subcutaneously injected with steam-distilled turpentine or saline (control). Three hours to 10 days following the injection, mice were killed and testis and spleen were homogenized and examined for interleukin (IL)-1α, IL-1β, and IL-1 receptor antagonist (IL-1ra) levels by enzyme-linked immunosorbent assay and polymerase chain reaction. Results: Subcutaneous injection of turpentine induced mice systemic inflammation, as indicated by significant increase in serum IL-1β levels, and IL-1α, IL-1β and IL-1ra in spleen homogenates. The levels of IL-1α, IL-1β and IL-1ra were significantly induced in testicular homogenates of adult mice following subcutaneous injection of turpentine. The significant induction of testicular IL-1α was detected after 3-24 hr of turpentine injection and decreased later (after 3-10 days) to levels similar to the control. However, significant induction of testicular IL-1β was detected only after 3-10 days of turpentine injection, and for testicular IL-1ra levels was detected after 3 hr to 6 days of turpentine injection, and after 10 days the levels were similar to the control. These results were also confirmed by mRNA expression of these factors. Conclusion: Our results demonstrate for the first time the distant effect of acute localized inflammation on testicular IL-1 levels. Thus, transient inflammatory response to infectious/inflammatory agents at non-testicular sites that elicit systemic IL-1 response should be considered during clinical treatment as a possible factor of male infertility.