Suppression of CD73, GRP78 and β-catenin in the testicular interstitium during severe cerebral hypoperfusion and drug reversion

Brain lesions (trauma, stroke, hypoperfusion) are accompanied not only by neurological disorders but also by endocrine deficiency, including hypoandrogenism. Our study aims to evaluate the state of the CD73, GRP78, and β-catenin signaling pathways during atrophic processes in the testes that arise against the background of brain lesions and during pharmacological correction. Alterations in the endocrine apparatus of the testes under conditions of cerebral hypoperfusion (bilateral common carotid artery occlusion) in rats and their correction with clomiphene and/or metformin at the recovery stage (from day 15 to day 56 after bilateral common carotid artery occlusion) were investigated based on the expression of β-catenin, CD73, and GRP78, semiquantitative assessment, and statistical analysis. It has been demonstrated that in the interstitial cells of the testes of intact rats (predominantly in Leydig cells), a high expression of the CD73 marker, a distinct expression of GRP78, and a moderate to high expression of β-catenin were recorded. The administration of clomiphene to intact rats (for 42 days) led to a more than twofold increase in the expression of CD73, GRP78, and β-catenin. Under these conditions, metformin caused a slight but significant decrease in the expression of CD73 and GRP78. Following bilateral common carotid artery occlusion, a progressive decrease in the expression of all investigated markers occurred: after 56 days, the levels of β-catenin and GRP78 decreased by more than 33 percent, and the level of CD73 decreased by 22 percent compared to intact rats. In rats after bilateral common carotid artery occlusion, clomiphene induced an increase in all markers: the expression of CD73 and GRP78 after 56 days of the experiment exceeded the values of the control group (GRP78 by as much as 22 percent), and a pronounced increase in the expression of β-catenin (by 19 percent) was also recorded. In animals after bilateral common carotid artery occlusion, metformin stabilized the expression of CD73 at a level significantly higher compared to the untreated group, but it did not affect the changes in the GRP78 and β-catenin parameters. The combined effect of clomiphene and metformin (both in intact rats and in rats after bilateral common carotid artery occlusion) substantially diminished the growth rates of CD73, GRP78, and β-catenin expression compared to the effect of clomiphene alone. Thus, we have established that cerebral hypoperfusion is accompanied by a critical depletion of the purinergic regulation system (CD73 expression) in the interstitial cells of rat testes, endoplasmic reticulum dysfunction (decreased GRP78 expression), and suppression of the Wnt/β-catenin pathway regulating synthetic processes and progenitor cell development (β-catenin). The effective reinstatement of CD73, GRP78, and β-catenin expression in testicular interstitial cells by clomiphene demonstrates the recovery of testicular endocrine function after significant ischemic brain injuries.