Pentoxifylline effects on capacitation and fertility of stallion epididymal sperm

Abstract

The aims of this study were to determinate whether pentoxifylline (PTX) increases the motion parameters of fresh and frozen-thawed equine epididymal spermatozoa, to evaluate the tyrosine phosphorylation of frozen-thawed epididymal sperm in the presence of PTX and to determine whether the PTX-treatment of stallion epididymal sperm prior to freezing improves the fertility response of mares to a reduced number of spermatozoa per insemination dose. Fifty epididymis were flushed with a skim milk based extender with or without PTX. The pre-treatment with PTX enhanced the sperm motility after being harvested (P<0.05); however the freeze-thaw process did not alter the sperm kinematics between control and treated samples (P>0.05). Plasma membrane integrity did not differ between control and PTX group after recovery and after thawing (P>0.05), as observed in tyrosine phosphorylation, which the PTX treatment did not alter the percentage of tail-associated immunofluorescence of cryopreserved epididymal sperm (P>0.05). For the fertility trial, different insemination groups were tested: 800×10 epididymal sperm (C800); 100×10 epididymal sperm (C100); 100×10 epididymal sperm recovered in an extender containing PTX (PTX100). The conception rates for C800; C100 and PTX100 were 68.7% (11/16); 31.5% (5/16) and 50% (8/16), respectively. The conception rate did not differ among groups (P>0.05), however, a low number of animals was used in this study. A trend toward significance (P=0.07) was observed between C800 and C100 groups. In conclusion, PTX has no deleterious effect on sperm motility, viability and capacitation of cryopreserved stallion epididymal sperm. The conventional artificial insemination with 100×10 sperm recovered with PTX ensures acceptable conception rates and maximize the limited number of doses of cryopreserved stallion epididymal sperm.

Drosophila melanogaster Sperm under Simulated Microgravity and a Hypomagnetic Field: Motility and Cell Respiration

“…Moreover, this effect can be offset by the addition of pentoxifylline. Pentoxifylline, a phosphodiesterase inhibitor, increases cAMP concentration [ 46 , 47 ] and tyrosine phosphorylation [ 48 , 49 ]. In addition, the oral administration of essential phospholipids prevented a decrease in speed and an increase in the frequency of beating of the tail of the sperm.…”

Effect of Caffeine and Pentoxifylline Added Before or After Cooling on Sperm Characteristics of Stallion Sperm

“…Also, the addition of PT enhanced motility in cooled stallion sperm [9]. In epididymal stallion sperm, CF and PT enhanced motility and kinematic parameters [35,37], and also PT improved membrane integrity as tyrosine phosphorylation status remained unaffected [37]. Caffeine and PT seem to be more efficient in epididymal sperm than in ejaculated sperm because its ability to increase levels of cAMP appears to be more effective on quiescent sperm compared to already motile sperm [35].…”

Evaluation of pentoxifylline and Basal Medium Eagle supplemented to diluent on cryopreserved goat spermatozoa

“…Many reports demonstrate that using of specific substance such pentoxifylline improved the motion characteristics of fresh and post-thaw spermatozoa in different species, which exerts its effects probably by inhibiting cAMP-phosphodiesterase, thus TA B L E 1 Effects of pentoxifylline (PTX) and Basal Medium Eagle (BME) in diluents on motility and velocity characteristics of cryopreserved goat spermatozoa increasing the intracellular cAMP concentration (Bell et al, 1993;Duan & Goldberg, 2003;Gil et al, 2010;Guasti et al, 2013Guasti et al, , 2017Hassanpour et al, 2010;Maxwell et al, 1995;Milani et al, 2010;Mirshokraei et al, 2011;Thongtip et al, 2008). Moreover, PTX, as a phosphodiesterase inhibitor, has been postulated to cause an increase in tyrosine phosphorylation level being associated with an augmentation in spermatozoa motion and kinetic parameters, hyperactivity, acrosome reaction and conception's rate (Henkel & Schill, 2003).…”

“…Pentoxifylline (PTX), as a phosphodiesterase inhibitor in the methylxanthine group, is known to protect the spermatozoa during cryopreservation processes (Bell, Wang, Hellstrom, & Sikka, 1993; Duan & Goldberg, 2003; Gil et al., 2010; Guasti et al., 2013, 2017; Hassanpour, Mirshokraei, Tajik, & Haghparast, 2010; Maxwell et al., 1995; Milani et al., 2010; Mirshokraei, Hassanpour, Mehdizadeh, & Taheri, 2011; Thongtip et al., 2008). The suggestions above indicated that PTX stimulates the spermatozoa motion, acrosome reaction and fertilization rate by inhibition of cyclic adenosine monophosphate (Lardy, Garbers, Lust & First, 1971; Aitken, 1997; Armstrong, Clulow, Murdoch, & Jones, 1994; Yovich, 1993) which is additionally able to scavenge the ROS formation (McKinney, Lewis, & Thompson, 1996; Zhang, Sharma, Agarwal, & Falcone, 2005).…”