Late reproductive analysis in rat male offspring exposed to nicotine during pregnancy and lactation

Abstract

SUMMARYWe previously observed that nicotine, administered to rats (Wistar) during pregnancy and lactation periods, provokes, in the progeny, late morphofunctional alterations in Leydig cell, body weight increase in adulthood (90 days post partum, dpp) as well as seminiferous epithelium injury. Aiming to investigate whether the spermatogenic damage previously observed in adult progenies from pregnant and lactating nicotine-exposed rat dams are maintained or whether it is worsened in older rats, we analyzed the morphological testicular alterations after up to two complete periods of spermatogenesis (53 days each), spermatic parameters, and sperm DNA fragmentation. Pregnant and lactating rats were nicotine-exposed (2 mg/kg/day) through an osmotic minipump implanted on the first day of pregnancy and replaced after birth. Absolute Control (no minipump) and Sham Control (minipump without nicotine) groups were established. The offspring were killed at 90, 143, and 196 dpp. Significant alterations in morphometric and stereological testicular parameters, such as concentration of sperm number, daily sperm production, and plasma and intratesticular levels of cholesterol and testosterone were not observed in nicotine-exposed rats. Testicular histopathological analysis showed small intraepithelial vacuolization and an accentuated germ cell desquamation in exposed rats. However, the offspring from nicotine-exposed dams exhibited higher frequency of morphologically abnormal spermatozoa and lower sperm motility in comparison with control groups. In addition, nicotine-exposed groups showed a significant reduction in sperm mitochondrial activity and an increased sperm DNA fragmentation (Comet assay). These results indicate a late reproductive damage in the male progeny caused by maternal nicotine exposure, related to the decrease in sperm quality.

Resveratrol attenuates reproductive alterations in type 1 diabetes‐induced rats

“…; Miranda‐Spooner et al . ). For this, 50 μL of the sample collected from the left epididymis of each animal ( n = 7/group) was added to solution containing 1 mg/mL of DAB in phosphate buffer solution (PBS; 137 mM NaCl, 2.7 mM KCl, 4.3 mM Na2HPO4, 1.4 mM KH2PO4, pH = 7.4) in a ratio of 1:2, and incubated for 1 h in the dark at 37°C.…”

“…Fifty seminiferous tubule cross-sections per testis were randomly sampled and measured using a 920 objective lens. When sections were slightly oblique, only the minor axis was computed (Miraglia et al 1990;Stumpp et al 2004; Miranda-Spooner et al 2016).…”

“…The smears were stained according to Shorr/ haematoxylin methodology (Shorr 1941). Two hundred sperms were randomly counted and morphologically evaluated according to the descriptions established by Filler (1993) and adapted for the experimental model ( Miranda-Spooner et al 2016). The sperms were classified based on the criteria, which are as follows: shape of spermatozoa head; defects in the intermediate piece; defects in the tail; or with multiple abnormalities.…”

Resveratrol improves reproductive parameters of adult rats varicocelized in peripuberty

“…The morphological analysis of the sperms contained in these smears was processed under light microscope at 500× final magnification. Two-hundred sperms were randomly evaluated and the morphological abnormalities (head shape, isolated heads and tail defects) were performed according to the description of Filler et al (1993) and Miranda-Spooner et al (2016).…”

“…The sperm motility was evaluated using a computerized sperm analysis system (computer-assisted sperm analysis -CASA) and following the methodology described by Klinefelter et al (1991), with some modifications (Miranda-Spooner et al 2016). For this goal, after the dissection, the epididymal cauda was removed and subsequently transferred to 35 mm culture plates, containing Hank's balanced salt solution (HBSS -136,8 mM NaCl, 5,4 mM KCl, 0,3 mM Na2HPO4, 0,5 mM KH2PO4, 12 mM NaHCO3, pH 7,3), which was supplemented with 2 mg/mL BSA.…”