Chronic Maternal Tobacco Smoke Exposure and/or Alpha-Lipoic Acid Treatment Causes Long-Term Deterioration of Testis and Sexual Behavior in Adult Male Rats

BACKGROUND

Tobacco use during pregnancy is known to have several negative effects on the offspring's reproductive health in the long term. The use of alpha-lipoic acid (ALA) as a dietary supplement during pregnancy has increased greatly in recent years and has been known to have positive effects on various pregnancy outcomes including miscarriage, diabetic embryopathy, preterm delivery, and congenital malformations.

AIM

To evaluate the effects of tobacco smoke exposure (TSE) on sexual behavior, reproductive parameters, and testicles in adult male rats and to reveal the possible role of ALA administration on these parameters.

METHODS

Pregnant rats (n = 7 per group) were treated with tobacco smoke (TS), ALA (20 mg/kg), and TS + ALA for a total of 11 weeks. The following parameters were compared with 8 control rats: puberty parameters, sexual behavior; levels of serum gonadotropins and testosterone, total antioxidant status, and total oxidant status; the expression of the apoptotic protease-activating factor-1 and caspase 9 mRNA levels in the testis; and assessment of immunohistochemistry and terminal deoxynucleotidyl transferase dUTP nick end labeling assay of testis.

MAIN OUTCOME MEASURE

Sexual behavior, changes in puberty parameters, and hormonal and genetic alterations were the outcomes analyzed in this study.

RESULTS

Maternal TSE caused a significant decrease in the number of intromissions compared to the control group. Similarly, ALA decreased erectile function in sexual behavior by decreasing the number of intromissions and intromission ratio in the ALA group compared to the control group. In addition, TSE and ALA treatment caused an impairment of some consummatory sexual behaviors. Also, in parallel with this inhibitory effect, the age of pubertal onset was significantly delayed in the TS + ALA group compared to other groups. Also, histopathological changes in testicular tissue, oxidative stress markers, apoptotic index, and mRNA levels of apoptosis-related genes increased in all treatment groups.

CLINICAL IMPLICATIONS

The use of ALA and/or tobacco products during pregnancy may adversely affect the reproductive health of male newborns in the long term.

STRENGTHS & LIMITATIONS

To the best of our knowledge, this study is the first to show the effects of maternal ALA treatment and/or TSE on the sexual behavior and reproductive parameters in male rats; however, the study is based on an animal model, and the present findings partially reflect the characteristics of human sexual behavior.

CONCLUSION

Maternal TSE and/or ALA treatment may impair sexual behavior in adulthood in male rats because of testicular damage caused by oxidative stress during gonadal development. Yardimci A, Akkoc RF, Tektemur A, et al. Chronic Maternal Tobacco Smoke Exposure and/or Alpha-Lipoic Acid Treatment Causes Long-Term Deterioration of Testis and Sexual Behavior in Adult Male Rats. J Sex Med 2020;17:1835-1847.

Honey Extracted Polyphenolics Reduce Experimental Hypoxia in Human Keratinocytes Culture

Hypoxic assault affects fundamental cellular processes and generates oxidative stress on healthy cells/molecules. Honey extracted polyphenolics (HEP) as a natural antioxidant reduced hypoxic cytotoxicity in this study. Different honey samples were physicochemically characterized to identify preferred (jamun) honey [pH 3.55 ± 0.04, conductivity (μs/cm) = 6.66 ± 0.14, water content % (w/w) = 14.70 ± 0.35, total solid content % (w/w) = 85.30 ± 0.35, phenol content (mg GAE/100 g) = 403.55 ± 0.35, flavonoid content (mg QE/100 g) = 276.76 ± 4.10, radical scavenging activity (% 500 μL) = 147.75 ± 3.13, catalase activity (absorbance at 620 nm) = 0.226 ± 0.01]. HEP was tested in different doses on hypoxic and normoxic cells (HaCaT) using viability and antioxidant assays. Cardinal molecular expressions such as cadherin-catenin-cytoskeleton complex (namely, E-cadherin, β-catenin, and F-actin), hypoxia marker (Hif 1 α), proliferation marker (Ki67), and epithelial master regulator (p63) were studied by immuno-cytochemisty (ICC) and qRT-PCR. The 0.063 mg/mL HEP demonstrated better vitality and functionality of HaCaT cells as per viability assay (*, P < 0.01) even under hypoxia. ICC and qRT-PCR observations indicated restoration of cellular survival and homeostasis under 0.063 mg/mL HEP after hypoxic assault. Furthermore, major spectral changes for nucleic acid and membrane phospholipid reorganizations by Fourier transform infrared spectroscopy illustrated a positive impact of 0.063 mg/mL HEP on hypoxic cells considering proliferation and cellular integrity. It was concluded that a specific dose of jamun HEP reduces hypoxic cytotoxicity.

Dihydrolipoic but not alpha-lipoic acid affects susceptibility of eukaryotic cells to bacterial invasion

Sensitivity of eukaryotic cells to facultative pathogens can depend on physiological state of host cells. Previously we have shown that pretreatment of HeLa cells with N-acetylcysteine (NAC) makes the cells 2-3-fold more sensitive to invasion by the wild-type Serratia grimesii and recombinant Escherichia coli expressing gene of actin-specific metalloprotease grimelysin [1]. To evaluate the impact of chemically different antioxidants, in the present work we studied the effects of α-Lipoic acid (LA) and dihydrolipoic acid (DHLA) on efficiency of S. grimesii and recombinant E. coli expressing grimelysin gene to penetrate into HeLa and CaCo cells. Similarly to the effect of NAC, pretreatment of HeLa and CaCo cells with 0.6 or 1.25 mM DHLA increased the entry of grimelysin producing bacteria by a factor of 2.5 and 3 for the wild-type S. grimesii and recombinant E. coli, respectively. In contrast, pretreatment of the cells with 0.6 or 1.25 mM LA did not affect the bacteria uptake. The increased invasion of HeLa and CaCo cells correlated with the enhanced expression of E-cadherin and β-catenin genes, whereas expression of these genes in the LA-treated cells was not changed. Comparison of these results suggests that it is sulfhydryl group of DHLA that promotes efficient modification of cell properties assisting bacterial uptake. We assume that the NAC- and DHLA-induced stimulation of the E-cadherin-catenin pathway contributes to the increased internalization of the grimelysin producing bacteria within transformed cells.