Siti Fatimah Ibrahim

A study of the antioxidant effect of alpha lipoic acids on sperm quality

OBJECTIVE Assisted reproductive techniques are useful in helping infertile couples achieve successful conception. Initial studies have shown that sperm cryopreservation, one step in assisted reproduction, causes a dramatic reduction in sperm quality. This has been attributed to, among other things, free radical activities. The aim of the present study was to minimize this oxidative attack by adding an antioxidant into the sperm microenvironment. Alpha lipoic acids were selected for this purpose for their efficient free radical scavenging properties and solubility in lipid and aqueous phases. METHODS For this investigation, semen from six Boer bucks was pooled. Seminal analysis of the baseline prior to incubation of samples with different concentrations of Alpha lipoic acids (0.00625, 0.0125, 0.025, 0.05, 0.1 mmol/ml) was performed, and post-seminal analysis was conducted after a one-hour incubation. The comet assay was used to observe the effect of Alpha lipoic acids on sperm DNA integrity. Statistical analysis using an unpaired t-test with a significance level of p<0.05 was then performed. RESULTS Our results indicate that the sperm motility rate was improved after incubation with Alpha lipoic acids at a concentration of 0.02 mmol/ml. This concentration was also capable of reducing DNA damage. CONCLUSION In conclusion, Alpha lipoic acids renders cryoprotection to sperm, thereby improving sperm quality.

Embryo apoptosis identification: Oocyte grade or cleavage stage?

Apoptosis is a programed cell death that is vital for tissue homeostasis. However, embryo apoptosis had been known to be related to embryo fragmentation which should be avoided in in vitro fertilization (IVF). The purpose of this study was to evaluate the relationship of embryo apoptosis with the grade of immature oocytes and cleavage stage of in vitro produced (IVP) cattle embryos. This study consisted of 345 oocytes collected through ovary slicing. Immature oocytes were graded as A, B and C. This grading was based on cumulus cell thickness and compactness. All oocytes then underwent an in vitro maturation (IVM) procedure. An IVF was done 24 h after IVM culture. Prior to staining, stage of cleaved embryos was determined and classified as either 2, 4, 8 or >8-cell embryo stage. Apoptosis status of cleaved IVP embryos was determined by using annexin V-FITC staining technique at 48 and 72 h post insemination (hpi). Apoptosis status for each embryo was classified as either early or late. The result showed that there was no significant difference (p > 0.05) of apoptosis status among grade A, B and C embryos. All grades of oocytes showed embryo apoptosis where 1.5% late apoptosis for grade A, 4.5% and 10.4% of early and late apoptosis for grade B and grade C. Early apoptosis was not seen in grade A embryo. We also noted no significant difference (p > 0.05) of apoptosis status between 2, 4, 8 and >8-cell embryo stage. Early apoptosis was also not seen in >8-cell stage. Even though there were no differences in apoptosis expression between the three classes, the cleavage rate of grade A oocytes was significantly higher (p < 0.01) than grade B and grade C. In conclusion, the apoptosis expression in the embryo can occur regardless of the oocyte quality and the cleavage stage of the embryo produced.

Melatonin ameliorates the adverse effects of leptin on sperm

This study examined the effects of melatonin on leptin-induced changes in sperm parameters in adult rats. Five groups of Sprague-Dawley rats were treated with either leptin or leptin and melatonin or melatonin for 6 weeks. Leptin was given daily via the intraperitoneal route (60 μg kg−1 body weight) and melatonin was given in drinking water (10 mg kg−1 or 20 mg kg−1 body weight per day). Upon completion, sperm count, sperm morphology, 8-hydroxy-2-deoxyguanosine, Comet assay, TUNEL assay, gene expression profiles of antioxidant enzymes, respiratory chain reaction enzymes, DNA damage, and apoptosis genes were estimated. Data were analyzed using ANOVA. Sperm count was significantly lower whereas the fraction of sperm with abnormal morphology, the level of 8-hydroxy-2-deoxyguanosine, and sperm DNA fragmentation were significantly higher in rats treated with leptin only. Microarray analysis revealed significant upregulation of apoptosis-inducing factor, histone acetyl transferase, respiratory chain reaction enzyme, cell necrosis and DNA repair genes, and downregulation of antioxidant enzyme genes in leptin-treated rats. Real-time polymerase chain reaction showed significant decreases in glutathione peroxidase 1 expression with increases in the expression of apoptosis-inducing factor and histone acetyl transferase in leptin-treated rats. There was no change in the gene expression of caspase-3 (CASP-3). In conclusion, the adverse effects of leptin on sperm can be prevented by concurrent melatonin administration.

Effect of Alcohol Consumption on the Sperm DNA Integrity: A Systematic Review

There is no solid conclusion on the conventional sperm parameters in association with alcohol consumption, evaluation of sperm DNA integrity thus become a more reliable parameter. Hereby, this literature search was performed to summarize alcohol consumption on the sperm DNA integrity. A computerized database search was done through MEDLINE via Ovid (since 1946 until August 2017) and Cochrane was used. The following set of keywords: ‘alcohol consumption OR alcohol intake OR alcohol diet OR drinking alcohol OR ethanol diet’ AND ‘sperm DNA OR sperm chromatin OR sperm genome OR sperm histone OR sperm protamine’ were utilised. 24 articles were retrieved where only five studies conform to the inclusion criteria All studies demonstrated a negative effect of alcohol consumption on sperm DNA integrity, regardless of various range of alcohol doses and duration of alcohol consumption. Out of five studies reviewed, four studies were using a different approach to measure the sperm DNA damage. Hereby, this review identified a need to use a single approach of DNA damage test by having various method of alcohol administration and/or vice versa so that the extension of sperm DNA damage to alcohol consumption will have a better conclusion. On the same note, a few studies have reported the reversibility on conventional semen parameters, none has been done on the sperm DNA damage upon alcohol withdrawal. Therefore, the role of alcohol withdrawal on the reversibility of sperm DNA damage needs to be as well investigated further.

Improvement of Post-Thaw Sperm Kinematics and DNA Integrity of Cross-Bred Bovine Sperm by Incorporating DGC as Selection Method Prior to Cryopreservation

The aim of this study was to assess post-thaw sperm quality following initial sperm selection using density gradient centrifugation (DGC) prior to cryopreservation. Ejaculates from four mature Charolais cross Kedah-Kelantan bulls were collected using artificial vagina at IBVK Pahang, Malaysia. The ejaculates were aliquoted into 3 groups: non-cryopreserved group (NC); control group of cryopreserved sperm without DGC (ND) and treatment group of sperm undergoing DGC sperm selection before cryopreservation (CDGC). Prior to analysis, samples from both cryopreserved groups were thawed at 37 °C for 30 sec. All samples were analysed for kinematics parameters, viability and compromise in DNA integrity (evaluated as DNA Fragmentation Index, DFI). All kinematics parameters were analysed using computer aided sperm analysis (CASA). Results indicated significant (p < 0.05) kinematics parameter changes for all parameters of velocity (VCL, VSL, VAP) and progression (WOB, LIN, ALH and BCF). Unfortunately, changes in spermatozoa straightness were insignificant (STR) F(2, 68) = 1.004, p = 0.371. Spermatozoa viability had increased by 26.2% (p < 0.01) following the treatment. DFI revealed the treatment group recorded a significant reduction in DFI value (0.17% fragmented DNA). In conclusion, DGC sperm selection prior to cryopreservation reduced the effects of cryodamage and showed an improvement in post-thaw sperm quality, thus reducing the occurrence of asthenozoospermia in populations of frozen-thawed cross-bred bovine spermatozoa.

Development of single tubing-type canister for cryo-storage of bull semen and their effect on sperm motility and viability

The objective of this study was to evaluate the potential of using single tubing-type canister on sperm quality. Semen was collected from the Bali cattle bull by electroejaculation technique and was cryopreserved in liquid nitrogen using slow freezing cryopreservation method. Two type of canister volume was used in this study; commercial canister (342.25π x 278 mm2) and single tubing-type canister (4π x 90 mm2). Makler counting chamber and computer assisted sperm analyzer (CASA) were used to evaluate the sperm motility and viability of post-thaw sperm. Results showed that the bull sperm motility and viability at the bottom of tubing-type canister was statistically higher and significant as compared to the commercial canister (p<0.05). Significant changes were found in sperm kinetics (VCL, VAP, VSL) of tubing-type canister compared to commercial canister. No significant changes in the motility and viability of the bull sperm at the top of tubing-type canister and commercial canister. There were no significant changes in sperm progression (LIN, WOB, PROG) in both the canisters. Developed tubing-type canister in this study showed potential as an alternative to be used in bull sperm cryo-storage.