1. Antioxidative Effects on Male
Fertility: Roles of reactive oxygen
species (ROS) on D. melanogaster
fertility and sperm viability
Weily Lang, Preethi Radhakrishnan
CUNY LaGuardia Community College

2. HYPOTHESIS
• We hypothesized that when flies are fed
antioxidants, sperm viability and fertility will
increase because the antioxidants
accumulated within gametic tissue will help
rescue cells from prolonged paraquat-
induced ROS damage.

3. COLLECTED VIRGINS
STARVED MALES FOR 24 ISOLATED
HOURS FEMALES
FEED DIETS WITH
TREATMENTS:
MELATONIN LIPOIC ACID ETHANOL
(Antioxidant) (Antioxidant) (Control)
MATING
PARAQUAT ASSAULT & Copula
(induce ROS) Duration
SPERM FERTILITY
VIABILITY (Progeny Counts)

4. RESULTS

5. Results: Mating Probability
100
80
% Mated
60
40
20 M NM
0
ETHANOL MELATONIN LIPOIC ACID

6. Results: Copula Duration
30
Duration of mating (min)
25
20
15
10
5
0
ETHANOL MELATONIN LIPOIC ACID

7. Results: Sperm Viability
0.9
Proportion of Live Sperm
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
ETHANOL MELATONIN LIPOIC ACID

8. Results: Fertility
120
Total Number of Offspring
100
80
Produced
60 Male
Female
40
20
0
ETHANOL MELATONIN LIPOIC ACID

9. Conclusion
• Mating probability and Copula Duration:
− Antioxidant- fed treatments had no influence in male to female attraction or
mate guarding behavior.
− This indicates that feeding antioxidants does not significantly influence pre-
copulatory behaviors
• Sperm viability:
− Males fed Melatonin and Lipoic acid had a significantly higher proportion of
live sperm (74% and 56%) than the Ethanol treatment (32%).
− This indicated that both antioxidants Melatonin and Lipoic Acid, might protect
sperm from the lipid peroxidation activity of Paraquat
• Fertility:
− Males fed Melatonin and Lipoic acid sired significantly more offspring (mean = 187
and 148) the Ethanol treatment (mean = 82).
− This shows that antioxidant-fed males, passed more viable sperm to females than
the Ethanol treated flies, thereby siring more offspring.

10. References
1) Bonilla, E., et al., 2006. Paraquat –induced Oxidative stress in D. melanogaster: Effects
of Melatonin, Glutathione, Serotonin, Minocycline, Lipoic Acid and Ascorbic Acid.
Neurochem Res, 31:1425-1432
2) Bonilla, E, et al., 2002. Extension of life-span and stress resistance of D.melanogaster
by long-term supplementation with melatonin. Experimental Gerontology, 37:629-638.
3) Dowling, D, Simmons, L.W. 2009. Reactive oxygen species as universal constraints in
life-history evolution. Proc. R. Soc. B. 276: 1737-1745.
4) Aitken, J., Roman, D, S., Antioxidant Systems and Oxidative stress in the testes. 2008.
Molecular mechanisims in Spermatogenesis.
5) Radhakrishnan, P., Fedorka, K.MF. 2011. Influence of female age, sperm senescence
and multiple mating on sperm viability in female D. melanogaster. 57: 778-83
6) Radhakrishnan, P., Taylor, P.W. 2007. Seminal fluids mediate sexual inhibition and short
copula duration in mated female Quuensland fruit flies. 53: 741-745.

11. Acknowledgements
• Dr. Preethi Radhakrishnan
• NIH-Bridges R25 PAR-11-285
• Dr. Thomas Onorato
• Cheryl Pinzone, University of Georgia
• Judith O’Toole, CUNY LaGuardia Community
College

12. Questions
& Comments