Nelson Vergel
Founder, ExcelMale.com
Ultraviolet filters mimic progesterone, interfere with sperm function
BOSTON — Certain ultraviolet filters commonly found in sunscreens induce a calcium signal in human sperm, mimicking progesterone and affecting sperm function, according to study findings presented here.
“Progesterone-induced calcium signaling, and the sperm functions it triggers, is absolutely essential for the human sperm cell to normally fertilize the human egg,” Anders Rehfeld, MD, a PhD student in the department of cellular and molecular medicine at the University of Copenhagen, told Endocrine Today. “Our study shows that 13 out of 29 tested chemical UV filters can also induce calcium signals in human sperm cells, thereby mimicking the effect of progesterone and possibly interfering with the fertilizing ability of human sperm cells.”
Rehfeld and colleagues analyzed 29 of 31 UV filters approved for use in sunscreens in the United States or European Union. Researchers used calcium fluorimetry to determine the ability of the UV filters to induce a Ca2+ influx in human sperm, and whether the influx involved sperm cation channels (CatSper). Researchers tested the effect of the UV filters on sperm motility, penetration in viscous media, viability and acrosomal exocytosis.
Researchers found that 13 of the 29 UV filters (44%) induced mean Ca2+ signals in human sperm larger than the mean Ca2+ signal of negative controls. The most efficient UV filters, 4-MBC and 3-BC, induced mean Ca2+ influxes at 10 µM, reaching 97% and 92%, respectively, of the maximal Ca2+ influx induced by progesterone. Nine of the 13 UV filters directly activated the CatSper channel to induce a Ca2+ influx, mimicking the action of progesterone, according to researchers; three UV filters inhibited progesterone response.
In assessing dose response relations, all except one of the 13 UV filters produced saturating curves, with mean EC50 vales between 0,417 and 7,014 µM. The 13 UV filters acted additively in mixtures of 100 nM each (n = 3).
Researchers also found UV filters affected sperm motility, penetration in viscous media, viability and acrosomal exocytosis in vitro.
“We tested this in vitro on ejaculated sperm cells ... and our results are quite disturbing,” Rehfeld told Endocrine Today. “You get substantial effects with these UV filters at low concentrations. We don’t know if you would see the same effects in vivo, during the fertilization process, but if you do, it’s troubling. It could be a bad idea to use UV sunscreens, for example, if you’re trying to conceive.” – by Regina Schaffer
Reference :
Rehfeld A, et al. FRI-121. Presented at: The Endocrine Society Annual Meeting; April 1-4, 2016; Boston.
http://www.healio.com/endocrinology..._medium=email&utm_campaign=endocrinology news
BOSTON — Certain ultraviolet filters commonly found in sunscreens induce a calcium signal in human sperm, mimicking progesterone and affecting sperm function, according to study findings presented here.
“Progesterone-induced calcium signaling, and the sperm functions it triggers, is absolutely essential for the human sperm cell to normally fertilize the human egg,” Anders Rehfeld, MD, a PhD student in the department of cellular and molecular medicine at the University of Copenhagen, told Endocrine Today. “Our study shows that 13 out of 29 tested chemical UV filters can also induce calcium signals in human sperm cells, thereby mimicking the effect of progesterone and possibly interfering with the fertilizing ability of human sperm cells.”
Rehfeld and colleagues analyzed 29 of 31 UV filters approved for use in sunscreens in the United States or European Union. Researchers used calcium fluorimetry to determine the ability of the UV filters to induce a Ca2+ influx in human sperm, and whether the influx involved sperm cation channels (CatSper). Researchers tested the effect of the UV filters on sperm motility, penetration in viscous media, viability and acrosomal exocytosis.
Researchers found that 13 of the 29 UV filters (44%) induced mean Ca2+ signals in human sperm larger than the mean Ca2+ signal of negative controls. The most efficient UV filters, 4-MBC and 3-BC, induced mean Ca2+ influxes at 10 µM, reaching 97% and 92%, respectively, of the maximal Ca2+ influx induced by progesterone. Nine of the 13 UV filters directly activated the CatSper channel to induce a Ca2+ influx, mimicking the action of progesterone, according to researchers; three UV filters inhibited progesterone response.
In assessing dose response relations, all except one of the 13 UV filters produced saturating curves, with mean EC50 vales between 0,417 and 7,014 µM. The 13 UV filters acted additively in mixtures of 100 nM each (n = 3).
Researchers also found UV filters affected sperm motility, penetration in viscous media, viability and acrosomal exocytosis in vitro.
“We tested this in vitro on ejaculated sperm cells ... and our results are quite disturbing,” Rehfeld told Endocrine Today. “You get substantial effects with these UV filters at low concentrations. We don’t know if you would see the same effects in vivo, during the fertilization process, but if you do, it’s troubling. It could be a bad idea to use UV sunscreens, for example, if you’re trying to conceive.” – by Regina Schaffer
Reference :
Rehfeld A, et al. FRI-121. Presented at: The Endocrine Society Annual Meeting; April 1-4, 2016; Boston.
http://www.healio.com/endocrinology..._medium=email&utm_campaign=endocrinology news
