El Roundup i el seu component actiu glifosat, tòxic per cèl.lules testiculars de ratolí

Us traduïm l’abstract de dos articles molt recents (un d’ara, altre del 2010) sobre els efectes de disrupció endocrina en el nivell de testosterona de ratolins  per part del Roundup i del glifosat, a dosis molt diluïdes, i dels efectes letals sobre les cèl·lules testiculars  a concentracions més altes (però encara més baixes que les que es fan servir a l’agricultura). La investigació científica ha estudiat els efectes aguts, que es poden observar en 24-48 hores, i no els   problemes crònics, com podrien ser infertilitat o altres malalties que podria comportar la disrupció hormonal a llarg plaç.

Toxicology in Vitro
Volume 26, Issue 2, March 2012, Pages 269-279
ISSN: 08872333
CODEN: TIVIE
DOI: 10.1016/j.tiv.2011.12.009

A glyphosate-based herbicide induces necrosis and apoptosis in mature rat
testicular cells in vitro, and testosterone decrease at lower levels

Clair, É.a b , Mesnage, R.a b , Travert, C.a , Séralini, G.-É.a b

a  Université de Caen Basse-Normandie, EA2608, Institute of Biology,
Esplanade de la Paix, 14032 Caen Cedex, France
b  Université de Caen Basse-Normandie, Risk Pole MRSH-CNRS, CRIIGEN, 40
rue de Monceau, 75008 Paris, France

Abstract

The major herbicide used worldwide, Roundup, is a glyphosate-based
pesticide with adjuvants. Glyphosate, its active ingredient in plants
and its main metabolite (AMPA) are among the first contaminants of
surface waters. Roundup is being used increasingly in particular on
genetically modified plants grown for food and feed that contain its
residues. Here we tested glyphosate and its formulation on mature rat
fresh testicular cells from 1 to 10000. ppm, thus from the range in
some human urine and in environment to agricultural levels. We show
that from 1 to 48. h of Roundup exposure Leydig cells are damaged.
Within 24-48. h this formulation is also toxic on the other cells,
mainly by necrosis, by contrast to glyphosate alone which is
essentially toxic on Sertoli cells. Later, it also induces apoptosis
at higher doses in germ cells and in Sertoli/germ cells co-cultures.
At lower non toxic concentrations of Roundup and glyphosate (1. ppm),
the main endocrine disruption is a testosterone decrease by 35%. The
pesticide has thus an endocrine impact at very low environmental
doses, but only a high contamination appears to provoke an acute rat
testicular toxicity. This does not anticipate the chronic toxicity
which is insufficiently tested, and only with glyphosate in regulatory
tests.

Tambè he trobat un altre una mica més antic:

Archives of Toxicology
Volume 84, Issue 4, April 2010, Pages 309-317
ISSN: 03405761
CODEN: ARTOD
DOI: 10.1007/s00204-009-0494-z
PubMed ID: 20012598
Document Type: Article
Source Type: Journal

Prepubertal exposure to commercial formulation of the herbicide glyphosate
alters testosterone levels and testicular morphology

Romano, R.M.a d  , Romano, M.A.b , Bernardi, M.M.c , Furtado, P.V.a ,
Oliveira, C.A.a

a  Department of Animal Reproduction, Veterinary Medicine School,
University of Sao Paulo, Sao Paulo, Brazil
b  Department of Pharmacy, State University of Centro-Oeste, Parana, Brazil
c  Department of Pathology, Veterinary Medicine School, University of Sao
Paulo, Sao Paulo, Brazil
d  LDH/FMVZ/USP, Av Prof Dr Orlando Marques de Paiva, 87, Sao Paulo, SP
CEP 05508270, Brazil

Abstract

Glyphosate is a herbicide widely used to kill weeds both in
agricultural and non-agricultural landscapes. Its reproductive
toxicity is related to the inhibition of a StAR protein and an
aromatase enzyme, which causes an in vitro reduction in testosterone
and estradiol synthesis. Studies in vivo about this herbicide effects
in prepubertal Wistar rats reproductive development were not performed
at this moment. Evaluations included the progression of puberty, body
development, the hormonal production of testosterone, estradiol and
corticosterone, and the morphology of the testis. Results showed that
the herbicide (1) significantly changed the progression of puberty in
a dose-dependent manner; (2) reduced the testosterone production, in
semineferous tubules’ morphology, decreased significantly the
epithelium height (P < 0.001; control = 85.8 ± 2.8 μm; 5 mg/kg = 71.9
± 5.3 μm; 50 mg/kg = 69.1 ± 1.7 μm; 250 mg/kg = 65.2 ± 1.3 μm) and
increased the luminal diameter (P < 0.01; control = 94.0 ± 5.7 μm; 5
mg/kg = 116.6 ± 6.6 μm; 50 mg/kg = 114.3 ± 3.1 μm; 250 mg/kg = 130.3 ±
4.8 μm); (4) no difference in tubular diameter was observed; and (5)
relative to the controls, no differences in serum corticosterone or
estradiol levels were detected, but the concentrations of testosterone
serum were lower in all treated groups (P < 0.001; control = 154.5 ±
12.9 ng/dL; 5 mg/kg = 108.6 ± 19.6 ng/dL; 50 mg/dL = 84.5 ± 12.2
ng/dL; 250 mg/kg = 76.9 ± 14.2 ng/dL). These results suggest that
commercial formulation of glyphosate is a potent endocrine disruptor
in vivo, causing disturbances in the reproductive development of rats
when the exposure was performed during the puberty period. © 2009
Springer-Verlag