X-Message-Number: 30824
Date: Wed, 18 Jun 2008 22:14:06 -0700 (PDT)
From: 
Subject: taxol reduces vitrification damage

Mol Reprod Dev. 2008 Aug;75(8):1318-26.
Ultrastructure of bovine oocytes exposed to Taxol prior to OPS
vitrification.
    Morat  R, Mogas T, Maddox-Hyttel P. Departament de Medicina i Cirurgia
Animals. Facultat de Veterin ria. Universitat Aut noma de Barcelona,
Bellaterra, Spain.
    Our objective was to document potential subcellular consequences of
treatment with the microtubule stabilizer Taxol with or without subsequent
vitrification of cow and calf oocytes by the open pulled straw (OPS) method.
Oocytes were divided into four experimental groups for cows and four groups
for calves: (1) a control group fixed immediately after maturation; (2) an
OPS group cryopreserved by conventional OPS; (3) a Taxol/CPA group exposed
to 1 microM Taxol and cryoprotective agents (CPAs); and (4) a Taxol/OPS
group vitrified by OPS including 1 microM Taxol to the vitrification
solution. All oocytes were processed for light and transmission electron
microscopy. The main injuries were observed on the metaphase plate and the
spindle. In control oocytes, the metaphase appeared as condensed chromosomes
arranged in a well-organized metaphase plate and the spindle showed well
organized microtubules in both cow and calf oocytes. However, in cow OPS
oocytes, the metaphase plate was disorganized into scattered chromosomes or
the chromosomes were condensed into a single block of chromatin. In
addition, microtubules were not organized as typical spindles. In contrast,
cow Taxol/OPS oocytes as well as both cow and calf Taxol/CPAs oocytes showed
well-organized metaphase plates and normal spindle morphology. All calf OPS
and calf Taxol/OPS oocytes displayed a single block of chromatin and no
microtubules could be observed around the chromosomes. In conclusion,
treatment with 1 microM Taxol before and during vitrification did not induce
adverse changes in the oocyte cytoplasm or metaphase spindles in adult
bovine oocytes, but stabilized the metaphase and spindle morphology.
PMID: 18247367

Anim Reprod Sci. 2008 Jan 5. [Epub ahead of print]
Improved development of ovine matured oocyte following solid surface
vitrification (SSV): Effect of cumulus cells and cytoskeleton stabilizer.
    Zhang J, Nedambale TL, Yang M, Li J. Key Lab of Animal Genetics,
Breeding and Reproduction, College of Animal Science and Medicine, Inner
Mongolia Agriculture University, Huhhot, Inner Mongolia 010018, PR China.
    The objective of the present study was to examine the effects of cumulus
cells, cytochalasin B (CB), and taxol on the development of ovine matured
oocyte following solid surface vitrification (SSV). In experiment 1, effects
of cumulus cells during the vitrification were examined. Survival rates
after warming were not different between ovine mature oocytes with cumulus
cells and without cumulus cells. After in vitro fertilization, rates of
embryonic cleavage and development to blastocyst were not different between
these two groups. In experiment 2, the effects of cytochalasin B (CB) on
vitrification of ovine matured oocytes were examined. The rates of survived
ovine matured oocytes were not significantly different among the treatment
with 0, 2.5, 5.0, 7.5 and 10.0mug/mL CB. After in vitro fertilization, the
rate of cleavage was not different between the five treatment groups.
However, vitrified oocytes treated with 7.5 or 10.0mug/mL CB resulted in a
higher (8.1+/-4.6% and 7.8+/-2.4% respectively, P<0.05) blastocyst
development rate than those of oocytes treated with lower CB concentrations.
In Experiment 3, the effects of taxol on vitrification of ovine matured
oocytes were examined. The rate of survived oocytes was not significantly
different among the taxol treatment group with 0, 0.5, 1.0, and 5.0muM
taxol. After in vitro fertilization, the rates of embryos that reached
cleavage were not different between the four treatment groups. However,
vitrified oocytes treated with 0.5muM taxol resulted in a higher blastocyst
(10.1%+/-6.3, P<0.05) development rate compared to other treatment groups.
In conclusion, no effect of cumulus cells on vitrification of ovine matured
oocytes was detected in this study. Pretreatment of ovine matured oocytes
with cytoskeletal inhibitor cytochalasin B or taxol have a positive effect
and helps to reduce the damage induced by vitrification and is a potential
way to improve the development of vitrified/warmed ovine matured oocytes.
PMID: 18242892

Mol Reprod Dev. 2008 Jan;75(1):191-201.
Effects of pre-treating in vitro-matured bovine oocytes with the
cytoskeleton stabilizing agent taxol prior to vitrification.
    Morat  R, Izquierdo D, Albarrac n JL, Anguita B, Palomo MJ,
Jim nez-Macedo AR, Paramio MT, Mogas T. Departament de Medicina i Cirurgia
Animals, Facultat de Veterin ria, Universitat Aut noma de Barcelona, 08193
Bellaterra, Spain.
    The purpose of this study was to determine the efficacy of pre-treating
mature bovine oocytes with Taxol before vitrification by the open pulled
Straw method (OPS). We evaluated the effects of pre-treating the oocytes
with 1 microM Taxol on chromosome organization, spindle morphology, cortical
granule distribution and the ability of fertilized oocytes to develop to the
blastocyst stage. After calf or cow oocyte vitrification without Taxol,
significantly higher proportions of spindle abnormalities in the form of
abnormal spindle structures or dispersed or decondensed chromosomes were
observed compared to fresh control oocytes. In contrast, when we compared
calf oocytes pre-treated with Taxol before vitrification with control calf
oocytes, similar percentages of oocytes showing a normal spindle morphology
were observed. The percentages of oocytes with a peripheral cortical granule
(CG) distribution increased when the oocytes were pretreated with Taxol and
vitrified, while oocytes vitrified without Taxol pre-treatment gave rise to
higher cortical distribution percentages. Cleavage and blastocyst rates were
significantly lower for vitrified versus untreated oocytes, both in cow and
calf oocytes. Significantly higher cleavage rates were obtained when calf
and cow oocytes were vitrified with Taxol. Pre-treatment with Taxol before
cow oocyte vitrification yielded significantly higher blastocyst rates. Calf
oocytes, however, were unable to develop to the blastocyst stage,
irrespective of previous Taxol treatment. These results indicate that the
pre-treatment of oocytes with Taxol before vitrification helps to reduce the
damage induced by the cryopreservation process, and potentially improves the
subsequent development of vitrified bovine oocytes. Summary sentence:
Pre-treatment of oocytes with Taxol before vitrification helps to reduce the
damage induced by vitrification and potentially improves the development of
vitrified bovine oocytes. (c) 2007 Wiley-Liss, Inc.
PMID: 17474095

Reproduction. 2006 Apr;131(4):795-804.
Improved development by Taxol pretreatment after vitrification of in vitro
matured porcine oocytes.
    Shi WQ, Zhu SE, Zhang D, Wang WH, Tang GL, Hou YP, Tian SJ. Laboratory
of Animal Embryonic Biotechnology, College of Animal Science, China
Agricultural University; No. 2 Yuanmingyuan West Road, Haidian District,
Beijing 100094, PR China.
    This study was designed to examine the effect of Taxol pretreatment on
vitrification of porcine oocytes matured in vitro by an open pulled straw
(OPS) method. In the first experiment, the effect of Taxol pretreatment and
fluorescein diacetate (FDA) staining on parthenogenetic development of
oocytes was evaluated. In the second experiment, viability, microtubule
organization and embryo development of oocytes were assessed after oocytes
were exposed to vitrification/warming solutions or after vitrification with
or without Taxol pretreatment. The results showed that Taxol pretreatment
and/or FDA staining did not negatively influence the oocyte's developmental
competence after parthenogenetic activation. After being exposed to
vitrification/warming solutions, the survival rate (83.3%) of the oocytes
was significantly (P < 0.05) reduced as compared with that in the control
(100%). Vitrification/warming procedures further reduced the survival rates
of oocytes regardless of oocytes being treated with (62.1%) or without
(53.8%) Taxol. The proportions of oocytes with normal spindle configuration
were significantly reduced after the oocytes were exposed to
vitrification/warming solutions (38.5%) or after vitrification with (10.3%)
or without (4.1%) Taxol pretreatment as compared with that in control
(76.8%). The rates of two-cell-stage (5.6-53.2%) embryos at 48 h and
blastocysts (0-3.8%) at 144 h after activation were significantly reduced
after exposure to vitrification/warming solutions or after vitrification as
compared with control (90.9% and 26.6% respectively). However, the
proportion of vitrified oocytes developed to two-cell stage was
significantly higher when oocytes were pretreated with (24.3%) than without
(5.6%) Taxol. These results indicate that pretreatment of oocytes with Taxol
before vitrification helps to reduce the damage induced by vitrification and
is a potential way to improve the development of vitrified porcine oocytes.
PMID: 16595730

Cryobiology. 2005 Dec;51(3):339-43. Epub 2005 Sep 23.
Relationship between equilibration times and the presence of cumulus cells,
and effect of taxol treatment for vitrification of in vitro matured porcine
oocytes.
    Fujihira T, Nagai H, Fukui Y. Laboratory of Animal Reproduction, Obihiro
University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan.
    The effects of the presence or absence of cumulus cells and
equilibration times (1 and 4 min) with cryoprotectant, and Taxol treatment
before vitrification (0.5-5.0 microM) on development of in vitro matured
porcine oocytes after vitrification were examined. Ethylene glycol (30%) and
sucrose (0.5M) was used as a vitrification solution (39 degrees C), and
cryotop was used for cryo-container. There was a significant relationship (F
value: 6.077, P<0.05) in the rate of morphologically normal oocytes after
vitrification between the equilibration times and the presence or absence of
cumulus cells. The blastocyst rates were not significantly different between
Taxol (1.4-5.5%) and non-treated control (8.8%). The results show that the
optimal exposure time to achieve survival after vitrification depends on the
presence or absence of cumulus cells, and that Taxol has no positive effect
on the developmental capacity of vitrified, in vitro matured porcine
oocytes.
PMID: 16183050

J Assist Reprod Genet. 2004 Aug;21(8):307-9.
Freezing of human immature oocytes using cryoloops with Taxol in the
vitrification solution.
    Fuchinoue K, Fukunaga N, Chiba S, Nakajo Y, Yagi A, Kyono K. Department
of Gynecology and Urology, Ladies Clinic Kyono, Japan.
    PURPOSE: In human frozen immature oocytes, there has been little
successful delivery. We examined the feasibility of vitrification solution
including Taxol, cytoskeltal stabilizer. METHODS: We set four experimental
groups that immature oocytes has cumulus cells or not, or including Taxol or
not in the vitrification solution. Frozen-thawed oocytes have been performed
IVM, ICSI, and IVC. RESULTS: There were no significant differences in
survival, maturation, and fertilization rate, respectively. However, in the
group enveloped by cumulus cells and including Taxol in the vitrification
solution, one embryo was developed to blastocyst. CONCLUSIONS: Our results
showed that using vitrification solution with Taxol proved so effective.
PMID: 15568332

Fertil Steril. 2001 Jun;75(6):1177-84.
Cryopreservation of ICR mouse oocytes: improved post-thawed preimplantation
development after vitrification using Taxol, a cytoskeleton stabilizer.
    Park SE, Chung HM, Cha KY, Hwang WS, Lee ES, Lim JM. Infertility Medical
Center of CHA General Hospital, College of Medicine, Pochon CHA University,
Seoul, South Korea.
    OBJECTIVE: To establish an effective cryopreservation method. DESIGN: In
vitro model study. SETTING: Infertility Medical Center, Pochon CHA
University. ANIMAL(S): Four-week-old ICR mice superovulated with pregnant
mare serum gonadotropin (PMSG) and human chorionic gonadotropin.
INTERVENTION(S): Vitrified-thawed oocytes were fertilized and subsequently
cultured in vitro. MAIN OUTCOME MEASURE(S): Post-thawed development,
chromosome/spindle normalities, and blastocyst quality. RESULT(S): More
cumulus-enclosed oocytes were fertilized and developed to the 8-cell stage
after vitrification and thawing than denuded oocytes. However, cryopreserved
oocytes of both types had lower spindle and chromosome normalities than
fresh oocytes, which resulted in reduced developmental competence after
thawing. The addition of 1 microM of Taxol, a cytoskeleton stabilizer, to
vitrification solution greatly promoted the blastocyst formation of
vitrified-thawed oocytes, compared with no addition (24.0% vs. 58.6%). No
difference in blastocyst quality, which was evaluated by blastomere and
inner cell mass cell numbers and inner cell mass cell per trophoblast ratio,
was found between fresh oocytes and oocytes vitrified with Taxol.
CONCLUSION(S): A vitrification solution consisting of 5.5 M ethylene glycol,
1.0 M sucrose, 10% fetal bovine serum, and 1 microM Taxol greatly improved
post-thawed development of vitrified oocytes.
PMID: 11384646

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