Cell Membranes Become More Permeable From Use of DMSO and MSM
Source
| : Biofizika 2002 Sep-Oct;47(5):833-41 |
|
[Biophysical and medical and biological
aspects of use of polyene antibiotics in combination with dimethylsulfoxide]
[Article in Russian]
Ibragimova VKh, Aliev DI, Alieva IN.
Radiation Research Department, National Academy of Sciences of Azerbaidzhan,
Baku, Azerbaidzhan.
Modern conceptions of the physicochemical properties of dimethylsulfoxide and
polyene antibiotics are reviewed. The results of investigations of independent
and mutual effects of polyene antibiotics and dimethylsulfoxide on membrane
permeability were analysed. The own experimental data of radioprotective and
antitumour action of complex dimethylsulfoxide-polyene antibiotics are
presented, and the perspectives of their use in medicine are described.
Publication Types:
PMID: 12397953 [PubMed - indexed for MEDLINE]
Source
| J Neurocytol 2001 Sep-Oct;30(9-10):829-39 |
|
Dimethylsulfoxide enhances CNS neuronal plasma membrane
resealing after injury in low temperature or low calcium.
Shi R, Qiao X, Emerson N, Malcom A.
Department of Basic Medical Sciences, Institute for Applied Neurology, School of
Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA. riyi@vet.purdue.edu
The inability to repair the damaged membrane may be one of the key mechanisms
underlying the severe neuronal degeneration and overall functional loss seen in
in vivo spinal cord injury and traumatic axonal injury in blunt head trauma.
Promoting membrane resealing following damage may therefore constitute a
potential effective therapeutic intervention in treating head trauma and spinal
cord injuries. In our previous studies, we have shown that the axolemma failed
to reseal following transection in clinically related situations, such as low
extracellular calcium and low temperature. Our current studies indicate that
DMSO is capable of rendering significant improvement in guinea pig axonal
membrane resealing following transection in both 0.5 mM [Ca(2+)](0) and 25
degrees C situations. This was demonstrated physiologically by monitoring
membrane potential recovery and anatomically by conducting HRP-exclusion assays
60 minutes after injury. Further, we have shown that the addition of DMSO in
normal Krebs' solution (2 mM [Ca(2+)](0) and 37 degrees C) resulted in a
decrease in membrane repair following injury. This indicates that DMSO-mediated
membrane repair is sensitive to temperature and calcium. This study suggests the
role of DMSO in axonal membrane resealing in clinically relevant conditions and
raises the possibility of using DMSO in combination with other more established
therapies in spinal cord injury treatment.
PMID: 12165673 [PubMed - indexed for MEDLINE]
_____________________________
Abstract
The inability to repair the damaged membrane may be one of
the key mechanisms underlying the severe neuronal degeneration and overall
functional loss seen in in vivo spinal cord injury and traumatic axonal
injury in blunt head trauma.
Promoting membrane resealing following damage may therefore
constitute a potential effective therapeutic intervention in treating head
trauma and spinal cord injuries. In our previous studies, we have shown that the
axolemma failed to reseal following transection in clinically related
situations, such as low extracellular calcium and low temperature.
Our current studies indicate that DMSO is capable of
rendering significant improvement in guinea pig axonal membrane resealing
following transection in both 0.5 mM [Ca 2 ]0 and 25C situations.
This was demonstrated physiologically by monitoring
membrane potential recovery and anatomically by conducting HRP-exclusion assays
60 minutes after injury.
Further, we have shown that the addition of DMSO in normal
Krebs’ solution (2 mM [Ca 2 ]0 and 37C) resulted in a decrease in membrane
repair following injury. This indicates that DMSO-mediated membrane repair is
sensitive to temperature and calcium.
This study suggests the role of DMSO in axonal membrane
resealing in clinically relevant conditions and raises the possibility of using
DMSO in combination with other more established therapies in spinal cord injury
treatment.
Source
| Hum Reprod 2002 Jul;17(7):1875-84 |
|
Permeability characteristics and osmotic sensitivity of
rhesus monkey (Macaca mulatta) oocytes.
Songsasen N, Ratterree MS, VandeVoort CA, Pegg DE, Leibo SP.
Department of Biological Sciences, University of New Orleans and Audubon Center
for Research of Endangered Species, New Orleans, LA 70131, USA.
BACKGROUND: Permeability characteristics and sensitivity to osmotic shock are
principal parameters that are important to derive procedures for the successful
cryopreservation of mammalian oocytes. METHODS AND RESULTS: The osmotically
inactive volume of rhesus monkey oocytes was determined by measuring their
volumes in the presence of hypertonic solutions of sucrose from 0.2 to 1.5
mol/l, compared with their volume in isotonic TALP-HEPES solution. Boyle-van't
Hoff plots at infinite osmolality indicated that the non-osmotic volumes of
immature and mature oocytes were 20 and 17% respectively. Osmotic responses of
oocytes exposed to 1.0 mol/l solutions of glycerol, dimethylsulphoxide (DMSO)
and ethylene glycol (EG) were determined. Rhesus monkey oocytes appeared to be
less permeable to glycerol than to DMSO or to EG. Sensitivity of oocytes to
osmotic shock was determined by exposing them to various solutions of EG (0.1 to
5.0 mol/l) and then abruptly diluting them into isotonic medium. Morphological
survival, as measured by membrane integrity, of oocytes diluted out of EG
depended significantly on the concentration of EG (P < 0.01). CONCLUSION:
Determination of permeability characteristics and sensitivity to osmotic shock
of rhesus oocytes will aid in the derivation of procedures for their
cryopreservation.
PMID: 12093854 [PubMed - indexed for MEDLINE]
Source
| Cell Calcium 2002 Apr;31(4):183-8 |
|
Biochemical, biophysical and haemorheological effects of
dimethylsulphoxide on human erythrocyte calcium loading.
Santos NC, Figueira-Coelho J, Saldanha C, Martins-Silva J.
Instituto de Bioquimica/Instituto de Medicina Molecular, Faculdade de Medicina
de Lisboa, Portugal. nsantos@fm.ul.pt
The studies using dimethylsulphoxide (DMSO) and/or the 4-bromo-calcium ionophore
A23187 (Br-A23187) often neglect the precise knowledge of some of their
biochemical, biophysical and haemorheological effects. The aim of the present
study was to evaluate these effects on erythrocytes after whole blood
incubations with DMSO or Br-A23187 dissolved in DMSO. There were no significant
differences between the different aliquots in the values of P(50), pH,
erythrocyte deformability, erythrocyte membrane fluidity, haemoglobin and
intracellular Ca(2+) concentrations ([Ca(2+)](i)). Aliquots with DMSO
(independently of the presence of Br-A23187 or added Ca(2+)) had lower
erythrocyte aggregation indexes and higher plasma concentrations of K(+)],
Na(+)] and Ca(2+) than the aliquots without DMSO (independently of the presence
of added Ca(2+)). Aliquots with added calcium (without the presence of Br-A23187
in DMSO) had a significantly higher erythrocyte acetylcholinesterase activity.
Our data shows that calcium loading, the usual objective of Br-A23187
incubations, cannot be fulfilled with the studied experimental conditions. The
coherence between our results and those obtained by other authors with different
biological systems and different modulators of the rise on [Ca(2+)](i) suggests
a non-specific effect of DMSO, disabling the action of the modulator. It can be
reasoned that the decreased erythrocyte aggregation (without significant changes
on the deformability or membrane fluidity) can result either from the decrease
of the hydrogen bonding contribution to erythrocyte aggregation or the increased
ionic strength influence on the erythrocyte membrane surface. Copyright 2002,
Published by Elsevier Science Ltd.
PMID: 12027383 [PubMed - indexed for MEDLINE]
Source
| Eur J Pharm Sci 2002 May;15(4):331-40 |
|
Optimized conditions for MDCK permeability and turbidimetric
solubility studies using compounds representative of BCS classes I-IV.
Taub ME, Kristensen L, Frokjaer S.
Novo Nordisk A/S, Department of Drug Metabolism, Novo Nordisk Park, DK-2760
Maaloev, Denmark. mtaub@rdg.boehringer-ingelheim.com
The solubility enhancing effects of various excipients, including their
compatibility with in vitro permeability (P(app)) systems, was investigated
using drugs representative of Biopharmaceutics Classification System (BCS)
classes I-IV. Turbidimetric solubility determination using nephelometry and
transport experiments using MDCK Strain I cell monolayers were employed. The
highest usable concentration of each excipient [dimethyl sulfoxide (DMSO),
ethanol, hydroxypropyl-beta-cyclodextrin (HPCD), and sodium taurocholate] was
determined by monitoring apical (AP) to basolateral (BL) [14C]mannitol apparent
permeability (P(app)) and the transepithelial electrical resistance (TEER) in
transport experiments done at pH 6.0 and 7.4. The excipients were used in
conjunction with compounds demonstrating relatively low aqueous solubility (amphotericin
B, danazol, mefenamic acid, and phenytoin) in order to obtain a drug
concentration >50 microM in the donor compartment. The addition of at least one
of the selected excipients enhanced the solubility of the inherently poorly
soluble compounds to >50 microM as determined via turbidimetric evaluation at pH
6.0 and 7.4. Ethanol and DMSO were found to be generally disruptive to the MDCK
monolayer and were not nearly as useful as HPCD and sodium taurocholate. Sodium
taurocholate (5 mM) was compatible with MDCK monolayers under all conditions
investigated. Additionally, a novel in vitro system aimed at more accurately
simulating in vivo conditions, i.e., a pH gradient (6.0 AP/7.4 BL), sodium
taurocholate (5 mM, AP), and bovine serum albumin (0.25%, BL), was shown to
generate more reliable P(app) values for compounds that are poorly soluble
and/or highly protein bound.
PMID: 11988394 [PubMed - indexed for MEDLINE]
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