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ironjustice@aol.com
Posted: Mon Nov 20, 2006 5:17 pm
Guest
Antioxidant effect of bisphosphonates and simvastatin on chondrocyte
lipid peroxidation.
Dombrecht EJ, De Tollenaere CB, Aerts K, Cos P, Schuerwegh AJ, Bridts
CH, Van Offel JF, Ebo DG, Stevens WJ, De Clerck LS
Biochem Biophys Res Commun. 2006 Sep 22; 348(2): 459-64

The objective of this study was to evaluate the effect of
bisphosphonates (BPs) and simvastatin on chondrocyte lipid
peroxidation. For this purpose, a flow cytometrical method using
C11-BODIPY(581/591) was developed to detect hydroperoxide-induced lipid
peroxidation in chondrocytes. Tertiary butylhydroperoxide (t-BHP)
induced a time and concentration dependent increase in chondrocyte
lipid peroxidation. Addition of a Fe2+/EDTA complex to t-BHP or
hydrogen peroxide (H2O2) clearly enhanced lipid peroxidation. The
lipophilic simvastatin demonstrated a small inhibition in the
chondrocyte lipid peroxidation. None of three tested BPs (clodronate,
pamidronate, and risedronate) had an effect on chondrocyte lipid
peroxidation induced by t-BHP. However, when Fe2+/EDTA complex was
added to t-BHP or H2O2, BPs inhibited the lipid peroxidation process
varying from 25% to 58%. This study demonstrates that BPs have
antioxidant properties as iron chelators, thereby inhibiting the
chondrocyte lipid peroxidation. These findings add evidence to the
therapeutic potential of bisphosphonates and statins in rheumatoid
arthritis.

-----------------------------------------------------------------

Bisphosphonates : CancerbackupInformation about bisphosphonates which
are used to help protect bones against some of the effects of cancer
particularly myeloma, breast cancer and ...
www.cancerbackup.org.uk/Treatments/Supportivetherapies/Bisphosphonates


BisphosphonatesBisphosphonates Bisphosphonates are a family of drugs
used to prevent and treat osteoporosis. There are three bisphosphonates
currently approved for use in ...
www.osteoporosis.ca/english/About%20Osteoporosis/Drug%20Treatments/Bisphosphonates/default.asp?s=1
- 28k -


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ironjustice@aol.com
Posted: Wed Nov 22, 2006 7:17 am
Guest
ironjustice@aol.com wrote:
Quote:
Antioxidant effect of bisphosphonates and simvastatin on chondrocyte
lipid peroxidation.
Dombrecht EJ, De Tollenaere CB, Aerts K, Cos P, Schuerwegh AJ, Bridts
CH, Van Offel JF, Ebo DG, Stevens WJ, De Clerck LS
Biochem Biophys Res Commun. 2006 Sep 22; 348(2): 459-64

The objective of this study was to evaluate the effect of
bisphosphonates (BPs) and simvastatin on chondrocyte lipid
peroxidation. For this purpose, a flow cytometrical method using
C11-BODIPY(581/591) was developed to detect hydroperoxide-induced lipid
peroxidation in chondrocytes. Tertiary butylhydroperoxide (t-BHP)
induced a time and concentration dependent increase in chondrocyte
lipid peroxidation. Addition of a Fe2+/EDTA complex to t-BHP or
hydrogen peroxide (H2O2) clearly enhanced lipid peroxidation. The
lipophilic simvastatin demonstrated a small inhibition in the
chondrocyte lipid peroxidation. None of three tested BPs (clodronate,
pamidronate, and risedronate) had an effect on chondrocyte lipid
peroxidation induced by t-BHP. However, when Fe2+/EDTA complex was
added to t-BHP or H2O2, BPs inhibited the lipid peroxidation process
varying from 25% to 58%. This study demonstrates that BPs have
antioxidant properties as iron chelators, thereby inhibiting the
chondrocyte lipid peroxidation. These findings add evidence to the
therapeutic potential of bisphosphonates and statins in rheumatoid
arthritis.

-----------------------------------------------------------------

Bisphosphonates : CancerbackupInformation about bisphosphonates which
are used to help protect bones against some of the effects of cancer
particularly myeloma, breast cancer and ...
www.cancerbackup.org.uk/Treatments/Supportivetherapies/Bisphosphonates


BisphosphonatesBisphosphonates Bisphosphonates are a family of drugs
used to prevent and treat osteoporosis. There are three bisphosphonates
currently approved for use in ...
www.osteoporosis.ca/english/About%20Osteoporosis/Drug%20Treatments/Bisphosphonates/default.asp?s=1
- 28k -


Who loves ya.
Tom


Jesus Was A Vegetarian!
http://jesuswasavegetarian.7h.com


Man Is A Herbivore!
http://tinyurl.com/a3cc3


DEAD PEOPLE WALKING
http://tinyurl.com/zk9fk

Risedronate is the latest of the bisphosphonates to be used for the
management of resorptive bone disease. Clinical improvements, assessed
by the incidence ...
www.medscape.com/viewarticle/414905

--------------------------------------------------------------------------------

Source: Johns Hopkins Medical Institutions Released: Tue
21-Nov-2006, 16:00 ET
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Millions with Arthritis May Benefit from Bone Loss Drug
Libraries
Medical News Keywords
ARTHRITIS BONE LOSS RHEUMATOLOGY OSTEOPOROSIS OSTEOARTHRITIS
Contact Information

Available for logged-in reporters only
Description

People taking a widely used medication to strengthen fragile, aging
bones may also be protecting their joints, according to a recent study
led by Johns Hopkins rheumatologist Clifton Bingham, M.D.


Newswise - People taking a widely used medication to strengthen
fragile, aging bones may also be protecting their joints, according to
a recent study led by Johns Hopkins rheumatologist Clifton Bingham,
M.D.

Researchers began to wonder if risedronate might be used to treat
osteoarthritis after noticing that the drug, and other compounds in the
same class of drugs, not only slowed joint damage in animals, but also
reduced cartilage-irritating bone lesions in humans.

For two years, an international team of investigators studied 2,483
arthritic men and women, from both the United States and Europe. All of
those enrolled in the study had a loss in the cartilage that cushions
the knee joint, a hallmark symptom of osteoarthritis.

Reporting in the most recent issue of the medical journal Arthritis &
Rheumatism, Bingham and his team said study participants were given
either a placebo or risedronate at a range of doses, including the
standard doses normally prescribed to treat bone loss. The amount of
cartilage detected in their knees was measured by X-ray analysis at the
one- and two-year marks. Blood tests were also used to check for a
marker of cartilage breakdown known as CTX-II.

CTX-II is released in the bloodstreams of people with osteoarthritis
when cartilage begins to fray. How fast and to what degree cartilage
breaks down can be approximated by levels of CTX-II.

"The blood tests revealed not only that risedronate stabilized bone
loss, but also that it was most likely slowing the breakdown of
cartilage, too" says Bingham.

Bingham emphasizes that X-rays failed to show any dramatic visible
changes in the structure of the joints with risedronate compared to a
placebo: however, the numbers of patients exhibiting significant
progression of the disease were few in all treatment groups. A great
challenge now is identifying the risk factors for joint deterioration
in osteoarthritis, adds Bingham.

The investigators also did not see a significant reduction in joint
pain with risedronate compared with the placebo.

In the United States, where an estimated 25 million people have
osteoarthritis and 44 million have osteoporosis, participants in the
study group taking risedronate experienced a noticeable drop in their
CTX-II levels: 17.9 percent. The Europeans fared even better, with a
19.6 percent decrease. Patients taking the drug at normal levels and at
higher than usual doses given for comparison experienced similar
slowdowns in cartilage decline, without significant adverse side
effects.

Those in the placebo group, however, experienced increases in CTX-II
levels (26.3 percent for the Americans and 10.1 percent for the
Europeans), suggesting that their cartilage was deteriorating faster
than that in those taking the drug.

"We are not recommending that everyone with arthritis run out and get
a prescription for these kinds of drugs, nor are we suggesting at this
time that doctors use risedronate as an arthritis treatment,"
cautions Bingham. "But what we can say now is that drugs affecting
bone turnover need to be further evaluated for their potential effects
as arthritis therapies."

The blood test changes seen in the study would suggest that people
already taking bone strengthening drugs may be simultaneously helping
their joints, concludes Bingham.

NOTE: Dr. Bingham has received consulting fees from Proctor & Gamble
Pharmaceuticals, the makers of Actonel, the brand name for risedronate.
Additionally, several other members of his research team have received
consulting fees from other pharmaceutical companies.



--------------------------------------------------------------------------------

© 2006 Newswise. All Rights Reserved.


Who loves ya.
Tom


Jesus Was A Vegetarian!
http://jesuswasavegetarian.7h.com


Man Is A Herbivore!
http://tinyurl.com/a3cc3


DEAD PEOPLE WALKING
http://tinyurl.com/zk9fk
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