Post by John A. Casler on Jan 11, 2009 10:05:50 GMT -8
www.lef.org/news/LefDailyNews.htm?NewsID=7756&Section=Disease&source=DHB_090107&key=Body+Title
Research by K. Ganesan and colleagues in arthritis provides new insights
NewsRx.com
01-06-09
"Rheumatoid arthritis (RA) is a sexually dimorphic, autoimmune inflammatory disorder affecting the joints. Joint disability in RA results primarily from loss of matrix components (collagen and glycosoaminoglycan) in the cartilage and synovium," researchers in Chennai, India report (see also Arthritis).
"This study was carried out to understand the effect of physiological levels of testosterone, estrogen, and progesterone on oxidative stress-induced changes in matrix composition in rat synovium in arthritis. Arthritis induction in castrated and ovariectomized rats resulted in enhanced oxidative stress and this was assessed by lipid peroxidation levels and depletion of antioxidants. This, in turn, led to significantly (p < 0.01) increased levels of TNF-alpha and matrix metalloproteinase-2 (MMP-2), subsequently resulting in loss of collagen, elastin, and glycosoaminoglycan (GAG) and disorganization of reticulin as evidenced by biochemical quantitation and also by staining for collagen, reticulin, and elastin. Treatment with physiological doses of dihydrotestosterone (25 mg topically) and estrogen (5 mu g/0.1 ml subcutaneously) restored the antioxidant levels significantly (p < 0.05) and reduced the levels of TNF-alpha and MMP-2, with estrogen exhibiting a higher potency. This, in turn, attenuated the damage to reticulin organization as well as the loss of collagen and GAG in the articular tissues. However, elastin loss could not be attenuated by either treatment. Progesterone (2 mg/0.1 ml subcutaneously) was not shown to have any significance in disease modification, and on the contrary, it inhibited the protective effects of estrogen," wrote K. Ganesan and colleagues.
The researchers concluded: "However, progesterone contributed to increased collagen levels in the tissues."
Ganesan and colleagues published their study in Calcified Tissue International (Estrogen and Testosterone Attenuate Extracellular Matrix Loss in Collagen-Induced Arthritis in Rats. Calcified Tissue International, 2008;83(5):354-364).
For additional information, contact R. Puvanakrishnan, Cent. Leather Research Institute, Dept. of Biotechnology, Chennai 600020, Tamil Nadu, India.
Publisher contact information for the journal Calcified Tissue International is: Springer, 233 Spring St., New York, NY 10013, USA.
Keywords: India, Chennai, Arthritis, Autoimmune Disease, Autoimmune Disorder, Drugs, Enzyme Research, Immunology, Matrix Metalloproteinase, Metalloproteinases, Pharmaceuticals, Physiology, Progesterone, Proteins, Proteomics, Testosterone, Therapy, Treatment.
This article was prepared by Immunotherapy Weekly editors from staff and other reports. Copyright 2009, Immunotherapy Weekly via NewsRx.com.
Research by K. Ganesan and colleagues in arthritis provides new insights
NewsRx.com
01-06-09
"Rheumatoid arthritis (RA) is a sexually dimorphic, autoimmune inflammatory disorder affecting the joints. Joint disability in RA results primarily from loss of matrix components (collagen and glycosoaminoglycan) in the cartilage and synovium," researchers in Chennai, India report (see also Arthritis).
"This study was carried out to understand the effect of physiological levels of testosterone, estrogen, and progesterone on oxidative stress-induced changes in matrix composition in rat synovium in arthritis. Arthritis induction in castrated and ovariectomized rats resulted in enhanced oxidative stress and this was assessed by lipid peroxidation levels and depletion of antioxidants. This, in turn, led to significantly (p < 0.01) increased levels of TNF-alpha and matrix metalloproteinase-2 (MMP-2), subsequently resulting in loss of collagen, elastin, and glycosoaminoglycan (GAG) and disorganization of reticulin as evidenced by biochemical quantitation and also by staining for collagen, reticulin, and elastin. Treatment with physiological doses of dihydrotestosterone (25 mg topically) and estrogen (5 mu g/0.1 ml subcutaneously) restored the antioxidant levels significantly (p < 0.05) and reduced the levels of TNF-alpha and MMP-2, with estrogen exhibiting a higher potency. This, in turn, attenuated the damage to reticulin organization as well as the loss of collagen and GAG in the articular tissues. However, elastin loss could not be attenuated by either treatment. Progesterone (2 mg/0.1 ml subcutaneously) was not shown to have any significance in disease modification, and on the contrary, it inhibited the protective effects of estrogen," wrote K. Ganesan and colleagues.
The researchers concluded: "However, progesterone contributed to increased collagen levels in the tissues."
Ganesan and colleagues published their study in Calcified Tissue International (Estrogen and Testosterone Attenuate Extracellular Matrix Loss in Collagen-Induced Arthritis in Rats. Calcified Tissue International, 2008;83(5):354-364).
For additional information, contact R. Puvanakrishnan, Cent. Leather Research Institute, Dept. of Biotechnology, Chennai 600020, Tamil Nadu, India.
Publisher contact information for the journal Calcified Tissue International is: Springer, 233 Spring St., New York, NY 10013, USA.
Keywords: India, Chennai, Arthritis, Autoimmune Disease, Autoimmune Disorder, Drugs, Enzyme Research, Immunology, Matrix Metalloproteinase, Metalloproteinases, Pharmaceuticals, Physiology, Progesterone, Proteins, Proteomics, Testosterone, Therapy, Treatment.
This article was prepared by Immunotherapy Weekly editors from staff and other reports. Copyright 2009, Immunotherapy Weekly via NewsRx.com.
Research by K. Ganesan and colleagues in arthritis provides new insights
NewsRx.com
01-06-09
"Rheumatoid arthritis (RA) is a sexually dimorphic, autoimmune inflammatory disorder affecting the joints. Joint disability in RA results primarily from loss of matrix components (collagen and glycosoaminoglycan) in the cartilage and synovium," researchers in Chennai, India report (see also Arthritis).
"This study was carried out to understand the effect of physiological levels of testosterone, estrogen, and progesterone on oxidative stress-induced changes in matrix composition in rat synovium in arthritis. Arthritis induction in castrated and ovariectomized rats resulted in enhanced oxidative stress and this was assessed by lipid peroxidation levels and depletion of antioxidants. This, in turn, led to significantly (p < 0.01) increased levels of TNF-alpha and matrix metalloproteinase-2 (MMP-2), subsequently resulting in loss of collagen, elastin, and glycosoaminoglycan (GAG) and disorganization of reticulin as evidenced by biochemical quantitation and also by staining for collagen, reticulin, and elastin. Treatment with physiological doses of dihydrotestosterone (25 mg topically) and estrogen (5 mu g/0.1 ml subcutaneously) restored the antioxidant levels significantly (p < 0.05) and reduced the levels of TNF-alpha and MMP-2, with estrogen exhibiting a higher potency. This, in turn, attenuated the damage to reticulin organization as well as the loss of collagen and GAG in the articular tissues. However, elastin loss could not be attenuated by either treatment. Progesterone (2 mg/0.1 ml subcutaneously) was not shown to have any significance in disease modification, and on the contrary, it inhibited the protective effects of estrogen," wrote K. Ganesan and colleagues.
The researchers concluded: "However, progesterone contributed to increased collagen levels in the tissues."
Ganesan and colleagues published their study in Calcified Tissue International (Estrogen and Testosterone Attenuate Extracellular Matrix Loss in Collagen-Induced Arthritis in Rats. Calcified Tissue International, 2008;83(5):354-364).
For additional information, contact R. Puvanakrishnan, Cent. Leather Research Institute, Dept. of Biotechnology, Chennai 600020, Tamil Nadu, India.
Publisher contact information for the journal Calcified Tissue International is: Springer, 233 Spring St., New York, NY 10013, USA.
Keywords: India, Chennai, Arthritis, Autoimmune Disease, Autoimmune Disorder, Drugs, Enzyme Research, Immunology, Matrix Metalloproteinase, Metalloproteinases, Pharmaceuticals, Physiology, Progesterone, Proteins, Proteomics, Testosterone, Therapy, Treatment.
This article was prepared by Immunotherapy Weekly editors from staff and other reports. Copyright 2009, Immunotherapy Weekly via NewsRx.com.
Research by K. Ganesan and colleagues in arthritis provides new insights
NewsRx.com
01-06-09
"Rheumatoid arthritis (RA) is a sexually dimorphic, autoimmune inflammatory disorder affecting the joints. Joint disability in RA results primarily from loss of matrix components (collagen and glycosoaminoglycan) in the cartilage and synovium," researchers in Chennai, India report (see also Arthritis).
"This study was carried out to understand the effect of physiological levels of testosterone, estrogen, and progesterone on oxidative stress-induced changes in matrix composition in rat synovium in arthritis. Arthritis induction in castrated and ovariectomized rats resulted in enhanced oxidative stress and this was assessed by lipid peroxidation levels and depletion of antioxidants. This, in turn, led to significantly (p < 0.01) increased levels of TNF-alpha and matrix metalloproteinase-2 (MMP-2), subsequently resulting in loss of collagen, elastin, and glycosoaminoglycan (GAG) and disorganization of reticulin as evidenced by biochemical quantitation and also by staining for collagen, reticulin, and elastin. Treatment with physiological doses of dihydrotestosterone (25 mg topically) and estrogen (5 mu g/0.1 ml subcutaneously) restored the antioxidant levels significantly (p < 0.05) and reduced the levels of TNF-alpha and MMP-2, with estrogen exhibiting a higher potency. This, in turn, attenuated the damage to reticulin organization as well as the loss of collagen and GAG in the articular tissues. However, elastin loss could not be attenuated by either treatment. Progesterone (2 mg/0.1 ml subcutaneously) was not shown to have any significance in disease modification, and on the contrary, it inhibited the protective effects of estrogen," wrote K. Ganesan and colleagues.
The researchers concluded: "However, progesterone contributed to increased collagen levels in the tissues."
Ganesan and colleagues published their study in Calcified Tissue International (Estrogen and Testosterone Attenuate Extracellular Matrix Loss in Collagen-Induced Arthritis in Rats. Calcified Tissue International, 2008;83(5):354-364).
For additional information, contact R. Puvanakrishnan, Cent. Leather Research Institute, Dept. of Biotechnology, Chennai 600020, Tamil Nadu, India.
Publisher contact information for the journal Calcified Tissue International is: Springer, 233 Spring St., New York, NY 10013, USA.
Keywords: India, Chennai, Arthritis, Autoimmune Disease, Autoimmune Disorder, Drugs, Enzyme Research, Immunology, Matrix Metalloproteinase, Metalloproteinases, Pharmaceuticals, Physiology, Progesterone, Proteins, Proteomics, Testosterone, Therapy, Treatment.
This article was prepared by Immunotherapy Weekly editors from staff and other reports. Copyright 2009, Immunotherapy Weekly via NewsRx.com.