Somatostatin analogue treatment attenuates histological findings of inflammation and increases mRNA expression of interleukin-1 beta in the articular tissues of rats with ongoing adjuvant-induced arthritis.
OBJECTIVE
Somatostatin is a neuropeptide with modulatory effects on the immune system and the function of synovial cells; it has antiangiogenic and antiproliferative properties. This study aimed to evaluate the clinical, histological, and articular tissue cytokine mRNA response to somostatin treatment in rat adjuvant-induced arthritis (AIA).


METHODS
Adjuvant-induced arthritis was induced in a total of 68 Lewis rats by immunization with complete Freund's adjuvant. Twenty-four rats were treated with a long-acting somostatin analogue 14 days after disease induction. Twenty-four untreated rats served as controls. The severity of arthritis was scored weekly for 42 days. In a second experiment, 20 rats (ten treated, ten controls) were killed 21 days after treatment for assessment of joint histopathology and articular tissue cytokine mRNA expression.


RESULTS
Somatostatin analogue treatment significantly reduced histological scores of early inflammatory changes and increased articular tissue mRNA expression of interleukin-1 beta (IL-1beta). A trend toward improvement in physical scores of joint inflammation was seen in the treated group. Late destructive changes were not significantly different.


CONCLUSIONS
Treatment with a somostatin analogue attenuated early inflammatory changes in AIA joints and increased mRNA expression of IL-1beta in the articular tissues of rats with ongoing arthritis. Improvement in the physical findings of joint inflammation was mild.
Paran
Daphna
D
Department of Rheumatology, Tel-Aviv Medical Center, Sackler School of Medicine, Tel-Aviv University, 6 Weizmann Street, Tel-Aviv 64239, Israel. Paran620@green.co.il
Kidron
Devora
D
Mayo
Ami
A
Ziv
Ofer
O
Chowers
Yehuda
Y
Caspi
Dan
D
Yaron
Michael
M
Paran
Haim
H
D000818:Animals; D001169:Arthritis, Experimental / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D007273:Injections, Intramuscular; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism*; D007596:Joints / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D015282:Octreotide / Q000627:therapeutic use*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011917:Rats, Inbred Lew; D016896:Treatment Outcome
D007375:Interleukin-1; D012333:RNA, Messenger; D015282:Octreotide