Nardostachys jatamansi extract protects against cytokine-induced beta-cell damage and streptozotocin-induced diabetes.
OBJECTIVE
To investigate the anti-diabetogenic mechanism of Nardostachys jatamansi extract (NJE).


METHODS
Mice were injected with streptozotocin via a tail vein to induce diabetes. Rat insulinoma RINm5F cells and isolated rat islets were treated with interleukin-1beta and interferon-gamma to induce cytotoxicity.


RESULTS
Treatment of mice with streptozotocin resulted in hyperglycemia and hypoinsulinemia, which was confirmed by immunohistochemical staining of the islets. The diabetogenic effects of streptozotocin were completely abolished when mice were pretreated with NJE. Inhibition of streptozotocin-induced hyperglycemia by NJE was mediated by suppression of nuclear factor (NF)-kappaB activation. In addition, NJE protected against cytokine-mediated cytotoxicity. Incubation of RINm5F cells and islets with NJE resulted in a significant reduction in cytokine-induced NF-kappaB activation and downstream events, inducible nitric oxide synthase expression and nitric oxide production. The protective effect of NJE was further demonstrated by the normal insulin secretion of cytokine-treated islets in response to glucose.


CONCLUSIONS
NJE provided resistance to pancreatic beta-cell damage from cytokine or streptozotocin treatment. The beta-cell protective effect of NJE is mediated by suppressing NF-kappaB activation.
Song
Mi-Young
MY
Department of Biochemistry, Medical School and Diabetes Research Center, Chonbuk National University, Jeonju, Jeonbuk 561-756, South Korea.
Bae
Ui-Jin
UJ
Lee
Bong-Hee
BH
Kwon
Kang-Beom
KB
Seo
Eun-A
EA
Park
Sung-Joo
SJ
Kim
Min-Sun
MS
Song
Ho-Joon
HJ
Kwon
Keun-Sang
KS
Park
Jin-Woo
JW
Ryu
Do-Gon
DG
Park
Byung-Hyun
BH
D000818:Animals; D001483:Base Sequence; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D016207:Cytokines / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D017931:DNA Primers / Q000235:genetics; D003921:Diabetes Mellitus, Experimental / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000473:pathology / Q000502:physiology; D007371:Interferon-gamma / Q000037:antagonists & inhibitors / Q000633:toxicity; D053583:Interleukin-1beta / Q000037:antagonists & inhibitors / Q000633:toxicity; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D016328:NF-kappa B / Q000378:metabolism; D032404:Nardostachys; D052247:Nitric Oxide Synthase Type II / Q000235:genetics; D010936:Plant Extracts / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects
D016207:Cytokines; D017931:DNA Primers; D007004:Hypoglycemic Agents; D007328:Insulin; D053583:Interleukin-1beta; D016328:NF-kappa B; D010936:Plant Extracts; D007371:Interferon-gamma; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat