Effect of the Total Extract of Averrhoacarambola (Oxalidaceae) Root on the Expression Levels of TLR4 and NF-κB in Streptozotocin-Induced Diabetic Mice.
BACKGROUND
Averrhoacarambola L., which is a folk medicine used in diabetes mellitus (DM) in ancient China, has been reported to have anti-diabetic efficacy.


OBJECTIVE
The aim of this study was to evaluate the hypoglycemic effect of the extract of Averrhoacarambola L. root (EACR) on the regulation of the Toll-like receptor 4 (TLR4)-Nuclear-factor kappa B (NF-κB) pathway in B) pathway in streptozotocin (STZ)-induced diabetic mice.


METHODS
the mice were injected with STZ (120 mg/kg body weight) via a tail vein. After 72 h, the mice with FBG ≥ 11.1 mmol/L were confirmed as having diabetes. Subsequently, the mice were treated intragastrically with EACR (300, 600, 1200 mg/kg body weight/d) and metformin (320 mg/kg body weight/d) for 14 days.


RESULTS
As a result the serum fasting blood glucose (FBG), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels were decreased following EACR administration. Immunohistochemical analysis revealed that the pancreatic tissue expression levels of TLR4 and NF-κB were downregulated after EACR administration. EACR suppressed pancreatic mRNA expression level of TLR4 and blocked the downstream NF-κB pathway in the pancreas. According to Western blot analysis EACR suppressed pancreatic TLR4 and NF-κB protein expression levels. Histopathological examination of the pancreas showed that STZ-induced pancreas lesions were alleviated by the EACR treatment.


CONCLUSIONS
These findings suggest that the modulation of the IL-6 and TNF-α inflammatory cytokines and the suppression of the TLR4-NF-κB pathway are most likely involved in the anti-hyperglycemic effect of EACR in STZ-induced diabetic mice.
Pharmaceutical College, Guangxi Medical University, Nanning, Guangxi, China.
Xiaohui
X
Xu
Tao
T
Liang
Xing
X
Lin
Qingwei
Q
Wen
Xingmei
X
Liang
Weisi
W
Li
Feizhang
F
Qin
Ni
N
Zheng
Jianjun
J
Ming
Renbin
R
Huang
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D015153:Blotting, Western; D001835:Body Weight / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D005215:Fasting / Q000097:blood; D007004:Hypoglycemic Agents / Q000494:pharmacology / Q000627:therapeutic use; D007328:Insulin / Q000378:metabolism; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D051379:Mice; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D065825:Oxalidaceae / Q000737:chemistry*; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D018517:Plant Roots / Q000737:chemistry*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013311:Streptozocin; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D015850:Interleukin-6; D016328:NF-kappa B; D010936:Plant Extracts; D012333:RNA, Messenger; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha; D013311:Streptozocin