Long-term high-fat diet induces pancreatic injuries via pancreatic microcirculatory disturbances and oxidative stress in rats with hyperlipidemia.
Relations between hyperlipidemia and chronic pancreatitis remain unclear. Microcirculatory disturbances and oxidative stress are involved in pathogeneses of a high numbers of diseases. The objective of this study was to induce hyperlipidemia in rats by long-term high-fat diet intake, then investigate the biochemical, microcirculatory, and histological alterations in blood and pancreatic tissues of these animals, and discuss their potential significances. Pancreatic blood flow was detected by intravital microscope; malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were measured in pancreatic tissues for assessment of oxidative stress and alpha-smooth muscle actin (alpha-SMA) expression was determined by immunohistochemical staining and RT-PCR. The results showed that the velocity of pancreatic microvascular blood flow of rats with hyperlipidemia decreased significantly as compared to control value (p = 0.008). Pancreatic MDA content increased whereas SOD activity decreased in these rats (p = 0.022; p = 0.039, respectively). Histologically, microvesicles in acinar and islet cells, dilated rough endoplasmic reticulum, swollen mitochondrion and modified vascular endothelial cells were observed under light microscope and transmission electron microscope. In addition, alpha-SMA expression was up-regulated significantly (p < 0.05). These results suggest that long-term high-fat diet can induce chronic pancreatic injuries which could be considered as "nonalcoholic fatty pancreatic disease", and pancreatic microcirculatory disturbances and oxidative stress may play an important part in the underlying pathogenesis.
Yan
Ming-Xian
MX
Department of Gastroenterology, Shandong University Qilu Hospital, Jinan, Shandong Province, China.
Li
Yan-Qing
YQ
Meng
Min
M
Ren
Hong-Bo
HB
Kou
Yi
Y
D000222:Adaptation, Physiological / Q000187:drug effects; D000818:Animals; D004041:Dietary Fats / Q000009:adverse effects*; D006949:Hyperlipidemias; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology*; D018384:Oxidative Stress / Q000187:drug effects; D010179:Pancreas / Q000098:blood supply / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D010182:Pancreatic Diseases / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013997:Time Factors
D004041:Dietary Fats; D017382:Reactive Oxygen Species