Ghrelin对大鼠胃黏膜上皮细胞胃酸分泌的调节作用

Relationship between ghrelin and abnormal gastric emptying in diabetes mellitus

In recent years, the morbidity of diabetes mellitus has increased rapidly in the world, and the harm of complications of diabetes mellitus has ranked third after cancer and cardiovascular and cerebrovascular diseases. Abnormal gastric emptying is one of the common complications of diabetic mellitus, which seriously influences the life quality of the patients. Therefore, it is important to investigate the pathogenesis of abnormal gastric emptying in diabetes mellitus. The role of ghrelin in the pathophysiology of abnormal gastric emptying in diabetes mellitus is a hot area of research now. In this paper, we review the relationship between ghrelin and abnormal gastric emptying in diabetes mellitus.

Role of ghrelin and NF-κB in the pathogenesis of acute necrotizing pancreatitis-associated liver injury

AIM: To investigate the expression of ghrelin in the liver of rats with acute necrotizing pancreatitis (ANP) with liver injury and to explore the role of ghrelin and NF-κB in the pathogenesis of ANP-associated liver injury and the mechanism underlying the therapeutic effects of melatonin against ANP.

METHODS: Seventy-two male Sprague-Dawley rats were randomly and equally divided into control group, ANP group, and melatonin intervention group. Rats of the ANP group and melatonin intervention group were injected with 6% L-Arg (1.5 g/kg) intraperitoneally three times to induce ANP. Rats of the control group were injected with same volume of normal saline. The melatonin intervention group was given 1% melatonin (50 μg/kg) intraperitoneally 0.5 h before the first injection of L-Arg. Rats were sacrificed at 6, 12, and 24 h after the injection of melatonin. Pathological changes in the pancreatic and hepatic tissue were observed and graded under a microscope. The expression of ghrelin and NF-κB mRNAs was evaluated by RT-PCR, while the protein expression of NF-κB was detected by Western blot.

RESULTS: Pancreatic and hepatic pathological scores, serum amylase, and expression of NF-κB mRNA (6 h: 0.74 ± 0.04 vs 0.40 ± 0.05; 12 h: 0.77 ± 0.03 vs 0.40 ± 0.02; 24 h: 0.82 ± 0.04 vs 0.40 ± 0.03, all P = 0.001) and protein in the liver at all time points were significantly higher (24 h: 0.48 ± 0.07 vs 0.6 ± 0.04, P < 0.05), and ghrelin mRNA expression was significantly lower in the ANP group than in the control group (6 h: 0.39 ± 0.04 vs 0.66 ± 0.03; 12 h: 0.14 ± 0.37 vs 0.30 ± 0.05; 24 h: 0.22 ± 0.02 vs 0.59 ± 0.05, all P < 0.05). Pancreatic pathological scores, hepatic pathological scores, serum amylase, and expression of NF-κB mRNA(6 h: 0.50 ± 0.05 vs 0.74 ± 0.04, 12 h: 0.54 ± 0.04 vs 0.77 ± 0.03, 24 h: 0.57 ± 0.03 vs 0.82 ± 0.04, all P < 0.05) and protein were decreased (24 h: 0.32 ± 0.04 vs 0.48 ± 0.07, P < 0.05), and ghrelin mRNA expression was elevated (6 h: 0.54 ± 0.03 vs 0.39 ± 0.04, 12 h: 0.40 ± 0.09 vs 0.30 ± 0.05, 24 h: 0.39 ± 0.04 vs 0.22 ± 0.02, all P < 0.05) in the melatonin intervention group compared with in the ANP group.

CONCLUSION: The expression of ghrelin may be related to the severity of ANP with liver injury. NF-κB may also be involved in the pathogenesis of ANP with liver injury. Exogenous melatonin can reduce ANP possibly by up-regulating ghrelin expression and down-regulating NF-κB expression.