Pre-inhalation of hydrogen-rich gases protect against caerulein-induced mouse acute pancreatitis while enhance the pancreatic Hsp60 protein expression

Background

Acute pancreatitis (AP) lacks targeted prevention and treatment measures. Some key points in the pathogenesis of AP remain unclear, such as early activation of pancreatic enzymes. Several recent reports have shown the protective effect of hydrogen on several AP animal models, and the mechanism is related to antioxidant activity. Heat shock protein 60 (Hsp60) is known to accompany pancreatic enzymes synthesis and secretion pathway of in pancreatic acinar cells, while role of hsp60 in AP remains a topic. Aim of this study was to investigate effect of hydrogen pretreatment on AP and the mechanisms, focusing on pancreatic oxidative stress and Hsp60 expression.

Methods

80 mice were randomly assigned into four groups: HAP group, AP group, HNS group, and NS group and each group were set 3 observation time point as 1 h, 3 h and 5 h (n = 6–8). Mouse AP model was induced by intraperitoneal injection of 50 μg/kg caerulein per hour for 6 injections both in AP and HAP groups, and mice in NS group and HNS group given normal saline (NS) injections at the same way as control respectively. Mice in HAP group and HNS group were treated with hydrogen-rich gases inhalation for 3 days before the first injection of caerulein or saline, while mice in AP group and NS group in normal air condition. Histopathology of pancreatic tissue, plasma amylase and lipase, plasma IL-1 and IL-6, pancreatic glutathione (GSH) and malondialdehyde (MDA), and Hsp60 mRNA and protein expression were investigated. Comparisons were made by one-way analysis of variance.

Results

The pancreatic pathological changes, plasma amylase and lipase activity, and the increase of plasma IL-1 and IL-6 levels in AP mice were significantly improved by the hydrogen-rich gases pretreatment, Meanwhile, the pancreatic GSH content increased and the pancreatic MDA content decreased. And, the hydrogen-rich gases pretreatment improved the Hsp60 protein expression in pancreatic tissues of AP mice at 1 h and 5 h.

Conclusions

Pre-inhalation of hydrogen-rich gases have a good protective effect on AP mice, and the possible mechanisms of reduced oxidative stress and the early increased pancreatic Hsp60 protein deserve attention.

Cinnamic acid nanoparticles modulate redox signal and inflammatory response in gamma irradiated rats suffering from acute pancreatitis

Acute Pancreatitis (AP) is a multifactorial disease. It was characterized by severe inflammation and acinar cell destruction. Thus, the present study was initiated to evaluate the role the of Cinnamic acid nanoparticles (CA-NPs) as a modulator for the redox signaling pathway involved in the development of pancreatitis. AP in rats was induced by L-arginine and exposure to gamma radiation. The pancreatic injury was evaluated using biochemical and histological parameters. Upon the oral administration of CA-NPs, both the severity of acute pancreatitis and the serum levels of amylase and lipase were decreased. Furthermore, the malondialdehyde (MDA) levels of the pancreatic tissue were significantly reduced and the depletion of glutathione was considerably restored. The injury and apoptosis of pancreatic tissues were markedly improved by the reduction of the caspase-3 levels. Additionally, the alleviation of pancreatic oxidative damage by CA-NPs was accompanied by a down-regulation of the NLRP3, NF-κB, and ASK1/MAPK signaling pathways. Collectively, the current findings showed that CA-NPs could protect the pancreatic acinar cell from injury not only by its antioxidant, anti-inflammatory effect but also by modulation of the redox-sensitive signal transduction pathways contributed to acute pancreatitis severity. Accordingly, cinnamic acid nanoparticles have therapeutic potential for the management of acute pancreatitis.

Possible mechanisms mediating the protective effect of cilostazol in L-arginine induced acute pancreatitis in rats: role of cGMP, cAMP, and HO-1

Acute pancreatitis (AP) is an inflammatory disorder with a high mortality rate. Cilostazol is a selective phosphodiesterase-3 inhibitor drug that is commonly used as an antiplatelet, antithrombotic, and vasodilator drug. It exhibits antioxidant, anti-inflammatory, and anti-apoptotic activities, but its effect on AP has not been fully elucidated yet. The present study aimed to investigate the effects of cilostazol on L-arginine-induced AP and the possible protective mechanisms. A rat model of AP was established by a single i.p. injection of 3-g/kg L-arginine on day 13 of the experiment. The treated groups received a single daily oral dose of either 100 or 300 mg/kg/day for 14 consecutive days. Rats with AP showed histopathological changes of pancreatic tissue injury together with increased serum amylase enzyme activity and decreased serum insulin, pancreatic adiponectin, and cGMP levels. Moreover, AP rats showed increased pancreatic inflammatory biomarker (TNF-α, VCAM-1, and MPO) levels with decreased anti-inflammatory IL-10 levels. In addition, oxidative stress biomarkers (MDA and NO) were increased in AP with decreased antioxidant SOD activity and GSH level. Moreover, HO-1 immunostaining was increased in the AP group. Cilostazol pretreatment reversed the histopathological change; decreased the amylase activity and the levels of TNF-α, VCAM-1, and MPO; and increased the levels of insulin, adiponectin, cGMP, cAMP, and IL-10. Moreover, cilostazol decreased MDA and NO but increased SOD and GSH. Lastly, cilostazol increased the HO-1 immunostaining more than in the AP group. These data suggest that cilostazol protects against L-arginine-induced AP, which may be related to an increase in cGMP, cAMP, and upregulation of HO-1 with subsequent anti-inflammatory and antioxidant properties.