The NJ4-pretreated mice with AP showed reduced acinar cell destruction and neutrophil infiltration (Figure (Figure33). The mortality rate in AP is approximately 20%-30%, and the major cause of AP-induced death is acute lung injury, referred to as acute respiratory distress syndrome. After Zotarolimus(ABT-578)? cytokines, or the digestive enzymes from the pancreas, attack the lung alveolar cells, inflammation and vascular injury occurs in the lung[8]. Cells that have infiltrated the pulmonary tissues cause breakdown of the pulmonary parenchyma[24]. This lung attack is particularly damaging in the elderly, and if they survive an attack, their quality of life is impaired[25-27]. Therefore, it is important to protect against lung injury caused by AP. In the present study, we showed that NJ4 treatment reduces lung injury and inflammation in AP (Figure (Figure44).

Experimental pancreatitis models and pancreatitis patients showed increased IL and TNF-�� levels[28-30]. IL-1��, IL-6, and TNF-�� play a pivotal role in AP, acting early in the disease course in addition to transitioning the acute inflammatory response to a chronic response[31,32]. We have previously reported that the total aqueous extract of NJ could inhibit cytokine production in mice with AP and LPS-induced cytokine production in macrophages[5,6]. Similar to the total aqueous extract of NJ, NJ4 inhibited serum and pancreatic cytokine production in mice with AP. HO-1 is a stress-inducible enzyme, whereas its isoform HO-2 is constitutively expressed[33]. HO-1 catabolizes heme into a free iron, carbon monoxide, and bilirubin/biliverdin[34].

Studies have shown that HO-1 has protective and anti-inflammatory effects on AP[35,36]. In the above experiment, the administration of HO-1 inducers resulted in significant induction of HO-1 in a specific target organ, the pancreas, and reduction in pro-inflammatory cytokines, a major factor in AP regulation. We have already reported that the protective mechanism of the total water extract of NJ on AP involves the inhibition of MAPKs. Similarly, NJ4 inhibited the activation of MAPKs, but the inhibition was not significant (data not shown). Therefore, we hypothesize that the main protective mechanism of NJ4 is via HO-1 upregulation. HO-1 was up-regulated 1 h after NJ4 injection, and the upregulation was dose-dependent. The HO-1 up-regulation by NJ4 was comparable with that observed with curcumin.

Furthermore, GSK-3 NJ4 induced expression of HO-1 in isolated pancreatic acinar cells at 3 h significantly; this finding is different from that of the in vivo experiment. In the in vivo experiment, NJ4 induced pancreatic HO-1 expression at 1 h significantly; however, in the in vitro experiment, NJ4 treatment led to the significant up-regulation of HO-1 at 3 h. We speculate that differences in metabolism between tissues and cells might be the reason for the difference in the expression time of HO-1 in the in vivo and in vitro experiments.