Shenmai Injection Alleviates Acute Lung Injury in a Severe Acute Pancreatitis Rat Model via Heme Oxygenase-1 Upregulation.

Background: One of the serious complications of severe acute pancreatitis (SAP) is acute lung injury (ALI). Suppressing inflammation is a feasible treatment strategy for SAP-induced ALI. Shenmai injection (SMI), which is a Traditional Chinese Medicine (TCM treatment, can suppress inflammation. Therefore, this study used an established SAP rat model to determine the effect of SMI on ALI induced by SAP.
Methods: A total of 40 male Sprague-Dawley (SD) rats were assigned to one of four groups: the SAP group, the sham surgery (SS) group, the SAP + SMI group and the SAP + SMI + zinc protoporphyrin (ZnPP) group. Rats in the SAP group were intravenously injected with 1.6 ml/kg saline 30 minutes after induction of SAP models, rats in the SAP + SMI group were intravenously injected with 1.6 ml/kg SMI, while rats in the SAP + SMI + ZnPP group were intravenously injected with 1.6 ml/kg SMI and 30 mg/kg ZnPP via intraperitoneal injection. The rates were sacrificed 24 hours after SAP induction. Excised lung tissues were histologically examined, protein concentration in bronchoalveolar lavage fluid (BALF) was measured and lung wet-to-dry (W/D) weight ratio was calculated. The protein and mRNA levels of tumor necrosis factor (TNF)-α, heme oxygenase (HO)-1 and interleukin (IL)-10 in blood and tissue samples were measured.
Results: SMI treatment attenuated SAP-induced ALI as evidenced by lower lung damage scores compared with the untreated SAP group (P < .05). SMI also abolished the SAP-induced rise in BALF and W/D ratio protein concentrations (P < .05). Moreover, SMI treatment increased HO-1 and IL-10 levels but decreased TNF-α levels in serum and tissue samples (P < .05). However, inhibition of HO-1 expression by ZnPP led to significant inhibition of all the changes.
Conclusion: SMI can alleviate SAP-induced ALI through HO-1 upregulation.