Curcumin alone and in combination with augmentin protects against pulmonary inflammation and acute lung injury generated during Klebsiella pneumoniae B5055-induced lung infection in BALB/c mice

Acute lung injuries due to acute lung infections remain a major cause of mortality. Thus a combination of an antibiotic and a compound with immunomodulatory and anti-inflammatory activities can help to overcome acute lung infection-induced injuries. Curcumin derived from the rhizome of turmeric has been used for decades and it exhibits anti-inflammatory, anti-carcinogenic, immunomodulatory properties by downregulation of various inflammatory mediators. Keeping these properties in mind, we investigated the anti-inflammatory properties of curcumin in a mouse model of acute inflammation by introducing Klebsiella pneumoniae B5055 into BALB/c mice via the intranasal route. Intranasal instillation of bacteria in this mouse model of acute pneumonia-induced inflammation resulted in a significant increase in neutrophil infiltration in the lungs along with increased production of various inflammatory mediators [i.e. malondialdehyde (MDA), myeloperoxidase (MPO), nitric oxide (NO), tumour necrosis factor (INF)-alpha] in the lung tissue. The animals that received curcumin alone orally or in combination with augmentin, 15 days prior to bacterial instillation into the lungs via the intranasal route, showed a significant (P <0.05) decrease in neutrophil influx into the lungs and a significant (P <0.05) decrease in the production of MDA, NO, MPO activity and TNF-alpha levels. Augmentin treatment alone did not decrease the MDA, MPO, NO and TNF-alpha levels significantly (P>0.05) as compared to the control group. We therefore conclude that curcumin ameliorates lung inflammation induced by K pneumoniae B5055 without significantly (P <0.05) decreasing the bacterial load in the lung tissue whereas augmentin takes care of bacterial proliferation. Hence, curcumin can be used as an adjunct therapy along with antibiotics as an anti-inflammatory or an immunomodulatory agent in the case of acute lung infection.