Bacterial and viral pneumonia: New insights from the Drakenstein Child Health Study

Kurarinone Attenuates LPS-Induced Pneumonia by Inhibiting MAPK and NF-κB Signaling Pathways

Kurarinone is a prenylated flavanone isolated from Sophora flavescens Aiton. This investigation aimed to elucidate whether kurarinone could ameliorate lipopolysaccharide (LPS)-induced pneumonia and explore the underlying mechanism. C57BL/6 mice were treated with LPS (50 μg/20 μL) to establish pneumonia models. Kurarinone (100 mg/kg) or dexamethasone (DEX, 5 mg/kg) was administered for 7 days before LPS inhalation. BEAS-2B cells were incubated with kurarinone at 1, 2, and 5 μM for 2 h before LPS stimulation for 24 h. We found that kurarinone ameliorated lung injury and inflammatory cell infiltration in the mouse lung (p < 0.001). Kurarinone decreased MPO activity (47.6%, p < 0.001) and alleviated the inflammatory response by reducing the levels of IL-1β (34.9%, p < 0.001), TNF-α (55.1%, p < 0.001), and IL-6 (36.2%, p < 0.001) in the lung. Kurarinone reduced the levels of IL-1β, TNF-α, IL-6, iNOS, and COX2 in LPS-treated BEAS-2B cells in a concentration-dependent manner (p < 0.05). Mechanistically, kurarinone restrained LPS-induced activation of MAPK and NF-κB pathways in vivo and in vitro (p < 0.05). Overall, kurarinone alleviates LPS-induced pneumonia in mice by reducing inflammation via MAPK and NF-κB pathways, suggesting that kurarinone might be a potential therapeutic agent for pneumonia. This study provides new research ideas for the discovery of natural flavonoids that can treat pneumonia.

Serum Cytokines and FeNO in School-Aged Children with Mycoplasma pneumoniae Pneumonia

Background

Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) that is particularly prevalent in school-aged children. This study explored the potential involvement of cytokines in children with Mycoplasma pneumoniae pneumonia (MPP) infection.

Material/Methods

Children aged 3–7 years who were hospitalized due to CAP infection were enrolled and divided into 2 groups: an MPP group (n=33) and a NMPP group (n=38), along with 21 age-matched healthy controls. Clinical characteristics and laboratory data were recorded. Serum levels of IL-18, IL-33, IFN-γ, IL-5, IL-6, IL-8, and IL-13 were assessed using Luminex xMAP technology. Correlation analysis and ROC curves analysis were also performed to further explore the role of these detected cytokines in CAP.

Results

Compared with the healthy controls, the serum expression of IL-18, IL-33, IFN-γ, IL-5, IL-6, IL-8, and IL-13 were significantly higher in the MPP and NMPP groups. Furthermore, serum IL-18 expression was found to be significantly correlated with lgE, FeNO, IL-5, IL-8, and IL-13 concentrations. Significant differences were also observed between the MPP group and NMPP group patients in levels of IL-18, IL-5, and IL-6, and further ROC analysis showed that the area under the curve (AUC) of IL-18 and IL-5 were 0.813 (95% CI: 0.710–0.917; P<0.01) and 0.844 (95% CI: 0.756–0.933; P<0.01), respectively.

Conclusions

IL-18, IL-33, IFN-γ, IL-5, IL-6, IL-8, and IL-13 serum levels showed significant differences in children with CAP. IL-18 and IL-5 were much higher in the MPP group compared to the NMPP group patients, whereas IL-6 levels were significantly lower in these 2 groups.

Anti-Inflammatory Effects of Neochlorogenic Acid Extract from Mulberry Leaf (Morus alba L.) Against LPS-Stimulated Inflammatory Response through Mediating the AMPK/Nrf2 Signaling Pathway in A549 Cells

Neochlorogenic acid (nCGA) is a phenolic compound isolated from mulberry leaf (Morus alba L.), which possesses multiple pharmacological activities containing antioxidant and anti-inflammatory effects. However, the role of nCGA in the treatment of acute pneumonia and the underlying molecular mechanism are still unclear. Hence, the aim of study is to investigate the anti-inflammatory properties of nCGA on LPS-stimulated inflammation in A549 cells. In the present study, results reported that nCGA without cytotoxicity significantly reduced the production of TNF-α, IL-6, and NO, and further suppressed the proteins of iNOS, COX2, TNF-α, IL-6 expression. Furthermore, nCGA also inhibited NF-κB activation and blocked MAPKs signaling pathway phosphorylation. In addition, we found nCGA significantly increased the expression of HO-1 via activating the AMPK/Nrf2 signaling pathway to attenuate the inflammatory response, whereas this protective effect of nCGA was reversed by pre-treatment with compound C (C.C, an AMPK inhibitor). Therefore, all these results indicated that nCGA might act as a natural anti-inflammatory agent for the treatment of acute pneumonia.

Childhood pneumonia in low-and-middle-income countries: An update

OBJECTIVES

To review epidemiology, aetiology and management of childhood pneumonia in low-and-middle-income countries.

DESIGN

Review of published English literature between 2013 and 2019.

RESULTS

Pneumonia remains a major cause of morbidity and mortality. Risk factors include young age, malnutrition, immunosuppression, tobacco smoke or air pollution exposure. Better methods for specimen collection and molecular diagnostics have improved microbiological diagnosis, indicating that pneumonia results from several organisms interacting. Induced sputum increases microbiologic yield for Bordetella pertussis or Mycobacterium tuberculosis, which has been associated with pneumonia in high TB prevalence areas. The proportion of cases due to Streptococcus pneumoniae and Haemophilus influenzae b has declined with new conjugate vaccines; Staphylococcus aureus and H. influenzae non-type b are the commonest bacterial pathogens; viruses are the most common pathogens. Effective interventions comprise antibiotics, oxygen and non-invasive ventilation. New vaccines have reduced severity and incidence of disease, but disparities exist in uptake.

CONCLUSION

Morbidity and mortality from childhood pneumonia has decreased but a considerable preventable burden remains. Widespread implementation of available, effective interventions and development of novel strategies are needed.