The effect of black coral extraction on acute lung inflammation induced by cigarette smoke in mice

The protective effects of medicinal plants against cigarette smoking: A comprehensive review

BACKGROUNDS

Cigarette smoking remains a pervasive and harmful habit, and it poses a significant public health concern globally. Tobacco smoke contains numerous toxicants and carcinogens that contribute to the incidence of various diseases, including respiratory ailments, cancer, and cardiovascular disorders. Over the past decade, there has been a growing interest in exploring natural remedies to mitigate the harmful effects of cigarette smoke (CS). Medicinal plants, with their rich phytochemical compositions, have emerged as potential sources of protective agents against CS-induced damage.

OBJECTIVES

The current review attempts to comprehensively review and provide a thorough analysis of the protective effects of medicinal plants, including ginseng, Aloe vera, Olea europaea, Zea mays, green tea, etc. against CS-related toxicities.

MATERIALS AND METHODS

A comprehensive research and compilation of existing literature were conducted. We conducted a literature search using the Web of Science, PubMed, Scopus, and Google Scholar. We selected articles published in English between 1987 and 2025. The search was performed using keywords including cigarette smoking, cigarette smokers, second-hand smokers, natural compounds, plant extracts, naturally derived products, natural resources, phytochemicals, and medicinal plants.

RESULTS

This review critically investigated recent literature focusing on the effects of medicinal plant extracts, essential oils, and isolated compounds on reducing the adverse consequences of CS exposure. These investigations encompassed several in vivo, in vitro, and clinical trials, clarifying the mechanisms underlying the protective effects of these plants. The notable antioxidant, anti-inflammatory, and detoxifying properties of these botanical interventions were also highlighted.

CONCLUSION

Collectively, this review emphasizes the potential of medicinal plants in alleviating the harmful effects of CS. The rich active constituents present in these plants offer various mechanisms that counteract oxidative stress, inflammation, and carcinogenesis induced by CS exposure. Further research is warranted to reveal the precise molecular mechanisms, derive dosing recommendations, and explore the efficacy of botanical interventions in large-scale clinical trials, ultimately improving public health outcomes and providing valuable insights for the smoking population worldwide.

Establishment and comparison of Actinobacillus pleuropneumoniae experimental infection model in mice and piglets

Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia, a disease responsible for substantial losses in the worldwide pig industry. In this study, outbred Kunming (KM) and Institute of Cancer Research (ICR) mice were evaluated as alternative mice models for APP research. After intranasal infection of serotype 5 reference strain L20, there was less lung damage and a lower clinical sign score in ICR compared to KM mice. However, ICR mice showed more obvious changes in body weight loss, the amount of immune cells (such as neutrophils and lymphocytes) and cytokines (such as IL-6, IL-1β and TNF-α) in blood and bronchoalveolar lavage fluid (BALF). The immunological changes observed in ICR mice closely mimicked those found in piglets infected with L20. While both ICR and KM mice are susceptible to APP and induce pathological lesions, we suggest that ICR and KM mice are more suitable for immunological and pathogenesis studies, respectively. The research lays the theoretical basis for determine that mice could replace pigs as the APP infection model and it is of significance for the study of APP infection in the laboratory.

RTP801 Amplifies Nicotinamide Adenine Dinucleotide Phosphate Oxidase-4-Dependent Oxidative Stress Induced by Cigarette Smoke

Tobacco smoke (TS) causes chronic obstructive pulmonary disease, including chronic bronchitis, emphysema, and asthma. Rtp801, an inhibitor of mechanistic target of rapamycin, is induced by oxidative stress triggered by TS. Its up-regulation drives lung susceptibility to TS injury by enhancing inflammation and alveolar destruction. We postulated that Rtp801 is not only increased by reactive oxygen species (ROS) in TS but also instrumental in creating a feedforward process leading to amplification of endogenous ROS generation. We used cigarette smoke extract (CSE) to model the effect of TS in wild-type (Wt) and knockout (KO-Rtp801) mouse lung fibroblasts (MLF). The production of superoxide anion in KO-Rtp801 MLF was lower than that in Rtp801 Wt cells after CSE treatment, and it was inhibited in Wt MLF by silencing nicotinamide adenine dinucleotide phosphate oxidase-4 (Nox4) expression with small interfering Nox4 RNA. We observed a cytoplasmic location of ROS formation by real-time redox changes using reduction-oxidation-sensitive green fluorescent protein profluorescent probes. Both the superoxide production and the increase in the cytoplasmic redox were inhibited by apocynin. Reduction in the activity of Sod and decreases in the expression of Sod2 and Gpx1 genes were associated with Rtp801 CSE induction. The ROS produced by Nox4 in conjunction with the decrease in cellular antioxidant enzymatic defenses may account for the observed cytoplasmic redox changes and cellular damage caused by TS.

Development and systematic oxidative stress of a rat model of chronic bronchitis and emphysema induced by biomass smoke

BACKGROUND

Epidemiological research and meta-analyses of published data have shown that biomass smoke (BS) is a risk factor for chronic obstructive pulmonary disease (COPD). However, the link between BS and COPD lacks experimental confirmation.

OBJECTIVES

To verify whether BS can induce pathologic changes and systemic oxidative stress, which may be relevant to the development of emphysema and chronic bronchitis in rats.

METHODS

Rats were exposed to BS, cigarette smoke (CS), or clean air (sham) for 14 weeks. During the exposure, the O2, SO2, and CO levels were monitored. Pathological changes in the lungs, systemic oxidative stress, and inflammation biomarkers, together with GSTM1 and GSTP1 mRNA expression in the lung were measured. The glutamate-cysteine ligase catalytic subunit (GCLC) protein expression in the lung was measured using immunohistochemistry and western blotting.

RESULTS

The O2, CO, and SO2 levels were 20.31 ± 0.03%, 981.72 ± 64.76, and 2.59 ± 0.26 mg/m(3) for the BS group, respectively, while their levels in the CS group were 20.28 ± 0.15%, 745.56 ± 30.83, and 12.64 ± 0.591 mg/m(3) respectively. As with the rats exposed to CS, the BS rats showed an increased number of inflammatory cells in the bronchoalveolar lavage fluid, an increased pulmonary mean linear intercept and a decreased pulmonary mean alveolar number. Characteristics of chronic bronchitis and peribronchial fibrosis were also found in the BS-exposed rat lungs. Reduced body weight, systemic oxidative stress, and increased GCLC protein expression in the lungs were observed in the rats exposed to BS and CS.

CONCLUSIONS

BS can cause emphysema and chronic bronchitis similar to that caused by CS, which is accompanied by systemic oxidative stress and inflammation.