Comparisons of acute inflammatory responses of nose-only inhalation and intratracheal instillation of ammonia in rats

Revealing the "Yin-Jing" mystery veil of Platycodon grandiflorum by potentiating therapeutic effects and lung-oriented guidance property

ETHNIC PHARMACOLOGICAL RELEVANCE: "Yin-Jing" medicine (YJM) has been widely used by both ancient and modern Chinese medicine practitioners during long-term clinical practice. However, it remains unclear how to best guide other medicines to the targeted organs in a traditional Chinese medicine (TCM) prescription. Here, in an attempt to explain the scientific connotation of the YJM property (YJMP) attributed to a basic TCM theory, Platycodon grandiflorum (PG) was chosen as a case study to reveal the mystery of YJMP theory.

AIM OF THE STUDY

The main purpose of this study is to employ modern chemical and molecular biology methods to confirm the "Yin-Jing" effect of PG, and further clarify its material basis and related possible mechanism.

MATERIALS AND METHODS

The ammonia-induced lung injury rat model was utilized to determine the optimal dosage of traditional prescription Hui Yan Zhu Yu decoction (HYZYD) using Wright Giemsa staining, HE staining, Masson staining, and TUNEL analysis. With the same way, PG was confirmed to have potentiating therapeutic effect (PTE) by comparison with HYZYD and [HYZYD-PG]. TMT proteomics was used to reveal the "Yin-Jing" mechanism of action. Western blot assay (WB) was employed for verification of differentially expressed proteins. Additionally, four non-crossing fragmentations (Fr. A-D) were characterized by RPLC/SEC-ELSD and HILIC-ESI--Q-OT-IT-MS techniques. The PTE and guidance property assays were utilized to evaluate "Yin-Jing" functions by a compatible combination of hydroxysafflor yellow A (HYA) using qPCR, FCM, WB, HPLC, high content cell imaging (HCI) and high-resolution live-cell imaging (HRLCI) techniques.

RESULTS

The HYZYD-M (medium dose group) significantly improved the lung injury level in a pneumonia model of rats. PG enhanced the therapeutic effect of HYZYD ascribed to Yin-Jing PTE functions. TMT proteomics revealed a category of differentially expressed proteins ascribed to Golgi-ER between HYZYD and [HYZYD-PG]. Fr. C (i.e., saponins) and Fr. D (i.e., lipids) were determined as therapeutic fragmentations via the LPS-induced A549 cell injury model; however, Fr. B (fructooligosaccharides and small Mw fructans) had no therapeutic effect. Further compatibility PTE assays confirmed Fr. B significantly improved efficiency by a combination of HYA. The guidance assays showed Fr. B could significantly increase the uptake and distribution of HYA into lung cells and tissues. HCI assays showed that Fr. B increased uptake of HYA accompanied by significant activation of Golgi-ER. Unlike Fr. B, HRLCI showed that Fr. A, C and D were not only unobvious activations of Golgi-ER but also insignificant facilitation of colocalizations between HYA and Golgi-ER.

CONCLUSIONS

Fr. B is believed to be a key YJMP material basis of PG attributed to Yin-Jing PTE with characteristic of lung-oriented guidance property, whereas another abound Fr. C was determined to have synergistic effects rather than Yin-Jing material basis.

Countermeasures against Pulmonary Threat Agents

Inhaled toxicants are used for diverse purposes, ranging from industrial applications such as agriculture, sanitation, and fumigation to crowd control and chemical warfare, and acute exposure can induce lasting respiratory complications. The intentional release of chemical warfare agents (CWAs) during World War I caused life-long damage for survivors, and CWA use is outlawed by international treaties. However, in the past two decades, chemical warfare use has surged in the Middle East and Eastern Europe, with a shift toward lung toxicants. The potential use of industrial and agricultural chemicals in rogue activities is a major concern as they are often stored and transported near populated areas, where intentional or accidental release can cause severe injuries and fatalities. Despite laws and regulatory agencies that regulate use, storage, transport, emissions, and disposal, inhalational exposures continue to cause lasting lung injury. Industrial irritants (e.g., ammonia) aggravate the upper respiratory tract, causing pneumonitis, bronchoconstriction, and dyspnea. Irritant gases (e.g., acrolein, chloropicrin) affect epithelial barrier integrity and cause tissue damage through reactive intermediates or by direct adduction of cysteine-rich proteins. Symptoms of CWAs (e.g., chlorine gas, phosgene, sulfur mustard) progress from airway obstruction and pulmonary edema to acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), which results in respiratory depression days later. Emergency treatment is limited to supportive care using bronchodilators to control airway constriction and rescue with mechanical ventilation to improve gas exchange. Complications from acute exposure can promote obstructive lung disease and/or pulmonary fibrosis, which require long-term clinical care. SIGNIFICANCE STATEMENT: Inhaled chemical threats are of growing concern in both civilian and military settings, and there is an increased need to reduce acute lung injury and delayed clinical complications from exposures. This minireview highlights our current understanding of acute toxicity and pathophysiology of a select number of chemicals of concern. It discusses potential early-stage therapeutic development as well as challenges in developing countermeasures applicable for administration in mass casualty situations.

Protective role of selenium on ammonia-mediated nephrotoxicity via PI3K/AKT/mTOR pathway: Crosstalk between autophagy and cytokine release

Ammonia (NH₃) is a hazardous substance to human and animal health. Selenium (Se) is an essential micronutrient with multiple health benefits. The present study aimed to verify whether and how Se supplementation has a protective role against NH₃ mediated-nephrotoxicity in pigs. A Se-NH₃ interaction model was established in pigs and the kidney samples were collected after a 30-day treatment period. The results showed that NH₃ exposure inhibited the PI3K/AKT/mTOR pathway and enhanced the secretion of inflammatory cytokines to induce autophagy and inflammation. Se can regulate the PI3K/AKT/mTOR pathway and attenuate the secretion of inflammatory cytokines altered by NH₃ to reduce autophagy and inflammation. In addition, Se co-treatment inhibited ROS production, elevated the activities of antioxidant systems, and increased the expression of 13 selenoproteins in pig kidneys caused by NH₃ exposure. These results implied that L-selenomethionine can moderate NH₃-induced nephrotoxicity in pigs. Our study gives new ideas for the specific mechanism of NH₃ nephrotoxicity and provides a reference for comparative medicine and clinical medication.

Ammonia exposure by intratracheal instillation causes severe and deteriorating lung injury and vascular effects in mice

OBJECTIVE

Ammonia (NH₃) is a corrosive alkaline gas that can cause life-threatening injuries by inhalation. The aim was to establish a disease model for NH₃-induced injuries similar to acute lung injury (ALI) described in exposed humans and investigate the progression of lung damage, respiratory dysfunction and evaluate biomarkers for ALI and inflammation over time.

METHODS

Female BALB/c mice were exposed to an NH₃ dose of 91.0 mg/kg·bw using intratracheal instillation and the pathological changes were followed for up to 7 days.

RESULTS

NH₃ instillation resulted in the loss of body weight along with a significant increase in pro-inflammatory mediators in both bronchoalveolar lavage fluid (e.g. IL-1β, IL-6, KC, MMP-9, SP-D) and blood (e.g. IL-6, Fibrinogen, PAI-1, PF4/CXCL4, SP-D), neutrophilic lung inflammation, alveolar damage, increased peripheral airway resistance and methacholine-induced airway hyperresponsiveness compared to controls at 20 h. On day 7 after exposure, deteriorating pathological changes such as increased macrophage lung infiltration, heart weights, lung hemorrhages and coagulation abnormalities (elevated plasma levels of PAI-1, fibrinogen, endothelin and thrombomodulin) were observed but no increase in lung collagen. Some of the analyzed blood biomarkers (e.g. RAGE, IL-1β) were unaffected despite severe ALI and may not be significant for NH₃-induced damages.

CONCLUSIONS

NH₃ induces severe acute lung injuries that deteriorate over time and biomarkers in lungs and blood that are similar to those found in humans. Therefore, this model has potential use for developing diagnostic tools for NH₃-induced ALI and for finding new therapeutic treatments, since no specific antidote has been identified yet.

High concentrations of ammonia induced cytotoxicity and bronchoconstriction in a precision-cut lung slices rat model

Exposure to high concentrations of ammonia (NH3) can cause life-threatening lung damages. The objective of this study was to establish a translational in vitro model for NH3-induced lung injury. Precision-cut lung slices (PCLS) from rats were exposed to NH3 and toxicological responses and cell viability were quantified by analysis of LDH, WST-1, inflammatory mediators (IL-1β, IL-6, CINC-1, MMP-9, RAGE and IL-18), and by microscopic evaluation of bronchoconstriction induced by electric-field-stimulation (EFS) or methacholine (MCh). Different treatment strategies were assessed to prevent or reverse the damages caused by NH3 using anti-inflammatory, anti-oxidant or neurologically active drugs. Exposure to NH3 caused a concentration-dependent increase in cytotoxicity (LDH/WST-1) and IL-1β release in PCLS medium. None of the treatments reduced cytotoxicity. Deposition of NH3 (24-59 mM) on untreated PCLS elicited an immediate concentration-dependent bronchoconstriction. Unlike MCh, the EFS method did not constrict the airways in PCLS at 5 h after NH3-exposure (47-59 mM). Atropine and TRP-channel antagonists blocked EFS-induced bronchoconstriction but these inhibitors could not block the immediate NH3-induced bronchoconstriction. In conclusion, NH3 exposure caused cytotoxic effects and lung damages in a concentration-dependent manner and this PCLS method offers a way to identify and test new concepts of medical treatments and biomarkers that may be of prognostic value.

Dynamic Changes in Lung Microbiota of Broilers in Response to Aging and Ammonia Stress

Comprehensive microbial analysis has revealed that the lung harbors a complex variety of microbiota, and although the dynamic distribution of the lung microbiota in mice and laying hens of different ages is well established, this distribution has not been clarified in broilers of different ages. Here, we performed 16S rRNA gene sequencing of lung lavage fluid from broilers at 3 (3D), 7 (7D), 14 (14D), 21 (21D), and 35 (35D) days of age to evaluate changes in the composition of their lung microbiota. Upon examination of the composition and function of the broiler lung microbiota, we found that their maturation increased significantly with age. Specifically, the microbiota composition was similar between 7 and 14D and between 21 and 35D. The relative abundance of aerobic bacteria in the broiler lungs gradually increased as the broilers developed, whereas the relative abundance of potentially pathogenic bacteria reached its highest level at 3D. The relative abundance of predicted functions in microbiota was very similar among 3, 7, and 14D, whereas the Glycan Biosynthesis and Metabolism pathway in microbiota was enriched at 21D. These findings suggest that these metabolic pathways play critical roles in shaping broiler microbiota at these age stages. In addition, short-term external ammonia stimulation significantly increased lung inflammation but did not significantly affect the lung microbiota. Taken together, these data reveal the dynamics of age-related changes in the microbiota of broiler lungs and the stability (the significant variation in the microbial composition) of these microbial communities in response to short-term ammonia stress. These findings provide new insights into the development of broiler lung microbiota and serve as a reference for subsequent studies to evaluate disease prevention in broilers subjected to large-scale breeding.