Protective Effects of Platycodin D3 on Airway Remodeling and Inflammation via Modulating MAPK/NF-κB Signaling Pathway in Asthma Mice

The anti-inflammatory effects of saponins from natural herbs

Inflammation is a protective mechanism that also starts the healing process. However, inflammatory reaction may cause severe tissue damage. The increased influx of phagocytic leukocytes may produce excessive amount of reactive oxygen species, which leads to additional cell injury. Inflammatory response activates the leukocytes and thus induces tissue damage and prolongs inflammation. The inflammation-induced activation of the complement system may also contribute to cell injury. Non-steroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids are chief agents for treating inflammation associated with the diseases. However, the unwanted side effects of NSAIDs (e.g., gastrointestinal disturbances, skin reactions, adverse renal effects, cardiovascular side effects) and glucocorticoids (e.g., suppression of immune system, Cushing's syndrome, osteoporosis, hyperglycemia) limit their use in patients. Natural herbs are important sources of anti-inflammatory drugs. The ingredients extracted from natural herbs display anti-inflammatory effects to work through multiple pathways with lower risk of adverse reaction. At present, the main anti-inflammatory natural agents include saponins, flavonoids, alkaloids, polysaccharides, and so on. The present article will review the anti-inflammatory effects of saponins including escin, ginsenosides, glycyrrhizin, astragaloside, Panax notoginseng saponins, saikosaponin, platycodin, timosaponin, ophiopogonin D, dioscin, senegenin.

Atomized inhalation of Icaritin reduces airway inflammation and remodeling in asthmatic mice

BACKGROUND

Asthma is a disease characterized by airway hyperresponsiveness and airway inflammation. Icaritin (ICT) is a plant hormone with various pharmacological activities such as anti-inflammatory, immune regulation, and anti-tumor. This study mainly explored the effects of nebulized inhalation of ICT on airway inflammation and airway remodeling in asthmatic mice.

METHOD

Different groups of ovalbumin (OVA)-induced asthma mice with acute and chronic airway inflammation received ICT. Asthmatic mice received budesonide (BDND) aerosol inhalation as a positive control, while normal control and asthma model mice received the same volume of saline. Following finishing of the study, analyses were conducted on behavioral tests, biochemical indices, and histological structures of lung tissues.

RESULTS

Aerosol inhalation of ICT can notably reduce inflammatory cells infiltration around the airways and pulmonary vessels, and suppressed goblet cell hyperplasia in asthmatic mice. Long-term inhalation of ICT can decrease airway collagen deposition and airway smooth muscle hyperplasia, and alleviate airway hyperresponsiveness, mirroring the effects observed with hormone employed in clinical practice.

CONCLUSION

Nebulized inhalation of ICT can effectively inhibit airway inflammation in asthmatic mice, improve airway remodeling, and reduce airway hyperresponsiveness, with effects similar to those of hormones. It may serve as a potential candidate used as a hormone replacement asthma treatment.

The pharmacology and mechanisms of platycodin D, an active triterpenoid saponin from Platycodon grandiflorus

Chinese doctors widely prescribed Platycodon grandiflorus A. DC. (PG) to treat lung carbuncles in ancient China. Modern clinical experiences have demonstrated that PG plays a crucial role in treating chronic pharyngitis, plum pneumonia, pneumoconiosis, acute and chronic laryngitis, and so forth. Additionally, PG is a food with a long history in China, Japan, and Korea. Furthermore, Platycodin D (PLD), an oleanane-type triterpenoid saponin, is one of the active substances in PG. PLD has been revealed to have anti-inflammatory, anti-viral, anti-oxidation, anti-obesity, anticoagulant, spermicidal, anti-tumor etc., activities. And the mechanism of the effects draws lots of attention, with various signaling pathways involved in these processes. Additionally, research on PLD's pharmacokinetics and extraction processes is under study. The bioavailability of PLD could be improved by being prescribed with Glycyrrhiza uralensis Fisch. or by creating a new dosage form. PLD has been recently considered to have the potential to be a solubilizer or an immunologic adjuvant. Meanwhile, PLD was discovered to have hemolytic activity correlated. PLD has broad application prospects and reveals practical pharmacological activities in pre-clinical research. The authors believe that these activities of PLD contribute to the efficacy of PG. What is apparent is that the clinical translation of PLD still has a long way to go. With the help of modern technology, the scope of clinical applications of PLD is probable to be expanded from traditional applications to new fields.

Leonotis nepetifolia Transformed Root Extract Reduces Pro-Inflammatory Cytokines and Promotes Tissue Repair In Vitro

Inflammation is closely related to asthma and its defining feature: airway remodeling. The aim of this study was to determine the effects of extracts of normal (NR) and transformed (TR) Leonotis nepetifolia roots on respiratory cells and against the gingival epithelium. Extracts from NR and TR roots were added to lung fibroblast, bronchial epithelial and gingival fibroblast cell lines, in the presence of HRV-16 infection, to determine their impact on inflammation. The expression of inflammatory cytokines (IL-6, IL-1β, GM-CSF and MCAF) as well as total thiol contents were assessed. The TR extract inhibited rhinovirus-induced IL-6 and IL-1β expression in all tested airway cells (p < 0.05). Additionally, the extract decreased GM-CSF expression in bronchial epithelial cells. The tested extracts had positive effects on total thiol content in all tested cell lines. The TR root extract demonstrated wound healing potential. While both tested extracts exhibited anti-inflammatory and antioxidative effects, they were stronger for the TR extract, possibly due to higher concentrations of beneficial metabolites such as phenols and flavonoids. Additionally, wound healing activity was demonstrated for the TR root extract. These results suggest that TR root extract may become a promising therapeutic agent in the future.