Mechanism of action of certain medicinal plants for the treatment of asthma

Traditional Herbal Plants and their Phytoconstituents Based Remedies for Respiratory Diseases: A Review

Despite medical science advancements in recent years, pulmonary diseases are still hard to control and can be potentially life-threatening. These include asthma, COPD, lung cancer, cystic fibrosis, pneumonia, pleurisy, and sarcoidosis. These illnesses often cause severe breathing problems, which can be fatal if not treated properly. While some chemical drugs are used to treat these conditions, they can cause side effects and are not always effective. Herbal medicine offers an alternative treatment option with fewer side effects and has shown promise in treating respiratory issues. Certain medicinal plants, such as garlic (Allium sativum), hawthorn (Crataegus rhipidophylla), moringa (Moringa oleifera), and ashwagandha (Withania somnifera), may help manage lung diseases. Natural compounds found in plants, like apple polyphenol, ligustrazine, salidroside, resveratrol, and quercetin, can also help reduce symptoms. These plants and compounds work by reducing cell overgrowth, fighting oxidative stress, lowering inflammation, stopping tumor growth, improving blood flow, and relaxing the airways. This review outlines the types of plants and compounds that can be utilized in treating pulmonary conditions, along with their respective mechanisms of action.

Nanotechnology-Based Therapeutics for Airway Inflammatory Diseases

Under the concept of "one airway, one disease", upper and lower airway inflammatory diseases share similar pathogenic mechanisms and are collectively referred to as airway inflammatory diseases. With industrial development and environmental changes, the incidence of these diseases has gradually increased. Traditional treatments, including glucocorticoids, antihistamines, and bronchodilators, have alleviated much of the discomfort experienced by patients. However, conventional drug delivery routes have inherent flaws, such as significant side effects, irritation of the respiratory mucosa, and issues related to drug deactivation. In recent years, nanomaterials have emerged as excellent carriers for drug delivery and are being increasingly utilized in the treatment of airway inflammatory diseases. These materials not only optimize the delivery of traditional medications but also facilitate the administration of various new drugs that target novel pathways, thereby enhancing the treatment outcomes of inflammatory diseases. This study reviews the latest research on nano-drug delivery systems used in the treatment of airway inflammatory diseases, covering traditional drugs, immunotherapy drugs, antimicrobial drugs, plant-derived drugs, and RNA drugs. The challenges involved in developing nano-delivery systems for these diseases are discussed, along with a future outlook. This review offers new insights that researchers can utilize to advance further research into the clinical application of nano-drug delivery systems for treating airway inflammatory diseases.

The interplay of plant-based antioxidants, inflammation, and clinical outcomes in asthma: A systematic review

BACKGROUND

Asthma is a chronic inflammatory disease and a leading cause of disability, posing a huge economic and social burden. Plant-based antioxidants have the potential to block proinflammatory pathways and protect against oxidative damage, which could improve asthma management.

OBJECTIVE

This review examines the role of plant-based antioxidants as adjuvant therapy on inflammatory markers and clinical outcomes of adults with asthma.

METHODS

Digital databases, including Scopus, MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Airway Group's Specialized Register of Trials, were searched. Two independent authors performed initial and full-text screening of identified papers. The criteria for study inclusion and exclusion were predefined. Two authors independently performed data extraction and risk of bias as per the PRISMA checklist.

RESULTS

After full-text screening, nine randomized controlled trials were included in the final review. Seven of the included studies highlighted the efficacy of plant-based antioxidants in modulating the inflammatory cytokines in asthmatics. The benefits of antioxidants were also observed for improving oxidative status, lung functioning, and airway inflammatory markers. Furthermore, the overall quality of asthmatic patients' lives was improved with fewer exacerbations such as night coughs and wheezing. Despite having some limitations, the overall risk of bias was low in this review.

CONCLUSION

The review indicated that plant-based antioxidants could have adjuvant beneficial effects in the management of asthma inflammatory markers, which may help improve asthma-related clinical outcomes. However, due to the small number of study subjects, further research is required on the effect of plant-based antioxidants on asthma-inflammatory markers and clinical outcomes.

Sodium houttuyfonate modulates the lung Th1/Th2 balance and gut microbiota to protect against pathological changes in lung of ovalbumin-induced asthmatic mice

OBJECTIVE

The gut-lung axis involves microbial and product interactions between the lung and intestine. Antibiotics for chronic asthma can cause intestinal dysbiosis, disrupting this axis. Sodium houttuyfonate (SH) has diverse biological activities, including modifying gut microbiota, antibacterial, and anti-inflammatory. This study aims to explore the relationship between SH, CD4+ T cells, and gut microbiota.

METHODS

Allergic asthma was experimentally induced in mice through injection and inhalation of ovalbumin. After the administration of different amounts of SH, ELISA was utilized to ascertain the levels of inflammatory cytokines in the serum, flow cytometry was used to examine the levels of Th1/Th2 cytokines in CD4+ cells from lung tissues. The expression of T-bet and GATA3 in lung tissue was determined by Western blotting and quantitative real-time PCR assay. Gut microbiota was determined by 16S rRNA gene sequencing.

RESULTS

The results showed that SH can alleviate pulmonary injury in asthmatic mice, reducing serum levels of IL-4, IL-5, and IL-13 while simultaneously increasing IFN-γ. Furthermore, SH has been observed to modulate the balance of Th1/Th2 cells by up-regulating the mRNA and protein expression of T-bet but down-regulating GATA3 in the lung tissues of asthmatic mice, thereby promoting the differentiation of Th1 cells. Additionally, SH can regulate the variety and composition of gut microbiota especially genus Akkermansia in asthmatic mice.

CONCLUSION

SH can alleviate asthma through the regulation of Th1/Th2 cells and gut microbiota.

Luteolin alleviates airway remodeling in asthma by inhibiting the epithelial-mesenchymal transition via β-catenin regulation

BACKGROUND

Asthma is a prevalent long-term inflammatory condition that causes airway inflammation and remodeling. Increasing evidence indicates that epithelial-mesenchymal transition (EMT) holds a prominent implication in airway reconstruction in patients with asthma. Flavonoids obtained from Chinese Materia Medica (CMM), such as Luteolin (Lut), exhibit various beneficial effects in various asthma models. Lut has been shown to mitigate various asthma symptoms, including airway inflammation, hyperresponsiveness, bronchoconstriction, excessive mucus production, pulmonary autophagy, and neutrophilic asthma. However, whether flavonoids can suppress EMT-associated airway remodeling in asthma and the fundamental mechanisms involved remain unclear, with no studies specifically addressing Lut in this context.

PURPOSE

To evaluate the inhibition of airway remodeling in asthma by Lut and its potential mechanisms, while examining the significance of β-catenin in this process through cellular and animal studies.

METHODS

A BEAS-2B cell model stimulated by lipopolysaccharide (LPS) was established in vitro. Wound closure and Transwell assays were utilized to assess the cellular migratory ability. EMT- and fibrosis-related markers in LPS-stimulated cells were evaluated using RT-qPCR and western blotting. The status of the β-catenin/E-cadherin and β-catenin destruction complexes was evaluated using western blotting, immunofluorescence (IF) staining, and co-immunoprecipitation (Co-IP) analysis. The regulatory function of Lut in β-catenin-dependent EMT was further validated by β-catenin overexpression with adenovirus transduction and siRNA-mediated knockdown of β-catenin. Moreover, the counts of different types of bronchoalveolar lavage fluid (BALF) inflammatory cells from mice with asthma induced by ovalbumin (OVA) were evaluated in vivo using Congo red staining. Hematoxylin and eosin (H&E), Masson's trichrome, and periodic acid-Schiff (PAS) staining were used to evaluate collagen deposition, mucus production, and inflammation in murine lung tissues. Western blotting and immunohistochemistry (IHC) assays were used to assess EMT- and fibrosis-related markers in the lung tissues in vivo.

RESULT

Six naturally derived flavonoids, including Lut, attenuated cell migration and prevented EMT in LPS-treated BEAS-2B cells. Moreover, Lut suppressed TGF-β1, MMP-9, fibronectin (FN), and α-smooth muscle actin (α-SMA) levels in LPS-stimulated BEAS-2B cells. Additionally, Lut downregulated the levels of β-catenin by modulating the β-catenin/E-cadherin and β-catenin destruction complexes, highlighting the pivotal role of β-catenin in EMT inhibition by Lut in LPS-stimulated BEAS-2B cells. Furthermore, Lut suppressed airway inflammation and attenuated EMT-associated airway remodeling through β-catenin blockade in OVA-induced asthmatic mice. The bronchial wall thickness notably reduced from 37.24 ± 4.00 μm in the asthmatic model group to 30.06 ± 4.40 μm in the Lut low-dose group and 24.69 ± 2.87 μm in the Lut high-dose group.

CONCLUSION

According to our current understanding, this research is the first to reveal that Lut diminishes airway remodeling in asthma by inhibiting EMT via β-catenin regulation, thereby filling a research gap concerning Lut and flavonoids. These results provide a theoretical basis for treating asthma with anti-asthmatic CMM, as well as a candidate and complementary therapeutic approach to treat asthma.

Therapeutic potential of 18-β-glycyrrhetinic acid-loaded poly (lactic-co-glycolic acid) nanoparticles on cigarette smoke-induced in-vitro model of COPD

Chronic obstructive pulmonary disease (COPD) is strongly linked to cigarette smoke, which contains toxins that induce oxidative stress and airway inflammation, ultimately leading to premature airway epithelial cell senescence and exacerbating COPD progression. Current treatments for COPD are symptomatic and hampered by limited efficacy and severe side effects. This highlights the need to search for an optimal therapeutic candidate to address the root causes of these conditions. This study investigates the possible potential of poly (lactic-co-glycolic acid) (PLGA)-based nanoparticles encapsulating the plant-based bioactive compound 18-β-glycyrrhetinic acid (18βGA) as a strategy to intervene in cigarette smoke extract (CSE)-induced oxidative stress, inflammation, and senescence, in vitro. We prepared 18βGA-PLGA nanoparticles, and assessed their effects on cell viability, reactive oxygen species (ROS) production, anti-senescence properties (expression of senescence-associated β galactosidase and p21 mRNA), and expression of pro-inflammatory genes (CXCL-1, IL-6, TNF-α) and inflammation-related proteins (IL-8, IL-15, RANTES, MIF). The highest non-toxic concentration of 18βGA-PLGA nanoparticles to healthy human broncho epithelial cell line BCiNS1.1 was identified as 5 µM. These nanoparticles effectively mitigated cigarette smoke-induced inflammation, reduced ROS production, protected against cellular aging, and counteracted the effects of CSE on the expression of the inflammation-related genes and proteins. This study underscores the potential of 18βGA encapsulated in PLGA nanoparticles as a promising therapeutic approach to alleviate cigarette smoke-induced oxidative stress, inflammation, and senescence. Further research is needed to explore the translational potential of these findings in clinical and in vivo settings.

Toxicological assessment of the Achyrocline satureioides aqueous extract in the Caenorhabditis elegans alternative model

Achyrocline satureioides, popularly called "marcela" in Brazil, is used in traditional medicine in South America. A. satureioides, inflorescences are used for many conditions, including to minimize the Sars-Cov-2 symptoms. Therefore, the aim of this study was to determine the toxicity profile of A. satureioides aqueous extract (ASAE), using the Caenorhabditis elegans (C. elegans) alternative model. Survival, reproduction, development, and transgenerational assays were performed. The effects of ASAE were investigated under conditions of thermal stress and presence of oxidant hydrogen peroxide (H2O2). In addition, C. elegans strains containing high antioxidant enzyme levels and elevated lineages of daf-16, skn-1 and daf-2 regulatory pathways were examined. The ASAE LC50 value was found to be 77.3 ± 4 mg/ml. The concentration of ASAE 10 mg/ml (frequently used in humans) did not exhibit a significant reduction in worm survival at either the L1 or L4 stage, after 24 or 72 hr treatment. ASAE did not markedly alter the body area. In N2 strain, ASAE (10 or 25 mg/ml) reversed the damage initiated by H2O2. In addition, ASAE protected the damage produced by H2O2 in strains containing significant levels of sod-3, gst-4 and ctl - 1,2,3, suggesting modulation in these antioxidant systems by this plant extract. ASAE exposure activated daf-16 and skn-1 stress response transcriptional pathways independently of daf-2, even under extreme stress. Data suggest that ASAE, at the concentrations tested in C. elegans, exhibits a reliable toxicity profile, which may contribute to consideration for safe use in humans.

Antiasthmatic Medicinal Plants of Tanzania: An Ethnomedicinal and Ethnopharmacological Review

Traditional medicinal plants (TMPs) are a significant part of people's quality of life, offering a natural substitute for modern drugs with numerous side effects. In Tanzania, data on antiasthmatic TMPs are highly fragmented. This review, a comprehensive compilation of ethnobotanical research evidence, aimed to provide a thorough understanding of TMPs used by the locals for asthma management and identify species that have already been investigated in preclinical studies. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. To gather relevant literature on antiasthmatic TMPs used by Tanzanians, a web search using electronic databases (Scopus, PubMed, ProQuest, Academic Library, Web of Science, SciFinder, Wiley Online Library, Google Scholar, ScienceDirect, and African Journals Online) was conducted. The scientific names were verified through the Plants of the World Online database, and the collected information was analysed for descriptive statistics using Microsoft Excel software. The ethnomedicinal information was obtained from 24 different articles. Microsoft Excel software was used to analyse the data using descriptive statistics. A total of 62 TMPs belonging to 33 families were identified. Species of the Fabaceae (14.5%) and Rubiaceae families (8.1%) are the most utilized. The analysis revealed that trees (42.0%) and leaves (40.0%) are the most utilized life forms and plant parts, respectively. Most plant materials (59.7%) used to make remedies were collected from the wild environment. Decoction (55.0%) is the dominant preparation method of remedies, and the majority (69.0%) were orally administered. Of the recorded TMPs, 22.6% had their in vivo antiasthmatic activity reported in the literature. The review also highlighted the strategic significance of preparations of remedies made from TMPs for discovering and developing new antiasthmatic drugs. However, the need to identify the molecular targets of action and toxicological aspects of the TMPs should be considered.

Mesenchymal Stem Cell-Derived Extracellular Vesicle Therapy for Asthma in Murine Models: A Systematic Review and Meta-analysis

BACKGROUND

Asthma is a common disease, and among the most predominant causes of the years lived with disability. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as a promising avenue for asthma management. The objective of this study is to perform a systematic review and meta-analysis of pre-clinical studies investigating the therapeutic use of MSC-EVs in murine models of asthma.

METHODS

A systematic search of electronic databases was performed. Meta-analyses were conducted on broncho-alveolar lavage fluid (BALF) cells and cytokines, as well as airway hyper-responsiveness Penh values and histological staining scores to determine the efficacy of MSC-EVs-based therapy, comparing treated rodents with untreated ones. BALF IL-4, BALF total cells, and BALF eosinophils were chosen as the primary outcomes, while airway hyper-responsiveness Penh values, BALF cytokines excluding IL-4, and histological staining scores were chosen as secondary outcomes.

RESULTS

A total of 19 eligible studies were included in the current systematic review, with 9 assessing BALF IL-4, 11 assessing BALF total cells, and 10 assessing BALF eosinophils. Pooled Hedges' g (p-value) for each outcome was - 4.407 (< 0.001), -4.976 (< 0.001), and - 4.071 (< 0.001), showing that MSC-EVs therapy inhibits asthma pathology. Changes in secondary outcomes also indicated a reduction in inflammation, goblet cell hyperplasia, and airway hyper-responsiveness. Subgroup analyses did not reveal significant disparities between the type of rodents and administration routes, and meta-regressions were only significant for MSC-EVs source and dose in the IL-4 meta-analysis, and for administration frequency and time from the last challenge to sacrifice in the BALF total cell meta-analysis.

CONCLUSION

This review highlights the current pre-clinical evidence of MSC-EVs therapy for asthma and finds its application ameliorates multiple aspects of asthma's pathology. We further underline the importance of MSC-EVs source, dose, administration frequency, and timing on the therapeutic effect and warrant further investigation and clinical translation to assess the best treatment regimen and to gauge the efficacy of EV therapy in human asthma cases.

Baicalein glycymicelle ophthalmic solution: Preparation, in vitro antimicrobial activities, and antimicrobial mechanism evaluations

The purpose of this study was to develop a novel baicalein (BAI) loaded glycymicelle ophthalmic solution with small molecule phytochemical glycyrrhizin as nanocarriers and to explore this solution's potential as an antimicrobial agent against ocular infections. The optimized BAI glycymicelles had a high encapsulation efficiency (98.76 ± 1.25 %), a small particle size (54.38 ± 2.41 nm), a uniform size distribution (polydispersity index = 0.293 ± 0.083), and a zeta potential of -28.3 ± 1.17 mV. The BAI glycymicelle ophthalmic solution exhibited an excellent short-term storage stability. BAI glycymicelles significantly increased the apparent solubility and in vitro release capability of BAI. The BAI glycymicelle ophthalmic solution exhibited no hen's egg-chorioallantoic membrane' irritation and strong in vivo ocular tolerance in rabbits. The BAI glycymicelles noticeably enhanced the in vivo corneal permeation. The BAI glycymicelles also precipitated increased in vitro antioxidant activity and significantly improved in vitro antipathogen activities. Various antimicrobial mechanisms, including the destruction of the bacterial cell wall, damage to the bacterial cell membranes, interruptions to the biofilm structure, and the apoptosis of bacteria, were inflicted on BAI glycymicelles. These findings provided useful knowledge regarding the development of a novel ophthalmic solution and formulation of BAI.

Dietary restriction-induced alterations on estrogen receptor alpha expression in regulating fertility in male Coturnix coturnix japonica: Relevance of Withania somnifera in modulation of inflammation and oxidative stress in testis

PROBLEM

Reproductive performance of animals gets affected by nutritional restrictions which act as potential stressors leading to hormonal imbalance and testicular inflammation, the major causes of infertility. Withania somnifera (WS), well-known traditional medicinal plant, has been used as antistress and infertility treatment. Therefore, the present study looks into the ameliorative effects of WS on the reproductive and immune system of male Coturnix coturnix japonica in stressed conditions like water and food restriction focussing on the modulation in estrogen receptor alpha (ERα).

METHOD OF STUDY

Biochemical estimations for oxidative stress, histological alterations, immuno-fluorescent localization of ERα, interleukin (IL)-1β, IL-4, and interferon gamma (IFN-γ) in testicular cells were performed.

RESULTS

Nutritional restriction declines endogenous estradiol, ERα in testicular cells while it elevates corticosterone leading to oxidative stress in testis thereby reducing fertility by decrease in sperm. Results indicate significant reversal in all the parameters after the administration of WS by improving testicular cell morphology, increased superoxide and catalase activity thus reducing oxidative stress. WS increases spermatogenesis and enhances expression of ERα in testicular cells in quail. Further, WS increases IL-4, decreases IL-1β and IFN-γ expression in testis, thereby improving immune profile contrary to stressed conditions.

CONCLUSION

WS stimulates HPG-axis even after stress resulting in increased endogenous estradiol which stimulates the expression of ERα in testis; increases sperm count and immunity thereby improving the reproductive performance. WS may be the best therapy against nutritional-restriction stress induced reproductive toxicity by reducing oxidative stress mediated inflammatory response via increased testicular expression of ERα in quail.

Phytochemicals as treatment for allergic asthma: Therapeutic effects and mechanisms of action

BACKGROUND

Allergic asthma is an inflammatory disease caused by the immune system's reaction to allergens, inflammation and narrowing of the airways, and the production of more than normal mucus. One of the main reasons is an increased production of inflammatory cytokines in the lungs that leads to the appearance of symptoms of asthma, including inflammation and shortness of breath. On the other hand, it has been proven that phytochemicals with their antioxidant and anti-inflammatory properties can be useful in improving allergic asthma.

PURPOSE

Common chemical treatments for allergic asthma include corticosteroids, which have many side effects and temporarily relieve symptoms but are not a cure. Therefore, taking the help of natural compounds to improve the quality of life of asthmatic patients can be a valuable issue that has been evaluated in the present review.

STUDY DESIGN AND METHODS

In this study, three databases (Scopus, PubMed, and Cochrane) with the keywords: allergic asthma, phytochemical, plant, and herb were evaluated. The primary result was 5307 articles. Non-English, repetitive, and review articles were deleted from the study.

RESULTS AND DISCUSSION

Finally, after carefully reading the articles, 102 were included in the study (2006-2022). The results of this review state that phytochemicals suppress the inflammatory pathways via inhibition of inflammatory cytokines production/secretion, genes, and proteins involved in the inflammation process, reducing oxidative stress indicators and symptoms of allergic asthma, such as cough and mucus production in the lungs.

CONCLUSION

With their antioxidant effects, this study concluded that phytochemicals suppress cytokines and other inflammatory indicators and thus can be considered an adjunctive treatment for improving allergic asthma.

Spice and Herb Frauds: Types, Incidence, and Detection: The State of the Art

There is a necessity to protect the quality and authenticity of herbs and spices because of the increase in the fraud and adulteration incidence during the last 30 years. There are several aspects that make herbs and spices quite vulnerable to fraud and adulteration, including their positive and desirable sensorial and health-related properties, the form in which they are sold, which is mostly powdered, and their economic relevance around the world, even in developing countries. For these reasons, sensitive, rapid, and reliable techniques are needed to verify the authenticity of these agri-food products and implement effective adulteration prevention measures. This review highlights why spices and herbs are highly valued ingredients, their economic importance, and the official quality schemes to protect their quality and authenticity. In addition to this, the type of frauds that can take place with spices and herbs have been disclosed, and the fraud incidence and an overview of scientific articles related to fraud and adulteration based on the Rapid Alert System Feed and Food (RASFF) and the Web of Science databases, respectively, during the last 30 years, is carried out here. Next, the methods used to detect adulterants in spices and herbs are reviewed, with DNA-based techniques and mainly spectroscopy and image analysis methods being the most recommended. Finally, the available adulteration prevention measurements for spices and herbs are presented, and future perspectives are also discussed.