Natural products in the treatment of pulmonary emphysema: Therapeutic effects and mechanisms of action

Bioactive Polyphenolic Compounds from Propolis of Tetragonula carbonaria in the Gibberagee Region, New South Wales, Australia

Stingless bee propolis has emerged globally as a new source of bioactive molecules that can advance human health. However, limited research has been conducted on Australian stingless bee propolis. This study investigated the chemical composition and biological activity of the propolis produced by the stingless bees Tetragonula carbonaria from Gibberagee, a distinct region of New South Wales state in Australia. Using bioassay-guided fractionation, twelve compounds were isolated, including six A-ring methylated flavonoids. Nine of these compounds demonstrated strong scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radicals, with five exhibiting greater potency than vitamin C. Chemical structures of seven additional minor flavonoids were determined through an intensive MS/MS data analysis. In silico screening of these 19 compounds revealed that all, except for gallic acid, displayed a higher binding affinity to α-glucosidase than the antidiabetic drug, voglibose. This study showed that the Gibberagee stingless bee propolis is a promising source for nutraceutical and cosmeceutical applications owing to its strong antioxidant and antidiabetic properties. The unique profile of A-ring C-methylated flavonoids potentially provides valuable insights into its botanical origin.

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.

Sea buckthorn extract mitigates chronic obstructive pulmonary disease by suppression of ferroptosis via scavenging ROS and blocking p53/MAPK pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Sea buckthorn (Hippophae rhamnoides), a traditional Tibetan medicinal herb, exhibits protective effects against cardiovascular and respiratory diseases. Although Sea buckthorn extract (SBE) has been confirmed to alleviate airway inflammation in mice, its therapeutic effect and underlying mechanism on chronic obstructive pulmonary disease (COPD) requires further clarification.

AIM OF THE STUDY

To elucidate the alleviative effect and molecular mechanism of SBE on lipopolysaccharides (LPS)/porcine pancreatic elastase (PPE)-induced COPD by blocking ferroptosis.

METHODS

The anti-ferroptotic effects of SBE were evaluated in human BEAS-2B bronchial epithelial cells using CCK8, RT-qPCR, western blotting, and transmission electron microscopy. Transwell was employed to detect chemotaxis of neutrophils. COPD model was induced by intranasally administration of LPS/PPE in mice and measured by alterations of histopathology, inflammation, and ferroptosis. RNA-sequencing, western blotting, antioxidant examination, flow cytometry, DARTS, CETSA, and molecular docking were then used to investigate its anti-ferroptotic mechanisms.

RESULTS

In vitro, SBE not only suppressed erastin- or RSL3-induced ferroptosis by suppressing lipid peroxides (LPOs) production and glutathione (GSH) depletion, but also suppressed ferroptosis-induced chemotactic migration of neutrophils via reducing mRNA expression of chemokines. In vivo, SBE ameliorated LPS/PPE-induced COPD phenotypes, and inhibited the generation of LPOs, cytokines, and chemokines. RNA-sequencing showed that p53 pathway and mitogen-activated protein kinases (MAPK) pathway were implicated in SBE-mediated anti-ferroptotic action. SBE repressed erastin- or LPS/PPE-induced overactivation of p53 and MAPK pathway, thereby decreasing expression of diamine acetyltransferase 1 (SAT1) and arachidonate 15-lipoxygenase (ALOX15), and increasing expression of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11). Mechanistically, erastin-induced elevation of reactive oxygen species (ROS) was reduced by SBE through directly scavenging free radicals, thereby contributing to its inhibition of p53 and MAPK pathways. CETSA, DARTS, and molecular docking further showed that ROS-generating enzyme nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) may be the target of SBE. Overexpression of NOX4 partially impaired the anti-ferroptotic activity of SBE.

CONCLUSION

Our results demonstrated that SBE mitigated COPD by suppressing p53 and MAPK pro-ferroptosis pathways via directly scavenging ROS and blocking NOX4. These findings also supported the clinical application of Sea buckthorn in COPD therapy.

Nigella sativa: A Comprehensive Review of Its Therapeutic Potential, Pharmacological Properties, and Clinical Applications

Nigella sativa (NS) is an annual herb belonging to the Ranunculaceae family, also known as black cumin or black seed. This plant has been used since ancient times due to its therapeutic properties and has proven effective in gastrointestinal, respiratory, cardiovascular, infectious, and inflammatory conditions. In this review, the aim is to highlight the therapeutic effects of the plant known in Arab countries as "the plant that cures any disease", which are provided by the phytochemical compounds in its composition, such as thymoquinone, p-cymene, α-thujene, longifolene, β-pinene, α-pinene, and carvacrol. These compounds confer an antioxidant effect to the seeds, leading to a significant decrease in ROS and a potent anti-inflammatory effect. Also, in this review, the aim is to highlight that NS seeds may have a synergistic effect with other drugs, such as chemotherapeutic agents or antibiotics, which may lead to a reduction in the therapeutic dose, may have an improved effect, and could lead to overcoming obstacles such as drug resistance. The studies provided in this review showed that NS has the potential to be a therapeutic agent both as a monotherapy and as an adjuvant. Although there are studies demonstrating the therapeutic properties of NS, there is a need for much more extensive research and more clinical trials with clearly established objectives so that the mechanism of action of the active substances in NS is much better understood. With the data provided so far, NS can be used in food and drug production in small quantities and can be administered for short periods. Further investigations may lead to an understanding of the therapeutic profile and the most effective mode of administration, as well as a clearer perspective on the toxicological profile of NS.

Existing Forms of Notoginsenoside R1 in Rats and Their Potential Bioactivities

Notoginsenoside R1 (NG-R1) is a primary active constituent in Panax notoginseng, a medicinal and edible plant. It is a saponin with protopanaxatriol (PPT) as its aglycone. UHPLC-ESI-Q-TOF-MS/MS was used to clarify the existing forms of NG-R1 and their distributions in rats. The nomenclature of the ESI MS fragmentation pathway and ions of PPT was proposed for the first time. Totally, 105 metabolites with 89 new metabolites were identified. In terms of their LC-MS data, 7 were accurately identified by comparison with reference compounds, and 41 were clearly identified. Polyhydroxylation, pentosylation, acetylation, glucuronidation, and amino acid conjugation are new metabolic reactions of NG-R1. In total, 69, 48, 47, 43, 24, 15, and 7 metabolites were detected in the large intestine, stomach, small intestine, liver, lungs, kidneys, and heart, respectively. Then, 48 metabolites were predicted to be effective by PharmMapper, and their mechanisms of action on three diseases were predicted by network pharmacology. Finally, the antitumor effects on cell proliferation and the anti-inflammatory effects of the eight compounds were verified by cellular experiments. These results help further elucidate the in vivo existing forms of dammarane-type triterpenoids and form the basis for discovering their effective forms in the future.

Anti-inflammatory effect of Anadenanthera colubrina var. cebil (Griseb.) Altschul in experimental elastase-induced pulmonary emphysema in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants have shown promise in the search for new treatments of pulmonary emphysema. Anadenanthera colubrina, a species native to the Caatinga biome in northeastern Brazil, is widely recognized and traditionally employed in the treatment of pulmonary diseases. Many studies corroborate popular knowledge about the medicinal applications of A. colubrina, which has demonstrated a remarkable variety of pharmacological properties, however, its anti-inflammatory and antioxidant properties are highlighted.

AIM OF THE STUDY

The objective of this study was to investigate the anti-inflammatory potential of the crude hydroethanolic extract of A. colubrina var. cebil (Griseb.) Altschul on pulmonary emphysema in rats as well as to determine its potential genotoxic and cytotoxic effects using the micronucleus assay.

MATERIALS AND METHODS

The stem bark of the plant was collected in Pimenteiras-PI and sample was extracted by maceration using 70% ethanol. A portion of the extract underwent phytochemical analyses using TLC and HPLC. In this study, 8-week-old, male Wistar rats weighing approximately ±200 g was utilized following approval by local ethics committee for animal experimentation (No. 718/2022). Pulmonary emphysema was induced through orotracheal instillation of elastase, and treatment with A. colubrina extract or dexamethasone (positive control) concomitantly during induction. Twenty-eight days after the initiation of the protocol, plasma was used for cytokine measurement. Bronchoalveolar lavage (BAL) was used for leukocyte count. After euthanasia, lung samples were processed for histological analysis and quantification of oxidative stress markers. The micronucleus test was performed by evaluating the number of polychromatic erythrocytes (PCE) with micronuclei (MNPCE) to verify potential genotoxic effects of A. colubrina. A differential count of PCE and normochromatic erythrocytes (NCE) was performed to verify the potential cytotoxicity of the extract. Parametric data were subjected to normality analysis and subsequently to analysis of variance and Tukey or Dunnett post-test, non-parametric data were treated using the Kruskal-Wallis test with Dunn's post-test for unpaired samples. P value < 0.05 were considered significant.

RESULTS

The A. colubrina extract did not show a significant increase in the number of MNPCE (p > 0.05), demonstrating low genotoxicity. No changes were observed in the PCE/NCE ratio of treated animals, compared with the vehicle, suggesting low cytotoxic potential of the extract. A significant reduction (p < 0.05) in neutrophilic inflammation was observed in the lungs of rats treated with the extract, evidenced by presence of these cells in both the tissue and BAL. The extract also demonstrated pulmonary antioxidant activity, with a significant decrease (p < 0.05) in myeloperoxidase, malondialdehyde, and nitrite levels. TNFα, IL-1β, and IL-6 levels, as well as alveolar damage, were significantly reduced in animals treated with A. colubrina extract. Phytochemical analyses identified the presence of phenolic compounds and hydrolysable tannins in the A. colubrina extract.

CONCLUSIONS

The findings of this study highlights the safety of the hydroethanolic extract of Anadenanthera colubrina, and demonstrates its potential as a therapeutic approach in the treatment of emphysema. The observed properties of this medicinal plant provide an optimistic outlook in the development of therapies for the treatment of pulmonary emphysema.

Phytochemical Characterization of Bilberries and Their Potential as a Functional Ingredient to Mitigate Ochratoxin A Toxicity in Cereal-Based Products

Mycotoxin contamination of cereals and cereal-based products is a serious problem for food safety. Antioxidant-rich ingredients such as bilberries (Vaccinium myrtillus L., VM) may mitigate their harmful effects. Firstly, total phenolic content, antioxidant activity, and analytical phytochemical composition (hydroxycinnamic and hydroxybenzoic acids, flavanols, flavonols, and anthocyanins) were assessed in lyophilized wild bilberries from Romania. Secondly, this study evaluated bilberries' effects on reducing ochratoxin A (OTA) bioaccessibility and cytotoxicity. An in vitro digestion model was developed and applied to four different types of bread: Control, VM (2%), OTA (15.89 ± 0.13 mg/kg), and OTA (16.79 ± 0.55 mg/kg)-VM (2%). The results indicated that VM decreased OTA bioaccessibility by 15% at the intestinal level. OTA-VM digests showed improved Caco-2 cell viability in comparison to OTA digests across different exposure times. Regarding the alterations in Jurkat cell line cell cycle phases and apoptosis/necrosis, significant increases in cell death were observed using OTA digests (11%), while VM addition demonstrated a protective effect (1%). Reactive oxygen species (ROS) analysis confirmed these findings, with OTA-VM digests showing significantly lower ROS levels compared to OTA digests, resulting in a 3.7-fold decrease. Thus, bilberries exhibit high potential as a functional ingredient, demonstrating protection in OTA mitigation effects.

Chemical profiling and mechanisms of Agarikon pill in a rat model of cigarette smoke-induced chronic obstructive pulmonary disease

Background and aim

Agarikon pill (AGKP), a traditional Chinese herbal formula, and has been used for chronic obstructive pulmonary disease (COPD) treatment clinically. However, the active components and exact pharmacological mechanisms are still unclear. We aimed to investigate the therapeutic effects and mechanisms of AGKP on COPD and identify the chemical constituents and active compounds.

Experimental procedure

The chemical components of AGKP were identified by ultrahigh-performance liquid chromatography coupled with quadrupole/orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap-HRMS). Network pharmacology analysis was performed to uncover the potential mechanism of AGKP. The efficiencies and mechanisms of AGKP were further confirmed in COPD animal models.

Results and conclusion

Ninety compounds from AGKP, such as flavonoids, triterpenoids, saponins, anthracenes, derivatives, phenyl propionic acid, and other organic acids, were identified in our study. AGKP improved lung function and pathological changes in COPD model rats. Additionally, inflammatory cell infiltration and proinflammatory cytokine levels were markedly reduced in COPD rats administered AGKP. Network pharmacology analysis showed that the inflammatory response is the crucial mechanism by which AGKP exerts therapeutic effects on COPD rats. WB and PCR data indicated that AGKP attenuated the inflammatory response in COPD model rats. AGKP reduces the pulmonary inflammatory response through the PI3K/AKT and MAPK TLR/NF-κB signaling pathways and exerts therapeutic effects via inhibition of inflammation and mucus hypersecretion on COPD model rats.