Potential effects of medicinal plants and secondary metabolites on acute lung injury

Exosomes derived from induced cardiopulmonary progenitor cells alleviate acute lung injury in mice

Cardiopulmonary progenitor cells (CPPs) constitute a minor subpopulation of cells that are commonly associated with heart and lung morphogenesis during embryonic development but completely subside after birth. This fact offers the possibility for the treatment of pulmonary heart disease (PHD), in which the lung and heart are both damaged. A reliable source of CPPs is urgently needed. In this study, we reprogrammed human cardiac fibroblasts (HCFs) into CPP-like cells (or induced CPPs, iCPPs) and evaluated the therapeutic potential of iCPP-derived exosomes for acute lung injury (ALI). iCPPs were created in passage 3 primary HCFs by overexpressing GLI1, WNT2, ISL1 and TBX5 (GWIT). Exosomes were isolated from the culture medium of passage 6-8 GWIT-iCPPs. A mouse ALI model was established by intratracheal instillation of LPS. Four hours after LPS instillation, ALI mice were treated with GWIT-iCPP-derived exosomes (5 × 109, 5 × 1010 particles/mL) via intratracheal instillation. We showed that GWIT-iCPPs could differentiate into cell lineages, such as cardiomyocyte-like cells, endothelial cells, smooth muscle cells and alveolar epithelial cells, in vitro. Transcription analysis revealed that GWIT-iCPPs have potential for heart and lung development. Intratracheal instillation of iCPP-derived exosomes dose-dependently alleviated LPS-induced ALI in mice by attenuating lung inflammation, promoting endothelial function and restoring capillary endothelial cells and the epithelial cells barrier. This study provides a potential new method for the prevention and treatment of cardiopulmonary injury, especially lung injury, and provides a new cell model for drug screening.

LC-QToF chemical profiling of Euphorbia grantii Oliv. and its potential to inhibit LPS-induced lung inflammation in rats via the NF-κB, CY450P2E1, and P38 MAPK14 pathways

Acute lung injury (ALI) is a life-threatening syndrome that causes high morbidity and mortality worldwide. The aerial parts of Euphorbia grantii Oliv. were extracted with methanol to give a total methanolic extract (TME), which was further fractionated into dichloromethane (DCMF) and the remaining mother liquor (MLF) fractions. Biological guided anti-inflammatory assays in vitro revealed that the DCMF showed the highest activity (IC50 6.9 ± 0.2 μg/mL and 0.29 ± 0.01 μg/mL) compared to. celecoxib (IC50 of 88.0 ± 1 μg/mL and 0.30 ± 0.01 μg/mL) on COX-1 and COX-2, respectively. Additionally, anti-LOX activity was IC50 = 24.0 ± 2.5 μg/mL vs. zileuton with IC50 of 40.0 ± 0.5 μg/mL. LC-DAD-QToF analysis of TME and the active DCMF resulted in the tentative identification and characterization of 56 phytochemical compounds, where the diterpenes were the dominated metabolites. An LPS-induced inflammatory model of ALI (10 mg/kg i.p) was used to assess the anti-inflammatory potential of DCMF in vivo at dose of 200 mg/kg and 300 mg/kg compared to dexamethasone (5 mg/kg i.p). Our treatments significantly reduced the pro-inflammatory cytokines (TNF-α, IL-1, IL-6, and MPO), increased the activity of antioxidant enzymes (SOD, CAT, and GSH), decreased the activity of oxidative stress enzyme (MDA), and reduced the expression of inflammatory genes (p38.MAPK14 and CY450P2E1). The western blotting of NF-κB p65 in lung tissues was inhibited after orally administration of the DCMF. Histopathological study of the lung tissues, scoring, and immunohistochemistry of transforming growth factor-beta 1 (TGF-β1) were also assessed. In both dose regimens, DCMF of E. grantii prevented further lung damage and reduced the side effects of LPS on acute lung tissue injury.

Solanum nigrum L. in COVID-19 and post-COVID complications: a propitious candidate

COVID-19 is caused by severe acute respiratory syndrome coronavirus-2, SARS-CoV-2. COVID-19 has changed the world scenario and caused mortality around the globe. Patients who recovered from COVID-19 have shown neurological, psychological, renal, cardiovascular, pulmonary, and hematological complications. In some patients, complications lasted more than 6 months. However, significantly less attention has been given to post-COVID complications. Currently available drugs are used to tackle the complications, but new interventions must address the problem. Phytochemicals from natural sources have been evaluated in recent times to cure or alleviate COVID-19 symptoms. An edible plant, Solanum nigrum, could be therapeutic in treating COVID-19 as the AYUSH ministry of India prescribes it during the pandemic. S. nigrum demonstrates anti-inflammatory, immunomodulatory, and antiviral action to treat the SARS-CoV-2 infection and its post-complications. Different parts of the plant represent a reduction in proinflammatory cytokines and prevent multi-organ failure by protecting various organs (liver, kidney, heart, neuro, and lung). The review proposes the possible role of the plant S. nigrum in managing the symptoms of COVID-19 and its post-COVID complications based on in silico docking and pharmacological studies. Further systematic and experimental studies are required to validate our hypothesis.

COVID-19 associated thyroid dysfunction and other comorbidities and its management using phytochemical-based therapeutics: a natural way

The present severe acute respiratory syndrome-2 (SARS-CoV-2) mediated Coronavirus pandemic (COVID-19) and post-COVID-19 complications affect human life drastically. Patients who have been cured of COVID-19 infection are now experiencing post-COVID-19 associated comorbidities, which have increased mortality rates. The SARS-CoV-2 infection distresses the lungs, kidneys, gastrointestinal tract, and various endocrine glands, including the thyroid. The emergence of variants which includes Omicron (B.1.1.529) and its lineages threaten the world severely. Among different therapeutic approaches, phytochemical-based therapeutics are not only cost-effective but also have lesser side effects. Recently a plethora of studies have shown the therapeutic efficacy of various phytochemicals for the treatment of COVID-19. Besides this, various phytochemicals have been found efficacious in treating several inflammatory diseases, including thyroid-related anomalies. The method of the phytochemical formulation is quick and facile and the raw materials for such herbal preparations are approved worldwide for human use against certain disease conditions. Owing to the advantages of phytochemicals, this review primarily discusses the COVID-19-related thyroid dysfunction and the role of key phytochemicals to deal with thyroid anomaly and post-COVID-19 complications. Further, this review shed light on the mechanism via which COVID-19 and its related complication affect organ function of the body, along with the mechanistic insight into the way by which phytochemicals could help to cure post-COVID-19 complications in thyroid patients. Considering the advantages offered by phytochemicals as a safer and cost-effective medication they can be potentially used to combat COVID-19-associated comorbidities.

Efficacy of a Persian herbal medicine compound on coronavirus disease 2019 (COVID-19): a randomized clinical trial

Background

The global attention to the capacities of traditional medicine for alleviating the clinical manifestations of COVID-19 has been growing. The present trial aimed to evaluate the efficacy and safety of a Persian herbal medicine formula among patients with COVID-19.

Methods

The present trial was conducted in Afzalipour hospital, Kerman, Iran, from June to September 2020. Hospitalized COVID-19 patients were randomly divided into intervention (Persian herbal medicine formula + routine treatment) or control (only routine treatment) groups. The intervention group received both capsule number 1 and 2 every 8 hours for 7 days. Capsule number 1 contained extract of the Glycyrrhiza glabra, Punica granatum, and Rheum palmatum, and the second capsule was filled by Nigella sativa powder. Participants were followed up to 7 days. The primary outcome was the number of hospitalization days, while cough, fever, and respiratory rate, days on oxygen (O₂) therapy, and mortality rate were considered as the secondary outcomes.

Results

Eighty-two patients were enrolled to the study, while 79 cases completed the trial and their data were analyzed (mean age: 59.1 ± 17.1 years). Based on the results, the Persian medicine formula decreased the mean hospitalization days, so that the mean difference of length of hospitalization as primary outcome was 2.95 ± 0.43 days. A significant clinical improvement was observed regarding dyspnea, need for O₂) therapy, and respiratory rate in the intervention group. No adverse effects were reported.

Conclusion

The present study supported the use of the Persian medicine formula as an adjuvant therapy for hospitalized COVID-19 patients. Study registration: Iranian Registry of Clinical Trials (www.irct.ir): IRCT20200330046899N1.

Study registration

Iranian Registry of Clinical Trials (www.irct.ir): IRCT20200330046899N1.

Vasorelaxant Effects of the Vitex Agnus-Castus Extract

This study was undertaken to describe and characterize the relaxing effects of the medicinal plant Vitex agnus-castus (VAC) extract on isolated rabbit arterial rings. The VAC extracts (VACE) were extracted with ethanol and tested in aorta rings (3-4 mm) of rabbits suspended in an organ bath (Krebs, 37°C, 95% O₂/5% CO₂) under a resting tension of 1 g to record isometric contractions. After the stabilization period (1-2 hours), contractions were induced by the addition of phenylephrine (0.5 μM) or high KCl (80 mM) and VACE was added on the plateau of the contractions. Experiments were performed to determine the effects and to get insights into the potential mechanism involved in VACE-induced relaxations. The cumulative addition of VACE (0.15–0.75 mg/mL) relaxed, in a concentration-dependent manner, the rabbit aorta rings precontracted either with phenylephrine- or with high KCl thus suggesting calcium channel blocking activities. The VACE effect appeared to be endothelium-dependent. The preincubation with L-NAME (the inhibitor of nitric oxide synthases (NOS)), ODQ (the selective inhibitor of guanylyl cyclase), and indomethacin (the cyclooxygenase inhibitor), downregulated VACE-induced relaxation of aorta rings precontracted with phenylephrine, whereas the bradykinin (stimulator of NOS) and zaprinast (phosphodiesterase inhibitor) further upregulated relaxant effects induced by VACE. These results revealed that the aorta relaxation effect of VACE was mainly endothelium-dependent and mediated by NO/cGMP and prostaglandins synthesis. This vasodilator effect of VACE may be useful to treat cardiovascular disorders, including hypertensive diseases.

Efficacy of Persian medicine herbal formulations (capsules and decoction) compared to standard care in patients with COVID-19, a multicenter open-labeled, randomized, controlled clinical trial

Persian medicine has recommended clinical experiences and proper herbal remedies for prevention and treatment of microbial infections and respiratory diseases. An open‐label, randomized, controlled, multicenter trial was conducted at five hospitals in Tehran and Isfahan provinces of Iran on 358 hospitalized adult patients. A total of 174 patients received standard care and 184 received herbal remedies (polyherbal decoction every 8 hr and two herbal capsules every 12 hr) plus standard care for 7 days. The primary clinical endpoint was the duration of hospital stay, and secondary outcomes were clinical improvement of symptoms based on self‐assessment questionnaire. Results demonstrated that these natural decoction and capsules treatment plus routine care significantly decreased duration of hospital dyspnea (3.291 day vs. 6.468 days), accelerated clinical improvement, and decreased symptoms such as dry cough, dyspnea, muscle pain, headache, fatigue, anorexia, chills, runny nose, sputum cough, and vertigo in the treatment group compared with standard‐care group. Significant effects of these polyherbal formulations on improving the symptoms of COVID‐19 could be incredibly promising for managing this pandemic with acceptable tolerability.

The effect of ellagic acid on the repair process of periodontal defects related to experimental periodontitis in rats

Objective

This study aims to evaluate the effect of ellagic acid (EA) by measuring the levels of alveolar bone resorption and inflammatory and oxidative stress markers in the periodontal tissues and serum on the periodontal repair process related to experimental periodontitis in rats.

Methodology

Forty Wistar rats were divided into four study groups as follows: Group 1=healthy control (n=10); Group 2=EA control (15 mg/kg)(n=10); Group 3=periodontitis (n=10); Group 4=periodontitis+EA (15 mg/kg) (n=10). The periodontitis model was established by ligating bilateral mandibular first molars for 14 days. Then, rats were given normal saline or EA for another 14 days by gavage administration. Serum and gingiva myeloperoxidase (MPO) activity, 8-hydroxydeoxyguanosine(8-OHdG), and glutathione (GSH) levels were analyzed by ELISA. İmmunohistochemical analysis was used to detect Interleukin (IL)-6, IL-10, and tumor necrosis factor-alpha (TNF-α) immunoreactivities in the periodontal tissues. Alveolar bone loss (ABL) and attachment loss (AL) was evaluated by histomorphometry analysis.

Results

ABL and AL were statistically higher in group 3 than in groups 1, 2 and 4 and in group 4 than in groups 1 and 2 (p<0.05). MPO activities in gingival tissue and serum were significantly increased in group 3 compared to groups 1 and 2 (p<0.05). Significantly higher serum GSH levels, lower gingiva, and serum 8-OHdG levels, and MPO activity were observed in group 4 compared to group 3 (p<0.05). Rats with periodontitis (group 3) expressed significantly higher immunoreactivities of IL-6 and TNF-α and lower IL-10 immunoreactivity compared to those other groups (p<0.05). IL-6 and TNF-α immunoreactivities significantly decreased and IL-10 immunoreactivity increased in group 4 after the use of EA compared to group 3 (p<0.001).

Conclusions

Our findings showed that EA provides significant improvements on gingival oxidative stress and inflammatory markers and alveolar bone resorption in the repair process associated with experimental periodontitis. Therefore, EA may have a therapeutic potential on periodontitis.

Long non-coding RNA OIP5-AS1 aggravates acute lung injury by promoting inflammation and cell apoptosis via regulating the miR-26a-5p/TLR4 axis

Background

Acute lung injury (ALI) is a pulmonary disorder that leads to acute respiration failure and thereby results in a high mortality worldwide. Increasing studies have indicated that toll-like receptor 4 (TLR4) is a promoter in ALI, and we aimed to explore the underlying upstream mechanism of TLR4 in ALI.

Methods

We used lipopolysaccharide (LPS) to induce an acute inflammatory response in vitro model and a murine mouse model. A wide range of experiments including reverse transcription quantitative polymerase chain reaction, western blot, enzyme linked immunosorbent assay, flow cytometry, hematoxylin–eosin staining, RNA immunoprecipitation, luciferase activity and caspase-3 activity detection assays were conducted to figure out the expression status, specific role and potential upstream mechanism of TLR4 in ALI.

Result

TLR4 expression was upregulated in ALI mice and LPS-treated primary bronchial/tracheal epithelial cells. Moreover, miR-26a-5p was confirmed to target TLR4 according to results of luciferase reporter assay. In addition, miR-26a-5p overexpression decreased the contents of proinflammatory factors and inhibited cell apoptosis, while upregulation of TLR4 reversed these effects of miR-26a-5p mimics, implying that miR-26a-5p alleviated ALI by regulating TLR4. Afterwards, OPA interacting protein 5 antisense RNA 1 (OIP5-AS1) was identified to bind with miR-26a-5p. Functionally, OIP5-AS1 upregulation promoted the inflammation and miR-26a-5p overexpression counteracted the influence of OIP5-AS1 upregulation on cell inflammatory response and apoptosis.

Conclusion

OIP5-AS1 promotes ALI by regulating the miR-26a-5p/TLR4 axis in ALI mice and LPS-treated cells, which indicates a promising insight into diagnostics and therapeutics in ALI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01589-1.

Phenylethanoid Glycosides From Callicarpa kwangtungensis Chun Attenuate TNF-α-Induced Cell Damage by Inhibiting NF-κB Pathway and Enhancing Nrf2 Pathway in A549 Cells

Background: Acute lung injury (ALI) is a complicated and severe lung disease, which is often characterized by acute inflammation. Poliumoside (POL), acteoside (ACT) and forsythiaside B (FTB) are phenylethanoid glycosides (PGs) with strong antioxidant, anti-inflammatory, and anti-apoptotic properties, which are extracted from Callicarpa kwangtungensis Chun (CK). The aim of this study was to investigate the protective effects of POL, ACT, and FTB against TNF-α-induced damage using an ALI cell model and explore their potential mechanisms.

Methods and Results: MTT method was used to measure cell viability. Flow cytometry was used for detecting the apoptosis rate. Reactive oxygen species (ROS) activity was determined using fluorescence microscope. The expression of mRNA in apoptosis-related genes (Caspase 3, Caspase 8, and Caspase 9) were tested by qPCR. The effects of POL, ACT, FTB on the activities of nuclear factor erythroid-2 related factor 2 (Nrf2), nuclear factor kappa-B (NF-κB) and the expression of their downstream genes were assessed by western blotting and RT-PCR in A549 cells. In the current study, POL, ACT, and FTB dose-dependently attenuated TNF-α-induced IL-1β, IL-6 and IL-8 production, cell apoptosis, the expression of apoptosis-related genes (Caspase 3, Caspase 8, and Caspase 9) and ROS activity. POL, ACT, and FTB not only increased in the mRNA levels of antioxidative enzymes NADPH quinone oxidoreductase (NQO1), glutamate cysteine ligase catalytic subunit (GCLC), heme oxygenase (HO-1), but also decreased the mRNA levels of IL-1β, IL-6 and IL-8. Furthermore, they upregulated the expression of Keap1 and enhanced the activation of Nrf2, while decreased the expression of phosphor-IκBα (p-IκBα) and nuclear p65. In addition, no significant changes were observed in anti-inflammatory and antioxidant effects of POL, ACT, FTB following Nrf2 and NF-κB p65 knockdown.

Conclusion: Our study revealed that POL, ACT, and FTB alleviated oxidative damage and lung inflammation of TNF-α-induced ALI cell model through regulating the Nrf2 and NF-κB pathways.

Long non-coding RNA NEAT1 promotes lipopolysaccharide-induced acute lung injury by regulating miR-424-5p/MAPK14 axis

BACKGROUND

Many long non-coding RNAs (lncRNAs) have been suggested to play critical roles in acute lung injury (ALI) pathogenesis, including lncRNA nuclear enriched abundant transcript 1 (NEAT1).

OBJECTIVE

We aimed to further elucidate the functions and molecular mechanism of NEAT1 in ALI.

METHODS

Human pulmonary alveolar epithelial cells (HPAEpiCs) stimulated by lipopolysaccharide (LPS) were served as a cellular model of ALI. Cell viability and cell apoptosis were determined by cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. The expression of NEAT1, microRNA-424-5p (miR-424-5p), and mitogen-activated protein kinase 14 (MAPK14) was measured by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot analysis. Caspase activity was determined by caspase activity kit. The inflammatory responses were evaluated using enzyme-linked immunosorbent assay (ELISA). The oxidative stress factors were analyzed by corresponding kits.

RESULTS

NEAT1 was upregulated in LPS-stimulated HPAEpiCs. NEAT1 knockdown weakened LPS-induced injury by inhibiting apoptosis, inflammation and oxidative stress in HPAEpiCs. Moreover, miR-424-5p was a direct target of NEAT1, and its knockdown reversed the effects caused by NEAT1 knockdown in LPS-induced HPAEpiCs. Furthermore, MAPK14 was a downstream target of miR-424-5p, and its overexpression attenuated the effects of miR-424-5p on reduction of LPS-induced injury in HPAEpiCs. Besides, NEAT1 acted as a sponge of miR-424-5p to regulate MAPK14 expression.

CONCLUSION

NEAT1 knockdown alleviated LPS-induced injury of HPAEpiCs by regulating miR-424-5p/MAPK14 axis, which provided a potential therapeutic target for the treatment of ALI.

Optimization of Tabersonine Methoxylation to Increase Vindoline Precursor Synthesis in Yeast Cell Factories

Plant specialized metabolites are widely used in the pharmaceutical industry, including the monoterpene indole alkaloids (MIAs) vinblastine and vincristine, which both display anticancer activity. Both compounds can be obtained through the chemical condensation of their precursors vindoline and catharanthine extracted from leaves of the Madagascar periwinkle. However, the extensive use of these molecules in chemotherapy increases precursor demand and results in recurrent shortages, explaining why the development of alternative production approaches, such microbial cell factories, is mandatory. In this context, the precursor-directed biosynthesis of vindoline from tabersonine in yeast-expressing heterologous biosynthetic genes is of particular interest but has not reached high production scales to date. To circumvent production bottlenecks, the metabolic flux was channeled towards the MIA of interest by modulating the copy number of the first two genes of the vindoline biosynthetic pathway, namely tabersonine 16-hydroxylase and tabersonine-16-O-methyltransferase. Increasing gene copies resulted in an optimized methoxylation of tabersonine and overcame the competition for tabersonine access with the third enzyme of the pathway, tabersonine 3-oxygenase, which exhibits a high substrate promiscuity. Through this approach, we successfully created a yeast strain that produces the fourth biosynthetic intermediate of vindoline without accumulation of other intermediates or undesired side-products. This optimization will probably pave the way towards the future development of yeast cell factories to produce vindoline at an industrial scale.

Nrf2-interacting nutrients and COVID-19: time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPARγ:Peroxisome proliferator-activated receptor, NFκB: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2α:Elongation initiation factor 2α). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT₁R axis (AT₁R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity.

Phytochemicals: Potential Therapeutic Interventions Against Coronavirus-Associated Lung Injury

Since the outbreak of coronavirus disease 2019 (COVID-19) in December 2019, millions of people have been infected and died worldwide. However, no drug has been approved for the treatment of this disease and its complications, which urges the need for finding novel therapeutic agents to combat. Among the complications due to COVID-19, lung injury has attained special attention. Besides, phytochemicals have shown prominent anti-inflammatory effects and thus possess significant effects in reducing lung injury caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Also, the prevailing evidence reveales the antiviral effects of those phytochemicals, including anti-SARS-CoV activity, which could pave the road in providing suitable lead compounds in the treatment of COVID-19. In the present study, candidate phytochemicals and related mechanisms of action have been shown in the treatment/protection of lung injuries induced by various methods. In terms of pharmacological mechanism, phytochemicals have shown potential inhibitory effects on inflammatory and oxidative pathways/mediators, involved in the pathogenesis of lung injury during COVID-19 infection. Also, a brief overview of phytochemicals with anti-SARS-CoV-2 compounds has been presented.

Traditional medicinal plants against replication, maturation and transmission targets of SARS-CoV-2: computational investigation

COVID-19 is an infectious pandemic caused by the SARS-CoV-2 virus. The critical components of SARS-CoV-2 are the spike protein (S-protein) and the main protease (M^pro). M^pro is required for the maturation of the various polyproteins involved in replication and transcription. S-protein helps the SARS-CoV-2 to enter the host cells through the angiotensin-converting enzyme 2 (ACE2). Since ACE2 is required for the binding of SARS-CoV-2 on the host cells, ACE2 inhibitors and blockers have got wider attention, in addition to S-protein and M^pro modulators as potential therapeutics for COVID-19. So far, no specific drugs have shown promising therapeutic potential against COVID-19. The current study was undertaken to evaluate the therapeutic potential of traditional medicinal plants against COVID-19. The bioactives from the medicinal plants, along with standard drugs, were screened for their binding against S-protein, M^pro and ACE2 targets using molecular docking followed by molecular dynamics. Based on the higher binding affinity compared with standard drugs, bioactives were selected and further analyzed for their pharmacological properties such as drug-likeness, ADME/T-test, biological activities using in silico tools. The binding energies of several bioactives analyzed with target proteins were relatively comparable and even better than the standard drugs. Based on Lipinski factors and lower binding energies, seven bioactives were further analyzed for their pharmacological and biological characteristics. The selected bioactives were found to have lower toxicity with a higher GI absorption rate and potent anti-inflammatory and anti-viral activities against targets of COVID-19. Therefore, the bioactives from these medicinal plants can be further developed as phytopharmaceuticals for the effective treatment of COVID-19.

Mesenchymal stem cells reverse EMT process through blocking the activation of NF-κB and Hedgehog pathways in LPS-induced acute lung injury

Acute lung injury (ALI) is a pulmonary disorder, which can result in fibrosis of the lung tissues. Recently, mesenchymal stem cell (MSC) has become a novel therapeutic method for ALI. However, the potential mechanism by which MSC regulates the progression of ALI remains blurry. The present study focused on investigating the mechanism underneath MSC-reversed lung injury and fibrosis. At first, we determined that coculture with MSC led to the inactivation of NF-κB signaling and therefore suppressed hedgehog pathway in LPS-treated MLE-12 cells. Besides, we confirmed that MSC-exosomes were responsible for the inhibition of EMT process in LPS-treated MLE-12 cells through transmitting miRNAs. Mechanism investigation revealed that MSC-exosome transmitted miR-182-5p and miR-23a-3p into LPS-treated MLE-12 cells to, respectively, target Ikbkb and Usp5. Of note, Usp5 interacted with IKKβ to hamper IKKβ ubiquitination. Moreover, co-inhibition of miR-182-5p and miR-23a-3p offset the suppression of MSC on EMT process in LPS-treated MLE-12 cells as well as in LPS-injured lungs of mice. Besides, the retarding effect of MSC on p65 nuclear translocation was also counteracted after co-inhibiting miR-182-5p and miR-23a-3p, both in vitro and in vivo. In summary, MSC-exosome transmitted miR-23a-3p and miR-182-5p reversed the progression of LPS-induced lung injury and fibrosis through inhibiting NF-κB and hedgehog pathways via silencing Ikbkb and destabilizing IKKβ.

Insight into the Mechanisms Underlying the Tracheorelaxant Properties of the Sideritis raeseri Extract

Sideritis raeseri Boiss. and Heldr. (Lamiaceae), known as “mountain tea,” is a native plant from the Mediterranean region, which is widely used in traditional medicine. This study evaluates the effects of the ethanol extract of Sideritis raeseri (SR) on airway smooth muscle activity and identifies the underlying mechanism. The S. raeseri extract (SRE) was extracted from air-dried parts of the shoot system of SR. The SRE (0.3–2 mg/mL) was tested in isolated rabbit tracheal rings, suspended in the organ bath, filled with Krebs solution, and bubbled with the carbogen mixture (95% O2/5% CO2) under a resting tension of 1 g in 37°C. In in vitro experiments, the SRE relaxed against acetylcholine-induced constriction in tracheal rings. Furthermore, SRE inhibited Ca2+-induced contractions in carbachol (CCh, 1 μM) as well as in the K+-depolarized trachea (80 mM). Our findings showed the NO/cGMP involvement in tracheorelaxant effects of SR. To this end, the effect of the SRE was potentiated by bradykinin (nitric oxide (NO) synthase activator, 100 nM), whereas it was inhibited by ODQ (inhibitor of NO-sensitive guanylyl cyclase, 10 μM) and L-NAME (NO synthase inhibitor, 100 μM), as well as indomethacin (cyclooxygenase inhibitor, 10 μM). These data suggest that the tracheorelaxant effect of the SRE is mediated at least partly by NO/cyclic guanosine monophosphate and cyclooxygenase-1-prostaglandin E2-dependent signaling. These findings indicate that the SRE may be used in various respiratory disorders.

Effect of bovine lactoferrin as a novel therapeutic agent in a rat model of sepsis-induced acute lung injury

Sepsis is a serious clinical condition resulting from severe infection. High rates of mortality and tissue damage have been reported in intensive care unit (ICU) patients with sepsis. Bovine lactoferrin (BLF) is a well-known 80-kDa glycoprotein in the transferrin family that inhibits sepsis in low-birth-weight neonates. The present study investigated the protective effects of BLF in a rat model of sepsis-induced acute lung injury (ALI). The wet/dry ratio, lipid peroxidation, antioxidant markers, total protein, total cell count, inflammatory markers and myeloperoxidase (MPO) levels were assessed. Histopathological analysis was also carried out. BLF treatment reduced the wet/dry ratio of lung tissue by 30.7% and 61.3%, and lipid peroxidation by 22.3% and 67%, at concentrations of 100 and 200 mg/kg, respectively. Superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (Gpx) and catalase were increased by more than 50% under treatment with 200 mg/kg BLF. Inflammatory markers, neutrophils, lymphocytes and total cell count were reduced by more than 50% under treatment with 200 mg/kg BLF. BLF treatment significantly reduced MPO activity, by 28.2% and 74.3%, at concentrations of 100 and 200 mg/kg, respectively. Neutrophilic infiltration and edema were observed in control rats. However, BLF treatment restored intestinal microvilli to the normal range and reduced inflammatory cell invasion. Collectively, these results suggest that BLF is an effective therapeutic agent against sepsis-induced ALI.

Neutrophil Immunomodulatory Activity of Natural Organosulfur Compounds

Organosulfur compounds are bioactive components of garlic essential oil (EO), mustard oil, Ferula EOs, asafoetida, and other plant and food extracts. Traditionally, garlic (Allium sativum) is used to boost the immune system; however, the mechanisms involved in the putative immunomodulatory effects of garlic are unknown. We investigated the effects of garlic EO and 22 organosulfur compounds on human neutrophil responses. Garlic EO, allyl propyl disulfide, dipropyl disulfide, diallyl disulfide, and allyl isothiocyanate (AITC) directly activated Ca²⁺ flux in neutrophils, with the most potent being AITC. Although 1,3-dithiane did not activate neutrophil Ca²⁺ flux, this minor constituent of garlic EO stimulated neutrophil reactive oxygen species (ROS) production. In contrast, a close analog (1,4-dithiane) was unable to activate neutrophil ROS production. Although 1,3-dithiane-1-oxide also stimulated neutrophil ROS production, only traces of this oxidation product were generated after a 5 h treatment of HL60 cells with 1,3-dithiane. Evaluation of several phosphatidylinositol-3 kinase (PI3K) inhibitors with different subtype specificities (A-66, TGX 221, AS605240, and PI 3065) showed that the PI3K p110δ inhibitor PI 3065 was the most potent inhibitor of 1,3-dithiane-induced neutrophil ROS production. Furthermore, 1,3-dithiane enhanced the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), glycogen synthase kinase 3 α/β (GSK-3α/β), and cAMP response element binding (CREB) protein in differentiated neutrophil-like HL60 cells. Density functional theory (DFT) calculations confirmed the reactivity of 1,3-dithiane vs. 1,4-dithiane, based on the frontier molecular orbital analysis. Our results demonstrate that certain organosulfur compounds can activate neutrophil functional activity and may serve as biological response modifiers by augmenting phagocyte functions.

Long non-coding RNA CASC2 improved acute lung injury by regulating miR-144-3p/AQP1 axis to reduce lung epithelial cell apoptosis

Background and objective

Apoptosis of lung epithelial cell is implicated in the pathogenesis of acute lung injury (ALI). To study the protective effect and mechanism of cancer susceptibility candidate 2 (CASC2) on reducing lung epithelial cell apoptosis after LPS inducing acute lung injury in mice.

Methods and results

The ALI mice model was performed by intratracheally instilling with lipopolysaccharide (LPS). The CASC2 expression detected by quantitative real-time polymerase chain reaction was significantly decreased in LPS-induced A549 cell and ALI mice model. LPS induced A549 cell apoptosis, while transfection with pcDNA-CASC2 reversed the increased cell apoptosis, suggesting overexpression of CASC2 inhibited LPS-induced A549 cell apoptosis. In addition, we found that miR-144-3p expression were opposite to CASC2, while Aquaporin-1 (AQP1) expression was opposite to miR-144-3p in LPS-induced A549 cell and ALI mice model. The RNA immunoprecipitation and RNA pull-down assay demonstrated that CASC2 could function as a miR-144-3p decoy. The luciferase reporter assay revealed that AQP1 was a target of miR-144-3p in A549 cell. And then, further in vitro studied showed that CASC2 controlled AQP1 expression by regulating miR-144-3p, and LPS induced A549 cell apoptosis by regulating CASC2/miR-144-3p/AQP1 axis. At last, after injection with lentivirus-expressing CASC2 or control lentivirus, the mice were intratracheally instilled with LPS. Comparing to the mice injected with pcDNA, the mice injected with pcDNA-CASC2 had a significantly reduced lung wet–dry weight ratio.

Conclusions

Long non-coding RNA CASC2 improved acute lung injury by regulating miR-144-3p/AQP1 axis to reduce lung epithelial cell apoptosis.

Therapeutic Potential of Medicinal Plants and Their Constituents on Lung Inflammatory Disorders

Acute bronchitis and chronic obstructive pulmonary diseases (COPD) are essentially lung inflammatory disorders. Various plant extracts and their constituents showed therapeutic effects on several animal models of lung inflammation. These include coumarins, flavonoids, phenolics, iridoids, monoterpenes, diterpenes and triterpenoids. Some of them exerted inhibitory action mainly by inhibiting the mitogen-activated protein kinase pathway and nuclear transcription factor-κB activation. Especially, many flavonoid derivatives distinctly showed effectiveness on lung inflammation. In this review, the experimental data for plant extracts and their constituents showing therapeutic effectiveness on animal models of lung inflammation are summarized.

Protective effect of bone marrow derived mesenchymal stem cells in lipopolysaccharide-induced acute lung injury mediated by claudin-4 in a rat model

Our study aims to investigate the effects of bone marrow derived mesenchymal stem cells (BM-MSCs) in lipopolysaccharide (LPS)-induced acute lung injury (ALI) as well as the underlying mechanism. In our study, Wistar rats were randomly divided into four groups: control group; ALI group; ALI+MSCs group and ALI+MSCs claudin-4 siRNA group. MRC-5 and BEAS-2B cell lines were used for in vitro assay. Flow cytometry, western blot, hematoxylin and eosin (H&E) staining, CCK-8 assay, enzyme-linked immunosorbent assay (ELISA) were involved to measure the pathological changes in lung tissues. Results showed that in vivo MSCs administration significantly attenuated pulmonary edema (wet/dry ratio), inflammation cytokines levels (TGF-α), pathological alternations and cell apoptosis which were mediated by claudin-4 in LPS-induced acute lung injury in rats. In vitro experiment showed that hypoxia could induce the expression of claudin-4 in MSCs, and MSCs treatment showed significantly enhanced cell viability (by CCK-8 assay) and reduced cell apoptosis. In conclusion, the present study demonstrated that BM-MSCs can protect against LPS-induced ALI in vivo and in vitro, at least partly mediated by claudin-4.

Antioxidant and Antihyperlipidemic Effects of Campomanesia adamantium O. Berg Root

Campomanesia adamantium O. Berg, popularly known as guavira, has been used in Brazilian traditional medicine for reduction of serum lipid. The present study was carried out to investigate the antioxidant and antihyperlipidemic effects of Campomanesia adamantium root aqueous extract (ExCA). Phenolic compounds were quantified in the ExCA and gallic and ellagic acids were identified by HPLC. ExCA showed efficiency in 2,2-diphenyl-1-picrylhydrazyl free radical scavenging, with IC₅₀ similar to butylhydroxytoluene control, and protected the erythrocytes against lipid peroxidation induced by 2,2′-azobis(2-methylpropionamidine) dihydrochloride, reducing generated malondialdehyde. Hyperlipidemic Wistar rats treated daily by gavage during eight weeks with ExCA (200 mg/kg of body weight) showed reduced serum level of total cholesterol and triglycerides, similar to normolipidemic rats and hyperlipidemic rats treated with simvastatin (30 mg/kg of body weight) and ciprofibrate (2 mg/kg of body weight). Moreover, the treatment with ExCA also decreased malondialdehyde serum level in the hyperlipidemic rats. The body weight and organ mass were unmodified by ExCA in hyperlipidemic rats, except an increase of liver mass; however, the hepatic enzymes, alanine aminotransferase and aspartate aminotransferase, were unchanged. Together, these results confirm the potential value of Campomanesia adamantium root for lowering lipid peroxidation and lipid serum level, improving risk factors for cardiometabolic diseases development.

The mechanism underlying alpinetin-mediated alleviation of pancreatitis-associated lung injury through upregulating aquaporin-1

Characterized by its acute onset, critical condition, poor prognosis, and high mortality rate, severe acute pancreatitis (SAP) can cause multiple organ failure at its early stage, particularly acute lung injury (ALI). The pathogenesis of ALI is diffuse alveolar damage, including an increase in pulmonary microvascular permeability, a decrease in compliance, and invasion of many inflammatory cells. Corticosteroids are the main treatment method for ALI; however, the associated high toxicity and side effects induce pain in patients. Recent studies show that the effective components in many traditional Chinese medicines can effectively inhibit inflammation with few side effects, which can decrease the complications caused by steroid consumption. Based on these observations, the main objective of the current study is to investigate the effect of alpinetin, which is a flavonoid extracted from Alpinia katsumadai Hayata, on treating lung injury induced by SAP and to explore the mechanism underlying the alpinetin-mediated decrease in the extent of ALI. In this study, we have shown through in vitro experiments that a therapeutic dose of alpinetin can promote human pulmonary microvascular endothelial cell proliferation. We have also shown via in vitro and in vivo experiments that alpinetin upregulates aquaporin-1 and, thereby, inhibits tumor necrosis factor-α expression as well as reduces the degree of lung injury. Overall, our study shows that alpinetin alleviates SAP-induced ALI. The likely molecular mechanism includes upregulated aquaporin expression, which inhibits tumor necrosis factor-α and, thus, alleviates SAP-induced ALI.

Identification of target proteins of mangiferin in mice with acute lung injury using functionalized magnetic microspheres based on click chemistry

Prevention of the occurrence and development of inflammation is a vital therapeutic strategy for treating acute lung injury (ALI). Increasing evidence has shown that a wealth of ingredients from natural foods and plants have potential anti-inflammatory activity. In the present study, mangiferin, a natural C-glucosyl xanthone that is primarily obtained from the peels and kernels of mango fruits and the bark of the Mangifera indica L. tree, alleviated the inflammatory responses in lipopolysaccharide (LPS)-induced ALI mice. Mangiferin-modified magnetic microspheres (MMs) were developed on the basis of click chemistry to capture the target proteins of mangiferin. Mass spectrometry and molecular docking identified 70 kDa heat-shock protein 5 (Hspa5) and tyrosine 3-monooxygenase (Ywhae) as mangiferin-binding proteins. Furthermore, an enzyme-linked immunosorbent assay (ELISA) indicated that mangiferin exerted its anti-inflammatory effect by binding Hspa5 and Ywhae to suppress downstream mitogen-activated protein kinase (MAPK) signaling pathways. Thoroughly revealing the mechanism and function of mangiferin will contribute to the development and utilization of agricultural resources from M. indica L.

Xuebijing injection improves the respiratory function in rabbits with oleic acid-induced acute lung injury by inhibiting IL-6 expression and promoting IL-10 expression at the protein and mRNA levels

Xuebijing injection is a complex herbal medicine, and clinical and experimental studies have shown that it has a significant effect on acute respiratory distress syndrome and multiple organ dysfunction syndrome. However, the majority of studies regarding Xuebijing injection have focused on serum inflammatory factors, and few studies have been carried out from the perspective of the protein and mRNA expression of inflammatory cytokines. In this study, 60 healthy rabbits of mixed gender were randomly assigned to a normal control group (CG), oleic acid group (model group; MG) and oleic acid + Xuebijing injection group (treatment group; TG). Rabbits of the CG were treated with normal saline through the ear vein, rabbits of the MG were injected with oleic acid (0.4 ml/kg) and rabbits of the TG received 0.4 ml/kg oleic acid + 10 ml/kg Xuebijing injection. Blood samples were collected from the common carotid artery of all rabbits of all groups 1 h after the ear vein was injected with the corresponding reagent, and was used to measure the arterial partial pressure of oxygen (PaO₂) and of carbon dioxide (PaCO₂). The activity of myeloperoxidase (MPO) was tested, and the protein and mRNA expression levels of interleukin (IL)-6 and IL-10 were determined. Rabbits of the MG exhibited evident respiratory dysfunction (PaO₂ and PaCO₂ were low), histopathological lung damage and overactive inflammatory responses (the expression of the proinflammatory cytokine IL-6 and the anti-inflammatory cytokine IL-10 was increased at the protein and mRNA levels). Following the administration of the Xuebijing injection, the inflammatory response of the rabbits was significantly reduced. Xuebijing injection raised PaO₂ and PaCO₂, weakened the activity of MPO in the lung tissue, downregulated the expression of the proinflammatory cytokine IL-6 and further increased the expression of the anti-inflammatory cytokine IL-10. These results demonstrated that Xuebijing injection improved the respiratory function of rabbits with acute oleic acid-induced lung injury by inhibiting IL-6 expression and promoting IL-10 expression.