Effect of a plant polyphenol-rich extract on the lung protease activities of influenza-virus-infected mice

Emerging Therapeutic Potential of Polyphenols from Geranium sanguineum L. in Viral Infections, Including SARS-CoV-2

The existing literature supports the anti-inflammatory, antioxidant, and antiviral capacities of the polyphenol extracts derived from Geranium sanguineum L. These extracts exhibit potential in hindering viral replication by inhibiting enzymes like DNA polymerase and reverse transcriptase. The antiviral properties of G. sanguineum L. seem to complement its immunomodulatory effects, contributing to infection resolution. While preclinical studies on G. sanguineum L. suggest its potential effectiveness against COVID-19, there is still a lack of clinical evidence. Therefore, the polyphenols extracted from this herb warrant further investigation as a potential alternative for preventing and treating COVID-19 infections.

Structural characterization of polysaccharides from Geranium sanguineum L. and their immunomodulatory effects in response to inflammatory agents

ETHNOPHARMACOLOGICAL RELEVANCE

Geranium sanguineum L. is used for treatment of inflammations, anemia, malignant diseases of the blood-forming organs, diarrhea, respiratory infections, etc. Only flavonoids in root extracts have been elucidated as immunostimulating and anti-inflammatory compounds, and polysaccharides in the herb have not been examined.

AIM OF THE STUDY

to compare the chemical features of polysaccharide complexes (PSCs) from leaves (GSL-PSC) and roots (GSR-PSC) of G. sanguineum, as well as their immunomodulatory activities on leukocytes after inflammation, and effects on the growth of different bacteria.

MATERIALS AND METHODS

The samples were isolated by water extraction and their structural features were studied by 2D NMR spectroscopy. The stimulatory effects of both PSCs on human leukocytes were analyzed with flow cytometry. Their suppressive activities on the oxidative burst in blood and derived neutrophils against opsonized zymosan and phorbol myristate acetate were investigated. The effects of the samples on viability, NO and interleukin 6 (IL-6) syntheses in RAW264.7 cells after inflammation with lipopolysaccharides (LPS) were tested. The prebiotic and anti-biofilm activities of the PSCs were evaluated.

RESULTS

The total carbohydrate content in the samples was significant (73.6-76.8%). GSL-PSC contained pectins, which were rich in homogalacturonan (HG), and smaller amounts of rhamnogalacturonan (RG) type I, decorated by 1,5-α-L-Araf, 1,4- and 1,6-β-D-Galp chains. GSR-PSC contained starch, followed by pectins with lower HG content and more RG-I regions, substituted by 1 → 3,5-α-L-arabinans and 1 → 3,6-β-D-galactans. GSL-PSC and GSR-PSC (200 μg/mL) increased monocyte and granulocyte cell counts, but GSR-PSC also elevated T helper and B cell levels in a normal and activated state. GSR-PSC triggered a dose-dependent (50-200 μg/mL) oxidative burst in blood, but alleviated it after inflammation even in blood-derived neutrophils. It was free of LPS, and activated NO and IL-6 productions in RAW264.7 cells better than GSL-PSC, without affecting their viability. Both PSCs (2.0%, w/v) stimulated probiotic co-cultures between Clostridium beijerinckii strains and Lactobacillus sp. ZK9, and inhibited the growth and biofilm formation of Escherichia coli, Streptococcus mutans and Salmonella enterica.

CONCLUSIONS

The PSs in G. sanguineum could be involved in the stimulatory effects on blood-forming organs and anti-inflammatory action of aqueous root extracts in case of infections. These PSs should be included in synbiotic foods to support the treatment of inflammations and infections in the gut.

Bioactivity of the Geranium Genus: A Comprehensive Review

BACKGROUND

Plants from the Geranium genus, which comprises about 400 species, have been used since ancient times in the practice of traditional medicines throughout the world. Therefore, herbal preparations based on Geranium species have found wide usage for the treatment of a variety of ailments. The aim of this work is to present a review, as comprehensive as possible, of the studies concerning different biological activities of Geranium species.

METHODS

Relevant data were obtained through systematic computer searches from major reputed scientific databases, particularly Web of Science and Scopus. Occasionally, information issued in primary sources not covered by these databases was also included provided published as peer-reviewed literature. This review covers the literature disclosed till the end of 2018.

RESULTS

Accompanying the increasing interest in herbal medicines in general, the evaluation of the biological properties of medicinal plants from the Geranium genus has been addressed thoroughly, mostly over the last two decades. Geranium species are endowed with a number of different biological activities. Herein, we present a survey of the results of the studies concerning these different biological activities.

CONCLUSION

Most studies found in the literature effectively contribute to scientifically validate the beneficial properties of Geranium plants claimed by traditional medicines and medical herbalism and demonstrate that many of them possess evident therapeutic properties.

The preventive and therapeutic potential of natural polyphenols on influenza

Influenza virus belongs to orthomyxoviridae family. This virus is a major public health problems, with high rates of morbidity and mortality. Despite a wide range of pharmacotherapeutic choices inhibiting specific sequences of pathological process of influenza, developing more effective therapeutic options is an immediate challenge. In this paper, a comprehensively review of natural polyphenolic products used worldwide for the management of influenza infection is presented. Cellular and molecular mechanisms of the natural polyphenols on influenza infection including suppressing virus replication cycle, viral hemagglutination, viral adhesion and penetration into the host cells, also intracellular transductional signaling pathways have been discussed in detail. Based on cellular, animal, and human evidence obtained from several studies, the current paper demonstrates that natural polyphenolic compounds possess potential effects on both prevention and treatment of influenza, which can be used as adjuvant therapy with conventional chemical drugs for the management of influenza and its complications.

New functionally-enhanced soy proteins as food ingredients with anti-viral activity

Respiratory viruses are a major public health problem because of their prevalence and high morbidity rate leading to considerable social and economic implications. Cranberry has therapeutic potential attributed to a comprehensive list of phytochemicals including anthocyanins, flavonols, and unique A-type proanthocyanidins. Soy flavonoids, including isoflavones, have demonstrated anti-viral effects in vitro and in vivo. Recently, it was demonstrated that edible proteins can efficiently sorb and concentrate cranberry polyphenols, including anthocyanins and proanthocyanins, providing greatly stabilized matrices suitable for food products. The combination of cranberry and soy phytoactives may be an effective dietary anti-viral resource. Anti-viral properties of both cranberry juice-enriched and cranberry pomace polyphenol-enriched soy protein isolate (CB-SPI and CBP-SPI) were tested against influenza viruses (H7N1, H5N3, H3N2), Newcastle disease virus and Sendai virus in vitro and in ovo. In our experiments, preincubation with CB-SPI or CBP-SPI resulted in inhibition of virus adsorption to chicken red blood cells and reduction in virus nucleic acid content up to 16-fold, however, CB-SPI and CBP-SPI did not affect hemagglutination. Additionally, CB-SPI and CBP-SPI inhibited viral replication and infectivity more effectively than the commercially available anti-viral drug Amizon. Results suggest CB-SPI and CBP-SPI may have preventative and therapeutic potential against viral infections that cause diseases of the respiratory and gastro-intestinal tract.

Amantadine and rimantadine for influenza A in children and the elderly

BACKGROUND

Influenza is an acute respiratory illness caused by influenza A and B viruses. Complications may occur, especially among children and the elderly.

OBJECTIVES

To assess the effectiveness and safety of amantadine and rimantadine in preventing, treating and shortening the duration of influenza A in children and the elderly.

SEARCH METHODS

We searched CENTRAL (2014, Issue 9), MEDLINE (1966 to September week 4, 2014) and EMBASE (1980 to October 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing amantadine and/or rimantadine with no intervention, placebo, other antivirals or different doses or schedules of amantadine or rimantadine in children and the elderly with influenza A.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the search results. We extracted and analysed data using the standard Cochrane methodology.

MAIN RESULTS

We identified 12 studies (2494 participants: 1586 children and 908 elderly) comparing amantadine and rimantadine with placebo, paracetamol (one trial: 69 children) or zanamivir (two trials: 545 elderly) to treat influenza A.Amantadine was effective in preventing influenza A in children (773 participants, risk ratio (RR) 0.11; 95% confidence interval (CI) 0.04 to 0.30). The assumed risk of influenza A in the control group was 10 per 100. The corresponding risk in the rimantadine group was one per 100 (95% CI 0 to 3). Nevertheless, the quality of the evidence was low and the safety of the drug was not well established.For treatment, rimantadine was beneficial in abating fever on day three of treatment in children: one selected study with low risk of bias, moderate evidence quality and 69 participants (RR 0.36; 95% CI 0.14 to 0.91). The assumed risk was 38 per 100. The corresponding risk in the rimantadine group was 14 per 100 (95% CI 5 to 34).Rimantadine did not show any prophylactic effect in the elderly. The quality of evidence was very low: 103 participants (RR 0.45; 95% CI 0.14 to 1.41). The assumed risk was 17 per 100. The corresponding risk in the rimantadine group was 7 per 100 (95% CI 2 to 23).There was no evidence of adverse effects caused by treatment with amantadine or rimantadine.We found no studies assessing amantadine in the elderly.

AUTHORS' CONCLUSIONS

The quality of the evidence combined with a lack of knowledge about the safety of amantadine and the limited benefits of rimantadine, do not indicate that amantadine and rimantadine compared to control (placebo or paracetamol) could be useful in preventing, treating and shortening the duration of influenza A in children and the elderly.

PI3K/Akt signaling pathway modulates influenza virus induced mouse alveolar macrophage polarization to M1/M2b

Macrophages polarized to M1 (pro-inflammation) or M2 (anti-inflammation) phenotypes in response to environmental signals. In this study, we examined the polarization of alveolar macrophage (AM), following induction by different influenza virus strains (ST169 (H1N1), ST602 (H3N2) and HKG9 (H9N2)). Macrophages from other tissues or cell line exert alternative responding pattern, and AM is necessary for investigating the respiratory system. AM polarized toward the M1 phenotype after 4 hours of infection by all three virus strains, and AM to presented M2b phenotype after 8 hours induction, and immunosuppressive phenotype after 24 hours of induction. Protein expression assay showed similar results as the gene expression analysis for phenotype verification. The ELISA assay showed that TNF-α secretion was up-regulated after 4 and 8 hours of infection by influenza viruses, and it returned to basal levels after 24 hours of infection. IL-10 expression was elevated after 8 and 24 hours of infection. Immunofluorescence showed that iNOS expression was up-regulated but not Arg1 expression. Influenza virus notably increased phospho-Akt but not phospho-Erk1/2 or phospho-p38, and the AM polarization pattern have been changed by LY294002 (PI3K inhibitor). In conclusion, our results demonstrate the dynamic polarization of AM induced by influenza viruses, and suggested that PI3K/Akt signaling pathway modulates AM polarization to M1/M2b.

Amantadine and rimantadine for influenza A in children and the elderly

BACKGROUND

The effectiveness and safety of amantadine (AMT) and rimantadine (RMT) for preventing and treating influenza A in adults has been systematically reviewed. However, little is known about these treatments in children and the elderly.

OBJECTIVES

To systematically review the effectiveness and safety of AMT and RMT in preventing and treating influenza A in children and the elderly.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 2) which contains the Cochrane Acute Respiratory Infections (ARI) Group's Specialised Register, MEDLINE (1966 to June week 3, 2011) and EMBASE (1980 to June 2011).

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing AMT and/or RMT with placebo, control, other antivirals or different doses or schedules of AMT or RMT, or both, or no intervention, in children and the elderly.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and assessed methodological quality. We resolved disagreements by consensus. In all comparisons except for one, we separately analysed the trials in children and the elderly using Review Manager software.

MAIN RESULTS

A total of 12 studies involving 2494 participants (1586 children and adolescents and 908 elderly) compared AMT and RMT with placebo, paracetamol (one trial; 69 children) or zanamivir (two trials; 545 seniors). All studies were RCTs but most were still susceptible to bias. Two trials in the elderly had a high risk of bias because of incomplete outcome data. In one of those trials there was also a lack of outcome assessment blinding. Risk of bias was unclear in 10 studies due to unclear random sequence generation and allocation concealment. Only two trials in children were considered to have a low risk of bias.AMT was effective in preventing influenza A in children. A total of 773 participants were included in this outcome (risk ratio (RR) 0.11; 95% confidence interval (CI) 0.04 to 0.30). The assumed risk of influenza in the control group was 10 per 100 and the corresponding risk in the RMT group was one per 100 (95% CI 0 to 3). The quality of the evidence was considered low. For treatment purposes, RMT was beneficial for abating fever on day three of treatment. For this purpose one study was selected with low risk of bias and included 69 children (RR 0.36; 95% CI 0.14 to 0.91). The assumed risk was 38 per 100 and the corresponding risk in the RMT group was 14 per 100, 95% CI 5 to 34. The quality of the evidence was moderate.RMT did not show a prophylactic effect against influenza in the elderly, but the quality of evidence was considered very low. There were 103 participants (RR 0.45; 95% CI 0.14 to 1.41, for an assumed risk of 17 per 100 and a corresponding risk in the RMT group of 7 per 100, 95% CI 2 to 23). We did not identify any AMT trials in the elderly that met our inclusion criteria.There was no evidence of adverse effects of AMT and RMT in children or an adverse effect of RMT in the elderly. We did not identify any AMT trials in the elderly that met our inclusion criteria.

AUTHORS' CONCLUSIONS

AMT is effective in preventing influenza A in children but the NNTB is high (NNTB: 12 (95% CI 9 to 17). RMT probably helps the abatement of fever on day three of treatment, but the quality of the evidence is poor. Due to the small number of available studies, we could not reach a definitive conclusion on the safety of AMT or the effectiveness of RMT in preventing influenza in children and the elderly.

Novel signaling interactions between proteinase-activated receptor 2 and Toll-like receptors in vitro and in vivo

Toll-like receptors (TLRs) and proteinase-activated receptors (PARs) function as innate immune biosensors in mucosal epithelial cells (ECs). We previously reported the functional and physical interactions between TLR4 and PAR(2). We have extended these findings herein by showing the cooperation between PAR(2) and TLR2, TLR3, or TLR4 for activation of nuclear factor-kappaB-dependent signaling in mucosal EC lines. In contrast, activation of PAR(2) negatively regulated TLR3-dependent antiviral pathway, blunting the expression of TLR3/interferon regulatory factor-3 (IRF-3)-driven genes, as well as activation of IRF-3 and STAT1. Consistent with these in vitro observations, PAR(2)(-/-) and TLR4(-/-) mice, which were refractory to footpad edema induced by PAR(2) agonist peptide, were protected from mouse-adapted H1N1 influenza A virus-induced lethality when compared to wild-type (WT) mice. These data support and extend our recently described, novel model of PAR(2)-TLR4 "receptor cooperativity" and highlight the complexity of signaling integration between heterologous innate immune biosensors.

Amantadine and rimantadine for influenza A in children and the elderly

BACKGROUND

Although amantadine (AMT) and rimantadine (RMT) are used to relieve or treat influenza A symptoms in healthy adults, little is known about the effectiveness and safety of these antivirals in preventing and treating influenza A in children and the elderly.

OBJECTIVES

The aim of this review was to systematically consider evidence on the effectiveness and safety of AMT and RMT in preventing and treating influenza A in children and the elderly.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2007, issue 3); MEDLINE (1966 to July 2007) and EMBASE (1980 to July 2007).

SELECTION CRITERIA

Randomised or quasi-randomised trials comparing AMT and/or RMT in children and the elderly with placebo, control, other antivirals or comparing different doses or schedules of AMT and/or RMT or no intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and assessed methodological quality. Disagreements were resolved by consensus. In all comparisons except for one, the trials in children and in the elderly were analysed separately. Data were analysed and reported using Cochrane Review Manager 4.2. software.

MAIN RESULTS

In children, RMT was effective in the abatement of fever on day three of treatment. AMT showed a prophylactic effect against influenza A infection. AMT and RMT were not related to an increase in the occurrence of adverse effects. RMT also was considered to be well tolerated by the elderly, but showed no prophylactic effect. Different doses were comparable in the prophylaxis of influenza in the elderly, as well as in reporting adverse effects. Zanamivir prevented influenza A more effectively than RMT in the elderly.

AUTHORS' CONCLUSIONS

AMT was effective in the prophylaxis of influenza A in children. As confounding matters might have affected our findings, caution should be taken when considering which patients should to be given this prophylactic. Our conclusions about effectiveness of both antivirals for the treatment of influenza A in children were limited to a proven benefit of RMT in the abatement of fever on day three of treatment. Due to the small number of available studies we could not reach a definitive conclusion on the safety of AMT or the effectiveness of RMT in preventing influenza in children and the elderly.