Curcumin ameliorates severe influenza pneumonia via attenuating lung injury and regulating macrophage cytokines production

Curcumin as a natural potential drug candidate against important zoonotic viruses and prions: A narrative review

Zoonotic diseases are major public health concerns and undeniable threats to human health. Among Zoonotic diseases, zoonotic viruses and prions are much more difficult to eradicate, as they result in higher infections and mortality rates. Several investigations have shown curcumin, the active ingredient of turmeric, to have wide spectrum properties such as anti-microbial, anti-vascular, anti-inflammatory, anti-tumor, anti-neoplastic, anti-oxidant, and immune system modulator properties. In the present study, we performed a comprehensive review of existing in silico, in vitro, and in vivo evidence on the antiviral (54 important zoonotic viruses) and anti-prion properties of curcumin and curcuminoids in PubMed, Google Scholar, Science Direct, Scopus, and Web of Science databases. Database searches yielded 13,380 results, out of which 216 studies were eligible according to inclusion criteria. Of 216 studies, 135 (62.5%), 24 (11.1%), and 19 (8.8%) were conducted on the effect of curcumin and curcuminoids against SARS-CoV-2, Influenza A virus, and dengue virus, respectively. This review suggests curcumin and curcuminoids as promising therapeutic agents against a wide range of viral zoonoses by targeting different proteins and signaling pathways.

Evolution of radiation-induced dermatitis treatment

Radiation-induced skin damage (RID) is the most prevalent, significant side effect of radiotherapy (RT). Nearly 95% of patients experience moderate to severe skin reactions after receiving radiation therapy. However, criteria for acute radiation dermatitis (ARD) treatment remain unavailable. Topical agents with anti-inflammatory properties may protect the skin and facilitate tissue regeneration in patients with RID. Many of these topical agents function through nuclear factor kappa B pathway regulation. They either reduce the levels of inflammatory factors or elicit anti-inflammatory properties of their own, thus preventing oxidative stress and inflammatory responses and thus enabling RID prevention and management. Herein, we explore the 25 topical agents investigated for RID prevention and management thus far and evaluate their mechanisms of action. These agents include 11 natural agents, 3 miscellaneous agents, 9 topical nonsteroidal agents, and 2 topical corticosteroids.

Epigallocatechin-3-Gallate attenuates lipopolysacharide-induced pneumonia via modification of inflammation, oxidative stress, apoptosis, and autophagy

BACKGROUND

Pneumonia, the acute inflammation of lung tissue, is multi-factorial in etiology. Hence, continuous studies are conducted to determine the mechanisms involved in the progression of the disease and subsequently suggest effective treatment. The present study attempted to evaluate the effects of Epigallocatechin-3-Gallate (EGCG), an herbal antioxidant, on inflammation, oxidative stress, apoptosis, and autophagy in a rat pneumonia model.

METHODS

Forty male Wistar rats, 5 months old and 250-290 g were divided into four groups including control, EGCG, experimental pneumonia (i/p LPS injection, 1 mg/kg), and experimental pneumonia treated with EGCG (i/p, 15 mg/kg, 1 h before and 3 h after LPS instillation). Total cell number in the bronchoalveolar lavage fluid, inflammation (TNF-a, Il-6, IL-1β, and NO), oxidative stress (Nrf2, HO-1, SOD, CAT, GSH, GPX, MDA, and TAC), apoptosis (BCL-2, BAX, CASP-3 and CASP-9), and autophagy (mTOR, LC3, BECN1) were evaluated.

RESULTS

The findings demonstrated that EGCG suppresses the LPS-induced activation of inflammatory pathways by a significant reduction of inflammatory markers (p-value < 0.001). In addition, the upregulation of BCL-2 and downregulation of BAX and caspases revealed that EGCG suppressed LPS-induced apoptosis. Furthermore, ECGC suppressed oxidative injury while promoting autophagy in rats with pneumonia (p-value < 0.05).

CONCLUSION

The current study revealed that EGCG could suppress inflammation, oxidative stress, apoptosis, and promote autophagy in experimental pneumonia models of rats suggesting promising therapeutical properties of this compound to be used in pneumonia management.

Plant-Derived Natural Compounds as an Emerging Antiviral in Combating COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a human virus that burst at Wuhan in China and spread quickly over the world, leading to millions of deaths globally. The journey of this deadly virus to different mutant strains is still ongoing. The plethora of drugs and vaccines have been tested to cope up this pandemic. The herbal plants and different spices have received great attention during pandemic, because of their anti-inflammatory, and immunomodulatory properties in treating viruses and their symptoms. Also, it has been shown that nano-formulation of phytochemicals has potential therapeutic effect against COVID-19. Furthermore, the plant derived compound nano-formulation specifically increases its antiviral property by enhancing its bioavailability, solubility, and target-specific delivery system. This review highlights the potentiality of herbal plants and their phytochemical against SARS-CoV-2 utilizing different mechanisms such as blocking the ACE-2 receptors, inhibiting the main proteases, binding spike proteins and reducing the cytokine storms.

Efficacy of Nanocurcumin as an Add-On Treatment for Patients Hospitalized with COVID-19: A Double-Blind, Randomized Clinical Trial

Background

Curcumin is a polyphenol derivative of the Curcuma longa rhizome, with potential antioxidant, anticancer, antidepressant, antiviral, and anti-inflammatory effects. This compound can be prepared as biodegradable polymer nanoparticles, called nanocurcumin, to improve its solubility, stability, half-life, and bioavailability.

Aim

We explored nanocurcumin's effect on the clinical manifestations of patients hospitalized with mild-to-moderate COVID-19.

Methods

This double-blind, randomized clinical trial involved 76 COVID-19 patients admitted to Ali-Asghar Hospital from December 2021 to March 2022. All patients received standard coronavirus treatment as per national guidelines. In addition, four times a day for two weeks, the curcumin group received 40 mg of nanocurcumin, while the control group received a placebo. Clinical manifestations were examined and recorded by the associate doctors working in the department. Statistical analysis was done using SPSS v. 21.

Results

Thirty-nine people from the control group and 29 from the curcumin group completed the study. At baseline, the groups were comparable in age, gender, body mass index, hospitalization duration, and background diseases. The mean age of patients in the control and treatment groups was 53.9 ± 11.9 and 54.6 ± 13.4, respectively. Compared with the placebo, nanocurcumin minimized coughs (P=0.036), fatigue (P=0.0001), myalgia (P=0.027), oxygen demand (P=0.036), oxygen usage (P=0.05), and respiratory rate (P < 0.0001). By discharge, the curcumin group had a significantly greater increase in SPO2 than the control group (P=0.006).

Conclusions

This preliminary study suggests that nanocurcumin has a potentiating anti-inflammatory effect when combined with standard COVID-19 treatment, helping the recovery from the acute inflammatory phase of the disease in hospitalized patients with mild-to-moderate disease severity. This trial is registered with Iranian Registry of Clinical Trials: IRCT20211126053183N1 (registered while recruiting on 13/12/2021).

NASAFYTOL® supplementation in adults hospitalized with COVID-19 infection: results from an exploratory open-label randomized controlled trial

Objectives

The effect and safety of Nasafytol^®, a food supplement combining curcumin, quercetin, and Vitamin D, on hospitalized COVID-19-positive patients as support to standard of care were to be assessed.

Methods

This exploratory, open-label, randomized, controlled trial was carried out among hospitalized adults with COVID-19 infection. Participants were randomly assigned to receive Nasafytol^® or Fultium^® control. The improvement of the clinical condition and occurrence of (serious) adverse events were evaluated. The study was registered on clincaltrials.gov with the identifier NCT04844658.

Results

Twenty-five patients received Nasafytol^®, and 24 received Fultium^®. Demographic characteristics were well balanced between the groups. On day 14 (or at hospital leave if < 14 days), no difference was observed between groups regarding their clinical condition, fever, or the need of oxygen therapy. At day 7, however, 19 participants had been discharged from the hospital in the Nasafytol^® arm compared to 10 participants in the Fultium^® arm. No participants were transferred to the ICU or died in the Nasafytol^® arm, vs. 4 transfers and 1 death in the Fultium^® arm. The clinical condition of participants in the Nasafytol^® arm had improved, as evidenced by a decrease in the COVID-19 WHO score. Interestingly, five SAEs occurred with Fultium^®, while no SAE was observed with Nasafytol^®.

Conclusion

Supplementation with Nasafytol^®, in addition to standard-of-care treatment, led to a faster discharge from the hospital, improved clinical conditions of participants, and a reduced risk of serious outcomes, including transfer to the intensive care unit or death, in patients hospitalized with COVID-19.

Curcumin Confers Anti-Inflammatory Effects in Adults Who Recovered from COVID-19 and Were Subsequently Vaccinated: A Randomized Controlled Trial

COVID-19 infection and vaccination offer disparate levels of defense against reinfection and breakthrough infection. This study was designed to examine the effects of curcumin supplementation, specifically HydroCurc (CURC), versus placebo (CON) on circulating inflammatory biomarkers in adults who had previously been diagnosed with COVID-19 and subsequently received a primary series of monovalent vaccine doses. This study was conducted between June 2021 and May 2022. Participants were randomized to receive CURC (500 mg) or CON capsules twice daily for four weeks. Blood sampling was completed at baseline and week-4 and analyzed for biomarkers. Linear regression was utilized to examine the between-group differences in post-trial inflammatory biomarker levels, adjusting for baseline and covariates including age, sex, race/ethnicity, and interval between COVID-19 diagnosis and trial enrollment. The sample (n = 31) was 71% female (Age 27.6 ± 10.4 y). The CURC group exhibited significantly lower post-trial concentrations of proinflammatory IL-6 (β = -0.52, 95%CI: -1.03, -0.014, p = 0.046) and MCP-1 (β = -0.12, 95%CI: -0.23, -0.015, p = 0.027) compared to CON, adjusting for baseline and covariates. Curcumin intake confers anti-inflammatory activity and may be a promising prophylactic nutraceutical strategy for COVID-19. These results suggest that 4 weeks of curcumin supplementation resulted in significantly lower concentrations of proinflammatory cytokines in adults who recovered from COVID-19 infection and were subsequently vaccinated.

Modulatory properties of curcumin in cancer: A narrative review on the role of interferons

The immune network is an effective network of cell types and chemical compounds established to maintain the body's homeostasis from foreign threats and to prevent the risk of a wide range of diseases; hence, its proper functioning and balance are essential. A dysfunctional immune system can contribute to various disorders, including cancer. Therefore, there has been considerable interest in molecules that can modulate the immune network. Curcumin, the active ingredient of turmeric, is one of these herbal remedies with many beneficial effects, including modulation of immunity. Curcumin is beneficial in managing various chronic inflammatory conditions, improving brain function, lowering cardiovascular disease risk, prevention and management of dementia, and prevention of aging. Several clinical studies have supported this evidence, suggesting curcumin to have an immunomodulatory and anti-inflammatory function; nevertheless, its mechanism of action is still not clear. In the current review, we aim to explore the modulatory function of curcumin through interferons in cancers.

Anti-viral drug discovery against monkeypox and smallpox infection by natural curcumin derivatives: A Computational drug design approach

Background

In the last couple of years, viral infections have been leading the globe, considered one of the most widespread and extremely damaging health problems and one of the leading causes of mortality in the modern period. Although several viral infections are discovered, such as SARS CoV-2, Langya Henipavirus, there have only been a limited number of discoveries of possible antiviral drug, and vaccine that have even received authorization for the protection of human health. Recently, another virial infection is infecting worldwide (Monkeypox, and Smallpox), which concerns pharmacists, biochemists, doctors, and healthcare providers about another epidemic. Also, currently no specific treatment is available against Monkeypox. This research gap encouraged us to develop a new molecule to fight against monkeypox and smallpox disease. So, firstly, fifty different curcumin derivatives were collected from natural sources, which are available in the PubChem database, to determine antiviral capabilities against Monkeypox and Smallpox.

Material and method

Preliminarily, the molecular docking experiment of fifty different curcumin derivatives were conducted, and the majority of the substances produced the expected binding affinities. Then, twelve curcumin derivatives were picked up for further analysis based on the maximum docking score. After that, the density functional theory (DFT) was used to determine chemical characterizations such as the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), softness, and hardness, etc.

Results

The mentioned derivatives demonstrated docking scores greater than 6.80 kcal/mol, and the most significant binding affinity was at -8.90 kcal/mol, even though 12 molecules had higher binding scores (-8.00 kcal/mol to -8.9 kcal/mol), and better than the standard medications. The molecular dynamic simulation is described by root mean square deviation (RMSD) and root-mean-square fluctuation (RMSF), demonstrating that all the compounds might be stable in the physiological system.

Conclusion

In conclusion, each derivative of curcumin has outstanding absorption, distribution, metabolism, excretion, and toxicity (ADMET) characteristics. Hence, we recommended the aforementioned curcumin derivatives as potential antiviral agents for the treatment of Monkeypox and Smallpox virus, and more in vivo investigations are warranted to substantiate our findings.

COVID-19: Reducing the risk via diet and lifestyle

This review shows that relatively simple changes to diet and lifestyle can significantly, and rapidly, reduce the risks associated with coronavirus disease 2019 (COVID-19) in terms of infection risk, severity of disease, and even disease-related mortality. A wide range of interventions including regular exercise, adequate sleep, plant-based diets, maintenance of healthy weight, dietary supplementation, and time in nature have each been shown to have beneficial effects for supporting more positive health outcomes with COVID-19, in addition to promoting better overall health. This paper brings together literature from these areas and presents the argument that non-pharmaceutical approaches should not be overlooked in our response to COVID-19. It is noted that, in several cases, interventions discussed result in risk reductions equivalent to, or even greater than, those associated with currently available vaccines. Where the balance of evidence suggests benefits, and the risk is minimal to none, it is suggested that communicating the power of individual actions to the public becomes morally imperative. Further, many lives could be saved, and many harms from the vaccine mandates avoided, if we were willing to embrace this lifestyle-centred approach in our efforts to deal with COVID-19.

5-Methoxyflavone-induced AMPKα activation inhibits NF-κB and P38 MAPK signaling to attenuate influenza A virus-mediated inflammation and lung injury in vitro and in vivo

Influenza-related acute lung injury (ALI) is a life-threatening condition that results mostly from uncontrolled replication of influenza virus (IV) and severe proinflammatory responses. The methoxy flavonoid compound 5-methoxyflavone (5-MF) is believed to have superior biological activity in the treatment of cancer. However, the effects and underlying mechanism of 5-MF on IV-mediated ALI are still unclear. Here, we showed that 5-MF significantly improved the survival of mice with lethal IV infection and ameliorated IV-mediated lung edema, lung histological changes, and inflammatory cell lung recruitment. We found that 5-MF has antiviral activity against influenza A virus (IAV), which was probably associated with increased expression of radical S-adenosyl methionine domain containing 2 (RSAD2) and suppression of endosomal acidification. Moreover, IV-infected A549 cells with 5-MF treatment markedly reduced proinflammatory mediator expression (IL-6, CXCL8, TNF-α, CXCL10, CCL2, CCL3, CCL4, GM-CSF, COX-2, and PGE₂) and prevented P-IKBα, P-P65, and P-P38 activation. Interestingly, we demonstrated that 5-MF treatment could trigger activation of AMP-activated protein kinase (AMPK)α in IV-infected A549 cells, as evidenced by activation of the AMPKα downstream molecule P53. Importantly, the addition of AMPKα blocker compound C dramatically abolished 5-MF-mediated increased levels of RSAD2, the inhibitory effects on H1N1 virus-elicited endosomal acidification, and the suppression expression of proinflammatory mediators (IL-6, TNF-α, CXCL10, COX-2 and PGE₂), as well as the inactivation of P-IKBα, P-P65, and P-P38 MAPK signaling pathways. Furthermore, inhibition of AMPKα abrogated the protective effects of 5-MF on H1N1 virus-mediated lung injury and excessive inflammation in vivo. Taken together, these results indicate that 5-MF alleviated IV-mediated ALI and suppressed excessive inflammatory responses through activation of AMPKα signaling.

Reconnoitering the Therapeutic Role of Curcumin in Disease Prevention and Treatment: Lessons Learnt and Future Directions

Turmeric is a plant with a very long history of medicinal use across different cultures. Curcumin is the active part of turmeric, which has exhibited various beneficial physiological and pharmacological effects. This review aims to critically appraise the corpus of literature associated with the above pharmacological properties of curcumin, with a specific focus on antioxidant, anti-inflammatory, anticancer and antimicrobial properties. We have also reviewed the different extraction strategies currently in practice, highlighting the strengths and drawbacks of each technique. Further, our review also summarizes the clinical trials that have been conducted with curcumin, which will allow the reader to get a quick insight into the disease/patient population of interest with the outcome that was investigated. Lastly, we have also highlighted the research areas that need to be further scrutinized to better grasp curcumin’s beneficial physiological and medicinal properties, which can then be translated to facilitate the design of better bioactive therapeutic leads.

Curcumin and Its Analogs as a Therapeutic Strategy in Infections Caused by RNA Genome Viruses

The use of natural resources for the prevention and treatment of diseases considered fatal to humanity has evolved. Several medicinal plants have nutritional and pharmacological potential in the prevention and treatment of viral infections, among them, turmeric, which is recognized for its biological properties associated with curcuminoids, mainly represented by curcumin, and found mostly in rhizomes. The purpose of this review was to compile the pharmacological activities of curcumin and its analogs, aiming at stimulating their use as a therapeutic strategy to treat infections caused by RNA genome viruses. We revisited its historical application as an anti-inflammatory, antioxidant, and antiviral agent that combined with low toxicity, motivated research against viruses affecting the population for decades. Most findings concentrate particularly on arboviruses, HIV, and the recent SARS-CoV-2. As one of the main conclusions, associating curcuminoids with nanomaterials increases solubility, bioavailability, and antiviral effects, characterized by blocking the entry of the virus into the cell or by inhibiting key enzymes in viral replication and transcription.

Curcuma longa and curcumin affect respiratory and allergic disorders, experimental and clinical evidence: A comprehensive and updated review

Curcuma longa and its constituents, mainly curcumin, showed various of pharmacological effects in previous studies. This review article provides updated and comprehensive experimental and clinical evidence regarding the effects of C. longa and curcumin on respiratory, allergic, and immunologic disorders. Using appropriate keywords, databases including PubMed, Science Direct, and Scopus were searched until the end of October 2021. C. longa extracts and its constituent, curcumin, showed the relaxant effect on tracheal smooth muscle, which indicates their bronchodilatory effect in obstructive pulmonary diseases. The preventive effects of extracts of C. longa and curcumin were shown in experimental animal models of different respiratory diseases through antioxidant, immunomodulatory, and anti-inflammatory mechanisms. C. longa and curcumin also showed preventive effects on some lung disorders in the clinical studies. It was shown that the effects of C. longa on pulmonary diseases were mainly due to its constituent, curcumin. Pharmacological effects of C. longa extracts and curcumin on respiratory, allergic, and immunologic disorders indicate the possible therapeutic effect of the plant and curcumin on these diseases.

Antimicrobial Potential of Curcumin: Therapeutic Potential and Challenges to Clinical Applications

Curcumin is a bioactive compound that is extracted from Curcuma longa and that is known for its antimicrobial properties. Curcuminoids are the main constituents of curcumin that exhibit antioxidant properties. It has a broad spectrum of antibacterial actions against a wide range of bacteria, even those resistant to antibiotics. Curcumin has been shown to be effective against the microorganisms that are responsible for surgical infections and implant-related bone infections, primarily Staphylococcus aureus and Escherichia coli. The efficacy of curcumin against Helicobacter pylori and Mycobacterium tuberculosis, alone or in combination with other classic antibiotics, is one of its most promising antibacterial effects. Curcumin is known to have antifungal action against numerous fungi that are responsible for a variety of infections, including dermatophytosis. Candidemia and candidiasis caused by Candida species have also been reported to be treated using curcumin. Life-threatening diseases and infections caused by viruses can be counteracted by curcumin, recognizing its antiviral potential. In combination therapy with other phytochemicals, curcumin shows synergistic effects, and this approach appears to be suitable for the eradication of antibiotic-resistant microbes and promising for achieving co-loaded antimicrobial pro-regenerative coatings for orthopedic implant biomaterials. Poor water solubility, low bioavailability, and rapid degradation are the main disadvantages of curcumin. The use of nanotechnologies for the delivery of curcumin could increase the prospects for its clinical application, mainly in orthopedics and other surgical scenarios. Curcumin-loaded nanoparticles revealed antimicrobial properties against S. aureus in periprosthetic joint infections.

Pulsed blue light, saliva and curcumin significantly inactivate human coronavirus

In a recent study, we showed that pulsed blue light (PBL) inactivates as much as 52.3% of human beta coronavirus HCoV-OC43, a surrogate of SARS-CoV-2, and one of the major strains of viruses responsible for the annual epidemic of the common cold. Since curcumin and saliva are similarly antiviral and curcumin acts as blue light photosensitizer, we used Qubit fluorometry and WarmStart RT-LAMP assays to study the effect of combining 405 nm, 410 nm, 425 nm or 450 nm wavelengths of PBL with curcumin, saliva or a combination of curcumin and saliva against human beta coronavirus HCoV-OC43. The results showed that PBL, curcumin and saliva independently and collectively inactivate HCoV-OC43. Without saliva or curcumin supplementation 21.6 J/cm2 PBL reduced HCoV-OC43 RNA concentration a maximum of 32.8% (log10 = 2.13). Saliva supplementation alone inactivated the virus, reducing its RNA concentration by 61% (log10 = 2.23); with irradiation the reduction was as much as 79.1%. Curcumin supplementation alone decreased viral RNA 71.1%, and a maximum of 87.8% with irradiation. The combination of saliva and curcumin reduced viral RNA to 83.1% and decreased the RNA up to 90.2% with irradiation. The reduced levels could not be detected with qPCR. These findings show that PBL in the range of 405 nm to 450 nm wavelength is antiviral against human coronavirus HCoV-OC43, a surrogate of the COVID-19 virus. Further, it shows that with curcumin as a photosensitizer, it is possible to photodynamically inactivate the virus beyond qPCR detectable level using PBL. Since HCoV-OC43 is of the same beta coronavirus family as SARS-CoV-2, has the same genomic size, and is often used as its surrogate, these findings heighten the prospect of similarly inactivating novel coronavirus SARS-CoV-2, the virus responsible for COVID-19 pandemic.

Modulation of neutrophil (dys)function by Ayurvedic herbs and its potential influence on SARS-CoV-2 infection

For centuries, traditional medicines of Ayurveda have been in use to manage infectious and non-infectious diseases. The key embodiment of traditional medicines is the holistic system of approach in the management of human diseases. SARS-CoV-2 (COVID-19) infection is an ongoing pandemic, which has emerged as the major health threat worldwide and is causing significant stress, morbidity and mortality. Studies from the individuals with SARS-CoV-2 infection have shown significant immune dysregulation and cytokine overproduction. Neutrophilia and neutrophil to lymphocyte ratio has been correlated to poor outcome due to the disease. Neutrophils, component of innate immune system, upon stimulation expel DNA along with histones and granular proteins to form extracellular traps (NETs). Although, these DNA lattices possess beneficial activity in trapping and eliminating pathogens, NETs may also cause adverse effects by inducing immunothrombosis and tissue damage in diseases including Type 2 Diabetes and atherosclerosis. Tissues of SARS-CoV-2 infected subjects showed microthrombi with neutrophil-platelet infiltration and serum showed elevated NETs components, suggesting large involvement and uncontrolled activation of neutrophils leading to pathogenesis and associated organ damage. Hence, traditional Ayurvedic herbs exhibiting anti-inflammatory and antioxidant properties may act in a manner that might prove beneficial in targeting over-functioning of neutrophils and there by promoting normal immune homeostasis. In the present manuscript, we have reviewed and discussed pathological importance of NETs formation in SARS-CoV-2 infections and discuss how various Ayurvedic herbs can be explored to modulate neutrophil function and inhibit NETs formation in the context of a) anti-microbial activity to enhance neutrophil function, b) immunomodulatory effects to maintain neutrophil mediated immune homeostasis and c) to inhibit NETs mediated thrombosis.

Antiinflammatory phytochemicals against virus-induced hyperinflammatory responses: Scope, rationale, application, and limitations

Uncontrolled inflammatory responses or cytokine storm associated with viral infections results in deleterious consequences such as vascular leakage, severe hemorrhage, shock, immune paralysis, multi-organ failure, and even death. With the emerging new viral infections and lack of effective prophylactic vaccines, evidence-based complementary strategies that limit viral infection-mediated hyperinflammatory responses could be a promising approach to limit host tissue injury. The present review emphasizes the potentials of antiinflammatory phytochemicals in limiting hyperinflammatory injury caused by viral infections. The predominant phytochemicals along with their mechanism in limiting hyperimmune and pro-inflammatory responses under viral infection have been reviewed comprehensively. How certain phytochemicals can be effective in limiting hyper-inflammatory response indirectly by favorably modulating gut microbiota and maintaining a functional intestinal barrier has also been presented. Finally, we have discussed improved systemic bioavailability of phytochemicals, efficient delivery strategies, and safety measures for effective antiinflammatory phytotherapies, in addition to emphasizing the requirement of tightly controlled clinical studies to establish the antiinflammatory efficacy of the phytochemicals. Collectively, the review provides a scooping overview on the potentials of bioactive phytochemicals to mitigate pro-inflammatory injury associated with viral infections.

COVID-19, cytokines, inflammation, and spices: How are they related?

BACKGROUND

Cytokine storm is the exaggerated immune response often observed in viral infections. It is also intimately linked with the progression of COVID-19 disease as well as associated complications and mortality. Therefore, targeting the cytokine storm might help in reducing COVID-19-associated health complications. The number of COVID-19 associated deaths (as of January 15, 2021; https://www.worldometers.info/coronavirus/) in the USA is high (1199/million) as compared to countries like India (110/million). Although the reason behind this is not clear, spices may have some role in explaining this difference. Spices and herbs are used in different traditional medicines, especially in countries such as India to treat various chronic diseases due to their potent antioxidant and anti-inflammatory properties.

AIM

To evaluate the literature available on the anti-inflammatory properties of spices which might prove beneficial in the prevention and treatment of COVID-19 associated cytokine storm.

METHOD

A detailed literature search has been conducted on PubMed for collecting information pertaining to the COVID-19; the history, origin, key structural features, and mechanism of infection of SARS-CoV-2; the repurposed drugs in use for the management of COVID-19, and the anti-inflammatory role of spices to combat COVID-19 associated cytokine storm.

KEY FINDINGS

The literature search resulted in numerous in vitro, in vivo and clinical trials that have reported the potency of spices to exert anti-inflammatory effects by regulating crucial molecular targets for inflammation.

SIGNIFICANCE

As spices are derived from Mother Nature and are inexpensive, they are relatively safer to consume. Therefore, their anti-inflammatory property can be exploited to combat the cytokine storm in COVID-19 patients. This review thus focuses on the current knowledge on the role of spices for the treatment of COVID-19 through suppression of inflammation-linked cytokine storm.

A triple-blind, placebo-controlled, randomized clinical trial to evaluate the effect of curcumin-containing nanomicelles on cellular immune responses subtypes and clinical outcome in COVID-19 patients

In COVID-19 patients, cytokine storm due to excessive immune responses can cause severe complications. In this study, we investigated the effect of curcumin nanomicelles on clinical outcome and cellular immune responses subtypes changes in COVID-19 patients. A randomized, triple-blinded, placebo-controlled study was done. Forty COVID-19 patients were included into two groups of nano-curcumin and placebo. The nano-curcumin group received 40 mg of nano-curcumin capsule, four times per day for 2 weeks. Clinical signs and gene expression of TBX21, GATA3, RORC and FOXP3 genes and IFN-γ, IL-4, IL-17 and TGF-β cytokines serum levels were measured at time points of 0, 7 and 14 days. Serum levels of IFN-γ (p = .52) and IL-17 (p = .11) decreased, while IL-4 (p = .12) and TGF-β (p = .14) increased in the nano-curcumin group compared with placebo on day 14. Moreover, gene expressions of TBX21 (p = .02) and FOXP3 (p = .005) genes were significantly decreased and increased between nano-curcumin and placebo groups on day 7, respectively. It can be concluded that administration of nano-curcumin in inflammatory phase of COVID-19 can accelerate recovering of the acute inflammatory phase by modulating inflammatory immune responses. Therefore, it is suggested that this supplement in inflammatory diseases, including COVID-19, can be effective in controlling the inflammatory responses.

Potential Immunomodulatory Properties of Biologically Active Components of Spices Against SARS-CoV-2 and Pan β-Coronaviruses

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced COVID-19 has emerged as a defining global health crisis in current times. Data from the World Health Organization shows demographic variations in COVID-19 severity and lethality. Diet may play a significant role in providing beneficial host cell factors contributing to immunity against deadly SARS-CoV-2 pathogenesis. Spices are essential components of the diet that possess anti-inflammatory, antioxidant, and antiviral properties. Hyperinflammation, an aberrant systemic inflammation associated with pneumonia, acute respiratory failure, and multiorgan dysfunction, is a major clinical outcome in COVID-19. Knowing the beneficial properties of spices, we hypothesize that spice-derived bioactive components can modulate host immune responses to provide protective immunity in COVID-19. This study emphasizes that biologically active components of spices might alleviate the sustained pro-inflammatory condition by inhibiting the activity of tumor necrosis factor-alpha (TNF-α), interleukins (IL6, IL8), and chemokine (CCL2) known to be elevated in COVID-19. Spices may potentially prevent the tissue damage induced by oxidative stress and pro-inflammatory mediators during SARS-CoV-2 infection. The current study also highlights the effects of spices on the antioxidant pathways mediated by Nrf2 (nuclear factor erythroid 2-related factor 2) and Hmox1 (heme oxygenase 1) to restore oxidative homeostasis and protect from aberrant tissue damage. Taken together, the anti-inflammatory and antioxidant activities of bioactive components of spices may hold a promise to target the cellular pathways for developing antivirals against SARS-CoV-2 and pan β-coronaviruses.

Newly Developed Highly Bioavailable Curcumin Formulation, curcuRougeTM, Reduces Neutrophil/Lymphocyte Ratio in the Elderly: A Double-Blind, Placebo-Controlled Clinical Trial

Elevated neutrophil/lymphocyte ratio (NLR) has been reported as a sensitive marker for predicting poor prognosis in chronic inflammation-based diseases such as stroke, heart failure, cancers, and diabetes, as well as acute inflammatory diseases such as bacterial and viral infections, including COVID-19. NLR is also known to increase with age and is considered to be an aging marker. We conducted a double-blind, placebo-controlled trial in elderly volunteers to examine the effect of a newly developed, highly bioavailable curcumin formulation (curcuRouge^TM) on NLR. Both the white blood cell count and the neutrophil rate decreased significantly, and the lymphocyte rate increased significantly from baseline to after curcuRouge^TM administration for 4 wk. curcuRouge^TM significantly reduced the NLR (p=0.020). On the other hand, in the placebo group, there were no changes in white blood cell count, neutrophil ratio, lymphocyte ratio, or NLR. The present study demonstrates for the first time, in elderly volunteers, that administration of curcuRouge^TM significantly reduces NLR, an indicator of prognosis in cardiovascular diseases, cancer, infectious diseases, and aging. Thus, curcuRouge^TM might be expected to improve the prognosis of these diseases as well as exhibit anti-aging effects.

Elucidating the Effects of Curcumin against Influenza Using In Silico and In Vitro Approaches

The influenza virus is a constantly evolving pathogen that challenges medical and public health systems. Traditionally, curcumin has been used to treat airway inflammatory diseases, such as bronchitis and pneumonia. To elucidate common targets of curcumin and influenza infection and underlying mechanisms, we employed network pharmacology and molecular docking approaches and confirmed results using in vitro experiments. Biological targets of curcumin and influenza were collected, and potential targets were identified by constructing compound–disease target (C-D) and protein–protein interaction (PPI) networks. The ligand–target interaction was determined using the molecular docking method, and in vitro antiviral experiments and target confirmation were conducted to evaluate curcumin’s effects on influenza. Our network and pathway analyses implicated the four targets of AKT1, RELA, MAPK1, and TP53 that could be involved in the inhibitory effects of curcumin on influenza. The binding energy calculations of each ligand–target interaction in the molecular docking showed that curcumin bound to AKT1 with the highest affinity among the four targets. In vitro experiments, in which influenza virus-infected MDCK cells were pre-, co-, or post-treated with curcumin, confirmed curcumin’s prophylactic and therapeutic effects. Influenza virus induction increased the level of mRNA expression of AKT in MDCK cells, and the level was attenuated by curcumin treatment. Collectively, our findings identified potential targets of curcumin against influenza and suggest curcumin as a potential therapy for influenza infection.

Polyphenols Could Prevent SARS-CoV-2 Infection by Modulating the Expression of miRNAs in the Host Cells

Coronaviruses (CoVs) are single-stranded RNA viruses which following virus attachment and entry into the host cell, particularly type 2 pneumocytes but also endothelial cells, release RNA into cytosol where it serves as a matrix for the host translation machinery to produce viral proteins. The viral RNA in cytoplasm can interact with host cell microRNAs which can degrade viral RNA and/or prevent viral replication. As such host cellular miRNAs represent key cellular mediators of antiviral defense. Polyphenols, plant food bioactives, exert antiviral properties, which is partially due to their capacity to modulate the expression of miRNAs. The objective of this work was to assess if polyphenols can play a role in prevention of SARS-CoV-2 associated complications by modulating the expression of host miRNAs. To test this hypothesis, we performed literature search to identify miRNAs that could bind SARS-CoV-2 RNA as well as miRNAs which expression can be modulated by polyphenols in lung, type 2 pneumocytes or endothelial cells. We identified over 600 miRNAs that have capacity to bind viral RNA and 125 miRNAs which expression can be modulated by polyphenols in the cells of interest. We identified that there are 17 miRNAs with both the capacity to bind viral RNA and which expression can be modulated by polyphenols. Some of these miRNAs have been identified as having antiviral properties or can target genes involved in regulation of processes of viral replication, apoptosis or viral infection. Taken together this analysis suggests that polyphenols could modulate expression of miRNAs in alveolar and endothelial cells and exert antiviral capacity.

Curcumin and Piperine in COVID-19: A Promising Duo to the Rescue?

COVID-19 is now pandemic throughout the world, and scientists are searching for effective therapies to prevent or treat the disease. The combination of curcumin and piperine is a potential option for the management of COVID-19 based on several mechanisms including antiviral, anti-inflammatory, immunomodulatory, antifibrotic, and antioxidant effects. Here, we describe the probable mechanism of curcumin-piperine against COVID-19. Administration of curcumin-piperine combination appears as a potential strategy to counterbalance the pathophysiological features of COVID-19 including inflammation. The optimal dose and duration of curcumin-piperine supplementation should be determined in the future.

Phytochemical Profiles and their Anti-inflammatory Responses Against Influenza from Traditional Chinese Medicine or Herbs

Traditional Chinese medicine (TCM) or herbs are widely used in the prevention and treatment of viral infectious diseases. However, the underlying mechanisms of TCMs remain largely obscure due to complicated material basis and multi-target therapeutics. TCMs have been reported to display anti-influenza activity associated with immunoregulatory mechanisms by enhancing host antiinfluenza immune responses. Previous studies have helped us understand the direct harm caused by the virus itself. In this review, we have tried to summarize recent progress in TCM-based anti-influenza research on the indirect harmful immune responses caused by influenza viruses. In particular, the phytochemicals from TCMs responsible for molecular mechanisms of action belonging to different classes, including phenolic compounds, flavonoids, alkaloids and polysaccharides, have been identified and demonstrated. In addition, this review focuses on the pharmacological mechanism, e.g., inflammatory responses and the interferon (IFN) signaling pathway, which can provide a theoretical basis and approaches for TCM based anti-influenza treatment.

Multifaceted Role of AMPK in Viral Infections

Viral pathogens often exploit host cell regulatory and signaling pathways to ensure an optimal environment for growth and survival. Several studies have suggested that 5'-adenosine monophosphate-activated protein kinase (AMPK), an intracellular serine/threonine kinase, plays a significant role in the modulation of infection. Traditionally, AMPK is a key energy regulator of cell growth and proliferation, host autophagy, stress responses, metabolic reprogramming, mitochondrial homeostasis, fatty acid β-oxidation and host immune function. In this review, we highlight the modulation of host AMPK by various viruses under physiological conditions. These intracellular pathogens trigger metabolic changes altering AMPK signaling activity that then facilitates or inhibits viral replication. Considering the COVID-19 pandemic, understanding the regulation of AMPK signaling following infection can shed light on the development of more effective therapeutic strategies against viral infectious diseases.

Reactive oxygen species as potential antiviral targets

Reactive oxygen species (ROS) are by-products of cellular metabolism and can be either beneficial, at low levels, or deleterious, at high levels, to the cell. It is known that several viral infections can increase oxidative stress, which is mainly facilitated by viral-induced imbalances in the antioxidant defence mechanisms of the cell. While the exact role of ROS in certain viral infections (adenovirus and dengue virus) remains unknown, other viruses can use ROS for enhancement of pathogenesis (SARS coronavirus and rabies virus) or replication (rhinovirus, West Nile virus and vesicular stomatitis virus) or both (hepatitis C virus, human immunodeficiency virus and influenza virus). While several viral proteins (mainly for hepatitis C and human immunodeficiency virus) have been identified to play a role in ROS formation, most mediators of viral ROS modulation are yet to be elucidated. Treatment of viral infections, including hepatitis C virus, human immunodeficiency virus and influenza virus, with ROS inhibitors has shown a decrease in both pathogenesis and viral replication both in vitro and in animal models. Clinical studies indicating the potential for targeting ROS-producing pathways as possible broad-spectrum antiviral targets should be evaluated in randomized controlled trials.

Experimental and clinical reports on anti-inflammatory, antioxidant, and immunomodulatory effects of Curcuma longa and curcumin, an updated and comprehensive review

Curcuma longa (C. longa) or turmeric is a plant with a long history of use in traditional medicine, especially for treating inflammatory conditions C. longa and its main constituent, curcumin (CUR), showed various pharmacological effects such as antioxidant and anti-microbial properties. The updated knowledge of anti-inflammatory, antioxidant, and immunomodulatory effects of C. longa and CUR is provided in this review article. Pharmacological effects of C. longa, and CUR, including anti-inflammatory, antioxidant, and immunomodulatory properties, were searched using various databases and appropriate keywords until September 2020. Various studies showed anti-inflammatory effects of C. longa and CUR, including decreased white blood cell, neutrophil, and eosinophil numbers, and its protective effects on serum levels of inflammatory mediators such as phospholipase A2 and total protein in different inflammatory disorders. The antioxidant effects of C. longa and CUR were also reported in several studies. The plant extracts and CUR decreased malondialdehyde and nitric oxide levels but increased thiol, superoxide dismutase, and catalase levels in oxidative stress conditions. Treatment with C. longa and CUR also improved immunoglobulin E (Ig)E, pro-inflammatory cytokine interleukin 4 (IL)-4, transforming growth factor-beta, IL-17, interferon-gamma levels, and type 1/type 2 helper cells (Th1)/(Th2) ratio in conditions with disturbance in the immune system. Therefore C. longa and CUR showed anti-inflammatory, antioxidant, and immunomodulatory effects, indicating a potential therapeutic effect of the plant and its constituent, CUR, for treating of inflammatory, oxidative, and immune dysregulation disorders.

Spices and herbs: Potential antiviral preventives and immunity boosters during COVID-19

A severe acute respiratory syndrome is an unusual type of contagious pneumonia that is caused by SARS coronavirus. At present, the whole world is trying to combat this coronavirus disease and scientific communities are putting rigorous efforts to develop vaccines. However, there are only a few specific medical treatments for SARS-CoV-2. Apart from other public health measures taken to prevent this virus, we can boost our immunity with natural products. In this article, we have highlighted the potential of common spices and herbs as antiviral agents and immunity boosters. A questionnaire-based online survey has been conducted on home remedies during COVID-19 among a wide range of peoples (n-531) of different age groups (13-68 years) from various countries. According to the survey, 71.8% of people are taking kadha for combating infection and boosting immunity. Most people (86.1%) think that there is no side effect of kadha while 13.9% think vice versa. A total of 93.6% of people think that spices are helpful in curing coronavirus or other viral infection as well as boosting immunity. Most people are using tulsi drops, vitamin C, and chyawanprash for boosting their immunity. Therefore, we conclude from the survey and available literature that spices and herbs play a significant role against viral infections.

Potential bioactive compounds of medicinal plants against new Coronavirus (SARS-CoV-2): A review

Nowadays, COVID-19 cases are growing worldwide, and there is no evidence of an effective drug to combat the new SARS-CoV-2 virus. In this sense, medicinal plants as an alternative treatment are being used without control to handle the pandemic situation. Therefore, bioactive compounds against Coronavirus of medicinal plant species that grow in Ecuador are discussed. The plant species described in this review are Azadirachta indica, Cinchona pubescens, Coriandrum sativum, Cúrcuma longa, Eucalyptus spp, Morus alba, and Salvia rosmarinus[A3] ; and compunds are curcumin, coriandrin, deoxynojirimycin, kuwanon G, mulberroside A, oleanolic acid, rosmarinic acid, ursolic acid, quinine, eucalyptol, and jensenone.

Comparation of Anti-Inflammatory and Antioxidantactivities of Curcumin, Tetrahydrocurcuminand Octahydrocurcuminin LPS-Stimulated RAW264.7 Macrophages

Curcumin (CUR) possesses pronounced anti-inflammatory and antioxidant activities. Generally, the clinical application of CUR is restricted due to its apparent unstability and poor absorption, and the biological activities of CUR may be closely associated with its metabolites. Tetrahydrocurcumin (THC) and octahydrocurcumin (OHC) are two major hydrogenated metabolites of CUR with appreciable biological potentials. Here, we comparatively explored the anti-inflammatory and antioxidant activities of CUR, THC, and OHC in lipopolysaccharide- (LPS-) induced RAW264.7 macrophages. The results revealed that CUR, THC, and OHC dose-dependently inhibited the generation of NO and MCP-1 as well as the gene expression of MCP-1 and iNOS. Additionally, CUR, THC, and OHC significantly inhibited NF-κB activation and p38MAPK and ERK phosphorylation, while substantially upregulated the Nrf2 target gene expression (HO-1, NQO-1, GCLC, and GCLM). Nevertheless, zinc protoporphyrin (ZnPP), a typical HO-1 inhibitor, significantly reversed the alleviative effect of CUR, THC, and OHC on LPS-stimulated ROS generation. These results demonstrated that CUR, THC, and OHC exerted beneficial effect on LPS-stimulated inflammatory and oxidative responses, at least partially, through inhibiting the NF-κB and MAPKs pathways and activating Nrf2-regulated antioxidant gene expression. Particularly, THC and OHC might exert superior antioxidant and anti-inflammatory activities to CUR in LPS-stimulated RAW264.7 cells, which can be further explored to be a promising novel effective agent for inflammatory treatment.

Virtual screening of curcumin and its analogs against the spike surface glycoprotein of SARS-CoV-2 and SARS-CoV

COVID-19, a new pandemic caused by SARS-CoV-2, was first identified in 2019 in Wuhan, China. The novel corona virus SARS-CoV-2 and the 2002 SARS-CoV have 74% identity and use similar mechanisms to gain entry into the cell. Both the viruses enter the host cell by binding of the viral spike glycoprotein to the host receptor, angiotensin converting enzyme 2 (ACE2). Targeting entry of the virus has a better advantage than inhibiting the later stages of the viral life cycle. The crystal structure of the SARS-CoV (6CRV: full length S protein) and SARS-CoV-2 Spike proteins (6M0J: Receptor binding domain, RBD) was used to determine potential small molecule inhibitors. Curcumin, a naturally occurring phytochemical in Curcuma longa, is known to have broad pharmacological properties. In the present study, curcumin and its derivatives were docked, using Autodock 4.2, onto the 6CRV and 6M0J to study their capability to act as inhibitors of the spike protein and thereby, viral entry. The curcumin and its derivatives displayed binding energies, ΔG, ranging from −10.98 to −5.12 kcal/mol (6CRV) and −10.01 to −5.33 kcal/mol (6M0J). The least binding energy was seen in bis-demethoxycurcumin with: ΔG = −10.98 kcal/mol (6CRV) and −10.01 kcal/mol (6M0J). A good binding energy, drug likeness and efficient pharmacokinetic parameters suggest the potential of curcumin and few of its derivatives as SARS-CoV-2 spike protein inhibitors. However, further research is necessary to investigate the ability of these compounds as viral entry inhibitors.

Communicated by Ramaswamy H. Sarma

Footprint of the COVID-19 Pandemic in India: A Study of Immune Landscape and Other Factors Shielding Mortality

The impact of the SARS-CoV-2 pandemic has significantly affected global health and created a world crisis. The exponentially increasing numbers of infection and mortality have made preventive measures challenging. India being a highly populated nation has so far effectively counteracted the pandemic outbreak with a significantly lower rate of mortality despite the high infection rates. The genetic architecture of the immune response genes in the Indian population, BCG vaccination, the predominantly young age group of people, and their traditional food habits might contribute to the lower rate of mortality. Human leukocyte antigens (HLA) play a vital role in triggering T cells, and natural killer (NK) cells can immediately react to eliminate infected cells. Activation of virus-specific CD4+ T cells and CD8+ cytotoxic T cells selectively targets the infected cells and strengthens the immunoregulatory system. The checkpoint for NK cell function is the engagement of killer Ig-like receptors (KIR) molecules with their respective HLA ligands overexpressed or expressed on the compromised virus-infected cells which have shown polymorphism among different ethnic groups. Here, we explore if certain KIR-HLA motifs grant Indians a survival advantage in terms of the low rate of mortality. Additionally, enhanced immunity through BCG vaccination may favor fruitful eradication of SARS-CoV-2 and provide the way out as in therapeutic intervention and vaccination strategies.

EGYVIR: An immunomodulatory herbal extract with potent antiviral activity against SARS-CoV-2

Due to the challenges for developing vaccines in devastating pandemic situations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), developing and screening of novel antiviral agents are peremptorily demanded. Herein, we developed EGYVIR as a potent immunomodulatory herbal extract with promising antiviral activity against SARS-CoV-2. It constitutes of a combination of black pepper extract with curcumin extract. The antiviral effect of EGYVIR extract is attributed to the two key phases of the disease in severe cases. First, the inhibition of the nuclear translocation of NF-kβ p50, attenuating the SARS-CoV-2 infection-associated cytokine storm. Additionally, the EGYVIR extract has an in vitro virucidal effect for SARS-CoV-2. The in vitro study of EGYVIR extract against SARS-CoV-2 on Huh-7 cell lines, revealed the potential role of NF-kβ/TNFα/IL-6 during the infection process. EGYVIR antagonizes the NF-kβ pathway in-silico and in-vitro studies. Consequently, it has the potential to hinder the release of IL-6 and TNFα, decreasing the production of essential cytokines storm elements.

Evaluation of the effect of curcumin on pneumonia: A systematic review of preclinical studies

Pneumonia is a major cause of morbidity and mortality worldwide and causes a significant burden on the healthcare systems. Curcumin is a natural phytochemical with anti-inflammatory and anti-neoplastic characteristics. The aim of this study was to conduct a systematic review of published studies on the effect of curcumin on preclinical models of pneumonia. A comprehensive search was conducted in PubMed/Medline, Scopus, Web of Science and Google Scholar from inception up to March 1, 2020 to recognize experimental or clinical trials assessing the effects of curcumin on pneumonia. We identified 17 primary citations that evaluated the effects of curcumin on pneumonia. Ten (58.8%) studies evaluated the effect of curcumin on mouse models of pneumonia, generated by intranasal inoculation of viruses or bacteria. Seven (41.2%) studies evaluated the inhibitory effects of curcumin on the pneumonia-inducing bacteria. Our results demonstrated that curcumin ameliorated the pneumonia-induced lung injury, mainly through a reduction of the activity and infiltration of neutrophils and the inhibition of inflammatory response in mouse models. Curcumin ameliorates the severity of pneumonia through a reduction in neutrophil infiltration and by amelioration of the exaggerated immune response in preclinical pneumonia models.

Curcumin as an Antiviral Agent

Curcumin, the primary curcuminoid compound found in turmeric spice, has shown broad activity as an antimicrobial agent, limiting the replication of many different fungi, bacteria and viruses. In this review, we summarize recent studies supporting the development of curcumin and its derivatives as broad-spectrum antiviral agents.

The Inhibitory Effect of Curcumin on Virus-Induced Cytokine Storm and Its Potential Use in the Associated Severe Pneumonia

Coronavirus infection, including SARS-CoV, MERS-CoV, and SARS-CoV2, causes daunting diseases that can be fatal because of lung failure and systemic cytokine storm. The development of coronavirus-evoked pneumonia is associated with excessive inflammatory responses in the lung, known as "cytokine storms," which results in pulmonary edema, atelectasis, and acute lung injury (ALI) or fatal acute respiratory distress syndrome (ARDS). No drugs are available to suppress overly immune response-mediated lung injury effectively. In light of the low toxicity and its antioxidant, anti-inflammatory, and antiviral activity, it is plausible to speculate that curcumin could be used as a therapeutic drug for viral pneumonia and ALI/ARDS. Therefore, in this review, we summarize the mounting evidence obtained from preclinical studies using animal models of lethal pneumonia where curcumin exerts protective effects by regulating the expression of both pro- and anti-inflammatory factors such as IL-6, IL-8, IL-10, and COX-2, promoting the apoptosis of PMN cells, and scavenging the reactive oxygen species (ROS), which exacerbates the inflammatory response. These studies provide a rationale that curcumin can be used as a therapeutic agent against pneumonia and ALI/ARDS in humans resulting from coronaviral infection.

Potential Role of Nrf2 Activators with Dual Antiviral and Anti-Inflammatory Properties in the Management of Viral Pneumonia

The outbreak of coronavirus disease 2019 (COVID-19) pandemic has already caused a huge burden to the global healthcare system, with the death toll reached tens of thousands. Although some antiviral agents were identified and used to inhibit viral replication, the management of cytokine storm is also a critical issue. In this article, we reviewed the literature on drug candidates for severe acute respiratory syndrome (SARS-CoV-1) and provided a brief overview of a class of drugs that exert antiviral and anti-inflammatory effects. These molecules mitigated inflammatory cytokine cascades induced by viral infections via Nrf2 activating capacity and might have additional anti-fibrotic and anti-remodeling properties. Besides, their effects on the regulation of scavenger receptors expression by macrophages may offer some benefits to the pulmonary antibacterial defense system after viral infection. The potential roles of these agents assessed on the basis of the pathophysiology of viral pneumonia and acute respiratory distress syndrome were also discussed. Further research is needed to ascertain whether Nrf2 activators are useful in the management of viral pneumonia.

Redox-Modulating Agents in the Treatment of Viral Infections

Viruses use cell machinery to replicate their genome and produce viral proteins. For this reason, several intracellular factors, including the redox state, might directly or indirectly affect the progression and outcome of viral infection. In physiological conditions, the redox balance between oxidant and antioxidant species is maintained by enzymatic and non-enzymatic systems, and it finely regulates several cell functions. Different viruses break this equilibrium and induce an oxidative stress that in turn facilitates specific steps of the virus lifecycle and activates an inflammatory response. In this context, many studies highlighted the importance of redox-sensitive pathways as novel cell-based targets for therapies aimed at blocking both viral replication and virus-induced inflammation. In the review, we discuss the most recent findings in this field. In particular, we describe the effects of natural or synthetic redox-modulating molecules in inhibiting DNA or RNA virus replication as well as inflammatory pathways. The importance of the antioxidant transcription factor Nrf2 is also discussed. Most of the data reported here are on influenza virus infection. We believe that this approach could be usefully applied to fight other acute respiratory viral infections characterized by a strong inflammatory response, like COVID-19.

The antiviral and coronavirus-host protein pathways inhibiting properties of herbs and natural compounds - Additional weapons in the fight against the COVID-19 pandemic?

Introduction

As of March 11th, 2020, the World Health Organization declared the COVID-19 outbreak a pandemic. Articles published after the SARS-CoV-1 (2002) epidemic suggest that the use of an herbal-drug integrative medical approach could have contributed to a lower fatality rate and a more rapid response in controlling the outbreak.

Methods

Pubmed was searched for articles that investigated the antiviral properties and mechanisms of action of herbs or natural compounds against the SARS-coronavirus (CoV).

Results

Forty-three (43) relevant papers were located. A general count rendered 450+ herbs and natural compounds with antiviral properties against the SARS-CoV and related viruses. From the 43 articles, thirty-one (31) uncovered the mechanisms of action of the natural substances able to oppose the coronavirus.

Discussion

A series of herbs and natural compounds demonstrated moderate to strong antiviral activity. Research on many herbs-natural compounds also showed potent and significant inhibition of CoV-host protein pathways responsible for different phases of viral replication specifically targeting 3CL^PRO, PL^PRO, RdRp, helicase protein, S protein, N protein, 3a protein, Cathepsin L, Nsp1, Nsp3c, and ORF7a, and the S protein/ACE-2 interaction.

Conclusion

The herbs-natural compounds with antiviral activity and that caused inhibition/blockade of the CoV-host protein pathways are potential therapeutic candidates. The homology between the SARS-CoV-1 and SARS-CoV-2 is around 80%. Thus, effective herbs-compounds for the former would likely be beneficial for the latter also depending on target protein similarities between the viruses. Here we provide the mechanistic bases supporting an integrative approach that includes natural compounds to fight coronavirus infections.

Biochemistry, Safety, Pharmacological Activities, and Clinical Applications of Turmeric: A Mechanistic Review

Turmeric (Curcuma longa L.) is a popular natural drug, traditionally used for the treatment of a wide range of diseases. Its root, as its most popular part used for medicinal purposes, contains different types of phytochemicals and minerals. This review summarizes what is currently known on biochemistry, safety, pharmacological activities (mechanistically), and clinical applications of turmeric. In short, curcumin is considered as the fundamental constituent in ground turmeric rhizome. Turmeric possesses several biological activities including anti-inflammatory, antioxidant, anticancer, antimutagenic, antimicrobial, antiobesity, hypolipidemic, cardioprotective, and neuroprotective effects. These reported pharmacologic activities make turmeric an important option for further clinical research. Also, there is a discussion on its safety and toxicity.

The prognostic impact of traditional Chinese medicine monomers on tumor-associated macrophages in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for 80%-85% of all lung malignancies and good diagnosis and prognosis of NSCLC are critical to the increase of its survival rate. Tumor-associated macrophages (TAM) abundantly present in numerous cancer types, and the role of TAMs in tumor biology and their prognostic value in cancer become major topics of interest. After various stimulations in the tumor microenvironment, TAMs develop into a M1 (tumor-inhibitory) phenotype or M2 (tumor-promoting) phenotype. Recent studies show that traditional Chinese medicine (TCM) monomers have markedly inhibitory actions for NSCLC through M1/M2 modulation. Due to the TCM monomers mainly covered five categories, i.e. terpenoids, flavonoids, polysaccharides, natural polyphenols, and alkaloids. Thus, we will discuss the regulation of TCM monomers on TAM involve in these five parts in this review. In addition, the potential role of TAMs as therapeutic targets will be discussed.

Study on the Mechanism of Curcumin Regulating Lung Injury Induced by Outdoor Fine Particulate Matter (PM2.5)

Background

Epidemiological studies have shown that exposure to PM induces oxidative stress, leading to a variety of health problems. In particular, PM2.5 contains a lot of substances harmful to the human body and penetrates into the lungs to induce lung injury. At the same time, there is increasing evidence that oxidative stress also affects the severity of lung injury. However, there is still no good way to reduce or eliminate these hazards. In the future, more experimental research is needed to further confirm the mechanisms of these hazards and formulate effective preventive measures and treatment plans for their hazard mechanisms. Curcumin has been reported to reduce oxidative stress and inflammatory damage and protect organs.

Objective

To investigate whether curcumin can play a protective role against PM2.5-induced oxidative stress and inflammatory damage by inducing expression of the HO-1/CO/P38 MAPK pathway.

Methods

In this experiment, PM2.5 was dropped into the trachea to establish a lung injury model in mice. 28 SPF-grade male Kunming mice were randomly divided into 4 groups: normal control group, saline control group, PM2.5 treatment group, and curcumin intervention group. Albumin (ALB), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) were measured in alveolar lavage fluid (BALF) to assess lung tissue damage. Colorimetric detection of oxidative stress indicators such as MDA, GSH-PX, T-AOC, and CAT in the lung tissue was performed. The levels of IL-6 and TNF-α in the lung tissue were determined by ELISA. Histopathological examination was used for the assessment of alveolar epithelial damage. The protein expression of the HO-1/P38 MAPK pathway in the lung tissue was determined by Western blot and immunohistochemistry. Endogenous CO was detected by spectrophotometry. The results showed that the expression of the HO-1/CO/P38 MAPK protein in the lung tissue was significantly increased in the curcumin intervention group compared with the PM2.5 treatment group, and it was statistically significant (P < 0.05). Compared with the PM2.5 treatment group, the curcumin intervention group can reduce the amount of ALB, LDH, and ALP in BALF; reduce the levels of MDA, IL-1, and TNF-α in the lung tissue; and improve GSH-PX, T-AOC, and CAT levels, but there is no statistical difference (P > 0.05).

Conclusion

We found that PM2.5 can cause lung damage through oxidative stress and inflammatory responses. Oxidative stress and inflammatory responses increase the expression of HO-1/CO/P38 MAPK. The intervention of curcumin can further increase the expression of HO-1/CO/P38 MAPK.

Curcumin and Heme Oxygenase: Neuroprotection and Beyond

Curcumin is a natural polyphenol component of Curcuma longa Linn, which is currently considered one of the most effective nutritional antioxidants for counteracting free radical-related diseases. Several experimental data have highlighted the pleiotropic neuroprotective effects of curcumin, due to its activity in multiple antioxidant and anti-inflammatory pathways involved in neurodegeneration. Although its poor systemic bioavailability after oral administration and low plasma concentrations represent restrictive factors for curcumin therapeutic efficacy, innovative delivery formulations have been developed in order to overwhelm these limitations. This review provides a summary of the main findings involving the heme oxygenase/biliverdin reductase system as a valid target in mediating the potential neuroprotective properties of curcumin. Furthermore, pharmacokinetic properties and concerns about curcumin's safety profile have been addressed.