Nanocurcumin improves Treg cell responses in patients with mild and severe SARS-CoV2

COVID-19-Associated Sepsis: Potential Role of Phytochemicals as Functional Foods and Nutraceuticals

The acute manifestations of coronavirus disease 2019 (COVID-19) exhibit the hallmarks of sepsis-associated complications that reflect multiple organ failure. The inflammatory cytokine storm accompanied by an imbalance in the pro-inflammatory and anti-inflammatory host response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection leads to severe and critical septic shock. The sepsis signature in severely afflicted COVID-19 patients includes cellular reprogramming and organ dysfunction that leads to high mortality rates, emphasizing the importance of improved clinical care and advanced therapeutic interventions for sepsis associated with COVID-19. Phytochemicals of functional foods and nutraceutical importance have an incredible impact on the healthcare system, which includes the prevention and/or treatment of chronic diseases. Hence, in the present review, we aim to explore the pathogenesis of sepsis associated with COVID-19 that disrupts the physiological homeostasis of the body, resulting in severe organ damage. Furthermore, we have summarized the diverse pharmacological properties of some potent phytochemicals, which can be used as functional foods as well as nutraceuticals against sepsis-associated complications of SARS-CoV-2 infection. The phytochemicals explored in this article include quercetin, curcumin, luteolin, apigenin, resveratrol, and naringenin, which are the major phytoconstituents of our daily food intake. We have compiled the findings from various studies, including clinical trials in humans, to explore more into the therapeutic potential of each phytochemical against sepsis and COVID-19, which highlights their possible importance in sepsis-associated COVID-19 pathogenesis. We conclude that our review will open a new research avenue for exploring phytochemical-derived therapeutic agents for preventing or treating the life-threatening complications of sepsis associated with COVID-19.

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.

Role of dietary supplements in the continuous battle against COVID-19

A sudden outbreak of the COVID-19 pandemic was a big blow to the world community on every level. Created by a novel coronavirus, SARS-CoV-2, which was previously unknown to the human immune system. The expert opinion almost immediately united on the fact that the most effective way of fighting the pandemic would be by building immunity artificially via a mass immunization program. However, it took about a year for the approval of the first vaccine against COVID-19. In the meantime, a big part of the general population started adapting nutritious diet plans and dietary supplements to boost natural immunity as a potential prophylactic strategy against SARS-CoV-2 infection. Whether they originate from mainstream medicine, such as synthetic supplements, or traditional herbal remedies in the form of single or poly-herbs, these supplements may comprise various components that exhibit immunomodulatory, anti-inflammatory, antioxidant, and antimicrobial characteristics. There is a substantial body of predictions and expert opinions suggesting that enhancing one's diet with dietary supplements containing additional nutrients and bioactive compounds like vitamins, minerals, amino acids, fatty acids, phytochemicals, and probiotics can enhance the immune system's ability to develop resistance against COVID-19, although none of them have any conclusive evidence nor officially recommended by World Health Organization (WHO). The current review critically acclaims the gap between public perception-based preference and real evidence-based study to weigh the actual benefit of dietary supplements in relation to COVID-19 prevention and management.

Immunoregulatory effects of nanocurcumin in inflammatory milieu: Focus on COVID-19

The use of natural compounds, such as curcumin, to treat infections caused by bacteria, viruses, fungi, parasites, inflammatory diseases, and various types of cancer is an active and dynamic area of research. Curcumin has a long history of use in the food industry, and there is currently a growing interest in its therapeutic applications. Numerous clinical trials have consistently shown that curcumin, a polyphenolic compound, is safe and well-tolerated even at high doses. There is no toxicity limit. However, the clinical efficacy of curcumin has been limited by its constraints. However, scientific evidence indicates that the use of adjuvants and carriers, such as nanoparticles, exosomes, micelles, and liposomes, can help overcome this limitation. The properties, functions, and human benefits of using nanocurcumin are well-supported by scientific research. Recent evidence suggests that nanocurcumin may be a beneficial therapeutic modality due to its potential to decrease gene expression and secretion of specific inflammatory biomarkers involved in the cytokinestorm seen in severe COVID-19, as well as increase lymphocyte counts. Nanocurcumin has demonstrated the ability to improve clinical manifestations and modulate immune response and inflammation in various autoinflammatory diseases. Additionally, its efficacy, affordability, and safety make it a promising replacement for residual cancer cells after tumor removal. However, further studies are necessary to evaluate the safety and efficacy of nanocurcumin as a new therapeutic in clinical trials, including appropriate dosage, frequency, and duration.

Plant-Derived Polyphenols to Prevent and Treat Oral Mucositis Induced by Chemo- and Radiotherapy in Head and Neck Cancers Management

Oral Mucositis (OM) is the most common side effect due to chemotherapy and radiotherapy, which are the conventional treatment options for head and neck cancers. OM is a severe inflammatory condition characterized by multifactorial etiopathogenesis. It further negatively affects patients' quality of life by severe impairment of normal oral functions. Consequently, it is mandatory to identify new effective therapeutic approaches to both prevent and treat OM while also avoiding any recurrence. Polyphenols recently attracted the interest of the scientific community due to their low toxicity and wide range of biological activities making them ideal candidates for several applications in the odontostomatological field, particularly against OM. This review collects the in vivo studies and the clinical trials conducted over the past 13 years evaluating the preventive and curative effects of several polyphenolic compounds towards chemo- and radiotherapy-induced OM, both when administered alone or as a plant-extracted phytocomplex. The literature fully confirms the usefulness of these molecules, thus opening the possibility of their clinical application. However, polyphenol limitations (e.g., unfavourable physicochemical properties and susceptibility to degradation) have emerged. Consequently, the interest of the scientific community should be focused on developing innovative delivery systems able to stabilize polyphenols, thus facilitating topical administration and maximizing their efficacy.

Curcumin as an antiviral agent and immune-inflammatory modulator in COVID-19: A scientometric analysis

Background

Reports regarding the antiviral activity of curcumin have surfaced. However, to date there has been no scientometric analysis of the relationship between curcumin and Coronavirus Disease 2019 (COVID-19). To comprehensively understand the studies involving curcumin in the context of COVID-19, we conducted a scientometric analysis to provide an exhaustive review of these studies.

Methods

We systematically searched the Web of Science core collection database for bibliographic data indexed from January 1, 2020, to December 31, 2022, using keywords such as 'curcumin', 'COVID-19', and their synonyms. To clarify the research content and trends related to curcumin in COVID-19, we utilized VOSviewer, Origin 2023, and Charticulator for analysis, supplemented by external data.

Results

The final count of publications included in this study was 252. These publications originated from 63 countries or territories, with India contributing the highest number of publications. They were published across 170 journals. Notably, the Egyptian Knowledge Bank (EKB) emerged as the most important institution that carried out this study. The most cited publication had been referenced 166 times. The main elements involved in the keyword analysis were reflected in the antiviral activity of curcumin and the immuno-inflammatory modulation of the inflammatory cytokine storm. Furthermore, the pharmacological mechanisms of curcumin for treating COVID-19 emerged as a prominent area of research. Simultaneously, there exists direct evidence of clinical usage of curcumin to enhance COVID-19 outcomes.

Conclusions

The scientometric analysis underscores the burgeoning professional domain of curcumin-based treatment for COVID-19. Ongoing studies have focused on the antiviral activity of curcumin and its immunomodulatory effects on inflammatory cytokine storms. On the other hand, the pharmacological mechanism of curcumin in the treatment of COVID-19 is a hot spot in the research field at present, which may become the main research trend in this field in the future. While maintaining a focus on foundational research, the clinical application of curcumin in COVID-19 infection is developing in parallel, highlighting its obvious guiding value in clinical practice. These insights offer researchers a snapshot of the present state of curcumin treatment for COVID-19 and guide further mechanistic validation efforts in the future.

Combining nano-curcumin with catechin improves COVID-19-infected patient's inflammatory conditions

AIMS

A hyperinflammatory condition is brought on by the development of Coronavirus disease 2019 (COVID-19), which is characterized by an elevation of T helper (Th) 17 cells, high levels of pro-inflammatory cytokines, and a depletion of regulatory T (Treg) cells.

METHODS

In this research, we examined the effect of nano-curcumin and catechin on the TCD4+, TCD8+, Th17, and Treg cells and their associated factors in COVID-19 patients. For this purpose, 160 (50 patients excluded during the study) COVID-19 patients were divided into four groups: placebo, nano-curcumin, catechin, and nano-curcumin + catechin. The frequency of TCD4+, TCD8+, Th17, and Treg cells, the gene expression of transcription factors (STAT3, RORt, and FoxP3) relevant to Th17 and Treg, as well as the serum levels of cytokines (IL-6, IL17, IL1-b, IL-10, and TGF-), were all evaluated intra- and inter-group, before and after treatment, in all groups.

RESULTS

Our study showed that TCD4 + and TCD8 + cells were significantly higher in the nano-curcumin + catechin group compared to the control group, whereas Th17 was lower than the initial value. Furthermore, compared to the placebo-received group, cytokines and transcription factors associated with Th17 were significantly lower in the nano-curcumin + catechin group. Additionally, combined therapy increased Treg cells and transcription factors compared to the placebo group.

CONCLUSION

Overall, our results show that combining nano-curcumin with catechin has a more notable impact on the enhancement of TCD4+, TCD8+, and Treg cells, as well as a decrease in Th17 cells and their mediators, suggesting a promising combination therapy in reducing the inflammatory conditions of COVID-19 infected patients.

Applications of Curcumin and Its Nanoforms in the Treatment of Cancer

Due to the diverse medicinal and pharmacokinetic properties of turmeric, it is well-known in the therapeutic, pharmaceutic, nutraceutical, cosmetic, and dietary industries. It gained importance due to its multitude of properties, such as wound-healing, anti-inflammatory, anti-oxidant, anti-microbial, cytoprotective, anti-aging, anti-cancer, and immunomodulatory effects. Even though the natural healing effect of turmeric has been known to Indians as early as 2500 BCE, the global demand for turmeric has increased only recently. A major reason for the beneficiary activities of turmeric is the presence of the yellow-colored polyphenolic compound called curcumin. Many studies have been carried out on the various properties of curcumin and its derivatives. Despite its low bioavailability, curcumin has been effectively used for the treatment of many diseases, such as cardiovascular and neurological diseases, diabetes, arthritis, and cancer. The advent of nanobiotechnology has further opened wide opportunities to explore and expand the use of curcumin in the medical field. Nanoformulations using curcumin and its derivatives helped to design new treatment modalities, specifically in cancer, because of the better bioavailability and solubility of nanocurcumin when compared to natural curcumin. This review deals with the various applications of curcumin nanoparticles in cancer therapy and broadly tries to understand how it affect the immunological status of the cancer cell.

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).

Role of Turmeric and Curcumin in Prevention and Treatment of Chronic Diseases: Lessons Learned from Clinical Trials

Turmeric (Curcuma longa) has been used for thousands of years for the prevention and treatment of various chronic diseases. Curcumin is just one of >200 ingredients in turmeric. Almost 7000 scientific papers on turmeric and almost 20,000 on curcumin have been published in PubMed. Scientific reports based on cell culture or animal studies are often not reproducible in humans. Therefore, human clinical trials are the best indicators for the prevention and treatment of a disease using a given agent/drug. Herein, we conducted an extensive literature survey on PubMed and Scopus following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The keywords "turmeric and clinical trials" and "curcumin and clinical trials" were considered for data mining. A total of 148 references were found to be relevant for the key term "turmeric and clinical trials", of which 70 were common in both PubMed and Scopus, 44 were unique to PubMed, and 34 were unique to Scopus. Similarly, for the search term "curcumin and clinical trials", 440 references were found to be relevant, of which 70 were unique to PubMed, 110 were unique to Scopus, and 260 were common to both databases. These studies show that the golden spice has enormous health and medicinal benefits for humans. This Review will extract and summarize the lessons learned about turmeric and curcumin in the prevention and treatment of chronic diseases based on clinical trials.

Antioxidant and anti-inflammatory effects of curcumin/turmeric supplementation in adults: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

Turmeric and its prominent bioactive compound, curcumin, have been the subject of many investigations with regard to their impact on inflammatory and oxidative balance in the body. In this systematic review and meta-analysis, we summarized the existing literature on randomized controlled trials (RCTs) which examined this hypothesis. Major databases (PubMed, Scopus, Web of Science, Cochrane Library and Google Scholar) were searched from inception up to October 2022. Relevant studies meeting our eligibility criteria were obtained. Main outcomes included inflammatory markers (i.e. C-reactive protein(CRP), tumour necrosis factorα(TNF-α), interleukin-6(IL-6), and interleukin 1 beta(IL-1β)) and markers of oxidative stress (i.e. total antioxidant capacity (TAC), malondialdehyde(MDA), and superoxide dismutase (SOD) activity). Weighted mean differences (WMDs) were reported. P-values < 0.05 were considered significant. Sixty-six RCTs were included in the final analysis. We observed that turmeric/curcumin supplementation significantly reduces levels of inflammatory markers, including CRP (WMD: -0.58 mg/l, 95 % CI: -0.74, -0.41), TNF-α (WMD: -3.48 pg/ml, 95 % CI: -4.38, -2.58), and IL-6 (WMD: -1.31 pg/ml, 95 % CI: -1.58, -0.67); except for IL-1β (WMD: -0.46 pg/ml, 95 % CI: -1.18, 0.27) for which no significant change was found. Also, turmeric/curcumin supplementation significantly improved anti-oxidant activity through enhancing TAC (WMD = 0.21 mmol/l; 95 % CI: 0.08, 0.33), reducing MDA levels (WMD = -0.33 µmol /l; 95 % CI: -0.53, -0.12), and SOD activity (WMD = 20.51 u/l; 95 % CI: 7.35, 33.67). It seems that turmeric/curcumin supplementation might be used as a viable intervention for improving inflammatory/oxidative status of individuals.

Curcumin Formulations for Better Bioavailability: What We Learned from Clinical Trials Thus Far?

Curcumin has been credited with a wide spectrum of pharmacological properties for the prevention and treatment of several chronic diseases such as arthritis, autoimmune diseases, cancer, cardiovascular diseases, diabetes, hemoglobinopathies, hypertension, infectious diseases, inflammation, metabolic syndrome, neurological diseases, obesity, and skin diseases. However, due to its weak solubility and bioavailability, it has limited potential as an oral medication. Numerous factors including low water solubility, poor intestinal permeability, instability at alkaline pH, and fast metabolism contribute to curcumin's limited oral bioavailability. In order to improve its oral bioavailability, different formulation techniques such as coadministration with piperine, incorporation into micelles, micro/nanoemulsions, nanoparticles, liposomes, solid dispersions, spray drying, and noncovalent complex formation with galactomannosides have been investigated with in vitro cell culture models, in vivo animal models, and humans. In the current study, we extensively reviewed clinical trials on various generations of curcumin formulations and their safety and efficacy in the treatment of many diseases. We also summarized the dose, duration, and mechanism of action of these formulations. We have also critically reviewed the advantages and limitations of each of these formulations compared to various placebo and/or available standard care therapies for these ailments. The highlighted integrative concept embodied in the development of next-generation formulations helps to minimize bioavailability and safety issues with least or no adverse side effects and the provisional new dimensions presented in this direction may add value in the prevention and cure of complex chronic diseases.

Curcumin for the treatment of COVID-19 patients: A meta-analysis of randomized controlled trials

Curcumin is a low-cost and easily accessible therapeutic option for COVID-19 patients. We aimed to conduct a meta-analysis to assess the effect of curcumin on clinical outcomes in COVID-19 patients. Various databases, including PubMed, the Cochrane Library and Embase were searched from inception until October 2022 for randomized controlled trials (RCTs) evaluating curcumin use in COVID-19 patients. Results from 13 RCTs were pooled using R software version 4.1.0. Curcumin reduced the risk of all-cause mortality (RR 0.38; 95% CI: 0.20-0.72; moderate certainty of evidence), and patients with no recovery status (RR 0.54; 95% CI: 0.42-0.70; moderate certainty of evidence) but had no effect on the incidence of mechanical ventilation and hospitalization, and the rate of a positive viral PCR test. The results of subgroup analysis suggested a higher benefit with early administration of curcumin (within 5 days of onset of symptoms) and with the use of combination regimens. Curcumin is likely to be of benefit in mild-to-moderate COVID-19 patients, but large-scale RCTs are needed to confirm these findings. The limitations of our meta-analysis include the small sample sizes of the included RCTs and the variable formulations of curcumin used across the studies.

Immune responses in mildly versus critically ill COVID-19 patients

The current coronavirus pandemic (COVID-19), caused by SARS-CoV-2, has had devastating effects on the global health and economic system. The cellular and molecular mediators of both the innate and adaptive immune systems are critical in controlling SARS-CoV-2 infections. However, dysregulated inflammatory responses and imbalanced adaptive immunity may contribute to tissue destruction and pathogenesis of the disease. Important mechanisms in severe forms of COVID-19 include overproduction of inflammatory cytokines, impairment of type I IFN response, overactivation of neutrophils and macrophages, decreased frequencies of DC cells, NK cells and ILCs, complement activation, lymphopenia, Th1 and Treg hypoactivation, Th2 and Th17 hyperactivation, as well as decreased clonal diversity and dysregulated B lymphocyte function. Given the relationship between disease severity and an imbalanced immune system, scientists have been led to manipulate the immune system as a therapeutic approach. For example, anti-cytokine, cell, and IVIG therapies have received attention in the treatment of severe COVID-19. In this review, the role of immunity in the development and progression of COVID-19 is discussed, focusing on molecular and cellular aspects of the immune system in mild vs. severe forms of the disease. Moreover, some immune- based therapeutic approaches to COVID-19 are being investigated. Understanding key processes involved in the disease progression is critical in developing therapeutic agents and optimizing related strategies.

The possible therapeutic role of curcumin and quercetin in the early-stage of COVID-19-Results from a pragmatic randomized clinical trial

Background

Curcumin (CUR) and quercetin (QUE), two natural polyphenols, possess diverse biological activities including broad-spectrum antiviral, antioxidant, and immunomodulatory effects. Both CUR and QUE have shown inhibition of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in in vitro assays.

Objective

In the present study we aimed to assess the possible treatment benefits of a combined curcumin and quercetin (CUR-QUE) oral supplement, alongside standard of care (SOC), in the early-stage COVID-19 infection.

Methods

This was an exploratory, pragmatic, open-label, randomized controlled clinical trial, conducted at the Department of Pathology, Liaquat University of Medical and Health Sciences, Jamshoro, PK. The study compared the treatment effect of an oral CUR-QUE supplement plus SOC vs. SOC alone, in the early-stage/mild to moderately symptomatic COVID-19 outpatients. Patients were randomized in a 1:1 ratio to CUR-QUE (n = 25) and control (n = 25) treatment groups. The CUR-QUE supplementation consisted of a daily intake of 168 mg curcumin and 260 mg quercetin, as two soft capsules, to be taken twice a day at home for 14 days.

Results

After one-week of treatment, most of the patients in the CUR-QUE group showed an expedited clearance of the viral infection i.e., 18 (72.0%) vs. 6 (24.0%) patients in the control group tested negative for SARS-CoV-2 in the nasal-oropharyngeal swab reverse transcription-polymerase chain reaction (RT-PCR) analysis (p = 0.0002). In addition, COVID-19-associated acute symptoms were also speedily resolved in the CUR-QUE treated patients, i.e., 10 (40.0%) vs. 4 (16.0%) patients in the control group (p = 0.061). The CUR-QUE supplementation therapy was well-tolerated by all 25 patients and no treatment-emergent effects or serious adverse events were reported.

Conclusion

The results revealed in this exploratory study suggest a possible therapeutic role of curcumin and quercetin in the early-stage of COVID-19. It is proposed that the two agents possibly acting in synergy, interfere the SARS-CoV-2 replication, and thus help a speedy recovery in the early-stage of COVID-19. Further research is highly encouraged.

Clinical trial registration

Clinicaltrials.gov, Identifier NCT04603690.

Effect of nano-curcumin on various diseases: A comprehensive review of clinical trials

The antioxidant, anti-inflammatory, and antibacterial properties of curcumin have made it a valuable herbal product for improving various disorders, such as COVID-19, cancer, depression, anxiety, osteoarthritis, migraine, and diabetes. Recent research has demonstrated that encapsulating curcumin in nanoparticles might improve its therapeutic effects and bioavailability. To our knowledge, the efficacy of nano-curcumin on different aspects of health and disease has not been summarized in a study. Therefore, this review aimed to evaluate nano-curcumin's efficacy in various diseases based on the findings of clinical trials. In order to review publications focusing on nanocurcumin's impact on various diseases, four databases were searched, including PubMed, Scopus, Web of Science, and Google Scholar. This review highlights the potential benefits of nano-curcumin in improving a wide range of human diseases including COVID-19, neurological disorders, chronic disease, oral diseases, osteoarthritis, metabolic syndrome, and other diseases, especially as an adjunct to standard therapy and a healthy lifestyle.

Spices and Biomarkers of COVID-19: A Mechanistic and Therapeutic Perspective

In the face of the COVID-19 pandemic, many people around the world have increased their healthy behaviors to prevent transmission of the virus and potentially improve their immune systems. Therefore, the role of diet and food compounds such as spices with bioactive and antiviral properties may be important in these efforts. In this chapter, we review the efficacy of spices such as turmeric (curcumin), cinnamon, ginger, black pepper, saffron, capsaicin, and cumin by investigating the effects of these compounds of COVID-19 disease severity biomarkers.

Nano-Nutraceuticals for Health: Principles and Applications

The use of nanotechnological products is increasing steadily. In this scenario, the application of nanotechnology in food science and as a technological platform is a reality. Among the several applications, the main use of this technology is for the development of foods and nutraceuticals with higher bioavailability, lower toxicity, and better sustainability. In the health field, nano-nutraceuticals are being used as supplementary products to treat an increasing number of diseases. This review summarizes the main concepts and applications of nano-nutraceuticals for health, with special focus on treating cancer and inflammation.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s43450-022-00338-7.

Antiinflammatory Activities of Curcumin and Spirulina: Focus on Their Role against COVID-19

Nutraceuticals have for several years aroused the interest of researchers for their countless properties, including the management of viral infections. In the context of the COVID-19 pandemic, studies and research on the antiviral properties of nutraceuticals have greatly increased. More specifically, over the past two years, researchers have focused on analyzing the possible role of nutraceuticals in reducing the risk of SARS-CoV-2 infection or mitigating the symptoms of COVID-19. Among nutraceuticals, turmeric, extracted from the rhizome of the Curcuma Longa plant, and spirulina, commercial name of the cyanobacterium Arthrospira platensis, have assumed considerable importance in recent years. The purpose of this review is to collect, through a search of the most recent articles on Pubmed, the scientific evidence on the role of these two compounds in the fight against COVID-19. In the last two years many hypotheses, some confirmed by clinical and experimental studies, have been made on the possible use of turmeric against COVID-19, while on spirulina and its possible role against SARS-CoV-2 infection information is much less. The demonstrated antiviral properties of spirulina and the fact that these cyanobacteria may modulate or modify some mechanisms also involved in the onset of COVID-19, lead us to think that it may have the same importance as curcumin in fighting this disease and to speculate on the possible combined use of these two substances to obtain a synergistic effect.

Uncovering the information immunology journals transmitted for COVID-19: A bibliometric and visualization analysis

BACKGROUND

Since the global epidemic of the coronavirus disease 2019 (COVID-19), a large number of immunological studies related to COVID-19 have been published in various immunology journals. However, the results from these studies were discrete, and no study summarized the important immunological information about COVID-19 released by these immunology journals. This study aimed to comprehensively summarize the knowledge structure and research hotspots of COVID-19 published in major immunology journals through bibliometrics.

METHODS

Publications on COVID-19 in major immunology journals were obtained from the Web of Science Core Collection. CiteSpace, VOSviewer, and R-bibliometrix were comprehensively used for bibliometric and visual analysis.

RESULTS

1,331 and 5,000 publications of 10 journals with high impact factors and 10 journals with the most papers were included, respectively. The USA, China, England, and Italy made the most significant contributions to these papers. University College London, National Institute of Allergy and Infectious Diseases, Harvard Medical School, University California San Diego, and University of Pennsylvania played a central role in international cooperation in the immunology research field of COVID-19. Yuen Kwok Yung was the most important author in terms of the number of publications and citations, and the H-index. CLINICAL INFECTIOUS DISEASES and FRONTIERS IN IMMUNOLOGY were the most essential immunology journals. These immunology journals mostly focused on the following topics: "Delta/Omicron variants", "cytokine storm", "neutralization/neutralizing antibody", "T cell", "BNT162b2", "mRNA vaccine", "vaccine effectiveness/safety", and "long COVID".

CONCLUSION

This study systematically uncovered a holistic picture of the current research on COVID-19 published in major immunology journals from the perspective of bibliometrics, which will provide a reference for future research in this field.

A Review of In Silico Research, SARS-CoV-2, and Neurodegeneration: Focus on Papain-Like Protease

Since the appearance of SARS-CoV-2 and the COVID-19 pandemic, the search for new approaches to treat this disease took place in the scientific community. The in silico approach has gained importance at this moment, once the methodologies used in this kind of study allow for the identification of specific protein-ligand interactions, which may serve as a filter step for molecules that can act as specific inhibitors. In addition, it is a low-cost and high-speed technology. Molecular docking has been widely used to find potential viral protein inhibitors for structural and non-structural proteins of the SARS-CoV-2, aiming to block the infection and the virus multiplication. The papain-like protease (PLpro) participates in the proteolytic processing of SARS-CoV-2 and composes one of the main targets studied for pharmacological intervention by in silico methodologies. Based on that, we performed a systematic review about PLpro inhibitors from the perspective of in silico research, including possible therapeutic molecules in relation to this viral protein. The neurological problems triggered by COVID-19 were also briefly discussed, especially relative to the similarities of neuroinflammation present in Alzheimer's disease. In this context, we focused on two molecules, curcumin and glycyrrhizinic acid, given their PLpro inhibitory actions and neuroprotective properties and potential therapeutic effects on COVID-19.

Optimization of Anti-SARS-CoV-2 Treatments Based on Curcumin, Used Alone or Employed as a Photosensitizer

Curcumin, the bioactive compound of the spice Curcuma longa, has already been reported as a potential COVID-19 adjuvant treatment due to its immunomodulatory and anti-inflammatory properties. In this study, SARS-CoV-2 was challenged with curcumin; moreover, curcumin was also coupled with laser light at 445 nm in a photodynamic therapy approach. Curcumin at a concentration of 10 μM, delivered to the virus prior to inoculation on cell culture, inhibited SARS-CoV-2 replication (reduction >99%) in Vero E6 cells, possibly due to disruption of the virion structure, as observed using the RNase protection assay. However, curcumin was not effective as a prophylactic treatment on already-infected Vero E6 cells. Notably, when curcumin was employed as a photosensitizer and blue laser light at 445 nm was delivered to a mix of curcumin/virus prior to the inoculation on the cells, virus inactivation was observed (>99%) using doses of curcumin that were not antiviral by themselves. Photodynamic therapy employing crude curcumin can be suggested as an antiviral option against SARS-CoV-2 infection.

Are Nutraceuticals Effective in COVID-19 and Post-COVID Prevention and Treatment?

The beginning of the end or the end of the beginning? After two years mastered by coronavirus disease 19 (COVID-19) pandemic, we are now witnessing a turnaround. The reduction of severe cases and deaths from COVID-19 led to increasing importance of a new disease called post-COVID syndrome. The term post-COVID is used to indicate permanency of symptoms in patients who have recovered from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Immune, antiviral, antimicrobial therapies, as well as ozone therapy have been used to treat COVID-19 disease. Vaccines have then become available and administered worldwide to prevent the insurgence of the disease. However, the pandemic is not over yet at all given the emergence of new omicron variants. New therapeutic strategies are urgently needed. In this view, great interest was found in nutraceutical products, including vitamins (C, D, and E), minerals (zinc), melatonin, probiotics, flavonoids (quercetin), and curcumin. This review summarizes the role of nutraceuticals in the prevention and/or treatment of COVID-19 disease and post-COVID syndrome.

The dark side of Tregs during aging

In the last century, we have seen a dramatic rise in the number of older persons globally, a trend known as the grey (or silver) tsunami. People live markedly longer than their predecessors worldwide, due to remarkable changes in their lifestyle and in progresses made by modern medicine. However, the older we become, the more susceptible we are to a series of age-related pathologies, including infections, cancers, autoimmune diseases, and multi-morbidities. Therefore, a key challenge for our modern societies is how to cope with this fragile portion of the population, so that everybody could have the opportunity to live a long and healthy life. From a holistic point of view, aging results from the progressive decline of various systems. Among them, the distinctive age-dependent changes in the immune system contribute to the enhanced frailty of the elderly. One of these affects a population of lymphocytes, known as regulatory T cells (Tregs), as accumulating evidence suggest that there is a significant increase in the frequency of these cells in secondary lymphoid organs (SLOs) of aged animals. Although there are still discrepancies in the literature about modifications to their functional properties during aging, mounting evidence suggests a detrimental role for Tregs in the elderly in the context of bacterial and viral infections by suppressing immune responses against non-self-antigens. Interestingly, Tregs seem to also contribute to the reduced effectiveness of immunizations against many pathogens by limiting the production of vaccine-induced protective antibodies. In this review, we will analyze the current state of understandings about the role of Tregs in acute and chronic infections as well as in vaccination response in both humans and mice. Lastly, we provide an overview of current strategies for Treg modulation with potential future applications to improve the effectiveness of vaccines in older individuals.

Regulatory T Cells Decreased during Recovery from Mild COVID-19

Depending on the intensity and duration of SARS-CoV-2 infection, the host immune response plays a significant role in immunological protection. Here, we studied the regulatory T-cell (Treg) response in relation to kinetic change and cytokine production in patients with mild COVID-19. Nineteen SARS-CoV-2-positive patients were recruited, and blood was collected at four time points, i.e., seven days after admission, after discharge, and one and three months after recovery. CD3⁺CD4⁺CD25⁺CD127^low was marked as the Treg population, with IL-10 and TGF-β used to study cytokine-producing Tregs. IFN-γ-producing CD8⁺ T cells were observed for an effector response. The Treg percentage in patients with mild COVID-19 increased during hospitalization compared to during the recovery period. Peripheral blood mononuclear cells (PBMCs) were quantified, and the T-cell response was characterized by re-stimulation with S1 and N peptides. IL-10 and TGF-β were produced by CD25⁺CD127^low T cells during the active infection phase, especially with N peptide stimulation. Compared to N peptide stimulation, S1 peptide stimulation provided superior IFN-γ-secreting CD8⁺ T-cell responses. Our results suggest that while IFN-γ⁺CD8⁺ T cells confer antiviral immunity, cytokine-producing Tregs may have a substantial role in regulating inflammatory responses in mild SARS-CoV-2 infection. Novel vaccine development may also consider enhancing T-cell repertoires.

A comprehensive evaluation of the immune system response and type-I Interferon signaling pathway in hospitalized COVID-19 patients

BACKGROUND

The COVID-19 pandemic has become the world's main life-threatening challenge in the third decade of the twenty-first century. Numerous studies have been conducted on SARS-CoV2 virus structure and pathogenesis to find reliable treatments and vaccines. The present study aimed to evaluate the immune-phenotype and IFN-I signaling pathways of COVID-19 patients with mild and severe conditions.

MATERIAL AND METHODS

A total of 100 COVID-19 patients (50 with mild and 50 with severe conditions) were enrolled in this study. The frequency of CD4 + T, CD8 + T, Th17, Treg, and B lymphocytes beside NK cells was evaluated using flow cytometry. IFN-I downstream signaling molecules, including JAK-1, TYK-2, STAT-1, and STAT-2, and Interferon regulatory factors (IRF) 3 and 7 expressions at RNA and protein status were investigated using real-time PCR and western blotting techniques, respectively. Immune levels of cytokines (e.g., IL-1β, IL-6, IL-17, TNF-α, IL-2R, IL-10, IFN-α, and IFN-β) and the existence of anti-IFN-α autoantibodies were evaluated via enzyme-linked immunosorbent assay (ELISA).

RESULTS

Immune-phenotyping results showed a significant decrease in the absolute count of NK cells, CD4 + T, CD8 + T, and B lymphocytes in COVID-19 patients. The frequency of Th17 and Treg cells showed a remarkable increase and decrease, respectively. All signaling molecules of the IFN-I downstream pathway and IRFs (i.e., JAK-1, TYK-2, STAT-1, STAT-2, IRF-3, and IRF-7) showed very reduced expression levels in COVID-19 patients with the severe condition compared to healthy individuals at both RNA and protein levels. Of 50 patients with severe conditions, 14 had anti-IFN-α autoantibodies in sera. Meanwhile, this result was 2 and 0 for patients with mild symptoms and healthy controls, respectively.

CONCLUSION

Our results indicate a positive association of the existence of anti-IFN-α autoantibodies and immune cells dysregulation with the severity of illness in COVID-19 patients. However, comprehensive studies are necessary to find out more about this context. Video abstract.

Oral Co-Supplementation of Curcumin, Quercetin, and Vitamin D3 as an Adjuvant Therapy for Mild to Moderate Symptoms of COVID-19—Results From a Pilot Open-Label, Randomized Controlled Trial

Background: Curcumin, quercetin, and vitamin D3 (cholecalciferol) are common natural ingredients of human nutrition and reportedly exhibit promising anti-inflammatory, immunomodulatory, broad-spectrum antiviral, and antioxidant activities.

Objective: The present study aimed to investigate the possible therapeutic benefits of a single oral formulation containing supplements curcumin, quercetin, and cholecalciferol (combinedly referred to here as CQC) as an adjuvant therapy for early-stage of symptomatic coronavirus disease 2019 (COVID-19) in a pilot open-label, randomized controlled trial conducted at Mayo Hospital, King Edward Medical University, Lahore, Pakistan.

Methods: Reverse transcriptase polymerase chain reaction (RT-PCR) confirmed, mild to moderate symptomatic COVID-19 outpatients were randomized to receive either the standard of care (SOC) (n = 25) (control arm) or a daily oral co-supplementation of 168 mg curcumin, 260 mg quercetin, and 9 µg (360 IU) of cholecalciferol, as two oral soft capsules b.i.d. as an add-on to the SOC (n = 25) (CQC arm) for 14 days. The SOC includes paracetamol with or without antibiotic (azithromycin). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RT-PCR test, acute symptoms, and biochemistry including C-reactive protein (CRP), D-dimer, lactate dehydrogenase, ferritin, and complete blood count were evaluated at baseline and follow-up day seven.

Results: Patients who received the CQC adjuvant therapy showed expedited negativization of the SARS-CoV-2 RT-PCR test, i.e., 15 (60.0%) vs. five (20.0%) of the control arm, p = 0.009. COVID-19- associated acute symptoms were rapidly resolved in the CQC arm, i.e., 15 (60.0%) vs. 10 (40.0%) of the control arm, p = 0.154. Patients in the CQC arm experienced a greater fall in serum CRP levels, i.e., from (median (IQR) 34.0 (21.0, 45.0) to 11.0 (5.0, 16.0) mg/dl as compared to the control arm, i.e., from 36.0 (28.0, 47.0) to 22.0 (15.0, 25.0) mg/dl, p = 0.006. The adjuvant therapy of co-supplementation of CQC was safe and well-tolerated by all 25 patients and no treatment-emergent effects, complications, side effects, or serious adverse events were reported.

Conclusion: The co-supplementation of CQC may possibly have a therapeutic role in the early stage of COVID-19 infection including speedy negativization of the SARS-CoV-2 RT-PCR test, resolution of acute symptoms, and modulation of the hyperinflammatory response. In combination with routine care, the adjuvant co-supplementation of CQC may possibly help in the speedy recovery from early-stage mild to moderate symptoms of COVID-19. Further research is warranted.

Clinical Trial Registration:Clinicaltrials.gov, identifier NCT05130671

The efficacy of curcumin-piperine co-supplementation on clinical symptoms, duration, severity, and inflammatory factors in COVID-19 outpatients: a randomized double-blind, placebo-controlled trial

BACKGROUND

COVID-19 pandemic has made the disease a major global problem by creating a significant burden on health, economic, and social status. To date, there are no effective and approved medications for this disease. Curcumin as an anti-inflammatory agent can have a positive effect on the control of COVID-19 complications. This study aimed to assess the efficacy of curcumin-piperine supplementation on clinical symptoms, duration, severity, and inflammatory factors in patients with COVID-19.

METHODS

Forty-six outpatients with COVID-19 disease were randomly allocated to receive two capsules of curcumin-piperine; each capsule contained 500 mg curcumin plus 5 mg piperine or placebo for 14 days.

RESULTS

Mean changes in complete blood count, liver enzymes, blood glucose levels, lipid parameters, kidney function, and c-reactive protein (CRP) were not significantly different between the two groups. There was a significant improvement in health status, including dry cough, sputum cough, ague, sore throat, weakness, muscular pain, headache, and dyspnea at week 2 in both curcumin-piperine and placebo groups (P value < 0.05); however, the improvement in weakness was more in the curcumin-piperine group than with placebo group (P value 025).

CONCLUSION

The present study results showed that curcumin-piperine co-supplementation in outpatients with COVID-19 could significantly reduce weakness. However, in this study, curcumin-piperine co-supplementation could not significantly affect the other indices, including biochemical and clinical indices.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20121216011763N46 . 2020-10-31.

Filamentous bacteriophages, natural nanoparticles, for viral vaccine strategies

Filamentous bacteriophages are natural nanoparticles formed by the self-assembly of structural proteins that have the capability of replication and infection. They are used as a highly efficient vaccine platform to enhance immunogenicity and effectively stimulate the innate and adaptive immune response. Compared with traditional vaccines, phage-based vaccines offer thermodynamic stability, biocompatibility, homogeneity, high carrying capacity, self-assembly, scalability, and low toxicity. This review summarizes recent research on phage-based vaccines in virus prevention. In addition, the expression systems of filamentous phage-based virus vaccines and their application principles are discussed. Moreover, the prospect of the prevention of emerging infectious diseases, such as coronavirus 2019 (COVID-19), is also discussed.

Pharmaceutical Prospects of Curcuminoids for the Remedy of COVID-19: Truth or Myth

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is a positive-strand RNA virus, and has rapidly spread worldwide as a pandemic. The vaccines, repurposed drugs, and specific treatments have led to a surge of novel therapies and guidelines nowadays; however, the epidemic of COVID-19 is not yet fully combated and is still in a vital crisis. In repositioning drugs, natural products are gaining attention because of the large therapeutic window and potent antiviral, immunomodulatory, anti-inflammatory, and antioxidant properties. Of note, the predominant curcumoid extracted from turmeric (Curcuma longa L.) including phenolic curcumin influences multiple signaling pathways and has demonstrated to possess anti-inflammatory, antioxidant, antimicrobial, hypoglycemic, wound healing, chemopreventive, chemosensitizing, and radiosensitizing spectrums. In this review, all pieces of current information related to curcumin-used for the treatment and prevention of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through in vitro, in vivo, and in silico studies, clinical trials, and new formulation designs are retrieved to re-evaluate the applications based on the pharmaceutical efficacy of clinical therapy and to provide deep insights into knowledge and strategy about the curcumin's role as an immune booster, inflammatory modulator, and therapeutic agent against COVID-19. Moreover, this study will also afford a favorable application or approach with evidence based on the drug discovery and development, pharmacology, functional foods, and nutraceuticals for effectively fighting the COVID-19 pandemic.

Nanotechnology-based therapeutics for targeting inflammatory lung diseases

The physiochemical properties of drugs used in treating inflammation-associated lung diseases (i.e., asthma, chronic obstructive pulmonary disease, pulmonary fibrosis) play an important role in determining the effectiveness of formulations. Most commonly used drugs are associated with low solubility, low stability and rapid clearance, thus resulting in low bioavailability and therapeutic index. This review focuses on current trends and development of drugs (i.e., corticosteroids, long-acting β-agonists and biomacromolecules such as DNA, siRNA and mRNA) employed to treat inflammatory lung diseases. In addition, this review includes the current challenges of and future perspective with regard to nanotechnology in the treatment of inflammatory lung diseases.

The effects of curcumin as dietary supplement for patients with COVID-19: A systematic review of randomized clinical trials

Accumulating evidence has been reported regarding the effect of curcumin as a dietary antiviral on patients with COVID-19; however, findings are controversial. Our systematic review aimed to evaluate the effects of curcumin in patients with COVID-19. Electronic databases (PubMed, EMBASE, Scopus, Web of Science, Cochrane Central, and Google Scholar) were systematically searched to identify only randomized clinical trials (RCTs) that assessed curcumin in patients with COVID-19 from inception to September 23, 2021 relevant keywords. The Cochrane risk-of-bias tool for randomized trials was used to evaluate the risk of bias. After a critical review of 1,098 search hits, only six RCTs were selected for discussion. A total of 480 patients were included, with 240 amongst the curcumin groups and 240 in the control group. The lymphocyte count was significantly higher in the curcumin group compared to the placebo group. Curcumin was found to decrease the number of T-helper 17 cells, downregulate T-helper-17 cell-related factors, reduce levels of T-helper-17 cell-related cytokines, yet increase the gene expression of Treg transcription factor forkhead box P3 (FOXP3), and decrease T-Box transcription factor 21 (TBX21). Our review revealed that curcumin might have a positive effect on relieving COVID-19 related inflammatory response due to its powerful immune-modulatory effects on cytokines production, T-cell responses, and gene expression. These findings suggest that curcumin confers clinical benefits in patients with COVID-19. However, due to the limited number of the included studies, further high-quality studies are needed to establish the clinical efficacy of the curcumin.

A DNA Biosensor Based on a Raspberry-like Hierarchical Nano-structure for the Determination of the Anticancer Drug Nilotinib

It is crucial to design fast, sensitive and affordable deoxyribonucleic acid (DNA) recognition instruments, and elucidate changes in DNA structure, for studying the interaction between DNA and chemotherapy drugs. Therefore, a DNA biosensor, based on a carbon paste electrode (CPE), modified with raspberry-like indium(III)/nickel oxide hierarchical nano-structures (In3+ /NiO RLHNSs) was constructed. An electrochemical readout should then give information on the interactions between anticancer drugs and double-stranded (ds)-DNA. The morphology as well as the electrochemical description of this new biosensor is described. Based on experimentally determined optimal conditions, ds-DNA modified with In3+ /NiO RLHNSs/CPE was used to evaluate the binding interaction of nilotinib, as an anti-cancer drug, with DNA through differential pulse voltammetry (DPV), UV-Vis spectroscopy, viscosity measurements and a computational docking process. The analyses indicated the linearity of the guanine oxidation signal at nilotinib concentration is given between 0.01 and 50.0 μm, with the limit of detection (LOD) equal to 0.62 nm. Additionally, the equilibrium constant (K) for the binding was determined to 1.5×104  m-1 . Through the quantitative measurement of nilotinib in serum samples with a high recovery rate of 101.3-98.0 %, the applicability of this approach was demonstrated. As a whole, this DNA biosensor may be promising for various bio-interactions.

Nanocurcumin formulation: a possible therapeutic agent for post COVID inflammatory syndrome

Over the last twenty months, the attention of the world has been focusing on managing the unprecedented and devastating wave of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV 2) and mitigating its impacts. Recent findings indicated that high levels of pro-inflammatory cytokines are leading cause of poor prognosis in severely ill COVID-19 patients. Presently, the multiple variants and highly contagious nature of virus makes challenge humongous. The shortage and vaccine hesitancy also prompted to develop antiviral therapeutic agents to manage this pandemic. Nanocurcumin has potential antiviral activities and also beneficial in post COVID inflammatory complications. We have developed nanocurcumin based formulation using pyrroloquinoline quinone (PQQ) which protects cardio-pulmonary function and mitochondrial homeostasis in hypobaric hypoxia induced right ventricular hypertrophy in animal model and human ventricular cardiomyocytes. Nanocurcumin based formulation (NCF) with improved bioavailability, has proven several holistic therapeutic effects including myocardial protection, and prevents edema formation, anti-inflammatory and antioxidant properties, maintaining metabolic and mitochondrial homeostasis under hypoxic condition. The post COVID-inflammatory syndrome also reported to cause impaired heart function, lung injuries and increased C-reactive protein level in severely ill patients. Thus, we speculate that NCF could be a new treatment option to manage post COVID-19 inflammatory syndrome.

Effectiveness of Curcumin on Outcomes of Hospitalized COVID-19 Patients: A Systematic Review of Clinical Trials

Despite the ongoing vaccination efforts, there is still an urgent need for safe and effective treatments to help curb the debilitating effects of COVID-19 disease. This systematic review aimed to investigate the efficacy of supplemental curcumin treatment on clinical outcomes and inflammation-related biomarker profiles in COVID-19 patients. We searched PubMed, Scopus, Web of Science, EMBASE, ProQuest, and Ovid databases up to 30 June 2021 to find studies that assessed the effects of curcumin-related compounds in mild to severe COVID-19 patients. Six studies were identified which showed that curcumin supplementation led to a significant decrease in common symptoms, duration of hospitalization and deaths. In addition, all of these studies showed that the intervention led to amelioration of cytokine storm effects thought to be a driving force in severe COVID-19 cases. This was seen as a significant (p < 0.05) decrease in proinflammatory cytokines such as IL1β and IL6, with a concomitant significant (p < 0.05) increase in anti-inflammatory cytokines, including IL-10, IL-35 and TGF-α. Taken together, these findings suggested that curcumin exerts its beneficial effects through at least partial restoration of pro-inflammatory/anti-inflammatory balance. In conclusion, curcumin supplementation may offer an efficacious and safe option for improving COVID-19 disease outcomes. We highlight the point that future clinical studies of COVID-19 disease should employ larger cohorts of patients in different clinical settings with standardized preparations of curcumin-related compounds.

Emerging importance of nanotechnology-based approaches to control the COVID-19 pandemic; focus on nanomedicine iterance in diagnosis and treatment of COVID-19 patients

The ongoing outbreak of the newly emerged coronavirus disease 2019, which has tremendously concerned global health safety, is the result of infection with severe acute respiratory syndrome of coronavirus 2 with high morbidity and mortality. Because of the coronavirus has no specific treatment, so it is necessary to early detection and produce antiviral agents and efficacious vaccines in order to prevent the contagion of coronavirus. Due to the unique properties of nanomaterials, nanotechnology appears to be a highly relevant discipline in this global emergency, providing expansive chemical functionalization to develop advanced biomedical tools. Fascinatingly, nanomedicine as a hopeful approach for the treatment and diagnosis of diseases, could efficiently help success the fight among coronavirus and host cells. In this review, we will critically discuss how nanomedicine can play an indispensable role in creating useful treatments and diagnostics for coronavirus.

Nanovesicles containing curcumin hold promise in the development of new formulations of anti-Acanthamoebic agents

In this study, curcumin-nanoformulations were tested for anti-Acanthamoebic properties. Curcumin-loaded nanovesicles were synthesized, followed by characterization with Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometry, and atomic force microscopy. Using amoebicidal assay, the effects of curcumin-nanoformulations were investigated against A. castellanii belonging to the T4 genotype. To determine the effects of curcumin-nanoformulations on host cells, cytotoxicity assays were performed using human keratinocyte cells (HaCat). The results revealed that nanovesicles formulation of curcumin enhanced the anti-Acanthamoebic effects of curcumin as compared with curcumin alone. The viability decreased with increasing concentration of curcumin and/or lipid-based carrier (Noisome) (FCBR18) in a dose-dependent manner. Curcumin and curcumin-loaded nanovesicles exhibited minimal cytotoxic effects against human cells in all tested concentrations. Both concentrations of FCBR18 proved effective in inhibiting amoebae excystation. In contrast, curcumin alone showed insignificant effects against amoebae excystation. Taken together, these findings clearly showed that curcumin-loaded nanovesicles show enhanced anti-Acanthamoebic efficacy without harming human cells, and these nanotherapeutics may hold promise in the development of new formulations of anti-Acanthamoebic agents.

Anti-Inflammatory Effects of Curcumin in the Inflammatory Diseases: Status, Limitations and Countermeasures

Curcumin is a natural compound with great potential for disease treatment. A large number of studies have proved that curcumin has a variety of biological activities, among which anti-inflammatory effect is a significant feature of it. Inflammation is a complex and pervasive physiological and pathological process. The physiological and pathological mechanisms of inflammatory bowel disease, psoriasis, atherosclerosis, COVID-19 and other research focus diseases are not clear yet, and they are considered to be related to inflammation. The anti-inflammatory effect of curcumin can effectively improve the symptoms of these diseases and is expected to be a candidate drug for the treatment of related diseases. This paper mainly reviews the anti-inflammatory effect of curcumin, the inflammatory pathological mechanism of related diseases, the regulatory effect of curcumin on these, and the latest research results on the improvement of curcumin pharmacokinetics. It is beneficial to the further study of curcumin and provides new ideas and insights for the development of curcumin anti-inflammatory preparations.

Recent advances in antibody-based immunotherapy strategies for COVID-19

The emergence of a new acute respiratory syndrome Coronavirus 2 (SARS-CoV-2), the cause of the 2019-nCOV disease (COVID-19), has caused a pandemic and a global health crisis. Rapid human-to-human transmission, even from asymptomatic individuals, has led to the quick spread of the virus worldwide, causing a wide range of clinical manifestations from cold-like symptoms to severe pneumonia, acute respiratory distress syndrome (ARDS), multiorgan injury, and even death. Therefore, using rapid and accurate diagnostic methods to identify the virus and subsequently select appropriate and effective treatments can help improvement of patients and control the pandemic. So far, various treatment regimens along with prophylactic vaccines have been developed to manage COVID-19-infected patients. Among these, antibody-based therapies, including neutralizing antibodies (against different parts of the virus), polyclonal and monoclonal antibodies, plasma therapy, and high-dose intravenous immunoglobulin (IVIG) have shown promising outcomes in accelerating and improving the treatment process of patients, avoiding the viral spreading widely, and managing the pandemic. In the current review paper, different types and applications of therapeutic antibodies in the COVID-19 treatment are comprehensively discussed.

Consumption of Phenolic-Rich Food and Dietary Supplements as a Key Tool in SARS-CoV-19 Infection

The first cases of COVID-19, which is caused by the SARS-CoV-2, were reported in December 2019. The vertiginous worldwide expansion of SARS-CoV-2 caused the collapse of health systems in several countries due to the high severity of the COVID-19. In addition to the vaccines, the search for active compounds capable of preventing and/or fighting the infection has been the main direction of research. Since the beginning of this pandemic, some evidence has highlighted the importance of a phenolic-rich diet as a strategy to reduce the progression of this disease, including the severity of the symptoms. Some of these compounds (e.g., curcumin, gallic acid or quercetin) already showed capacity to limit the infection of viruses by inhibiting entry into the cell through its binding to protein Spike, regulating the expression of angiotensin-converting enzyme 2, disrupting the replication in cells by inhibition of viral proteases, and/or suppressing and modulating the host's immune response. Therefore, this review intends to discuss the most recent findings on the potential of phenolics to prevent SARS-CoV-2.

Efficacy of phytochemicals as immunomodulators in managing COVID-19: a comprehensive view

Throughout history, disease outbreaks have worked havoc upon humanity, sometimes reorienting the history and at times, signaling the end of entire civilizations and the modern pandemic that the world is dealing with, is COVID-19 or SARS-CoV-2. A healthy immunity could be an ideal gear for resisting COVID-19 for neither medicines nor vaccines have been ascertained till date. In view of the present scenario, there is a demanding necessity to analyze innovative and valid techniques for forestalling and cure of COVID-19 by re-evaluating the structure of the natural compounds for drug designing. The Ayurveda has come forward by prescribing a lot of medicinal herbs for combating this dreaded disease. We have searched from sources in Pubmed and Google Scholar and found 1509 items. The search criteria were limited to the effect of phytochemicals in certain immunomodulatory aspects of viral infection. The original research papers related to the works on phytochemicals in the down regulation of NF-kB, activation of NK and CD8+ cells, inhibition of inflammatory cytokine release and ROS scavenging were included in our study. Here, we try to focus on the immunoregulatory cells which have a vital aspect in COVID-19 and highlight the potential effects of the restorative use of phytochemicals as drugs or dietary supplements.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13337-021-00706-2.

Interplay between Neutrophils, NETs and T-Cells in SARS-CoV-2 Infection-A Missing Piece of the Puzzle in the COVID-19 Pathogenesis?

Since the end of 2019, a new, dangerous virus has caused the deaths of more than 3 million people. Efforts to fight the disease remain multifaceted and include prophylactic strategies (vaccines), the development of antiviral drugs targeting replication, and the mitigation of the damage associated with exacerbated immune responses (e.g., interleukin-6-receptor inhibitors). However, numerous uncertainties remain, making it difficult to lower the mortality rate, especially among critically ill patients. While looking for a new means of understanding the pathomechanisms of the disease, we asked a question-is our immunity key to resolving these uncertainties? In this review, we attempt to answer this question, and summarize, interpret, and discuss the available knowledge concerning the interplay between neutrophils, neutrophil extracellular traps (NETs), and T-cells in COVID-19. These are considered to be the first line of defense against pathogens and, thus, we chose to emphasize their role in SARS-CoV-2 infection. Although immunologic alterations are the subject of constant research, they are poorly understood and often underestimated. This review provides background information for the expansion of research on the novel, immunity-oriented approach to diagnostic and treatment possibilities.