COVID-19: A Case for Inhibiting NLRP3 Inflammasome, Suppression of Inflammation with Curcumin?
Basic & clinical pharmacology & toxicology. 2021;(1):37-45
Curcumin is the effective ingredient of turmeric, sometimes used as a painkiller in traditional medicine. It has extensive biological properties such as anti-inflammatory and antioxidant activities. SARS-CoV-2 is a betacoronavirus developing severe pneumonitis. Inflammasome is one of the most important components of innate immunity, which exacerbates inflammation by increasing IL-1β and IL-18 production. Studies on viral infections have shown overactivity of inflammasome and thus the occurrence of destructive and systemic inflammation in patients. NLRP3 inflammasome has been shown to play a key role in the pathogenesis of viral diseases. The proliferation of SARS-CoV-2 in a wide range of cells can be combined with numerous observations of direct and indirect activation of inflammasome by other coronaviruses. Activation of the inflammasome is likely to be involved in the formation of cytokine storm. Curcumin regulates several molecules in the intracellular signal transduction pathways involved in inflammation, including IBB, NF-kBERK1,2, AP-1, TGF-β, TXNIP, STAT3, PPARγ, JAK2-STAT3, NLRP3, p38MAPK, Nrf2, Notch-1, AMPK, TLR-4 and MyD-88. Due to anti-inflammatory and anti-inflammasome properties without any special side effects, curcumin can potentially play a role in the treatment of COVID-19 infection along with other drug regimens.
Repurposing potential of Ayurvedic medicinal plants derived active principles against SARS-CoV-2 associated target proteins revealed by molecular docking, molecular dynamics and MM-PBSA studies.
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie. 2021;:111356
All the plants and their secondary metabolites used in the present study were obtained from Ayurveda, with historical roots in the Indian subcontinent. The selected secondary metabolites have been experimentally validated and reported as potent antiviral agents against genetically-close human viruses. The plants have also been used as a folk medicine to treat cold, cough, asthma, bronchitis, and severe acute respiratory syndrome in India and across the globe since time immemorial. The present study aimed to assess the repurposing possibility of potent antiviral compounds with SARS-CoV-2 target proteins and also with host-specific receptor and activator protease that facilitates the viral entry into the host body. Molecular docking (MDc) was performed to study molecular affinities of antiviral compounds with aforesaid target proteins. The top-scoring conformations identified through docking analysis were further validated by 100 ns molecular dynamic (MD) simulation run. The stability of the conformation was studied in detail by investigating the binding free energy using MM-PBSA method. Finally, the binding affinities of all the compounds were also compared with a reference ligand, remdesivir, against the target protein RdRp. Additionally, pharmacophore features, 3D structure alignment of potent compounds and Bayesian machine learning model were also used to support the MDc and MD simulation. Overall, the study emphasized that curcumin possesses a strong binding ability with host-specific receptors, furin and ACE2. In contrast, gingerol has shown strong interactions with spike protein, and RdRp and quercetin with main protease (Mpro) of SARS-CoV-2. In fact, all these target proteins play an essential role in mediating viral replication, and therefore, compounds targeting aforesaid target proteins are expected to block the viral replication and transcription. Overall, gingerol, curcumin and quercetin own multitarget binding ability that can be used alone or in combination to enhance therapeutic efficacy against COVID-19. The obtained results encourage further in vitro and in vivo investigations and also support the traditional use of antiviral plants preventively.
Nano-curcumin therapy, a promising method in modulating inflammatory cytokines in COVID-19 patients.
International immunopharmacology. 2020;(Pt B):107088
BACKGROUND As an ongoing worldwide health issue, Coronavirus disease 2019 (COVID-19) has been causing serious complications, including pneumonia, acute respiratory distress syndrome (ARDS), and multi-organ failure. However, there is no decisive treatment approach available for this disorder, which is primarily attributed to the large amount of inflammatory cytokine production. We aimed to identify the effects of Nano-curcumin on the modulation of inflammatory cytokines in COVID-19 patients. METHOD Forty COVID-19 patients and 40 healthy controls were recruited and evaluated for inflammatory cytokine expression and secretion. Subsequently, COVID-19 patients were divided into two groups: 20 patients receiving Nano-curcumin and 20 patients as the placebo group. The mRNA expression and cytokine secretion levels of IL-1β, IL-6, TNF-α and IL-18 were assessed by Real-time PCR and ELISA, respectively. RESULT Our primary results indicated that the mRNA expression and cytokine secretion of IL-1β, IL-6, TNF-α, and IL-18 were increased significantly in COVID-19 patients compared with healthy control group. After treatment with Nano-curcumin, a significant decrease in IL-6 expression and secretion in serum and in supernatant (P = 0.0003, 0.0038, and 0.0001, respectively) and IL-1β gene expression and secretion level in serum and supernatant (P = 0.0017, 0.0082, and 0.0041, respectively) was observed. However, IL-18 mRNA expression and TNF-α concentration were not influenced by Nano-curcumin. CONCLUSION Nano-curcumin, as an anti-inflammatory herbal based agent, may be able to modulate the increased rate of inflammatory cytokines especially IL-1β and IL-6 mRNA expression and cytokine secretion in COVID-19 patients, which may cause an improvement in clinical manifestation and overall recovery.
Potential effects of curcumin in the treatment of COVID-19 infection.
Phytotherapy research : PTR. 2020;(11):2911-2920
Coronavirus disease 2019 (COVID-19) outbreak is an ongoing pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with considerable mortality worldwide. The main clinical manifestation of COVID-19 is the presence of respiratory symptoms, but some patients develop severe cardiovascular and renal complications. There is an urgency to understand the mechanism by which this virus causes complications so as to develop treatment options. Curcumin, a natural polyphenolic compound, could be a potential treatment option for patients with coronavirus disease. In this study, we review some of the potential effects of curcumin such as inhibiting the entry of virus to the cell, inhibiting encapsulation of the virus and viral protease, as well as modulating various cellular signaling pathways. This review provides a basis for further research and development of clinical applications of curcumin for the treatment of newly emerged SARS-CoV-2.
Effects of curcumin-piperine co-supplementation on clinical signs, duration, severity, and inflammatory factors in patients with COVID-19: a structured summary of a study protocol for a randomised controlled trial.
OBJECTIVES This study aims to investigate the efficacy of curcumin-piperine co-supplementation on disease duration, severity and clinical symptoms, and inflammatory mediators in patients with coronavirus (COVID-19). TRIAL DESIGN This is a randomized, placebo-controlled, double-blind, parallel arm clinical trial. PARTICIPANTS All patients aged 20-75 years with the diagnosis of Covid-19 based on the PCR test. The exclusion criteria will include an age less than 20 and more than 75 years, current use of warfarin or other anticoagulant drugs, and the presence of sensitivity to herbal products such as turmeric and pepper. This study will be conducted in academic hospitals affiliated to Isfahan University of Medical Sciences, Isfahan, Iran. INTERVENTION AND COMPARATOR Fifty outpatients will be randomly allocated in a ratio of 1:1 to receive a capsule of curcumin-piperine containing 500 mg curcumin plus 5 mg piperine or matching placebo containing 505 mg maltodextrin twice a daily, after lunch and dinner, over a period of 2 weeks. Similarly, 50 inpatients who are admitted to hospital wards excluding intensive care unit (ICU) will be randomly assigned in a ratio of 1:1 to receive a capsule curcumin-piperine or matching placebo (provided by the Sami Labs company) twice a daily, after lunch and dinner, over a period of 2 weeks. MAIN OUTCOMES The main outcomes of this study are the efficacy of curcumin-piperine on coronavirus disease's clinical symptoms, duration, severity, and inflammatory mediators after 2 weeks of curcumin-piperine co-supplementation. RANDOMISATION Randomization sequences will be generated with the use of a random-number table with a permuted block design (block size of 4) and stratification according to the gender variable (male vs. female). These sequences will be prepared by an independent statistician and will be kept in opaque, sealed, numbered envelopes which will be opened only at the time of enrollment. The allocation ratio in intervention and control groups is 1:1. Researchers and all patients will be unaware of the study-group assignment until the completion of data analyses. BLINDING (MASKING): This study is a double-blind clinical trial (participant, researcher). The curcumin-piperine and placebo supplements are packaged in similar numbered drug containers, and the researcher and all patients will be unaware of the study assignment until the end of the study. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): The calculated total sample size is 100 patients, with 25 patients in each group. TRIAL STATUS The protocol is Version 2.0, May 24, 2020. Recruitment began May 4, 2020, and is anticipated to be completed by April 19, 2021. TRIAL REGISTRATION This trial has been registered by the title of "Effect of curcumin-piperine co-supplementation on disease duration, severity and clinical signs, and inflammatory factors in patients with coronavirus (COVID-19): A randomized, double-blind, placebo-controlled clinical trial study" in the Iranian Registry of Clinical Trials (IRCT) with code "IRCT20121216011763N46", https://www.irct.ir/trial/47529 . The registration date is May 4, 2020. FULL PROTOCOL The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.