Curcumin Attenuates Airway Inflammation and Airway Remolding by Inhibiting NF-κB Signaling and COX-2 in Cigarette Smoke-Induced COPD Mice

Targeting ferroptosis using Chinese herbal compounds to treat respiratory diseases

BACKGROUND

Respiratory diseases pose a grave threat to human life. Therefore, understanding their pathogenesis and therapeutic strategy is important. Ferroptosis is a novel type of iron-dependent programmed cell death, distinct from apoptosis, necroptosis, and autophagy, characterised by iron, reactive oxygen species, and lipid peroxide accumulation, as well as glutathione (GSH) depletion and GSH peroxidase 4 (GPX4) inactivation. A close association between ferroptosis and the onset and progression of respiratory diseases, including chronic obstructive pulmonary disease, acute lung injury, bronchial asthma, pulmonary fibrosis, and lung cancer, has been reported. Recent studies have shown that traditional Chinese medicine (TCM) compounds exhibit unique advantages in the treatment of respiratory diseases owing to their natural properties and potential efficacy. These compounds can effectively regulate ferroptosis by modulating several key signalling pathways such as system Xc- -GSH-GPX4, NCOA4-mediated ferritinophagy, Nrf2-GPX4, and Nrf2/HO-1, thus playing a positive role in improving respiratory diseases.

PURPOSE

This comprehensive review systematically outlines the regulatory role of ferroptosis in the onset and progression of respiratory diseases and provides evidence for treating respiratory diseases by targeting ferroptosis with TCM compounds. These insights aim to offer potential remedies for the clinical prevention and treatment of respiratory diseases.

STUDY DESIGN AND METHODS

We searched scientific databases PubMed, Web of Science, Scopus, and CNKI using keywords such as "ferroptosis","respiratory diseases","chronic obstructive pulmonary disease","bronchial asthma","acute lung injury","pulmonary fibrosis","lung cancer","traditional Chinese medicine","traditional Chinese medicine compound","monomer", and "natural product" to retrieve studies on the therapeutic potential of TCM compounds in ameliorating respiratory diseases by targeting ferroptosis. The retrieved data followed PRISMA criteria (preferred reporting items for systematic review).

RESULTS

TCM compounds possess unique advantages in treating respiratory diseases, stemming from their natural origins and proven clinical effectiveness. TCM compounds can exert therapeutic effects on respiratory diseases by regulating ferroptosis, which mainly involves modulation of pathways such as system Xc- -GSH-GPX4,NCOA4-mediated ferritinophagy, Nrf2-GPX4, and Nrf2/HO-1.

CONCLUSION

TCM compounds have demonstrated promising potential in improving respiratory diseases through the regulation of ferroptosis. The identification of specific TCM-related inducers and inhibitors of ferroptosis holds great significance in developing more effective strategies. However, current research remains confined to animal and cellular studies, emphasizing the imperative for further verifications through high-quality clinical data.

Unraveling the protective effects of curcumin against drugs of abuse

Curcumin, a natural compound derived from the turmeric plant (Curcuma longa), has garnered significant attention for its diverse neuroprotective properties. Curcumin has been widely recognized for its remarkable anti-inflammatory, antioxidant, and anti-apoptotic effects, which have shown great potential in the treatment of various disorders, encompassing psychiatric and neurodegenerative diseases. In this review, we delve into the protective effects of curcumin against drugs of abuse, including morphine, methamphetamine, cocaine, nicotine, and alcohol, with a particular focus on the underlying mechanisms from a neuroscience perspective. Overall, curcumin demonstrates promising effects against the neurotoxicity induced by abused drugs through a wide range of mechanisms. These include the modulation of inflammatory cytokines, maintenance of ion homeostasis, epigenetic regulation, enhancement of antioxidant capacity, as well as the activation of the cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) signaling pathways. These findings suggest that curcumin emerges as a promising therapeutic agent in combatting the detrimental effects induced by drugs of abuse, and further research is warranted to fully comprehend the molecular pathways and optimize its utilization for the prevention and treatment of substance abuse-related neurotoxicity.

Nanocurcumin modulates Th17 cell responses in moderate and severe COPD patients

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory process in the airways that results in airflow obstruction. It is mainly linked to cigarette smoke exposure. Th17 cells have a role in the pathogenesis of COPD by secreting pro-inflammatory cytokines, which cause hyperinflammation and progression of the disease. This study aimed to assess the potential therapeutic effects of nanocurcumin on the Th17 cell frequency and its responses in moderate and severe COPD patients. This study included 20 patients with severe COPD hospitalized in an intensive care unit (ICU) and 20 patients with moderate COPD. Th17 cell frequency, Th17-related factors gene expression (RAR-related orphan receptor t (RORγt), IL-17, IL-21, IL-23, and granulocyte-macrophage colony-stimulating factor), and serum levels of Th17-related cytokines were assessed before and after treatment in both placebo and nanocurcumin-treated groups using flow cytometry, real-time PCR, and ELISA, respectively. According to our findings, in moderate and severe nanocurcumin-treated COPD patients, there was a substantial reduction in the frequency of Th17 cells, mRNA expression, and cytokines secretion level of Th17-related factors compared to the placebo group. Furthermore, after treatment, the metrics mentioned above were considerably lower in the nanocurcumin-treated group compared to before treatment. Nanocurcumin has been shown to decrease the number of Th17 cells and their related inflammatory cytokines in moderate and severe COPD patients. As a result, it might be used as an immune-modulatory agent to alleviate the patient's inflammatory state.

Codonopsis Radix Inhibits the Inflammatory Response and Oxidative Stress in Chronic Obstructive Pulmonary Disease Mice through Regulation of the Nrf2/NF-κB Signaling Pathway

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a nonspecific chronic inflammatory lung disease with no known cure. Codonopsis Radix (CR) has been shown to exhibit anti-inflammatory and antioxidant effects. Therefore, this study aimed to investigate the potential anti-inflammatory effects of different CR varieties on COPD mice.

METHODS

Sixty male-specified pathogen-free grade C57BL/6J mice were randomly divided into 6 groups, 10 mice in each group. The COPD mice model was induced by cigarette smoke extract combined with lipopolysaccharide, and the mice in each group were given corresponding drugs. Lung function was assessed in all mice. Lung tissues were stained with hematoxylin-eosin, Masson, and periodic acid-Schiff stains, and serum levels of interleukin (IL)-8 and tumor necrosis factor (TNF)-α were detected using an ELISA. Further, serum and lung tissue levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were detected by colorimetric assay. Network pharmacology and molecular docking were used to predict signaling pathways, which were validated by Western blot analysis.

RESULTS

Compared with the COPD group, the mice in each dosing group of CR exhibited significant reductions in serum IL-8 and TNF-α levels, serum and lung tissue MDA levels, and pathological lung tissue damage, alongside elevations in lung function and SOD levels (p < 0.01). Western blot analysis also indicated significant downregulation of p-p65/p65 and p-IκB-α/IκB-α protein expression, alongside significant upregulation of Nrf2 protein expression in the lung tissues of mice treated with CR (p < 0.01).

CONCLUSION

In summary, CR effectively enhances lung function, minimizes lung tissue damage, and inhibits inflammation and oxidative stress in mice with COPD. Additionally, these findings suggest that inhibition of the Nrf2/NF-κB axis may be a key mechanism of action of CR in the alleviation of COPD.

COX-2/sEH-Mediated Macrophage Activation Is a Target for Pulmonary Protection in Mouse Models of Chronic Obstructive Pulmonary Disease

Effective inhibition of macrophage activation is critical for resolving inflammation and restoring pulmonary function in patients with chronic obstructive pulmonary disease (COPD). In this study, we identified the dual-enhanced cyclooxygenase-2 (COX-2)/soluble epoxide hydrolase (sEH) as a novel regulator of macrophage activation in COPD. Both COX-2 and sEH were found to be increased in patients and mice with COPD and in macrophages exposed to cigarette smoke extract. Pharmacological reduction of the COX-2 and sEH by 4-(5-phenyl-3-{3-[3-(4-trifluoromethylphenyl)-ureido]-propyl}-pyrazol-1-yl)-benzenesulfonamide (PTUPB) effectively prevented macrophage activation, downregulated inflammation-related genes, and reduced lung injury, thereby improving respiratory function in a mouse model of COPD induced by cigarette smoke and lipopolysaccharide. Mechanistically, enhanced COX-2/sEH triggered the activation of the NACHT, LRR, and PYD domains-containing protein 3 inflammasome, leading to the cleavage of pro-IL-1β into its active form in macrophages and amplifying inflammatory responses. These findings demonstrate that targeting COX-2/sEH-mediated macrophage activation may be a promising therapeutic strategy for COPD. Importantly, our data support the potential use of the dual COX-2 and sEH inhibitor PTUPB as a therapeutic drug for the treatment of COPD.

Nanocurcumin supplementation improves pulmonary function in severe COPD patients: A randomized, double blind, and placebo-controlled clinical trial

Considering the anti-inflammatory properties of curcumin, the present study was designed to investigate the effect of nano-curcumin on respiratory indices and interleukin-6 (IL-6) levels in severe chronic obstructive pulmonary disease (COPD) patients as a common pulmonary disease causing restricted airflow and breathing problems. In the current double-blind placebo-controlled randomized clinical trial study, 60 patients with stages 3 and 4 COPD were randomly assigned into 80 mg nano-curcumin (n = 30) and placebo groups (n = 30) for 3 months. The effect of nano-curcumin on pulmonary function was evaluated by the first second of forced expiration (FEV1) to the full, forced vital capacity (FVC) ratio. IL-6 serum level, blood pressure, and anthropometric indices were also measured. Nano-curcumin supplementation led to a significant decrease in IL-6 level (p < 0.001) and an increase in FEV1 (p < 0.001), FVC (p = 0.003), and FEV1/FVC (p < 0.001) compared to placebo at the endpoint. Nano-curcumin had a significantly increasing effect on weight and body mass index compared to the placebo group (PANCOVA adjusted for baseline values  = 0.042). There was a meaningful improvement in systolic blood pressure in the nano-curcumin group compared to the placebo group (PANCOVA adjusted for baseline values  = 0.026). There was no significant difference between the two groups in terms of waist circumference, waist-to-hip ratio, and diastolic blood pressure (PANCOVA adjusted for baseline values >0.05). Nano-curcumin supplement seems to have favorable effects on inflammation status and respiratory indices of patients with severe COPD.

Evaluating the Therapeutic Potential of Curcumin and Synthetic Derivatives: A Computational Approach to Anti-Obesity Treatments

Natural compounds such as curcumin, a polyphenolic compound derived from the rhizome of turmeric, have gathered remarkable scientific interest due to their diverse metabolic benefits including anti-obesity potential. However, curcumin faces challenges stemming from its unfavorable pharmacokinetic profile. To address this issue, synthetic curcumin derivatives aimed at enhancing the biological efficacy of curcumin have previously been developed. In silico modelling techniques have gained significant recognition in screening synthetic compounds as drug candidates. Therefore, the primary objective of this study was to assess the pharmacokinetic and pharmacodynamic characteristics of three synthetic derivatives of curcumin. This evaluation was conducted in comparison to curcumin, with a specific emphasis on examining their impact on adipogenesis, inflammation, and lipid metabolism as potential therapeutic targets of obesity mechanisms. In this study, predictive toxicity screening confirmed the safety of curcumin, with the curcumin derivatives demonstrating a safe profile based on their LD50 values. The synthetic curcumin derivative 1A8 exhibited inactivity across all selected toxicity endpoints. Furthermore, these compounds were deemed viable candidate drugs as they adhered to Lipinski's rules and exhibited favorable metabolic profiles. Molecular docking studies revealed that both curcumin and its synthetic derivatives exhibited favorable binding scores, whilst molecular dynamic simulations showed stable binding with peroxisome proliferator-activated receptor gamma (PPARγ), csyclooxygenase-2 (COX2), and fatty acid synthase (FAS) proteins. The binding free energy calculations indicated that curcumin displayed potential as a strong regulator of PPARγ (-60.2 ± 0.4 kcal/mol) and FAS (-37.9 ± 0.3 kcal/mol), whereas 1A8 demonstrated robust binding affinity with COX2 (-64.9 ± 0.2 kcal/mol). In conclusion, the results from this study suggest that the three synthetic curcumin derivatives have similar molecular interactions to curcumin with selected biological targets. However, in vitro and in vivo experimental studies are recommended to validate these findings.

The protective effects of curcumin against cigarette smoke-induced toxicity: A comprehensive review

Cigarette smoking (CS) is a crucial modifiable risk of developing several human diseases and cancers. It causes lung, bladder, breast, and esophageal cancers, respiratory disorders, as well as cardiovascular and metabolic diseases. Because of these adverse health effects, continual efforts to decrease the prevalence and toxicity of CS are imperative. Until the past decades, the impacts of natural compounds have been under investigation on the harmful effects of CS. Turmeric (Curcuma longa), a rhizomatous herbaceous perennial plant that belongs to the Zingiberaceae family, is the main source of curcumin. This review is an attempt to find out the current knowledge on CS's harmful effects and protective potential of curcumin in the pulmonary, liver, brain, gastrointestinal, and testis organs. According to the present review, simultaneous consumption of curcumin and CS can attenuate CS toxicities including chronic obstructive pulmonary disease, gastrointestinal toxicity, metabolic diseases, testis injury, and neurotoxicity. Moreover, curcumin suppresses carcinogenesis in the skin, liver, lungs, breast, colon, and stomach. Curcumin mediates these protective effects through antioxidant, anti-inflammatory, anti-apoptotic, and anti-carcinogenicity properties.

Therapeutic potential of natural products in inflammation: underlying molecular mechanisms, clinical outcomes, technological advances, and future perspectives

Chronic inflammation is a common underlying factor in many major diseases, including heart disease, diabetes, cancer, and autoimmune disorders, and is responsible for up to 60% of all deaths worldwide. Metformin, statins, and corticosteroids, and NSAIDs (non-steroidal anti-inflammatory drugs) are often given as anti-inflammatory pharmaceuticals, however, often have even more debilitating side effects than the illness itself. The natural product-based therapy of inflammation-related diseases has no adverse effects and good beneficial results compared to substitute conventional anti-inflammatory medications. In this review article, we provide a concise overview of present pharmacological treatments, the pathophysiology of inflammation, and the signaling pathways that underlie it. In addition, we focus on the most promising natural products identified as potential anti-inflammatory therapeutic agents. Moreover, preclinical studies and clinical trials evaluating the efficacy of natural products as anti-inflammatory therapeutic agents and their pragmatic applications with promising outcomes are reviewed. In addition, the safety, side effects and technical barriers of natural products are discussed. Furthermore, we also summarized the latest technological advances in the discovery and scientific development of natural products-based medicine.

Neutralizing tumor-related inflammation and reprogramming of cancer-associated fibroblasts by Curcumin in breast cancer therapy

Tumor-associated inflammation plays a vital role in cancer progression. Among the various stromal cells, cancer-associated fibroblasts are promising targets for cancer therapy. Several reports have indicated potent anti-inflammatory effects attributed to Curcumin. This study aimed to investigate whether inhibiting the inflammatory function of cancer-associated fibroblasts (CAFs) with Curcumin can restore anticancer immune responses. CAFs were isolated from breast cancer tissues, treated with Curcumin, and co-cultured with patients' PBMCs to evaluate gene expression and cytokine production alterations. Blood and breast tumor tissue samples were obtained from 12 breast cancer patients with stage II/III invasive ductal carcinoma. Fibroblast Activation Protein (FAP) + CAFs were extracted from tumor tissue, treated with 10 μM Curcumin, and co-cultured with corresponding PBMCs. The expression of smooth muscle actin-alpha (α-SMA), Cyclooxygenase-2(COX-2), production of PGE2, and immune cell cytokines were evaluated using Real-Time PCR and ELISA, respectively. Analyzes showed that treatment with Curcumin decreased the expression of genes α-SMA and COX-2 and the production of PGE2 in CAFs. In PBMCs co-cultured with Curcumin-treated CAFs, the expression of FoxP3 decreased along with the production of TGF-β, IL-10, and IL-4. An increase in IFN-γ production was observed that followed by increased T-bet expression. According to our results, Curcumin could reprogram the pro-tumor phenotype of CAFs and increase the anti-tumor phenotype in PBMCs. Thus, CAFs, as a component of the tumor microenvironment, are a suitable target for combination immunotherapies of breast cancer.

Immune Diseases Associated with Aging: Molecular Mechanisms and Treatment Strategies

Aging is associated with a decline in immune function, thereby causing an increased susceptibility to various diseases. Herein, we review immune diseases associated with aging, focusing on tumors, atherosclerosis, and immunodeficiency disorders. The molecular mechanisms underlying these conditions are discussed, highlighting telomere shortening, tissue inflammation, and altered signaling pathways, e.g., the mammalian target of the rapamycin (mTOR) pathway, as key contributors to immune dysfunction. The role of the senescence-associated secretory phenotype in driving chronic tissue inflammation and disruption has been examined. Our review underscores the significance of targeting tissue inflammation and immunomodulation for treating immune disorders. In addition, anti-inflammatory medications, including corticosteroids and nonsteroidal anti-inflammatory drugs, and novel approaches, e.g., probiotics and polyphenols, are discussed. Immunotherapy, particularly immune checkpoint inhibitor therapy and adoptive T-cell therapy, has been explored for its potential to enhance immune responses in older populations. A comprehensive analysis of immune disorders associated with aging and underlying molecular mechanisms provides insights into potential treatment strategies to alleviate the burden of these conditions in the aging population. The interplay among immune dysfunction, chronic tissue inflammation, and innovative therapeutic approaches highlights the importance of elucidating these complex processes to develop effective interventions to improve the quality of life in older adults.

L-Arginine, as an essential amino acid, is a potential substitute for treating COPD via regulation of ROS/NLRP3/NF-κB signaling pathway

BACKGROUNDS

Chronic obstructive pulmonary disease (COPD) is a frequent and common disease in clinical respiratory medicine and its mechanism is unclear. The purpose of this study was to find the new biomarkers of COPD and elucidate its role in the pathogenesis of COPD. Analysis of metabolites in plasma of COPD patients were performed by ultra-high performance liquid chromatography (UPLC) and quadrupole time-of-flight mass spectrometry (TOF-MS). The differential metabolites were analyzed and identified by multivariate analysis between COPD patients and healthy people. The role and mechanisms of the differential biomarkers in COPD were verified with COPD rats, arginosuccinate synthetase 1 (ASS-l) KO mice and bronchial epithelial cells (BECs). Meanwhile, whether the differential biomarkers can be the potential treatment targets for COPD was also investigated. 85 differentials metabolites were identified between COPD patients and healthy people by metabonomic.

RESULTS

L-Arginine (LA) was the most obvious differential metabolite among the 85 metabolites. Compare with healthy people, the level of LA was markedly decreased in serum of COPD patients. It was found that LA had protective effects on COPD with in vivo and in vitro experiments. Silencing Ass-1, which regulates LA metabolism, and α-methy-DL-aspartic (NHLA), an Ass-1 inhibitor, canceled the protective effect of LA on COPD. The mechanism of LA in COPD was related to the inhibition of ROS/NLRP3/NF-κB signaling pathway. It was also found that exogenous LA significantly improved COPD via regulation of ROS/NLRP3/NF-κB signaling pathway. L-Arginine (LA) as a key metabolic marker is identified in COPD patients and has a protective effect on COPD via regulation of ROS/NLRP3/NF-κB signaling pathway.

CONCLUSION

LA may be a novel target for the treatment of COPD and also a potential substitute for treating COPD.

Advances in traditional Chinese medicine for the treatment of chronic obstructive pulmonary disease

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death globally and thus imposes heavy economic burden on patients, their families, and society. Furthermore, COPD seriously affects the quality of life of patients. The concept of "overall regulation" of traditional Chinese medicine (TCM) plays an important role in the prevention and treatment of COPD.

AIM OF THE STUDY

The objective of this review is to summarize the TCM theories, experimental methods, TCM extracts, active TCM ingredients, and TCM formulas for the treatment of COPD and reveal the effects and mechanisms of TCM treatments on COPD.

MATERIALS AND METHODS

This article reviewed literature on TCM-based treatments for COPD reported from 2016 to 2021. Relevant scientific studies were obtained from databases that included PubMed, China National Knowledge Infrastructure, Web of Science, Google Scholar, The Plant List, ScienceDirect, and SciFinder.

RESULTS

This review summarized TCM-based theory, experimental methods, active ingredients, and potential toxicities, the effects of TCM extracts and formulations, and their mechanisms for the treatment of COPD. Most investigators have used in vivo models of cigarette smoke combined with lipopolysaccharide induction in rats and in vitro models of cigarette smoke extract induction. The active ingredients of TCM used for the treatment of COPD in relevant studies were triterpenoids, flavonoids, phenolics, quinones, glycosides, and alkaloids. TCMs commonly used in the treatment of COPD include antipyretic drugs, tonic medicines, anticough medications, and asthma medications. TCM can treat COPD by suppressing inflammation, reducing oxidative stress, inhibiting apoptosis, and improving airway remodeling.

CONCLUSIONS

This review enriches the theory of COPD treatments based on TCM, established the clinical significance and development prospects of TCM-based COPD treatments, and provided the necessary theoretical support for the further development of TCM resources for the treatment of COPD.

Curcumin and Its Derivatives as Potential Antimalarial and Anti-Inflammatory Agents: A Review on Structure-Activity Relationship and Mechanism of Action

Curcumin, one of the major ingredients of turmeric (Curcuma longa), has been widely reported for its diverse bioactivities, including against malaria and inflammatory-related diseases. However, curcumin's low bioavailability limits its potential as an antimalarial and anti-inflammatory agent. Therefore, research on the design and synthesis of novel curcumin derivatives is being actively pursued to improve the pharmacokinetic profile and efficacy of curcumin. This review discusses the antimalarial and anti-inflammatory activities and the structure-activity relationship (SAR), as well as the mechanisms of action of curcumin and its derivatives in malarial treatment. This review provides information on the identification of the methoxy phenyl group responsible for the antimalarial activity and the potential sites and functional groups of curcumin for structural modification to improve its antimalarial and anti-inflammatory actions, as well as potential molecular targets of curcumin derivatives in the context of malaria and inflammation.

EPC-exosomal miR-26a-5p improves airway remodeling in COPD by inhibiting ferroptosis of bronchial epithelial cells via PTGS2/PGE2 signaling pathway

We aimed to investigate whether exosomes (Exo) affected chronic obstructive pulmonary disease (COPD) by influencing ferroptosis of bronchial epithelial cells (BECs) and the mechanisms involved. Here we took the peripheral blood samples of normal subjects and COPD patients, extracted and identified endothelial progenitor cells (EPCs) and EPC-Exo. An animal model of COPD was established. Then human BECs were taken and treated with cigarette smoke extract (CSE) for 24 h to construct a COPD cell model. Next, we screened differentially expressed ferroptosis-related genes in COPD patients by bioinformatics. Bioinformatics predicted the miRNA targeting PTGS2. Then, the mechanism of action of miR-26a-5p and Exo-miR-26a-5p was investigated in vitro. We successfully isolated and identified EPC and Exo. In vitro, EPC alleviated CSE-induced ferroptosis in BECs by transporting Exo. In vivo, Exo alleviated cigarette smoke-induced ferroptosis and airway remodeling in mice. Through further validation, we found that CSE-induced ferroptosis promoted the epithelial-mesenchymal transition (EMT) of BECs. Bioinformatics analysis and validation showed that PTGS2/PGE2 pathway affected CSE-induced ferroptosis in BECs. Meanwhile, miR-26a-5p targeting PTGS2 affected CSE-induced ferroptosis in BECs. Additionally, we found that miR-26a-5p affected CSE-induced BECs EMT. Exo-miR-26a-5p alleviated CSE-induced ferroptosis and EMT. In conclusion, EPC-exosomal miR-26a-5p improved airway remodeling in COPD by inhibiting ferroptosis of BECs via the PTGS2/PGE2 pathway.

Paraquat-induced systemic inflammation and oxidative stress in rats improved by Curcuma longa ethanolic extract, curcumin and a PPAR agonist

The effect of Curcuma longa (Cl) ethanolic extract, nano-curcumin (Cu) and a PPARγ activator, pioglitazone on inhaled paraquat (PQ)-induced systemic inflammation and oxidative stress was examined in the present study. Control rats were exposed to normal saline and PQ groups to 27 and 54 mg/m³ (PQ-L and PQ-H) aerosols. Nine other PQ-H groups were treated with Curcuma longa (Cl, 150 and 600 mg/kg/day), nano-curcumin (Cu, 2 and 8 mg/kg/day), pioglitazone (Pio, 5 and 10 mg/kg), low dose of Pio + Cl and Cu and dexamethasone (0.03 mg/kg/day) for 16 days after PQ exposure period (n = 8). Total and differential WBC counts, malondialdehyde (MDA) and TNF-α levels were increased but thiol, catalase (CAT), superoxide dismutase (SOD), IL-10 and IFN-γ levels were decreased in the blood in the both PQ groups (p < 0.05 to p < 0.001). Treatment with Dexa and both doses of Cl, Cu, and Pio improved all measured variables compared to the PQ-H group (p < 0.05 to p < 0.001). The improvements of most variables in the treated group with low dose of Pio + Cl and Cu were higher than the effects of three agents alone. Systemic inflammation and oxidative stress induced by inhaled PQ were improved by Cl, Cu and Pio. In addition, a synergic effect between Pio with those of Cl and Cu was shown, suggesting PPARγ mediated effects of the plant and its derivative Cu.

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.

Curcumin effects on chronic obstructive pulmonary disease: A systematic review

Introduction

Chronic obstructive pulmonary disease (COPD) is a common disease of the lungs known as the third reason for death worldwide. Frequent COPD exacerbations compel health care workers to apply interventions that are not adverse effect free. Accordingly, adding or replacing Curcumin, a natural meal flavoring, may indicate advantages in this era by its antiproliferative and anti-inflammatory effects.

Methods

The PRISMA checklist was employed for the systematic review study. On June 3, 2022, PubMed/Medline, Scopus, and Web of Science were searched for studies associated with COPD and Curcumin in the last 10 years. Duplicate or non-English publications and articles with irrelevant titles and abstracts were excluded. Also, preprints, reviews, short communications, editorials, letters to the editor, comments, conference abstracts, and conference papers were not included.

Results

Overall, 4288 publications were found eligible, after the screening, 9 articles were finally included. Among them, one, four, and four in vitro, in vivo, and both in vivo and in vitro research exist respectively. According to the investigations, Curcumin can inhibit alveolar epithelial thickness and proliferation, lessen the inflammatory response, remodel the airway, produce ROS, alleviate airway inflammation, hinder emphysema and prevent ischemic complications.

Conclusion

Consequently, the findings of the current review demonstrate that Curcumin's modulatory effects on oxidative stress, cell viability, and gene expression could be helpful in COPD management. However, for data confirmation, further randomized clinical trials are required.

A comparative study of effects of curcumin and its nanoparticles on the growth, immunity and heat stress resistance of Nile tilapia (Oreochromis niloticus)

This study evaluated the effects of dietary supplementation with free- or nano-curcumin on the growth performance, immune status and heat stress resistance of Nile tilapia (Oreochromis niloticus). Seven isonitrogenous (28% protein) and isocaloric (445 kcal/100 g DM) diets were prepared. Six diets were supplemented with three levels of nano-curcumin (50 (CN50), 100 (CN100), 200 (CN200) mg kg^-1 diet) or free-curcumin (50 (C50), 100 (C100), 200 (C200) mg kg^-1 diet), and the control diet was left without an additive (CON). Fish (13.54 ± 0.32 g) (mean ± SD) fed the experimental diets for 65 days. Following the feeding trial, the fish were exposed to the acute heat stress by gradually raising the water temperature from 25 to 40 °C within 3 h. The fish were then exposed to 40 °C for 4 h. Results revealed the superiority of nano-curcumin over its free-form in enhancing the growth performance, with the highest results obtained at CN100, followed by CN200. Only heat stress, not the experimental diets, increased the platelets, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), leukocytes and neutrophils count, while lymphocytes decreased. The CN50 and CN100 groups showed lower activity of liver enzymes (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) than the other treatments, while C200 gave the highest activity of these enzymes. The highest immunoglobulin (IgM) levels were detected in CN100, CN200, C100 and C200, followed by CN50. The C200 group showed higher levels of complement 3 and complement 4 (C3 and C4, respectively) than the other treatments. The C50 and CON groups gave the lowest values of IgM, C3 and C4. Cortisol levels were significantly lower in the CN50 and CN100 groups compared to the other groups. After the heat stress, ALT, AST, IgM, C3, C4, cortisol and glucose increased. Thus, nano-curcumin is more effective than its free-form in enhancing the resistance to heat stress, inducing innate immunity, lowering the stress indicators and promoting growth performance of Nile tilapia with the best concentration at 100 mg kg^-1 diet.

Curcumin Ameliorates Particulate Matter-Induced Pulmonary Injury through Bimodal Regulation of Macrophage Inflammation via NF-κB and Nrf2

The direct effects of particulate matter (PM) on lung injury and its specific molecular mechanisms are unclear. However, experimental evidence has shown that oxidative stress-mediated inflammation in macrophages is the main pathological outcome of PM exposure. Curcumin has been reported to protect organs against the disturbance of homeostasis caused by various toxic agents through anti-inflammatory and antioxidative effects. However, the protective action of curcumin against PM-induced pulmonary inflammation and the underlying mechanism have not been thoroughly investigated. In this study, we established a PM-induced pulmonary inflammation mouse model using the intratracheal instillation method to investigate the protective ability of curcumin against PM-induced pulmonary inflammation. Compared to the mice treated with PM only, the curcumin-treated mice showed alleviated alveolar damage, decreased immune cell infiltration, and reduced proinflammatory cytokine production in both lung tissue and BALF. To evaluate the underlying mechanism, the mouse macrophage cell line RAW264.7 was used. Pretreatment with curcumin prevented the production of PM-induced proinflammatory cytokines by deactivating NF-κB through the suppression of MAPK signaling pathways. Furthermore, curcumin appears to attenuate PM-induced oxidative stress through the activation of Nrf2 and downstream antioxidant signaling. Our findings demonstrate that curcumin protects against PM-induced lung injury by suppressing oxidative stress and inflammatory activation in macrophages.

Decreased Sphingosine Due to Down-Regulation of Acid Ceramidase Expression in Airway of Bronchiectasis Patients: A Potential Contributor to Pseudomonas aeruginosa Infection

Purpose

To assess the metabolites associated with Pseudomonas aeruginosa infection by analyzing the microbial diversity and metabolomics in lower respiratory tract of bronchiectasis patients and to explore the therapeutic approaches for Pseudomonas aeruginosa infection.

Methods

Bronchoalveolar lavage fluid samples from bronchiectasis patients and controls were analyzed by 16S rRNA and ITS sequencing, and metabolomic analysis was performed by liquid chromatography/mass spectrometry. A co-culture model of air-liquid interface cultured human bronchial epithelial cell with Pseudomonas aeruginosa was constructed to verify the correlation between sphingosine metabolism, acid ceramidase expression, and Pseudomonas aeruginosa infection.

Results

After screening, 54 bronchiectasis patients and 12 healthy controls were included. Sphingosine levels in bronchoalveolar lavage fluid were positively correlated with lower respiratory tract microbial diversity and negatively correlated with the abundance of Pseudomonas spp. Moreover, sphingosine levels in bronchoalveolar lavage fluid and acid ceramidase expression levels in lung tissue specimens were significantly lower in bronchiectasis patients than in healthy controls. Sphingosine levels and acid ceramidase expression levels were also significantly lower in bronchiectasis patients with positive Pseudomonas aeruginosa cultures than in bronchiectasis patients without Pseudomonas aeruginosa infection. Acid ceramidase expression in air-liquid interface cultured human bronchial epithelial cell had significantly increased after 6 h of Pseudomonas aeruginosa infection, while it had decreased significantly after 24 h of infection. In vitro experiments showed that sphingosine had a bactericidal effect on Pseudomonas aeruginosa by directly disrupting its cell wall and cell membrane. Furthermore, adherence of Pseudomonas aeruginosa on bronchial epithelial cells was significantly reduced after sphingosine supplementation.

Conclusion

Down-regulation of acid ceramidase expression in airway epithelial cells of bronchiectasis patients leads to insufficient metabolism of sphingosine, which has a bactericidal effect, and consequently weakens the clearance of Pseudomonas aeruginosa; thus, a vicious circle is formed. Exogenous supplementation with sphingosine aids bronchial epithelial cells in resisting Pseudomonas aeruginosa infection.

The Role and Mechanisms of Traditional Chinese Medicine for Airway Inflammation and Remodeling in Asthma: Overview and Progress

Asthma as an individual disease has blighted human health for thousands of years and is still a vital global health challenge at present. Though getting much progress in the utilization of antibiotics, mucolytics, and especially the combination of inhaled corticosteroids (ICS) and long-acting β-agonists (LABA), we are confused about the management of asthmatic airway inflammation and remodeling, which directly threatens the quality of life for chronic patients. The blind addition of ICS will not benefit the remission of cough, wheeze, or sputum, but to increase the risk of side effects. Thus, it is necessary to explore an effective therapy to modulate asthmatic inflammation and airway remodeling. Traditional Chinese Medicine (TCM) has justified its anti-asthma effect in clinical practice but its underlying mechanism and specific role in asthma are still unknown. Some animal studies demonstrated that the classic formula, direct exacts, and natural compounds isolated from TCM could significantly alleviate airway structural alterations and exhibit the anti-inflammatory effects. By investigating these findings and data, we will discuss the possible pathomechanism underlined airway inflammation and remodeling in asthma and the unique role of TCM in the treatment of asthma through regulating different signaling pathways.

Granulocyte colony-stimulating factor protected against brain injury in a rat cerebral hemorrhage model by modulating inflammation

Granulocyte colony-stimulating factor (G-CSF) has been reported to exert a protective effect against secondary brain damage, but the underlying mechanisms remain unknown. We explored the ability of G-CSF to protect the brain from injury in a rat autologous blood-induced model of intracerebral hemorrhage (ICH), with a special focus on the anti-inflammation effect. An ICH was induced in 8-week-old male rats by an infusion of autologous blood, and the rats were then randomly assigned to five treatment groups: sham, ICH, and ICH+ low-dose (25 µg/kg), middle-dose (50 µg/kg), and high-dose (75 µg/kg) G-CSF. We then evaluated the levels of brain inflammation-related genes and proteins. The levels of tumor-necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) mRNA increased between days 1 and 14 post-ICH, with the highest expression on day 3. These changes were rectified by G-CSF in a dose-dependent manner. At day 3 post-injury, an elevation of the nuclear factor-kappa B (NF-κB) p65 protein level and a reduction of the inhibitor of NF-κB alpha (IκBα) protein level were observed; G-CSF treatment exerted a beneficial effect on both protein expressions. The expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins were increased; these changes were rectified by the highest dose of G-CSF. The brain-protecting effects of G-CSF are likely to be attributable, at least in part, to attenuation of the TNF-α, IL-6, iNOS, and COX-2 expressions induced by NF-κB activation in the brain tissues of this autologous blood-induced ICH rat model.

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.

Verapamil attenuates oxidative stress and inflammatory responses in cigarette smoke (CS)-induced murine models of acute lung injury and CSE-stimulated RAW 264.7 macrophages via inhibiting the NF-κB pathway

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), severe form of ALI, are characterized by overwhelming of lung inflammation, and no treatment is currently available to treat ALI/ARDS. Cigarette smoke (CS) is one of the prime causes to induce ALI/ARDS via oxidative stress. Despite extensive research, no appropriate therapy is currently available to treat ALI/ARDS. Hence, new potential approaches are needed to treat ALI/ARDS. Consequently, this project was designed to explore the protective effects of verapamil against CS-induced ALI by in vivo and in vitro method. In vivo data obtained from respiratory mechanics, pulmonary morphometric analyses and lung histopathology revealed that verapamil dose-dependently and strikingly decreased the lung weight coefficient, attenuated the albumin exudation into lungs, minimized the infiltration of macrophages and neutrophils into lungs, reduced the pro-inflammatory cytokines (tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and keratinocyte chemoattractant (KC)) production, and improved the hypoxemia and lung histopathological changes. Similarly, verapamil also reduced the production of TNF-α, IL-6 and KC from cigarette smoke extract (CSE)-stimulated RAW 264.7 macrophage. Importantly, verapamil dose-dependently and remarkably suppressed the CS-induced oxidative stress via not only reducing the myeloperoxidase (MPO) activity of lungs, total oxidative stress (TOS) and malondialdehyde (MDA) content in the lungs and supernatant of RAW 264.7 macrophage but also improving total antioxidant capacity (TAC) and superoxide dismutase (SOD) production. Finally, verapamil strikingly decreased the NF-κB expression both in in vivo and in vitro models. Hence, verapamil has positive therapeutic effects against CS-induced ALI via suppressing uncontrolled inflammatory response, oxidative stress and NF-κB p65 signaling.

Potential Natural Small Molecular Compounds for the Treatment of Chronic Obstructive Pulmonary Disease: An Overview

Chronic obstructive pulmonary disease (COPD) is one of the major diseases threatening human life and health. According to the report released by the World Health Organization (WHO) in 2020, COPD has become the third leading cause of death in the world, featuring a sustainable growth of incidence rate as well as population age. The purpose of this review focuses on the advancement of bioactive natural compounds, such as baicalin, quercetin, resveratrol, and curcumin, which demonstrate promising therapeutic/interventional effects on CODP in vitro and in vivo. Information emphasizing on COPD was systematically collected from several authoritative internet databases including Web of Science, PubMed, Elsevier, Wiley Online Library, and Europe PMC, with a combination of keywords containing “COPD” and “natural small molecular compounds”. The new evidence indicated that these valuable molecules featured unique functions in the treatment of COPD through various biological processes such as anti-inflammatory, anti-oxidant, anti-apoptosis, and anti-airway fibrosis. Moreover, we found that the promising effects of these natural compounds on COPD were mainly achieved through JAK3/STAT3/NF-κB and MAPK inflammatory signaling pathways, Nrf2 oxidative stress signaling pathway, and TGF-β1/Smad 2/3 fibrosis signaling pathway, which referenced to multiple targets like TNF-α, IL-6, IL-8, TIMP-1, MMP, AKT, JAK3, IKK, PI3K, HO-1, MAPK, P38, ERK, etc. Current challenges and future directions in this promising field are also discussed at the end of this review. For the convenience of the readers, this review is divided into ten parts according to the structures of potential natural small molecular compounds. We hope that this review brings a quick look and provides some inspiration for the research of COPD.

Vitamin E relieves chronic obstructive pulmonary disease by inhibiting COX2-mediated p-STAT3 nuclear translocation through the EGFR/MAPK signaling pathway

Patients with chronic obstructive pulmonary disease (COPD) are characterized by an imbalance between oxidant enzymes and antioxidant enzymes. In the present study, we explored the protective effect of vitamin E on COPD and the underlying mechanisms. Targets of vitamin E were predicted by bioinformatics analysis. After establishing cigarette smoke (CS)-induced COPD rats, the expression levels of epidermal growth factor receptor (EGFR), cyclooxygenase 2 (COX2), and transcriptional activity of signal transducer and activator of transcription 3 (STAT3) were measured. Additionally, the effects of vitamin E on CS-induced COPD were explored by assessing inflammation, the reactive oxygen species (ROS), the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA), viability of human bronchial epithelioid (HBE) cells, and the expression of EGFR/MAPK pathway-related factors after loss- and gain- function assays. Vitamin E alleviated COPD. Vitamin E inhibited MAPK signaling pathway through decreasing EGFR expression. Additionally, vitamin E suppressed CS-induced HBE cell damage. Functionally, vitamin E attenuated CS-induced inflammation, apoptosis, and ROS by inhibiting the EGFR/MAPK axis, thereby inhibiting COX2-mediated p-STAT3 nuclear translocation. Moreover, overexpression of COX2 attenuated the protective effect of vitamin E on COPD rats. The present study shows that vitamin E inhibits the expression of COX2 by negatively regulating the EGFR/MAPK pathway, thereby inhibiting the translocation of phosphorylated STAT3 to the nucleus and relieving COPD.

Advances in cGAS-STING Signaling Pathway and Diseases

Pathogens can produce conserved pathogen-associated molecular patterns (PAMPs) after invading the body, which can be specifically recognized by host pattern recognition receptors (PRRs). In recent years, it has been found that cytoplasmic DNA receptors recognize exogenous DNA inducing activation of interferon 1 (IFN1), which is a rapid advance in various research areas. The cyclic GMP–AMP synthase (cGAS) stimulator of interferon gene (STING) signaling pathway is a critical natural immune pathway in cells. Early studies revealed that it plays a crucial regulatory role in pathogen infection and tumor, and it is associated with various human autoimmune diseases. Recently studies have found that activation of cGAS-STING signaling pathway is related to different organ injuries. The present review elaborates on the regulation of the cGAS-STING signaling pathway and its role in various diseases, aiming to provide a theoretical basis for immunotherapy targeting this pathway.

Role and mechanism of miR-181a-5p in mice with chronic obstructive pulmonary disease by regulating HMGB1 and the NF-κB pathway

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease. This study explored the mechanism of miR-181a-5p in the inflammatory response in COPD mice. COPD mouse models were established by cigarette smoke (CS) exposure following pretreatment with recombinant adeno-associated virus (rAAv)-miR-181a-5p, si-HMGB1 (high mobility group box 1), and NF-κB pathway inhibitor PDTC, respectively. Pathological changes of lung tissues were determined by HE staining. BALF was collected to count total cells, neutrophils and lymphocytes using a Countess II automatic cell counter. Expressions of NE and inflammatory factors (TNF-α, IL-6, IL-8 and IFN-γ) were detected by ELISA. Binding relationship between miR-181a-5p and HMGB1 was predicted on Starbase (http://starbase.sysu.edu.cn/index.php) and validated by dual-luciferase assay. miR-181a-5p expression was detected by RT-qPCR, and expressions of HMGB1, IκBα, p-IκBα were detected by Western blot. The expression level of miR-181a-5p was lower in lung tissues. miR-181a-5p overexpression alleviated inflammatory response and pathological changes of lung tissues in COPD mice, with decreased pulmonary inflammation scores, total cells, neutrophils, and lymphocytes and expressions of NE and inflammatory factors. HMGB1 expression level was increased in COPD mice. miR-181a-5p targeted HMGB1. si-HMGB1 relieved inflammatory responses in COPD mice. NF-κB was activated in COPD mice, evidenced by degraded IκBα and increased p-IκBα level. si-HMGB1 significantly restrained the activation of NF-κB pathway. Briefly, miR-181a-5p targets HMGB1 to inhibit the NF-κB pathway, thus alleviating the inflammatory response in COPD mice.

Curcumin: Biological Activities and Modern Pharmaceutical Forms

Curcumin (1,7-bis-(4-hydroxy-3-methoxyphenyl)-hepta-1,6-diene-3,5-dione) is a natural lipophilic polyphenol that exhibits significant pharmacological effects in vitro and in vivo through various mechanisms of action. Numerous studies have identified and characterised the pharmacokinetic, pharmacodynamic, and clinical properties of curcumin. Curcumin has an anti-inflammatory, antioxidative, antinociceptive, antiparasitic, antimalarial effect, and it is used as a wound-healing agent. However, poor curcumin absorption in the small intestine, fast metabolism, and fast systemic elimination cause poor bioavailability of curcumin in human beings. In order to overcome these problems, a number of curcumin formulations have been developed. The aim of this paper is to provide an overview of recent research in biological and pharmaceutical aspects of curcumin, methods of sample preparation for its isolation (Soxhlet extraction, ultrasound extraction, pressurised fluid extraction, microwave extraction, enzyme-assisted aided extraction), analytical methods (FTIR, NIR, FT-Raman, UV-VIS, NMR, XRD, DSC, TLC, HPLC, HPTLC, LC-MS, UPLC/Q-TOF-MS) for identification and quantification of curcumin in different matrices, and different techniques for developing formulations. The optimal sample preparation and use of an appropriate analytical method will significantly improve the evaluation of formulations and the biological activity of curcumin.

Curcumin alleviated lipopolysaccharide-evoked H9c2 cells damage via suppression of intercellular adhesion molecule 1/CD40/NF-κB signaling

BACKGROUND

Curcumin has been reported to have many benefits, including anti-inflammatory, anti-cancer, and so on. In this research, we aimed to investigate the function of curcumin on lipopolysaccharide (LPS)-injured H9c2 cells.

METHODS

H9c2 cells stimulated by LPS mimic the in vitro model of myocarditis injury. Comparative Toxicogenomics Database (CTD) was applied to detect the genes associated with curcumin. GEO database was used to analyze Intercellular Adhesion Molecule 1 (ICAM1) and CD40 expression in myocarditis patients. KEGG enrichment analysis was employed to investigate the meaningful pathways related to differentially expressed genes. Cell proliferation, apoptosis, expression of ICAM1/CD40/P65- NF-κB, and level of TNF-α, IL-6, and IL-10 were observed by cell counting kit-8, flow cytometry and western blotting assays, ELISA assay, respectively.

RESULTS

After curcumin treatment, the decreased activity of H9c2 cells evoked by LPS was improved. ICAM1 and CD40, which highly expressed in myocarditis patients, were identified as targets of curcumin and negatively regulated by curcumin. Inhibition of ICAM1 or CD40 strengthened the protective effect of curcumin on LPS-evoked H9c2 cells damage, accompanied by increased cell viability and decreased cell apoptosis and inflammation. Additionally, addition of curcumin or depletion of ICAM1/CD40 suppressed p-P65 NF-κB expression.

CONCLUSIONS

Curcumin mitigated LPS-evoked H9c2 cells damage by suppression of ICAM1/CD40/NF-κB, providing a potential molecular mechanism for the clinical application of curcumin.

Nutriepigenomics and chronic obstructive pulmonary disease: potential role of dietary and epigenetics factors in disease development and management

Over recent decades, a number of studies have revealed the possible role of different types of diets, as well as the nutritional elements they are made up of, in the pathogenesis of chronic obstructive pulmonary disease (COPD). To date, dietary factors have been identified to play a role in the prevention of COPD, with evidence from antioxidant nutrients, vitamins, and fiber intake. Additionally, certain dietary patterns such as the Mediterranean diet, together with other Western diets, provide evidence of the influence on COPD development, promoting lung health through nutritional approaches, and giving us an opportunity for intervention. The effect of diet on COPD is conveyed by 3 mechanisms: regulation of inflammation, oxidative stress, and carbon dioxide produced/oxygen intake. Current advances have begun to highlight the possible role of diet in modifying gene expression in certain individuals that predisposes them to COPD through epigenetic modifications. The relation between dietary intake and epigenetic factors has therefore outlined nutriepigenomics as a possible missing link in the relation between environmental exposure to smoke and the appearance of a subsequent chronic bronchial obstruction. This review summarizes the evidence regarding the influence of dietary patterns and nutrients and epigenetic regulatory mechanisms on COPD development and prevention with the aim of encouraging clinical research on the impact of dietary modifications on COPD-related clinical outcomes. This review highlights the importance of proposing and carrying out future studies focused on the modulating effects of certain nutrients on epigenetic changes in patients with specific COPD phenotypes (bronchiectasis, emphysema, asthma/COPD, chronic bronchitis), and their individual responses to cigarette smoking, environmental pollution, or other noxious particles. The objectives of these future studies must be directed to the development of novel therapeutic approaches and personalized management of COPD.

A Novel Curcumin-Based Drug Powder Inhalation Medicine for Chronic Obstructive Pulmonary Disease

The dry powder inhaler is a new form of drug delivery that is widely used as an alternative to traditional drug delivery methods, addressing the shortcomings of traditional drug delivery methods and obtaining better therapeutic results. This mode of delivery is also one of the most rational ways to treat pulmonary diseases such as chronic obstructive pulmonary disease (COPD). Curcumin, a natural polyphenol, has been shown to be effective in the treatment of COPD. In this study, different concentrations of curcumin ethanol solution were spray dried with mannitol as a carrier to obtain dry powder particles with different particle size distribution for the preparation of curcumin dry powder inhaler. The solubility and physicochemical properties were further characterized by differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy. The characterization results showed that the product obtained in the experiment had reasonable particle size distribution and excellent solubility properties, which were positive for the treatment of COPD or other pulmonary diseases.

Randomized, placebo controlled, double blinded pilot superiority phase 2 trial to evaluate the effect of curcumin in moderate to severe asthmatics

Background

Curcumin, a derivative of the spice turmeric, has been adopted by Eastern medicine for centuries as an adjunct to treat several medical conditions (e.g., anorexia and arthritis) because of its well-established anti-inflammatory properties. Studies have shown that the use of curcumin in mice models has led to reduction in several inflammatory markers as well as key inflammatory pathway enzymes. As a result, studies in Western medicine have developed to determine if this recognized benefit can be utilized for patients with inflammatory lung diseases, such as asthma. This study will seek to better understand if curcumin can be used as an adjunctive therapy for improving asthma control of patients with moderate to severe asthma; a finding we hope will allow for a more affordable treatment.

Methods

This study will utilize a randomized, placebo controlled, double blinded pilot superiority phase 2 trial at an outpatient pulmonary clinic in Southern California, USA. Subjects will be receiving Curcumin 1500 mg or matching placebo by mouth twice daily for the study period of 12 weeks. Subjects will be randomized to either a placebo or intervention Curcumin. Subjects will have 6 clinic visits: screening visit, a baseline visit, monthly clinic visits (weeks 4, 8, and 12), at weeks 4, 8, and a follow-up clinic visit or phone-call (week 16). Changes in asthma control test scores, number of days missed from school/work, FEV1 (% predicted), FEV1/FVC ratio, FVC (% predicted), blood eosinophil count, blood total IgE, and FeNO levels will be compared by group over time.

Discussion

The therapeutic effects of curcumin have been studied on a limited basis in asthmatics and has shown mixed results thus far. Our study hopes to further establish the benefits of curcumin, however, there are potential issues that may arise from our study design that we will address within this paper. Moreover, the onset of the COVID-19 pandemic has resulted in safety concerns that have delayed initiation of our study. This study will contribute to existing literature on curcumin’s role in reducing lung inflammation as it presents in asthmatics as well as patients suffering from COVID-19.

Trial registration

This study protocol has been approved by the Institutional Review Board at Loma Linda University Health, (NCT04353310). IND# 145101 Registered April 20th, 2020. https://clinicaltrials.gov/ct2/show/NCT04353310.

Pharmacological properties and underlying mechanisms of curcumin and prospects in medicinal potential

Curcumin, isolated from Curcuma longa L., is a fat-soluble natural compound that can be obtained from ginger plant tuber roots, which accumulative evidences have demonstrated that it can resist viral and microbial infection and has anti-tumor, reduction of blood lipid and blood glucose, antioxidant and removal of free radicals, and is active against numerous disorders various chronic diseases including cardiovascular, pulmonary, neurological and autoimmune diseases. In this article is highlighted the recent evidence of curcuminoids applied in sevral aspects of medical problem particular in COVID-19 pandemics. We have searched several literature databases including MEDLINE (PubMed), EMBASE, the Web of Science, Cochrane Library, Google Scholar, and the ClinicalTrials.gov website via using curcumin and medicinal properties as a keyword. All studies published from the time when the database was established to May 2021 was retrieved. This review article summarizes the growing confirmation for the mechanisms related to curcumin's physiological and pharmacological effects with related target proteins interaction via molecular docking. The purpose is to provide deeper insight and understandings of curcumin's medicinal value in the discovery and development of new drugs. Curcumin could be used in the prevention or therapy of cardiovascular disease, respiratory diseases, cancer, neurodegeneration, infection, and inflammation based on cellular biochemical, physiological regulation, infection suppression and immunomodulation.

Molecular Mechanism of Xixin-Ganjiang Herb Pair Treating Chronic Obstructive Pulmonary Disease-Integrated Network Pharmacology and Molecular Docking

Background

Chronic obstructive pulmonary disease (COPD) is characterized by high morbidity, disability, and mortality, which seriously threatens human life and health. Xixin and Ganjiang are classic herb pairs of Zhongjing Zhang, which are often used to treat COPD in China. However, the substance basis and mechanism of action of Xixin-Ganjiang herb pair (XGHP) in the treatment of COPD remain unclear.

Methods

On the website of TCMSP and the DrugBank, effective compounds and targets of XGHP were found. COPD targets were obtained from GeneCards, DisGeNET, and GEO gene chips. Intersecting these databases resulted in a library of drug targets for COPD. Then, intersection targets were used for protein-protein interaction (PPI) and pathway enrichment analysis. Finally, the binding activity between compounds and core genes was evaluated by molecular docking to verify the expression level of PTGS2 and PPARG in rats.

Results

Twelve effective compounds and 104 core genes were found in the intersection library, and kaempferol, sesamin, β-sitosterol, PTGS2, and PPARG were particularly prominent in the network analysis. A total of 113 pathways were obtained and enrichment of the TNF signaling pathway, IL-17 signaling pathway, and C-type lectin receptor signaling pathway was particularly obvious. Molecular docking indicated that kaempferol, sesamin, and β-sitosterol were closely related to PTGS2 and PPARG and were superior to aminophylline. Key compounds in XGHP could restrict the expression of PTGS2 in the lung tissues of COPD rats and promote the expression of PPARG.

Conclusion

Inhibition of the expression of inflammatory factor PTGS2 and promotion of the expression of PPARG may be an effective target of XGHP in the treatment of COPD.

The Effect of Curcumin Nanoparticles on Cisplatin-Induced Cardiotoxicity in Male Wistar Albino Rats

The cardiotoxicity of chemotherapeutic drugs as cisplatin has become a major issue in recent years. The present study investigates the efficacy of curcumin nanoparticles against the cardiotoxic effects of cisplatin by assessment of oxidative stress parameters, Na+,K+-ATPase, acetylcholinesterase (AchE) and tumor necrosis factor-alpha (TNF-α) in cardiac tissue in addition to serum lactate dehydrogenase (LDH). Rats were divided into three groups: control rats that received saline for 14 days; cisplatin-treated rats that received a single intraperitoneal (i.p.) injection of cisplatin (12 mg/kg) followed by a daily oral administration of saline (0.9%) for 14 days and rats treated with a single i.p. injection of cisplatin (12 mg/kg) followed by a daily oral administration of curcumin nanoparticles (50 mg/kg) for 14 days. Cisplatin resulted in a significant increase in lipid peroxidation, nitric oxide (NO), and TNF-α and a significant decrease in reduced glutathione (GSH) levels and Na+, K+- ATPase activity. Moreover, significant increases in cardiac AchE and serum lactate dehydrogenase activities were recorded. Treatment of cisplatin-injected animals with curcumin nanoparticles ameliorated all the alterations induced by cisplatin in the heart of rats. This suggests that curcumin nanoparticles can be used as an important therapeutic adjuvant in chemotherapeutic and other toxicities mediated by oxidative stress and inflammation.

Cigarette smoke extract induces pyroptosis in human bronchial epithelial cells through the ROS/NLRP3/caspase-1 pathway

AIMS

Pyroptosis and inflammation are involved in the development of chronic obstructive pulmonary disease (COPD). However, the cigarette smoke-mediated mechanism of COPD remains unclear. In this study, we aimed to investigate the role of nucleotide-binding domain-like receptor protein-3 (NLRP3) inflammasome-mediated pyroptosis in the death of human bronchial epithelial (HBE) cells after cigarette smoke extract (CSE) exposure.

MAIN METHODS

The protein level of NLRP3 in lung tissue was measured after cigarette smoke exposure in vivo. In vitro, HBE cells were treated with CSE. Subsequently, the activity of caspase-1, lactate dehydrogenase (LDH) release, release of interleukin (IL)-1β and NLRP3 expression levels were measured. The involvement of reactive oxygen species (ROS) was also explored.

KEY FINDINGS

After exposure to CSE, increased release of LDH, the transcriptional and translational upregulation of NLRP3, the caspase-1 activity levels, and enhanced IL-1β and IL-18 release were observed in 16HBE cells. In addition, NLRP3 was required to activate the caspase-1. Our results suggested that pre-stimulated of 16HBE with a caspase-1 inhibitor, or using NLRP3 siRNA to silence NLRP3 expression, also caused the decrease of IL-1β release and pyroptosis.

SIGNIFICANCES

CSE induced inflammation and contributed to pyroptosis through the ROS/NLRP3/caspase-1 pathway in 16HBE cells. The NLRP3 inflammasome participates in CSE-induced HBE cell damage and pyroptosis, which could provide new insights into COPD.

Therapeutic potential of curcumin in diabetic retinopathy (Review)

Diabetic retinopathy (DR) is a type of retinal microangiopathy caused by diabetes mellitus. It has become the leading cause of blindness among working individuals worldwide. DR is becoming increasingly common among younger diabetic patients and there is a need for lifelong treatment. The pathogenic mechanisms of DR are influenced by a number of factors, such as hyperglycemia, hyperlipidemia, inflammatory response and oxidative stress, among others. Currently, the treatment methods for DR mainly include retinal photocoagulation, vitrectomy, or anti‑vascular endothelial growth factor (VEGF) therapy. However, these methods have some disadvantages and limitations. Therefore, it is a matter of great interest and urgency to discover drugs that can target the pathogenesis of DR. Since ancient times, traditional Chinese medicine practitioners have accumulated extensive experiences in the use of Chinese herbal medicine for the prevention and treatment of diseases. In the theory of traditional Chinese medicine, curcumin has the effects of promoting blood circulation and relieving pain. A number of studies have also demonstrated that curcumin has multiple biological activities, including exerting anti‑apoptotic, anti‑inflammatory, antioxidant and antitumor properties. In recent years, studies have also confirmed that curcumin can prevent a variety of diabetic complications, including diabetic nephropathy (DN). However, the preventive and curative effects of curcumin on DR and its mechanisms of action have not yet been fully elucidated. The present review aimed to explore the therapeutic potential of curcumin in diabetes mellitus and DR.

The Role of Chronic Inflammation in Various Diseases and Anti-inflammatory Therapies Containing Natural Products

Chronic inflammation represents a long-term reaction of the body's immune system to noxious stimuli. Such a sustained inflammatory response sometimes results in lasting damage to healthy tissues and organs. In fact, chronic inflammation is implicated in the development and progression of various diseases, including cardiovascular diseases, respiratory diseases, metabolic diseases, neurodegenerative diseases, and even cancers. Targeting nonresolving inflammation thus provides new opportunities for treating relevant diseases. In this review, we will go over several chronic inflammation-associated diseases first with emphasis on the role of inflammation in their pathogenesis. Then, we will summarize a number of natural products that exhibit therapeutic effects against those diseases by acting on different markers in the inflammatory response. We envision that natural products will remain a rich resource for the discovery of new drugs treating diseases associated with chronic inflammation.

Curcumin inhibits APOE4-induced injury by activating peroxisome proliferator-activated receptor-γ (PPARγ) in SH-SY5Y cells

Objective(s):

The human apolipoprotein E4 (APOE4) is associated with various brain injuries and neurodegenerative changes. Curcumin is an active ingredient isolated from the root of turmeric and is believed to have therapeutic effects on neurodegenerative diseases. The aim of this study was to investigate the effects of curcumin on APOE4-induced neurological damage and explore its molecular mechanisms.

Materials and Methods:

SH-SY5Y cells were pretreated with curcumin for 24 hr and transfected with human APOE4 gene using Lipofectamine 2000. Then, the effect of curcumin on the transfected cells was detected by ELISA, immunofluorescence staining and Western blot.

Results:

The production or expression of proinflammatory cytokines and proteins, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), nitric oxide (NO), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was significantly increased in SH-SY5Y cells transfected with APOE4, and curcumin inhibited APOE4-induced cellular inflammatory damage. Western blot analysis showed that, after transfection with APOE4, the expression of total nuclear factor kappa B (NF-κB) p65 and p-NF-κB p65 in the nucleus was increased, and curcumin inhibited the nuclear translocation of p65. The overexpression of APOE4 inhibited the expression of peroxisome proliferator-activated receptor-γ (PPARγ), whereas curcumin reversed and increased the expression of PPARγ protein. Down-regulating PPAR-γ with the inhibitor GW9662 and the shPPARγ gene confirmed that the NF-κB signaling pathway was inhibited by PPARγ.

Conclusion:

This study suggests that APOE4 overexpression can induce cellular inflammatory damage, and pretreatment of curcumin could exert an anti-inflammatory effect by upregulating the expression of PPARγ to inhibit the activation of NF-κB signaling pathway.

Mechanism of Action of Bu-Fei-Yi-Shen Formula in Treating Chronic Obstructive Pulmonary Disease Based on Network Pharmacology Analysis and Molecular Docking Validation

Objective

To explore the mechanism of action of Bu-Fei-Yi-Shen formula (BFYSF) in treating chronic obstructive pulmonary disease (COPD) based on network pharmacology analysis and molecular docking validation.

Methods

First of all, the pharmacologically active ingredients and corresponding targets in BFYSF were mined by the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, the analysis platform, and literature review. Subsequently, the COPD-related targets (including the pathogenic targets and known therapeutic targets) were identified through the TTD, CTD, DisGeNet, and GeneCards databases. Thereafter, Cytoscape was employed to construct the candidate component-target network of BFYSF in the treatment of COPD. Moreover, the cytoHubba plug-in was utilized to calculate the topological parameters of nodes in the network; then, the core components and core targets of BFYSF in the treatment of COPD were extracted according to the degree value (greater than or equal to the median degree values for all nodes in the network) to construct the core network. Further, the Autodock vina software was adopted for molecular docking study on the core active ingredients and core targets, so as to verify the above-mentioned network pharmacology analysis results. Finally, the Omicshare database was applied in enrichment analysis of the biological functions of core targets and the involved signaling pathways.

Results

In the core component-target network of BFYSF in treating COPD, there were 30 active ingredients and 37 core targets. Enrichment analysis suggested that these 37 core targets were mainly involved in the regulation of biological functions, such as response to biological and chemical stimuli, multiple cellular life processes, immunity, and metabolism. Besides, multiple pathways, including IL-17, Toll-like receptor (TLR), TNF, and HIF-1, played certain roles in the effect of BFYSF on treating COPD.

Conclusion

BFYSF can treat COPD through the multicomponent, multitarget, and multipathway synergistic network, which provides basic data for intensively exploring the mechanism of action of BFYSF in treating COPD.

The BRD4 inhibitor JQ1 protects against chronic obstructive pulmonary disease in mice by suppressing NF-κB activation

OBJECTIVE

To examine the effect of the BRD4 inhibitor JQ1 on mice with chronic obstructive pulmonary disease (COPD) via NF-κB.

METHODS

COPD models constructed by exposure to cigarette smoke and intratracheal instillation of lipopolysaccharides (LPS) in mice were treated with JQ1 (15, 25 or 50 mg/kg). HE staining was performed to observe histopathological changes in the lung tissues. Enzyme-linked immunosorbent assays (ELISAs) were used to measure the levels of IL-10, IFN-γ, IL-17, IL-1β, IL-6, TNF-α, MMP-2, MMP-9, MDA, SOD, T-AOC and HO-1, and gelatin zymography assays were used to examine MMP-2 and MMP-9 activity. A TransAMTM NF-κB p65 detection kit was used to test NF-κB p65/DNA binding activity. Western blotting was conducted to analyze NF-κB p65 in the nucleus and its acetylation.

RESULTS

JQ1 dose-dependently improved the histopathological changes in the lung tissues and decreased the mean linear intercept (MLI), destructive index and inflammatory score of the mice with COPD. The mice with COPD showed increased levels of MMP-2, MMP-9, IFN-γ, IL-17, IL-1β, IL-6 and TNF-α with decreased IL-10 level; these changes were reversed by JQ1 in a dose-dependent manner. In addition, JQ1 reduced the MDA level and increased the SOD, HO-1 and T-AOC levels in mice with COPD, with suppression of NF-κB p65 expression in the nucleus, NF-κB/p65 (Lys310) acetylation and NF-κB p65/DNA binding activity in the lung tissues.

CONCLUSION

The BRD4 inhibitor JQ1 can downregulate MMP-2 and MMP-9 expression, reduce inflammatory responses, and alleviate oxidative stress in mice with COPD, and this mechanism might be related to the inhibition of NF-κB.

Curcumin (a constituent of turmeric): New treatment option against COVID-19

In late December 2019, the outbreak of respiratory illness emerged in Wuhan, China, and spreads worldwide. World Health Organization (WHO) named this disease severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused by a new member of beta coronaviruses. Several medications are prescribed to patients, and some clinical trials are underway. Scientists are trying to find a specific drug against this virus. In this review, we summarize the pathogenesis, clinical features, and current treatments of coronavirus disease 2019 (COVID-19). Then, we describe the possible therapeutic effects of curcumin and its molecular mechanism against coronavirus-19. Curcumin, as an active constituent of Curcuma longa (turmeric), has been studied in several experimental and clinical trial studies. Curcumin has some useful clinical effects such as antiviral, antinociceptive, anti-inflammatory, antipyretic, and antifatigue effects that could be effective to manage the symptoms of the infected patient with COVID-19. It has several molecular mechanisms including antioxidant, antiapoptotic, and antifibrotic properties with inhibitory effects on Toll-like receptors, NF-κB, inflammatory cytokines and chemokines, and bradykinin. Scientific evidence suggests that curcumin could have a potential role to treat COVID-19. Thus, the use of curcumin in the clinical trial, as a new treatment option, should be considered.

Curcumin inhibits migration and invasion of non-small cell lung cancer cells through up-regulation of miR-206 and suppression of PI3K/AKT/mTOR signaling pathway

Curcumin has been proved to inhibit cell proliferation and induce cell apoptosis in non-small cell lung cancer (NSCLC). However, little is known about antimetastatic effects and molecular mechanisms of curcumin in NSCLC. In this study, we investigated the involvement of miR-206 in curcumin's anti-invasion and anti-migration in NSCLC. Cell proliferation was determined by MTT assay. Cell migration and invasion were analyzed by wound healing assay and transwell assay. MiRNA-206 expression was detected by real-time PCR. Western blot was used to detect the protein expression of PI3K/AKT/mTOR signaling pathway. Curcumin significantly inhibited migration and invasion in A549 cells, accompanied by significantly elevated miR-206 expression. Overexpression of miR-206 could inhibit migration and invasion of A549 cells, but it could also significantly decrease the phosphorylation levels of mTOR and AKT. The inhibition of miR-206 promoted cell migration, invasion and increased the phosphorylation level of mTOR and AKT. Furthermore, miR-206 mimics improved the inhibitory effects of curcumin on cell migration, invasion and the phosphorylation level of mTOR and AKT in A549 cells. On the contrary, MiR-206 inhibitors reversed the inhibitory effects of curcumin on cell migration, invasion and the phosphorylation level of mTOR and AKT. In conclusion, curcumin inhibited cell invasion and migration in NSCLC by elevating the expression of miR-206 which further suppressed the activation of the PI3K/AKT/mTOR pathway.

Anti-inflammatory Activity of Curcumin in Gel Carriers on Mice with Atrial Edema

Curcumin is a bioactive compound with proven antioxidant and anti-inflammatory activities, but has low water solubility and dermal absorption. The inflammatory process is considered as the biological response to damage induced by various stimuli. If this process fails to self-regulate, it becomes a potential risk of cancer. The objective of this work was to evaluate the anti-inflammatory activity of curcumin administered to mice with induced atrial edema using two topical vehicles: organogels and O/W-type nanogels at pH 7, Organogels and O/W-type nanogels at pH 7 were prepared, characterized and the anti-inflammatory activity was assessed. A histopathological analysis of mouse ears was performed and two gel formulations were selected. Thermograms of organogels indicated that increasing the gelling agent improved the stability of the system. Deformation sweeps confirmed a viscoelastic behavior characteristic of gels in both systems. During the anti-inflammatory activity evaluations, the nanogels demonstrated greater activity (61.8 %) than organogels; Diclofenac^® (2-(2,6-dichloranilino) phenylacetic acid), used as a control medication achieved the highest inhibition (85.4%); however, the drug produced the death of 2 (40%) of the study subjects caused by secondary adverse events. Histopathological analysis confirmed the data.

3,4,5-Trihydroxycinnamic acid exerts a protective effect on pulmonary inflammation in an experimental animal model of COPD

3,4,5-Trihydroxycinnamic acid (THCA), a derivative of hydroxycinnamic acid, has been reported to exert anti-inflammatory and antioxidant activities. However, its anti-inflammatory effects in chronic obstructive pulmonary disease (COPD) have not yet been elucidated. Therefore, we explored the protective effects of THCA on pulmonary inflammation in an experimental COPD model elicited by cigarette smoke (CS) and lipopolysaccharide (LPS). Oral administration of THCA significantly inhibited the activity of elastase, the release of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCP-1), myeloperoxidase (MPO) and the numbers of neutrophils and macrophages in the bronchoalveolar lavage fluid (BALF) of experimental COPD mice. THCA also exerted inhibitory effects on the recruitment of inflammatory cells, the levels of PAS positive cells and cAMP-response-element-binding protein (CREB) activation, and the expression of phosphodiesterase 4 (PDE4) in the lungs of experimental COPD mice. In addition, THCA exerted a regulatory effect on the activation of p38, ERK and nuclear factor-κB (NF-κB) in the lungs of experimental COPD mice. THCA also significantly upregulated the expression of NAD(P)H dehydrogenase (quinone 1) 1 (NQO1) and the activation of nuclear factor erythroid-derived 2-related factor 2 (Nrf2) in the lungs of mice. Furthermore, THC restored the reduction of NAD-dependent protein deacetylase sirtuin-1 (SIRT1) in the lungs of experimental COPD mice. In phorbol myristate acetate (PMA)-stimulated A549 or H292 airway epithelial cells, pretreatment of THCA dose-dependently inhibited the generation of IL-6. THCA also led to increased NQO1 expression in H292 cells. Collectively, these protective effects of antioxidant THCA were notably excellent and are thought to be associated with the downregulation of MAPK (partial)/NF-κB signaling and upregulation of NQO1 and SIRT1 expression.

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.

Curcumin-loaded poly-ε-caprolactone nanoparticles show antioxidant and cytoprotective effects in the presence of reactive oxygen species

Interest in novel delivery systems that improve the cytoprotective and antioxidant effects of natural drugs has been explored recently due to the increase in the incidence of chronic diseases in which oxidation mechanisms are involved. Curcumin is a phenolic compound recently shown to be clinically significant due to its anti-inflammatory, anticancer, and antioxidant properties. However, this molecule possesses a low bioavailability and a high degradation rate in the presence of light. Therefore, we prepared nanoparticles of poly-ε-caprolactone and Pluronic® F-68 as a stabilizer and loaded these with curcumin (Cur–PCL nanoparticles) for antioxidant and cytoprotective applications. The nanoparticles did not induce cell death, but they did reduce cell proliferation without affecting cell migration and cell adhesion. Interestingly, Cur–PCL and poly-ε-caprolactone nanoparticles reduced the oxidative stress induced by hydrogen peroxide and presented a cytoprotective effect. Remarkably, poly-ε-caprolactone nanoparticles showed a decrement of 30% in reactive oxygen species presence compared to the positive control. The decrease of reactive oxygen species derived from the administration of poly-ε-caprolactone nanoparticles could be attributed to the presence of Pluronic® F-68. Taken together, these data indicated that these nanoparticles might have a clinical application in disorders related to reactive oxygen species formation.

Nanocurcumin: A Promising Candidate for Therapeutic Applications

Curcuma longa is an important medicinal plant and a spice in Asia. Curcumin (diferuloylmethane) is a hydrophobic bioactive ingredient found in a rhizome of the C. longa. It has drawn immense attention in recent years for its variety of biological and pharmacological action. However, its low water solubility, poor bioavailability, and rapid metabolism represent major drawbacks for its successful therapeutic applications. Hence, researchers have attempted to enhance the biological and pharmacological activity of curcumin and overcome its drawbacks by efficient delivery systems, particularly nanoencapsulation. Research efforts so far and data from the available literature have shown a satisfactory potential of nanorange formulations of curcumin (Nanocurcumin), it increases all the biological and pharmacological benefits of curcumin, which was not significantly possible earlier. For the synthesis of nanocurcumin, an array of techniques has been developed and each technique has its own advantages and individual characteristics. The two most popular and effective techniques are ionic gelation and antisolvent precipitation. So far, many curcumin nanoformulations have been developed to enhance curcumin delivery, thereby overcoming the low therapeutic effects. However, most of the nanoformulation of curcumin remained at the concept level evidence, thus, several questions and challenges still exist to recommend the nanocurcumin as a promising candidate for therapeutic applications. In this review, we discuss the different curcumin nanoformulation and nanocurcumin implications for different therapeutic applications as well as the status of ongoing clinical trials and patents. We also discuss the research gap and future research directions needed to propose curcumin as a promising therapeutic candidate.