Curcumin inhibits lipopolysaccharide (LPS)-induced endotoxemia and airway inflammation through modulation of sequential release of inflammatory mediators (TNF-α and TGF-β1) in murine model

RESEARCH PROGRESS OF CURCUMIN IN THE TREATMENT OF SEPSIS

ABSTRACT

Sepsis is a life-threatening organ dysfunction caused by an unregulated host response to infection. It is an important clinical problem in acute and critical care. In recent years, with the increasing research on the epidemiology, and pathogenesis, diagnostic and therapeutic strategies of sepsis, great progress has been made in clinical practice, but there is still a lack of specific and effective treatment plans. Curcuma longa , a leafy plant of the ginger family, which is a common and safe compound, has multiple pharmacological actions, including, but not limited to, scavenging of oxygen free radicals, attenuation of inflammatory response, and antifibrotic effects. Great progress has been made in the study of sepsis-associated rodent models and in vitro cellular models. However, the evidence of curcumin in the clinical management practice of sepsis is still insufficient; hence, it is very important to systematically summarize the study of curcumin and sepsis pathogenesis.

Curcumin/TGF-β1 siRNA loaded solid lipid nanoparticles alleviate cerebral injury after intracerebral hemorrhage by transnasal brain targeting

Intracerebral hemorrhage (ICH) is a prevalent cerebrovascular disorder. The inflammation induced by cerebral hemorrhage plays a crucial role in the secondary injury of ICH and often accompanied by a poor prognosis, leading to disease exacerbation. However, blood-brain barrier (BBB) limiting the penetration of therapeutic drugs to the brain. In this paper, our primary objective is to develop an innovative, non-invasive, safe, and targeted formulation. This novel approach aims to synergistically harness the combined therapeutic effects of drugs to intervene in inflammation via a non-injectable route, thereby significantly mitigating the secondary damage precipitated by inflammation following ICH. Thus, a novel "anti-inflammatory" cationic solid lipid nanoparticles (SLN) with targeting ability were constructed, which can enhance the stability of curcumin(CUR) and siRNA. We successfully developed SLN loaded with TGF-β1 siRNA and CUR (siRNA/CUR@SLN) that adhere to the requirements of drug delivery system by transnasal brain targeting. Through the characterization of nanoparticle properties, cytotoxicity assessment, in vitro pharmacological evaluation, and brain-targeting evaluation after nasal administration, siRNA/CUR@SLN exhibited a nearly spherical structure with a particle size of 125.0±1.93 nm, low cytotoxicity, high drug loading capacity, good sustained release function and good stability. In vitro anti-inflammatory results showcasing its remarkable anti-inflammatory activity. Moreover, in vivo pharmacological studies revealed that siRNA/CUR@SLN can be successfully delivered to brain tissue. Furthermore, it also elicited an effective anti-inflammatory response, alleviating brain inflammation. These results indicated that favorable brain-targeting ability and anti-inflammatory effects of siRNA/CUR@SLN in ICH model mice. In conclusion, our designed siRNA/CUR@SLN showed good brain targeting and anti-inflammatory effect ability after nasal administration, which lays the foundation for the treatment of inflammation caused by ICH and offers a novel approach for brain-targeted drug delivery and brings new hope.

Selenium prevented renal tissue damage in lipopolysaccharide-treated rats

OBJECTIVES

Kidney diseases are one of the common diseases, which are one of the main causes of death in society and impose costs on the health system of the society. A growing body of evidence has well documented that inflammatory responses and oxidative damage play a significant role in the progress of various kidney diseases.

METHODS

This study examined whether selenium (Sel) could prevent the detrimental influences of lipopolysaccharide (LPS) in rats. Four groups of Wistar rats were considered: control, LPS (1 mg/kg, i.p., for 14 days), LPS-Sel 1 (0.1 mg/kg, i.p., for 14 days), and LPS-Sel 2 (0.2 mg/kg, i.p., for 14 days).

RESULTS

Sel treatment markedly attenuated oxidative stress damage in the kidney tissue in LPS-induced renal toxicity. Generally, the administration of Sel resulted in improved antioxidant indicators such as catalase (CAT) and superoxide dismutase (SOD) activities, or total thiol content, and decreased malondialdehyde (MDA) in the kidney tissue. It also decreased interleukin-6 in kidney homogenates. Furthermore, Se treatment significantly inhibited the elevation of serum biochemical markers of kidney function including serum, BUN, and creatinine.

CONCLUSIONS

Based on the findings of the current study, it seems that the administration of Sel to LPS-treated rats improves renal function by reducing oxidative damage and inflammation in kidney tissue. However, more research is needed to reveal the accurate mechanisms for the effect of Sel on renal outcomes of LPS in human subjects.

Astaxanthin suppresses LPS-induced myocardial apoptosis by regulating PTP1B/JNK pathway in vitro

PURPOSE

Myocardial injury induced by sepsis can increase the patient's mortality, which is an important complication of sepsis. Myocardial apoptosis plays a key role in septic myocardial injury. Here we explored the potential mechanism of astaxanthin (ATX) inhibiting myocardial apoptosis induced by lipopolysaccharide (LPS) in vitro.

METHODS

The H9C2 cell experiment was conducted in three parts. In the first part, we set up three groups: control group, LPS group (10 µg/ml), a model of septic myocardial injury, and LPS + ATX (5, 10, 30 µM); In the second part, we set up four groups: control group, LPS group, LPS + PTP1B-IN-1, a protein tyrosine phosphatase 1B (PTP1B) inhibitor, and LPS + PTP1B-IN-1 + ATX; In the third part, we set up four groups: control group, LPS group, LPS + Anisomycin, a c-Jun N-terminal kinase (JNK) activator, and LPS + Anisomycin + ATX. We assessed H9C2 cell viability using the Cell Counting Kit-8 (CCK-8) assay. We observed cell apoptosis using flow cytometry analysis. We tested the mitochondrial membrane potential (ΔΨm) using JC-1 staining. To identify the molecular targets of ATX, Astaxanthin targets were predicted through the SwissTargetPrediction database. We verified the binding affinity of ATX and its targets using microscale thermophoresis (MST). We investigated the p-JNK expression using immunofluorescence staining. Finally, Western blot was used to evaluate PTP1B, JNK, p-JNK and the mitochondrial apoptosis-associated protein expression.

RESULTS

LPS inhibited H9C2 cell viability in a time-dependent manner and ATX treatment enhances H9C2 cell viability in a concentration dependent manner after LPS administration. ATX inhibited the LPS-induced apoptosis and loss of mitochondrial membrane potential in H9C2 cells. As predicted by the SwissTargetPrediction database, PTP1B was a potential target of ATX, and the interaction between ATX and PTP1B was further verified by MST. ATX attenuated the LPS-induced protein expression of PTP1B and p-JNK, regardless of PTP1B inhibition. Both immunofluorescence staining and Western blotting showed that ATX suppressed the LPS-induced p-JNK expression in H9C2 cells, regardless of Anisomycin administration. In addition, by adding Anisomycin to overexpress JNK, ATX inhibited the LPS-induced apoptosis, loss of mitochondrial membrane potential and upregulation of mitochondrial apoptosis-associated proteins in H9C2 cells via JNK signaling.

CONCLUSION

ATX inhibited LPS-induced mitochondrial apoptosis of H9C2 cells by PTP1B/JNK pathway and PTP1B was the target of ATX.

AjTGFβ alleviates V. splendidus-induced inflammation through SMADs pathway in Apostichopus japonicus

The inhibition of inflammatory response is an essential process to control the development of inflammation and is an important step to protect the organism from excessive inflammatory damage. As a pleiotropic cytokine, transforming growth factor beta (TGF-β) plays a regulatory role in inhibiting inflammation in vertebrates. To investigate the role of TGF-β in the regulation of inflammation in invertebrates, we cloned and characterized the TGF-β gene from Apostichopus japonicus via rapid amplification of cDNA ends, and the sample was designated as AjTGF-β. For Vibrio splendidus-challenged sea cucumbers, the expression of AjTGF-β mRNAs in coelomocytes decreased at 96 h (0.27-fold), which was contrary to the trend of inflammation. AjTGF-β was expressed in all tissues with the highest expression in the body wall. When AjTGF-β was knocked down by using small interfering RNA (siRNA-KD) to 0.45-fold, AjSMAD 2/3 and AjSMAD6 were downregulated to 0.32- and 0.05-fold compared with the control group, respectively. Furthermore, when the damaged sea cucumber was challenged by V. splendidus co-incubated with rAjTGF-β, the damage area had no extensive inflammation, and damaged repair appeared at 72 h compared with the Vs + BSA group, in which the expression of AjSMAD 2/3 was upregulated by 1.35-fold. Under this condition, AjSMAD 2/3 silencing alleviated rAjTGF-β-induced damage recovery. Moreover, rAjTGF-β slightly induced the collagen I expression from 6.13 ng/mL to 7.84 ng/mL, and collagen III was upregulated from 6.23 ng/mL to 6.89 ng/mL compared with the Vs + BSA group. This finding indicates that AjTGF-β negatively regulated the inflammatory progress and accelerated the repair of damage by AjSMADs to regulate the collagens expression.

Impacts of Curcumin Treatment on Experimental Sepsis: A Systematic Review

Background and Aims

Sepsis is defined as a life-threatening organ dysfunction due to a dysregulated host immune response to an infection. Curcumin is a yellow polyphenol derived from the rhizome of Curcuma longa with anti-inflammatory and antioxidant properties scientifically proven, a condition that allowed its use as a tool in the treatment of sepsis. Thus, the purpose of this article was to systematically review the evidence on the impact of curcumin's anti-inflammatory effect on experimental sepsis.

Methods

For this, the PubMed, MEDLINE, EMBASE, Scopus, Web of Science, and LILACS databases were used, and the research was not limited to a specific publication period. Only original articles in English using in vivo experimental models (rats or mice) of sepsis induction performed by administration of lipopolysaccharide (LPS) or cecal ligation and perforation surgery (CLP) were included in the study. Studies using curcumin in dry extract or with a high degree of purity were included. At initial screening, 546 articles were selected, and of these, 223 were eligible for primary evaluation. Finally, 12 articles with full text met all inclusion criteria. Our results showed that curcumin may inhibit sepsis-induced complications such as brain, heart, liver, lungs, and kidney damage. Curcumin can inhibit inflammatory factors, prevent oxidative stress, and regulate immune responses in sepsis. Additionally, curcumin increased significantly the survival rates after experimental sepsis in several studies. The modulation of the immune response and mortality by curcumin reinforces its protective effect on sepsis and indicates a potential therapeutic tool for the treatment of sepsis.

Micellar Curcumin: Pharmacokinetics and Effects on Inflammation Markers and PCSK-9 Concentrations in Healthy Subjects in a Double-Blind, Randomized, Active-Controlled, Crossover Trial

SCOPE

Preclinical models have demonstrated the anti-inflammatory and lipid-lowering effects of curcumin. Innovative formulations have been developed to overcome the poor bioavailability of native curcumin. The study hypothesizes that the bioavailability of micellar curcumin is superior to native curcumin and investigates the potential anti-inflammatory and proprotein convertase subtilisin/kexin type 9 (PCSK9) concentration lowering effects.

METHODS AND RESULTS

In this double-blind, randomized, crossover trial, 15 healthy volunteers receive micellar or native curcumin (105 mg day^-1 ) for 7 days with a ≥7 days washout period. Curcumin and metabolite concentrations are quantified by high-performance liquid chromatography with fluorescence detection (HPLC-FD), and pharmacokinetics are calculated. To analyze anti-inflammatory effects, blood samples (baseline, 2 h, 7 days) are stimulated with 50 ng mL^-1 lipopolysaccharides (LPS). Interleukin (IL)-6, tumor-necrosis factor (TNF-α), and PCSK9 concentrations are quantified. Micellar curcumin demonstrates improved bioavailability (≈39-fold higher maximum concentrations, ≈14-fold higher area-under-the-time-concentration curve, p < 0.001) but does not reduce pro-inflammatory cytokines in the chosen model. Subjects receiving micellar curcumin have significantly lower PCSK9 concentrations (≈10% reduction) after 7 days compared to baseline (p = 0.038).

CONCLUSION

Micellar curcumin demonstrates an improved oral bioavailability but does not show anti-inflammatory effects in this model. Potential effects on PCSK9 concentrations warrant further investigation.

Curcumin Elevates microRNA-183-5p via Cathepsin B-Mediated Phosphatidylinositol 3-Kinase/AKT Pathway to Strengthen Lipopolysaccharide-Stimulated Immune Function of Sepsis Mice

Curcumin (Cur), a natural polyphenol compound, has been testified to modulate innate immune responses and also showed anti-inflammatory properties. Nevertheless, the mechanism was still poorly unknown, especially regarding Cur-modulated microRNAs (miRNAs) under the inflammatory response. CD39⁺ regulatory T cells (Tregs) were provided with distinct immunosuppressive action and exerted a critical role in the modulation of immune balance in sepsis. Nevertheless, the impact of Cur on the immune function of sepsis mice has not been reported. In this study, the influence of Cur on the inflammatory response and immune function of sepsis mice via augment of miR-183-5p and Cathepsin B (CTSB)-mediated phosphatidylinositol 3-kinase (PI3K)/AKT pathway was explored. Adoption of 20 mg/kg Cur was for gavage. In the meantime, injection of plasmid vectors of interference with miR-183-5p or CTSB was into the tail vein. Intraperitoneal injection of lipopolysaccharide (10 mg/kg) was to stimulate model of sepsis mice. Histopathological changes of sepsis mice were observed. The contents of tumor necrosis factor-α and Interleukin (IL)-1β and IL-6 in serum of mice were examined. Detection of alanine aminotransferase, aspartate aminotransferase (AST), urea nitrogen (BUN), and creatinine in serum of mice was performed. Test of the percentage of CD39⁺ Tregs in tail venous blood of mice was implemented. Examination of miR-183-5p, CTSB, and PI3K/AKT was performed. The targeting of miR-183-5p and CTSB was detected. Cur was available to ameliorate the histological damage, to reduce the content of inflammatory factors, AST, and BUN, and to decline the percentage of CD39⁺ Tregs in tail venous blood of sepsis mice. Elevated miR-183-5p or silenced CTSB was available to further enhance the protection of Cur. Cur was available to accelerate miR-183-5p, which negatively modulated CTSB and Cur-mediated PI3K/AKT pathway via the miR-183-5p/CTSB axis to restrain inflammation of sepsis mice and enhance its immune function.

NRIP1 aggravates lung injury caused by Pseudomonas aeruginosa in mice by increasing PIAS1 ubiquitination

Recently, evidence has shown that nuclear receptor interacting protein 1 (NRIP1) is involved in acute lung injury (ALI) progression, but the specific mechanism remains unclear. Pseudomonas aeruginosa (PA)-treated TC-1 cells were transfected with pcDNA-NRIP1 or si-NRIP1, and we found that overexpression of NRIP1 inhibited cell viability and promoted cell apoptosis and secretion of inflammatory factors, and transfection of si-NRIP1 reversed these effects. Furthermore, online bioinformatics analysis and co-immunoprecipitation assay results indicated that NRIP1 could bind to Ubiquitin Conjugating Enzyme E2I (UBE2I), and promoted UBE2I expression. Next, the PA-treated TC-1 cells were transfected with si-NRIP1 alone or together with pcDNA-UBE2I, and we observed that transfection with si-NRIP1 inhibited UBE2I expression, promoted cell viability, and reduced cell apoptosis and inflammatory factor secretion, which could be reversed by UBE2I overexpression. Moreover, UBE2I could bind to protein inhibitor of activated signal transducer and activators of transcription 1 (PIAS1). Overexpression of NRIP1 promoted UBE2I expression and inhibited PIAS1 expression, and NRIP1 promoted PIAS1 ubiquitination and degradation by UBE2I. The PA-treated TC-1 cells were transfected with si-UBE2I alone or together with si-PIAS1, and the results indicated that transfection of si-UBE2I had the same effect as transfection of si-NRIP1. Finally, our in vivo findings indicated that the expression of NRIP1 and UBE2I was decreased, and PIAS1 expression was increased, in the lung tissues of mice with NRIP1 knocked-down, and the inflammatory infiltration in the lung tissue was reduced. In conclusion, our study demonstrates that NRIP1 aggravates PA-induced lung injury in mice by promoting PIAS1 ubiquitination.

Intranasal curcumin and dexamethasone combination ameliorates inflammasome (NLRP3) activation in lipopolysachharide exposed asthma exacerbations

The inflammasome NOD-like receptor (NLR) family, the pyrin domain containing 3 (NLRP3) is closely associated with exacerbation of asthma as endotoxin (lipopolysaccharide, LPS) is one of its activators present in the environment. Present study is undertaken to investigate anti-inflammatory effects of a well known phytochemical, curcumin, which might regulate LPS exposed asthma exacerbations by modulating NLRP3 activation if given through intranasal route. Balb/c mice were sensitized with intraperitoneal injection of OVA (Ovalbumin; 100 μg of OVA with alum) from day 1 to 8 and exposed to LPS with 1% OVA aerosol from day 9 to 15. LPS (0.1 μg) was given an hour before sensitization and OVA-aerosol challenge. Significant decrease in inflammatory cell recruitment and restoration of structural changes in lungs, alterations in mRNA and protein expressions of TLR-4, NF-κB, NLRP3, Caspase-1, IL-1β, MMP-9, IL-5 and IL-17 in intranasal curcumin alone and corticosteroid combined pretreatment group.

Pulmonary delivery of curcumin-loaded glycyrrhizic acid nanoparticles for anti-inflammatory therapy

Curcumin was loaded into the glycyrrhizic acid nanoparticles and delivered into the lungs for the treatment of acute lung injury.

2,4,6-Trihydroxy-3-geranyl acetophenone suppresses vascular leakage and leukocyte infiltration in lipopolysaccharide-induced endotoxemic mice

CONTEXT

Lipopolysaccharide (LPS) exacerbates systemic inflammatory responses and causes excessive fluid leakage. 2,4,6-Trihydroxy-3-geranyl acetophenone (tHGA) has been revealed to protect against LPS-induced vascular inflammation and endothelial hyperpermeability in vitro.

OBJECTIVE

This study assesses the in vivo protective effects of tHGA against LPS-induced systemic inflammation and vascular permeability in endotoxemic mice.

MATERIALS AND METHODS

BALB/c mice were intraperitoneally pre-treated with tHGA for 1 h, followed by 6 h of LPS induction. Evans blue permeability assay and leukocyte transmigration assay were performed in mice (n = 6) pre-treated with 2, 20 and 100 mg/kg tHGA. The effects of tHGA (20, 40 and 80 mg/kg) on LPS-induced serum TNF-α secretion, lung dysfunction and lethality were assessed using ELISA (n = 6), histopathological analysis (n = 6) and survivability assay (n = 10), respectively. Saline and dexamethasone were used as the negative control and drug control, respectively.

RESULTS

tHGA significantly inhibited vascular permeability at 2, 20 and 100 mg/kg with percentage of inhibition of 48%, 85% and 86%, respectively, in comparison to the LPS control group (IC₅₀=3.964 mg/kg). Leukocyte infiltration was suppressed at 20 and 100 mg/kg doses with percentage of inhibition of 73% and 81%, respectively (IC₅₀=17.56 mg/kg). However, all tHGA doses (20, 40 and 80 mg/kg) failed to prevent endotoxemic mice from lethality because tHGA could not suppress TNF-α overproduction and organ dysfunction.

DISCUSSION AND CONCLUSIONS

tHGA may be developed as a potential therapeutic agent for diseases related to uncontrolled vascular leakage by combining with other anti-inflammatory agents.

Curcumin attenuates prostatic hyperplasia caused by inflammation via up-regulation of bone morphogenetic protein and activin membrane-bound inhibitor

CONTEXT

Inflammation and epithelial-mesenchymal transition (EMT) play important roles in the occurrence and development of benign prostatic hyperplasia (BPH); curcumin exerts anti-proliferative, anti-inflammatory, and anti-EMT effects.

OBJECTIVE

To explore the anti-inflammatory and anti-EMT mechanisms of curcumin in BPH.

MATERIALS AND METHODS

Ten-week-old male C57BL/6 mice were administered lipopolysaccharide (LPS, 100 µg/kg) in the prostate lobules to establish an inflammatory BPH model (LPS group), and curcumin (120 mg/kg) was administered into the abdominal cavity for 2 weeks (three times a week, curcumin-treated group). A group of healthy mice served as the control group. The expression of Toll-like receptor 4 (TLR4), bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI), EMT markers, inflammatory cytokines, and transforming growth factor β1 (TGF-β1) was detected by PCR and western blotting. TGF-β1 (0.1 ng/mL) and LPS (100 ng/mL) were used to induce EMT in benign prostatic hyperplasia epithelial cells (BPH-1).

RESULTS

In vivo, curcumin reduced the size of the prostate, suppressed the expression of vimentin and TLR4, and increased the expression of E-cadherin and BAMBI in the LPS-induced BPH mouse model. Moreover, curcumin decreased the levels of IL-6 and TNF-α by 44.52 and 46.17%, respectively. In vitro, curcumin attenuated cell proliferation, suppressed the expression of vimentin and TLR4, and increased the expression of E-cadherin and BAMBI in BPH-1 cells. Furthermore, BAMBI knockdown reversed the expression of vimentin and E-cadherin induced by curcumin.

DISCUSSION AND CONCLUSION

This study demonstrated that curcumin alleviated hyperplasia, EMT, and inflammation in vivo. Furthermore, curcumin suppressed EMT by targeting BAMBI via the TLR4/BAMBI/TGF-β1 signalling pathway in vitro, demonstrating its potential utility in BPH treatment.

Immunomodulatory Effects of Herbal Compounds Quercetin and Curcumin on Cellular and Molecular Functions of Bovine-Milk-Isolated Neutrophils toward Streptococcus agalactiae Infection

Herbal phytochemicals featuring active ingredients including quercetin and curcumin have shown potential in treating human and animal diseases. The current study investigated their potential function in vitro for host immunomodulation associated with Streptococcus agalactiae subclinical bovine mastitis via milk-isolated neutrophils. Our results showed a positive influence on cellular migration, reactive oxygen species (ROS) generation, phagocytosis, and bacterial killing as well as neutrophil extracellular traps (NETs) release. This study also highlighted several important molecular aspects of quercetin and curcumin in milk-isolated neutrophils. Gene expression analyses by RT-PCR revealed significant changes in the expression of proinflammatory cytokines (IL1B, IL6, and TNF), ROS (CYBA), phagocytosis (LAMP1), and migration (RAC). The expression levels of apoptotic genes or proteins in either pro-apoptosis (CASP3 and FAS) or anti-apoptosis (BCL2, BCL2L1, and CFLAR) were significantly manipulated by the effects of either quercetin or curcumin. A principal component analysis (PCA) identified the superior benefit of quercetin supplementation for increasing both cellular and molecular functions in combating bacterial mastitis. Altogether, this study showed the existing and potential benefits of these test compounds; however, they should be explored further via in vivo studies.

Curcumin Reduces Adipose Tissue Inflammation and Alters Gut Microbiota in Diet-Induced Obese Male Mice

SCOPE

Obesity prevalence continues to increase and contribute to metabolic diseases, potentially by driving systemic inflammation. Curcumin is an anti-inflammatory spice with claimed health benefits. However, mechanisms by which curcumin may reduce obesity-associated inflammation are poorly understood; thus, it is hypothesized that benefits of curcumin consumption may occur through reduced white adipose tissue (WAT) inflammation and/or beneficial changes in gut bacteria.

METHODS AND RESULTS

Male B6 mice are fed high-fat diets (HFD, 45% kcal fat) or HFD supplemented with 0.4% (w/w) curcumin (HFC) for 14 weeks. Curcumin supplementation significantly reduces adiposity and total macrophage infiltration in WAT, compared to HFD group, consistent with reduced mRNA levels of M1 (Cd80, Cd38, Cd11c) and M2 (Arginase-1) macrophage markers. Moreover, curcumin supplementation reduces expression of other key pro-inflammatory genes, such as NF-κB p65 subunit (p65), Stat1, Tlr4, and Il6, in WAT (p < 0.05). Using microbial 16S RNA sequencing, it is demonstrated that the relative abundance of the Lactococcus, Parasutterella, and Turicibacter genera are increased in the HFC group versus HFD.

CONCLUSIONS

Curcumin exerts protective metabolic effects in dietary obesity, in part through downregulation of adipose tissue inflammation, which may be mediated by alterations in composition of gut microbiota, and metabolism of curcumin into curcumin-O-glucuronide.

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.

Lipopolysaccharide-induced inflammation in human peritoneal mesothelial cells is controlled by ERK1/2-CDK5-PPARγ axis

Background

Peritonitis is a common complication in which the peritoneum becomes inflamed. Peroxisome proliferator-activated receptor (PPAR)γ agonists and extracellular signal-regulated kinases 1/2 (ERK1/2) inactivation have been found to restore damage caused by lipopolysaccharide-induced (LPS) inflammation. This study aimed to investigate the association between PPARγ and ERK1/2 in LPS-induced inflammation in peritonitis.

Methods

Human peritoneal mesothelial cells were maintained in Dulbecco’s Modified Eagle Medium and treated with LPS under a series of different concentrations and treatment times. Cellular interleukins-1βeta (IL-1β), cellular interleukins-6 (IL-6), cellular interleukins-12 (IL-12) were measured by enzyme-linked immunosorbent assay (ELISA) assay. Expression or activation of cyclin-dependent kinase (CDK)5, ERK1/2, and PPARγ was detected using quantitative real-time PCR and/or western blot.

Results

LPS induced dose- and time-dependent increments in the cellular IL-1β, IL-6, and IL-12 contents, cyclin-dependent kinase 5 (CDK5) expression, and PPARγ^Ser273 phosphorylation. Treatment with 1 µg/mL LPS for 12 hours was the optimal experimental design for inflammation stimulation. The concentration of LPS over 1 µg/mL or treatment more than 12 hours reduced the inflammatory status. LPS stimulation also activated ERK1/2 and increased its interaction with CDK5. Further, ERK1/2 inhibition by AZD0364 prevented IL-1β, IL-6, IL-12, and CDK5 expression, as well as activation of ERK1/2 and phosphorylation of PPARγ, induced by LPS. Knockdown of CDK5 using its siRNA caused similar changes as AZD0364, minus ERK1/2 inactivation.

Conclusions

Our results suggested that LPS-induced inflammation in human peritoneal mesothelial cells can be partly suppressed by inhibiting the ERK1/2/CDK5/PPARγ axis.

Preparation of Curdlan sulphate - Chitosan nanoparticles as a drug carrier to target Mycobacterium smegmatis infected macrophages

In this study, curdlan sulphate - chitosan nanoparticles were prepared through polyelectrolyte complexing at a mass ratio of 2:1 respectively. The curdlan was produced by fermentation with Agrobacterium sp. ATCC 31750, which was then sulphated to form the polyanionic polymer. A first-line tuberculosis drug, Rifampicin and a phytochemical, DdPinitol, were encapsulated into Curdlan Sulphate (CS) - Chitosan Nanoparticles (C) (CSC NPs) of size 205.41 ± 7.24 nm. The drug release kinetics followed a Weibull model with initial burst release (48 % Rifampicin and 27 % d-Pinitol within 6 h), followed by a sustained release. The prepared CSC: d-PIN + RIF NPs was cytocompatible and entered the M.smegmatis infected macrophages through multiple endocytic pathways including clathrin, caveolae and macropinocytosis. They showed superior bactericidal activity (2.4-2.7 fold) within 4 h when compared to free drug Rifampicin (1.6 fold). The drug encapsulated CSC: RIF suppressed the pro-inflammatory gene (TNF-α by 3.66 ± 0.19 fold) and CSC: d-PIN + RIF increased expression of the anti-inflammatory gene (IL-10 by 13.09 ± 0.47 fold). Expression of TGF- β1 gene also increased when treated with CSC: d-PIN + RIF (13.00 ± 0.19 fold) which provided the immunomodulatory activity of the encapsulated CSC NPs. Thus, curdlan sulphate - chitosan polyelectrolyte complex can be a potential nanocarrier matrix for intracellular delivery of multiple drugs.

Reactive oxygen species induce Cys106-mediated anti-parallel HMGB1 dimerization that protects against DNA damage

Oxidative stress can induce covalent disulfide bond formation between protein-protein thiol groups and generate hydroxyl free radicals that damage DNA. HMGB1 is a DNA chaperone and damage-associated molecular pattern molecule. As a redox-sensitive protein, HMGB1 contains three cysteine residues: Cys23, Cys45, and Cys106. In this study, we focused on the relationship between HMGB1 dimerization and DNA stabilization under oxidative stress conditions. HMGB1 dimerization was positively modulated by CuCl₂ and H₂O₂. Mutation of the Cys106 residue blocked dimer formation. Treatment of HEK293T cells with CuCl₂ and H₂O₂ enhanced the oxidative self-dimerization of HMGB1, whereas this dimerization was inhibited in mutant HMGB1^C106A cells. Furthermore, we performed a bimolecular fluorescence complementation assay to visualize Cys106 oxidation-induced HMGB1 dimerization in live cells exposed to oxidative stress and were able to reproduce the dimerization effect of HMGB1 in fluorescence resonance energy transfer analysis. Interestingly, dimerized HMGB1 bound to DNA with higher affinity than monomeric HMGB1. Dimerized HMGB1 protected DNA from damage due to hydroxyl free radicals and prevented cell death. In conclusion, dimerized HMGB1 may play a regulatory role in DNA stabilization under oxidative stress.

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Accumulation of excessive ROS induces DNA damage, causing cell death.

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HMGB1 dimerizes in the presence of excessive ROS and binds DNA with high affinity.

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Binding of dimerized HMGB1 (Di-HMGB1) protects DNA from ROS action.

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We prepared an in vitro HMGB1 dimerization due to excessive ROS.

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Di-HMGB1 protected against DNA damage induced by radiation exposure.

The role of phytochemicals in sepsis: A mechanistic and therapeutic perspective

Sepsis and septic shock are still a leading cause of mortality and morbidity in intensive care units worldwide. Sepsis is an uncontrolled and excessive response of the innate immune system toward the invading infectious microbes, characterized by the hyper-production of pro-inflammatory mediators such as interleukin (IL)-1β, IL-6, tumor-necrosis factor (TNF)-α, and high-mobility group box 1 (HMGB1). In severe sepsis, the overwhelming production of pro-inflammatory cytokines and reactive oxygen species may compromise organ function and lead to the induction of abnormal apoptosis in different organs, resulting in multiple organ dysfunction syndrome and death. Hence, compounds that are able to attenuate inflammatory responses may have therapeutic potential for sepsis treatment. Understanding the pathophysiology and underlying molecular mechanisms of sepsis may provide useful insights in the discovery and development of new effective therapeutics. Therefore, numerous studies have invested much effort into elucidating the mechanisms involved with the onset and development of sepsis. The present review mainly focuses on the molecules and signaling pathways involved in the pathogenicity of sepsis. Additionally, several well-known natural bioactive herbal compounds and phytochemicals, which have shown protective and therapeutic effects with regard to sepsis, as well as their mechanisms of action, are presented. This review suggests that these phytochemicals are able to attenuate the overwhelming inflammatory responses developed during sepsis by modulating different signaling pathways. Moreover, the anti-inflammatory and cytoprotective activities of phytochemicals make them potent compounds to be included as complementary therapeutic agents in the diets of patients suffering from sepsis in an effort to alleviate sepsis and its life-threatening complications, such as multi-organ failure.

Toward Regulatory Effects of Curcumin on Transforming Growth Factor-Beta Across Different Diseases: A Review

Immune response, proliferation, migration and angiogenesis are juts a few of cellular events that are regulated by transforming growth factor-β (TGF-β) in cells. A number of studies have documented that TGF-β undergoes abnormal expression in different diseases, e.g., diabetes, cancer, fibrosis, asthma, arthritis, among others. This has led to great fascination into this signaling pathway and developing agents with modulatory impact on TGF-β. Curcumin, a natural-based compound, is obtained from rhizome and roots of turmeric plant. It has a number of pharmacological activities including antioxidant, anti-inflammatory, anti-tumor, anti-diabetes and so on. Noteworthy, it has been demonstrated that curcumin affects different molecular signaling pathways such as Wnt/β-catenin, Nrf2, AMPK, mitogen-activated protein kinase and so on. In the present review, we evaluate the potential of curcumin in regulation of TGF-β signaling pathway to corelate it with therapeutic impacts of curcumin. By modulation of TGF-β (both upregulation and down-regulation), curcumin ameliorates fibrosis, neurological disorders, liver disease, diabetes and asthma. Besides, curcumin targets TGF-β signaling pathway which is capable of suppressing proliferation of tumor cells and invading cancer cells.

Therapeutic Potential of Exosomes in Pulmonary Fibrosis

Pulmonary fibrosis is closely associated with the recruitment of fibroblasts from capillary vessels with damaged endothelial cells, the epithelial mesenchymal transition (EMT) of type II alveolar epithelial cells, and the transformation of fibroblasts to myofibroblasts. Recent studies suggest that EMT is a key factor in the pathogenesis of pulmonary fibrosis, as the disruption of EMT-related effector molecules can inhibit the occurrence and development of PF. With the numerous advancements made in molecular biology in recent years, researchers have discovered that exosomes and their cargos, such as miRNAs, lncRNAs, and proteins, can promote or inhibit the EMT, modulate the transformation of fibroblasts into myofibroblasts, contribute to the proliferation of fibroblasts and promote immunoregulatory and mitochondrial damage during pulmonary fibrosis. Exosomes are key factors regulating the differentiation of bone marrow mesenchymal stem cells (BMSCs) into myofibroblasts. Interestingly, exosomes derived from BMSCs under pathological and physiological conditions may promote or inhibit the EMT of type II alveolar epithelial cells and the transformation of fibroblasts into myofibroblasts to regulate pulmonary fibrosis. Thus, exosomes may become a new direction in the study of drugs for the treatment of pulmonary fibrosis.

A Review of Malaysian Herbal Plants and Their Active Constituents with Potential Therapeutic Applications in Sepsis

Sepsis refers to organ failure due to uncontrolled body immune responses towards infection. The systemic inflammatory response triggered by pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide (LPS) from Gram-negative bacteria, is accompanied by the release of various proinflammatory mediators that can lead to organ damage. The progression to septic shock is even more life-threatening due to hypotension. Thus, sepsis is a leading cause of death and morbidity globally. However, current therapies are mainly symptomatic treatment and rely on the use of antibiotics. The lack of a specific treatment demands exploration of new drugs. Malaysian herbal plants have a long history of usage for medicinal purposes. A total of 64 Malaysian plants commonly used in the herbal industry have been published in Malaysian Herbal Monograph 2015 and Globinmed website (http://www.globinmed.com/). An extensive bibliographic search in databases such as PubMed, ScienceDirect, and Scopus revealed that seven of these plants have antisepsis properties, as evidenced by the therapeutic effect of their extracts or isolated compounds against sepsis-associated inflammatory responses or conditions in in vitro or/and in vivo studies. These include Andrographis paniculata, Zingiber officinale, Curcuma longa, Piper nigrum, Syzygium aromaticum, Momordica charantia, and Centella asiatica. Among these, Z. officinale is the most widely studied plant and seems to have the highest potential for future therapeutic applications in sepsis. Although both extracts as well as active constituents from these herbal plants have demonstrated potential antisepsis activity, the activity might be primarily contributed by the active constituent(s) from each of these plants, which are andrographolide (A. paniculata), 6-gingerol and zingerone (Z. officinale), curcumin (C. longa), piperine and pellitorine (P. nigrum), biflorin (S. aromaticum), and asiaticoside, asiatic acid, and madecassoside (C. asiatica). These active constituents have shown great antisepsis effects, and further investigations into their clinical therapeutic potential may be worthwhile.

Dual Effect of Soloxolone Methyl on LPS-Induced Inflammation In Vitro and In Vivo

Plant-extracted triterpenoids belong to a class of bioactive compounds with pleotropic functions, including antioxidant, anti-cancer, and anti-inflammatory effects. In this work, we investigated the anti-inflammatory and anti-oxidative activities of a semisynthetic derivative of 18βH-glycyrrhetinic acid (18βH-GA), soloxolone methyl (methyl 2-cyano-3,12-dioxo-18βH-olean-9(11),1(2)-dien-30-oate, or SM) in vitro on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and in vivo in models of acute inflammation: LPS-induced endotoxemia and carrageenan-induced peritonitis. SM used at non-cytotoxic concentrations was found to attenuate the production of reactive oxygen species and nitric oxide (II) and increase the level of reduced glutathione production by LPS-stimulated RAW264.7 cells. Moreover, SM strongly suppressed the phagocytic and migration activity of activated macrophages. These effects were found to be associated with the stimulation of heme oxigenase-1 (HO-1) expression, as well as with the inhibition of nuclear factor-κB (NF-κB) and Akt phosphorylation. Surprisingly, it was found that SM significantly enhanced LPS-induced expression of the pro-inflammatory cytokines interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) in RAW264.7 cells via activation of the c-Jun/Toll-like receptor 4 (TLR4) signaling axis. In vivo pre-exposure treatment with SM effectively inhibited the development of carrageenan-induced acute inflammation in the peritoneal cavity, but it did not improve LPS-induced inflammation in the endotoxemia model.

Soluble cluster of differentiation 74 regulates lung inflammation through the nuclear factor-κB signaling pathway

The soluble form of the migration inhibitory factor receptor cluster of differentiation 74 (sCD74) has previously been shown to be elevated during the development of acute lung injury (ALI) in mice. However, the biological role of increased sCD74 in ALI remans poorly understood. Synthesized recombinant sCD74 protein was administered to mice intratracheally. Pro-inflammatory genes in lung tissue and the inflammatory factors in bronchoalveolar lavage fluid (BALF) were analyzed using RT-PCR and ELISA, respectively. Additionally, RAW264.7, A549, and human umbilical vein endothelial cells (HUVEC) were treated with sCD74, and the resulting pro-inflammatory factor protein and gene expression levels were analyzed in the supernatants and cell lysates. Meanwhile, the level of nuclear factor (NF)-κB components in cell lysates after stimulating macrophages with sCD74 was also assessed. After administration of 0.5 mg/kg body weight sCD74 to mice, the expression of Tnfa, Mip2, and Il6 increased in lung tissues after 2 h by 2.1-, 3.4-, and 2.8-fold, respectively. Moreover, the BALF concentrations of TNF-α and MIP-2 reached maximal levels of 560 and 107 pg/mL at 8 h compared to those in the saline group, respectively. Similarly, TNFA, MIP2, and IL6 expression increased by 4.0-, 11.8-, and 2.6-fold, respectively, 2 h after stimulating macrophages with 1000 ng/mL sCD74. The levels of phospho-IκB and phospho-p65 were also significantly increased in the cytoplasm and nucleus of macrophages following sCD74 stimulation. Taken together, these results suggest that sCD74 is a critical cellular factor involved in the lung acute inflammatory response through nuclear factor-κB signaling.

Phytotherapy in endometriosis: an up-to-date review

Endometriosis is a benign gynecological disease which symptoms can provide a severe impact on patient's quality of life with subsequent impact on psychological well-being. Different therapeutic strategies are available to treat this disease, such as surgery, hormonal therapies, and nonsteroidal anti-inflammatory drugs. Nevertheless, the efficacy of conventional medical treatments is limited or intermittent in most of the patients due to the associated side effects. Therefore, a woman with endometriosis often search for additional and alternative options, and phytotherapy might be a promising alternative and complementary strategy. Different medicinal plants, multicomponent herbal preparations, and phytochemicals were investigated for pharmacological proprieties in endometriosis therapy. In most of the cases, the effect on endometriosis was related to phenolic compounds, such as flavonoids and phenolic acids reporting anti-inflammatory, proapoptotic, antioxidant, and immunomodulatory functions. Moreover, some phytochemicals have been related to a strong phytoestrogenic effect modulating the estrogen activity. Although promising, available evidence is based on in vitro and animal models of endometriosis with a limited number of well-performed clinical studies. There are almost none randomized control trials in this area. Therefore, properly constructed clinical trials are mandatory to achieve more conclusive results about the promising role of phytotherapy in the management of endometriosis.

Astaxanthin suppresses lipopolysaccharide‑induced myocardial injury by regulating MAPK and PI3K/AKT/mTOR/GSK3β signaling

Cardiac dysfunction is a significant manifestation of sepsis and it is associated with the prognosis of the disease. Astaxanthin (ATX) has been discovered to serve a variety of pharmacological effects, including anti‑inflammatory, antioxidant and antiapoptotic properties. The present study aimed to investigate the role and mechanisms of ATX in sepsis‑induced myocardial injury. Male C57BL/6 mice were divided into three groups (15 mice per group): Control group, lipopolysaccharide (LPS) group and LPS + ATX group. The cardiac dysfunction model was induced through an intraperitoneal injection of LPS (10 mg/kg) and ATX (40 mg/kg) was administered to the LPS + ATX group by intraperitoneal injection 30 min following the administration of LPS. All animals were sacrificed after 24 h. Inflammatory cytokine levels in the serum were detected using ELISAs, and cardiac B‑type natriuretic peptide (BNP) levels were analyzed using western blot analysis and reverse transcription‑quantitative PCR. Furthermore, the extent of myocardial injury was evaluated using pathological analysis, and cardiomyocyte apoptosis was analyzed using a TUNEL assay, in addition to determining the expression levels of Bcl‑2 and Bax. The expression levels of proteins involved in the mitogen activated protein kinase (MAPK) and PI3K/AKT signaling pathways were also analyzed using western blot analysis. ATX significantly suppressed the LPS‑induced increased production of TNF‑α and IL‑6 and suppressed the protein expression levels of BNP, Bax and Bcl‑2 to normal levels. ATX also prevented the histopathological changes to the myocardial tissue and reduced the extent of necrosis. Furthermore, the treatment with ATX suppressed the LPS‑activated MAPK and PI3K/AKT signaling. ATX additionally exerted a protective effect on cardiac dysfunction caused by sepsis by inhibiting MAPK and PI3K/AKT signaling.

Curcumin analogs (B2BrBC and C66) supplementation attenuates airway hyperreactivity and promote airway relaxation in neonatal rats exposed to hyperoxia

BACKGROUND

This study was undertaken to test the hypothesis that the newly synthesized curcuminoids B2BrBC and C66 supplementation will overcome hyperoxia-induced tracheal hyperreactivity and impairment of relaxation of tracheal smooth muscle (TSM).

MATERIALS AND METHODS

Rat pups (P5) were exposed to hyperoxia (>95% O2 ) or normoxia for 7 days. At P12, tracheal cylinders were used to study in vitro contractile responses induced by methacholine (10-8 -10-4 M) or relaxation induced by electrical field stimulation (5-60 V) in the presence/absence of B2BrBC or C66, or to study the direct relaxant effects elicited by both analogs.

RESULTS

Hyperoxia significantly increased contraction and decreased relaxation of TSM compared to normoxia controls. Presence of B2BrBC or C66 normalized both contractile and relaxant responses altered by hyperoxia. Both, curcuminoids directly induced dose-dependent relaxation of preconstricted TSM. Supplementation of hyperoxic animals with B2BrBC or C66, significantly increased catalase activity. Lung TNF-α was significantly increased in hyperoxia-exposed animals. Both curcumin analogs attenuated increases in TNF-α in hyperoxic animals.

CONCLUSION

We show that B2BrBC and C66 provide protection against adverse contractility and relaxant effect of hyperoxia on TSM, and whole lung inflammation. Both analogs induced direct relaxation of TSM. Through restoration of catalase activity in hyperoxia, we speculate that analogs are protective against hyperoxia-induced tracheal hyperreactivity by augmenting H2 O2 catabolism. Neonatal hyperoxia induces increased tracheal contractility, attenuates tracheal relaxation, diminishes lung antioxidant capacity, and increases lung inflammation, while monocarbonyl CUR analogs were protective of these adverse effects of hyperoxia. Analogs may be promising new therapies for neonatal hyperoxic airway and lung disease.

Polymyxins-Curcumin Combination Antimicrobial Therapy: Safety Implications and Efficacy for Infection Treatment

The emergence of antimicrobial resistance in Gram-negative bacteria poses a huge health challenge. The therapeutic use of polymyxins (i.e., colistin and polymyxin B) is commonplace due to high efficacy and limiting treatment options for multidrug-resistant Gram-negative bacterial infections. Nephrotoxicity and neurotoxicity are the major dose-limiting factors that limit the therapeutic window of polymyxins; nephrotoxicity is a complication in up to ~60% of patients. The emergence of polymyxin-resistant strains or polymyxin heteroresistance is also a limiting factor. These caveats have catalyzed the search for polymyxin combinations that synergistically kill polymyxin-susceptible and resistant organisms and/or minimize the unwanted side effects. Curcumin—an FDA-approved natural product—exerts many pharmacological activities. Recent studies showed that polymyxins–curcumin combinations showed a synergistically inhibitory effect on the growth of bacteria (e.g., Gram-positive and Gram-negative bacteria) in vitro. Moreover, curcumin co-administration ameliorated colistin-induced nephrotoxicity and neurotoxicity by inhibiting oxidative stress, mitochondrial dysfunction, inflammation and apoptosis. In this review, we summarize the current knowledge-base of polymyxins–curcumin combination therapy and discuss the underlying mechanisms. For the clinical translation of this combination to become a reality, further research is required to develop novel polymyxins–curcumin formulations with optimized pharmacokinetics and dosage regimens.

Patriscabrin F from the roots of Patrinia scabra attenuates LPS-induced inflammation by downregulating NF-κB, AP-1, IRF3, and STAT1/3 activation in RAW 264.7 macrophages

BACKGROUND

The roots of Partrinia scabra have been used as a medicinal herb in Asia. We previously reported that the inhibitory effect of patriscabrin F on lipopolysaccharide (LPS)-induced nitric oxide (NO) production was the most potent than that of other isolated iridoids from the roots of P. scabra.

PURPOSE

We investigated the anti-inflammatory activity of patriscabrin F as an active compound of P. scabra and related signaling cascade in LPS-activated macrophages.

METHOD

The anti-inflammatory activities of patriscabrin F were determined according to its inhibitory effects on NO, prostaglandin E₂ (PGE₂), and pro-inflammatory cytokines. The molecular mechanisms were revealed by analyzing nuclear factor-κB (NF-κB), activator protein-1 (AP-1), interferon regulatory factor 3 (IRF3), and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway.

RESULTS

Patriscabrin F inhibited the LPS-induced production of NO, PGE_2, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 in both bone-marrow derived macrophages (BMDMs) and RAW 264.7 macrophages. Patriscabrin F downregulated LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), TNF-α, IL-1β, and IL-6 at the transcriptional level. Patriscabrin F suppressed LPS-induced NF-κB activation by decreasing p65 nuclear translocation, inhibitory κBα (IκBα) phosphorylation, and IκB kinase (IKK)α/β phosphorylation. Patriscabrin F attenuated LPS-induced AP-1 activity by inhibiting c-Fos phosphorylation. Patriscabrin F suppressed the LPS-induced phosphorylation of IRF3, JAK1/JAK2, and STAT1/STAT3.

CONCLUSION

Taken together, our findings suggest patriscabrin F may exhibit anti-inflammatory properties via the inhibition of NF-κB, AP-1, IRF3, and JAK-STAT activation in LPS-induced macrophages.

Reactive oxygen species-responsive dexamethasone-loaded nanoparticles for targeted treatment of rheumatoid arthritis via suppressing the iRhom2/TNF-α/BAFF signaling pathway

Rheumatoid arthritis (RA) is an immune-mediated inflammatory disease that results in synovitis, cartilage destruction, and even loss of joint function. The frequent and long-term administration of anti-rheumatic drugs often leads to obvious adverse effects and patient non-compliance. Therefore, to specifically deliver dexamethasone (Dex) to inflamed joints and reduce the administration frequency of Dex, we developed Dex-loaded reactive oxygen species (ROS)-responsive nanoparticles (Dex/Oxi-αCD NPs) and folic acid (FA) modified Dex/Oxi-αCD NPs (Dex/FA-Oxi-αCD NPs) and validated their anti-inflammatory effect in vitro and in vivo. In vitro study demonstrated that these NPs can be effectively internalized by activated macrophages and the released Dex from NPs significantly downregulated the expression of iRhom2, TNF-α, and BAFF in activated Raw264.7. In vivo experiments revealed that Dex/Oxi-αCD NPs, especially Dex/FA-Oxi-αCD NPs significantly accumulated at inflamed joints in collagen-induced arthritis (CIA) mice and alleviated the joint swelling and cartilage destruction. Importantly, the expression of iRhom2, TNF-α, and BAFF in the joint was inhibited by intravenous injection of Dex/Oxi-αCD NPs and Dex/FA-Oxi-αCD NPs. Collectively, our data revealed that Dex-loaded ROS-responsive NPs can target inflamed joints and attenuate arthritis, and the 'iRhom2-TNF-α-BAFF' pathway plays an important role in the treatment of RA with the NPs, suggesting that this pathway may be a novel target for RA therapy.

Effects of treatment with gold nanoparticles in a model of acute pulmonary inflammation induced by lipopolysaccharide

The bacterial lipopolysaccharide (LPS) is a highly toxic molecule derived from the outer membrane of gram-negative bacteria. LPS endotoxin affects the lungs and is used as a model of acute pulmonary inflammation affecting the cellular morphology of the organ. Previously, gold nanoparticles (GNPs) have been shown to demonstrate anti-inflammatory and antioxidative activity in muscle and epithelial injury models. The objective of this study was to investigate the effect of the intraperitoneal treatment using GNPs on the inflammatory response and pulmonary oxidative stress induced by LPS. Wistar rats were divided into four groups (N = 10): Sham; Sham + GNPs 2.5 mg/kg; LPS; and LPS + GNPs 2.5 mg/kg. Treatment with LPS upregulated the levels of markers of cellular and hepatic damage (CK, LDH, AST, and alanine aminotransferase); however, the group treated with only GNPs exhibited no toxicity. Treatment with GNPs reversed LPS-induced changes with respect to total peritoneal leukocyte count and the pulmonary levels of pro-inflammatory cytokines (IFN-γ and IL-6). Histological analysis revealed that treatment with GNPs reversed the increase in alveolar septum thickness due to LPS-induced fibrosis. In addition, treatment with GNPs decreased production of oxidants (nitrite and DCFH), reduced oxidative damage (carbonyl and sulfhydryl), and downregulated activities of superoxide dismutase and catalase. Treatment with GNPs did not showed toxicity; however, it exhibited anti-inflammatory and antioxidative activity that reversed morphological alterations induced by LPS.

Therapeutic effects of curcumin on sepsis and mechanisms of action: A systematic review of preclinical studies

Sepsis is a complex disease that begins with an infectious disorder and causes excessive immune responses. Curcumin is considered as an active component of turmeric that can improve the condition in sepsis due to its anti-inflammatory and antioxidant properties. PubMed, Embase, Google Scholar, Web of Science, and Scopus databases were searched. Searching was not limited to a specific publication period. Only English-language original articles, which had examined the effect of curcumin on sepsis, were included. At first, 1,098 articles were totally found, and 209 articles were selected after excluding duplicated data; 46 articles were remained due to the curcumin effects on sepsis. These included 23 in vitro studies and 23 animal studies. Our results showed that curcumin and various analogs of curcumin can have an inhibitory effect on sepsis-induced complications. Curcumin has the ability to inhibit the inflammatory, oxidative coagulation factors, and regulation of immune responses in sepsis. Despite the promising evidence of the therapeutic effects of curcumin on the sepsis complication, further studies seem necessary to investigate its effect and possible mechanisms of action in human studies.

Combined delivery of curcumin and the heme oxygenase-1 gene using cholesterol-conjugated polyamidoamine for anti-inflammatory therapy in acute lung injury

BACKGROUND

Acute lung injury (ALI) is an inflammatory lung disease with a high mortality rate. In this study, combined delivery of the anti-inflammatory compound curcumin and the heme-oxygenase-1 (HO-1) gene using cholesterol-conjugated polyamidoamine was evaluated in a mouse model as a therapeutic option for ALI.

METHODS

Curcumin was loaded into cholesterol-conjugated polyamidoamine (PamChol) micelles, and curcumin-loaded PamChol (PamChol-Cur) was then complexed with plasmid DNA (pDNA) through charge interactions. The pDNA/PamChol-Cur complex was physically characterized by dynamic light scattering, gel retardation, and heparin competition assay. Gene delivery efficiency was measured by luciferase assay. The HO-1 expression plasmid (pHO-1)/PamChol-Cur complex was administrated into the ALI model via intratracheal injection. The anti-inflammatory effect of the pDNA/PamChol-Cur complex was evaluated by ELISA, immunohistochemistry, and hematoxylin and eosin staining.

RESULTS

The pDNA/PamChol-Cur complex had a size of approximately 120 nm with a positive surface charge. The in vitro plasmid DNA (pDNA) delivery efficiency of the pDNA/PamChol-Cur complex into L2 lung epithelial cells was higher than that of pDNA/PamChol. In addition, the curcumin in the pDNA/PamChol-Cur complex inhibited the nuclear translocation of NF-κB, suggesting an anti-inflammatory effect of curcumin. In the ALI animal model, the pHO-1/PamChol-Cur complex delivered the pHO-1 gene more efficiently than pHO-1/PamChol. In addition, the pHO-1/PamChol-Cur complex showed greater anti-inflammatory effects by reducing anti-inflammatory cytokine levels more than delivery of pHO-1/PamChol or PamChol-Cur only.

CONCLUSION

The pHO-1/PamChol-Cur complex had a higher pHO-1 gene-delivery efficiency and greater anti-inflammatory effects than the pHO-1/PamChol complex or PamChol-Cur. Therefore, the combined delivery of curcumin and pHO-1 using PamChol-Cur may be useful for treatment of ALI.

Intranasal curcumin protects against LPS-induced airway remodeling by modulating toll-like receptor-4 (TLR-4) and matrixmetalloproteinase-9 (MMP-9) expression via affecting MAP kinases in mouse model

OBJECTIVE

Bacterial infections can exacerbate asthmatic inflammation depending on lipopolysaccharide (LPS) composition, the outermost component of cell wall, its exposure timings as well as host's immune status. In present study, Balb/c mice were exposed to antigen (ovalbumin) and LPS simultaneously to establish an asthmatic model. Curcumin (diferuloylmethane), well known for its anti-inflammatory potential, was administered through intranasal route 1 h before LPS and OVA (ovalbumin) exposure to evaluate its efficacy against airway structural changes.

METHODS

Inflammatory cell infiltration in lungs was measured by flow cytometry and further eosinophils were especially measured by immunofluorescence detection of major basic protein (MBP) as marker of eosinophilc granule protein. We also measured reactive oxygen species (ROS) in BALF by spectrofluorometry. MMP-9 activity was evaluated by gelatin zymography and mRNA expressions of MMP-9, TIMP-1, TGF-β1, IL-13, Collagen-1 and TLR-4 were measured in lungs. Protein expression of MAP kinases (P-ERK, P-JNK, P-p38), TLR-4, Cox-2, Lox-5 and Eotaxin was measured by western blotting. Hydroxyproline level and masson's trichrome staining were used to evaluate collagen deposition in lung.

RESULTS

Exposure to LPS (0.1 µg) exacerbates airway inflammation and induces structural changes in lungs by enhanced ROS production, collagen deposition, expression of genes involved in airway remodeling and activation of MAP kinases pathway enzymes. Intranasal curcumin pretreatment had significantly suppressed inflammatory mediators and airway remodeling proteins.

CONCLUSION

Our results strongly suggest that intranasal curcumin effectively protects LPS-induced airway inflammation and structural changes by modulating genes involved in airway remodeling in safer way; hence, it can be considered as supplementary alternative towards asthma treatments.

Plant-derived medicines for treatment of endometriosis: A comprehensive review of molecular mechanisms

Endometriosis is an estrogen-dependent disease with inflammatory lesions at extra-uterine sites, causing pelvic pain and fertility reduction. Conventional therapies primarily focus on reducing systemic levels of estrogens; however, they do not have desirable effectiveness and possess considerable side effects. Therefore, there is a growing interest in the use of herbal medicine for the treatment of endometriosis. In this paper, electronic databases including PubMed, Scopus, Cochrane library and Google Scholar were searched to obtain any studies evaluating any herbal products in the management of endometriosis. Data were collected from 1980 to 2018. Most of studies investigating the effect of herbal medicines in endometriosis were in vitro and animal and only three clinical trials were found; one on Pinus pinaster bark extract (Pycnogenol) and two on Chinese herbal formulas. The studies on phytochemicals had mostly focused on polyphenolic compounds (epigallocatechin-3-gallate, genistein) and sesquiterpenes (β-caryophyllene, parthenolide). Various molecular mechanisms of action have been involved in beneficial effects of herbal medicines and phytochemicals including anti-inflammatory (via reduction of proinflammatory cytokines such as interleukin -1, interleukin -6, interleukin -8, transforming growth factor-beta, tumor necrosis factor-α, nuclear factor-kappa B, growth factors, monocyte chemoattractant protein-1), antioxidant (through downregulation of hydrogen peroxide, malondialdehyde, reactive oxygen species and upregulation of superoxide dismutase), anti-proliferative and apoptotic (via enhancing Bcl-2-associated X protein/ B-cell lymphoma-2 and caspase3, 8 and 9 activity), anti-angiogenic (by downregulation of vascular endothelial growth factor receptors/ vascular endothelial growth factor), anti-invasive (via decreasing expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1 and matrix metalloproteinases), immunomodulatory, and estrogen modulating activities. So, medicinal plants seem to be a valuable source for identifying new drugs for treatment of endometriosis; however, since most of studies are preclinical, further clinical trials are required to achieve more conclusive results.

Modulators of inflammation in Bronchopulmonary Dysplasia

Over 50 years after its first description, Bronchopulmonary Dysplasia (BPD) remains a devastating pulmonary complication in preterm infants with respiratory failure and develops in 30-50% of infants less than 1000-gram birth weight. It is thought to involve ventilator- and oxygen-induced damage to an immature lung that results in an inflammatory response and ends in aberrant lung development with dysregulated angiogenesis and alveolarization. Significant morbidity and mortality are associated with this most common chronic lung disease of childhood. Thus, any therapies that decrease the incidence or severity of this condition would have significant impact on morbidity, mortality, human costs, and healthcare expenditure. It is clear that an inflammatory response and the elaboration of growth factors and cytokines are associated with the development of BPD. Numerous approaches to control the inflammatory process leading to the development of BPD have been attempted. This review will examine the anti-inflammatory approaches that are established or hold promise for the prevention or treatment of BPD.

Inflammatory mechanisms and oxidative stress in prostatitis: the possible role of antioxidant therapy

This article focuses on the role that oxidative stress plays in chronic prostatitis, not only with respect to the known impact on symptoms and fertility but also especially in relation to possible prostate cancer development. Prostatitis is the most common urologic disease in adult males younger than 50 years and the third most common urologic diagnosis in males older than 50 years. If the germ-causing acute prostatitis is not eliminated, the inflammatory process becomes chronic. Persistent inflammation causes ongoing production of large quantities of pro-inflammatory cytokines and both oxygen and nitrogen reactive species, with consequent activation of transcription factor nuclear factor-kappa B (NF-κB) and genes encoding for further production of pro-inflammatory cytokines, chemotactic factors, and growth factors. Confirming the role of oxidative stress in chronic prostatitis, several studies have demonstrated the presence of oxidative stress markers in the genital secretions of patients suffering from the disease. Antioxidants can therefore play an essential role in the treatment of chronic bacterial and non-bacterial prostatitis; in the case of bacterial inflammation, they can be associated with antibiotic therapy. Moreover, due to their anti-inflammatory properties, antioxidants hinder the progression of inflammation and the possible development of prostate cancer.

Fungal-Host Interaction: Curcumin Modulates Proteolytic Enzyme Activity of Candida albicans and Inflammatory Host Response In Vitro

Current treatments for Candida albicans infection are limited due to the limited number of antifungal drugs available and the increase in antifungal resistance. Curcumin is used as a spice, food preservative, flavoring, and coloring agent that has been shown to have many pharmacological activities. Thus, this study evaluated the modulatory effects of curcumin on major virulence factors associated with the pathogenicity of C. albicans. The minimum inhibitory concentration (MIC) of curcumin against C. albicans (SC5314) was determined. Biofilm formation was quantified and the proteinase and phospholipase secretion was measured. The cytotoxicity was tested in oral fibroblast cells. A cocultured model was used to analyze the gene expression of proinflammatory cytokines (IL-1β, IL-1α, and IL-6) from host cells, as well SAP-1 and PLB-1 by RT-PCR. The MIC was between 6.25 and 12.5 µM, and the activity of proteinase enzyme was significantly decreased in biofilms treated with curcumin. However, proteinase gene expression was not downregulated after curcumin treatment. Furthermore, gene expressions of host inflammatory response, IL-1β and IL-1α, were significantly downregulated after exposure to curcumin. In conclusion, curcumin exhibited antifungal activity against C. albicans and modulated the proteolytic enzyme activities without downregulating the gene expression. In host inflammatory response, curcumin downregulated IL-1β and IL-1α gene expression.

The Endotoxemia Marker Lipopolysaccharide-Binding Protein is Reduced in Overweight-Obese Subjects Consuming Pomegranate Extract by Modulating the Gut Microbiota: A Randomized Clinical Trial

SCOPE

Gut microbiota dysbiosis, intestinal barrier failure, obesity, metabolic endotoxemia, and pro-inflammatory status promote cardiovascular risk. However, the modulation of the gut microbiome to prevent endotoxemia in obesity has been scarcely studied. We investigated the association between gut microbiota modulation and plasma lipopolysaccharide-binding protein (LBP), a surrogate marker of endotoxemia, in overweight-obese individuals.

METHODS AND RESULTS

In a randomized trial, 49 overweight-obese subjects (body mass index> 27 kg m^-2 ) with mild hypelipidemia daily consumed, in a cross-over fashion, two doses (D1 and D2, lasting 3 weeks each) of pomegranate extract (PE) or placebo alternating with 3 weeks of wash-out periods. A significant decrease (p < 0.05) of plasma LBP and a marginal decrease (p = 0.054) of high-sensitivity C-reactive protein were observed, but only after PE-D2 administration (656 mg phenolics). 16S rDNA sequencing analyses revealed the increase of microorganisms important for maintaining normal balance of gut microbiota and gut barrier function, particularly Bacteroides, Faecalibacterium, Butyricicoccus, Odoribacter, and Butyricimonas. PE-D2 also decreased pro-inflammatory microorganisms including Parvimonas, Methanobrevibacter, and Methanosphaera. Remarkably, plasma LBP reduction was significantly associated (p < 0.05) with both Faecalibacterium and Odoribacter increase and Parvimonas decrease.

CONCLUSIONS

Consumption of PE decreased endotoxemia in overweight-obese individuals by reshaping the gut microbiota, mainly through the modulation of Faecalibacterium, Odoribacter, and Parvimonas.

Atractylenolide Ⅰ protects against lipopolysaccharide-induced disseminated intravascular coagulation by anti-inflammatory and anticoagulation effect

OBJECTIVE

To investigate whether atractylenolide Ⅰ (ATL-Ⅰ) has protective effect on lipopolysaccharide (LPS)-induced disseminated intravascular coagulation (DIC) in vivo and in vitro, and explore whether NF-κB signaling pathway is involved in ATL-Ⅰ treatment.

METHODS

New Zealand white rabbits were injected with LPS through marginal ear vein over a period of 6 h at a rate of 600 μg/kg (10 mL/h). Similarly, in the treatment groups, 1.0, 2.0, or 5.0 mg/kg ATL-Ⅰ were given. Both survival rate and organ function were tested, including the level of alanine aminotransferase (ALT), blood urine nitrogen (BUN), and TNF-α were examined by ELISA. Also hemostatic and fibrinolytic parameters in serum were measured. RAW 264.7 macrophage cells were administered with control, LPS, LPS + ATL-Ⅰ and ATL-Ⅰ alone, and TNF-α, phosphorylation (P)-IκBα, phosphorylation (P)-NF-κB (P65) and NF-κB (P65) were determined by Western blot.

RESULTS

The administration of LPS resulted in 73.3% mortality rate, and the increase of serum TNF-α, BUN and ALT levels. When ATL-Ⅰ treatment significantly increased the survival rate of LPS-induced DIC model, also improved the function of blood coagulation. And protein analysis indicated that ATL-I remarkably protected liver and renal as decreasing TNF-α expression. In vitro, ATL-I obviously decreased LPS-induced TNF-α production and the expression of P-NF-κB (P65), with the decrease of P-IκBα.

CONCLUSIONS

ATL-Ⅰ has protective effect on LPS-induced DIC, which can elevate the survival rate, reduce organ damage, improve the function of blood coagulation and suppress TNF-α expression by inhibiting the activation of NF-κB signaling pathway.