Turmerone enriched standardized Curcuma longa extract alleviates LPS induced inflammation and cytokine production by regulating TLR4–IRAK1–ROS–MAPK–NFκB axis

Anti-inflammatory potential of Piper betleoides C. DC., a promising Piper species of Northeast India: in vitro and in vivo evidence and mechanistic insight

The present study aims to investigate the anti-inflammatory potential of the leaf hydroalcoholic extract of Piper betleoides C. DC., also known as "Jangli Paan" in Northeast India, using lipopolysaccharide (LPS)-treated both cell culture (RAW264.7, macrophage cells) and animal (albino rat) model of inflammation. Treatment with leaf hydroalcoholic extract of Piper betleoides (PBtE) dose-dependently (5, 10, and 20 µg/mL) decreased the secretion of pro-inflammatory (TNF-α, IL-6, and MCP-1) and increased anti-inflammatory (IL-4 and IL-10) cytokines in LPS-treated macrophages. Similarly, treatment with PBtE also prevented the alternation in mRNA expression of inflammatory markers (TNF-α, CCL-2, IL-6, and IL-10) in LPS-treated macrophages. Dose-dependent supplementation with PBtE further reduced the production of intracellular ROS and increased the phagocytosis efficacies in LPS-treated cells. Further in vivo studies demonstrated that treatment with PBtE dose-dependently (50, 100, and 200 mg/kg body weight) prevented the dysregulation of the secretion of inflammatory cytokines (TNF-α, IL-4, IL-6, and IL-10) and reduced the circulatory levels of prostaglandin (PGE2) and nitric oxide products (nitrite) in LPS-treated animals. In addition, alternation of blood cell profiling and the liver as well as kidney dysfunctions were also prevented by the treatment with PBtE in LPS-treated rats. The anti-inflammatory potential of PBtE was comparable to those seen in sodium diclofenac (positive control) treated group. LC-MS analyses showed piperine, piperlongumine, piperolactam-A, and dehydropipernonaline and GC-MS analyses demonstrated phytol, caryophyllene, and falcarinol as the phytochemicals present in Piper betleoides, which might play an important role in preventing inflammation and associated pathophysiology. Different treatments didn't cause any toxicity in cell culture and animal models. This study for the first time demonstrated the promising anti-inflammatory potential of the leaf hydroalcoholic extract of Piper betleoides.

Synergistic Inhibition of Pro-Inflammatory Pathways by Ginger and Turmeric Extracts in RAW 264.7 Cells

Synergy plays a prominent role in herbal medicines to increase potency and widen the therapeutic windows. The mechanism of synergy in herbal medicines is often associated with multi-targeted behavior and complex signaling pathways which are challenging to elucidate. This study aims to investigate the synergistic mechanism of a combination (GT) of ginger (G) and turmeric (T) extracts by exploring the modulatory activity in lipopolysaccharides (LPS)-induced inflammatory pathways and key molecular targets. A Bioplex ProTM mouse cytokine 23-plex assay was utilized to assess the broad anti-cytokine activity of GT in LPS and interferon (IFN)-ɣ (both at 50 ng/mL)-activated RAW 264.7 cells. The inhibitory effects of individual and combined G and T on major proinflammatory mediators including nitric oxide (NO), tumor necrosis factor (TNF) and interleukin (IL)-6 were tested using Griess reagents and ELISA assays, respectively. Immunofluorescent staining and Western blot were used to investigate the modulatory effect of GT on key proteins in the LPS/TLR4 signaling transduction. The regulation of murine microRNA miR-155-5p was tested using real-time PCR. The IC50 value and combination index (CI) values were used to demonstrate potency and synergistic interaction, respectively. GT synergistically attenuated a range of pro-inflammatory mediators including inducible NO, major cytokines (TNF and IL-6) and secondary inflammatory cytokines (GM-CSF and MCP-1). GT significantly inhibited LPS-induced NF-kB p65 translocation, the activation of TLR4, TRAF6, and phosphorylation of JNK and c-JUN. Moreover, the suppressive effect of GT on each of the protein targets in this axis was stronger than that of the individual components. Real-time PCR analysis showed that GT suppressed miR-155-5p to a greater extent than G or T alone in LPS-stimulated cells. Our study demonstrates the synergistic mechanism of GT in downregulating LPS-induced proinflammatory pathways at the miRNA and protein levels. Our results establish a scientific basis for the combined application of G and T as an advanced therapeutic candidate in inflammatory diseases with broad and synergistic anti-inflammatory activity and multi-targeted mechanisms.

Turmeric and its bioactive constituents trigger cell signaling mechanisms that protect against diabetes and cardiovascular diseases

Turmeric, the rhizome of Curcuma longa plant belonging to the ginger family Zingiberaceae, has a history in Ayurvedic and traditional Chinese medicine for treatment of chronic diseases, including metabolic and cardiovascular diseases (CVD). This parallels a prevalence of age- and lifestyle-related diseases, especially CVD and type 2 diabetes (T2D), and associated mortality which has occurred in recent decades. While the chemical composition of turmeric is complex, curcuminoids and essential oils are known as two major groups that display bioactive properties. Curcumin, the most predominant curcuminoid, can modulate several cell signaling pathways involved in the etiology and pathogenesis of CVD, T2D, and related morbidities. Lesser bioactivities have been reported from other curcuminoids and essential oils. This review examines the chemical compositions of turmeric, and related bioactive constituents. A focus was placed on the cellular and molecular mechanisms that underlie the protective effects of turmeric and turmeric-derived compounds against diabetes and CVD, compiled from the findings obtained with cell-based and animal models. Evidence from clinical trials is also presented to identify potential preventative and therapeutic efficacies. Clinical studies with longer intervention durations and specific endpoints for assessing health outcomes are warranted in order to fully evaluate the long-term protective efficacy of turmeric.

The Genus Curcuma and Inflammation: Overview of the Pharmacological Perspectives

The Curcuma genus has been extensively used for therapeutic purposes in traditional or folk medicine worldwide, including for its anti-inflammatory activity. Curcuma spp.'s active constituents, such as alkaloids, flavonoids, and terpenoids, can act on various targets in the signaling pathway, restrain pro-inflammatory enzymes, lower the production of inflammatory cytokines and chemokines, and reduce oxidative stress, which subsequently suppresses inflammatory processes. Preclinical and clinical studies have reported the predominant anti-inflammatory activity of several Curcuma species. This review provides an overview of the anti-inflammatory effects of different extracts, preparations, and bioactive components in this genus. This analysis may provide a scientific basis for developing new and alternative methods for the isolation of a single entity from this genus to attenuate inflammatory conditions. The Curcuma genus is waiting for researchers interested in developing safe and efficient anti-inflammatory agents for further investigation.

Determination of Curcuma longa L. (Turmeric) Leaf Extraction Conditions Using Response Surface Methodology to Optimize Extraction Yield and Antioxidant Content

Curcuma longa L. (turmeric) has been used as a functional food material, but other parts of it such as leaves are wasted as a byproduct. This work concentrated on developing turmeric leaves as a functional food material by establishing its optimal extraction condition. Response surface methodology was applied to optimize turmeric leaf extraction conditions. Turmeric leaves were pulled out with water and ethanol (10, 30, and 50%). Then, total phenolic compound content, total flavonoid content, and radical-scavenging activity of each extract were quantified to confirm the optimal extracting solvent. According to the results, water was the most efficient solvent to extract antioxidant contents such as total phenolic compounds (3.65 ± 0.02 mg GAE/g) and flavonoids (4.99 ± 0.17 mg QCE/g) content. Radical-scavenging activity was also higher in water extract compared with others such as DPPH (51.10 ± 2.29%), H2O2 (25.39 ± 2.69%), and ABTS (91.08 ± 0.15%). Central composite design was applied to confirm the effect of independent variables such as temperature (X1) and time (X2) to the yield (Y1). After conducting experiments, the extraction condition was established as 150 min with 1 : 25 ratio at 85°C with a 15.58% yield. Proximate compositions of the extract were determined to suggest background data for further research. In conclusion, this study confirmed the antioxidant property of turmeric leaves and developed the optimal extraction condition of the leaves to promote its application in food industry as a new food source.

Changes of Th17/Treg ratio in the transition of chronic hepatitis B to liver cirrhosis and correlations with liver function and inflammation

The changes in ratio of T helper 17 cells (Th17) to Treg cells in the transition of chronic hepatitis B (CHB) to liver cirrhosis, and the correlations with liver function and inflammation were investigated. A total of 20 normal subjects (control group), 35 CHB patients (CHB group) and 40 post-hepatitis liver cirrhosis patients (liver cirrhosis group) were enrolled into this study. Liver function was measured through the levels of alanine aminotransferase (ALT) and aspartic transaminase (AST), and the hematoxylin and eosin (H&E) staining method was used to detect the histopathological features. mRNA expression of inflammation-associated factors was detected using RT-PCR. The protein expression of nuclear factor κB (NF-κB) was measured in liver tissues using the immunofluorescent method and western blot assay. In the CHB and liver cirrhosis groups, the increases in Th17 cells were more evident than those in Treg cells. Moreover, an evident increase in levels of ALT and AST was identified in the two groups. Structures of liver tissues in the CHB and liver cirrhosis groups were destroyed with damage to the cell nuclei. The expression of inflammation-associated factors were significantly elevated compared to those in the control group. NF-κB expressed in the CHB and liver cirrhosis groups was significantly higher than that in control group. The results of analysis of variance indicated that differences in the expression of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α and NF-κB in the three groups had statistical significance (P<0.01). In conclusion, transition from CHB to liver cirrhosis comes with significant changes in Th17/Treg ratio, which is correlated with a decrease in liver function, and also closely associated with the development and progression of inflammation.

Chemical Composition and Biological Activities of Essential Oils of Curcuma Species

Members of the genus Curcuma L. have been used in traditional medicine for centuries for treating gastrointestinal disorders, pain, inflammatory conditions, wounds, and for cancer prevention and antiaging, among others. Many of the biological activities of Curcuma species can be attributed to nonvolatile curcuminoids, but these plants also produce volatile chemicals. Essential oils, in general, have shown numerous beneficial effects for health maintenance and treatment of diseases. Essential oils from Curcuma spp., particularly C. longa, have demonstrated various health-related biological activities and several essential oil companies have recently marketed Curcuma oils. This review summarizes the volatile components of various Curcuma species, the biological activities of Curcuma essential oils, and potential safety concerns of Curcuma essential oils and their components.

A Component Formula of Chinese Medicine for Hypercholesterolemia Based on Virtual Screening and Biology Network

Hypercholesterolemia is a risk factor to atherosclerosis and coronary heart disease II. The abnormal rise of cholesterol in plasma is the main symptom. Cholesterol synthesis pathway is an important pathway of the origin of cholesterol, which is an essential pathway for the therapy of hypercholesterolemia. The 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), squalene synthase (SQS), and sterol regulatory element binding protein-2 (SREBP-2) are closely connected with the synthesis of cholesterol. The inhibition of these targets can reduce the cholesterol in plasma. This study aimed to build a component formula including three Traditional Chinese Medicines (TCM) components with the inhibition activity of these targets by using virtual screening and biological network. Structure-based pharmacophore models of HMG-CoA reductase and SQS and ligand-based pharmacophore model of SREBP-2 were constructed to screen the Traditional Chinese Medicine Database (TCMD). Molecular docking was used for further screening of components of HMG-CoA reductase and SQS. Then, metabolic network was constructed to elucidate the comprehensive interaction of three targets for lipid metabolism. Finally, three potential active compounds were obtained, which are poncimarin, hexahydrocurcumin, and forsythoside C. The source plants of the compounds were also taken into account, which should have known action of lowering hyperlipidemia. The lipid-lowering effect of hexahydrocurcumin was verified by experiment in vitro. The components that originated from TCMs with lipid-lowering efficacy made up a formula with a synergistic effect through the computer aid drug design methods. The research provides a fast and efficient method to build TCM component formula and it may inspire the study of the explanation of TCM formula mechanism.

Protection by the Total Flavonoids from Rosa laevigata Michx Fruit against Lipopolysaccharide-Induced Liver Injury in Mice via Modulation of FXR Signaling

We previously reported the effects of the total flavonoids (TFs) from Rosa laevigata Michx fruit against carbon tetrachloride-induced liver damage, non-alcoholic fatty liver disease, and liver ischemia-reperfusion injury. However, there have been no papers reporting the role of R. laevigata TFs against lipopolysaccharide (LPS)-induced liver injury. In this paper, liver injury in mice was induced by LPS, and R. Laevigata extract was intragastrically administered to the mice for 7 days. Biochemical parameters in serum and liver tissue were examined, and pathological changes were observed by transmission electron microscopy, hematoxylin and eosin (H&E) and Oil Red O staining. The results showed that the TFs markedly reduced serum ALT (alanine transferase), AST (aspartate transaminase), TG (total triglyceride), and TC (total cholesterol) levels and relative liver weights and improved liver pathological changes. In addition, the TFs markedly decreased tissue MDA (malondialdehyde) level and increased the levels of SOD (superoxide dismutase) and GSH-Px (glutathione peroxidase). A mechanistic study showed that the TFs significantly increased the expression levels of Nrf2 (nuclear erythroid factor2-related factor 2), HO-1 (heme oxygenase-1), NQO1 (NAD(P)H dehydrogenase (quinone 1), GCLC (glutamate-cysteine ligase catalytic subunit), and GCLM (glutamate-cysteine ligase regulatory subunit) and decreased Keap1 (Kelch-like ECH-associated protein 1) level by activating FXR (farnesoid X receptor) against oxidative stress. Furthermore, the TFs markedly suppressed the nuclear translocation of NF-&kappa;B (nuclear factor-kappa B) and subsequently decreased the expression levels of IL (interleukin)-1&beta;, IL-6, HMGB-1 (high -mobility group box 1), and COX-2 (cyclooxygenase-2) by activating FXR and FOXO3a (forkhead box O3) against inflammation. Besides, the TFs obviously reduced the expression levels of SREBP-1c (sterol regulatory element-binding proteins-1c), ACC1 (acetyl-CoA carboxylase-1), FASN (fatty acid synthase), and SCD1 (stearoyl-coenzyme A desaturase 1), and improved CPT1 (carnitine palmitoyltransferase 1) level by activating FXR to regulate lipid metabolism. Our results suggest that TFs exhibited protective effect against LPS-induced liver injury by altering FXR-mediated oxidative stress, inflammation, and lipid metabolism, and should be developed as an effective food and healthcare product for the therapy of liver injury in the future.

Protective Effects of Dioscin against Lipopolysaccharide-Induced Acute Lung Injury through Inhibition of Oxidative Stress and Inflammation

The protective effects of dioscin, a natural steroidal saponin from some medicinal plants including Dioscorea nipponica Makino, against lipopolysaccharide (LPS)- induced acute liver and renal damages have been reported in our previous works. However, the actions of dioscin against LPS-induced acute lung injury (ALI) is still unknown. In the present study, we investigated the effects and mechanisms of dioscin against LPS-induced ALI in vitro and in vivo. The results showed that dioscin obviously inhibited cell proliferation and markedly decreased reactive oxidative species level in 16HBE cells treated by LPS. In addition, dioscin significantly protected LPS-induced histological changes, inhibited the infiltration of inflammatory cells, as well as decreased the levels of MDA, SOD, NO and iNOS in mice and rats (p < 0.05). Mechanistically, dioscin significantly decreased the protein levels of TLR4, MyD88, TRAF6, TKB1, TRAF3, phosphorylation levels of PI3K, Akt, IκBα, NF-κB, and the mRNA levels of IL-1β, IL-6, and TNF-α against oxidative stress and inflammation (p < 0.05). Dioscin significantly reduced the overexpression of TLR4, and obviously down-regulated the levels of MyD88, TRAF6, TKB1, TRAF3, p-PI3K, p-Akt, p-IκBα, and p-NF-κB. These findings provide new perspectives for the study of ALI. Dioscin has protective effects on LPS-induced ALI via adjusting TLR4/MyD88- mediated oxidative stress and inflammation, which should be a potent drug in the treatment of ALI.

Coagulin-L ameliorates TLR4 induced oxidative damage and immune response by regulating mitochondria and NOX-derived ROS

Withanolides possess diverse biological and pharmacological activity but their immunomodulatory function is less realized. Hence, coagulin-L, a withanolide isolated from Withania coagulans Dunal has been studied for such an effect in human and murine cells, and mice model. Coagulin-L (1, 3, 10μM) exhibited immunomodulatory effect by suppressing TLR4 induced immune mediators such as cytokines (GMCSF, IFNα, IFNγ, IL-1α, IL-1Rα, IL-1β, IL-2, IL-2R, IL-4, IL-5, IL-6, IL-7, IL-10, IL-12 (p40/p70), IL-13, IL-15, IL-17), chemokines (IL-8/CXCL8, MIG/CXCL9, IP-10/CXCL10, KC, MCP-1/CCL2, MIP-1α/CCL3, MIP-1β/CCL4, RANTES/CCL5, eotaxin/CCL11), growth factors (FGF-basic, VEGF), nitric oxide and intracellular superoxide. Mechanistically, coagulin-L abrogated LPS induced total and mitochondrial ROS generation, NOX2, NOX4 mRNA expression, IRAK and MAPK (p38, JNK, ERK) activation. Coagulin-L also attenuated IκBα degradation, which prevented NFκB downstream iNOS expression and pro-inflammatory cytokine release. Furthermore, coagulin-L (10, 25, 50mg/kg, p.o.), undermined the LPS (10mg/kg, i.p.) induced endotoxemia response in mice as evinced from diminished cytokine release, nitric oxide, aortic p38 MAPK activation and endothelial tissue impairment besides suppressing NOX2 and NOX4 expression in liver and aorta. Moreover, coagulin-L also alleviated the ROS mediated oxidative damage which was assessed through protein carbonyl, lipid hydroperoxide, 8-isoprostane and 8-hydroxy-2-deoxyguanosine quantification. To extend, coagulin-L also suppressed carrageenan-induced paw edema and thioglycollate-induced peritonitis in mice. Therefore, coagulin-L can be of therapeutic importance in pathological conditions induced by oxidative damage.

A Standardized Chemically Modified Curcuma longa Extract Modulates IRAK-MAPK Signaling in Inflammation and Potentiates Cytotoxicity

The TLR/IL-1R pathway is a critical signaling module that is misregulated in pathologies like inflammation and cancer. Extracts from turmeric (Curcuma longa L.) enriched in curcumin and carbonyls like turmerones have been shown to exert potent anti-inflammatory effects. The present study evaluated the anti-inflammatory activity, cytotoxic effect and the underlying mechanism of a novel chemically modified, non-carbonyl compound enriched Curcuma longa L. (C. longa) extract (CMCE). CMCE (1 or 10 μg/mL; 14 h) significantly decreased LPS (50-100 ng/mL) induced TNF-α and IL-1β production in THP-1 cells, human, and mouse whole blood as measured by ELISA. LPS-induced IRAK1, MAPK activation, TLR4 expression, TLR4-MyD88 interaction, and IκBα degradation were significantly reduced in CMCE pre-treated THP-1 cells as assessed by Western blotting. CMCE (30, 100, and 300 mg/kg; 10 days p.o.) pre-treated and LPS (10 mg/kg) challenged Swiss mice exhibited attenuated plasma TNF-α, IL-1β, nitrite, aortic iNOS expression, and vascular dysfunction. In a PI permeability assay, cell lines derived from acute myeloid leukemia were most sensitive to the cytotoxic effects of CMCE. Analysis of Sub-G1 phase, Annexin V-PI positivity, loss of mitochondrial membrane potential, increased caspase-3, and PARP-1 activation confirmed CMCE induced apoptosis in HL-60 cells. IRAK inhibition also sensitized HL-60 cells to CMCE induced cytotoxicity. The present study defines the mechanism underlying the action of CMCE and suggests a therapeutic potential for its use in sepsis and leukemia.