Efecto antiinflamatorio y antioxidante in vitro de Curcuma longa sobre macrófagos murinos durante la infección por Helicobacter pylori

RESUMEN Introducción: La colonización por Helicobacter pylori produce una inflamación en la mucosa gástrica con el consecuente desarrollo de enfermedades gastroduodenales. Frente a altas tasas de resistencia antimicrobiana y la ausencia de una vacuna en humanos, la alternativa ha sido la búsqueda de extractos de plantas con propiedades antimicrobiana, antiinflamatoria, antioxidante, antifúngica y anticancerígena como la Curcuma longa. Sin embargo, al ser una especie introducida y adaptada a las condiciones climáticas del país, son necesarios los estudios preclínicos que avalen su potencial antiinflamatorio y antioxidante. Objetivo: Evaluar el efecto del extracto de C. longa sobre macrófagos peritoneales infectados con H. pylori. Métodos: Para evaluar el efecto antiinflamatorio y antioxidante del extracto de C. longa sobre macrófagos murinos infectados por H. pylori, se evaluaron diferentes concentraciones del extracto y relaciones de bacteria, y se evaluó la muerte celular mediante DAPI. Se determinó la producción de óxido nítrico, peróxido de hidrógeno y los niveles de la interleucina-1β. Resultados: La viabilidad del macrófago se afectó frente a concentraciones de 100 µg/mL del extracto de cúrcuma y a partir de 25 bacterias/macrófago. Al combinar las diferentes concentraciones del extracto con las multiplicidades bacterianas se observó una reducción en los niveles de H2O2 e IL-1β; sin embargo, la reducción del óxido nítrico se observó en el rango de 6,25-50 µg/mL del producto natural. Conclusiones: El extracto de cúrcuma cubano mostró potencial antioxidante y antiinflamatorio al disminuir la citotoxicidad celular y la producción de especies reactivas del oxígeno en macrófagos peritoneales.

ABSTRACT Introduction: Colonization by Helicobacter pylori causes inflammation of the gastric mucosa with the consequent development of gastroduodenal diseases. In view of the high antimicrobial resistance rates and the absence of a vaccine for humans, the alternative has been to search for plant extracts with antimicrobial, anti-inflammatory, antioxidant, antifungal and anticancer properties. An example is Curcuma longa. However, being as it is a species introduced and adapted to the country's climate conditions, it is necessary to conduct preclinical studies demonstrating its anti-inflammatory and antioxidant potential. Objective: Evaluate the effect of a C. longa extract on peritoneal macrophages infected by H. pylori. Methods: With the purpose of describing the anti-inflammatory and antioxidant effect of C. longa on murine macrophages infected by H. pylori, an evaluation was conducted of various extract concentrations and bacterial relationships, while cell death was assessed by DAPI. Determination was made of nitric oxide and hydrogen peroxide production, as well as of interleukin-1β levels. Results: Viability of the macrophage was affected in the presence of 100 µg/ml concentrations of the turmeric extract and as from 25 bacteria / macrophage. When different concentrations of the extract were combined with the bacterial multiplicities, a reduction was observed in H2O2 and IL-1β levels. However, nitric oxide reduction was observed within the range of 6.25-50 µg/ml of the natural product. Conclusions: The Cuban turmeric extract was found to have antioxidant and anti-inflammatory potential by reducing cell cytotoxicity and the production of reactive oxygen species in peritoneal macrophages.

Cordycepin negatively modulates LPS-induced cytokine production by induction of Heme Oxygenase-1 / 实用医学杂志

Objective To investigate the mocelualr mechanism of Cordycepin negative modulates LPSinduced cytokine production in murine macrophages.Methods The RAW264.7 murine macrophages were cultured in vitro and were pre-treated by different concentration of Cordycepin,and then stimulated by LPS for 8 h.Production of TNF-o,IL-6 and IL-12,and the content of p65 in the nuclear were detected by ELISA.Expression of heme oxygenase-1 (HO-1) and phosphorylation of IκB and p38 were measured by Western blot.Nuclear translocation of Nrf2 was detected by Immunofluorescence.Results 1 ～ 30 μg/mL of Cordycepin treatment significantly abrogated LPS-induced TNF-α,IL-6 and IL-12 production,p65 nuclear translocation and IκB phosphorylation.In addition,different concentration of Cordycepin could also induce RAW264.7 cells expression of HO-1,phosphorylation of p38 and nuclear translocation of Nrf2.Application of p38 inhibitor and small interfering RNA-mediated knock-down of Nrf-2 significantly inhibited surfactin-induced HO-1 expression.Treatment with a selective inhibitor of HO-1 reversed the Cordycepin mediated inhibition of pro-inflammatory cytokines.Conclusions Cordycepin induces antiinflammatory effects by inhibition of NF-κB and activation of Nrf-2 and p38 mediated HO-1 induction.

Molecular mechanism of apigenin on inhibition of LPS-induced inflammatory mediators in murine macrophages / 中国免疫学杂志

Objective:To investigate the effect and the mechanism of Apigenin on lipopolysaccharides ( LPS )-induced inflammatory mediators production in murine macrophages. Methods:The murine macrophage cell line RAW 264. 7 cells were cultured in vitro,and were treated with different concentration of Apigenin followed by LPS administration. Expression of heme oxygenase-1 ( HO-1),cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS),phosphorylation of p38 and IκB,nuclear translocation of Nrf2 were detected by Western blot. Production of Nitrite and nitrate ( NOx) was analyzed by colorimetric technique. Secretion of prosta-glandin E2 (PGE2) was detected by ELISA. Activation of NF-κB was measured by luciferase assay. Results: Western blot indicated that apigenin could induce RAW 264. 7 cells expression of HO-1, and pretreatment of SB203580, an inhibitor of p38 significantly inhibited apigenin induced HO-1 expression. In addition,Apigenin could also decrease the content of nuclear transcription factor Nrf2 in cytoplasm and increase its level in the nucleus. Silencing of Nrf2 by specific siRNA could inhibit apigenin-induced HO-1 expression. Furthermore,apigenin administration significantly inhibited LPS-induced NOx production and PGE2 secretion, COX-2 and iNOS expression,IκB phosphorylation and NF-κB activation,and transfection of HO-1 siRNA could reverse these actions. Conclusion:Apigenin inhibits LPS-induced inflammatory response through induction of HO-1 and inhibition of NF-κB in macrophages.

Anti-Inflammatory and Anti-Superbacterial Properties of Sulforaphane from Shepherd's Purse

Shepherd's purse, Capsella bursa-pastoris (L.) Medik., has been considered a health food for centuries in Asia and is known to contain the isothiocyanate compound sulforaphane. In this study, we evaluated the anti-inflammatory and antibacterial properties of a sulforaphane-containing solution (SCS) isolated from shepherd's purse. SCS had significant anti-inflammatory activity indicated by the decreased levels of nitric oxide (NO), cytokines (interleukin 1beta [IL-1beta], IL-6, and IL-10), and prostaglandin E2 (PGE2) in lipopolysaccharide-stimulated RAW 264.7 murine macrophages. In addition, SCS decreased the inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2) levels, which confirmed the anti-inflammatory activity of SCS. Further, SCS inhibited vancomycin-resistant enterococci (VRE) and Bacillus anthracis. The minimal inhibitory concentration was 250 microg/ml for VRE and 1,000 microg/ml for B. anthracis. Taken together, these data indicate that SCS has potential anti-inflammatory and anti-superbacterial properties, and thus it can be used as a functional food or pharmaceutical.

Anti-Inflammatory and Anti-Superbacterial Activity of Polyphenols Isolated from Black Raspberry

The fruit of the black raspberry (Rubus coreanus Miquel) has been employed in traditional medicine, and recent studies have demonstrated its measureable biological activities. However, the root of the black raspberry has not been studied. Therefore, in this study, we evaluated the anti-inflammatory and antibacterial properties of the root and unripe fruit polyphenols of the black raspberry. Both polyphenols proved to have anti-inflammatory activity as evidenced by the decreased nitric oxide (NO), cytokines (IL-1beta , IL-6, and IL-10) and prostaglandin E2 (PGE2) levels in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages. However, root polyphenols showed stronger anti-inflammatory activity than fruit polyphenols. LPS-induced mRNA and protein expressions of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 levels were also decreased, confirming the anti-inflammatory activity. Root polyphenols showed lethal activity against methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Acinetobacter baumannii (CRAB), and Bacillus anthracis. In contrast, the black raspberry fruit did not demonstrate these properties. These data provide the first demonstration that black raspberry root has potential anti-inflammatory and anti-superbacterial properties that can be exploited as alternatives for use in the food and cosmetic industries and/or as pharmaceuticals.

Aging alters the production of iNOS, arginase and cytokines in murine macrophages

The limited amount of information on the primary age-related deficiencies in the innate immune system led us to study the production of inducible nitric oxide synthase (iNOS), arginase, and cytokines in macrophages of young (8 weeks old) and old (72 weeks old) female BALB/c mice. We first evaluated iNOS and arginase inducers on peritoneal (PMΦ) and bone marrow-derived (BMMΦ) macrophages of young BALB/c and C57BL/6 mice, and then investigated their effects on macrophages of old mice. Upon stimulation with lipopolysaccharide (LPS), resident and thioglycolate-elicited PMΦ from young mice presented higher iNOS activity than those from old mice (54.4 percent). However, LPS-stimulated BMMΦ from old mice showed the highest NO levels (50.1 percent). Identical NO levels were produced by PMΦ and BMMΦ of both young and old mice stimulated with interferon-γ. Arginase activity was higher in resident and elicited PMΦ of young mice stimulated with LPS (48.8 and 32.7 percent, respectively) and in resident PMΦ stimulated with interleukin (IL)-4 (64 percent). BMMΦ of old mice, however, showed higher arginase activity after treatment with IL-4 (46.5 percent). In response to LPS, PMΦ from old mice showed the highest levels of IL-1α (772.3 ± 51.9 pg/mL), whereas, those from young mice produced the highest amounts of tumor necrosis factor (TNF)-α (937.2 ± 132.1 pg/mL). Only TNF-α was expressed in LPS-treated BMMΦ, and cells from old mice showed the highest levels of this cytokine (994.1 ± 49.42 pg/mL). Overall, these results suggest that macrophages from young and old mice respond differently to inflammatory stimuli, depending on the source and maturity of the cell donors.

Effect of Hemidesmus indicus R.Br. root extract against Salmonella enterica serovar Typhimurium-induced apoptosis in murine macrophage cell line (P388D1).

Background & objectives: Previous studies on natural products had mainly dealt with their antimicrobial activity and studies on the interference of these bioactive compounds with host-bacterial interaction is limited. The present study was undertaken to investigate the effect of the sterols and fatty acids present in the chloroform fraction of crude methanol extract of Hemidesmus indicus root (CHI) on Salmonella enterica serovar Typhimurium (S. Typhimurium) mediated apoptosis in a murine macrophage cell line (P388D1). Methods: Bacterial sensitivity test was carried out with different concentrations of CHI and the optimum dose was fixed as 100 μg/ml for CHI, which was safe on host cells as the CD50 (50% of cell death) dose of CHI was determined to be 500 μg/ml in the P388D1 cell line. Results: The CHI-treated bacteria had negligible cytotoxicity and were less potent to invade and proliferate intracellularly. Murine macrophages infected with wild bacteria, stained with Hoechst 33258, had swollen and damaged morphology with characteristic apoptotic bodies whereas macrophages infected with treated bacteria had comparative normal architecture. Immunofluorescence and transmission electron micrographs both confirmed that CHI-treated bacteria were defective and smaller than the wild bacteria. Ultrastructures of P388D1 cells infected with wild bacteria showed many ingested bacteria and characteristic Salmonella-containing vacuoles (SCV). Some cells had condensed or fragmented nuclei with swollen mitochondria, whereas most of the cells infected with treated bacteria were normal in morphology and a few had internalized bacteria, but the typical bacteria laden SCV was not observed in cells infected with CHI-treated S. Typhimurium. Interpretation & conclusions: Our results showed that the choloroform fraction of H. indicus root blocked the cytotoxic activity of S. Typhimurium in a macrophage cell line. More studies need to be done to elaborate and confirm our findings.

Tetrachloroauric acide depresses the activation processes of phagocytic cells

Gold compounds depress phagocytic cell responses, including chemotaxis, and respiratory burst. However, the effects of gold compounds on the function of phagocytic cells are variable according to the preparation of medicine. In this study, effect of tetrachloroauric acid on activated neutrophil responses, including respiratory burst, lysosomal enzyme release and change of intracellular Ca2+ level and on the synthesis of interleukin-8 and granulocyte-macrophage colony stimulating factor by macrophages was studied. This study further examines how gold compounds affect the activation processes. The respiratory burst stimulated by complement C5a, degraded IgG and PMA in neutrophils was inhibited by tetrachloroauric acid. In contrast to C5a and degraded IgG, PMA-stimulated superoxide production was weakly inhibited by tetrachloroauric acid. Staurosporine, genistein, EGTA and verapamil inhibited superoxide and H2O2 production caused by C5a and degraded IgG. PMA-stimulated superoxide production was inhibited by staurosporine but was not affected by genistein. Tetrachloroauric acid, genistein, EGTA and verapamil inhibited the release of acid phosphatase and myeloperoxidase, while the effect of staurosporine was not detected. The synthesis of interleukin-8 and granulocyte-macrophage colony stimulating factor by interleukin-1beta in macrophages was inhibited by tetrachloroauric acid. Preincubation with tetrachloroauric acid, genistein, EGTA and verapamil, the elevation of (Ca2+)i evoked by C5a was inhibited. Store-regulated Ca2+ entry in thapsigargin-pretreated neutrophils was decreased by the addition of tetrachloroauric acid and genistein. The effect of staurosporine on intracellular Ca2+ mobilization was not observed. In conclusion, tetrachloroauric acid may suppress neutrophil responses through its inhibitory action on elevation of intracellular Ca2+ level and protein kinase C. It might exhibit an inhibitory effect on the action of protein tyrosine kinase. Tetrachloroauric acid depresses cytokine production by macrophages.