Immunostimulatory Activity of Polysaccharides Extracted from Celosia cristata Flowers.

Macrophages play a major role in innate immune responses by producing a variety of immune mediators and cytokines. The stimulation of macrophages by natural products may lead to an enhanced innate immune system. This study evaluated the immunostimulatory effects of a polysaccharide-rich crude fraction of Celosia cristata L. flowers (CCP) on murine macrophages. CCP treatment induced the production of inducible nitric oxide synthase, cyclooxygenase-2, and cytokines by macrophages. Mechanistically, the activation of mitogen-activated protein kinases, NF-κB and toll-like receptor 4 were found to be associated with the stimulatory functions of CCP. CCP was found to be primarily composed of galacturonic acid and glucose in addition to small amounts of arabinose and galactose. This study demonstrated that CCP may enhance the innate immune responses and potentially improve the immune functions in the body.

Chemical compounds with a neuroprotective effect from the seeds of Celosia argentea L.

Oxidative stress plays a central role in the common pathophysiology of neurodegenerative diseases such as Alzheimer's disease, amyotrophic lateral sclerosis, and Parkinson's disease. Antioxidant therapy has been suggested for the prevention and treatment of neurodegenerative diseases. Compounds derived from natural sources may offer the potential for new treatment options. Semen Celosiae is a traditional Chinese edible herbal medicine with a long history in China and exhibits wide-reaching biological activities such as hepatoprotective, anti-tumor, anti-diarrheal, anti-diabetic, anti-oxidant, etc. In this study, nine saponins and two phenylacetonitrile glycosides were isolated from Semen Celosiae and their structures were identified using ESI-MS and NMR techniques. Among them, compounds 1 and 2 have not been previously reported. The total concentrations of the five triterpenoid saponins and the two phenylacetonitrile glycosides were 3.348 mg g-1 and 0.187 mg g-1, respectively, suggesting that Semen Celosiae is a novel viable source of the two kinds of compounds. These compounds were observed to significantly attenuate t-BHP-induced neuronal damage by effectively enhancing cell viability and decreasing reactive oxygen species generation and cell apoptosis rate in NSC-34 cells. Furthermore, compounds 1 and 7 reduced the ratios of cleaved caspase-3: caspase-3 and cleaved caspase-7: caspase-7 and the level of cytochrome C, while they increased the levels of SOD1 and Beclin 1. These findings suggest that compounds 1-11 are potent inhibitors of neuron injury elicited by t-BHP, possibly via inhibition of oxidative stress and apoptosis, and activation of autophagy; therefore they may be valuable leads for future therapeutic development.

Anti-inflammatory and cytotoxic evaluation of extracts from the flowering stage of Celosia argentea.

BACKGROUND: This study was aimed at investigating the possible anti-inflammatory and cytotoxic effects of extracts from the flowering stage of C. argentea. This growth stage was chosen because of its high polyphenolic content and high antioxidant capacity. METHODS: Anti-inflammatory potential of the aqueous, acetone and methanol extracts of C. argentea was evaluated through the inhibition of nitric oxide production (LPS-induced) on stimulated macrophages (RAW 264.7), while MTT assay was used to assess cell viability with Silymarin as standard. Cytotoxicity of the plant extracts was evaluated on murine preadipocyte cell line (3 T3-L1) using the image-based method of two DNA-binding dyes; Hoechst 33342 and propidium iodide (PI) with melphalan as standard. RESULTS: Acetone extract exhibited moderate, dose-dependent anti-inflammatory activity with no significant toxicity to activated macrophages, however the aqueous and methanol extracts were unable to inhibit nitric oxide production at both trials. MTT assay and the toxicity assay revealed that the flowering stage extracts of C. argentea were not toxic to the RAW 264.7 macrophages and 3 T3-L1 cells at all the tested concentrations (0, 2, 50, 100 and 200 µg/mL). CONCLUSIONS: These findings corroborate the traditional use of C. argentea for painful inflammatory conditions and encourage its possible use as lead for the development of novel, non-toxic, anti-inflammatory agents.

Anti-neuroinflammatory effect of Iresine celosia on lipopolysaccharide-stimulated microglial cells and mouse.

Abnormal inflammatory response in the central nervous system plays a critical role in various neurological disorders such as Parkinson's disease, Alzheimer's disease and Huntington's disease. Therefore, modulation of abnormal neuroinflammation is thought to be a promising therapeutic strategy for these diseases. Based on this idea, we focused on finding a potential candidate material that would regulate excessive neuroinflammation. Iresine celosia has long been used as a traditional Mexican medicine to treat fever and oral disorders. In the present study, we evaluated the anti-neuroinflammatory effects of Iresine celosia extract (ICE) in lipopolysaccharide (LPS)-stimulated BV2 microglia cells and mice models. In BV2 microglia cells, ICE markedly inhibited production of nitric oxide and proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1ß, and interleukin-6 without causing cytotoxicity. ICE also ameliorated translocation of nuclear factor-κB from cytosol to nucleus by LPS. Moreover, ICE attenuated behavioral disturbances by inhibiting activation of microglia and astrocytes in LPS-treated mice. Collectively, these data indicate that ICE is a potential therapeutic agent for treating inflammation-related diseases.

A pair of cyclopeptide epimers from the seeds of Celosia argentea.

Two cyclopeptides, celogentin L (1) and its epimer lyciumin A (2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1D-, 2D-NMR, and HR-ESI/MS. The absolute configurations of amino acid components were assigned via chiral-phase HPLC analyses after acid hydrolysis. Furthermore, the configuration of C-N linkage at the glycine Cα was elucidated by extensive analyses of 2D-NMR and comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Cytotoxicity of the two compounds against human alveolar epithelial A549, hepatocellular carcinoma HepG2, and cervical cancer Hela cell lines was assayed. Although both of them were inactive in these cells, the present findings add new facets for the chemistry of Celosia argentea.

Celosins inhibit atherosclerosis in ApoE-/- mice and promote autophagy flow.

ETHNOPHARMACOLOGICAL RELEVANCE: Semen celosiae is a traditional Chinese medicine for purging hepatic pathogenic fire and removing nebula to improve eyesight, treating hepatopyretic vertigo and hypertension. It possesses a serial of potential bioactivities such as hepatoprotection, anti-tumor and anti-inflammatory, anti-diabetes. The triterpenoid saponins celosins from it were proved to have hepatoprotection, lipid lowing and anti-inflammatory. However, the anti-atherosclerosis activities were not reported to date. AIM OF THE STUDY: This study was designed to examine the therapeutic effects of celosins (CES), the active constituents extracted from Semen celosiae. MATERIALS AND METHODS: Atherosclerosis model by feeding high fat diet for 12 weeks in ApoE-/- mice and foam cell model by ox-LDL-treated peritoneal macrophages were performed. The lipid plaque was measured by histopathological analysis. The LC3 dots in the aortic root lesion examined through tissue immunofluorescence. The peritoneal macrophage phagocytosis, formation of foam cells, genes associated protein expression and autophagy flux were measured on foam cell model by oxidized low-density lipoprotein (Ox-LDL) stimulating peritoneal macrophages. The mRNA expression of CD36, SR-A1, ABCA1 and ABCG1 were determined by Real-Time PCR method. The expressions of LC3 and beclin 1 were measured using Western blot. RESULTS: CES (10, 30, 90mg/kg; p.o.) administrated for 4 weeks significantly reduced the prevalence of the relative area of plaque in mouse aorta, and showed the therapeutic effect on atherosclerosis. In the tissue section of immunofluorescence for aortic root, compared with high fat diet model group, the number of autophagy bodies in CES group increased significantly, suggesting that inhibiting atherosclerosis effect of CES may be related to its promoting autophagy. In vitro, CES significantly reduced phagocytosis of macrophages on lipid and formation rate of foam cells. CES down-regulated the mRNA expression of CD36 and SR-A1 while up-regulated mRNA expression of ABCA1 and ABCG1. Further, CES increased the autophagy specific protein LC3 and beclin 1, and it also increased the level of autophagy in the cells, and promoted the process of autophagy. CONCLUSIONS: The therapeutic effect of CES on atherosclerosis may be related to the promotion of autophagy.

Cytotoxic coumaronochromones from the inflorescences of Celosia cristata.

Investigation on the MeOH extracts of the inflorescences of Celosia cristata led to the isolation of two new coumaronochromones, cristatone I (1) and cristatone II (2), along with three known flavones (3-5). Their structures were elucidated on the basis of spectroscopic analyses. Compounds 1-5 were tested for their cytotoxic activity against HeLa and BGC-823 cancer cell lines, of which cristatone II (2) showed interesting activity with the IC50 value of 23.82 µM.

Dereplication-guided isolation of novel hepatoprotective triterpenoid saponins from Celosiae Semen by high-performance liquid chromatography coupled with electrospray ionization tandem quadrupole-time-of-flight mass spectrometry.

Although natural products (NPs) from ethnomedical plants have played a vital role in modern drug discovery, separation and purification of bioactive compounds from plant extract is still challenging. In this study, a dereplication strategy using HPLC-QTOF-MS was employed to rapidly discover and highly targeted isolate the novel hepatoprotective triterpenoid saponins from the methanol extract of Celosiae Semen. Firstly, four known saponins, i.e. celosin H, celosin I, celosin J, and pseudoginsenoside RT1 were selected as model compounds, and their fragmentation patterns in ESI-QTOF-MS/MS were characterized. Secondly, an HPLC-QTOF-MS/MS method was applied to chemically screen the saponins of interest, and thereby to guide the subsequent fraction and isolation procedure. Thirdly, the targeted isolation of desired compounds afforded two new triterpenoid saponins namely celosin K (1) and celosin L (2), which were structurally elucidated by combination of extensive NMR spectroscopic and chemical analyses. Finally, the protective effects of compounds 1 and 2 against APAP-induced hepatotoxicity in HepG2 cells were evaluated. These results indicate that the HPLC-QTOF-MS-guided isolation is an efficient methodology for isolating new NPs from medicinal plants through improving selectivity in separation and purification process.

Purification, characterization and immunomodulatory activity of a polysaccharide from Celosia cristata.

A polysaccharide CP1-1 was isolated and purified from Celosia cristata. Its average molecular weight was 2.3kDa and it was composed of glucose and galactose in a ratio of 1.00:2.03, and traces of mannose. Chemical characterization of CP1-1 was elucidated by methylation analysis. CP1-1 was a branched glucogalactan which was mainly composed of 1,6-linked Galp and 1,6-linked Glcp with a ratio of 5.6:3.8. The branches were at the O-3 of the main chain and might be composed of single terminal (1→)-linked glucopyranose and galactopyranose. CP1-1 also significantly promoted the proliferation and neutral red phagocytosis of RAW 264.7 macrophage cells in vitro. In addition, CP1-1 promoted cell proliferation by enhancing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1ß. These results suggested that the polysaccharide from C. cristata could be used as a potential immunostimulator.

Production of dihydroxylated betalains and dopamine in cell suspension cultures of Celosia argentea var. plumosa.

Betalains are plant pigments of hydrophilic nature with demonstrated chemopreventive potential in cancer cell lines and animal models. Among the betalains, those containing an aromatic moiety with two free hydroxyl groups possess the strongest antioxidant and free radical scavenging activities. The betaxanthins dopaxanthin and miraxanthin V and the betacyanins betanidin and decarboxy-betanidin are the only natural betalains with catecholic substructures. These four pigments have been produced in cell cultures established from hypocotyls of the plant Celosia argentea. Two stable and differentially colored cell lines, yellow and red, were maintained on Murashige and Skoog medium supplemented with the plant growth regulators 6-benzylaminopurine (6.66 µM) and 2,4-dichlorophenoxyacetic acid (6.79 µM). Derived suspension cultures showed increased production of dihydroxylated betalains in the cells and secreted to the medium with a maximum reached after 8 days of culture. In addition, precursor molecules betalamic acid and dopamine, with content up to 42.08 mg/g dry weight, were also obtained. The joint presence of the bioactive betalains together with the production of dopamine and betalamic acid show the ability of cell cultures of C. argentea to become a stable source of valuable phytochemicals.

Antioxidant activity and protective effect of extract of Celosia cristata L. flower on tert-butyl hydroperoxide-induced oxidative hepatotoxicity.

This study was undertaken to evaluate the antioxidant potential and protective effects of Celosia cristata L. (Family: Amaranthaceae) flower (CCF) extracts on tert-butyl-hydroperoxide (t-BHP)-induced oxidative damage in the hepatocytes of Chang cells and rat livers. In vitro, CCF extracts exhibited protective effect through their radical scavenging ability to enhance cell viability, prevent reactive oxygen species (ROS) generation, and inhibit mitochondrial membrane depolarisation in t-BHP-induced hepatotoxicity in Chang cells. In vivo, oral feeding of CCF (100mg and 500mg/kg of body weight) to rats for five consecutive days before a single dose of t-BHP (2mmol/kg, i.p.) showed a significant (p<0.05) protective effect by lowering serum levels of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT). The extract decreased the hepatic levels of lipid peroxidation (MDA) and serum level of triglyceride (TG) against t-BHP-induced oxidative stress. These results indicate that CCF extract prevented oxidative stress-induced liver injury by enhancing hepatocyte antioxidant abilities.

Differential fusion expression and purification of a cystatin in two different bacterial strains.

To date, the identification of the novel multifunctional properties of cysteine proteinase inhibitors "known as cystatins" is the great of interests for molecular biologists. The efficient production, purification and correctly folded form of these proteins are the most important requirements for their any basic research. To the best of our knowledge, maltose-binding protein (MBP) fusion tags are being used to overcome the impediment to their heterologous recombinant expression in Escherichia coli as insoluble and bio-inactive inclusion bodies. In the present work, to evaluate the expression efficiency of a cystatin molecule in E. coli cells by using MBP tags, the expression of Celosia cystatin was studied in two different strains of this bacterium. The quantitative analysis results based on the one-step purification yield of the fused product showed the excellency of the E. coli TB1 strain in comparison to E. coli DH5alpha for the high-level production of active product.

Triterpenoid saponins from the seeds of Celosia argentea and their anti-inflammatory and antitumor activities.

Three new triterpenoid saponins, named celosin E (1), celosin F (2) and celosin G (3), together with a known compound cristatain (4), were isolated from the seeds of Celosia argentea L. (Amaranthaceae). All the isolated compounds were obtained for the first time from this plant. The structures of new compounds were characterized on the basis of extensive NMR experiments and mass spectrometry data. The antitumor and anti-inflammatory activities of the four compounds were tested in vitro.

A new phenolic glycoside and cytotoxic constituents from Celosia argentea.

A new phenolic glycoside, 4-O-ß-D-apifuranosyl-(1→2)-ß-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (2) and 11 known compounds were isolated from the MeOH extract of the plant Celosia argentea. The structures of the compounds were elucidated on the basis of spectroscopic analysis and chemical methods. Among the isolated compounds, stigmasterol (10) showed moderate inhibitory activities against SGC-7901 and BEL-7404 cells.

Storage behavior of immune-enhancing enteral formulation from natural sources.

Nutrition support has become an important therapeutic intervention for improving outcomes in hospitalized patients. The present study was carried out with the objective of studying appropriate packaging and storage studies of enteral formulation from natural sources comprising finger millet (Eleusine coracana), soyprotein isolate, tomato powder, carrot powder, anne greens (Celosia argentea), groundnut oil and fish oil. Two type of packages--namely, polypropylene pouches and metallized polyester/polyethylene pouches--were used. The storage conditions were 27°C and 42°C at 65% relative humidity. The chemical, microbiological and sensory qualities of the formulation were assessed at regular intervals. The moisture sorption studies revealed that the formulation had an initial moisture content of 3.59%, which equilibrated to 13%. The product was acceptable at 64% relative humidity, after which it tend to become soggy. Analysis of peroxide value and free fatty acid content of the equilibrated samples revealed that moisture content of 4-5% was ideal for the storage of the formulation. An increase in the peroxide value and free fatty acid content was observed during 90-day storage period but the formulation was organoleptically acceptable. The microbial analysis of the formulation revealed an initial total bacterial count of 1.5 × 10² colony-forming units and increased to 7.9 × 10² colony-forming units (polypropylene) and 5.0 × 10² colony-forming units (metallized polyester/polyethylene). No fungal and coliform was detected at 90 days of storage. Thus it was concluded that the formulation can be stored for a period of 3 months at 27°C and 65% relative humidity. Such formulations can be primarily a supportive strategy to an active therapeutic intervention.

Molecular cloning and functional identification of a ribosome inactivating/antiviral protein from leaves of post-flowering stage of Celosia cristata and its expression in E. coli.

A full-length cDNA clone, encoding a ribosome inactivating/antiviral protein (RIP/AVP) was isolated from the cDNA library of post-flowering stage of Celosia cristata leaves. The full-length cDNA consisted of 1015 nucleotides, with an open reading frame encoding 283 amino acids. The deduced amino acid sequence had a putative active site domain conserved in other ribosome inactivating/antiviral proteins (RIPs/AVPs). The coding region of the cDNA was amplified by polymerase chain reaction (PCR), cloned and expressed in Escherichia coli as recombinant protein of 72 kDa. The expressed fusion product was confirmed by Western analysis and purification by affinity chromatography. Both the recombinant protein (reCCP-27) and purified expressed protein (eCCP-27) inhibited translation in rabbit reticulocytes showing IC50 values at 95 ng and 45 ng, respectively. The native purified nCCP-27 has IC50 at 25 ng. The purified product also showed N-glycosidase activity towards tobacco ribosomes and antiviral activity towards tobacco mosaic virus (TMV) and sunnhemp rosette virus (SRV).

Pro- and antioxidant effects and cytoprotective potentials of nine edible vegetables in southwest Nigeria.

Antioxidant and cytoprotective activities of boiled, cold, and methanolic extracts of nine edible vegetables in Southwest Nigeria were evaluated in the 1,1-diphenyl-2-picrylhydrazyl free radical assay and hemagglutination assay in bovine erythrocytes, respectively. Crassocephalum rubens showed the highest antioxidant activity (56.5%), Solanum americanum and Vernonia amygdalina exhibited moderate antioxidant activity (26.0-37.5% and 14.8-36.2%, respectively), Solanum macrocarpon, Telfaria occidentalis, Amaranthus hybridus, and Jatropha tanjorensis produced weak activity (1.6-15.8%, 1.6-7.7%, 2.8-6.62%, and 10.7-12.1%, respectively), while Celosia argentea and Talinum triangulare were pro-oxidants. It was also shown that extracts from all the vegetables are pro-oxidants at high concentrations of either 1 or 5 mg/mL or both. On the other hand, the studies on the cytoprotective effect showed that all the plant extracts demonstrated a very low hemagglutination titer value between 0.32 and 5.56 except S. americanum methanolic extract, which had a titer of 50.0. These results indicated correlation between the antioxidant properties and the hemagglutination values of these plant extracts; however, the membrane stabilizing capacity of the extracts supports the plants' antioxidant activity.

Cystatins may confer viral resistance in plants by inhibition of a virus-induced cell death phenomenon in which cysteine proteinases are active: cloning and molecular characterization of a cDNA encoding cysteine-proteinase inhibitor (celostatin) from Celosia cristata (crested cock's comb).

Cystatins (cysteine proteinase inhibitors) have been recently used in plants as antiviral strategy against those viruses whose replication involves cysteine proteinase activity. We proposed an idea that cystatins may confer resistance by inhibition of a virus-induced cell-death phenomenon in which cysteine proteinases are active. To test this idea, a full-length cDNA library was constructed from the preflowering stage of Celosia cristata (crested cock's comb) leaves, and a cDNA clone with cystatin domain was isolated using an oligonucleotide probe designed on the basis of the conserved peptide of plant cystatins. It was expressed in an Escherichia coli expression system as a fusion protein. The purified recombinant product, termed 'celostatin' (Celosia cystatin), inhibited the enzymatic activity of papain indicating its cystatin activity and prevented TMV (tobacco mosaic virus)-induced hypersensitive-response cell death in Nicotiana glutinosa (a wild species of tobacco) leaves by 65-70% at the concentration of approx. 50 ng/ml. It also offered resistance against TMV and caused normal growth of the test plant. Since the activity of cysteine proteinases is not involved in the TMV replication process, we speculated that inhibition of the hypersensitive response by celostatin may be due to the inactivation of proteolysis involved in the plant cell death programme, a phenomenon that has already been reported in animal systems.