Bioactive C-phycocyanin exerts immunomodulatory and antitumor activity in mice with induced melanoma.

Melanoma is the most aggressive and deadly skin cancer. The difficulty in its treatment arises from its ability to suppress the immune system, making it crucial to find a substance that increases anti-tumor immunity. C-phycocyanin (C-PC) appears as a promising bioactive, with multifaceted effects against several cancers, but its efficacy against melanoma has only been tested in vitro. Therefore, we investigated C-PC's the anti-tumor and immunomodulatory action in a murine melanoma model. The tumor was subcutaneously induced in C57BL/6 mice by injecting B16F10 cells. The animals were injected subcutaneously with C-PC for three consecutive days. After euthanasia, the tumor was weighed and measured. The inguinal lymph node was removed, and the cells were stained with antibodies and analyzed by flow cytometry. The heart, brain and lung were analyzed by histopathology. C-PC increased the B cell population of the inguinal lymph node in percentage and absolute number. The absolute number of T lymphocytes and myeloid cells were also increased in the groups treated with C-PC. Thus, C-PC showed a positive immunomodulatory effect both animals with and without tumor. However, this effect was more pronounced in the presence of the tumor. Positive immune system modulation may be associated with a reduction in tumor growth in animals treated with C-PC. Administration of C-PC subcutaneously did not cause organ damage. Our findings demonstrate C-PC's immunomodulatory and anti-melanoma action, paving the way for clinical research with this bioactive.

Therapeutic potential of Phycocyanin in gastrointestinal cancers and related disorders.

Gastrointestinal cancer is the most fatal cancer worldwide. The etiology of gastrointestinal cancer has yet to be fully characterized. Alcohol consumption, obesity, tobacco, Helicobacter pylori and gastrointestinal disorders, including gastroesophageal reflux disease, gastric ulcer, colon polyps and non-alcoholic fatty liver disease are among the several risks factors for gastrointestinal cancers. Phycocyanin which is abundant in Spirulina. Phycocyanin, a member of phycobiliprotein family with intense blue color, is an anti-diabetic, neuroprotective, anti-oxidative, anti-inflammatory, and anticancer compound. Evidence exists supporting that phycocyanin has antitumor effects, exerting its pharmacological effects by targeting a variety of cellular and molecular processes, i.e., apoptosis, cell-cycle arrest, migration and Wnt/ß-catenin signaling. Phycocyanin has also been applied in treatment of several gastrointestinal disorders such as, gastric ulcer, ulcerative colitis and fatty liver that is known as a risk factor for progression to cancer. Herein, we summarize various cellular and molecular pathways that are affected by phycocyanin, its efficacy upon combined drug treatment, and the potential for nanotechnology in its gastrointestinal cancer therapy.

Unraveling the Anti-Aging Properties of Phycocyanin from the Cyanobacterium Spirulina (Arthrospira platensis).

In recent years, marine natural products have become one of the most important resources of novel lead compounds for critical diseases associated with age. Spirulina, a dietary supplement made from blue-green algae (cyanobacteria: scientific name Arthrospira platensis), is particularly rich in phycocyanin, a phycobiliprotein, which accounts for up to 20% of this cyanobacterium's dry weight and is considered responsible for its anti-cancer, anti-inflammatory and antioxidant activities. Although the anti-aging activity of phycocyanin has been investigated, how exactly this compound works against aging remains elusive. The aim of our research is to use the yeast Saccharomyces cerevisiae as a model organism to investigate the anti-aging properties of phycocyanin from A. platensis. Our results show that phycocyanin has a powerful anti-aging effect, greatly extending the chronological life span of yeast cells in a dose-dependent way, as the effect was also pronounced when cells were grown in SD medium under calorie restriction conditions (0.2% glucose). Both ROS and accumulation of dead cells were followed by staining chronologically aged cells with dihydrorhodamine 123 (DHR123) and propidium iodide (PI). Interestingly, we found that most of the aged phycocyanin-treated cells, which were unable to form colonies, were actually ROS+/PI-. Finally, we show that the moment in which phycocyanin is added to the culture does not substantially influence its effectiveness in counteracting chronological aging.

C-Phycocyanin Attenuates Noise-Induced Cochlear Synaptopathy via the Inhibition of Oxidative Stress and Intercellular Adhesion Molecule-1 in the Cochlea.

The synapses between inner hair cells (IHCs) and spiral ganglion neurons (SGNs) are the most vulnerable structures in the noise-exposed cochlea. Cochlear synaptopathy results from the disruption of these synapses following noise exposure and is considered the main cause of poor speech understanding in noisy environments, even when audiogram results are normal. Cochlear synaptopathy leads to the degeneration of SGNs if damaged IHC-SGN synapses are not promptly recovered. Oxidative stress plays a central role in the pathogenesis of cochlear synaptopathy. C-Phycocyanin (C-PC) has antioxidant and anti-inflammatory activities and is widely utilized in the food and drug industry. However, the effect of the C-PC on noise-induced cochlear damage is unknown. We first investigated the therapeutic effect of C-PC on noise-induced cochlear synaptopathy. In vitro experiments revealed that C-PC reduced the H2O2-induced generation of reactive oxygen species in HEI-OC1 auditory cells. H2O2-induced cytotoxicity in HEI-OC1 cells was reduced with C-PC treatment. After white noise exposure for 3 h at a sound pressure of 118 dB, the guinea pigs intratympanically administered 5 µg/mL C-PC exhibited greater wave I amplitudes in the auditory brainstem response, more IHC synaptic ribbons and more IHC-SGN synapses according to microscopic analysis than the saline-treated guinea pigs. Furthermore, the group treated with C-PC had less intense 4-hydroxynonenal and intercellular adhesion molecule-1 staining in the cochlea compared with the saline group. Our results suggest that C-PC improves cochlear synaptopathy by inhibiting noise-induced oxidative stress and the inflammatory response in the cochlea.

The Cyanobacterial "Nutraceutical" Phycocyanobilin Inhibits Cysteine Protease Legumain.

The blue biliprotein phycocyanin, produced by photo-autotrophic cyanobacteria including spirulina (Arthrospira) and marketed as a natural food supplement or "nutraceutical," is reported to have anti-inflammatory, antioxidant, immunomodulatory, and anticancer activity. These diverse biological activities have been specifically attributed to the phycocyanin chromophore, phycocyanobilin (PCB). However, the mechanism of action of PCB and the molecular targets responsible for the beneficial properties of PCB are not well understood. We have developed a procedure to rapidly cleave the PCB pigment from phycocyanin by ethanolysis and then characterized it as an electrophilic natural product that interacts covalently with thiol nucleophiles but lacks any appreciable cytotoxicity or antibacterial activity against common pathogens and gut microbes. We then designed alkyne-bearing PCB probes for use in chemical proteomics target deconvolution studies. Target identification and validation revealed the cysteine protease legumain (also known as asparaginyl endopeptidase, AEP) to be a target of PCB. Inhibition of this target may account for PCB's diverse reported biological activities.

Selenium enhances photodynamic therapy of C-phycocyanin against lung cancer via dual regulation of cytotoxicity and antioxidant activity.

As a natural photosensitizer, phycocyanin (PC) has high efficiency and uses low-intensity irradiation. To enhance the photodynamic therapy (PDT) of PC, we extract selenium-enriched phycocyanin (Se-PC) from Se-enriched Spirulina platensis and examine the synergistic effect of PC combined with selenium against lung tumors. In vitro experiments reveal that Se-PC PDT more efficiently reduce the survival rate of mouse lung cancer cells (LLC cell line) than PC PDT treatment by increasing the level of ROS and decreasing the level of GPx4, which is confirmed by the Chou-Talalay assay. In vivo imaging system analysis reveal that tumor volume is more markedly decreased in both the Se-PC PDT and PC PDT plus Na 2SeO 3 groups than in the PC PDT group, with inhibition rates reaching 90.4%, 68.3% and 53.1%, respectively, after irradiation with 100 J/cm 2 laser light at 630 nm. In normal tissues, Se-PC promotes the synthesis of antioxidant enzymes and the immune response by the IL-6/TNF-α pathway against tumor proliferation and metastasis. Using Se-PC as a photosensitizer in tumors, apoptosis and pyroptosis are the primary types of cell death switched by Caspases-1/3/9, which is confirmed by TEM. Based on the transcriptome analysis, Se-PC PDT treatment inhibits angiogenesis, regulates inflammation by the HIF-1, NF-κB and TGF-ß signaling pathways and dilutes tumor metabolism by reducing the synthesis of glucose transporters and transferrin. Compared to PC PDT, Se-PC increases the expression levels of some chemokines in the tumor niche, which recruits inflammatory cells to enhance the immune response. Our study may provide evidence for Se-PC as an effective photosensitizer to treat lung cancer.

Phycocyanin improved alcohol-induced hepatorenal toxicity and behavior impairment in Wistar rats.

The aim of this study was to investigate a potential preventive effect of phycocyanin extract from Spirulina platensis against ethanol- induced hepatorenal toxicity and cognitive behavior impairment in male Wistar rats. The animals were randomly and equally divided into four groups (six animals each): control group received saline solution, ethanol (EtOH) group was injected intraperitoneally with 1 ml/kg of ethanol solution 38% (w/v), phycocyanin groups were treated with 25 (PC1) or 50 (PC2) mg/kg phycocyanin extract followed by ethanol administration. All treatments were conducted for 14 successive days. Results revealed that ethanol induced oxidative stress in brain, liver, and kidney by increasing lipid peroxidation level and SOD and CAT activities. Serum biochemical perturbations were also observed in EtOH group, which was indicated by a significant elevation in ALT, AST, cholesterol, triglycerides, creatinine, and urea levels. Combined exposure to EtOH with phytocyanin contracted these biochemical alterations. Phycocyanin decreased also EtOH-induced anxiety and ameliorated exploratory behavior assessed by the elevated-plus maze and open field tests respectively.

C-phycocyanin decreases proliferation and migration of melanoma cells: In silico and in vitro evidences.

The incidence and number of deaths caused by melanoma have been increasing in recent years, and the pigment C-phycocyanin (C-PC) appears as a possible alternative to treat this disease. So, the objective of this study was to combine in silico and in vitro analysis to understand the main anti-melanoma pathways exerted by C-PC. We evaluated the ability of C-PC to bind to the main cellular targets related in the progression of melanoma through molecular docking, and the reflection of this bind in the biological effects in the B16F10 cell line through in vitro analysis. Our results showed that C-PC was able to bind BRAF and MEK, which are related to the signal transduction pathway for proliferation and survival. There was also an interaction between C-PC and cyclin-dependent kinase 4 and 6. In vitro analysis demonstrated that C-PC decreased B16F10 cell proliferation, as observed by cell viability and mitotic index assays. C-PC also interacted with matrix metalloproteinase 2 and 9 and N-cadherin, which may have caused the decrease in cell migration observed in vitro. Besides that, C-PC interacts with VEGF, a factor responsible for regulating the proliferation and cellular invasion pathways. Finally, C-PC did not alter the cell viability of the non-tumoral melanocytes. Therefore, C-PC is a strong anti-tumor candidate for the treatment of melanoma, since it acts in different cellular pathways of melanoma, without causing damage to non-tumoral cells.

Anti-Aging Effects of R-Phycocyanin from Porphyra haitanensis on HUVEC Cells and Drosophila melanogaster.

Aging has become a global public health challenge. Many studies have revealed that the excessive generation of ROS and oxidative stress could be the major causative factors contributing to aging. In this study, R-phycocyanin (R-PC) was isolated from Porphyra haitanensis, and its anti-aging ability was explored by natural aging Drosophila melanogaster and H2O2-induced HUVEC cells as the aging model. Results showed that R-PC α and ß subunits expressed have antioxidant activity and can inhibit the generation of radicals, exhibiting a protective effect against H2O2-induced apoptotic HUVEC cells death. R-PC prevented the H2O2-induced HUVEC cell cycle phase arrest by regulating cell cycle-related protein. Furthermore, R-PC prevented the H2O2-induced HUVEC cell cycle phase arrest by regulating cell-cycle-related protein expression. In vivo study also indicated that R-PC significantly increased the survival time and alleviated the oxidative stress of Drosophila melanogaster. Moreover, R-PC notably decreased levels of ROS in natural aging flies and inhibited lipid peroxidation by enhancing the expressions of the endogenous stress marker genes (SOD1, SOD2, CAT of Drosophila melanogaster). Taken together, a study on the antioxidation extract from Porphyra haitanensis, such as R-PC, may open a new window for the prevention of anti-aging.

Phycocyanin Ameliorates Colitis-Associated Colorectal Cancer by Regulating the Gut Microbiota and the IL-17 Signaling Pathway.

Phycocyanin (PC) is a pigment-protein complex. It has been reported that PC exerts anti-colorectal cancer activities, although the underlying mechanism has not been fully elucidated. In the present study, azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mice were orally administrated with PC, followed by microbiota and transcriptomic analyses to investigate the effects of PC on colitis-associated cancer (CAC). Our results indicated that PC ameliorated AOM/DSS induced inflammation. PC treatment significantly reduced the number of colorectal tumors and inhibited proliferation of epithelial cell in CAC mice. Moreover, PC reduced the relative abundance of Firmicutes, Deferribacteres, Proteobacteria and Epsilonbacteraeota at phylum level. Transcriptomic analysis showed that the expression of genes involved in the intestinal barrier were altered upon PC administration, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed the IL-17 signaling pathway was affected by PC treatment. The study demonstrated the protective therapeutic action of PC on CAC.

The Inhibitory Effect of Phycocyanin Peptide on Pulmonary Fibrosis In Vitro.

Phycocyanin is an excellent antioxidant with anti-inflammatory effects on which recent studies are growing; however, its specific target remains unclear. Linear tetrapyrrole compounds such as bilirubin have been shown to lead to the induction of heme oxygenase 1 expression in vivo, thus achieving antioxidant and anti-inflammatory effects. Phycocyanin is bound internally with linear tetrapyrrole phycocyanobilin in a similar structure to bilirubin. We speculate that there is probably a way of inducing the expression of heme oxygenase 1, with which tissue oxidative stress and inflammation can be inhibited, thus inhibiting pulmonary fibrosis caused by oxidative damage and inflammation of lung. By optimizing the enzymatic hydrolysis process, phycocyanobilin-bound phycocyanin peptide were obtained, and its in vitro antioxidant, anti-inflammatory, and anti-pulmonary fibrosis activities were investigated. The results show that the phycocyanobilin peptide was able to alleviate oxidative and inflammatory damage in cells through the Keap1-Nrf2-HO-1 pathway, which in turn relieved pulmonary fibrosis symptoms.

C-Phycocyanin Suppresses Cell Proliferation and Promotes Apoptosis by Regulating the AMPK Pathway in NCL-H292 Non-Small Cell Lung Cancer Cells.

Non-small cell lung cancer (NSCLC) results in high mortality and has gained increasing attention. C-Phycocyanin (C-PC) has been identified as a potential therapeutic inhibitor for NSCLC, but its underlying mechanism remains obscure. The gene expression of the long noncoding RNA neighbour of BRCAI RNA 2 (NBR2) in NSCLC cells was evaluated by quantitative reverse transcription-PCR. The cell capacity for proliferation and migration was examined by EdU and wound-healing assays. Furthermore, the viability and apoptosis of cells was measured with CCK-8 and annexin V/PI, respectively. Next, the protein level of activation of adenosine monophosphate- activated protein kinase and the rapamycin kinase (mTOR) signalling pathway-associated molecules was evaluated by western blotting. H292 cells were pre-treated with C-PC or transfected with plasmids encoding NBR2 or the shNBR2 plasmid, to over-express or knock down NBR2 expression, respectively. NBR2 expression was robustly down-regulated in NSCLC cell lines compared with a normal cell line (BEAS-2B). NBR2 over-expression inhibited migration and promoted apoptosis of H292 cells. Treatment of H292 cells with C-PC enhanced NBR2 levels in a dose- and time-dependent manner. Downregulation of NBR2 in H292 cells inhibited the activity of C-PC on cell proliferation, viability and clone formation. Further mechanistic investigation showed that the down-regulation of NBR2 abolished the modulatory effects of C-PC on the AMPK/mTOR signalling pathway. In conclusion, C-PC inhibits H292 cell growth by enhancing the NBR2/AMPK signalling pathway.

Protective effect of C-phycocyanin and apo-phycocyanin subunit on programmed necrosis of GC-1 spg cells induced by H2 O2.

C-phycocyanin (C-PC) is an effective antioxidant and has an important value in medical research. Oxidative stress is considered to be one of the main underlying mechanisms of cell death, and reducing oxidative stress is one of the strategies to enhance germ cell viability. Herein, we investigated the protective effect and the mechanism of C-PC and apo-phycocyanin subunit on oxidative stress damage induced by H2 O2 in GC-1 spg cells. C-PC genes were cloned into the pGEX-4T-1 vectorand transformed into Escherichia coli BL21 to achieve the efficient expression of C-PC subunit. GC-1 spg cells were treated with 600 µM H2 O2 for 24 h to establish the oxidative stress damage model. Cell viability was detected by CCK-8. The degree of oxidative stress was detected by testing Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and glutathione (GSH) and Malondialdehyde (MDA) levels. Reactive oxygen species (ROS) was evaluated utilizingby 2', 7'-dichlorofluorescent-diacetate (DCFH-DA). Mitochondrial membrane potential was determined by JC-1. Cell necrosis rate was detected by Annexin V-FITC/PI. Expression of protein was detected by western blot. We found that C-PC and GST-CPC ß significantly inhibited H2 O2 -induced oxidative damage of GC-1 spg cells, improved the ability of antioxidation, reduced ROS overproduction, and mitochondrial membrane potential loss, and inhibited the RIP-1/RIP-3/ p-MLKL signaling pathway to reduce the necrosis rate. The results demonstrated that C-PC played a protective role against H2 O2 -induced cell damage, especially its ß subunit. This study provides a theoretical basis for C-PC as a potential protective agent of reproductive system.

The Synbiotic Effect of Probiotics and Dried Spirulina platensis or Phycocyanin on Biofilm Formation by Salmonella Typhimurium and Staphylococcus aureus.

This study aimed to evaluate the synbiotic effect of probiotics and dried Spirulina platensis or phycocyanin on autoaggregation, coaggregation, and the inhibition of biofilm formation by Salmonella Typhimurium and Staphylococcus aureus on 96-well microtiter plates and Human colon carcinoma cells-116 surfaces. The results showed that the probiotics strains cultured in the presence of S. platensis exhibited the highest autoaggregation values, ranging between 68.5 and 74.2% after 24 h. All probiotic strains with or without S. platensis and phycocyanin showed coaggregation abilities with S. Typhimurium and S. aureus. Interestingly, significant effect of S. platensis and phycocyanin supplementation was observed on the inhibition of the biofilm formation by the selected pathogens during the competition, exclusion, and displacement on abiotic and biotic surfaces.

Therapeutic Efficacy of Natural Product 'C-Phycocyanin' in Alleviating Streptozotocin-Induced Diabetes via the Inhibition of Glycation Reaction in Rats.

Diabetes is a long-term metabolic disorder characterized by persistently elevated blood sugar levels. Chronic hyperglycemia enhances glucose-protein interactions, leading to the formation of advanced glycation end products (AGEs), which form irreversible cross-links with a wide variety of macromolecules, and accumulate rapidly in the body tissues. Thus, the objective of this study was to assess the therapeutic properties of C-phycocyanin (C-PC) obtained from Plectonema species against oxidative stress, glycation, and type 2 diabetes mellitus (T2DM) in a streptozotocin (STZ)-induced diabetic Wistar rat. Forty-five days of C-PC administration decreased levels of triglycerides (TGs), blood glucose, glycosylated hemoglobin, (HbA1c), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), liver and kidney function indices, and raised body weight in diabetic rats. C-PC suppressed biochemical glycation markers, as well as serum carboxymethyllysine (CML) and fluorescent AGEs. Additionally, C-PC maintained the redox state by lowering lipid peroxidation and protein-bound carbonyl content (CC), enhancing the activity of high-density lipoprotein cholesterol (HDL-C) and renal antioxidant enzymes, and preserving retinal and renal histopathological characteristics. Thus, we infer that C-PC possesses antidiabetic and antiglycation effects in diabetic rats. C-PC may also act as an antidiabetic and antiglycation agent in vivo that may reduce the risk of secondary diabetic complications.

The Effect of C-Phycocyanin on Microglia Activation Is Mediated by Toll-like Receptor 4.

The blue-green alga Spirulina platensis is rich in phycocyanins, that exhibit a wide range of pharmacological actions. C-phycocyanin (C-PC), in particular, possesses hepatoprotective, nephroprotective, antioxidant, and anticancer effects. Furthermore, several studies have reported both anti- and proinflammatory properties of this pigment. However, the precise mechanism(s) of action of C-PC in these processes remain largely unknown. Therefore, here we explored the C-PC effect in in vitro microglia activation. The effect of C-PC on the expression and release of IL-1ß and TNF-α and the activation of NF-κB was examined in primary microglia by real-time PCR, ELISA, and immunofluorescence. Treatment with C-PC up-regulated the expression and release of IL-1ß and TNF-α. C-PC also promoted the nuclear translocation of the NF-κB transcription factor. Then, to elucidate the molecular mechanisms for the immunoregulatory function of C-PC, we focused on investigating the role of Toll-like receptor 4 (TLR4). Accordingly, several TLR4 inhibitors have been used. Curcumin, ciprofloxacin, L48H37, and CLI-095 that suppresses specifically TLR4 signaling, blocked IL-1ß and TNF-α. Overall, these results indicate the immunomodulatory effect of C-PC in microglia cultures and show for the first time that the molecular mechanism implicated in this effect may involve TLR4 activation.

The Antioxidant Activity of a Commercial and a Fractionated Phycocyanin on Human Skin Cells In Vitro.

The protective effects for cells against chemical and UVA stress of a commercial phycocyanin (PC) for food use and a PC extracted from Arthrospira platensis (Spirulina) in phosphate buffer were assessed. The purity of the commercial PC, spectrophotometrically estimated as A620/A280 and confirmed by HPLC, was higher than that of the fractionated PC (2.0 vs. 1.5) but was twofold less concentrated. The oxygen radical antioxidant capacities (ORACs) of the commercial and fractionated PCs were 12,141 ± 1928 and 32,680 ± 3295 TE/100 g, respectively. The degradation of PCs upon exposure to UVA was spectrophotometrically estimated, and cytotoxicity was evaluated with the MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) test on human fibroblasts and keratinocytes. A lower level of reactive oxygen species (ROS) was recorded in the two cell lines incubated with the commercial PC after menadione treatment (p < 0.01) and UVA exposure (p < 0.001) on fibroblasts after 5 min and keratinocytes up to 25 min, compared with controls. Differently, the fractionated PC was not protective and showed significant (p < 0.01) paradoxical prooxidant effects. Overall, the PC for food consumption demonstrated a high safety threshold and antioxidant ability to cells that, along with its coloring power, make it an excellent candidate for cosmetic formulations.

[Arthrospira platensis: antioxidant, hypoglycemic and hypolipidemic effects in vitro and in vivo (brief review)].

The cyanobacterium Arthrospira platensis biomass is a promising food source of biologically active substances with pharmacological activity. The aim of this research was a brief review and analysis of experimental in vitro and in vivo studies of the antioxidant, hypoglycemic and hypolipidemic properties of A. platensis biomass, phycocyanins, and their chromophore - phycocyanobilin. Material and methods. For the main search of the literature, the PubMed Internet resource was used, the key component of which is the Medline article database, covering about 75% of the world's medical publications. In addition, Scopus and Web of Science databases were used. Search depth - 20 years. Search keywords: Arthrospira platensis, phycobiliprotein, C-phycocyanin, allophycocyanin, hypoglycemic effect, hypolipidemic effect, antioxidant activity, in vitro and in vivo studies. Results. A brief description of the composition of the cyanobacterium Arthrospira platensis biomass, methods of its cultivation, phycocyanins extraction methods is presented. The results of experimental studies indicate the presence of pronounced antioxidant properties of A. platensis biomass, mainly due to phycocyanins in its composition. The hypoglycemic and hypolipidemic effects of A. platensis biomass and extracted phycocyanins intake have been established in vivo when modeling carbohydrate and/or lipid metabolism disorders. The results of in vitro and in vivo studies indicate the presence of pronounced antioxidant properties of phycocyanins. Hypoglycemic effects are shown in particular in experiments on rats with hyperlipidemia and alloxan diabetes fed a diet enriched with A. platensis biomass and on KKAy mice, treated with C-phycocyanin extract. Conclusion. The analysis of the results of in vitro and in vivo studies of the antioxidant, hypoglycemic and hypolipidemic properties of A. platensis biomass and extracts with a high content of phycocyanins, presented in a brief review, suggests that their use in the diet of people with impaired carbohydrate and lipid metabolism is promising. Accordingly, from the standpoint of evidence-based medicine, clinical studies on the use of spirulina biomass and/or its extracts with a high content of phycocyanins as part of specialized foods intended for the prevention and/or dietary correction of carbohydrate and lipid metabolism disorders should be preceded by additional experimental physical-chemical, physiological and biochemical research.

Efficacy of red light for enhanced cell disruption and fluorescence intensity of phycocyanin.

In this study, red LED and urea used as light and nitrogen sources, respectively, for the cultivation of Spirulina to enhance the fluorescence property and purity of phycocyanin. Besides, there is a high concentration of phycocyanin leached out from red light (RL) grown cells than white light (WL) without cell disruption. This type of cultivation reduces the complexity of extraction methods and cost of the downstream process. The fluorescence intensity of C-PC enhanced while using red LEDs and purity ratio improved by single-step cation exchange chromatography. Phycocyanin from red-light-exposed culture exhibited pronounced antibacterial activity against bacteria. The hydrogen peroxide scavenging activity of C-PC (93.7%) is higher than the WL cultures (88.8%). Phycocyanin from RL culture exhibited a strong antiproliferative activity (64.1%) against HeLa cancer cell line. The present study aims to analyze the influence of red light and urea on enhancing the phycocyanin production.

Insulin Receptor Substrate 1 Is Involved in the Phycocyanin-Mediated Antineoplastic Function of Non-Small Cell Lung Cancer Cells.

Phycocyanin, derived from marine algae, is known to have noteworthy antineoplastic properties. However, the underlying mechanism involved in phycocyanin-mediated anti-growth function on non-small cell lung cancer (NSCLC) cells is still ambiguous. Here, we investigated the mechanism of action of phycocyanin on H1299, A549, and LTEP-a2 cells. According to the results obtained, insulin receptor substrate 1 (IRS-1) expression was reduced by phycocyanin. Cell phenotype tests showed that siRNA knockdown of IRS-1 expression significantly inhibited the growth, migration, colony formation, but promoted the apoptosis of NSCLC cells. Meanwhile, phycocyanin and IRS-1 siRNA treatment both reduced the PI3K-AKT activities in NSCLC cells. Moreover, overexpression of IRS-1 accelerated the proliferation, colony formation, and migration rate of H1299, A549, and LTEP-a2 cells, which was contradicting to the knockdown results. Overall, this study uncovered a regulatory mechanism by which phycocyanin inhibited the growth of NSCLC cells via IRS-1/AKT pathway, laying the foundation for the potential target treatment of NSCLC.