Spirulina Extract Enhanced a Protective Effect in Type 1 Diabetes by Anti-Apoptosis and Anti-ROS Production

Phycocyanin as a nature-inspired antidiabetic agent: A systematic review

BACKGROUND

Nutraceuticals have been important for more than two decades for their safety, efficacy, and outstanding effects. Diabetes is a major metabolic syndrome, which may be improved using nutritional pharmaceuticals. Some microalgae species, such as spirulina, stand out by providing biomass with exceptional nutritional properties. Spirulina has a wide range of pharmacological effects, mostly related to phycocyanin. Phycocyanin is a protein compound with antidiabetic properties, known as a nutraceutical.

OBJECTIVE

This review delves into phycocyanin applications in diabetes and its complications and ascertains the mechanisms involved.

METHODS

Scopus, PubMed, Cochrane Library, Web of Science, and ProQuest databases were systematically reviewed (up to April 30, 2023), in which only animal and cellular studies were found.

RESULTS

According to animal studies, the administration of phycocyanin affected biochemical parameters (primary outcome) related to diabetes. These results showed an increase in fasting insulin serum and a decrease in fasting blood glucose, glycosylated serum protein, and glycosylated hemoglobin. In cellular studies, though, phycocyanin prevented methylglyoxal and human islet amyloid polypeptide-induced dysfunction in β-cells and induced apoptosis through different molecular pathways (secondary outcome), including activation of Nrf2, PI3K/Akt, and suppression of JNK and p38. Also, phycocyanin exerted its antidiabetic effect by affecting the pathways regulating hepatic glucose metabolism.

CONCLUSIONS

Thus, based on the available information and literature, targeting these pathways by phycocyanin may unleash an array of benefits, including positive outcomes of the antidiabetic effects of phycocyanin as a nutraceutical.

OTHER

This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) at the National Institute of Health. The registration number is CRD42022307522.

Beneficial effects of Spirulina platensis on mice testis damaged by silver nanoparticles

Silver nanoparticles (AgNPs) have been used widely in medical applications and various industries. Humans could be exposed to the risk of AgNPs toxicity through different routes. The current study aimed to investigate the role of Spirulina platensis (SP) against the side effects of AgNPs on mice testis. Adult male NMRI mice were divided into four groups: control group, SP group (300 mg/kg bwt), AgNPs (20 nm) group (500 mg/kg bwt), Co-treated group (SP + AgNPs). The groups were treated orally for 35 days. Subsequently, epididymal sperm parameters, sperm DNA integrity, daily sperm production (DSP), sexual hormones level, malondialdehyde (MDA), total antioxidant capacity (TAC) and spermatogenesis indices were measured. In addition, the histopathology of testes was evaluated using tissue processing, haematoxylin-eosin staining and stereology techniques. A significant decrease in the number of spermatogenic cells, Leydig cells and sperm parameters was observed in the AgNPs treated group. Serum levels of testosterone and TAC were decreased significantly following AgNPs treatment. Also, MDA incremented in the serum of AgNPs treated mice. The stereological analysis revealed that AgNPs exposure induced histopathological changes in the seminiferous tubules, degeneration and dissociation of spermatogenic cells. In contrast, SP co-administration significantly counteracted AgNPs reproductive toxicity impacts. SP co-exposure caused an increase in spermatogenesis indices, TAC and also a decrease in MDA. SP improved the histopathological changes of testes tissue and spermatozoa abnormalities. In parallel, SP modulated levels of testosterone, FSH and LH. Spirulina platensis exhibited the protective potential by regulating oxidative stress against AgNPs-induced reproductive toxicity. SP could be a candidate therapy against AgNPs reprotoxic impacts.

Reconfiguration of Gut Microbiota and Reprogramming of Liver Metabolism with Phycobiliproteins Bioactive Peptides to Rehabilitate Obese Rats

Phycobiliproteins (derived from Arthrospira platensis) bioactive peptide extracts (PPE) possess multiple pharmacological effects in the mitigation of human metabolic disorders. The role of PPE in the treatment of diet-induced obesity and the understanding of the underlying mechanism between the gut microbiome and metabolic blood circulation for obese patients remains poorly understood. In this study, we showed that PPE attenuated obesity by reducing body weight, and ameliorated glucose and lipid indexes in serum. In particular, PPE is postulated to mitigate liver steatosis and insulin resistance. On the other hand, dietary treatment with PPE was found to “reconfigure” the gut microbiota in the way that the abundances were elevated for Akkermansia_muciniphila, beneficial Lactobacillus and Romboutsia, SCFA-producing species Faecalibacterium prausnitzii, Lachnospiraceae_bacterium, Clostridiales_bacterium, probiotics Clostridium sp., Enterococcus faecium, and Lactobacillus_johnsonii, while the abundance of Firmicutes was reduced and that of Bacteroidetes was increased to reverse the imbalance of Firmicutes/Bacteroidetes ratio. Finally, the metabolomics of circulating serum using UHPLC-MS/MS illustrated that PPE supplementation indeed promoted lipid metabolism in obese rats. As summary, it was seen that PPE reprogrammed the cell metabolism to prevent the aggravation of obesity. Our findings strongly support that PPE can be regarded as a potential therapeutic dietary supplement for obesity.

Arthrospira platensis nanoparticles defeat against diabetes-induced testicular injury in rat targeting, oxidative, apoptotic, and steroidogenesis pathways

Varieties of studies have been used to investigate the health benefits of Spirulina (Arthrospira platensis); however, more research is needed to examine if its nano form may be utilized to treat or prevent several chronic diseases. So, we designed this study to explore the effect and the cellular intracellular mechanisms by which Arthrospira platensis Nanoparticles (NSP) alleviates the testicular injury induced by diabetes in male Wistar rats. Eighty Wistar male rats (n = 80) were randomly allocated into eight groups. Group 1 is untreated rats (control), Group 2 including STZ-induced diabetic rats with 65 mg/kg body weight STZ (STZ-diabetic), Group 3-5: including diabetic rats treated with NSP1, NSP2, and NSP3 at 0.25, 0.5, and 1 mg/kg body weight, respectively, once daily orally by the aid of gastric gavage for 12 consecutive weeks and groups 6-8 include normal rats received NSP (0.25, 0.5, and 1 mg/kg body weight once daily orally. The identical volume of normal saline was injected into both control and diabetic rats. After 12 weeks of diabetes induction, the rats were killed. According to our findings, NSP administration to diabetic rats enhances the total body weight and the weight of testes and accessory glands; in addition, NSP significantly reduced nitric oxide and malondialdehyde in testicular tissue improved sperm parameters. Intriguingly, it raises testicular GSH and SOD activity by a significant amount (p < 0.05). As well, Oral administration of NSP to diabetic rats resulted in a decrease in the blood glucose levels, HA1C, induced in the diabetic group, which overcame the diabetic complications NSP caused down-regulation of apoptotic genes with upregulation of BCL-2 mRNA expression (p < 0.05) and prominent up-regulation of steroidogenesis genes expression level in testes in comparison to the diabetic rats which resulted in improving the decreased levels of testosterone hormone, FSH, and LH induced by diabetes. In the same way, our histopathological findings support our biochemical and molecular findings; in conclusion, NSP exerted a protective effect against reproductive dysfunction induced by diabetes not only through its high antioxidant and hypoglycemic action but also through its down-regulation of Apoptotic genes and up-regulation of steroidogenesis regulatory genes expression level in diabetic testes.

Spirulina- An Edible Cyanobacterium with Potential Therapeutic Health Benefits and Toxicological Consequences

Spirulina is a blue-green algae which is cultivated not only for its maximum protein content but also due to the presence of other essential nutrients such as carbohydrates and vitamins (A, C and E). It is also a storehouse of minerals including iron, calcium, chromium, copper, magnesium, manganese, phosphorus, potassium, sodium and zinc. Simultaneously, γ- linolenic acid (an essential fatty acid), as well as pigments such as chlorophyll A and phycobiliproteins (C-phycocyanin, allophycocyanin and β-carotene), is also a major component of its rich nutritional profile. Spirulina is known to have various promising effects on the prevention of cancer, oxidative stress, obesity, diabetes, cardiovascular diseases and anemia. Moreover, it also plays a positive role in treating muscular cramps. The safety recommended dosage of Spirulina is approximately 3-10 g/d for adults and it's biological value (BV) is 75 with a net protein utilization (NPU) of 62. Spirulina does not have pericardium due to which it does not hinder the absorption of iron by chelation with phytates or oxalates. On the contrasting note, it may have some adverse effects due to the toxins (microcystins, β-methylamino-L-alanine (BMAA)) produced by Spirulina which might contribute to acute poisoning, cancer, liver damage as well as gastrointestinal disturbances. Its long-term consumption may also lead to the pathogenesis of Alzheimer's disease and Parkinson's disease. The current review focuses on the various aspects of spirulina including its cultivation, nutritional composition, extraction techniques, health benefits, adverse effects, industrial scope and market value which could be beneficial for its utilization in the development of value-added products and supplementary foods due to its high content of protein and bioavailability of nutrients.

Wide Range Applications of Spirulina: From Earth to Space Missions

Spirulina is the most studied cyanobacterium species for both pharmacological applications and the food industry. The aim of the present review is to summarize the potential benefits of the use of Spirulina for improving healthcare both in space and on Earth. Regarding the first field of application, Spirulina could represent a new technology for the sustainment of long-duration manned missions to planets beyond the Lower Earth Orbit (e.g., Mars); furthermore, it could help astronauts stay healthy while exposed to a variety of stress factors that can have negative consequences even after years. As far as the second field of application, Spirulina could have an active role in various aspects of medicine, such as metabolism, oncology, ophthalmology, central and peripheral nervous systems, and nephrology. The recent findings of the capacity of Spirulina to improve stem cells mobility and to increase immune response have opened new intriguing scenarios in oncological and infectious diseases, respectively.

The protective effect of manganese superoxide dismutase from thermophilic bacterium HB27 on hydrochloric acid-induced chemical cystitis in rats

Purpose

To evaluate the effects of manganese superoxide dismutase (Mn-SOD) from thermophilic bacterium HB27 (name as Tt-SOD) on chemical cystitis.

Methods

Control and experimental rats were infused by intravesical saline or hydrochloric acid (HCl) on the first day of the experiments. Saline, sodium hyaluronate (SH) or Tt-SOD were infused intravesically once a day for three consequent days. On the fifth day, the rats were weighted and sacrificed following a pain threshold test. The bladder was harvested for histological and biochemical analyses.

Results

Tt-SOD could reduce the bladder index, infiltration of inflammatory cells in tissues, serum inflammatory factors and SOD levels, mRNA expression of inflammatory factors in tissues, and increase perineal mechanical pain threshold and serum MDA and ROS levels in HCl-induced chemical cystitis. Furthermore, Tt-SOD alleviated inflammation and oxidative stress by the negative regulation of the NF-κB p65 and p38 MAPK signaling pathway.

Conclusions

Intravesical instillation of Tt-SOD provides protective effects against HCl-induced cystitis.

Arthrospira maxima (Spirulina) prevents endoplasmic reticulum stress in the kidney through its C-phycocyanin

Arthrospira maxima (Spirulina) is a cyanobacterium which is considered a nutraceutical because it has antioxidant, anti-inflammatory, and cytoprotective properties in different renal disease models (Rodriguez-Sánchez et al., 2012; Aziz et al., 2018; Memije-Lazaro et al., 2018). The therapeutic effects are due to the presence of metabolites with biological effects similar to those of essential fatty acids ω-3 and ω-6, vitamins A, C and E, and accessory pigments such as phycobiliproteins. One of the most abundant phycobiliproteins in A. maxima is C-phycocyanin (Mysliwa-Kurdziel and Solymosi, 2017). This molecule is responsible for nephroprotective action in a model of acute kidney injury (AKI) because it reduces oxidative stress and caspase activation (Rodriguez-Sánchez et al., 2012; Rojas-Franco et al., 2018). However, both A. maxima and its C-phycocyanin are related to the reduction of the redox environment. Thus, they probably help to maintain the adequate function of the intracellular organelles like the endoplasmic reticulum. However, this therapeutic action has not been evaluated previously.

Effect of Microalgae Arthrospira on Biomarkers of Glycemic Control and Glucose Metabolism: A Systematic Review and Meta-analysis

Diabetes mellitus and insulin resistance are associated with an increased risk of cardiovascular disease (CVD) incidence and a higher rate of CVD-related death. In this study, the effects of Arthrospira (Spirulina) a blue-green algae supplementation on biomarkers of glycemic control and glucose metabolism has been evaluated. PubMed, Scopus, and ISI Web of Science were searched systematically of English human subjects and PubMed for pre-clinical animal studies (rats and mice) from January 2008 until November 2020. The pooled weighted mean difference (MD) and its 95% confidence interval (CI) were calculated and pooled using a random-effect model. Seven clinical and 27 preclinical studies were included. Pooled results of the clinical studies showed that Arthrospira supplementation significantly reduced the fasting blood sugar (FBS): (0.63- 2.90-) 1.77-, total cholesterol (TC): (0.46- ، 4.61-) 2.54-, triglycerides (TG): (0.89- ، 6.54-) 3.71- and increased the high-density lipoprotein cholesterol (HDL-C): (3.86 ، 0.67) 2.27; however, Arthrospira was not significantly effective in terms of reducing the glycated hemoglobin A1c (HbA1C): (1.04 ، 2.23-) 0.59- and low-density lipoprotein cholesterol (LDL-C). Pooled results of preclinical studies showed that Arthrospira supplementation reduced FBS [-10.31 (-12.49, -8.13)] and HbA1C [-5.12 (-8.06, -2.19)] significantly in diabetic animals. Sub-group analysis of clinical studies showed that intervention duration less than 2 months [-2.52 (-4.37, -0.67)] and the dose less than 2 gram [-3.22 (-5.67, -0.76)] showed significant improvement in terms of reducing the FBS in humans. It can be concluded that Arthrospira can be considered as an effective FBS, TG, TC, and HDL-C adjusting nutraceutical agent for diabetes mellitus. Due to the differences in the results of clinical and animal studies in terms of HbA1c, more studies are needed for a definitive conclusion.

Protective impact of Spirulina platensis against γ-irradiation and thioacetamide-induced nephrotoxicity in rats mediated by regulation of micro-RNA 1 and micro-RNA 146a

Chronic kidney disease develops popular and medical health problems, especially in developing countries. The objective of this study is to investigate the protective mechanism of Spirulina platensis against γ-irradiation (R) and/or thioacetamide (TAA)-induced nephrotoxicity in rats. Rats intoxicated with R or TAA showed alterations in kidney function markers (urea, creatinine, albumin, and total protein contents), oxidative stress markers (malondialdehyde, reduced glutathione), antioxidant enzymes (superoxide dismutase, catalase), and several inflammatory markers (including, the high-sensitivity C-reactive protein, hypoxia-inducible factor-1 alpha, tumor necrosis factor-alpha, interferon-gamma, some interleukins, and nuclear factor-kappa B). Rats also acquired apoptosis, evinced by high caspase-3 efficacy. This nephrotoxicity mediated by upregulation of the messenger RNA (mRNA) gene expression of the autophagy markers: Beclin-1, microtubule-associated protein LC3, p62 binding protein, immunoglobulin G receptor Fcγ receptor (FcγR), micro-RNA-1 (miR-1), protein expression of phospho-adenosine monophosphate-activated protein kinase, and phospho-mammalian target of rapamycin, along with downregulation of miR-146a mRNA gene expression and alteration of calcium and iron levels. The combined treatment R/TAA enhanced the observed oxidative stress, inflammation, apoptosis, and autophagy that mediated by higher upregulation of miR-1 and downregulation of miR-146a mRNA gene expression. Spirulina platensis administration exhibited a nephroprotective impact on R, TAA, and R/TAA toxicities via regulating miR-1 and miR-146a mRNA gene expression that monitored adenosine monophosphate-activated protein kinase/mammalian target of rapamycin signaling.

Marine cyanobacterium Spirulina maxima as an alternate to the animal cell culture medium supplement

Serum is a stable medium supplement for in vitro cell culture. Live cells are used in stem cell research, drug toxicity and safety testing, disease diagnosis and prevention, and development of antibiotics, drugs, and vaccines. However, use of serum in culture involves concerns such as an ethical debate regarding the collection process, lack of standardized ingredients, and high cost. Herein, therefore, we evaluated the possibility of using edible cyanobacterium (Spirulina maxima), which is a nutrient-rich, sustainable, and ethically acceptable source, as a novel substitute for fetal bovine serum (FBS). H460 cells were cultured to the 10th generation by adding a mixture of spirulina animal cell culture solution (SACCS) and FBS to the culture medium. Cell morphology and viability, cell cycle, apoptosis, proteomes, and transcriptomes were assessed. We observed that SACCS had better growth-promoting capabilities than FBS. Cell proliferation was promoted even when FBS was replaced by 50-70% SACCS; there was no significant difference in cell shape or viability. There were only slight differences in the cell cycle, apoptosis, proteomes, and transcriptomes of the cells grown in presence of SACCS. Therefore, SACCS has the potential to be an effective, low-cost, and eco-friendly alternative to FBS in in vitro culture.

Phytochemical and Biological Evaluation of a Newly Designed Nutraceutical Self-Nanoemulsifying Self-Nanosuspension for Protection and Treatment of Cisplatin Induced Testicular Toxicity in Male Rats

The incorporation of cisplatin (CP) as a cytotoxic antineoplastic agent in most chemotherapeutic protocols is a challenge due to its toxic effect on testicular tissues. Natural compounds present a promising trend in research, so a new nutraceutical formulation (NCF) was designed to diminish CP spermatotoxicity. A combination of three nutraceutical materials, 250 mg Spirulina platensis powder (SP), 25 mg Tribulus terrestris L. extract (TT), and 100 mg fish oil (FO) were formulated in self-nanoemulsifying self-nanosuspension (SNESNS). SP was loaded into the optimized self-nanoemulsifying system (30% FO, 50% span 80/cremophor EL and 20% isopropanol) and mixed with TT aqueous solution to form SNESNS. For the SP, phytochemical profiling revealed the presence of valuable amounts of fatty acids (FAs), amino acids, flavonoids, polyphenols, vitamins, and minerals. Transmission electron microscopy (TEM) and particle size analysis confirmed the formation of nanoemulsion-based nanosuspension upon dilution. Method validation of the phytochemical constituents in NCF has been developed. Furthermore, NCF was biologically evaluated on male Wistar rats and revealed the improvement of spermatozoa, histopathological features, and biochemical markers over the CP and each ingredient group. Our findings suggest the potential of NCF with SNESNS as a delivery system against CP-induced testicular toxicity in male rats.

Biochemical and Molecular Investigation of In Vitro Antioxidant and Anticancer Activity Spectrum of Crude Extracts of Willow Leaves Salix safsaf

Organic fractions and extracts of willow (Salix safsaf) leaves, produced by sequential solvent extraction as well as infusion and decoction, exhibited anticancer potencies in four cancerous cell lines, including breast (MCF-7), colorectal (HCT-116), cervical (HeLa) and liver (HepG2). Results of the MTT assay revealed that chloroform (CHCl₃) and ethyl acetate (EtOAc)-soluble fractions exhibited specific anticancer activities as marginal toxicities were observed against two non-cancerous control cell lines (BJ-1 and MCF-12). Ultra-high-resolution mass spectrometry Q-Exactive™ HF Hybrid Quadrupole-Orbitrap™ coupled with liquid chromatography (UHPLC) indicated that both extracts are enriched in features belonging to major phenolic and purine derivatives. Fluorescence-activated cell sorter analysis (FACS), employing annexin V-FITC/PI double staining indicated that the observed cytotoxic potency was mediated via apoptosis. FACS analysis, monitoring the increase in fluorescence signal, associated with oxidation of DCFH to DCF, indicated that the mechanism of apoptosis is independent of reactive oxygen species (ROS). Results of immunoblotting and RT-qPCR assays showed that treatment with organic fractions under investigation resulted in significant up-regulation of pro-apoptotic protein and mRNA markers for Caspase-3, p53 and Bax, whereas it resulted in a significant reduction in amounts of both protein and mRNA of the anti-apoptotic marker Bcl-2. FACS analysis also indicated that pre-treatment and co-treatment of human amniotic epithelial (WISH) cells exposed to the ROS H₂O₂ with EtOAc fraction provide a cytoprotective and antioxidant capacity against generated oxidative stress. In conclusion, our findings highlight the importance of natural phenolic and flavonoid compounds with unparalleled and unique antioxidant and anticancer properties.

Screening of Contaminants of Emerging Concern in Microalgae Food Supplements

The frenetic lifestyle in the developed countries has driven us to be deficient in some nutrients, which may be overcome by supplements. Microalgae, like spirulina (Arthrospira platensis) and chlorella (Chlorella ssp.) are widely used as supplements due to their high contents of macro- and micronutrients. Chlorella and spirulina can be grown naturally in a range of water bodies, showing their high adaptability to harsh environments. They are mainly produced in countries with poor water quality and sometimes inexistent water legislation, which can be a vector of micropollutant introduction into the food chain. Thus, a method for the simultaneous determination of 31 emerging contaminants commonly found as micropollutants in freshwater (pharmaceutical and personal care products, hormones, flame retardants and biocides) in two microalgae is presented. Target contaminants were extracted from the microalgae employing ultrasound-assisted matrix solid-phase dispersion followed by gas chromatography-mass spectrometry analysis. The method was validated for chlorella and spirulina with recoveries ranging from 70% to 111% at concentrations of 25 and 100 ng·g−1, and good linearity in the range from 5 to 400 ng·g−1 with limits of detection below 2.5 ng·g−1, in both microalgae. The method validated was applied to a range of microalgae supplement foods and the results proved that the compounds studied were below limits of detection.

Protective Role of Spirulina platensis Against Bifenthrin-Induced Reprotoxicity in Adult Male Mice by Reversing Expression of Altered Histological, Biochemical, and Molecular Markers Including MicroRNAs

: The potential reprotoxicity of bifenthrin remains unclear if only the common clinical indicators of reproductive disease are examined. The present study aimed to investigate the efficacy of Spirulina platensis, a microalga rich in antioxidant compounds, against bifenthrin-induced testicular oxidative damage in male mice. At the first, we demonstrate that administration of bifenthrin resulted in a decline of testosterone level and in deterioration of sperm quality that was correlated with significant transcription changes of some specific mRNA and microRNA involved in cholesterol transport, testosterone synthesis, and spermatogenesis. At the biochemical level, we found that oxidative stress was obvious in the bifenthrin group, as evidenced by increase in malondialdehyde (MDA), protein carbonyls (PCO), reactive oxygen species (ROS), and nitrite oxide (NO) that was correlated with activation of genes related to mitochondrial apoptotic signal pathways. We then brought, for the first time to our knowledge, solid and complete experimental evidences that administration of mice with Spirulina extract was sufficient to protect against deleterious effects BF in testicular tissues by abrogating the change in antioxidant enzyme activities; the increase in MDA, PCO, and NO concentrations; and the altered expression level of miRNA and mRNA involved in spermatogenesis. We finally demonstrate that Spirulina restores the production of testosterone in mice as well as epididymal sperm viability and motility. These results suggest a potential antitoxic activity of Tunisian Spirulina deserving further attention.

A novel two-phase bioprocess for the production of Arthrospira (Spirulina) maxima LJGR1 at pilot plant scale during different seasons and for phycocyanin induction under controlled conditions

A two-phase outdoor cultivation bioprocess for Arthrospira maxima LJGR1 combined with phycocyanin induction in concentrated cultures under controlled conditions was evaluated using a modified low-cost Zarrouk medium. Growth was monitored during 4 cycles in 2018 and 4 cycles in 2019. Biomass was harvested and concentrated using membrane technology at the end of each cycle for further phycocyanin induction using blue LED light (controlled conditions, 24 h). The highest biomass productivity was observed during spring and summer cycles (13.63-18.97 g_DWm^-2 d^-1); during mid-fall and mid-end fall, a decrease was observed (9.93-7.76 g_DWm^-2 d^-1). Under favorable growth conditions, phycocyanin induction was successful. However, during cycles with unfavorable growth condition, phycocyanin induction was not observed. Reactive-grade phycocyanin (3.72 ± 0.14) was recovered and purified using microfiltration and ultrafiltration technologies.

Microalgae aqueous extracts exert intestinal protective effects in Caco-2 cells and dextran sodium sulphate-induced mouse colitis

Aqueous extracts from Chlorella pyrenoidosa, Spirulina platensis and Synechococcus sp. PCC 7002 showed gut protective potential in vitro and in vivo.

Protective Action of Ostreococcus tauri and Phaeodactylum tricornutum Extracts towards Benzo[a]Pyrene-Induced Cytotoxicity in Endothelial Cells

Marine microalgae are known to be a source of bioactive molecules of interest to human health, such as n-3 polyunsaturated fatty acids (n-3 PUFAs) and carotenoids. The fact that some of these natural compounds are known to exhibit anti-inflammatory, antioxidant, anti-proliferative, and apoptosis-inducing effects, demonstrates their potential use in preventing cancers and cardiovascular diseases (CVDs). Benzo[a]pyrene (B[a]P), a polycyclic aromatic hydrocarbon (PAH), is an ubiquitous environmental pollutant known to contribute to the development or aggravation of human diseases, such as cancer, CVDs, and immune dysfunction. Most of these deleterious effects are related to the activation of the polycyclic aromatic hydrocarbon receptor (AhR). In this context, two ethanolic microalgal extracts with concentrations of 0.1 to 5 µg/mL are tested, Ostreoccoccus tauri (OT) and Phaeodactylum tricornutum (PT), in order to evaluate and compare their potential effects towards B[a]P-induced toxicity in endothelial HMEC-1 cells. Our results indicate that the OT extract can influence the toxicity of B[a]P. Indeed, apoptosis and the production of extracellular vesicles were decreased, likely through the reduction of the expression of CYP1A1, a B[a]P bioactivation enzyme. Furthermore, the B[a]P-induced expression of the inflammatory cytokines IL-8 and IL1-β was reduced. The PT extract only inhibited the expression of the B[a]P-induced cytokine IL-8 expression. The OT extract therefore seems to be a good candidate for counteracting the B[a]P toxicity.

Ficus carica leaves extract inhibited pancreatic β-cell apoptosis by inhibiting AMPK/JNK/caspase-3 signaling pathway and antioxidation

The aim of this study was to explore the inhibitory effects of Ficus carica leaves (FCL) extract on AMPK/JNK/caspase3 signaling pathway and antioxidation in pancreatic β-cells. H&E staining, insulin immunohistochemistry, and TUNEL methods were used to investigate the effects of FCL on pancreatic histopathology in type 1 diabetic mice. The expression levels of caspase-3, AMPK, and JNK protein in the pancreatic tissue and MIN6 cells [induced by palmitic acid (PA) and hydrogen peroxide] were determined. Flow cytometry was used to detect the effects of FCL on apoptosis and ROS production of MIN6 cells. FCL (2 g/kg, continuous gavage for 6 weeks) significantly improved the pancreatic tissue injury in type 1 diabetic mice and reduced the expression levels of apoptosis-related proteins such as FasL, caspase8, Bax/Bcl-2, Cyt-C, caspase-3, p-AMPK, and p-JNK. FCL inhibited cell apoptosis induced by PA and the protein expression levels of caspase-3, p-AMPK, and p-JNK. The AMPK agonist AICAR could reverse the protective effects of FCL on MIN6 cells. The AMPK inhibitor compound C had a similar effect on MIN6 cells as that of FCL. FCL could inhibit cell apoptosis induced by hydrogen peroxide and reduced the production of ROS. In conclusion, FCL could inhibit pancreatic β-cell apoptosis by inhibiting the AMPK/JNK/caspase-3 signaling pathway and by antioxidation properties.

Crude protein from spirulina increases the viability of CCD‑986sk cells via the EGFR/MAPK signaling pathway

Spirulina, an edible blue-green alga, has great potential for various applications in human health, possibly including reduced skin aging. The mechanisms by which spirulina crude protein (SPCP) may influence human skin fibroblast viability are not yet understood; therefore, a human dermal fibroblast cell line (CCD-986sk) was used as a cell model system to study the influence of SPCP on human skin fibroblast viability. An enzyme-linked immunosorbent assay showed that collagen formation improved in SPCP-treated cells in a dose-dependent manner, while elastase activity was decreased. In addition, western blot analysis showed a dose-dependent decrease in the expression of the aging-associated gene matrix metalloproteinase-8, a collagen-degradative enzyme. It was also shown that SPCP upregulated epidermal growth factor receptor (EGFR) activity, leading to activation of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) signaling pathway. Together, these results demonstrated that SPCP increases human fibroblast viability by activation of the EGFR/MAPK signaling pathway. This contribution sheds light on the molecular mechanism for SPCP increasing the viability of human skin cell and provides a potential efficient cosmeceutical for protecting human skin.

Spirulina platensis attenuates furan reprotoxicity by regulating oxidative stress, inflammation, and apoptosis in testis of rats

Furan is a common food contaminant and environmental pollutant. Spirulina platensis (SP) is a blue-green algae extensively used as therapeutic and health supplements. This study aimed to explore the probable beneficial role of SP against the influence of furan on reproductive system of male rats. Adult male rats were divided into control, vehicle control, SP (300 mg/kg bwt/ day, 7 days), furan (16 mg/kg bwt/ day,30 day), SP/furan, furan/SP and furan+SP groups. Hematology, sperm count, sperm morphology, serum testosterone (TES), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and estradiol (E2) levels, reduced glutathione (GSH), malondialdehyde (MDA), testicular enzymes, and pro inflammatory cytokines were estimated. In addition, histopathology of testis and seminal vesicles and apoptosis were evaluated. Anaemia, leukocytosis, and reduced gonadosomatic index were observed in the furan treated group. TES, LH, FSH, E2, and GSH were significantly decreased following furan treatment. MDA, testicular enzymes, and pro inflammatory cytokines were significantly incremented in testis of furan treated rats. Furan induced apoptic changes in testis. SP significantly counteracted furan reprotoxic impacts, particularly at co-exposure. Conclusively, these findings verified that SP could be candidate therapy against furan reprotoxic impacts.

Renoprotective effect of Spirulina platensis extract against nicotine-induced oxidative stress-mediated inflammation in rats

BACKGROUND

Nicotine is an important factor in the pathogenesis of renal injury in smokers.

PURPOSE

The purpose of the present study was to investigate the renoprotective effect of Spirulina platensis extract (SP) against chronic nicotine administration in rats.

METHODS

Nicotine intoxication was induced with 0.5 mg/kg BW. Rats received 500 mg SP/kg BW by gastric gavage over 4 weeks.

RESULTS

Our data revealed that nicotine induced renal dysfunction manifested by significant abnormal levels of kidney function markers (creatinine and urea) accompanied by increased levels of oxidative stress biomarker (malondialdehyde) and inflammatory markers (nitric oxide, Interleukin-6 and tumor necrosis factor-α) while antioxidant status as glutathione level and glutathione S-transferase activity were found to be decreased significantly as compared with controls. It is worthy to note that nicotine toxicity induced significant increments in the protein expression levels of nuclear factor kappa B as well as caspase-3. Histopathological observations showed tubular necrosis and congestion in the endothelial lining glomerular tuft and epithelial lining renal tubules with nicotine intoxication. Interestingly, our data demonstrated that SP supplementation significantly improved the nicotine-induced kidney dysfunction, alleviated the induced-lipid peroxidation, inflammatory, apoptotic protein markers, and boosted the enzymatic/non-enzymatic antioxidants. Moreover, it attenuated the nicotine-induced histopathological alterations of the kidney architecture.

CONCLUSION

Thus, it is tempting to recommend dietary approaches with Spirulina platensis extract for smokers to minimize the deleterious effect of chronic nicotine consumption and smoke exposure-related problems towards kidney injury via the antioxidant, anti-inflammatory and antiapoptotic properties of Spirulina platensis.

Anti-Diabetic Effects of Acankoreagenin from the Leaves of Acanthopanax Gracilistylus Herb in RIN-m5F Cells via Suppression of NF-κB Activation

Diabetes mellitus is a chronic degenerative disease that causes long-term complications and represents a serious public health problem. In this manuscript, acankoreagenin isolated from the leaves of Acanthopanax gracilistylus (LAG) is thought to possess excellent anti-diabetic properties. In vitro, anti-diabetic activities were assessed based on the inhibitory activities with α-glucosidase (IC₅₀ 13.01 μM), α-amylase (IC₅₀ 30.81 μM), and PTP1B (IC₅₀ 16.39 μM). Acankoreagenin showed better anti-diabetic effects. Then, an investigation was performed to analyze the insulin secretion effects of the insulin-secreting cell line in RIN-m5F cells. It was found that acankoreagenin could increase the insulin release in RIN-m5F cells. It was also found that acankoreagenin reduced NO production, activity of caspase-3, and the reactive oxygen species levels in the cells injured by processing of cytokines. In western blotting, inactivation of NF-κB signaling was confirmed. Acankoreagenin (20 μM) showed a higher I-κBα expression and lower NF-κB expression than the control group and showed a better expression than the positive control L-NAME (1 mM) (p < 0.05). This study demonstrates the anti-diabetic effects of acankoreagenin in vitro and suggests acankoreagenin might offer therapeutic potential for treating diabetes mellitus.

Anti-obesity effects of Spirulina maxima in high fat diet induced obese rats via the activation of AMPK pathway and SIRT1

Spirulina maxima improved the obese phenotype in high fat diet induced rats by activating AMPK and SIRT1.