Spirulina Lipids Alleviate Oxidative Stress and Inflammation in Mice Fed a High-Fat and High-Sucrose Diet

Anti-Glycation Properties of Zinc-Enriched Arthrospira platensis (Spirulina) Contribute to Prevention of Metaflammation in a Diet-Induced Obese Mouse Model

Advanced glycation end products (AGEs) exert a key pathogenic role in the development of obesity and insulin resistance. Thanks to its abundance in bioactive compounds, the microalga Arthrospira platensis (spirulina, SP) is proposed as a nutritional supplement. Here, we investigated the potential anti-glycating properties of SP enriched with zinc (Zn-SP) and the following impact on diet-induced metabolic derangements. Thirty male C57Bl6 mice were fed a standard diet (SD) or a high-fat high-sugar diet (HFHS) for 12 weeks, and a subgroup of HFHS mice received 350 mg/kg Zn-SP three times a week. A HFHS diet induced obesity and glucose intolerance and increased plasma levels of pro-inflammatory cytokines and transaminases. Zn-SP administration restored glucose homeostasis and reduced hepatic dysfunction and systemic inflammation. In the liver of HFHS mice, a robust accumulation of AGEs was detected, paralleled by increased expression of the main AGE receptor (RAGE) and depletion of glyoxalase-1, whereas Zn-SP administration efficiently prevented these alterations reducing local pro-inflammatory responses. 16S rRNA gene profiling of feces and ileum content revealed altered bacterial community structure in HFHS mice compared to both SD and HFHS + Zn-SP groups. Overall, our study demonstrates relevant anti-glycation properties of Zn-SP which contribute to preventing AGE production and/or stimulate AGE detoxification, leading to the improvement of diet-related dysbiosis and metabolic derangements.

The Effects of Spirulina Supplementation on Cardiometabolic Risk Factors: A Narrative Review

Spirulina (Arthrospira platensis) is a cyanobacterium associated with multiple health benefits. Cardiometabolic diseases such as cardiovascular disease, nonalcoholic fatty liver disease, and diabetes are prevalent yet usually preventable non-communicable diseases. Modifiable risk factors for cardiometabolic diseases include excessive body weight, body inflammation, atherogenic lipid profile, and imbalanced glucose metabolism. This review explores the effects of spirulina on cardiometabolic diseases risk factors. Spirulina was effective in reducing body weight, body mass index, and waist circumference, with a potential dose-dependent effect. It also decreased interleukin 6, an important biomarker of body inflammation, by inhibiting NADPH oxidase enzyme, and lowering insulin resistance. spirulina supplementation also reduced triglycerides, low-density lipoprotein cholesterol, and increased high-density lipoprotein cholesterol. Additionally, spirulina reduced fasting blood sugar and post-prandial blood sugar and increased insulin sensitivity, but no effect was observed on glycated hemoglobin A1c. The diverse nutrients, such as phycocyanin, gamma-linolenic acid, and vitamin B12, present in spirulina contribute to its cardiometabolic benefits. The doses used are heterogeneous for most studies, ranging from 1 to 8 grams daily, but most studies administered spirulina for 3 months to observe an effect. The collective evidence suggests that spirulina supplements may help improve risk factors for cardiometabolic diseases, thus, preventing its development. However, due to the heterogeneity of the results, more randomized clinical trials are needed to draw robust conclusions about spirulina's therapeutic potential in ameliorating risk factors for cardiometabolic diseases and fully elucidate the mechanisms by which it exerts its effects.

Systemic lupus erythematosus: latest insight into etiopathogenesis

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder of unknown etiology. Multifactorial interaction among various susceptible factors such as environmental, hormonal, and genetic factors makes it more heterogeneous and complex. Genetic and epigenetic modifications have been realized to regulate the immunobiology of lupus through environmental modifications such as diet and nutrition. Although these interactions may vary from population to population, the understanding of these risk factors can enhance the perception of the mechanistic basis of lupus etiology. To recognize the recent advances in lupus, an electronic search was conducted among search engines such as Google Scholar and PubMed, where we found about 30.4% publications of total studies related to genetics and epigenetics, 33.5% publications related to immunobiology and 34% related to environmental factors. These outcomes suggested that management of diet and lifestyle have a direct relationship with the severity of lupus that influence via modulating the complex interaction among genetics and immunobiology. The present review emphasizes the knowledge about the multifactorial interactions between various susceptible factors based on recent advances that will further update the understanding of mechanisms involved in disease pathoetiology. Knowledge of these mechanisms will further assist in the creation of novel diagnostic and therapeutic options.

Hypocholesterolemic, Antioxidative, and Anti-Inflammatory Effects of Dietary Spirulina platensisis Supplementation on Laying Hens Exposed to Cyclic Heat Stress

This study aimed to investigate the role of dietary Spirulina platensis (SP) supplementation in relieving the negative impacts of heat stress (HS) on the productive performance, cholesterol profile, redox status, and inflammatory cytokines of laying hens. A total of 288, 45-wk-old and 1550.7 ± 2.3 g initial body weight, HY-Line W-36 laying hens were housed in two environmental-controlled compartments. Layers were allotted to eight treatments of a two × four factorial design, with six replicates containing six birds per treatment. The temperature in one of the compartments was kept at a thermoneutral condition (24 °C group), while the temperature in the other compartment was raised to a cyclic heat stress of 35 °C from 9:00 a.m. to 5.00 p.m. (35 °C group). Layers in each compartment were fed on one of four experimental diets, containing 0%, 3%, 6%, or 9% SP (SP groups). The trial continued for five weeks. As a result of this study, exposure of laying hens to cyclic HS resulted in a significant (p < 0.05) increase in the total cholesterol (CH), low-density lipoprotein-CH, liver- and egg yolk-CH, ceruloplasmin, malondialdehyde, interleukins (IL-1β and IL-6), and tumor necrosis factor-α, and a significant (p < 0.05) decrease in the high-density lipoprotein-CH, total antioxidant capacity, and reduced glutathione levels. HS negatively (p < 0.05) affected the hen−day egg production (EP, 90.5% vs. 77.0%), egg weight (EW, 61.8 g vs. 56.8 g), feed intake (FI, 111.6 g vs. 101.5 g) and feed conversion ratio (FCR, 2.00 vs. 2.37). As SP levels increased in layer diets, a linear (p < 0.05) improvement response in most of the parameters was obtained in both HS and non-HS layers, recording the best results with 9% SP (e.g., 78.8% vs. 87.6% EP, 56.7 g vs. 61.9 g EW, 103.3 g vs. 110.2 g FI, and 2.38 vs. 2.04 FCR, in 0% vs. 9% SP, respectively). When incorporating SP into the diets of HS-layers, the negative impacts of HS were remarkably relieved (p < 0.05). Therefore, diets containing 9% SP could be used as a promising approach to improve the productive and physiological performance of laying hens, particularly under heat stress conditions.

Crossbred Sows Fed a Western Diet during Pre-Gestation, Gestation, Lactation, and Post-Lactation Periods Develop Signs of Lean Metabolic Syndrome That Are Partially Attenuated by Spirulina Supplementation

Excessive dietary intake of fats and sugars (“Western diet”, WD) is one of the leading causes of obesity. The consumption of the microalga Arthrospira platensis (spirulina, Sp) is increasing due to its presumed health benefits. Both WD and Sp are also consumed by pregnant and breastfeeding women. This study investigated if gestating and lactating domestic pigs are an appropriate model for WD-induced metabolic disturbances similar to those observed in humans and if Sp supplementation may attenuate any of these adverse effects. Pigs were fed a WD high in fat, sugars, and cholesterol or a control diet. Half of the animals per diet group were supplemented with 20 g Sp per day. The WD did not increase body weight or adipose tissue accumulation but led to metabolic impairments such as higher cholesterol concentration in plasma, lower IGF1 plasma levels, and signs of hepatic damage compared to the control group. Spirulina supplementation could not reduce all the metabolic impairments observed in WD-fed animals. These findings indicate limited suitability of gestating and lactating domestic pigs as a model for WD but a certain potential of low-dose Sp supplementation to partially attenuate negative WD effects.

The Effects of Maternal Intake of EPA and DHA Enriched Diet During Pregnancy and Lactation on Offspring’s Muscle Development and Energy Homeostasis

EPA and DHA are n-3 long-chain polyunsaturated fatty acids with a diversity of health benefits on offspring. The objective of this study was to test the in vivo effect of maternal ingestion of EPA and DHA on fetal and offspring muscle development and energy balance. Two groups of female C57BL/6 mice were fed EPA and DHA enriched diet (FA) and diet devoid of EPA and DHA (CON) respectively throughout the entire period of gestation and lactation. Embryos at E13 and offspring at age of D1 and D21 were selected for sample collection and processing. No change in birth number and body weight were observed between groups at D1 and D21. Transient increase in the expression levels of myogenesis regulating genes was detected at D1 (p < 0.05) in FA group. Most of the expression of muscle protein synthesis regulating genes were comparable (p > 0.05) between FA and CON groups at D1 and D21. The significant increase in MHC4, and IGF-1 was not linked to increased muscle mass. A persistent increase in ISR expression (p < 0.05) but not in GLUT-4 (p > 0.05) was detected in offspring. Up-regulation of adipogenesis regulating genes was accompanied by increasing intramuscular fat accumulation in the offspring of FA group. Considerable increase in transcripts of genes regulating lipid catabolism and thermogenesis in liver (p < 0.05) was noticed in FA group at D21; whereas, only the levels of carnitine palmitoyl transferase 1A (Cpt1α) and Enoyl-CoA Hydratase And 3-Hydroxyacyl CoA Dehydrogenase (Ehhadh) increased at D1. Similarly, genes regulating lipolysis were highly expressed at D21 in FA group. EPA and DHA treatment promoted BAT development and activity by increasing the expression of BAT signature genes (p < 0.05). Also, maternal intake of EPA and DHA enriched diet enhanced browning of sWAT. Taken together, maternal ingestion of EPA/DHA may be suggested as a therapeutic option to improve body composition and counteract childhood obesity- related metabolic disorders and confer lifelong positive metabolic impact on offspring.

SiNiSan alleviates liver injury by promoting hepatic stem cell differentiation via Wnt/β-catenin signaling pathway

BACKGROUND

SiNiSan, a Traditional Chinese Medicine containing Radix Bupleuri, Radix Paeoniae Alba, Fructus Aurantii Immaturus, and Radix Glycyrrhizae, has been shown to be clinically effective in treating liver damage, its underlying molecular mechanisms however remains unclear.

PURPOSE

The aim of the current study was to understand the molecular mechanisms of SiNiSan in the treatment of liver damage utilizing mice and cell culture models.

METHODS

Here, mice were gavaged with 0.2% CCl4 to obtain acute liver injury model and with alcohol to obtain chronic liver injury model. H&E staining was performed to detect liver histomorphology. HPLC-MS was performed to analyze the composition of SiNiSan decoction and SiNiSan-medicated serum (SMS). In addition, western blots were done to analyze the representative protein expression in Wnt/β-catenin signaling. Immunofluorescence staining was done to analyze the protein levels in WB-F344 cells. Finally, in an attempt to measure the influence of SiNiSan on liver regeneration in rats, we constructed a rats partial hepatectomy models.

RESULTS

We demonstrated that SiNiSan treatment mitigated liver damage in mice, as evidenced by the decrease in serum AST and ALT levels, as well as improved liver tissue morphology. HPLC-MS results showed that SMS contained a variety of components from the SiNiSan decoction. Next, our results showed that SMS reduced the expression of α-fetoprotein (AFP) and enhanced the expression of albumin (ALB) and cytokeratin 19 (CK19) in WB-F344 cells. Further, SMS treatment induced the accumulation of β-catenin. After 14 days of SMS treatment, β-catenin protein underwent nuclear translocation and bound to the LEF1 receptor in the nucleus, which regulated c-Myc and Cyclin D1 factors to activate Wnt/β-catenin signaling and promoted differentiation of WB-F344 cells. In addition, we demonstrated that SiNiSan increased liver regeneration in rat hepatectomy.

CONCLUSION

Collectively, the current study revealed that SiNiSan alleviated the acute liver injury induced by CCl4 as well as the chronic liver damage triggered by alcohol and sucrose in vitro. Concurrently, SMS treatment induced hepatic stem cell differentiation by activating Wnt/β-catenin signaling in vivo. Further study showed that SiNiSan promoted the regeneration of rats liver. The current study provides a theoretical basis for the clinical treatment of liver-related diseases with SiNiSan.

Effect of Arthrospira powders from different producers on the formation of endothelial cell monolayers

Arthrospira platensis (AP) and some of its derived products have well-established biological activities as antioxidants or as agents to reduce cardiovascular disease risk factors. Furthermore, AP products have gained increasing importance as potential anti-cancer agents. However, the ingredients of the available products vary greatly with the origin, the type of production and processing, which could have significant consequences for their biological effects. Therefore, the composition and biological influence of five distinct AP powders, which were acquired commercially or produced at a public biotechnology institute, were investigated in regard to their endothelialization capacity using a cell impedance- (CI) based measurement method. The study revealed that the AP composition and especially the influence on HUVEC proliferation differed significantly between the five AP powders up to 109%.Thus, it could be shown that the method used allows the reliable detection of quantitative differences in biological effects of different AP preparations.

Effect of δ-Tocopherol on Mice Adipose Tissues and Mice Adipocytes Induced Inflammation

The study aim was to evaluate the potential anti-inflammatory effects of vitamin E analogs, especially α-tocopherol and δ-tocopherol. We used male C57BL/6JJcl mice, which were divided into four groups: the control (C), high-fat and high-sucrose diet (H), high-fat and high-sucrose diet+α-tocopherol (Ha) and high-fat and high-sucrose diet+δ-tocopherol (Hd) groups. The mice were fed for 16 weeks. To the high-fat and high-sucrose diet, 800 mg/kg of α-tocopherol or δ-tocopherol was added more. The final body weight was significantly higher in the H group than in the C group. On the other hand, the final body weight was drastically lower in the Ha group and Hd group than in the H group. However, the energy intake was not significantly different among all groups. Therefore, we assumed that α-tocopherol and δ-tocopherol have potential anti-obesity effect. Besides, inflammatory cytokine gene expression was significantly higher in the epididymal fat of the H group than in the C group. These results showed that inflammation was induced by epididymal fat of mice fed a high-fat and high-sucrose diet for 16 weeks. Unfortunately, addition of α-tocopherol or δ-tocopherol to the diet did not restrain inflammation of epididymal fat. Investigation of the anti-inflammatory effects of α-tocopherol or δ-tocopherol in co-cultured 3T3-L1 cells and RAW264.7 cells showed that δ-tocopherol inhibited increased gene expression of the inflammatory cytokines, IL-1β, IL-6, and iNOS. These results suggest that an anti-inflammatory effect in the δ-tocopherol is stronger than that in the α-tocopherol in vitro. We intend to perform an experiment by in vivo sequentially in the future.

Spirulina platensis Inclusion Reverses Circulating Pro-inflammatory (Chemo)cytokine Profiles in Broilers Fed Low-Protein Diets

Proteins are considered the most expensive nutrients in commercial modern broiler production, and their dietary inclusion at low levels is pivotal to minimize feed costs and reduce nitrogen waste. The quest for an environmentally friendly source of proteins that favor the formulation of low protein diets without compromising broiler health, welfare, and growth performance has become a hotspot in nutrition research. Due to its high protein content, the naturally growing Spirulina microalgae is considered a promising nutrient source. The purpose of the present study was, therefore, to determine the effects of Spirulina supplementation on liver bacterial translocation, hematological profile, and circulating inflammatory and redox markers in broilers fed a low-protein diet. One-day-old Ross 708 male broilers (n = 180) were randomly assigned into one of three experimental treatments: standard diet as a control, low protein diet, and low protein diet supplemented with 100 g/kg of Spirulina. Target molecular markers were measured in the peripheral blood circulation using real-time quantitative PCR. Reducing dietary proteins increased bacterial translocation and systemic inflammation as indicated by proportions of basophils among blood leukocytes. The expression levels of circulating pro-inflammatory cytokines [interleukin (IL)-3, IL-6, IL-4, IL-18, and tumor necrosis factor-α], chemokines (CCL-20), and NOD-like receptor family pyrin domain containing 3 inflammasome were significantly upregulated in birds fed the low protein diet compared with the control. The inclusion of Spirulina reversed these effects, which indicates that Spirulina reduces systemic inflammation- and bacterial translocation-induced by a low protein diet and could be a promising alternative protein source in poultry diets.

[Features of free radical processes in the liver of rats with a nutrient imbalance]

The activity of free radical processes in liver mitochondria was investigated in rats kept on high-sucrose and low protein/high-sucrose diets. Excess of dietary sucrose caused intensification of free radical processes in liver mitochondria as evidenced by increased hydroxyl radical generation, accumulation of primary (conjugated dienes, ketodienes) and secondary products (TBA-reactive products) of lipid peroxidation, increased cholesterol/phospholipids ratio and also accumulation of oxidative modification products of proteins (carbonyl derivatives). Additional nutritional protein deficiency (low protein/high-sucrose diet) enhanced destructive changes in liver mitochondria. This suggests a critical role of nutrient protein supplementation for maintaining the functional activity of mitochondria. The established changes can be considered as one of possible mechanisms of functional liver activity violation in conditions of nutrient imbalance.

Total Lipids Content, Lipid Class and Fatty Acid Composition of Ten Species of Microalgae

Microalgae is a potential producer of functional lipids such as n-3 polyunsaturated fatty acids (PUFA) and fucoxanthin. In the present study, lipids from ten microalgae species were analyzed especially focusing on the fucoxanthin, lipid and fatty acid compositions. The study revealed a remarkable variation in total lipids content, fucoxanthin content, lipid class composition and n-3 PUFA content in individual species, although they belong to the same genus. Among microalgae examined, Pavlova lutheri contained the highest total lipids content (313.59 mg g^-1 dry weight) and considerable amount of fucoxanthin (3.13 mg g^-1 dry weight). It also had the highest level (28.01%) of total n-3 PUFA with high level of eicosapentaenoic acid (EPA) (17.76%) and docosahexaenoic acid (DHA) (7.61%). The highest fucoxanthin content (5.19 mg g^-1 dry weight) was observed in Chaetoceros gracilis. C. gracilis also contained relatively high level of total lipids (228.87 mg g^-1 dry weight) and 10.67% EPA. The results also demonstrated that Nannochloropsis oculata contained the greatest amount of EPA (26.21%), while Isochrysis galbana had the highest level of DHA (8.76%). And both microalgae contained 1.71 and 4.44 mg g^-1 dry weight fucoxanthin, respectively. Microalgal lipids containing abundant fucoxanthin and n-3 PUFA such as EPA and DHA in the present study will be used as nutraceutical lipids with great commercial potential.

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.