The effects of spirulina intake on clinical and metabolic parameters in Alzheimer's disease: A randomized, double-blind, controlled trial

The role of algae, fungi, and insect-derived proteins and bioactive peptides in preventive and clinical nutrition

The current global trend in the nutrition, epidemiologic and demographic transitions collectively alarms the need to pursue a sustainable protein diet that respects ecosystem and biodiversity from alternative sources, such as algae, fungi and edible insects. Then, changing the nutrition reality is extremely important to impede the global syndemic of obesity, undernutrition and climate change. This review aims to synthesize the published literature on the potential roles of alternative proteins and their derived bioactive peptides in preventive and clinical nutrition, identify research gaps and inform future research areas. Google Scholar and PubMed databases from their inception up to 30 June 2024 were searched using keywords to access pertinent articles published in English language for the review. Overall, proteins derived from algae, fungi, and edible insects are high-quality proteins as animal sources and demonstrate significant potential as a sustainable source of bioactive peptides, which are metabolically potent and have negligible adverse effects. They show promise to prevent and treat diseases associated with oxidative stress, obesity, diabetes, cancer, cardiovascular disease (especially hypertension), and neurodegenerative diseases. Given the abundance of algae, fungi and insect peptides performed in vitro or in vivo animals, further clinical studies are needed to fully establish their safety, efficacy and practical application in preventive and clinical nutrition. Additionally, social and behavioral change communication strategies would be important to increase health awareness of nutritional benefits and promote consumer acceptance of alternative protein sources.

Comprehensive Review of the Latest Investigations of the Health-Enhancing Effects of Selected Properties of Arthrospira and Spirulina Microalgae on Skin

Arthospira platensis and Spirulina platensis microalgae are a rich source of pro-health metabolites (% d.m.): proteins (50.0-71.3/46.0-63.0), carbohydrates (16.0-20.0/12.0-17.0), fats (0.9-14.2/6.4-14.3), polyphenolic compounds and phenols (7.3-33.2/7.8-44.5 and 4.2/0.3 mg GAE/g), and flavonoids (1.9/0.2 QUE/g) used in pharmaceutical and cosmetic formulations. This review summarises the research on the chemical profile, therapeutic effects in dermatological problems, application of Arthrospira and Spirulina microalgae, and contraindications to their use. The pro-health properties of these microalgae were analysed based on the relevant literature from 2019 to 2024. The antiviral mechanism of microalgal activity involves the inhibition of viral replication and enhancement of immunity. The anti-acne activity is attributed to alkaloids, alkanes, phenols, alkenes, phycocyanins, phthalates, tannins, carboxylic and phthalic acids, saponins, and steroids. The antibacterial activity generally depends on the components and structure of the bacterial cell wall. Their healing effect results from the inhibition of inflammatory and apoptotic processes, reduction of pro-inflammatory cytokines, stimulation of angiogenesis, and proliferation of fibroblasts and keratinocytes. The photoprotective action is regulated by amino acids, phlorotannins, carotenoids, mycosporins, and polyphenols inhibiting the production of tyrosinase, pro-inflammatory cytokines, and free oxygen radicals in fibroblasts and the stimulation of collagen production. Microalgae are promising molecular ingredients in innovative formulations of parapharmaceuticals and cosmetics used in the prophylaxis and therapy of dermatological problems. This review shows the application of spirulina-based commercial skin-care products as well as the safety and contraindications of spirulina use. Furthermore, the main directions for future studies of the pro-health suitability of microalgae exerting multidirectional effects on human skin are presented.

Shedding light on the impacts of Spirulina platensis on gut microbiota and related health benefits

Spirulina (S.) platensis is a blue-green algae with reported nutritional and health-promoting properties, such as immunomodulating, antioxidant, cholesterol-lowering properties, and beneficial effects on inflammatory diseases. Spirulina platensis can improve the function and composition of the gut microbiota and exert systemic beneficial effects. Gut dysbiosis is characterized by an imbalance in the composition and function of gut microbiota and is associated with several diseases. Some dietary bioactive compounds can restore the composition, diversity, and function of the gut microbiota and improve health-related parameters. This review proposes to gather relevant information on the effects of S. platensis supplementation on the modulation of the function and composition of gut microbiota and local and systemic measures related to gut health, such as inflammation, oxidative stress, and glucose and lipid metabolism. The body of evidence conducted with animals and clinical studies shows that S. platensis supplementation increased gut microbiota diversity and improved gut microbiota composition, as reported by a decrease in the Firmicutes/Bacteroides ratio, increase in the relative abundance of Prevotella and Lactobacillaceae, increase in short-chain fatty acid production and decrease of gut permeability. Improvements in gut microbiota have been associated with host health benefits such as anti-obesity, anti-diabetic, anti-hypertensive, anti-lipemic, anti-inflammatory, and antioxidant effects.

Potential Role of Oxidative Stress in the Pathophysiology of Neurodegenerative Disorders

Neurodegeneration causes premature death in the peripheral and central nervous system. Neurodegeneration leads to the accumulation of oxidative stress, inflammatory responses, and the generation of free radicals responsible for nervous disorders like amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and Huntington's disorders. Therefore, focus must be diverted towards treating and managing these disorders, as it is very challenging. Furthermore, effective therapies are also lacking, so the growing interest of the global market must be inclined towards developing newer therapeutic approaches that can intercept the progression of neurodegeneration. Emerging evidences of research findings suggest that antioxidant therapy has significant potential in modulating disease phenotypes. This makes them promising candidates for further investigation. This review focuses on the role of oxidative stress and reactive oxygen species in the pathological mechanisms of various neurodegenerative diseases, amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and Huntington's disorders and their neuroprotection. Additionally, it highlights the potential of antioxidant-based therapeutics in mitigating disease severity in humans and improving patient compliance. Ongoing extensive global research further sheds light on exploring new therapeutic targets for a deeper understanding of disease mechanisms in the field of medicine and biology targeting neurogenerative disorders.

Potential Protective Effects of Spirulina (Spirulina platensis) against In Vitro Toxicity Induced by Heavy Metals (Cadmium, Mercury, and Lead) on SH-SY5Y Neuroblastoma Cells

Spirulina, a filamentous microalga, is used all over the world as a nutraceutical dietary supplement. Recent studies have focused on examining its chelating activity and antioxidant properties, especially as a candidate for protection against neurotoxicity caused by heavy metals. The MTT test and LDH assay were used to examine the viability of the SH-SY5Y cells for 24, 48, and 72 h, to Cd, Hg, and Pb, individually or in combination with Spirulina, and the effects of necrotic cell death. In comparison to the control group, the viability of SH-SY5Y cells decreased after 24 h of exposure, with Cd being more toxic than Hg and Pb being less lethal. The effects of heavy metal toxicity on cell survival were ranked in order after 72 h under identical experimental circumstances as follows: Hg, Pb, and Cd. The viability of the cells was then tested after being exposed to Spirulina at doses of 5 at 50 (%v/v) for 24, 48, and 72 h, respectively. SH-SY5Y cells that had been treated with mixtures of heavy metals and Spirulina underwent the same assay. Cell viability is considerably increased by using Spirulina treatments at the prescribed periods and doses. Instead, the same procedure, when applied to SH-SY5Y cells, caused the release of LDH, which is consistent with the reduction in cell viability. We demonstrated for the first time, considering all the available data, that Spirulina 5, 25, and 50 (%v/v) enhanced the number of viable SH-SY5Y cells utilized as a model system for brain cells. Overall, the data from the present study provide a first insight into the promising positive role of Spirulina against the potentially toxic effects of metals.

Stalling the Course of Neurodegenerative Diseases: Could Cyanobacteria Constitute a New Approach toward Therapy?

Neurodegenerative diseases (NDs) are characterized by progressive and irreversible neuronal loss, accompanied by a range of pathological pathways, including aberrant protein aggregation, altered energy metabolism, excitotoxicity, inflammation, and oxidative stress. Some of the most common NDs include Alzheimer's Disease (AD), Parkinson's Disease (PD), Multiple Sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS), and Huntington's Disease (HD). There are currently no available cures; there are only therapeutic approaches that ameliorate the progression of symptoms, which makes the search for new drugs and therapeutic targets a constant battle. Cyanobacteria are ancient prokaryotic oxygenic phototrophs whose long evolutionary history has resulted in the production of a plethora of biomedically relevant compounds with anti-inflammatory, antioxidant, immunomodulatory, and neuroprotective properties, that can be valuable in this field. This review summarizes the major NDs and their pathophysiology, with a focus on the anti-neurodegenerative properties of cyanobacterial compounds and their main effects.