Astaxanthin and improvement of dementia: A systematic review of current clinical trials

Worldwide, the incidence of neurodegenerative diseases especially dementia is steadily increasing due to the aging population. Abundant research emerges on the probability of combating or preventing the degeneration process, with the most established one being to tackle the existence of oxidative stress and free radicals production due to their nature of aggravating dementia. Astaxanthin, a marine carotenoid, was proven to be a protective agent of cerebral ischemia through many animal model clinical trials. This review summarizes the evidence of Astaxanthin's benefits for cognitive function across clinical trials done in older age. The results are of interest as its supplementation does not exhibit unwanted issues on the consumer based on physical and laboratory examinations. Despite not being supported statistically, however, subjective and objective cognitive amelioration were reported according to the majority of this review's trial subjects. Although there is no clear and direct mechanism for cognitive improvement by Astaxanthin activity in the body systems, the encouragement of Astaxanthin supplementation should be considered as the elderly with dementia may highly benefit from the improved cognitive function.

Health Benefits of Quercetin in Age-Related Diseases

Polyphenols are the known group of phytochemicals that essentially consists of phenolic rings. These are the plant product present in varied fruits and vegetables. These secondary metabolites perform a protective function in plants from environmental and biological stress. When consumed as a human diet these are also known to prevent various age-associated diseases. Polyphenols are known to possess antioxidant properties and protect against oxidative stress. The literature survey was carried out using databases such as PubMed, Science direct and Springer. The research articles from last 10–12 years were selected for this review based on its relevancy with the topic. The articles selected was mainly focused on quercetin and its health benefits. The present review highlights the main functions of a flavonoid, quercetin. Quercetin is among the widely occurring polyphenol, found abundantly in nature. It is commonly present in different plant products. Onion is known to have the highest quantity of quercetin. This plant compound is possessed antioxidant properties and is considered to have a protective function against aging. It is known to be present in both free and conjugated forms. Quercetin has anti-oxidative, anti-inflammatory, anti-proliferative, anti-carcinogenic, anti-diabetic, and anti-viral properties. The molecule is lipophilic and can easily cross the BBB (Blood-Brain Barrier) and hence protects from neurodegenerative diseases. Various in vivo and in vitro studies have demonstrated the role of quercetin and here a detailed review of quercetin as a curative agent in neurodegeneration, diabetes, cancer, and inflammation has been carried out. Studies have proved that quercetin plays a crucial role in the prevention of age-related disorders. Quercetin is a potent antioxidant which is currently being used in various pharmaceuticals. Properties of quercetin can be further explored in various other disorders. Nanoformulations and liposomal formulations of quercetin can be made to treat other age associated diseases.

Recent advances in the protective role of metallic nanoparticles in red blood cells

The interaction of nanoparticles with the biological system has increased with the increasing popularity of nanomedicines. Red blood cells (RBCs) are very sensitive, and abundant cells in the blood. They are highly prone to oxidative damage due to constant interaction with oxygen itself, foreign particles in the blood, and the lack of repair mechanism. The cell membrane of RBCs undergoes lipid peroxidation, protein oxidation, and heme degradation which results in altered membrane permeability, changes in the morphology, and functioning of RBCs. The nanoparticles induce oxidative stress, hemolysis, morphological changes, membrane deformability, and alterations in hemoglobin structure in RBCs. In this review, the effects of metallic nanoparticles and their modifications on the physiology, and life span of RBCs are discussed. The detailed analysis of the antioxidant enzymes-like activity of metal nanoparticles is expected to highlight the beneficial use of these metal nanoparticles in RBCs against oxidative stress and the development of new biosafe nanodrugs.

Quercetin Mitigates Red Blood Cell Membrane Bound Na+, K+-ATPase Transporter During Human Aging

Increasing interest has recently focused on determining whether quercetin may exert anti-aging properties or not? The objective of this study was determination of Na⁺, K⁺ -ATPase activity in quercetin-treated red blood cells during human aging. The study was carried out on human blood samples. The subjects were divided into different age groups, young, middle, and old. The effects of quercetin were evaluated by determining Na⁺, K⁺ -ATPase activity by co-incubating the red blood cells in presence of quercetin (10^-6 M to 10^-3 M final concentration). Quercetin causes 15% increase in Na⁺, K⁺ -ATPase activity at 10^-4 M and 17% at 10^-3 M as compared to the young control age group. The effect was insignificant at 10^-5 M (7%) and 10^-6 M (5%) in the young age group. Quercetin showed significant increase at 10^-6 M to 10^-3 M in Na⁺, K⁺ -ATPase activity as compared to the middle control age group. A significant increase in Na⁺, K⁺ -ATPase activity was observed at all concentrations [10^-6 M (31%), 10^-5 M (39%), 10^-4 M (51%), and 10^-3 M (61%)] in elderly population. We believe that these findings will help in further research against oxidative stress in red blood cells.

Red blood cells as an efficient in vitro model for evaluating the efficacy of metallic nanoparticles

Blood and the linings of blood vessels may be regarded as a fifth tissue type. The human body contains 5 × 10⁹ red blood cells (RBCs) per ml, a total of 2.5 × 10¹³ cells in the 5 l of blood present in the body. With an average lifetime of 125 days, human RBCs are destroyed by leukocytes in the spleen and liver. Nowadays red blood cells are extensively used to study various metabolic functions. Nanoparticles (NP) are being widely accepted for drug delivery system. This review summarizes the red blood cells, NPs and their characteristics on the basis of the RBC components along with drug delivery systems through RBCs. Further, we also discussed that how erythrocytes can be used as an efficient in vitro model for evaluating the efficacy of various nanocomposite materials.

Effects of Composite Supplement Containing Astaxanthin and Sesamin on Cognitive Functions in People with Mild Cognitive Impairment: A Randomized, Double-Blind, Placebo-Controlled Trial

Background:

Dementia and its first or transitional stage, mild cognitive impairment (MCI), is a major concern for the aging Japanese society. Thus, the use of dietary supplements to improve or maintain cognitive function has become a topic of public interest.

Objective:

In this study, we evaluated the effects of a composite supplement containing food-derived antioxidants, specifically astaxanthin and sesamin (AS), on cognitive function in people with MCI.

Method:

Twenty-one healthy participants with MCI were recruited in our double-blind placebo-controlled pilot study. They were assigned to either an AS group, who received ingestible capsules containing AS, or a placebo group, who received identical placebo capsules. To assess cognitive functions, we performed the Japanese version of the Central Nervous System Vital Signs (CNSVS) test and the Alzheimer’s Disease Assessment Scale-Cog test at baseline, after 6 weeks, and after 12 weeks of dietary supplementation.

Results:

The CNSVS test revealed significant improvements in psychomotor speed and processing speed in the AS group compared with the placebo group, suggesting that the daily supplementation of AS improved cognitive functions related to the ability to comprehend, and perform complex tasks quickly and accurately.

Conclusion:

Our results provide support for the use of AS as a dietary supplementation for improving cognitive functions.

Microarray Based Functional Analysis of Myricetin and Proteomic Study on Its Anti-Inflammatory Property

Myricetin has been reported as a promising chemopreventive compound with multiple biofunctions. To evaluate its influence on gene expressions in genome-wide set and further investigate its anti-inflammatory property, the present study performed Gene Ontology and Ingenuity Pathway Analysis (IPA) to describe the basic gene expression characteristics by myricetin treatment in HepG2 cells, confirmed its multi-biofunction by real-time fluorescent quantitative PCR (RT-qPCR), and further verified its anti-inflammatory property by Western blotting and bio-plex-based cytokines assay. The IPA data showed that 337 gene expressions (48% of the top molecules) are disturbed over 2-fold, and the most possible biofunctions of myricetin are the effect on “cardiovascular disease, metabolic disease, and lipid metabolism,” via regulation of 28 molecules with statistic score of 46. RT-qPCR data confirmed the accuracy of microarray data, and cytokines assay results indicated that 6 of the total 27 inflammatory cytokine secretions were significantly inhibited by myricetin pretreatment, including TNF-α, IFN-γ, IL-1α, IL-1β, IL-2, and IL-6. The present study is the first time to elucidate the multi-function of myricetin in genome-wide set by IPA analysis and verify its anti-inflammatory property by proteomics of cytokines assay. Therefore, these results enrich the comprehensive bioactivities of myricetin and reveal that myricetin has powerful anti-inflammatory property, which provides encouragement for in vivo studies to verify its possible health benefits.

Gold nanoparticle surface engineering strategies and their applications in biomedicine and diagnostics

Gold nanoparticles (AuNPs) have found a wide range of biomedical and environmental monitoring applications (viz. drug delivery, diagnostics, biosensing, bio-imaging, theranostics, and hazardous chemical sensing) due to their excellent optoelectronic and enhanced physico-chemical properties. The modulation of these properties is done by functionalizing them with the synthesized AuNPs with polymers, surfactants, ligands, drugs, proteins, peptides, or oligonucleotides for attaining the target specificity, selectivity and sensitivity for their various applications in diagnostics, prognostics, and therapeutics. This review intends to highlight the contribution of such AuNPs in state-of-the-art ventures of diverse biomedical applications. Therefore, a brief discussion on the synthesis of AuNPs has been summarized prior to comprehensive detailing of their surface modification strategies and the applications. Here in, we have discussed various ways of AuNPs functionalization including thiol, phosphene, amine, polymer and silica mediated passivation strategies. Thereafter, the implications of these passivated AuNPs in sensing, surface-enhanced Raman spectroscopy (SERS), bioimaging, drug delivery, and theranostics have been extensively discussed with the a number of illustrations.

Gold nanoparticle surface engineering strategies and their applications in biomedicine and diagnostics

Gold nanoparticles (AuNPs) have found a wide range of biomedical and environmental monitoring applications (viz. drug delivery, diagnostics, biosensing, bio-imaging, theranostics, and hazardous chemical sensing) due to their excellent optoelectronic and enhanced physico-chemical properties. The modulation of these properties is done by functionalizing them with the synthesized AuNPs with polymers, surfactants, ligands, drugs, proteins, peptides, or oligonucleotides for attaining the target specificity, selectivity and sensitivity for their various applications in diagnostics, prognostics, and therapeutics. This review intends to highlight the contribution of such AuNPs in state-of-the-art ventures of diverse biomedical applications. Therefore, a brief discussion on the synthesis of AuNPs has been summarized prior to comprehensive detailing of their surface modification strategies and the applications. Here in, we have discussed various ways of AuNPs functionalization including thiol, phosphene, amine, polymer and silica mediated passivation strategies. Thereafter, the implications of these passivated AuNPs in sensing, surface-enhanced Raman spectroscopy (SERS), bioimaging, drug delivery, and theranostics have been extensively discussed with the a number of illustrations.

Spectroscopic determination of intracellular quercetin uptake using erythrocyte model and its implications in human aging

The present study was carried out to detect intracellular quercetin uptake by RBCs during human aging. The study was carried out on 95 normal healthy subjects of both the sexes. Intracellular quercetin uptake was estimated by performing ethyl acetate extraction. A significant (p < 0.001) decline in intracellular quercetin uptake by human RBCs was observed in elderly as compared to young population, while plasma membrane redox system (PMRS) activity was significantly decreasing as a function of human age. To the best of our knowledge, we are the first to present quercetin uptake by erythrocytes during aging in humans with this study. It is hypothesized that intracellular uptake of quercetin may serve as an intracellular electron donor for plasma membrane redox system in red blood cells during cellular aging which plays an important role in extracellular dehydroascorbate reduction and ascorbate recycling.

The Protective Role of Astaxanthin for UV-Induced Skin Deterioration in Healthy People-A Randomized, Double-Blind, Placebo-Controlled Trial

Skin is a major safeguard tissue in humans. Because biological barrier function is deteriorated by several kinds of stresses including exposure to ultra-violet (UV) rays, the protection and treatment of skin conditions by dietary supplements are important. We therefore evaluated the effects of dietary supplementation with an algal food-derived antioxidant, astaxanthin, on UV-induced skin deterioration. Twenty-three healthy Japanese participants were recruited to a 10-week double-blind placebo-controlled study. They were assigned to the astaxanthin group supplemented with a capsule containing 4 mg of astaxanthin or the placebo group. To assess the protective role of astaxanthin for UV-induced skin deterioration, we determined the minimal erythema dose (MED) and analyzed UV-induced changes of moisture and transepidermal water loss (TEWL) at baseline and after 9 weeks of supplementation. Subjective skin conditions were assessed by the visual analog scale. The astaxanthin group showed increased MED compared with placebo. In addition, the astaxanthin group had a reduced loss of skin moisture in the irradiated area compared with placebo. Subjective skin conditions for “improvement of rough skin” and “texture” in non-irradiated areas were significantly improved by astaxanthin. Astaxanthin seems protective against UV-induced skin deterioration and helps maintain healthy skin in healthy people.

Phytofabricated metallic nanoparticles and their clinical applications

Metallic nanoparticles (MNPs) have seen myriad applications in various fields of science and technology.