A comprehensive review on therapeutic potentials of photobiomodulation for neurodegenerative disorders.

A series of experimental trials over the past two centuries has put forth Photobiomodulation (PBM) as a treatment modality that utilizes colored lights for various conditions. While in its cradle, PBM was used for treating simple conditions such as burns and wounds, advancements in recent years have extended the use of PBM for treating complex neurodegenerative diseases (NDDs). PBM has exhibited the potential to curb several symptoms and signs associated with NDDs. While several of the currently used therapeutics cause adverse side effects alongside being highly invasive, PBM on the contrary, seems to be broad-acting, less toxic, and non-invasive. Despite being projected as an ideal therapeutic for NDDs, PBM still isn't considered a mainstream treatment modality due to some of the challenges and knowledge gaps associated with it. Here, we review the advantages of PBM summarized above with an emphasis on the common mechanisms that underlie major NDDs and how PBM helps tackle them. We also discuss important questions such as whether PBM should be considered a mainstay treatment modality for these conditions and if PBM's properties can be harnessed to develop prophylactic therapies for high-risk individuals and also highlight important animal studies that underscore the importance of PBM and the challenges associated with it. Overall, this review is intended to bring the major advances made in the field to the spotlight alongside addressing the practicalities and caveats to develop PBM as a major therapeutic for NDDs.

An overview of systematic reviews of acupuncture for neurodegenerative disease.

BACKGROUND: Acupuncture has been widely used in the treatment of neurodegenerative diseases and a large number of systematic reviews (SRs) have been published, but the results are controversial. Therefore, it is necessary to comprehensively summarize and objectively evaluate the clinical evidence of acupuncture for neurodegenerative diseases. OBJECTIVE: To evaluate the SRs that assess the efficacy and safety of acupuncture for neurodegenerative diseases. This overview is intended to provide evidence for clinical decision making by healthcare providers and policymakers and to provide evidence for clinical decision making by healthcare providers and policymakers and to provide recommendations for researchers to conduct high quality SRs and clinical studies. METHODS: We searched four Chinese databases (SinoMed, CNKI, Wanfang and VIP) and four international databases (Cochrane Library, Embase, PubMed and Web of Science) for SRs of acupuncture for neurodegenerative diseases. The search period ran from the beginning of the database to March 5, 2023. Literature screening and data extraction were performed independently by two individuals. Methodological quality, risk of bias and associated evidence levels were assessed for all SRs using AMSTER 2, ROBIS and GRADE tools. In addition, the RCT overlap between SRs was calculated by corrected coverage area (CCA). We also conducted quantitative synthesis or descriptive analysis of the relevant data. RESULTS: Finally, we identified 53 SRs (three were qualitative descriptions and fifty were meta-analyses). Under AMSTAR 2, only one SR was rated as moderate quality, six SRs as low quality and 46 SRs as very low quality. According to ROBIS, 33 SRs were rated as a high risk of bias and 20 as a low risk of bias. Cognitive functions in neurodegenerative diseases, activities of daily living and the motor and non-motor outcomes associated with PD were included to summary description. The pooled results show that acupuncture combined with conventional treatment may have an overall advantage over conventional treatment, but the quality of evidence is low. Specific adverse reactions/events were reported in 20 SRs. Common needle-related adverse events included pain, dizziness, bleeding, or subcutaneous hematoma. No severe adverse events were reported in any SRs. CONCLUSION: Evidence suggests that acupuncture is generally effective and relatively safe for cognitive function and activities of daily living in neurodegenerative diseases. In addition, acupuncture may have some benefits in improving motor and non-motor symptoms in patients with PD. However, high-quality RCTs and SRs are still needed to further clarify the efficacy and safety of acupuncture in treating neurodegenerative diseases.

Neurodegenerative Diseases: Can Caffeine Be a Powerful Ally to Weaken Neuroinflammation?

In recent years, there has been considerable research showing that coffee consumption seems to be beneficial to human health, as it contains a mixture of different bioactive compounds such as chlorogenic acids, caffeic acid, alkaloids, diterpenes and polyphenols. Neurodegenerative diseases (NDs) are debilitating, and non-curable diseases associated with impaired central, peripheral and muscle nervous systems. Several studies demonstrate that neuroinflammation mediated by glial cells-such as microglia and astrocytes-is a critical factor contributing to neurodegeneration that causes the dysfunction of brain homeostasis, resulting in a progressive loss of structure, function, and number of neuronal cells. This happens over time and leads to brain damage and physical impairment. The most known chronic NDs are represented by Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD). According to epidemiological studies, regular coffee consumption is associated with a lower risk of neurodegenerative diseases. In this review, we summarize the latest research about the potential effects of caffeine in neurodegenerative disorders prevention and discuss the role of controlled caffeine delivery systems in maintaining high plasma caffeine concentrations for an extended time.

[A new paradigm for the development of neurodegenerative diseases on the example of Alzheimer's disease and Parkinson's disease.]

The role of neuronal inflammation developing during the formation of amyloid plaques and Lewy bodies has been investigated. The influence of various exogenous and endogenous factors on the development of neuroinflammation has been established, but the role of various infectious agents in the development of this process has been much less studied. Today, the existence of a universal trigger mechanism of the neurodegenerative process is obvious: a specific pathogen of a bacterial or viral nature (including a long-term persistent in the nervous tissue in a latent state), reactivating, penetrates into certain cerebral structures, where it is influenced by either Aß or resident macrophages of the central nervous system, which, in turn, are activated and induce the release of pro-inflammatory cytokines, leading to the development of neuronal inflammation, autophagy and neurodegeneration. Reactivation of latent, such as herpes, infection in individuals who are carriers of APOE4 significantly increases the risk of developing Alzheimer's disease. Class II genes of the HLA locus (HLA II) may be related to the progression of neurodegenerative diseases. The increase in iron levels in the glia is induced by inflammation, which leads to neurodegeneration. Disruption of the homeostasis of redox-active metals, iron and copper, is an integral part of the pathogenesis of Alzheimer's disease and Parkinson's disease. The developing neuroinflammation leads to the intensification of the processes of peroxidation, oxidation of metals and the development of ferroptosis.

The possible alleviating effect of garlic supplement on the neural retina in a rat model of hypercholesterolemia: a histological and immunohistochemical study.

The purpose of this work was to prove that oxidative stress is the main mechanism responsible for retinal neurodegenerative changes, subsequent apoptosis, and inflammatory cytokine release in rats fed with a high cholesterol diet (HCD) and determine the role of garlic in alleviating these changes. Forty rats were equally divided into four groups: control, garlic-treated (positive control), HCD, and HCD + garlic-treated (HCD + G). By the end of the experiment (24 weeks) blood samples were collected for assessment of serum lipid profile, oxidative stress parameters, and plasma levels of IL-6 and TNF-α. Both eyes of the rats were enucleated; one was used for light microscopic examination and the other for electron microscopic examination. There was a significant increase in the levels of serum lipids, oxidative stress parameters, IL-6 and TNF-α, and area of expression of caspase-3 in the HCD group compared to both the control and HCD + G groups. Histological examination revealed degenerative changes in all layers of the neural retina in the HCD group. Garlic administration resulted in a significant improvement in the biochemical, immunohistochemical, and histological characteristics of hypercholesterolemic rats. These findings support the hypotheses that garlic has strong antioxidant, anti-apoptotic, and anti-inflammatory properties. Garlic ameliorates the neurodegenerative changes in the neural retina of hypercholesteremic rats.

Unusual Bioactive Compounds with Antioxidant Properties in Adjuvant Therapy Supporting Cognition Impairment in Age-Related Neurodegenerative Disorders.

Cognitive function decline is strictly related to age, resulting in the loss of the ability to perform daily behaviors and is a fundamental clinical neurodegeneration symptom. It has been proven that an adequate diet, comprehensive nutrition, and a healthy lifestyle may significantly inhibit neurodegenerative processes, improving cognitive functions. Therefore, intensive research has been conducted on cognitive-enhancing treatment for many years, especially with substances of natural origin. There are several intervention programs aimed at improving cognitive functions in elderly adults. Cognitive functions depend on body weight, food consumed daily, the quality of the intestinal microflora, and the supplements used. The effectiveness in the prevention of dementia is particularly high before the onset of the first symptoms. The impact of diet and nutrition on age-associated cognitive decline is becoming a growing field as a vital factor that may be easily modified, and the effects may be observed on an ongoing basis. The paper presents a review of the latest preclinical and clinical studies on the influence of natural antioxidants on cognitive functions, with particular emphasis on neurodegenerative diseases. Nevertheless, despite the promising research results in animal models, the clinical application of natural compounds will only be possible after solving a few challenges.

Copper, Iron, Selenium and Lipo-Glycemic Dysmetabolism in Alzheimer's Disease.

The aim of the present review is to discuss traditional hypotheses on the etiopathogenesis of Alzheimer's disease (AD), as well as the role of metabolic-syndrome-related mechanisms in AD development with a special focus on advanced glycation end-products (AGEs) and their role in metal-induced neurodegeneration in AD. Persistent hyperglycemia along with oxidative stress results in increased protein glycation and formation of AGEs. The latter were shown to possess a wide spectrum of neurotoxic effects including increased Aß generation and aggregation. In addition, AGE binding to receptor for AGE (RAGE) induces a variety of pathways contributing to neuroinflammation. The existing data also demonstrate that AGE toxicity seems to mediate the involvement of copper (Cu) and potentially other metals in AD pathogenesis. Specifically, Cu promotes AGE formation, AGE-Aß cross-linking and up-regulation of RAGE expression. Moreover, Aß glycation was shown to increase prooxidant effects of Cu through Fenton chemistry. Given the role of AGE and RAGE, as well as metal toxicity in AD pathogenesis, it is proposed that metal chelation and/or incretins may slow down oxidative damage. In addition, selenium (Se) compounds seem to attenuate the intracellular toxicity of the deranged tau and Aß, as well as inhibiting AGE accumulation and metal-induced neurotoxicity.

Trichoderma reesei fungal degradation boosted the potentiality of date pit extract in fighting scopolamine-induced neurotoxicity in male rats.

Date pits are nutritious by-products, containing high levels of indigestible carbohydrates and polyphenols. To maximize the biological effects of the active ingredients, the hard shell of the polysaccharide must be degraded. Therefore, the current study aimed to assess the protective potentials of date pits extract (DP) and fungal degraded date pits extract (FDDP) against scopolamine (SCO)-induced neurodegeneration in male rats. Date pits were subjected to fungal degradation and extraction, followed by the measurement of phytochemicals and free radical scavenging activities. Forty-two adult Sprague-Dawley male rats were divided into seven groups: three control groups administered with either saline, DP or FDDP; four groups with neurodegeneration receiving SCO (ip 2 mg/kg/day, SCO group) with no treatment, SCO with DP (oral 100 mg/kg/day, DP + SCO group), SCO with FDDP (oral, 100 mg/kg/day, FDDP + SCO group), and SCO with donepezil (DON, oral, 2.25 mg/kg/day, DON + SCO group). The treatment duration was 28 days, and in the last 14 days, SCO was administered daily. Morris water maze test, acetylcholine esterase activity, oxidative stress, markers of inflammation and amyloidogenesis, and brain histopathology were assessed.

A State of the Art of Antioxidant Properties of Curcuminoids in Neurodegenerative Diseases.

Neurodegenerative diseases represent a set of pathologies characterized by an irreversible and progressive, and a loss of neuronal cells in specific areas of the brain. Oxidative phosphorylation is a source of energy production by which many cells, such as the neuronal cells, meet their energy needs. Dysregulations of oxidative phosphorylation induce oxidative stress, which plays a key role in the onset of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). To date, for most neurodegenerative diseases, there are no resolute treatments, but only interventions capable of alleviating the symptoms or slowing the course of the disease. Therefore, effective neuroprotection strategies are needed. In recent years, natural products, such as curcuminoids, have been intensively explored and studied for their therapeutic potentials in several neurodegenerative diseases. Curcuminoids are, nutraceutical compouns, that owen several therapeutic properties such as anti-oxidant, anti-inflammatory and neuroprotective effects. In this context, the aim of this review was to provide an overview of preclinical and clinical evidence aimed to illustrate the antioxidant effects of curcuminoids in neurodegenerative diseases. Promising results from preclinical studies encourage the use of curcuminoids for neurodegeneration prevention and treatment.

Polyphenols and Fish Oils for Improving Metabolic Health: A Revision of the Recent Evidence for Their Combined Nutraceutical Effects.

Polyphenols and omega-3 polyunsaturated fatty acids from fish oils, i.e., eicosapentaenoic and docosahexaenoic acids, are well-recognized nutraceuticals, and their single antioxidant and anti-inflammatory properties have been demonstrated in several studies found in the literature. It has been reported that the combination of these nutraceuticals can lead to three-fold increases in glutathione peroxidase activity, two-fold increases in plasma antioxidant capacity, decreases of 50-100% in lipid peroxidation, protein carbonylation, and urinary 8-isoprotanes, as well as 50-200% attenuation of common inflammation biomarkers, among other effects, as compared to their individual capacities. Therefore, the adequate combination of those bioactive food compounds and their single properties should offer a powerful tool for the design of successfully nutritional interventions for the prevention and palliation of a plethora of human metabolic diseases, frequently diet-induced, whose etiology and progression are characterized by redox homeostasis disturbances and a low-grade of chronic inflammation. However, the certain mechanisms behind their biological activities, in vivo interaction (both between them and other food compounds), and their optimal doses and consumption are not well-known yet. Therefore, we review here the recent evidence accumulated during the last decade about the cooperative action between polyphenols and fish oils against diet-related metabolic alterations, focusing on the mechanisms and pathways described and the effects reported. The final objective is to provide useful information for strategies for personalized nutrition based on these nutraceuticals.

Dystrophic microglia are associated with neurodegenerative disease and not healthy aging in the human brain.

Loss of physiological microglial function may increase the propagation of neurodegenerative diseases. Cellular senescence is a hallmark of aging; thus, we hypothesized age could be a cause of dystrophic microglia. Stereological counts were performed for total microglia, 2 microglia morphologies (hypertrophic and dystrophic) across the human lifespan. An age-associated increase in the number of dystrophic microglia was found in the hippocampus and frontal cortex. However, the increase in dystrophic microglia was proportional to the age-related increase in the total number of microglia. Thus, aging alone does not explain the presence of dystrophic microglia. We next tested if dystrophic microglia could be a disease-associated microglia morphology. Compared with controls, the number of dystrophic microglia was greater in cases with either Alzheimer's disease, dementia with Lewy bodies, or limbic-predominant age-related TDP-43 encephalopathy. These results demonstrate that microglia dystrophy, and not hypertrophic microglia, are the disease-associated microglia morphology. Finally, we found strong evidence for iron homeostasis changes in dystrophic microglia, providing a possible molecular mechanism driving the degeneration of microglia in neurodegenerative disease.

COVID-19 in age-related neurodegenerative diseases: is there a role for vitamin D3 as a possible therapeutic strategy?

The coronavirus disease (COVID-19), identified in Wuhan, China, on December 2019, was declared a pandemic by the World Health Organization, on March, 2020. Since then, efforts have been gathered to describe its clinical course and to determine preventive measures and treatment strategies. Adults older than 65 years of age are more susceptible to serious clinical symptoms and present higher mortality rates. Angiotensin-converting enzyme 2 (ACE2) is a major receptor for some coronavirus infection, including SARS-COV-2, but is also a crucial determinant in anti-inflammation processes during the renin-angiotensin system (RAS) functioning - converting angiotensin II to angiotensin 1-7. The decline in ACE2 expression that occurs with aging has been associated to the higher morbidity and mortality rates in older adults. These observations highlight the importance of investigating the association between COVID-19 and age-related neurodegenerative disorders, i.e., Parkinson's and Alzheimer's diseases. A possible option to reduce the risk of COVID-19 is vitamin D supplementation, due to its anti-inflammatory and immune-system-modulating effects. It has also been suggested that vitamin D supplementation plays a role in slowing progression of Parkinson and Alzheimer. The present study is a literature review of articles published on the theme COVID-19, Parkinson and Alzheimer's diseases, and the role played by vitamin D. PUBMED, MEDLINE, and EMBASE databases were consulted. Results confirm neurodegenerative and neuroinflammatory effects of COVID-19, aggravated in Parkinson's and Alzheimer's patients, and the important role of vitamin D as a possible therapeutic strategy. Nevertheless, randomized controlled trials and large population studies are still warranted.

Medicinal plants for diabetes associated neurodegenerative diseases: A systematic review of preclinical studies.

Diabetes mellitus is a metabolic defect with many complications for the patients. Deaths due to diabetes and its complications are increasing, and one of the most serious consequences are the neurological disorders. Chemical treatments have irreversible side effect and therefore the aim of this study is to evaluate the medicinal plants used for treatment of cognitive impairments and neurodegenerative diseases associated with diabetes in 2004-2020 period. Electronic databases used were PubMed, Scopus and Cochrane library. The keywords used were "diabetes," "plant," "herb," "neurodegenerative," "neurodegeneration," "cognitive," "cognition," "Alzheimer," "dementia." The non-English articles, repetitive articles and review studies were excluded. From total of 3,590 results, 58 articles are included in the study. The results show that many chemical treatments considered for this disease simply control hyperglycemia, but cannot improve the complications of diabetes. Herbal medicine could be more effective due to the high antioxidant activity of some medicinal plants. Biologically active substances of medicinal plants can improve the neurological disorders caused by diabetes via several pathways. The most important pathway is related to antioxidant properties. Other pathways include antiinflammatory, anti-apoptotic, neurotoxicity inhibition, neuronal death, increasing the uptake of glucose by cells and improve neurotransmitters levels involved in learning and memory.

Cellular Consequences of Coenzyme Q10 Deficiency in Neurodegeneration of the Retina and Brain.

Coenzyme Q10 (CoQ10) is a ubiquitous cofactor in the body, operating in the inner mitochondrial membrane, where it plays a vital role in the generation of adenosine triphosphate (ATP) through the electron transport chain (ETC). In addition to this, CoQ10 serves as an antioxidant, protecting the cell from oxidative stress by reactive oxygen species (ROS) as well as maintaining a proton (H+) gradient across lysosome membranes to facilitate the breakdown of cellular waste products. Through the process of ageing, the body becomes deficient in CoQ10, resulting in several systemic manifestations. On a cellular level, one of the consequences of CoQ10 deficiency is apoptosis, which can be visualised in tissues of the central nervous system (CNS). Diseases affecting the retina and brain such as age-related macular degeneration (AMD), glaucoma, Alzheimer's disease (AD) and Parkinson's disease (PD) have shown defects in cellular biochemical reactions attributed to reduced levels of CoQ10. Through further research into the pathogenesis of such conditions, the effects of CoQ10 deficiency can be counteracted through supplementation, early detection and intervention.

Copper Dyshomeostasis in Neurodegenerative Diseases-Therapeutic Implications.

Copper is one of the most abundant basic transition metals in the human body. It takes part in oxygen metabolism, collagen synthesis, and skin pigmentation, maintaining the integrity of blood vessels, as well as in iron homeostasis, antioxidant defense, and neurotransmitter synthesis. It may also be involved in cell signaling and may participate in modulation of membrane receptor-ligand interactions, control of kinase and related phosphatase functions, as well as many cellular pathways. Its role is also important in controlling gene expression in the nucleus. In the nervous system in particular, copper is involved in myelination, and by modulating synaptic activity as well as excitotoxic cell death and signaling cascades induced by neurotrophic factors, copper is important for various neuronal functions. Current data suggest that both excess copper levels and copper deficiency can be harmful, and careful homeostatic control is important. This knowledge opens up an important new area for potential therapeutic interventions based on copper supplementation or removal in neurodegenerative diseases including Wilson's disease (WD), Menkes disease (MD), Alzheimer's disease (AD), Parkinson's disease (PD), and others. However, much remains to be discovered, in particular, how to regulate copper homeostasis to prevent neurodegeneration, when to chelate copper, and when to supplement it.

Electroacupuncture Improves Motor Symptoms of Parkinson's Disease and Promotes Neuronal Autophagy Activity in Mouse Brain.

Autophagic defects are a hallmark of neurodegenerative disorders, such as Parkinson's disorder (PD). Enhancing autophagy to remove impaired mitochondria and toxic protein aggregation is an essential component of PD treatment. In particular, activation of autophagy confers neuroprotection in cellular and preclinical models of neurodegenerative diseases. In this study, we investigated the therapeutic mechanisms of electroacupuncture (EA) treatment in mice with established PD and evaluated the relationship between EA, autophagy, and different neurons in the mouse brain. We report that EA improves PD motor symptoms in mice and enhances (1) autophagy initiation (increased Beclin 1), (2) autophagosome biogenesis (increased Atg5, Atg7, Atg9A, Atg12, Atg16L, Atg3, and LC3-II), (3) autophagy flux/substrate degradation (decreased p62), and (4) mitophagy (increased PINK1 and DJ-1) in neurons of the substantia nigra, striatum, hippocampus, and cortex (affected brain areas of PD, Huntington disease, and Alzheimer's disease). EA enhances autophagy initiation, autophagosome biogenesis, mitophagy, and autophagy flux/substrate degradation in certain brain areas. Our findings are the first to show that EA regulates neuronal autophagy and suggest that this convenient, inexpensive treatment has exciting therapeutic potential in neurodegenerative disorders.

Regulation of degenerative spheroids after injury.

Neuronal injury leads to rapid, programmed disintegration of axons distal to the site of lesion. Much like other forms of axon degeneration (e.g. developmental pruning, toxic insult from neurodegenerative disorder), Wallerian degeneration associated with injury is preceded by spheroid formation along axons. The mechanisms by which injury leads to formation of spheroids and whether these spheroids have a functional role in degeneration remain elusive. Here, using neonatal mouse primary sympathetic neurons, we investigate the roles of players previously implicated in the progression of Wallerian degeneration in injury-induced spheroid formation. We find that intra-axonal calcium flux is accompanied by actin-Rho dependent growth of calcium rich axonal spheroids that eventually rupture, releasing material to the extracellular space prior to catastrophic axon degeneration. Importantly, after injury, Sarm1-/- and DR6-/-, but not Wlds (excess NAD+) neurons, are capable of forming spheroids that eventually rupture, releasing their contents to the extracellular space to promote degeneration. Supplementation of exogenous NAD+ or expressing WLDs suppresses Rho-dependent spheroid formation and degeneration in response to injury. Moreover, injured or trophically deprived Sarm1-/- and DR6-/-, but not Wlds neurons, are resistant to degeneration induced by conditioned media collected from wild-type axons after spheroid rupture. Taken together, these findings place Rho-actin and NAD+ upstream of spheroid formation and may suggest that other mediators of degeneration, such as DR6 and SARM1, mediate post-spheroid rupture events that lead to catastrophic axon disassembly.

Molecular Targets from Traditional Medicines for Neuroprotection in Human Neurodegenerative Diseases.

Neurodegeneration is one of the greatest threats to global public health. Neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease are among the major causes of chronic neurological conditions in the elderly populations. Hence, neuroprotection is at the epicenter of the current 21st-century research agenda in biomedicine. Yet, novel molecular targets are limited and solely needed for neuroprotection. Marked person-to-person variations in outcomes require a deeper understanding of drug targets in neurology and clinical neurosciences. In this context, traditional medicines offer untapped potentials for discovery and translation of novel molecular targets to human neurodegenerative disease research and clinical neurology. This expert review offers a synthesis of the prospects and challenges of harnessing new molecular targets from traditional medicines, with a view to applications for neuroprotection in human neurodegenerative diseases.

Polyphenols as Caloric-Restriction Mimetics and Autophagy Inducers in Aging Research.

It has been thought that caloric restriction favors longevity and healthy aging where autophagy plays a vital role. However, autophagy decreases during aging and that can lead to the development of aging-associated diseases such as cancer, diabetes, neurodegeneration, etc. It was shown that autophagy can be induced by mechanical or chemical stress. In this regard, various pharmacological compounds were proposed, including natural polyphenols. Apart from the ability to induce autophagy, polyphenols, such as resveratrol, are capable of modulating the expression of pro- and anti-apoptotic factors, neutralizing free radical species, affecting mitochondrial functions, chelating redox-active transition metal ions, and preventing protein aggregation. Moreover, polyphenols have advantages compared to chemical inducers of autophagy due to their intrinsic natural bio-compatibility and safety. In this context, polyphenols can be considered as a potential therapeutic tool for healthy aging either as a part of a diet or as separate compounds (supplements). This review discusses the epigenetic aspect and the underlying molecular mechanism of polyphenols as an anti-aging remedy. In addition, the recent advances of studies on NAD-dependent deacetylase sirtuin-1 (SIRT1) regulation of autophagy, the role of senescence-associated secretory phenotype (SASP) in cells senescence and their regulation by polyphenols have been highlighted as well. Apart from that, the review also revised the latest information on how polyphenols can help to improve mitochondrial function and modulate apoptosis (programmed cell death).

Pentacyclic triterpenoid-rich fraction of the Hardy kiwi (Actinidia arguta) improves brain dysfunction in high fat diet-induced obese mice.

This study was performed to investigate the effect of the chloroform fraction from Actinidia arguta (CFAA) on cognitive dysfunction in a C57BL/6 mouse model fed a high-fat diet (HFD) for 12 weeks. The CFAA has the protective effect on high glucose-induced neurotoxicity in MC-IXC cell (neuroblastoma cell line). In a C57BL/6 mouse model fed a HFD for 12 weeks, the improved glucose tolerance and cognitive dysfunction were observed in a group ingesting CFAA. In the brain tissue analysis, the impaired cholinergic, antioxidant system and mitochondria functions were improved in the CFAA group. In addition, in a molecular biology study, it was observed that CFAA improves HFD-induced abnormal insulin signaling such as increase of IRS phosphorylation at serine residues and reduction of Akt phosphorylation caused by the increase of JNK phosphorylation and then inhibited apoptosis. In the UPLC Q-TOF/MS analysis, pentacyclic triterpenoids such as asiatic acid (AA), madecassic acid (MA) were identified in CFAA as main compounds. Therefore, these results propose that Actinidia arguta rich in pentacyclic triterpenoids may be effective as preventive matter a therapeutic strategy to improve neurodegenerative disease caused by HFD.