Study of Nutraceuticals and Phytochemicals for the Management of Alzheimer's Disease: A Review.

BACKGROUND: Alzheimer's disease (AD) affects several people worldwide and has devastating impacts on society with a limited number of approaches for its pharmacological treatment. The main causes of AD are not clear yet. However, the formation of senile plaques, neurofibrillary tangles, hyper-phosphorylation of tau protein, and disruption of redox homeostasis may cause AD. These causes have a positive correlation with oxidative stress, producing reactive ions, which are responsible for altering the physiological condition of the body. CONCLUSION: Ongoing research recommended the use of phytochemicals as acetylcholinesterase inhibitors to hinder the onset and progression of AD. The natural compound structures, including lignans, flavonoids, tannins, polyphenols, triterpenes, sterols, and alkaloids have anti-inflammatory, antioxidant, and anti-amyloidogenic properties. The purpose of this article is to provide a brief introduction to AD along with the use of natural compounds as new therapeutic approaches for its management.

Impact of Traditional Plants and their Secondary Metabolites in the Discovery of COVID-19 Treatment.

BACKGROUND: Coronavirus Disease-2019 belongs to the family of viruses which cause serious pneumonia along with fever, breathing issues and infection of lungs, and was first reported in China and later spread worldwide. OBJECTIVE: Several studies and clinical trials have been conducted to identify potential drugs and vaccines for Coronavirus Disease-2019. The present study listed natural secondary metabolites identified from plant sources with antiviral properties and could be a safer and tolerable treatment for Coronavirus Disease-2019. METHODS: A comprehensive search on the reported studies was conducted using different search engines such as Google Scholar, SciFinder, Sciencedirect, Medline PubMed, and Scopus for the collection of research articles based on plant-derived secondary metabolites, herbal extracts, and traditional medicine for coronavirus infections. RESULTS: Status of COVID-19 worldwide and information of important molecular targets involved in COVID- 19 are described, and through literature search, it is highlighted that numerous plant species and their extracts possess antiviral properties and are studied with respect to coronavirus treatments. Chemical information, plant source, test system type with a mechanism of action for each secondary metabolite are also mentioned in this review paper. CONCLUSION: The present review has listed plants that have presented antiviral potential in the previous coronavirus pandemics and their secondary metabolites, which could be significant for the development of novel and a safer drug which could prevent and cure coronavirus infection worldwide.

Natural Products: A Rich Source of Antiviral Drug Lead Candidates for the Management of COVID-19.

Today, the world is suffering from the pandemic of a novel coronavirus disease (COVID-19), a respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This pandemic is the third fatal coronavirus outbreak that has already occurred in the 21st century. Even six months after its emergence, hundreds of thousands of people are still being infected with SARS-CoV-2, and thousands of lives are lost every day across the world. No effective therapy has been approved to date for the treatment of this disease, suggesting the need to broaden the scope in the search for effective treatments. Throughout history, folk medicine has been successfully used to treat various ailments in humans, and Traditional Chinese Medicine has been instrumental in the containment of a number of viral diseases. Owing to their high chemical diversity and safety profiles, natural products offer great promises as potentially effective antiviral drugs. In recent years, a large number of anti-coronaviral phytochemicals with different mechanisms of action have been identified. Among them, tetra-O-galloyl-ß-D-glucose, caffeic acid, and saikosaponin B2 block viral entry. A number of flavonoids inhibit viral proteases. Silvestrol inhibits protein synthesis. Myricetin and scutellarein inhibit viral replication. Emodin, luteolin, and quercetin demonstrate anti-coronaviral activity by inhibiting multiple processes in the virus life cycle. In this review, we critically evaluate the findings of the natural product-based anticoronaviral research that has been published during the last two decades, and attempt to provide a comprehensive description about their utility as potential broad-spectrum anti-coronaviral drugs, examining leads that may guide/facilitate anti-SARS-CoV-2 drug development studies.

COVID-19 Outbreak and Emerging Management through Pharmaceutical Therapeutic Strategy.

The latest SARS COV2 coronavirus contributes to a pandemic of millions of COVID-19. As there is no defensive immunity in humans and a virus can overcome inborn immune reaction, it can propagate unhindered, mostly in tissues contaminated. No unique therapies for COVID-19 contaminated patients are available at this time. The insights learned from previous respiratory viral infection control have given guidance into COVID- 19 therapy. Several complementary treatments have been tentatively introduced in hospital environments such as immune-modulators, antiviral, convalescent plasma transfusions and natural products. In COVID-19 patients, some of these therapies have provided substantial curative benefits. Moreover, numerous studies and clinical trials are being carried out in order to determine the efficacy of current pharmaceutical and natural products to establish possible therapeutic strategies for producing novel COVID-19 medicines. We summarized and defined the modes of mechanism, protection and efficacy on the existing therapeutic strategies for diseases linked to COVID-19 infection.

Cross-Interplay between Osmolytes and mTOR in Alzheimer's Disease Pathogenesis.

Alzheimer's disease, categorized by the piling of amyloid-ß (Aß), hyperphosphorylated tau, PHFs, NFTs and mTOR hyperactivity, is a neurodegenerative disorder, affecting people across the globe. Osmolytes are known for osmoprotectants and play a pivotal role in protein folding, function and protein stability, thus, preventing proteins aggregation, and counteracting effects of denaturing solutes on proteins. Osmolytes (viz., sorbitol, inositol, and betaine) perform a pivotal function of maintaining homeostasis during hyperosmotic stress. The selective advantage of utilising osmolytes over inorganic ions by cells is in maintaining cell volume without compromising cell function, which is important for organs such as the brain. Osmolytes have been documented not only as neuroprotectors but they also seem to act as neurodegenerators. Betaine, sucrose and trehalose supplementation has been seen to induce autophagy thereby inhibiting the accumulation of Aß. In contrast, sucrose has also been associated with mTOR hyperactivity, a hallmark of AD pathology. The neuroprotective action of taurine is revealed when taurine supplementation is seen to inhibit neural damage, apoptosis and oxidative damage. Inositol stereoisomers (viz., scyllo-inositol and myo-inositol) have also been seen to inhibit Aß production and plaque formation in the brain, inhibiting AD pathogenesis. However, TMAO affects the aging process adversely by deregulating the mTOR signalling pathway and then kindling cognitive dysfunction via degradation of chemical synapses and synaptic plasticity. Thus, it can be concluded that osmolytes may act as a probable therapeutic approach for neurodevelopmental disorders. Here, we have reviewed and focussed upon the impact of osmolytes on mTOR signalling pathway and thereby its role in AD pathogenesis.

A Computational Study of Natural Compounds from Bacopa monnieri in the Treatment of Alzheimer's Disease.

Keeping in view the public health-related issues of Alzheimer's disease (AD), its unpredictable occurrence and progression indicate the needs for best treatment options. The present bioinformatics study explores the binding pattern and molecular interactions between human acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes with natural compounds from Bacopa monnieri. The docking analysis between natural compounds as a ligand and AChE, BuChE as a receptor was completed using MGL tools Autodock 4.2 module. The analysis of the hydrophobic interactions, inhibition constants, and hydrogen bonds may indicates that they play a significant role in finding out the interacting position at the active site. However, after analyzing the binding energy (ΔG), the documented data shows that bacoside X, bacoside A, 3-beta-D-glucosylstigmasterol and daucosterol could be good inhibitors in the inhibition of AChE and BuChE activities. Therefore, our study indicates that the inhibition constants of the aforesaid natural compounds of Bacopa can be utilized for the development of inhibitors.

Synthesis of Silver Nanoparticles using Euphorbia wallichii Extract and Assessment of their Bio-functionalities.

BACKGROUND: Silver nanoparticles synthesized by the bio-green method have been applied to various biomedical applications. These procedures are simple, eco-friendly and serve as an alternative to complex chemical methods for the preparation of nanomaterials. OBJECTIVE: In the present study, phytosynthesis of silver nanoparticles, to examine their antioxidant potential, toxic effects towards bacterial-, fungal-strains, brine shrimp nauplii and cancer cells was focused. METHODS: Methanolic extract of Euphorbia wallichii roots was used for the synthesis of silver nanoparticles. The synthesis was monitored and confirmed by UV-visible spectroscopy, Fourier Transform Infra-Red (FTIR) spectrometric analysis, Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray (EDX) and X-Ray Powder Diffraction (XRD). RESULTS: The synthesized particles were average 63±8 nm in size. Involvement of phenolic (46.7±2.4 µg GAE/mg) and flavonoid (11.7±1.2 µg QE/mg) compounds as capping agents was also measured. Nanoparticles showed antioxidant properties in terms of free radical scavenging potential (59.63±1.0 %), reducing power (44.52±1.34 µg AAE/mg) and total antioxidant capacity (60.48±2.2 µg AAE/mg). The nanoparticles showed potent cytotoxic effects against brine shrimp nauplii (LD50 66.83 µg/ml), proliferation and cell death of HeLa cells as determined by MTT (LD50 0.3923 µg/ml) and TUNEL assays, respectively. Antimicrobial results revealed that silver nanoparticles were found to be more potent against pathogenic fungal (maximum active against A. fumigatus, MIC 15 µg/disc) and bacterial strains (maximum active against S. aureus, MIC 3.33 µg/disc) than the E. wallichii extract alone. CONCLUSION: These results support the advantages of using an eco-friendly and cost-effective method for synthesis of nanoparticles with antioxidant, cytotoxic and antimicrobial potential.

Can Wogonin be Used in Controlling Diabetic Cardiomyopathy?

Diabetes Mellitus (DM) is now a well-known factor which initiates many metabolic derangements in various tissues and organs including liver, muscle, pancreas, adipose tissue, cardiovascular and nervous system. Cardiovascular complications are the most crucial , and their effects are so intensive that their derangement leads to cardiac failure even in the absence of ischemic heart diseases. This entity of cardiac pathology in DM is often regarded as diabetic cardiomyopathy (DCM). Recently, many plant-derived drugs have been tested to control and alleviate DCM. Wogonin is one of the drugs the characteristics of which have been deeply studied. Wogonin is a flavonoid having yellow color pigment in their leaves and is obtained from the roots of plant Scutellaria Baicalensis Georgi. Wogonin has long been used as an active anti-cancer drug in Chinese medicine practice. In recent past wogonin has shown to possess notable anti-inflammatory, and anti-allergic properties. Wogonin has demonstrated to possess anti-oxidant, anti-viral, anti-inflammatory and also anti-thrombotic properties. Wogonin has shown to alleviate apoptosis, and ER stress in the cells and this property can also be used in the treatment of cardiovascular diseases. Notably, wogonin has been documented to have an extensive margin of safety as well as displays little or no organ toxicity following extended intravenous administration. In this review, we discuss recently discovered therapeutic potential of wogonin in the treatment of DCM.

Wogonin Alleviates Hyperglycemia Through Increased Glucose Entry into Cells Via AKT/GLUT4 Pathway.

Insulin resistance and type 2 Diabetes mellitus resulting in chronic hyperglycemia is a major health problem in the modern world. Many drugs have been tested to control hyperglycemia which is believed to be the main factor behind many of the diabetes-related late-term complications. Wogonin is a famous herbal medicine which has been shown to be effective in controlling diabetes and its complications. In our previous work, we showed that wogonin is beneficial in many ways in controlling diabetic cardiomyopathy. In this review, we mainly explained wogonin anti-hyperglycemic property through AKT/GLUT4 pathway. Here we briefly discussed that wogonin increases Glut4 trafficking to plasma membrane which allows increased entry of glucose and thus alleviates hyperglycemia. Conclusion: Wogonin can be used as an anti-diabetic and anti-hyperglycemic drug and works via AKT/GLUT4 pathway.

Isolation and Characterization of Nuciferoic Acid, a Novel Keto Fatty Acid with Hyaluronidase Inhibitory Activity from Cocos nucifera Linn. Endocarp.

BACKGROUND: Inflammation and oxidative stress are very closely related to pathophysiological processes and linked to multiple chronic diseases. Traditionally, the coconut fruits were used in Guatemala for treatment of dermatitis and inflammation. Isolation of the anti-inflammatory agent from the hard shell of the coconut fruit was targeted in the current study. METHODS: Fractionation of ethanolic extract of the coconut hard shell was done by using column chromatography, solvent treatments and TLC that led to the isolation of a molecule. RESULTS AND DISCUSSION: Spectral characterization of the molecule by LC-MS/MS QTOF, FTIR, 1HNMR, 13C-NMR, HMQC and HMBC indicated that it is a novel keto fatty acid, which is named as nuciferoic acid. Hyaluronidase inhibitory potential of the nuciferoic acid was found to be moderate. It was further docked in all the ten cavities of hyaluronidase and was compared with the substrate hyaluronic acid. Cavity 1 and cavity 4 could be the probable sites of action on hyaluronidase for nuciferoic acid. ADME and toxicological characterization suggested that the key sites of metabolism on nuciferoic acid are C1, C2, C14 and C17. Toxicity prediction against 55 toxicological endpoints revealed that nuciferoic acid does not have any indication of existing toxicological features. CONCLUSION: A novel keto fatty acid, nuciferoic acid, from C. nucifera hard shell has been isolated and characterized. It was found to inhibit hyaluronidase activity, which indicated its potential application as an anti-inflammatory drug or as an adjuvant.

Essential Oils: Extraction Techniques, Pharmaceutical And Therapeutic Potential - A Review.

BACKGROUND: Essential oils are liquid extracts from aromatic plants, which have numerous applications in multiple industries. There are a variety of methods used for the extraction of essential oils, with each method exhibiting certain advantages and determining the biological and physicochemical properties of the extracted oils. Essential oils from different plant species contain more than 200 constituents which are comprised of volatile and non-volatile components. The application of essential oils as antimicrobial, anticancer, anti-inflammatory and anti-viral agents is due to their effective and efficient properties, inter alia. METHOD: Several advanced (supercritical fluid extraction, subcritical extraction liquid, solvent-free microwave extraction) and conventional (hydrodistillation, steam distillation, hydrodiffusion, solvent extraction) methods have been discussed for the extraction of essential oils. Advanced methods are considered as the most promising extraction techniques due to less extraction time, low energy consumption, low solvent used and less carbon dioxide emission. CONCLUSION: This manuscript reviewed the major research studies in the field and discussed several research findings on the chemical composition of essential oils, methods of oil extraction, and application of these oils in pharmaceutical and therapeutic fields. These essential oils can be used as anticancer, antimicrobial, antiviral, and as skin permeation enhancer agents.

Relationship between CNS and Immunology: Correlation with Psychology.

BACKGROUND: Higher animals, especially the human beings have the privilege of employing advanced central nervous system (CNS) as well as the evolved immune system to ward off various onslaughts throughout their life. Alterations in inflammatory and neural regulatory pathways lead to several disorders that are now becoming the cause of concern across the world. Deregulation in bidirectional network, particularly in aging population, leads to several neurodegenerative diseases such as dementia as a one of the major characteristics. OBJECTIVE: Interestingly, research updates have signified the role of abrupt immune regulation in several brain diseases, establishing a link between altered immune system and CNS related diseases. In the later period of life, the altered immune response in the pathogenesis of major psychiatric disorders, has become more visible. In the present manuscript, we present a synopsis on the linkage of CNS and immune system with respect to psychology, with the aim to further understand the biological machinery of psychoneuroimmunological disorders. The immune system of human being plays an important role in keeping pathogen onslaughts on bay. CONCLUSION: Our manuscript concludes a close relationship between emotion and psychology to diseases and immunology, proclaiming the need of providing enhanced attention on mechanistic aspect of psychoneuroimmunological disorders.

Plant-derived mPGES-1 inhibitors or suppressors: A new emerging trend in the search for small molecules to combat inflammation.

Inflammation comprises the reaction of the body to injury, in which a series of changes of the terminal vascular bed, blood, and connective tissue tends to eliminate the injurious agent and to repair the damaged tissue. It is a complex process, which involves the release of diverse regulatory mediators. The current anti-inflammatory agents are challenged by multiple side effects and thus, new effective therapies are highly needed. The aim of this review is to summarize the described microsomal prostaglandin E synthase-1 (mPGES-1) inhibitors or transcriptional suppressors from medicinal plants, which could be an ideal approach in the management of inflammatory disorders, but need further clinical trials in order to be ultimately validated.

Preventive and Therapeutic Potentials of Anthocyanins in Diabetes and Associated Complications.

Diet is an essential factor affecting the development of and risk for diabetes mellitus. In search of preventative and therapeutic strategies, the potential role of certain foods and their bioactive compounds to prevent the pathogenesis associated with metabolic diseases is to be considered. Human consumption of anthocyanins is among the highest of all flavonoids. Epidemiological studies have suggested that the consumption of anthocyanins lowers the risk of diabetes and diabetic complications. Anthocyanins are important natural bioactive pigments responsible for red to blue colour of fruits, leaves, seeds, stems and flowers, which are present in a variety of plant species particularly in berries and cherries. A large number of bioactive anthocyanins, such as cyanidin, malvidin, delphinidin, pelargonidin, peonidin, petunidin and their metabolites have shown multiple biological activities with apparent effects on glucose absorption, glucose uptake, insulin secretion and sensitivity, on the enzymes involved in glucose metabolism, gene expressions, inflammatory mediators, glucose transporters in progression of diabetes and associated complications, such as diabetic retinopathy, nephropathy, neuropathy and diabetic vascular diseases. The versatility of the anthocyanins provides a promising approach for diabetes management than synthetic drugs. Here we summarize the effect of several anthocyanins on many in vitro, in vivo and clinical studies and also reveal the mechanisms which could prevent or reverse the underlying mechanisms of diabetic pathologies including promotion of antioxidant, antihyperlipidemic, anti-inflammatory and anti-apoptotic activities.

Antiplatelet Potential of Plant-Derived Glycosides as Possible Lead Compounds.

BACKGROUND: Blood platelets are crucial for maintaining hemostasis and several events in the woundhealing. However, platelet up-regulation leads to the development and the complications of several cardiovascular diseases. For the effective management of these complications, several synthetic drugs are in clinical practice such as aspirin, warfarin and other drugs. since a long time. But some adverse reactions like aspirin resistance and bleed disorders cause patient incompliance and reduce their therapeutic potential. Thus, the search for potent and safer antiplatelet agents is of great interest. METHODS: Various search engines such as Google, GoogleScholar, PubMed and ScienceDirect were used for the search of antiplatelet glycosides. All peered review journals were considered in the review. RESULTS: Glycoside is a class of naturally-occurring organic compounds that are frequently found in the plant kingdom. Similarly, platelet aggregation beyond the purpose of hemostasis is the underlying cause of blood clottingrelated diseases. The results showed strong potential of plant derived glycosides in various preclinical studies. CONCLUSIONS: This review presents a thorough understanding of plant-derived glycosides as antiplatelet agents with a possible mechanism of action based on the existing literature. In addition, this review discusses the possibility of formulating antiplatelet medications from plant glycosides with strong safety profile. On the basis of strong finding, clinical studies are recommended to ascertain their therapeutic utility.

Evaluation of Anti-Inflammatory Properties of Isoorientin Isolated from Tubers of Pueraria tuberosa.

Inflammation is the major causative factor of different diseases such as cardiovascular disease, diabetes, obesity, osteoporosis, rheumatoid arthritis, inflammatory bowel disease, and cancer. Anti-inflammatory drugs are often the first step of treatment in many of these diseases. The present study is aimed at evaluating the anti-inflammatory properties of isoorientin, a selective cyclooxygenase-2 (COX-2) inhibitor isolated from the tubers of Pueraria tuberosa, in vitro on mouse macrophage cell line (RAW 264.7) and in vivo on mouse paw edema and air pouch models of inflammation. Isoorientin reduced inflammation in RAW 264.7 cell line in vitro and carrageenan induced inflammatory animal model systems in vivo. Cellular infiltration into pouch tissue was reduced in isoorientin treated mice compared to carrageenan treated mice. Isoorientin treated RAW 264.7 cells and animals showed reduced expression of inflammatory proteins like COX-2, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), 5-lipoxygenase (5-LOX), and interleukin 1-ß (IL-1-ß) both in vitro and in vivo. The antioxidant enzyme levels of catalase and GST were markedly increased in isoorientin treated mice compared to carrageenan treated mice. These results suggest that isoorientin, a selective inhibitor of COX-2, not only exerts anti-inflammatory effects in LPS induced RAW cells and carrageenan induced inflammatory model systems but also exhibits potent antioxidant properties.

A Current Perspective on the Inhibition of Cholinesterase by Natural and Synthetic Inhibitors.

Majority of the observed cognitive and behavioral changes in Alzheimer's disease are postulated to be due to the deficiencies in cholinergic pathways of the brain. Enhancement of cholinergic transmission may thus stimulate the cholinergic receptors or prolong the availability of acetylcholine in synaptic cleft and hence improve the Alzheimer's disease associated symptoms. Of these two, the inhibition of cholinesterases (Acetylcholinesterase and Butyrylcholinesterase) by cholinesterase inhibitors is suggested to be a promising strategy. In this regard, various agents both natural and non-natural have been evaluated for the inhibition of cholinesterases. Phytochemical studies of some of the medicinal plants have shown the presence of many valuable compounds that show a wide range of pharmacological activity against cholinesterase enzymes. Interestingly, a good number of potent synthetic inhibitors of cholinesterase enzymes reported so far are natural-product based. This article aims to provide a comprehensive overview of both natural and synthetic cholinesterase inhibitors reported so far. Presenting a comparative overview of synthetic and natural cholinesterase inhibitors may provide some leads for the synthesis of new cholinesterase inhibitors from medicinal plants. Structural activity relationship of the active cholinesterase inhibitors is also discussed with some insights from simulation studies. Insights for possible future research have also been highlighted.