Phellinus linteus mushroom protects against tacrine-induced mitochondrial impairment and oxidative stress in HepG2 cells

L-Theanine Prolongs the Lifespan by Activating Multiple Molecular Pathways in Ultraviolet C-Exposed Caenorhabditis elegans

L-theanine, a unique non-protein amino acid, is an important bioactive component of green tea. Previous studies have shown that L-theanine has many potent health benefits, such as anti-anxiety effects, regulation of the immune response, relaxing neural tension, and reducing oxidative damage. However, little is known concerning whether L-theanine can improve the clearance of mitochondrial DNA (mtDNA) damage in organisms. Here, we reported that L-theanine treatment increased ATP production and improved mitochondrial morphology to extend the lifespan of UVC-exposed nematodes. Mechanistic investigations showed that L-theanine treatment enhanced the removal of mtDNA damage and extended lifespan by activating autophagy, mitophagy, mitochondrial dynamics, and mitochondrial unfolded protein response (UPRmt) in UVC-exposed nematodes. In addition, L-theanine treatment also upregulated the expression of genes related to mitochondrial energy metabolism in UVC-exposed nematodes. Our study provides a theoretical basis for the possibility that tea drinking may prevent mitochondrial-related diseases.

Phellinus linteus polysaccharides: A review on their preparation, structure-activity relationships, and drug delivery systems

Phellinus linteus polysaccharides exhibit antitumor, immunomodulatory, anti-inflammatory, and antioxidant properties, mitigate insulin resistance, and enhance the diversity and abundance of gut microbiota. However, the bioactivities of P. linteus polysaccharides vary owing to the complex structure, thereby, limiting their application. Various processing strategies have been employed to modify them for improving the functional properties and yield. Herein, we compare the primary modes of extraction and purification employed to improve the yield and purity, review the structure-activity relationships, and discuss the application of P. linteus polysaccharides using nano-carriers for the encapsulation and delivery of various drugs to improve bioactivity. The limitations and future perspectives are also discussed. Exploring the bioactivity, structure-activity relationship, processing methods, and delivery routes of P. linteus polysaccharides will facilitate the development of functional foods and dietary supplements rich in P. linteus polysaccharides.

Tacrine Derivatives in Neurological Disorders: Focus on Molecular Mechanisms and Neurotherapeutic Potential

Tacrine is a drug used in the treatment of Alzheimer's disease as a cognitive enhancer and inhibitor of the enzyme acetylcholinesterase (AChE). However, its clinical application has been restricted due to its poor therapeutic efficacy and high prevalence of detrimental effects. An attempt was made to understand the molecular mechanisms that underlie tacrine and its analogues influence over neurotherapeutic activity by focusing on modulation of neurogenesis, neuroinflammation, endoplasmic reticulum stress, apoptosis, and regulatory role in gene and protein expression, energy metabolism, Ca2+ homeostasis modulation, and osmotic regulation. Regardless of this, analogues of tacrine are considered as a model inhibitor of cholinesterase in the therapy of Alzheimer's disease. The variety both in structural make-up and biological functions of these substances is the main appeal for researchers' interest in them. A new paradigm for treating neurological diseases is presented in this review, which includes treatment strategies for Alzheimer's disease, as well as other neurological disorders like Parkinson's disease and the synthesis and biological properties of newly identified versatile tacrine analogues and hybrids. We have also shown that these analogues may have therapeutic promise in the treatment of neurological diseases in a variety of experimental systems.

Structural diversity and bioactivity of polysaccharides from medicinal mushroom Phellinus spp.: A review

Phellinus spp., an important medicinal fungus mushroom extensively cultivated and consumed in East Asia for over 2000 years, is traditionally considered a precious food supplement and medicinal ingredient. Published studies showed that the polysaccharides are major bioactive macromolecules from Phellinus spp. (PPs) with multiple health-promoting effects, including immunomodulatory, anti-cancer, anti-inflammatory, hepatoprotective, hypoglycemic, hypolipidemic, antioxidant, and other bioactivities. Although the polysaccharides extracted from the fruiting body, mycelium, and fermentation broth of Phellinus spp. have been extensively studied for the extraction and purification methods, structural characteristics, and pharmacological activities, the knowledge for their structures and bioactivity relationship, toxicologic effects, and pharmacokinetic profile is limited. This review systematically summarizes the recent progress in the isolation and purification, chemical structures, bioactivities, and the underlying mechanisms of PPs. Information from this review provides insights into the further development of polysaccharides from PPs as therapeutic agents and functional foods.

Biocapture-Directed Chemical Labeling for Discerning Stressed States of Organelles

Lysosomal rupture engaged in diverse diseases remains poorly discerned from lysosomal membrane permeabilization (LMP). We herein reported biocapture-directed chemical labeling (BCCL) for the discern of lysosomal rupture by tracking the release of optically labeled cathepsins from damaged lysosomes into the cytosol. BCCL entails covalent anchoring of an azide-tagged suicide substrate (Epo-LeuTyr^Az) to the enzyme active site and bioorthogonal ligation of the introduced azide with ^DBCORC, a ratiometric sensor featuring an acidity-reporting red emissive X-rhodamine-lactam (ROX), blue emissive coumarin (CM) inert to pH, and DBCO reactive to azide. Aided with fluorescein isocyanate-labeled sialic acid (FITC-Sia), a probe remained in pH-elevated lysosomes but dissipated from LMP⁺ lysosomes, BCCL enables optical discern of four states of lysosomes: ruptured lysosomes (blue in cytosol), LMP⁺ lysosomes (blue in lysosomes), pH-elevated lysosomes (blue and green in lysosomes), and physiological lysosomes (blue, green and red in lysosomes). This approach could find applicability to study lysosome rupture over LMP in diseases and to evaluate lysosome rupture-inducing drugs.

Hemicellulosic Polysaccharides From Bamboo Leaves Promoted by Phosphotungstic Acids and Its Attenuation of Oxidative Stress in HepG2 Cells

In this work, we exploited an efficient method to release hemicellulosic polysaccharides (BLHP) from bamboo (Phyllostachys pubescens Mazel) leaves assisted by a small amount of phosphotungstic acid. Structural unit analysis proved that BLHP-A1 and BLHP-B1 samples possessed abundant low-branch chains in →4)-β-_D-Xylp-(1→ skeleton mainly consisting of Xylp, Manp, Glcp, Galp, and Araf residues. According to the results of the antioxidant activity assays in vitro, both of the two fractions demonstrated the activity for scavenging DPPH⋅ and ABTS⁺ radicals and exhibited relatively a high reducing ability compared to the recently reported polysaccharides. Moreover, the antioxidant activities of purified polysaccharides were evaluated against H₂O₂-induced oxidative stress damage in HepG2 cells. BLHP-B1 showed more activity for preventing damages from H₂O₂ in HepG2 cells by improving the enzyme activities of SOD, CAT, and GSH-Px and decreasing the production of MDA as well as suppressing reactive oxygen species (ROS) formation. This study implied that BLHP could demonstrate its attenuation ability for oxidative stress in HepG2 cells.

Lysosomal quality control of cell fate: a novel therapeutic target for human diseases

In eukaryotic cells, lysosomes are digestive centers where biological macromolecules are degraded by phagocytosis and autophagy, thereby maintaining cellular self-renewal capacity and energy supply. Lysosomes also serve as signaling hubs to monitor the intracellular levels of nutrients and energy by acting as platforms for the assembly of multiple signaling pathways, such as mammalian target of rapamycin complex 1 (mTORC1) and adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK). The structural integrity and functional balance of lysosomes are essential for cell function and viability. In fact, lysosomal damage not only disrupts intracellular clearance but also results in the leakage of multiple contents, which pose great threats to the cell by triggering cell death pathways, including apoptosis, necroptosis, pyroptosis, and ferroptosis. The collapse of lysosomal homeostasis is reportedly critical for the pathogenesis and development of various diseases, such as tumors, neurodegenerative diseases, cardiovascular diseases, and inflammatory diseases. Lysosomal quality control (LQC), comprising lysosomal repair, lysophagy, and lysosomal regeneration, is rapidly initiated in response to lysosomal damage to maintain lysosomal structural integrity and functional homeostasis. LQC may be a novel but pivotal target for disease treatment because of its indispensable role in maintaining intracellular homeostasis and cell fate.

Therapeutic Effects of Natural Drugs on Alzheimer's Disease

Alzheimer disease (AD) is characterized as a chronic neurodegenerative disease associated with aging. The clinical manifestations of AD include latent episodes of memory and cognitive impairment, psychiatric symptoms and behavioral disorders, as well as limited activities in daily life. In developed countries, AD is now acknowledged as the third leading cause of death, following cardiovascular disease and cancer. The pathogenesis and mechanism of AD remain unclear, although some theories have been proposed to explain AD, such as the theory of β-amyloid, the theory of the abnormal metabolism of tau protein, the theory of free radical damage, the theory of the inflammatory response, the theory of cholinergic damage, etc. Effective methods to predict, prevent or reverse AD are unavailable, and thus the development of new, efficient therapeutic drugs has become a current research hot spot worldwide. The isolation and extraction of active components from natural drugs have great potential in treating AD. These drugs possess the advantages of multiple targets in multiple pathways, fewer side effects and a long duration of curative effects. This article summaries the latest research progress regarding the mechanisms of natural drugs in the treatment of AD, providing a review of the literature and a theoretical basis for improving the clinical treatment of AD.

A Review: The Bioactivities and Pharmacological Applications of Phellinus linteus

Phellinus linteus is a popular medicinal mushroom that is widely used in China, Korea, Japan, and other Asian countries. P. linteus comprises various bioactive components, such as polysaccharides, triterpenoids, phenylpropanoids, and furans, and has proven to be an effective therapeutic agent in traditional Chinese medicine for the treatment and the prevention of various diseases. A number of studies have reported that P. linteus possesses many biological activities useful for pharmacological applications, including anticancer, anti-inflammatory, immunomodulatory, antioxidative, and antifungal activities, as well as antidiabetic, hepatoprotective, and neuroprotective effects. This review article briefly presents the recent progress made in understanding the bioactive components, biological activities, pharmacological applications, safety, and prospects of P. linteus, and provides helpful references and promising directions for further studies of P. linteus.

Hypoglycemic and Hypolipidemic Effects of Phellinus Linteus Mycelial Extract from Solid-State Culture in A Rat Model of Type 2 Diabetes

Hypoglycemic and hypolipidemic effects of P. linteus have been observed in numerous studies, but the underlying molecular mechanisms are unclear. In this study, we prepared P. linteus extract (PLE) from mycelia of solid-state culture, and evaluated its hypoglycemic and hypolipidemic effects in rat models of high-fat diet (HFD)-induced and low-dose streptozotocin (STZ)-induced type 2 diabetes. PLE treatment effectively reduced blood glucose levels, and improved insulin resistance and lipid and lipoprotein profiles. The hypoglycemic effect of PLE was based on inhibition of key hepatic gluconeogenesis enzymes (FBPase, G6Pase) expression and hepatic glycogen degradation, and consequent reduction of hepatic glucose production. PLE also: (i) enhanced expression of CPT1A and ACOX1 (key proteins involved in fatty acid β-oxidation) and low-density lipoprotein receptor (LDLR) in liver, thus promoting clearance of triglycerides and LDL-C; (ii) inhibited expression of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) in liver, thus reducing cholesterol production; (iii) displayed strong hepatoprotective and renal protective effects. Our findings indicate that PLE has strong potential functional food application in adjuvant treatment of type 2 diabetes with dyslipidemia.

Multifunctional properties of novel tacrine congeners: cholinesterase inhibition and cytotoxic activity

This review describes the synthesis of a wide range of novel tetrahydroacridine derivatives (tiocyanates, selenocyanates, ureas, selenoureas, thioureas, isothioureas, disulfides, diselenides and several tacrine homo- and hetro-hybrids). These tacrine congeners exhibit significant anticholinesterase and cytotoxic properties and may therefore be of considerable potential for the development of new drugs for the treatment of Alzheimer's disease.

Antitumor and immunomodulating activities of six Phellinus igniarius polysaccharides of different origins

The aim of the current study was to compare the antitumor efficiency of Phellinus igniarius polysaccharides (PIP) from six different origins and preliminarily investigate its potential mechanisms. PIP was extracted using the microwave extraction method. The corresponding in vivo antitumor efficacy was assessed in Kunming mice bearing H22 tumors and Gansu PIP (GPIP) was identified to have a significantly higher antitumor efficacy compared with the control group (P<0.05), while no significant difference was observed following treatment with PIP from different origins (P>0.05). The spleen index of the GPIP group significantly increased compared with the saline and CTX groups (P<0.01). The in vitro MTT assay of GPIP on HepG2 cells indicated that GPIP had no direct cytotoxicity. The serum immune cytokines of interleukin-2, interleukin-12 and interferon-γ were assessed using the ELISA method. The concentration of all three serum cytokines significantly increased compared with saline and CTX groups (P<0.01) indicating that activating the immune system may be a potential antitumor mechanism. These results demonstrated that GPIP has great potential as a natural antitumor agent with immunomodulatory activity.

Traditional uses, fermentation, phytochemistry and pharmacology of Phellinus linteus: A review

Medicinal mushroom Phellinus linteus ("Sanghuang" in Chinese, ) is a famous fungus which is widely used in China, Korea, and other Asian countries. As a traditional Chinese medicine with a 2000-year long history, medicinal applications of Phellinus linteus mainly include treating hemorrhage, hemostasis and diseases related to female menstruation according to Chinese clinical empirical practice. A number of studies reported Phellinus linteus possessed good therapeutic effects on various ailments including tumor, diabetes, inflammation, obesity, etc. The present paper comprehensively reviewed the traditional uses, fermentation, constituent and pharmacology of Phellinus linteus based on scientific literature as well as critical analysis of the research. This review aimed to provide latest information and new foundations and directions for further investigations on Phellinus linteus. All available information about Phellinus linteus was supplied by library database and electronic search (CNKI, Google Scholar, ScienceDirect, Web of Science, PubMed, etc.). Some local and ancient books as well as brilliant scholars were also important information resources. Improvement of fermentation techniques promoted the production of Phellinus linteus. Studies of constituents showed the main chemical composition of Phellinus linteus included polysaccharides, flavones, triterpenes, aromatic acids, amino acids, etc. and polysaccharides were found to account for the largest proportion. Pharmacological researches revealed Phellinus linteus possessed a variety of biological activities including anti-cancer, immuno-regulation, anti-diabetes, anti-oxidation and anti-inflammation. Based on these summarized information, this review was presented to provide helpful references and beneficial directions for future studies of Phellinus linteus.

Bioactivities and Health Benefits of Mushrooms Mainly from China

Many mushrooms have been used as foods and medicines for a long time. Mushrooms contain polyphenols, polysaccharides, vitamins and minerals. Studies show that mushrooms possess various bioactivities, such as antioxidant, anti-inflammatory, anticancer, immunomodulatory, antimicrobial, hepatoprotective, and antidiabetic properties, therefore, mushrooms have attracted increasing attention in recent years, and could be developed into functional food or medicines for prevention and treatment of several chronic diseases, such as cancer, cardiovascular diseases, diabetes mellitus and neurodegenerative diseases. The present review summarizes the bioactivities and health benefits of mushrooms, and could be useful for full utilization of mushrooms.

Tacrine induces apoptosis through lysosome- and mitochondria-dependent pathway in HepG2 cells

Tacrine (THA) is a competitive inhibitor of cholinesterase. Administration of THA for the treatment of Alzheimer's disease results in a reversible hepatotoxicity in 30-50% of patients, as indicated by elevated alanine aminotransferase levels. However, the intracellular mechanisms have not yet been elucidated. In our previous study, we found that THA induced cytotoxicity and mitochondria dysfunction by ROS generation and 8-OHdG formation in mitochondrial DNA in HepG2 cells. In this study, the mechanism underlying was further investigated. Our results demonstrated that THA induced dose-dependent apoptosis with cytochrome c release and activation of caspase-3. THA-induced apoptosis was inhibited by treating cells with a ROS inhibitor, YCG063. In addition, we observed that THA led to an early lysosomal membrane permeabilization and release of cathepsin B. Pretreatment with CA-074Me, a specific cathepsin B inhibitor resulted in a significant but not complete decrease in tacrine-induced apoptosis. These data suggest that tacrine-induced cell apoptosis involves both mitochondrial damage and lysosomal membrane destabilization, and ROS is the critical factor that integrates tacrine-induced mitochondrial and lysosomal death pathways.

Pharmacogenomics of Alzheimer's disease: novel therapeutic strategies for drug development

Alzheimer's disease (AD) is a major problem of health and disability, with a relevant economic impact on our society. Despite important advances in pathogenesis, diagnosis, and treatment, its primary causes still remain elusive, accurate biomarkers are not well characterized, and the available pharmacological treatments are not cost-effective. As a complex disorder, AD is a polygenic and multifactorial clinical entity in which hundreds of defective genes distributed across the human genome may contribute to its pathogenesis. Diverse environmental factors, cerebrovascular dysfunction, and epigenetic phenomena, together with structural and functional genomic dysfunctions, lead to amyloid deposition, neurofibrillary tangle formation, and premature neuronal death, the major neuropathological hallmarks of AD. Future perspectives for the global management of AD predict that genomics and proteomics may help in the search for reliable biomarkers. In practical terms, the therapeutic response to conventional drugs (cholinesterase inhibitors, multifactorial strategies) is genotype-specific. Genomic factors potentially involved in AD pharmacogenomics include at least five categories of gene clusters: (1) genes associated with disease pathogenesis; (2) genes associated with the mechanism of action of drugs; (3) genes associated with drug metabolism (phase I and II reactions); (4) genes associated with drug transporters; and (5) pleiotropic genes involved in multifaceted cascades and metabolic reactions. The implementation of pharmacogenomic strategies will contribute to optimize drug development and therapeutics in AD and related disorders.