Disaccharide Trehalose in Experimental Therapies for Neurodegenerative Disorders: Molecular Targets and Translational Potential

Small heat shock protein B8: from cell functions to its involvement in diseases and potential therapeutic applications

Heat shock protein family B (small) member 8 (HSPB8) is a 22 kDa ubiquitously expressed protein belonging to the family of small heat shock proteins. HSPB8 is involved in various cellular mechanisms mainly related to proteotoxic stress response and in other processes such as inflammation, cell division, and migration. HSPB8 binds misfolded clients to prevent their aggregation by assisting protein refolding or degradation through chaperone-assisted selective autophagy. In line with this function, the pro-degradative activity of HSPB8 has been found protective in several neurodegenerative and neuromuscular diseases characterized by protein misfolding and aggregation. In cancer, HSPB8 has a dual role being capable of exerting either a pro- or an anti-tumoral activity depending on the pathways and factors expressed by the model of cancer under investigation. Moreover, HSPB8 exerts a protective function in different diseases by modulating the inflammatory response, which characterizes not only neurodegenerative diseases, but also other chronic or acute conditions affecting the nervous system, such as multiple sclerosis and intracerebellar hemorrhage. Of note, HSPB8 modulation may represent a therapeutic approach in other neurological conditions that develop as a secondary consequence of other diseases. This is the case of cognitive impairment related to diabetes mellitus, in which HSPB8 exerts a protective activity by assuring mitochondrial homeostasis. This review aims to summarize the diverse and multiple functions of HSPB8 in different pathological conditions, focusing on the beneficial effects of its modulation. Drug-based and alternative therapeutic approaches targeting HSPB8 and its regulated pathways will be discussed, emphasizing how new strategies for cell and tissue-specific delivery represent an avenue to advance in disease treatments.

Decoding stress granules dynamics: Implications for neurodegenerative disease

Stress granules (SGs) are membrane-less cytoplasmic structures formed by cells in response to external stress, primarily composed of mRNA and proteins. The dynamic properties of their assembly, maintenance, and disassembly play crucial roles in cellular homeostasis. Recent studies have increasingly revealed that aberrations in SGs dynamics are closely related to the pathogenesis of various neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. This review summarizes the latest research progress on SGs dynamics in neurodegenerative diseases. It begins with an overview of the basic biological characteristics of SGs and their functions in neurons, followed by an in-depth exploration of the mechanisms and regulatory pathways of SGs dynamics. The review then summarizes potential therapeutic strategies targeting SGs dynamics abnormalities, particularly through small molecule drugs to modulate SGs formation and disassembly, aiming to delay or halt the progression of neurodegenerative diseases. The review also highlights the application prospects of these interventions in treating neurodegenerative diseases. Finally, the review introduces current techniques used to study SGs dynamics, discussing their advantages, limitations, and future development possibilities. This review aims to provide researchers with a comprehensive perspective to advance the understanding and clinical application of SGs dynamics in the field of neurodegenerative diseases.

APOE4 impairs macrophage lipophagy and promotes demyelination of spiral ganglion neurons in mouse cochleae

The ApoE-ε4 gene is a well-established genetic risk factor for neurodegenerative diseases, such as Alzheimer's disease and multiple sclerosis, which are characterized by axonal demyelination in the central nervous system. Recent studies have implicated ApoE-ε4 in age-related hearing loss (ARHL), suggesting a potential role of APOE4 isoform in peripheral nervous system degeneration. However, the role of APOE4 in ARHL are still unclear. In this study, we explored the potential role of APOE4 in axonal demyelination of spiral ganglion neurons (SGNs). ApoE-ε4/ε4 (APOE4) and ApoE-ε3/ε3 (APOE3) mice were used to characterize SGNs. The effect of APOE4 on phagocytosis and autophagy as well as intracellular cholesterol level was evaluated in resident cochlear macrophages (RCMs) and mouse bone marrow-derived macrophages (BMDMs). The results showed that significant axonal demyelination was observed in SGNs of 10-month-old APOE4 mice, accompanied by the presence of myelin debris engulfed by RCMs. Meanwhile, inhibited phagocytosis of myelin debris and impaired lipophagy were detected in APOE4 RCMs and APOE4 BMDMs with an aberrant accumulation of lipid droplets (LDs), which could be reversed by trehalose treatment. This study provided a deep insight into the pathogenesis of APOE4-induced axonal demyelination of SGNs associated with the impaired lipophagy in RCMs, which helped to elucidate the underlying mechanism of ApoE-ε4 in ARHL.

Quantitative Analysis of the Influence of Trehalose on Amyloid-β Binding to Membranes by Localized Surface Plasmon Resonance Spectroscopy

The damaging effect of amyloid-β (Aβ) on cellular membranes is an essential factor that contributes to Aβ's neurotoxicity in Alzheimer's disease. In this work, we explore the role of trehalose sugar in protecting model lipid membranes composed of DPPC-POPC-Cholesterol against Aβ toxicity. We used localized surface plasmon resonance (LSPR) spectroscopy and conducted a quantitative analysis to study the influence of trehalose on Aβ-membrane interactions. The LSPR data indicate that trehalose can effectively reduce the level of binding of Aβ to the lipid membrane, indicating its protective role against amyloid toxicity. Additionally, atomic force microscopy (AFM) was used to visualize the lipid membranes supported on the LSPR sensors and to elucidate the effect of trehalose on membrane morphology. The ability of trehalose to alter the physical properties of model membranes is discussed in relation to its protective role against Aβ during dehydration.

Trehalose induces bladder smooth muscle hypercontractility in mice: involvement of oxidative stress and cellular senescence

Autophagy, a conserved catabolic process, is critical for cellular homeostasis and its dysregulation has been implicated in a number of conditions including hypertension, obesity and bladder dysfunctions. The autophagy inducer trehalose has shown promise in treating diseases; however, some studies have reported detrimental effects in vascular tissue under health conditions. In the bladder, the effects of trehalose remain unclear. Therefore, in the present study, male C57BL6/JUnib mice (8 weeks old) were divided into control and trehalose-treated groups (120 mg/mouse/day via gavage) for 4 weeks. After treatment, bladders were harvested for functional, biochemical, and molecular analyses. The trehalose treatment increased the bladder smooth muscle (BSM) contractility to carbachol (CCh), without altering relaxation response to isoproterenol. The CCh-induced BSM hypercontractility was completely abolished by the in vitro incubation of apocynin and diphenyleneiodonium (DPI), implicating NADPH oxidase-derived reactive oxygen species (ROS) on this process. Accordingly, increased levels of superoxide anion (O2-) were found in the urothelial layer, but not in BSM, of trehalose-treated mice. Trehalose also increased senescence-associated β-galactosidase activity in the bladder but failed to upregulate autophagy-related proteins LAMP1 and Beclin-1 in the bladder. Collectively, we show for the first time that trehalose induces BSM hypercontractility in mice, linked to increased levels of O2- and senescent cell, independently of autophagy activation. Therefore, trehalose administration is an effective model for studying BSM hypercontractility in mice, particularly associated with oxidative stress and cellular senescence.

The Spectrum of Small Heat Shock Protein B8 (HSPB8)-Associated Neuromuscular Disorders

The heat shock protein B8 (HSPB8) is one of the small heat shock proteins (sHSP or HSPB) and is a ubiquitous protein in various organisms, including humans. It is highly expressed in skeletal muscle, heart, and neurons. It plays a crucial role in identifying misfolding proteins and participating in chaperone-assisted selective autophagy (CASA) for the removal of misfolded and damaged, potentially cytotoxic proteins. Mutations in HSPB8 can cause distal hereditary motor neuropathy (dHMN), Charcot-Marie-Tooth (CMT) disease type 2L, or myopathy. The disease can manifest from childhood to mid-adulthood. Most missense mutations in the N-terminal and α-crystallin domains of HSPB8 lead to dHMN or CMT2L. Frameshift mutations in the C-terminal domain (CTD), resulting in elongation of the HSPB8 C-terminal, cause myopathy with myofibrillar pathology and rimmed vacuoles. Myopathy and motor neuropathy can coexist. HSPB8 frameshift mutations in the CTD result in HSPB8 mutant aggregation, which weakens the CASA ability to direct misfolded proteins to autophagic degradation. Cellular and animal models indicate that HSPB8 mutations drive pathogenesis through a toxic gain-of-function mechanism. Currently, no cure is available for HSPB8-associated neuromuscular disorders, but numerous therapeutic strategies are under investigation spanning from small molecules to RNA interference to exogenous HSPB8 delivery.

Integrating 2D NMR-based metabolomics and in vitro assays to explore the potential viability of cultivated Ophiocordyceps sinensis as an alternative to the wild counterpart

Ophiocordyceps sinensis is widely used to treat various diseases and as a health supplement. The present study comprehensively compared the metabolic differences between wild and cultivated O. sinensis through 2D 1H-13C HSQC-based metabolomics, and assessed their anti-lung cancer activity on A549 cells. To characterize the global metabolic profile, sample preparation was scrutinously optimized, and both polar (1:4 methanol-water) and non-polar (1:4 methanol-chloroform) extracts of O. sinensis were investigated. A total of 47 and 10 metabolites were identified in the polar and non-polar extracts, respectively. Principal Component Analysis (PCA) revealed greater differences between the two types of O. sinensis in the polar extracts than in the non-polar extracts. Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) together with univariate tests captured 23 and 19 differential spectral features (with 22 and 11 of them assigned) between wild and cultivated O. sinensis in the polar and non-polar extracts, respectively. Meanwhile, the anti-lung cancer activities of both polar and non-polar extracts of wild and cultivated O. sinensis were assessed by MTS assay on A549 cells, and the sterols found in non-polar extracts, such as ergosterol, ergosterol peroxide, and 9,11-dehydroergosterol peroxide, and β-sitosterol, are the active ingredients with potential anti-lung cancer properties. In this study, we introduced a comprehensive strategy integrating 2D NMR-based metabolomics with in vitro assays for comparing the chemical composition and assessing the pharmacological activity of wild and cultivated O. sinensis. Our results provided a scientific basis for the potential viability of cultivated O. sinensis as an alternative to the wild counterpart.

Trehalose Inhibits ferroptosis Through Activating SIRT3/SOD2 Signaling Axis and Alleviates Brain Injury After Traumatic Brain Injury

Trehalose has neuroprotective effects in neurodegenerative diseases. This study aimed to explore the impact of trehalose on traumatic brain injury (TBI) by investigating its role in neuroprotection. The TBI mice model was established utilizing the cortical impact technique followed by trehalose treatment. Traumatic neuronal injury induced by scratch followed by trehalose treatment was performed to mimic TBI in vitro. Memory function was assessed using the Water maze test. Brain damage was evaluated through various methods including brain water content analysis, Nissl staining, Evans blue exudation, and TUNEL staining. Biochemical and morphological changes related to ferroptosis post-TBI were also examined. The results showed that trehalose was found to enhance spatial memory, reduce brain injury, and inhibit ferroptosis in TBI mice, similar to ferroptosis inhibitors. The influence of trehalose on TBI was reversed by the SIRT3 inhibitor. Trehalose upregulated SIRT3 to increase SOD activity in TBI, which could also be counteracted by the SIRT3 inhibitor. Combining trehalose with a ferroptosis inhibitor had a more significant effect on reducing brain injury and inhibiting ferroptosis. Furthermore, in TBI mice treated with trehalose and SIRT3 inhibitors, the effect of trehalose was reversed by SIRT3 inhibitors, but the addition of ferroptosis inhibitors reversed the effect of SIRT3 inhibitors, as shown by decreased ferroptosis and neuronal apoptosis in damaged brain tissue. In summary, this study provides initial evidence that trehalose plays a crucial role in neuroprotection post-TBI through the SIRT3/SOD2 pathway-mediated ferroptosis.

Novel Role of Pin1-Cis P-Tau-ApoE Axis in the Pathogenesis of Preeclampsia and Its Connection with Dementia

Preeclampsia (preE) is a severe multisystem hypertensive syndrome of pregnancy associated with ischemia/hypoxia, angiogenic imbalance, apolipoprotein E (ApoE)-mediated dyslipidemia, placental insufficiency, and inflammation at the maternal-fetal interface. Our recent data further suggest that preE is associated with impaired autophagy, vascular dysfunction, and proteinopathy/tauopathy disorder, similar to neurodegenerative diseases such as Alzheimer's disease (AD), including the presence of the cis stereo-isoform of phosphorylated tau (cis P-tau), amyloid-β, and transthyretin in the placenta and circulation. This review provides an overview of the factors that may lead to the induction and accumulation of cis P-tau-like proteins by focusing on the inactivation of peptidyl-prolyl cis-trans isomerase (Pin1) that catalyzes the cis to trans isomerization of P-tau. We also highlighted the novel role of the Pin1-cis P-tau-ApoE axis in the development of preE, and propagation of cis P-tau-mediated abnormal protein aggregation (tauopathy) from the placenta to cerebral tissues later in life, leading to neurodegenerative conditions. In the case of preE, proteinopathy/tauopathy may interrupt trophoblast differentiation and induce cell death, similar to the events occurring in neurons. These events may eventually damage the endothelium and cause systemic features of disorders such as preE. Despite impressive research and therapeutic advances in both fields of preE and neurodegenerative diseases, further investigation of Pin1-cis P-tau and ApoE-related mechanistic underpinnings may unravel novel therapeutic options, and new transcriptional and proteomic markers. This review will also cover genetic polymorphisms in the ApoE alleles leading to dyslipidemia induction that may regulate the pathways causing preE or dementia-like features in the reproductive age or later in life, respectively.

Effects of trehalose on bone healing, physical function, and pain in patients with pertrochanteric fractures: a randomized controlled trial protocol

BACKGROUND

Appropriate management of fractures is crucial for restoring natural bone function and preventing long-term complications. Previous research on animal models indicates that trehalose can improve bone fracture healing by inhibiting the inflammatory cascade. We hope that trehalose can accelerate bone fracture healing in humans, alleviate pain, and ultimately enhance the individual's quality of life.

METHODS

This randomized, double-blind clinical trial will be conducted at Taleghani Hospital in Tehran, Iran. Sixty-four patients admitted to the orthopedic ward will be enrolled based on eligibility criteria. The participants will be randomly allocated based on the permuted block randomization into two groups: those receiving trehalose (32 patients) or placebo (32 patients). The patients in the trehalose and placebo groups will receive 3.3 g of trehalose or placebo for 12 weeks, respectively. A consent form, general questionnaire, as well as the Visual Analog Scale (VAS), Harris Hip Score (HHS), and radiological analyses will be used to assess fracture healing quality. The intention-to-treat principle will form the basis of the statistical analysis.

DISCUSSION

The trial results may provide a convenient and safe adjuvant treatment option for the Pertrochanteric Fractures population.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials. IRCT20240605062013N1. URL of the trial registry record: https://irct.behdasht.gov.ir/trial/77212 . Registration date: 16 June 2024.

Programmed cell death: molecular mechanisms, biological functions, diseases, and therapeutic targets

Programmed cell death represents a precisely regulated and active cellular demise, governed by a complex network of specific genes and proteins. The identification of multiple forms of programmed cell death has significantly advanced the understanding of its intricate mechanisms, as demonstrated in recent studies. A thorough grasp of these processes is essential across various biological disciplines and in the study of diseases. Nonetheless, despite notable progress, the exploration of the relationship between programmed cell death and disease, as well as its clinical application, are still in a nascent stage. Therefore, further exploration of programmed cell death and the development of corresponding therapeutic methods and strategies holds substantial potential. Our review provides a detailed examination of the primary mechanisms behind apoptosis, autophagy, necroptosis, pyroptosis, and ferroptosis. Following this, the discussion delves into biological functions and diseases associated dysregulated programmed cell death. Finally, we highlight existing and potential therapeutic targets and strategies focused on cancers and neurodegenerative diseases. This review aims to summarize the latest insights on programmed cell death from mechanisms to diseases and provides a more reliable approach for clinical transformation.

Natural products that alleviate depression: The putative role of autophagy

Major depressive disorder (MDD) is a common mental disorder that severely disrupts psychosocial function and decreases the quality of life. Although the pathophysiological mechanism underlying MDD is complex and remains unclear, emerging evidence suggests that autophagy dysfunction plays a role in MDD occurrence and progression. Natural products serve as a major source of drug discovery and exert tremendous potential in developing antidepressants. Recently published reports are paying more attention on the autophagy regulatory effect of antidepressant natural products. In this review, we comprehensively discuss the abnormal changes occurred in multiple autophagy stages in MDD patients, and animal and cell models of depression. Importantly, we emphasize the regulatory mechanism of antidepressant natural products on disturbed autophagy, including monomeric compounds, bioactive components, crude extracts, and traditional Chinese medicine formulae. Our comprehensive review suggests that enhancing autophagy might be a novel approach for MDD treatment, and natural products restore autophagy homeostasis to facilitate the renovation of mitochondria, impede neuroinflammation, and enhance neuroplasticity, thereby alleviating depression.

Targeting selective autophagy in CNS disorders by small-molecule compounds

Autophagy functions as the primary cellular mechanism for clearing unwanted intracellular contents. Emerging evidence suggests that the selective elimination of intracellular organelles through autophagy, compared to the increased bulk autophagic flux, is crucial for the pathological progression of central nervous system (CNS) disorders. Notably, autophagic removal of mitochondria, known as mitophagy, is well-understood in an unhealthy brain. Accumulated data indicate that selective autophagy of other substrates, including protein aggregates, liposomes, and endoplasmic reticulum, plays distinctive roles in various pathological stages. Despite variations in substrates, the molecular mechanisms governing selective autophagy can be broadly categorized into two types: ubiquitin-dependent and -independent pathways, both of which can be subjected to regulation by small-molecule compounds. Notably, natural products provide the remarkable possibility for future structural optimization to regulate the highly selective autophagic clearance of diverse substrates. In this context, we emphasize the selectivity of autophagy in regulating CNS disorders and provide an overview of chemical compounds capable of modulating selective autophagy in these disorders, along with the underlying mechanisms. Further exploration of the functions of these compounds will in turn advance our understanding of autophagic contributions to brain disorders and illuminate precise therapeutic strategies for these diseases.

Trehalose Attenuates In Vitro Neurotoxicity of 6-Hydroxydopamine by Reducing Oxidative Stress and Activation of MAPK/AMPK Signaling Pathways

The effects of trehalose, an autophagy-inducing disaccharide with neuroprotective properties, on the neurotoxicity of parkinsonian mimetics 6-hydroxydopamine (6-OHDA) and 1-methyl-4-phenylpiridinium (MPP+) are poorly understood. In our study, trehalose suppressed 6-OHDA-induced caspase-3/PARP1 cleavage (detected by immunoblotting), apoptotic DNA fragmentation/phosphatidylserine externalization, oxidative stress, mitochondrial depolarization (flow cytometry), and mitochondrial damage (electron microscopy) in SH-SY5Y neuroblastoma cells. The protection was not mediated by autophagy, autophagic receptor p62, or antioxidant enzymes superoxide dismutase and catalase. Trehalose suppressed 6-OHDA-induced activation of c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), and AMP-activated protein kinase (AMPK), as revealed by immunoblotting. Pharmacological/genetic inhibition of JNK, p38 MAPK, or AMPK mimicked the trehalose-mediated cytoprotection. Trehalose did not affect the extracellular signal-regulated kinase (ERK) and mechanistic target of rapamycin complex 1 (mTORC1)/4EBP1 pathways, while it reduced the prosurvival mTORC2/AKT signaling. Finally, trehalose enhanced oxidative stress, mitochondrial damage, and apoptosis without decreasing JNK, p38 MAPK, AMPK, or AKT activation in SH-SY5Y cells exposed to MPP+. In conclusion, trehalose protects SH-SY5Y cells from 6-OHDA-induced oxidative stress, mitochondrial damage, and apoptosis through autophagy/p62-independent inhibition of JNK, p38 MAPK, and AMPK. The opposite effects of trehalose on the neurotoxicity of 6-OHDA and MPP+ suggest caution in its potential development as a neuroprotective agent.

Unlocking Trehalose's versatility: A comprehensive Journey from biosynthesis to therapeutic applications

For over forty years, a sugar of rare configuration known as trehalose (two molecules of glucose linked at their 1-carbons), has been recognised for more than just its roles as a storage compound. The ability of trehalose to protect an extensive range of biological materials, for instance cell lines, tissues, proteins and DNA, has sparked considerable interest in the biotechnology and pharmaceutical industries. Currently, trehalose is now being investigated as a promising therapeutic candidate for human use, as it has shown potential to reduce disease severity in various experimental models. Despite its diverse biological effects, the precise mechanism underlying this observation remain unclear. Therefore, this review delves into the significance of trehalose biosynthesis pathway in the development of novel drug, investigates the inhibitors of trehalose synthesis and evaluates the binding efficiency of T6P with TPS1. Additionally, it also emphasizes the knowledge about the protective effect of trehalose on modulation of autophagy, combating viral infections, addressing the conditions like cancer and neurodegenerative diseases based on the recent advancement. Furthermore, review also highlight the trehalose's emerging role as a surfactant in delivering monoclonal antibodies that will further broadening its potential application in biomedicines.

The autophagy paradox: A new hypothesis in neurodegenerative disorders

A recent study showed that while autophagy is usually tied to protein and organelle turnover, it can also play dual roles in neurodegenerative diseases. Traditionally, autophagy was seen as protective since it removes damaged proteins and organelles. but new data suggests autophagy can sometimes promote neuron death. and This review tackles autophagy's seemingly contradictory effects in neurodegeneration, or the "autophagy paradox. " It offers a framework for understanding autophagy in neurodegenerative research and the cellular processes involved. In short, our data uncovers a harmful autophagy role in certain situations, conflicting the view that it's always beneficial. We describe the distinct, disease-specific autophagy pathways functioning in various neurodegenerative diseases. Part two concerns potential therapeutic implications of manipulating autophagy and current strategies targeting the autophagic system, suggesting interesting areas for future research into tailored modulators. This could eventually enable activating or controlling specific autophagy pathways and aid in developing more effective treatments. Researchers believe more molecular-level research is needed so patient-tailored autophagy-modulating therapeutics can be developed given this dilemma. Moreover, research must translate faster into effective neurodegenerative disease treatment options. This article aims to provide a wholly new perspective on autophagy's classically described role in these severe diseases, challenging current dogma and opening new therapeutic avenue options.

Trehalose prevents the formation of aggregates of mutant ataxin-3 and reduces soluble ataxin-3 protein levels in an SCA3 cell model

Spinocerebellar ataxia type 3 (SCA3) is a neurodegenerative disorder caused by mutant ataxin-3 with an abnormally expanded polyQ tract and is the most common dominantly inherited ataxia worldwide. There are no suitable therapeutic options for this disease. Autophagy, a defense mechanism against the toxic effects of aggregation-prone misfolded proteins, has been shown to have beneficial effects on neurodegenerative diseases. Thus, trehalose, which is an autophagy inducer, may have beneficial effects on SCA3. In the present study, we examined the effects of trehalose on an SCA3 cell model. After trehalose treatment, aggregate formation, soluble ataxin-3 protein levels and cell viability were evaluated in HEK293T cells overexpressing ataxin-3-15Q or ataxin-3-77Q. We also explored the mechanism by which trehalose affects autophagy and stress pathways. A filter trap assay showed that trehalose decreased the number of aggregates formed by mutant ataxin-3 containing an expanded polyQ tract. Western blot and Cell Counting Kit-8 (CCK-8) results demonstrated that trehalose also reduced the ataxin-3 protein levels and was safe for ataxin-3-expressing cells, respectively. Western blot and total antioxidant capacity assays suggested that trehalose had great therapeutic potential for treating SCA3, likely through its antioxidant activity. Our data indicate that trehalose plays a neuroprotective role in SCA3 by inhibiting the aggregation and reducing the protein level of ataxin-3, which is also known to protect against oxidative stress. These findings provide a new insight into the possibility of treating SCA3 with trehalose and highlight the importance of inducing autophagy in SCA3.

Friend or foe: The role of stress granule in neurodegenerative disease

Stress granules (SGs) are dynamic membraneless organelles that form in response to cellular stress. SGs are predominantly composed of RNA and RNA-binding proteins that assemble through liquid-liquid phase separation. Although the formation of SGs is considered a transient and protective response to cellular stress, their dysregulation or persistence may contribute to various neurodegenerative diseases. This review aims to provide a comprehensive overview of SG physiology and pathology. It covers the formation, composition, regulation, and functions of SGs, along with their crosstalk with other membrane-bound and membraneless organelles. Furthermore, this review discusses the dual roles of SGs as both friends and foes in neurodegenerative diseases and explores potential therapeutic approaches targeting SGs. The challenges and future perspectives in this field are also highlighted. A more profound comprehension of the intricate relationship between SGs and neurodegenerative diseases could inspire the development of innovative therapeutic interventions against these devastating diseases.

Effect of trehalose on mortality and disease severity in ICU-admitted patients: Protocol for a triple-blind, randomized, placebo-controlled clinical trial

Background

Improvement in organ failure in intensive care unit (ICU) patients is accompanied by lower mortality rate. A disaccharide, trehalose is a candidate to improve organ failure and survival by autophagy induction and enhancing oxidative stress defense. The aim of this study is to assess the effectiveness of trehalose in improving clinical outcome and reducing mortality in ICU patients.

Methods

a triple-blind, randomized, placebo-controlled, two arm, parallel-group, superiority clinical trial will enroll 200 ICU-admitted patients at Imam Reza hospital, Mashhad, Iran. The patients will be randomly allocated to receive either a 100 ml solution of 15 % trehalose or normal saline intravenously. Primary outcomes include ICU mortality and 60-day mortality, while secondary outcomes focus on blood parameters on day 5 and length of hospital/ICU stay.

Conclusion

Trehalose has demonstrated beneficial effects in diverse patients; however, no study has evaluated its effect in all ICU-admitted patients. Consequently, this study provides an opportunity to investigate whether trehalose's anti-inflammatory effects, mediated by inducing autophagy and enhancing oxidative stress defense, can play a role in reducing mortality and improving clinical outcomes in the critically ill patients. If successful, trehalose could offer a potential therapeutic approach in the ICU setting.

The AKT2/SIRT5/TFEB pathway as a potential therapeutic target in non-neovascular AMD

Non-neovascular or dry age-related macular degeneration (AMD) is a multi-factorial disease with degeneration of the aging retinal-pigmented epithelium (RPE). Lysosomes play a crucial role in RPE health via phagocytosis and autophagy, which are regulated by transcription factor EB/E3 (TFEB/E3). Here, we find that increased AKT2 inhibits PGC-1α to downregulate SIRT5, which we identify as an AKT2 binding partner. Crosstalk between SIRT5 and AKT2 facilitates TFEB-dependent lysosomal function in the RPE. AKT2/SIRT5/TFEB pathway inhibition in the RPE induced lysosome/autophagy signaling abnormalities, disrupted mitochondrial function and induced release of debris contributing to drusen. Accordingly, AKT2 overexpression in the RPE caused a dry AMD-like phenotype in aging Akt2 KI mice, as evident from decline in retinal function. Importantly, we show that induced pluripotent stem cell-derived RPE encoding the major risk variant associated with AMD (complement factor H; CFH Y402H) express increased AKT2, impairing TFEB/TFE3-dependent lysosomal function. Collectively, these findings suggest that targeting the AKT2/SIRT5/TFEB pathway may be an effective therapy to delay the progression of dry AMD.

Trehalose Protects against Superoxide Dismutase 1 Proteinopathy in an Amyotrophic Lateral Sclerosis Model

This work aimed to study the effect of trehalose in protecting cells against Sod1 proteinopathy associated with amyotrophic lateral sclerosis (ALS). Humanized yeast cells in which native Sod1 was replaced by wild-type human Sod1 or an ALS mutant (WT-A4V Sod1 heterodimer) were used as the experimental model. Cells were treated with 10% trehalose (p/v) before or after the appearance of hSod1 proteinopathy induced by oxidative stress. In both conditions, trehalose reduced the number of cells with Sod1 inclusions, increased Sod1 activity, and decreased the levels of intracellular oxidation, demonstrating that trehalose avoids Sod1 misfolding and loss of function in response to oxidative stress. The survival rates of ALS Sod1 cells stressed in the presence of trehalose were 60% higher than in their absence. Treatment with trehalose after the appearance of Sod1 inclusions in cells expressing WT Sod1 doubled longevity; after 5 days, non-treated cells did not survive, but 15% of cells treated with sugar were still alive. Altogether, our results emphasize the potential of trehalose as a novel therapy, which might be applied preventively in ALS patients with a family history of the disease or after diagnosis in ALS patients who discover the disease following the first symptoms.

Targeting autophagy impairment improves the phenotype of a novel CLN8 zebrafish model

CLN8 is an endoplasmic reticulum cargo receptor and a regulator of lysosome biogenesis whose loss of function leads to neuronal ceroid lipofuscinosis. CLN8 has been linked to autophagy and lipid metabolism, but much remains to be learned, and there are no therapies acting on the molecular signatures in this disorder. The present study aims to characterize the molecular pathways involved in CLN8 disease and, by pinpointing altered ones, to identify potential therapies. To bridge the gap between cell and mammalian models, we generated a new zebrafish model of CLN8 deficiency, which recapitulates the pathological features of the disease. We observed, for the first time, that CLN8 dysfunction impairs autophagy. Using autophagy modulators, we showed that trehalose and SG2 are able to attenuate the pathological phenotype in mutant larvae, confirming autophagy impairment as a secondary event in disease progression. Overall, our successful modeling of CLN8 defects in zebrafish highlights this novel in vivo model's strong potential as an instrument for exploring the role of CLN8 dysfunction in cellular pathways, with a view to identifying small molecules to treat this rare disease.

Protective effect of trehalose sugar on amyloid-membrane interactions using BLM electrophysiology

Alzheimer's disease (AD) is a neurodegenerative disease characterized by dementia and memory loss in the elderly population. The amyloid-β peptide (Aβ) is one of the main pathogenic factors in AD and is known to cause damage to neuronal cellular membranes. There is no cure currently available for AD, and new approaches, including preventive strategies, are highly desirable. In this work, we explore the possibility of protecting neuronal membranes from amyloid-induced damage with naturally existing sugar trehalose. Trehalose has been shown to protect plant cellular membranes in extreme conditions and modify Aβ misfolding. We hypothesize that trehalose can protect the neuronal membrane from amyloid toxicity. In this work, we studied the protective effect of trehalose against Aβ1-42-induced damage in model lipid membranes (DPPC/POPC/cholesterol) using atomic force microscopy and black lipid membrane electrophysiology. Our results demonstrate that Aβ1-42 damaged membranes and led to ionic current leakage across these membranes due to the formation of various defects and pores. The presence of trehalose reduced the ion current across membranes caused by Aβ1-42 peptide damage, thus efficiently protecting the membranes. These findings suggest that the trehalose sugar can potentially be useful in protecting neuronal membranes against amyloid toxicity in AD.

Effect of Trehalose Disaccharide on Activation of Microglia and Indices of Systemic Inflammation in an Experimental Model of Alzheimer's Disease

In an experimental model of Alzheimer's disease in mice, oral administration of trehalose disaccharide reduces neuroinflammation assessed by the expression level of microglia activation marker Iba1 and affects the neutrophil degranulation activity. A potential anti-inflammatory effect of 4% trehalose solution associated with a decrease in the activity of leukocyte elastase in plasma was revealed.

Exploiting sweet relief for preeclampsia by targeting autophagy-lysosomal machinery and proteinopathy

The etiology of preeclampsia (PE), a severe complication of pregnancy with several clinical manifestations and a high incidence of maternal and fetal morbidity and mortality, remains unclear. This issue is a major hurdle for effective treatment strategies. We recently demonstrated that PE exhibits an Alzheimer-like etiology of impaired autophagy and proteinopathy in the placenta. Targeting of these pathological pathways may be a novel therapeutic strategy for PE. Stimulation of autophagy with the natural disaccharide trehalose and its lacto analog lactotrehalose in hypoxia-exposed primary human trophoblasts restored autophagy, inhibited the accumulation of toxic protein aggregates, and restored the ultrastructural features of autophagosomes and autolysosomes. Importantly, trehalose and lactotrehalose inhibited the onset of PE-like features in a humanized mouse model by normalizing autophagy and inhibiting protein aggregation in the placenta. These disaccharides restored the autophagy-lysosomal biogenesis machinery by increasing nuclear translocation of the master transcriptional regulator TFEB. RNA-seq analysis of the placentas of mice with PE indicated the normalization of the PE-associated transcriptome profile in response to trehalose and lactotrehalose. In summary, our results provide a novel molecular rationale for impaired autophagy and proteinopathy in patients with PE and identify treatment with trehalose and its lacto analog as promising therapeutic options for this severe pregnancy complication.

Autophagic-lysosomal damage induced by swainsonine is protected by trehalose through activation of TFEB-regulated pathway in renal tubular epithelial cells

Swainsonine (SW) is the main toxic component of locoweed. Previous studies have shown that kidney damage is an early pathologic change in locoweed poisoning in animals. Trehalose induces autophagy and alleviates lysosomal damage, while its protective effect and mechanism against the toxic injury induced by SW is not clear. Based on the published literature, we hypothesize that transcription factor EB(TFEB) -regulated is targeted by SW and activating TFEB by trehalose would reverse the toxic effects. In this study, we investigate the mechanism of protective effects of trehalose using renal tubular epithelial cells. The results showed that SW induced an increase in the expression level of microtubule-associated protein light chain 3-II and p62 proteins and a decrease in the expression level of ATPase H+ transporting V1 Subunit A, Cathepsin B, Cathepsin D, lysosome-associated membrane protein 2 and TFEB proteins in renal tubular epithelial cells in a time and dose-dependent manner suggesting TFEB-regulated lysosomal pathway is adversely affected by SW. Conversely, treatment with trehalose, a known activator of TFEB promote TFEB nuclear translocation suggesting that TFEB plays an important role in protection against SW toxicity. We demonstrated in lysosome staining that SW reduced the number of lysosomes and increased the luminal pH, while trehalose could counteract these SW-induced effects. In summary, our results demonstrated for the first time that trehalose could alleviate the autophagy degradation disorder and lysosomal damage induced by SW. Our results provide an interesting method for reversion of SW-induced toxicity in farm animals and furthermore, activation of TFEB by trehalose suggesting novel mechanism of treating lysosomal storage diseases.

Allulose mitigates chronic enteritis by reducing mitochondria dysfunction via regulating cathepsin B production

Metabolic changes have been linked to the development of inflammatory bowel disease (IBD), which includes colitis. Allulose, an endogenous bioactive monosaccharide, is vital to the synthesis of numerous compounds and metabolic processes within living organisms. Nevertheless, the precise biochemical mechanism by which allulose inhibits colitis remains unknown. Allulose is an essential and intrinsic protector of the intestinal mucosal barrier, as it maintains the integrity of tight junctions in the intestines, according to the current research. It is also important to know that there is a link between the severity of inflammatory bowel disease (IBD) and colorectal cancer (CRC), chemically-induced colitis in rodents, and lower levels of allulose in the blood. Mice with colitis, either caused by dextran sodium sulphate (DSS) or naturally occurring colitis in IL-10-/- mice, had less damage to their intestinal mucosa after being given allulose. Giving allulose to a colitis model starts a chain of reactions because it stops cathepsin B from ejecting and helps lysosomes stick together. This system effectively stops the activity of myosin light chain kinase (MLCK) when intestinal epithelial damage happens. This stops the breakdown of tight junction integrity and the start of mitochondrial dysfunction. To summarise, the study's findings have presented data that supports the advantageous impact of allulose in reducing the advancement of colitis. Its ability to stop the disruption of the intestinal barrier enables this. Therefore, allulose has potential as a medicinal supplement for treating colitis.

The Potentiality of Natural Products and Herbal Medicine as Novel Medications for Parkinson's Disease: A Promising Therapeutic Approach

As the global population ages, the prevalence of Parkinson's disease (PD) is steadily on the rise. PD demonstrates chronic and progressive characteristics, and many cases can transition into dementia. This increases societal and economic burdens, emphasizing the need to find effective treatments. Among the widely recognized causes of PD is the abnormal accumulation of proteins, and autophagy dysfunction accelerates this accumulation. The resultant Lewy bodies are also commonly found in Alzheimer's disease patients, suggesting an increased potential for the onset of dementia. Additionally, the production of free radicals due to mitochondrial dysfunction contributes to neuronal damage and degeneration. The activation of astrocytes and the M1 phenotype of microglia promote damage to dopamine neurons. The drugs currently used for PD only delay the clinical progression and exacerbation of the disease without targeting its root cause, and come with various side effects. Thus, there is a demand for treatments with fewer side effects, with much potential offered by natural products. In this study, we reviewed a total of 14 articles related to herbal medicines and natural products and investigated their relevance to possible PD treatment. The results showed that the reviewed herbal medicines and natural products are effective against lysosomal disorder, mitochondrial dysfunction, and inflammation, key mechanisms underlying PD. Therefore, natural products and herbal medicines can reduce neurotoxicity and might improve both motor and non-motor symptoms associated with PD. Furthermore, these products, with their multi-target effects, enhance bioavailability, inhibit antibiotic resistance, and might additionally eliminate side effects, making them good alternative therapies for PD treatment.

Comparison of various exercise interventions on cognitive function in Alzheimer's patients: A network meta-analysis

OBJECTIVE

Exercise helps enhance cognitive function in Alzheimer's patients, although the most effective forms of exercise remain unknown.

METHODS

This network meta-analysis was registered in INPLASY (INPLASY202330066). According to predetermined criteria, this investigation comprised randomized controlled studies involving exercise therapies in people with Alzheimer's disease. The exercise intervention was ranked using surface under the cumulative ranking curve (SUCRA) and mean ranking, with the critical goal outcomes being overall cognition, executive function, and memory function.

RESULTS

Resistance exercise is the most likely strategy to be beneficial for slowing down overall cognitive function loss in Alzheimer's patients (72.4%). Additionally, multi-component exercise was the most effective way to improve executive function (30.4%). The only type of exercise that significantly affects memory function is resistance exercise. Memory is the cognitive function that is least responsive to exercise.

CONCLUSION

Resistance exercise may be an efficient intervention for overall cognitive function decline in patients with Alzheimer's and conjointly for their memory function. Multi-component exercise is more effective in improving executive function in patients with Alzheimer's disease.

A neuroprotective dose of trehalose is harmless to metabolic organs: comprehensive histopathological analysis of liver, pancreas, and kidney

BACKGROUND

Trehalose is a non-reducing disaccharide synthesized by lower organisms. It has recently received special attention because of its neuroprotective properties by stimulating autophagy in Parkinson's disease (PD) models. Therefore, evaluating whether trehalose affects metabolic organs is vital to determine its neurotherapeutic safety.

METHODS

We validated the trehalose neuroprotective dosage in a PD model induced with intraperitoneal paraquat administration twice weekly for 7 weeks. One week before paraquat administration, mice were treated with trehalose in the drinking water and continued along with paraquat treatment. Histological and morphometrical analyses were conducted on the organs involved in trehalose metabolism, including the liver, pancreas, and kidney.

RESULTS

Paraquat-induced dopaminergic neuronal loss was significantly decreased by trehalose. After trehalose treatment, the liver morphology, the mononucleated/binucleated hepatocytes percentage, and sinusoidal diameter remained unchanged in each liver lobes. Endocrine and exocrine pancreas's histology was not affected, nor was any fibrotic process observed. The islet of Langerhans's structure was preserved when analyzing the area, the largest and smallest diameter, and circularity. Renal morphology remained undamaged, and no changes were identified within the glomerular basement membrane. The renal corpuscle structure did not suffer alterations in the Bowman's space, area, diameter, circularity, perimeter, and cellularity. Besides, the renal tubular structures's luminal area and internal and external diameter were preserved.

CONCLUSION

Our study demonstrates that systemic trehalose administration preserved the typical histological architecture of the organs involved in its metabolism, supporting its safety as a potential neuroprotective agent.

Cellular Stress Impact on Yeast Activity in Biotechnological Processes-A Short Overview

The importance of Saccharomyces cerevisiae yeast cells is known worldwide, as they are the most used microorganisms in biotechnology for bioethanol and biofuel production. Also, they are analyzed and studied for their similar internal biochemical processes to human cells, for a better understanding of cell aging and response to cell stressors. The special ability of S. cerevisiae cells to develop in both aerobic and anaerobic conditions makes this microorganism a viable model to study the transformations and the way in which cellular metabolism is directed to face the stress conditions due to environmental changes. Thus, this review will emphasize the effects of oxidative, ethanol, and osmotic stress and also the physiological and genetic response of stress mitigation in yeast cells.

The AKT2/SIRT5/TFEB pathway as a potential therapeutic target in atrophic AMD

Age-related macular degeneration (AMD), the leading cause of geriatric blindness, is a multi-factorial disease with retinal-pigmented epithelial (RPE) cell dysfunction as a central pathogenic driver. With RPE degeneration, lysosomal function is a core process that is disrupted. Transcription factors EB/E3 (TFEB/E3) tightly control lysosomal function; their disruption can cause aging disorders, such as AMD. Here, we show that induced pluripotent stem cells (iPSC)-derived RPE cells with the complement factor H variant [ CFH (Y402H)] have increased AKT2, which impairs TFEB/TFE3 nuclear translocation and lysosomal function. Increased AKT2 can inhibit PGC1α, which downregulates SIRT5, an AKT2 binding partner. SIRT5 and AKT2 co-regulate each other, thereby modulating TFEB-dependent lysosomal function in the RPE. Failure of the AKT2/SIRT5/TFEB pathway in the RPE induced abnormalities in the autophagy-lysosome cellular axis by upregulating secretory autophagy, thereby releasing a plethora of factors that likely contribute to drusen formation, a hallmark of AMD. Finally, overexpressing AKT2 in RPE cells in mice led to an AMD-like phenotype. Thus, targeting the AKT2/SIRT5/TFEB pathway could be a potential therapy for atrophic AMD.

Trehalose Inhibits Inflammatory Responses through Mitochondrial Reprogramming in RAW 264.7 Macrophages

Studies reported the beneficial effects of trehalose on metabolic syndromes, hyperlipidemia, and autophagy, but its action mechanisms are still poorly understood. Even though trehalose is digested by disaccharidase and absorbed in the intestine, intact molecules encounter immune cells which form a solid balance between the allowance of nutritive substances and the removal of harmful pathogens. In this regard, the polarization of intestinal macrophages into an anti-inflammatory phenotype through metabolic regulation is emerging as a therapeutic strategy for the prevention of gastrointestinal inflammation. The current study investigated the effects of trehalose on immunological phenotypes, energy metabolism, and LPS-induced macrophage mitochondrial functioning. Results indicate that trehalose reduces prostaglandin E₂ and nitric oxide, which are inflammatory mediators of LPS-induced macrophages. In addition, trehalose further significantly suppressed inflammatory cytokines and mediators via energy metabolism reprogramming towards M2-like status in LPS-stimulated macrophages.

Norgestrel causes digestive gland injury in the clam Mactra veneriformis: An integrated histological, transcriptomics, and metabolomics study

The potential adverse effects of progestins on aquatic organisms, especially non-target species, are of increasing concern worldwide. However, the effect and mechanism of progestin toxicity on aquatic invertebrates remain largely unexplored. In the present study, clams Mactra veneriformis were exposed to norgestrel (NGT, 0, 10, and 1000 ng/L), the dominant progestin detected in the aquatic environment, for 21 days. NGT accumulation, histology, transcriptome, and metabolome were assessed in the digestive gland. The bioconcentration factor (BCF) was 386 and 268 in the 10 ng/L NGT group and 1000 ng/L NGT group, respectively, indicating efficient accumulation of NGT in the clams. Histological analysis showed that NGT led to the swelling of epithelial cells and blurring of the basement membrane in the digestive gland. Differentially-expressed genes and KEGG pathway enrichment analysis using a transcriptomic approach suggested that NGT primarily disturbed the detoxification system, antioxidant defense, carbohydrate and amino acid metabolism, and steroid hormone metabolism, which was consistent with the metabolites analyzed using a metabolomic approach. Furthermore, we speculated that the oxidative stress caused by NGT resulted in histological damage to the digestive gland. This study showed that NGT caused adverse effects in the clams and sheds light on the mechanisms of progestin interference in aquatic invertebrates.

Strontium ion attenuates osteoarthritis through inhibiting senescence and enhancing autophagy in fibroblast-like synoviocytes

Osteoarthritis (OA) mainly occurs in the elderly population and seriously affects their quality of life (QOL). Strontium (Sr) ions have shown positive effects on bone tissue and are promising for OA treatment. However, the adequate treatment dosage and underlying mechanisms are unclear. This study investigated the effects and underlying mechanisms of different concentrations of Sr ions in a mouse model of OA induced by destabilization of the medial meniscus (DMM) surgery. DMM-induced OA mice received intra-articular injections of different concentrations of Sr ions, and a suitable concentration of Sr ions was found to improve OA. Furthermore, we investigated the mechanism by which Sr ions mediate senescence and autophagy in fibroblast-like synoviocytes (FLSs) in the synovial tissues of DMM-induced OA mice. OA mice treated with 10 µl of 5 mmol/L SrCl₂ showed the greatest improvement in pain-related behavior and cartilage damage. In addition, in vivo and in vitro experiments revealed that Sr ions inhibit senescence and improve the autophagic function of FLSs. We also found that enhancement of the autophagic function of FLSs could effectively slow down senescence. Therefore, we show that Sr ions through the AMPK/mTOR/LC3B-II signal axis improve FLSs autophagy function and delay FLSs senescence, and furthermore, improve OA. These results suggest that senescence and autophagy function of FLSs may serve as promising targets for OA treatment, and that Sr ions may inhibit OA progression through these two targets.

Recent Update and Drug Target in Molecular and Pharmacological Insights into Autophagy Modulation in Cancer Treatment and Future Progress

Recent evidence suggests that autophagy is a governed catabolic framework enabling the recycling of nutrients from injured organelles and other cellular constituents via a lysosomal breakdown. This mechanism has been associated with the development of various pathologic conditions, including cancer and neurological disorders; however, recently updated studies have indicated that autophagy plays a dual role in cancer, acting as a cytoprotective or cytotoxic mechanism. Numerous preclinical and clinical investigations have shown that inhibiting autophagy enhances an anticancer medicine's effectiveness in various malignancies. Autophagy antagonists, including chloroquine and hydroxychloroquine, have previously been authorized in clinical trials, encouraging the development of medication-combination therapies targeting the autophagic processes for cancer. In this review, we provide an update on the recent research examining the anticancer efficacy of combining drugs that activate cytoprotective autophagy with autophagy inhibitors. Additionally, we highlight the difficulties and progress toward using cytoprotective autophagy targeting as a cancer treatment strategy. Importantly, we must enable the use of suitable autophagy inhibitors and coadministration delivery systems in conjunction with anticancer agents. Therefore, this review briefly summarizes the general molecular process behind autophagy and its bifunctional role that is important in cancer suppression and in encouraging tumor growth and resistance to chemotherapy and metastasis regulation. We then emphasize how autophagy and cancer cells interacting with one another is a promising therapeutic target in cancer treatment.

New developments and opportunities in drugs being trialed for amyotrophic lateral sclerosis from 2020 to 2022

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that primarily affects motor neurons in the brain and spinal cord. In the recent past, there have been just two drugs approved for treatment, riluzole and edaravone, which only prolong survival by a few months. However, there are many novel experimental drugs in development. In this review, we summarize 53 new drugs that have been evaluated in clinical trials from 2020 to 2022, which we have classified into eight mechanistic groups (anti-apoptotic, anti-inflammatory, anti-excitotoxicity, regulated integrated stress response, neurotrophic factors and neuroprotection, anti-aggregation, gene therapy and other). Six were tested in phase 1 studies, 31 were in phase 2 studies, three failed in phase 3 studies and stopped further development, and the remaining 13 drugs were being tested in phase 3 studies, including methylcobalamin, masitinib, MN-166, verdiperstat, memantine, AMX0035, trazodone, CNM-Au8, pridopidine, SLS-005, IONN363, tofersen, and reldesemtiv. Among them, five drugs, including methylcobalamin, masitinib, AMX0035, CNM-Au8, and tofersen, have shown potent therapeutic effects in clinical trials. Recently, AMX0035 has been the third medicine approved by the FDA for the treatment of ALS after riluzole and edaravone.