Multifaceted Role of Matrix Metalloproteinases in Neurodegenerative Diseases: Pathophysiological and Therapeutic Perspectives

Current therapy in amyotrophic lateral sclerosis (ALS): A review on past and future therapeutic strategies

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects the first and second motoneurons (MNs), associated with muscle weakness, paralysis and finally death. The exact etiology of the disease still remains unclear. Currently, efforts to develop novel ALS treatments which target specific pathomechanisms are being studied. The mechanisms of ALS pathogenesis involve multiple factors, such as protein aggregation, glutamate excitotoxicity, oxidative stress, mitochondrial dysfunction, apoptosis, inflammation etc. Unfortunately, to date, there are only two FDA-approved drugs for ALS, riluzole and edavarone, without curative treatment for ALS. Herein, we give an overview of the many pathways and review the recent discovery and preclinical characterization of neuroprotective compounds. Meanwhile, drug combination and other therapeutic approaches are also reviewed. In the last part, we analyze the reasons of clinical failure and propose perspective on the treatment of ALS in the future.

Unlocking new avenues for neuropsychiatric disease therapy: the emerging potential of Peroxisome proliferator-activated receptors as promising therapeutic targets

RATIONALE

Peroxisome proliferator-activated receptors (PPARs) are transcription factors that regulate various physiological processes such as inflammation, lipid metabolism, and glucose homeostasis. Recent studies suggest that targeting PPARs could be beneficial in treating neuropsychiatric disorders by modulating neuronal function and signaling pathways in the brain. PPAR-α, PPAR-δ, and PPAR-γ have been found to play important roles in cognitive function, neuroinflammation, and neuroprotection. Dysregulation of PPARs has been associated with neuropsychiatric disorders like bipolar disorder, schizophrenia, major depression disorder, and autism spectrum disorder. The limitations and side effects of current treatments have prompted research to target PPARs as a promising novel therapeutic strategy. Preclinical and clinical studies have shown the potential of PPAR agonists and antagonists to improve symptoms associated with these disorders.

OBJECTIVE

This review aims to provide an overview of the current understanding of PPARs in neuropsychiatric disorders, their potential as therapeutic targets, and the challenges and future directions for developing PPAR-based therapies.

METHODS

An extensive literature review of various search engines like PubMed, Medline, Bentham, Scopus, and EMBASE (Elsevier) databases was carried out with the keywords "PPAR, Neuropsychiatric disorders, Oxidative stress, Inflammation, Bipolar Disorder, Schizophrenia, Major depression disorder, Autism spectrum disorder, molecular pathway".

RESULT & CONCLUSION

Although PPARs present a hopeful direction for innovative therapeutic approaches in neuropsychiatric conditions, additional research is required to address obstacles and convert this potential into clinically viable and individualized treatments.

Exploring the properties and potential of the neural extracellular matrix for next-generation regenerative therapies

The extracellular matrix (ECM) is a dynamic and complex network of proteins and molecules that surrounds cells and tissues in the nervous system and orchestrates a myriad of biological functions. This review carefully examines the diverse interactions between cells and the ECM, as well as the transformative chemical and physical changes that the ECM undergoes during neural development, aging, and disease. These transformations play a pivotal role in shaping tissue morphogenesis and neural activity, thereby influencing the functionality of the central nervous system (CNS). In our comprehensive review, we describe the diverse behaviors of the CNS ECM in different physiological and pathological scenarios and explore the unique properties that make ECM-based strategies attractive for CNS repair and regeneration. Addressing the challenges of scalability, variability, and integration with host tissues, we review how advanced natural, synthetic, and combinatorial matrix approaches enhance biocompatibility, mechanical properties, and functional recovery. Overall, this review highlights the potential of decellularized ECM as a powerful tool for CNS modeling and regenerative purposes and sets the stage for future research in this exciting field. This article is categorized under: Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease Implantable Materials and Surgical Technologies > Nanomaterials and Implants.

Effects of microbiome-based interventions on neurodegenerative diseases: a systematic review and meta-analysis

Neurodegenerative diseases (NDDs) are characterized by neuronal damage and progressive loss of neuron function. Microbiome-based interventions, such as dietary interventions, biotics, and fecal microbiome transplant, have been proposed as a novel approach to managing symptoms and modulating disease progression. Emerging clinical trials have investigated the efficacy of interventions modulating the GM in alleviating or reversing disease progression, yet no comprehensive synthesis have been done. A systematic review of the literature was therefore conducted to investigate the efficacy of microbiome-modulating methods. The search yielded 4051 articles, with 15 clinical trials included. The overall risk of bias was moderate in most studies. Most microbiome-modulating interventions changed the GM composition. Despite inconsistent changes in GM composition, the meta-analysis showed that microbiome-modulating interventions improved disease burden (SMD, - 0.57; 95% CI - 0.93 to - 0.21; I2 = 42%; P = 0.002) with a qualitative trend of improvement in constipation. However, current studies have high methodological heterogeneity and small sample sizes, requiring more well-designed and controlled studies to elucidate the complex linkage between microbiome, microbiome-modulating interventions, and NDDs.

Unique transcriptional signatures correlate with behavioral and psychological symptom domains in Alzheimer's disease

Despite the significant burden, cost, and worse prognosis of Alzheimer's disease (AD) with behavioral and psychological symptoms of dementia (BPSD), little is known about the molecular causes of these symptoms. Using antemortem assessments of BPSD in AD, we demonstrate that individual BPSD can be grouped into 4 domain factors in our cohort: affective, apathy, agitation, and psychosis. Then, we performed a transcriptome-wide analysis for each domain utilizing bulk RNA-seq of post-mortem anterior cingulate cortex (ACC) tissues. Though all 4 domains are associated with a predominantly downregulated pattern of hundreds of differentially expressed genes (DEGs), most DEGs are unique to each domain, with only 22 DEGs being common to all BPSD domains, including TIMP1. Weighted gene co-expression network analysis (WGCNA) yielded multiple transcriptional modules that were shared between BPSD domains or unique to each domain, and NetDecoder was used to analyze context-dependent information flow through the biological network. For the agitation domain, we found that all DEGs and a highly associated transcriptional module were functionally enriched for ECM-related genes including TIMP1, TAGLN, and FLNA. Another unique transcriptional module also associated with the agitation domain was enriched with genes involved in post-synaptic signaling, including DRD1, PDE1B, CAMK4, and GABRA4. By comparing context-dependent changes in DEGs between cases and control networks, ESR1 and PARK2 were implicated as two high-impact genes associated with agitation that mediated significant information flow through the biological network. Overall, our work establishes unique targets for future study of the biological mechanisms of BPSD and resultant drug development.

Synergizing drug repurposing and target identification for neurodegenerative diseases

Despite dedicated research efforts, the absence of disease-curing remedies for neurodegenerative diseases (NDDs) continues to jeopardize human society and stands as a challenge. Drug repurposing is an attempt to find new functionality of existing drugs and take it as an opportunity to discourse the clinically unmet need to treat neurodegeneration. However, despite applying this approach to rediscover a drug, it can also be used to identify the target on which a drug could work. The primary objective of target identification is to unravel all the possibilities of detecting a new drug or repurposing an existing drug. Lately, scientists and researchers have been focusing on specific genes, a particular site in DNA, a protein, or a molecule that might be involved in the pathogenesis of the disease. However, the new era discusses directing the signaling mechanism involved in the disease progression, where receptors, ion channels, enzymes, and other carrier molecules play a huge role. This review aims to highlight how target identification can expedite the whole process of drug repurposing. Here, we first spot various target-identification methods and drug-repositioning studies, including drug-target and structure-based identification studies. Moreover, we emphasize various drug repurposing approaches in NDDs, namely, experimental-based, mechanism-based, and in silico approaches. Later, we draw attention to validation techniques and stress on drugs that are currently undergoing clinical trials in NDDs. Lastly, we underscore the future perspective of synergizing drug repurposing and target identification in NDDs and present an unresolved question to address the issue.

Sirtuin dysregulation in Parkinson's disease: Implications of acetylation and deacetylation processes

Parkinson's disease (PD) is a progressive neurodegenerative condition that primarily affects motor function and is caused by a gradual decline of dopaminergic neurons in the brain's substantia pars compacta (Snpc) region. Multiple molecular pathways are involved in the pathogenesis, which results in impaired cellular functions and neuronal degeneration. However, the role of sirtuins, a type of NAD+-dependent deacetylase, in the pathogenesis of Parkinson's disease has recently been investigated. Sirtuins are essential for preserving cellular homeostasis because they control a number of biological processes, such as metabolism, apoptosis, and DNA repair. This review shed lights on the dysregulation of sirtuin activity in PD, highlighting the role that acetylation and deacetylation processes play in the development of the disease. Key regulators of protein acetylation, sirtuins have been found to be involved in the aberrant acetylation of vital substrates linked to PD pathology when their balance is out of balance. The hallmark characteristics of PD such as neuroinflammation, oxidative stress, and mitochondrial dysfunction have all been linked to the dysregulation of sirtuin expression and activity. Furthermore, we have also explored how the modulators of sirtuins can be a promising therapeutic intervention in the treatment of PD.

Matrix Metalloproteinase-9 Testing of Golden Rice Cookies With Piper Crocatum Active Extract for Preventing Foot Ulcers in Patients With Diabetes: Protocol for a Randomized Controlled Trial

BACKGROUND

Diabetic foot ulcers (DFUs) present a formidable challenge to both patients and health care systems. DFUs significantly reduce the quality of life for patients, prolong hospital stays, and are the cause of approximately 70,000 lower limb amputations across the globe annually. Prevention of DFUs primarily involves the optimization of blood sugar levels and the effective management of complications, particularly peripheral neuropathy. Golden Rice has been proven to lower blood sugar levels due to its beta-carotene content, and Piper crocatum (P. crocatum) has been found to be effective in reducing the risk factors of DFUs through biomolecular regulation because of its polyphenol content.

OBJECTIVE

The principal objective of this study is to identify the efficacy of P. crocatum-enriched cookies, with Golden Rice as their primary ingredient, in preventing DFUs. The evaluation will center on their impact on the expression of matrix metalloproteinase-9 (MMP-9), a pivotal factor in the development of DFUs.

METHODS

This study is an experimental clinical research that follows the randomized controlled trial method and uses a single-blind design. The participants in the study are outpatients from primary health centers in Makassar, Indonesia, who have been diagnosed with diabetes mellitus. The sample for the study will be randomly selected and subsequently categorized into 2 groups: the intervention group and the control group. The intervention group consumes P. crocatum-enriched Golden Rice cookies, while the control group receives cookies without these additives. The participants from both groups will consume their respective cookies (packaged identically) twice a day for 14 days. The cookies will be prepared according to a modified recipe with an emphasis on low glucose content, resulting in 51 calories per cookie, comprising 1% carbohydrates, 6% fat, 4% cholesterol, and 4% fiber, excluding gluten, sugar, and salt. They will be baked at 158°C for 20 minutes. The process involves the addition of 20% Golden Rice and 10% P. crocatum ethanol extract, both prepared via maceration with 96% ethanol. The dependent variable in this study is the expression of gelatinases matrix metalloproteinase, to be assessed at 2 distinct time points-preintervention (pretest) and postintervention (posttest)-with the evaluation conducted through the western blotting method.

RESULTS

The recruitment and testing phase started in January 2024. The study is scheduled to be completed by the end of March 2024. Data analysis will commence in April 2024, and the publication of the results is anticipated in the same year (2024). The study will report on the changes in primary data, encompassing gelatinases matrix metalloproteinase, as well as secondary data, including the ankle-brachial index, neuropathy score, and random blood glucose level.

CONCLUSIONS

The findings of this trial are expected to significantly impact the selection of strategies by health care practitioners to enhance diabetes self-management, particularly in the domain of therapeutic snacking, for patients diagnosed with diabetes mellitus.

TRIAL REGISTRATION

Thai Clinical Trials Registry TCTR20230502001; https://www.thaiclinicaltrials.org/show/TCTR20230502001.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/49940.

Microglia in brain aging: An overview of recent basic science and clinical research developments

Aging is characterized by progressive degeneration of tissues and organs, and it is positively associated with an increased mortality rate. The brain, as one of the most significantly affected organs, experiences age-related changes, including abnormal neuronal activity, dysfunctional calcium homeostasis, dysregulated mitochondrial function, and increased levels of reactive oxygen species. These changes collectively contribute to cognitive deterioration. Aging is also a key risk factor for neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. For many years, neurodegenerative disease investigations have primarily focused on neurons, with less attention given to microglial cells. However, recently, microglial homeostasis has emerged as an important mediator in neurological disease pathogenesis. Here, we provide an overview of brain aging from the perspective of the microglia. In doing so, we present the current knowledge on the correlation between brain aging and the microglia, summarize recent progress of investigations about the microglia in normal aging, Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, and then discuss the correlation between the senescent microglia and the brain, which will culminate with a presentation of the molecular complexity involved in the microglia in brain aging with suggestions for healthy aging.

Neuroprotective Effect of Resveratrol against Manganese-Induced Oxidative Stress and Matrix Metalloproteinase-9 in an "In Vivo" Model of Neurotoxicity

Chronic exposure to manganese (Mn) leads to its accumulation in the central nervous system (CNS) and neurotoxicity with not well-known mechanisms. We investigated the involvement of matrix metalloproteinase (MMP)-2 and -9 in Mn neurotoxicity in an in vivo model of rats treated through an intraperitoneal injection, for 4 weeks, with 50 mg/kg of MnCl2 in the presence or in the absence of 30 mg/kg of resveratrol (RSV). A loss of weight was observed in Mn-treated rats compared with untreated and RSV-treated rats. A progressive recovery of body weight was detected in rats co-treated with Mn and RSV. The analysis of brain homogenates indicated that RSV counteracted the Mn-induced increase in MMP-9 levels and reactive oxygen species production as well as the Mn-induced decrease in superoxide dismutase activity and glutathione content. In conclusion, Mn exposure, resulting in MMP-9 induction with mechanisms related to oxidative stress, represents a risk factor for the development of CNS diseases.

The Effect of Rubus idaeus Polyphenols Extract in Induced Endometriosis in Rats

Endometriosis is a common gynecological condition with a complex physio-pathological background. This study aimed to assess the role of Rubus idaeus leaf extract (RiDE) as a potential therapeutic agent in reducing the size of the endometriotic lesions and modulate the plasma expression of MMP-2, MMP-9, and TGF-β1. The endometriotic lesions were induced in a rat model by the autologous transplant of endometrium. Thirty-six female rats, Wistar breed, with induced endometriosis, were divided into four groups and underwent treatment for 28 days. The CTRL group received 0.5 mL/day of the vehicle; the DG group received 1 mg/kg b.w./day dienogest; the RiDG group received 0.25 mL/kg b.w./day RiDE and the D+RiDG group received 1 mg/kg b.w./day dienogest and 0.25 mL/kg b.w./day RiDE, respectively. Rats' weight, endometriotic lesion diameter and grade, and plasma levels of MMP-2, MMP-9, and TGF-β1 were assessed before and after treatment. The administration of RiDE in association with dienogest vs. dienogest determined a lower weight gain and a reduction in diameter of the endometriotic lesions. RiDE administration restored MMP2 and MMP9 plasma levels to initial conditions. Rubus idaeus extract may help in reducing dienogest-associated weight gain, lower the size of endometriotic lesions, and have anti-inflammatory effects through MMP2 and MMP9 reduction.

A Brain-Protective Sterol from Soft Coral Inhibits Lipopolysaccharide-Induced Matrix Metalloproteinase-9-Mediated Astrocytic Migration

Matrix metalloproteinases (MMPs), which are proteolytic enzymes, promote blood-brain barrier (BBB) disruption, leading to neuronal damage and neuroinflammation. Among them, MMP-9 upregulation serves as an inflammatory biomarker in the central nervous system (CNS). Currently, the development of marine organism-derived bioactive compounds or metabolites as anti-inflammatory drugs has received considerable attention. The 9,11-secosteroid, 3β,11-dihydroxy-9,11-secogorgost-5-en-9-one (4p3f), is a novel sterol compound extracted from the soft coral Sinularia leptoclado with potential anti-inflammatory activity. However, the effect of and potential for brain protection of 4p3f on brain astrocytes remain unclear. Herein, we used rat brain astrocytes (RBAs) to investigate the effects and signaling mechanisms of 4p3f on lipopolysaccharide (LPS)-induced MMP-9 expression via zymographic, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), Western blot, immunofluorescence staining, promoter-reporter, and cell migration analyses. We first found that 4p3f blocked LPS-induced MMP-9 expression in RBAs. Next, we demonstrated that LPS induced MMP-9 expression via the activation of ERK1/2, p38 MAPK, and JNK1/2, which is linked to the STAT3-mediated NF-κB signaling pathway. Finally, 4p3f effectively inhibited LPS-induced upregulation of MMP-9-triggered RBA cell migration. These data suggest that a novel sterol from soft coral, 4p3f, may have anti-inflammatory and brain-protective effects by attenuating these signaling pathways of MMP-9-mediated events in brain astrocytes. Accordingly, the soft coral-derived sterol 4p3f may emerge as a potential candidate for drug development or as a natural compound with neuroprotective properties.

Mechanistic Implications of GSK and CREB Crosstalk in Ischemia Injury

Ischemia-reperfusion (IR) injury is a damage to an organ when the blood supply is less than the demand required for normal functioning, leading to exacerbation of cellular dysfunction and death. IR injury occurs in different organs like the kidney, liver, heart, brain, etc., and may not only involve the ischemic organ but also cause systemic damage to distant organs. Oxygen-glucose deprivation in cells causes oxidative stress, calcium overloading, inflammation, and apoptosis. CREB is an essential integrator of the body's various physiological systems, and it is widely accepted that dysfunction of CREB signaling is involved in many diseases, including ischemia-reperfusion injury. The activation of CREB can provide life to a cell and increase the cell's survival after ischemia. Hence, GSK/CREB signaling pathway can provide significant protection to cells of different organs after ischemia and emerges as a futuristic strategy for managing ischemia-reperfusion injury. Different signaling pathways such as MAPK/ERK, TLR4/MyD88, RISK, Nrf2, and NF-κB, get altered during IR injury by the modulation of GSK-3 and CREB (cyclic AMP response element (CRE)-binding protein). GSK-3 (protein kinase B) and CREB are the downstream targets for fulfilling the roles of various signaling pathways. Calcium overloading during ischemia increases the expression of calcium-calmodulin-dependent protein kinase (CaMK), which subsequently activates CREB-mediated transcription, thus promoting the survival of cells. Furthermore, this review highlights the crosstalk between GSK-3 and CREB, promoting survival and rendering the cells resistant to subsequent severe ischemia.

Pharmacological modulation of HIF-1 in the treatment of neuropsychiatric disorders

Hypoxia-inducible factor 1 has been identified as an important therapeutic target in psychiatric illnesses. Hypoxia is a condition in which tissues do not receive enough oxygen, resulting in less oxidative energy production. HIF-1, the master regulator of molecular response to hypoxia, is destabilized when oxygen levels fall. HIF-1, when activated, increases the gene transcription factors that promote adaptive response and longevity in hypoxia. HIF-regulated genes encode proteins involved in cell survival, energy metabolism, angiogenesis, erythropoiesis, and vasomotor control. Multiple genetic and environmental variables contribute to the pathophysiology of psychiatric disease. This review focuses on the most recent findings indicating the role of oxygen deprivation in CNS damage, with strong attention on HIF-mediated pathways. Several pieces of evidence suggested that, in the case of hypoxia, induction and maintenance of HIF-1 target genes may help reduce nerve damage. Major new insights into the molecular mechanisms that control HIF's sensitivity to oxygen are used to make drugs that can change the way HIF works as a therapeutic target for some CNS diseases.

Nuclear orphan receptors: A novel therapeutic agent in neuroinflammation

Orphan receptors constitute a historically varied subsection of a superfamily of nuclear receptors. Nuclear receptors regulate gene expression in response to ligand signals and are particularly alluring therapeutic targets for chronic illnesses. Neuroinflammation and neurodegenerative diseases have been linked to these orphan nuclear receptors. Preclinical and clinical evidence suggests that orphan receptors could serve as future targets in neuroinflammation, such as Parkinson's disease (PD), Alzheimer's Disease (AD), Huntington's Disease (HD), Multiple Sclerosis (MS), and Cerebral Ischemia. Given the therapeutic relevance of certain orphan receptors in a variety of disorders, their potential in neuroinflammation remains unproven. There is substantial evidence that ligand-activated transcription factors have great promise for preventing neurodegenerative and neurological disorders, with certain orphan nuclear receptors i.e., PPARγ, NR4As, and orphan GPCRs holding particularly high potential. Based on previous findings, we attempted to determine the contribution of PPAR, NR4As, and orphan GPCRs-regulated neuroinflammation to the pathogenesis of these disorders and their potential to become novel therapeutic targets.

Computational Studies to Understand the Neuroprotective Mechanism of Action Basil Compounds

Neurodegenerative diseases, such as Alzheimer's and Parkinson's, pose a significant global health challenge, emphasizing the need for novel neuroprotective agents. Basil (Ocimum spp.) has been recognized for its therapeutic potential, and numerous studies have reported neuroprotective effects. In this manuscript, we present a computational protocol to extricate the underlying mechanism of action of basil compounds in neuroprotective effects. Molecular docking-based investigation of the chemical interactions between selected bioactive compounds from basil and key neuroprotective targets, including AChE, GSK3β, γ-secretase, and sirtuin2. Our results demonstrate that basil compound myricerone caffeoyl ester possesses a high affinity of -10.01 and -8.85 kcal/mol against GSK3β and γ-secretase, respectively, indicating their potential in modulating various neurobiological processes. Additionally, molecular dynamics simulations were performed to explore the protein-ligand complexes' stability and to analyze the bound basil compounds' dynamic behavior. This comprehensive computational investigation enlightens the putative mechanistic basis for the neuroprotective effects of basil compounds, providing a rationale for their therapeutic use in neurodegenerative disorders after further experimental validation.

Neurobiochemical characteristics of arginine-rich peptides explain their potential therapeutic efficacy in neurodegenerative diseases

Neurodegenerative diseases, including Alzheimer̕ s disease (AD), Parkinson̕ s disease (PD), Huntington̕ s disease (HD), and Amyotrophic Lateral Sclerosis (ALS) require special attention to find new potential treatment methods. This review aims to summarize the current knowledge of the relationship between the biochemical properties of arginine-rich peptides (ARPs) and their neuroprotective effects to deal with the harmful effects of risk factors. It seems that ARPs have portrayed a promising and fantastic landscape for treating neurodegeneration-associated disorders. With multimodal mechanisms of action, ARPs play various unprecedented roles, including as the novel delivery platforms for entering the central nervous system (CNS), the potent antagonists for calcium influx, the invader molecules for targeting mitochondria, and the protein stabilizers. Interestingly, these peptides inhibit the proteolytic enzymes and block protein aggregation to induce pro-survival signaling pathways. ARPs also serve as the scavengers of toxic molecules and the reducers of oxidative stress agents. They also have anti-inflammatory, antimicrobial, and anti-cancer properties. Moreover, by providing an efficient nucleic acid delivery system, ARPs can play an essential role in developing various fields, including gene vaccines, gene therapy, gene editing, and imaging. ARP agents and ARP/cargo therapeutics can be raised as an emergent class of neurotherapeutics for neurodegeneration. Part of the aim of this review is to present recent advances in treating neurodegenerative diseases using ARPs as an emerging and powerful therapeutic tool. The applications and progress of ARPs-based nucleic acid delivery systems have also been discussed to highlight their usefulness as a broad-acting class of drugs.

Therapeutic implications of phosphorylation- and dephosphorylation-dependent factors of cAMP-response element-binding protein (CREB) in neurodegeneration

Neurodegeneration is a condition of the central nervous system (CNS) characterized by loss of neural structures and function. The most common neurodegenerative disorders (NDDs) include Alzheimer's disease (AD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), multiple sclerosis (MS), motor neuron disorders, psychological disorders, dementia with vascular dementia (VaD), Lewy body dementia (DLB), epilepsy, cerebral ischemia, mental illness, and behavioral disorders. CREB (cAMP-response element-binding protein) represent a nuclear protein that regulates gene transcriptional activity. The primary focus of the review pertains to the exploration of CREB expression and activation within the context of neurodegenerative diseases, specifically in relation to the phosphorylation and dephosphorylation events that occur within the CREB signaling pathway under normal physiological conditions. The findings mentioned have contributed to the elucidation of the regulatory mechanisms governing CREB activity. Additionally, they have provided valuable insights into the potential mediation of diverse biological processes, such as memory consolidation and neuroprotective effects, by various related studies. The promotion of synaptic plasticity and neurodevelopment in the central nervous system through the targeting of CREB proteins has the potential to contribute to the prevention or delay of the onset of neurodegenerative disorders. Multiple drugs have been found to initiate downstream signaling pathways, leading to neuroprotective advantages in both animal model studies and clinical trials. The clinical importance of the cAMP-response element-binding protein (CREB) is examined in this article, encompassing its utility as both a predictive/prognostic marker and a target for therapeutic interventions.

Recent Development of Novel Aminoethyl-Substituted Chalcones as Potential Drug Candidates for the Treatment of Alzheimer's Disease

No drug on the market, as a single entity, participates in different pathways involved in the pathology of Alzheimer's disease. The current study is aimed at the exploration of multifunctional chalcone derivatives which can act on multiple targets involved in Alzheimer's disease. A series of novel aminoethyl-substituted chalcones have been developed using in silico approaches (scaffold morphing, molecular docking, and ADME) and reported synthetic methods. The synthesized analogs were characterized and evaluated biologically using different in vitro assays against AChE, AGEs, and radical formation. Among all compounds, compound PS-10 was found to have potent AChE inhibitory activity (IC50 = 15.3 nM), even more than the standard drug (IC50 = 15.68 nM). Further, the in vivo evaluation of PS-10 against STZ-induced dementia in rats showed memory improvement (Morris Water Maze test) in rats. Also, PS-10 inhibited STZ-induced brain AChE activity and oxidative stress, further strengthening the observed in vitro effects. Further, the molecular dynamic simulation studies displayed the stability of the PS-10 and AChE complex. The novel aminoethyl-substituted chalcones might be considered potential multifunctional anti-Alzheimer's molecules.

Therapeutic potential of NOX inhibitors in neuropsychiatric disorders

RATIONALE

Neuropsychiatric disorders encompass a broad category of medical conditions that include both neurology as well as psychiatry such as major depressive disorder, autism spectrum disorder, bipolar disorder, schizophrenia as well as psychosis.

OBJECTIVE

NADPH-oxidase (NOX), which is the free radical generator, plays a substantial part in oxidative stress in neuropsychiatric disorders. It is thought that elevated oxidative stress as well as neuroinflammation plays a part in the emergence of neuropsychiatric disorders. Including two linked with membranes and four with subunits of cytosol, NOX is a complex of multiple subunits. NOX has been linked to a significant source of reactive oxygen species in the brain. NOX has been shown to control memory processing and neural signaling. However, excessive NOX production has been linked to cardiovascular disorders, CNS degeneration, and neurotoxicity. The increase in NOX leads to the progression of neuropsychiatric disorders.

RESULT

Our review mainly emphasized the characteristics of NOX and its various mechanisms, the modulation of NOX in various neuropsychiatric disorders, and various studies supporting the fact that NOX might be the potential therapeutic target for neuropsychiatric disorders.

CONCLUSION

Here, we summarizes various pharmacological studies involving NOX inhibitors in neuropsychiatric disorders.

Scaffold Morphing and In Silico Design of Potential BACE-1 (β-Secretase) Inhibitors: A Hope for a Newer Dawn in Anti-Alzheimer Therapeutics

Alzheimer's disease (AD) is the prime cause of 65-80% of dementia cases and is caused by plaque and tangle deposition in the brain neurons leading to brain cell degeneration. β-secretase (BACE-1) is a key enzyme responsible for depositing extracellular plaques made of β-amyloid protein. Therefore, efforts are being applied to develop novel BACE-1 enzyme inhibitors to halt plaque build-up. In our study, we analyzed some Elenbecestat analogues (a BACE-1 inhibitor currently in clinical trials) using a structure-based drug design and scaffold morphing approach to achieve a superior therapeutic profile, followed by in silico studies, including molecular docking and pharmacokinetics methodologies. Among all the designed compounds, SB306 and SB12 showed good interactions with the catalytic dyad motifs (Asp228 and Asp32) of the BACE-1 enzyme with drug-likeliness properties and a high degree of thermodynamic stability confirmed by the molecular dynamic and stability of the simulated system indicating the inhibitory nature of the SB306 and SB12 on BACE 1.

Proteomics analysis of plasma from middle-aged adults identifies protein markers of dementia risk in later life

A diverse set of biological processes have been implicated in the pathophysiology of Alzheimer's disease (AD) and related dementias. However, there is limited understanding of the peripheral biological mechanisms relevant in the earliest phases of the disease. Here, we used a large-scale proteomics platform to examine the association of 4877 plasma proteins with 25-year dementia risk in 10,981 middle-aged adults. We found 32 dementia-associated plasma proteins that were involved in proteostasis, immunity, synaptic function, and extracellular matrix organization. We then replicated the association between 15 of these proteins and clinically relevant neurocognitive outcomes in two independent cohorts. We demonstrated that 12 of these 32 dementia-associated proteins were associated with cerebrospinal fluid (CSF) biomarkers of AD, neurodegeneration, or neuroinflammation. We found that eight of these candidate protein markers were abnormally expressed in human postmortem brain tissue from patients with AD, although some of the proteins that were most strongly associated with dementia risk, such as GDF15, were not detected in these brain tissue samples. Using network analyses, we found a protein signature for dementia risk that was characterized by dysregulation of specific immune and proteostasis/autophagy pathways in adults in midlife ~20 years before dementia onset, as well as abnormal coagulation and complement signaling ~10 years before dementia onset. Bidirectional two-sample Mendelian randomization genetically validated nine of our candidate proteins as markers of AD in midlife and inferred causality of SERPINA3 in AD pathogenesis. Last, we prioritized a set of candidate markers for AD and dementia risk prediction in midlife.

TRPM7 kinase activity induces amyloid-β degradation to reverse synaptic and cognitive deficits in mouse models of Alzheimer's disease

Altered abundance or activity of the dual-function transient receptor potential melastatin-like 7 (TRPM7) protein is implicated in neurodegenerative disorders, including Alzheimer's disease (AD). Toxic aggregation of amyloid-β (Aβ) in neurons is implicated in AD pathology. Here, we found that the kinase activity of TRPM7 is important to stimulate the degradation of Aβ. TRPM7 expression was decreased in hippocampal tissue samples from patients with AD and two mouse models of AD (APP/PS1 and 5XFAD). In cultures of hippocampal neurons from mice, overexpression of full-length TRPM7 or of its functional kinase domain M7CK prevented synapse loss induced by exogenous Aβ. In contrast, this neuroprotection was not afforded by overexpression of either the functional ion channel portion alone or a TRPM7 mutant lacking kinase activity. M7CK overexpression in the hippocampus of young and old 5XFAD mice prevented and reversed, respectively, memory deficits, synapse loss, and Aβ plaque accumulation. In both neurons and mice, M7CK interacted with and activated the metalloprotease MMP14 to promote Aβ degradation. Thus, TRPM7 loss in patients with AD may contribute to the associated Aβ pathology.

Overview of blood-brain barrier dysfunction in methamphetamine abuse

Methamphetamine (METH) is one of the psychostimulants most widely abused in the world. METH abuse can lead to severe neurotoxicity. The blood-brain barrier (BBB) is a natural barrier separating the central nervous system (CNS) from the peripheral blood circulation, which can limit or regulate the exchange of toxic substances, molecules, ions, etc., to maintain the homeostasis of CNS. Long-term or high dose abuse of METH can cause structural or functional abnormalities of the BBB and increase the risk of neurodegenerative diseases. In this review, we discussed the mechanisms of METH-induced BBB dysfunction, summarized the risk factors that could exacerbate METH-induced BBB dysfunction, and introduced some potential therapeutic agents. It would provide an important basis and direction for the prevention and treatment of BBB dysfunction induced by METH.

MMP2 rs243866 and rs2285053 Polymorphisms and Alzheimer’s Disease Risk in Slovak Caucasian Population

Alzheimer’s disease (AD) is an age-related neurodegenerative disorder characterised by progressive loss of memory. In the AD brain, matrix metalloproteinases (MMPs) are involved in the disruption of the blood-brain barrier resulting in a neuroinflammatory response. The objective of our investigation was to assess the association of MMP2 rs243866 and rs2285053 polymorphisms with susceptibility to AD, to assess the interaction of MMP2 variants with APOE ε4 risk allele, and to evaluate their influence on the age at disease onset and MoCA score. A total of 215 late-onset AD patients and 373 control subjects from Slovakia were genotyped for MMP2 rs243866 and rs2285053 polymorphisms. The MMP2 association with AD risk and clinical parameters was evaluated by logistic and linear regression analyses. No statistically significant differences in either MMP2 rs243866 and rs2285053 allele or genotype frequencies between AD patients and the control group have been observed (p > 0.05). However, the correlation with clinical findings revealed a higher age at disease onset in MMP2 rs243866 GG carriers in the dominant model as compared to other MMP2 genotype carriers (p = 0.024). Our results suggest that MMP2 rs243866 promoter polymorphism may have an impact on the age at AD onset in the patients.

Induced Pluripotent Stem Cells and Their Applications in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that results in the loss of motor function in the central nervous system (CNS) and ultimately death. The mechanisms underlying ALS pathogenesis have not yet been fully elucidated, and ALS cannot be treated effectively. Most studies have applied animal or single-gene intervention cell lines as ALS disease models, but they cannot accurately reflect the pathological characteristics of ALS. Induced pluripotent stem cells (iPSCs) can be reprogrammed from somatic cells, possessing the ability to self-renew and differentiate into a variety of cells. iPSCs can be obtained from ALS patients with different genotypes and phenotypes, and the genetic background of the donor cells remains unchanged during reprogramming. iPSCs can differentiate into neurons and glial cells related to ALS. Therefore, iPSCs provide an excellent method to evaluate the impact of diseases on ALS patients. Moreover, patient-derived iPSCs are obtained from their own somatic cells, avoiding ethical concerns and posing only a low risk of immune rejection. The iPSC technology creates new hope for ALS treatment. Here, we review recent studies on iPSCs and their applications in disease modeling, drug screening and cell therapy in ALS, with a particular focus on the potential for ALS treatment.

The Exosome-Mediated PI3K/Akt/mTOR Signaling Pathway in Neurological Diseases

As major public health concerns associated with a rapidly growing aging population, neurodegenerative diseases (NDDs) and neurological diseases are important causes of disability and mortality. Neurological diseases affect millions of people worldwide. Recent studies have indicated that apoptosis, inflammation, and oxidative stress are the main players of NDDs and have critical roles in neurodegenerative processes. During the aforementioned inflammatory/apoptotic/oxidative stress procedures, the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway plays a crucial role. Considering the functional and structural aspects of the blood-brain barrier, drug delivery to the central nervous system is relatively challenging. Exosomes are nanoscale membrane-bound carriers that can be secreted by cells and carry several cargoes, including proteins, nucleic acids, lipids, and metabolites. Exosomes significantly take part in the intercellular communications due to their specific features including low immunogenicity, flexibility, and great tissue/cell penetration capabilities. Due to their ability to cross the blood-brain barrier, these nano-sized structures have been introduced as proper vehicles for central nervous system drug delivery by multiple studies. In the present systematic review, we highlight the potential therapeutic effects of exosomes in the context of NDDs and neurological diseases by targeting the PI3K/Akt/mTOR signaling pathway.

RNA regulation of inflammatory responses in glia and its potential as a therapeutic target in central nervous system disorders

A major hallmark of neuroinflammation is the activation of microglia and astrocytes with the induction of inflammatory mediators such as IL-1β, TNF-α, iNOS, and IL-6. Neuroinflammation contributes to disease progression in a plethora of neurological disorders ranging from acute CNS trauma to chronic neurodegenerative disease. Posttranscriptional pathways of mRNA stability and translational efficiency are major drivers for the expression of these inflammatory mediators. A common element in this level of regulation centers around the adenine- and uridine-rich element (ARE) which is present in the 3' untranslated region (UTR) of the mRNAs encoding these inflammatory mediators. (ARE)-binding proteins (AUBPs) such as Human antigen R (HuR), Tristetraprolin (TTP) and KH- type splicing regulatory protein (KSRP) are key nodes for directing these posttranscriptional pathways and either promote (HuR) or suppress (TTP and KSRP) glial production of inflammatory mediators. This review will discuss basic concepts of ARE-mediated RNA regulation and its impact on glial-driven neuroinflammatory diseases. We will discuss strategies to target this novel level of gene regulation for therapeutic effect and review exciting preliminary studies that underscore its potential for treating neurological disorders.

Synthesis and Comprehensive in Vivo Activity Profiling of Olean-12-en-28-ol, 3β-Pentacosanoate in Experimental Autoimmune Encephalomyelitis: A Natural Remyelinating and Anti-Inflammatory Agent

Multiple sclerosis (MS) treatment has received much attention, yet there is still no certain cure. We herein investigate the therapeutic effect of olean-12-en-28-ol, 3β-pentacosanoate (OPCA) on a preclinical model of MS. First, OPCA was synthesized semisynthetically and characterized. Then, the mice with MOG_35-55-induced experimental autoimmune/allergic encephalomyelitis (EAE) were given OPCA along with a reference drug (FTY720). Biochemical, cellular, and molecular analyses were performed in serum and brain tissues to measure anti-inflammatory and neuroprotective responses. OPCA treatment protected EAE-induced changes in mouse brains maintaining blood-brain barrier integrity and preventing inflammation. Moreover, the protein and mRNA levels of MS-related genes such as HLD-DR1, CCL5, TNF-α, IL6, and TGFB1 were significantly reduced in OPCA-treated mouse brains. Notably, the expression of genes, including PLP, MBP, and MAG, involved in the development and structure of myelin was significantly elevated in OPCA-treated EAE. Furthermore, therapeutic OPCA effects included a substantial reduction in pro-inflammatory cytokines in the serum of treated EAE animals. Lastly, following OPCA treatment, the promoter regions for most inflammatory regulators were hypermethylated. These data support that OPCA is a valuable and appealing candidate for human MS treatment since OPCA not only normalizes the pro- and anti-inflammatory immunological bias but also stimulates remyelination in EAE.

Serum matrix metalloproteinase-9 (MMP-9) as a biomarker in paediatric and adult tick-borne encephalitis patients

Matrix metalloproteinases (MMPs) play an important role in central nervous system infections. We analysed the levels of 8 different MMPs in the cerebrospinal fluid (CSF) of 89 adult patients infected with tick-borne encephalitis (TBE) virus and compared them with the levels in a control group. MMP-9 was the only MMP that showed significantly increased CSF levels in TBE patients. Serum MMP-9 levels were subsequently measured in 101 adult TBE patients at various time points during the neurological phase of TBE and at follow-up. In addition, serum MMP-9 was analysed in 37 paediatric TBE patients. Compared with control levels, both paediatric and adult TBE patients had significantly elevated serum MMP-9 levels. In most adult patients, serum MMP-9 levels peaked at hospital admission, with higher serum MMP-9 levels observed in patients with encephalitis than in patients with meningitis. Elevated serum MMP-9 levels were observed throughout hospitalisation but decreased to normal levels at follow-up. Serum MMP-9 levels correlated with clinical course, especially in patients heterozygous for the single-nucleotide polymorphism rs17576 (A/G; Gln279Arg) in the MMP9 gene. The results highlight the importance of MMP-9 in the pathogenesis of TBE and suggest that serum MMP-9 may serve as a promising bioindicator of TBE in both paediatric and adult TBE patients.

Unique Transcriptional Signatures Correlate with Behavioral and Psychological Symptom Domains in Alzheimer's Disease

Despite the significant burden, cost, and worse prognosis of Alzheimer's disease (AD) with behavioral and psychological symptoms of dementia (BPSD), little is known about the molecular causes of these symptoms. Using antemortem assessments of BPSD in AD, we demonstrate that individual BPSD can be grouped into 4 domain factors in our sample: affective, apathy, agitation, and psychosis. Then, we performed a transcriptome-wide analysis for each domain utilizing bulk RNA-seq of post-mortem anterior cingulate cortex (ACC) tissue. Though all 4 domains are associated with a predominantly downregulated pattern of hundreds of differentially expressed genes (DEGs), most DEGs are unique to each domain, with only 22 DEGs being common to all BPSD domains, including TIMP1. Weighted gene co-expression network analysis (WGCNA) yielded multiple transcriptional modules that were shared between BPSD domains or unique to each domain, and NetDecoder was used to analyze context-dependent information flow through the biological network. For the agitation domain, we found that all DEGs and a highly correlated transcriptional module were functionally enriched for ECM-related genes including TIMP1, TAGLN, and FLNA. Another unique transcriptional module also associated with the agitation domain was enriched with genes involved in post-synaptic signaling, including DRD1, PDE1B, CAMK4, and GABRA4. By comparing context-dependent changes in DEGs between cases and control networks, ESR1 and PARK2 were implicated as two high impact genes associated with agitation that mediated significant information flow through the biological network. Overall, our work establishes unique targets for future study of the biological mechanisms of BPSD and resultant drug development.

Transcriptional and epigenetic regulation of microglia in maintenance of brain homeostasis and neurodegeneration

The emerging role of microglia in brain homeostasis, neurodegeneration, and neurodevelopmental disorders has attracted considerable interest. In addition, recent developments in microglial functions and associated pathways have shed new light on their fundamental role in the immunological surveillance of the brain. Understanding the interconnections between microglia, neurons, and non-neuronal cells have opened up additional avenues for research in this evolving field. Furthermore, the study of microglia at the transcriptional and epigenetic levels has enhanced our knowledge of these native brain immune cells. Moreover, exploring various facets of microglia biology will facilitate the early detection, treatment, and management of neurological disorders. Consequently, the present review aimed to provide comprehensive insight on microglia biology and its influence on brain development, homeostasis, management of disease, and highlights microglia as potential therapeutic targets in neurodegenerative and neurodevelopmental diseases.

CD147 and MMPs as key factors in physiological and pathological processes

Cluster of differentiation 147 (CD147) or extracellular matrix metalloproteinase inducer (EMMPRIN) is a transmembrane glycoprotein that induces the synthesis of matrix metalloproteinases (MMPs). MMPs, as zinc-dependent proteases and versatile enzymes, play critical roles in the degradation of the extracellular matrix (ECM) components, cleaving of the receptors of cellular surfaces, signaling molecules, and other precursor proteins, which may lead to attenuation or activation of such targets. CD147 and MMPs play essential roles in physiological and pathological conditions and any disorder in the expression, synthesis, or function of CD147 and MMPs may be associated with various types of disease. In this review, we have focused on the roles of CD147 and MMPs in some major physiological and pathological processes.

Association of the matrix metalloproteinases (MMPs) family gene polymorphisms and the risk of coronavirus disease 2019 (COVID-19); implications of contribution for development of neurological symptoms in the COVID-19 patients

BACKGROUND

Seemingly, the Matrix metalloproteinases (MMPs) play a role in the etiopathogenesis of coronavirus disease 2019 (COVID-19). Here in this study, we determined the association of MMP9 rs3918242, MMP3 rs3025058, and MMP2 rs243865 polymorphisms with the risk of COVID-19, especially in those with neurological syndrome (NS).

METHODS

We enrolled 500 patients with COVID-19 and 500 healthy individuals. To genotype the target SNPs, the Real-time allelic discrimination technique was used. To determine serum levels of MMPs, Enzyme-linked immunosorbent assay (ELISA) was exerted.

RESULTS

The MMP9 gene rs3918242 and MMP3 gene rs3025058 SNP were significantly associated with increased COVID-19 risk and susceptibility to COVID-19 with NS. The serum level of MMP-9 and MMP-3 was significantly higher in COVID-19 cases compared with the healthy controls. Serum MMP-9 and MMP-3 levels were also higher in COVID-19 subjects with NS in comparison to the healthy controls. The polymorphisms in MMP genes were not associated with serum level of MMPs.

CONCLUSION

MMP9 and MMP3 gene polymorphisms increases the susceptibility to COVID-19 as well as COVID-19 with neurologic syndrome, but they probably have no role in the regulation of serum MMP-9 and MMP-3 levels.

Human stem cell-derived ventral midbrain astrocytes exhibit a region-specific secretory profile

This scientific commentary refers to 'Human stem cell-derived astrocytes exhibit region-specific heterogeneity in their secretory profiles', by Clarke et al. (https://doi.org/10.1093/brain/awaa258) in Brain.

Pharmacotherapy Evolution in Alzheimer's Disease: Current Framework and Relevant Directions

Alzheimer's disease (AD), once considered a rare disease, is now the most common form of dementia in the elderly population. Current drugs (cholinesterase inhibitors and glutamate antagonists) are safe but of limited benefit to most patients, offering symptomatic relief without successful cure of the disease. Since the last several decades, there has been a great need for the development of a treatment that might cure the underlying causes of AD and thereby slow its progression in vulnerable individuals. That is why phase I, II, and III studies that act on several fronts, such as cognitive improvement, symptom reduction, and enhancing the basic biology of AD, are imperative to stop the disease. This review discusses current treatment strategies, summarizing the clinical features and pharmacological properties, along with molecular docking analyses of the existing medications.

The role of innate immune system mediators in the development of retinal neurodegeneration in type 2 diabetes mellitus

Purpose. To detect the levels of transform growth factors-β (TGF- β1, TGF- β2, TGF- β3), interferon-ʏ (INF- ʏ), matrix metalloproteinase-9 (MMP-9) and S100B protein in blood serum of patients with type 2 diabetes mellitus (DM) and to reveal the connection of these factors with neurodegenerative changes in the retina. Material and methods. 30 patients, averagely aged 60.3, with type 2 DM and no signs of diabetic retinopathy (DR) (the main group) and 30 healthy individuals (control group) were examined using microperimetry and optical coherence tomography. A sandwich variance estimator of solid phase enzyme-linked immunosorbent assay was used to determine the levels of TGF- β 1, TGF- β2, TGF- β3, INF- ʏ, ММР-9 and S100B protein in blood serum of the subjects examined. Results. The patients with type 2 DM were found to experience an increased level of focal loss of retinal ganglion cells and a drop in the average photosensitivity of the retina. The main group also showed a reliable increase in the level of S100B protein and in the serum level of MMP-9 against the control, but no significant difference between the groups was found in the level of TIMP-1. The level of TGF- β2 was significantly higher in the main group, which also showed a deficiency of TGF- β3. No significant difference was found between the two groups in the levels of TGF- β1 or INF- ʏ. In contrast, a positive correlation was revealed between the levels of S100B, MMP-9 and the volume of focal loss of retinal ganglion cells. Conclusion. Patients with type 2 DM and signs of neurodegeneration of the retina reveal a higher activity of some cytokines and MMP-9. This may indicate an important role of neuroinflammation and dysfunction of the immune system in the retinal neurodegeneration process of DM patients. Further research of other cytokins is required to determine early and more sensitive markers of retinal neurodegeneration.

MMP-12 knockdown prevents secondary brain damage after ischemic stroke in mice

We previously reported that increased expression of matrix metalloproteinase-12 (MMP-12) mediates blood-brain barrier disruption via tight junction protein degradation after focal cerebral ischemia in rats. Currently, we evaluated whether MMP-12 knockdown protects the post-stroke mouse brain and promotes better functional recovery. Adult male mice were injected with negative siRNA or MMP-12 siRNA (intravenous) at 5 min of reperfusion following 1 h transient middle cerebral artery occlusion. MMP-12 knockdown significantly reduced the post-ischemic infarct volume and improved motor and cognitive functional recovery. Mechanistically, MMP-12 knockdown ameliorated degradation of tight junction proteins zonula occludens-1, claudin-5, and occludin after focal ischemia. MMP-12 knockdown also decreased the expression of inflammatory mediators, including monocyte chemoattractant protein-1, tumor necrosis factor-α, and interleukin-6, and the expression of apoptosis marker cleaved caspase-3 after ischemia. Overall, the present study indicates that MMP-12 promotes secondary brain damage after stroke and hence is a promising stroke therapeutic target.

Utility of Matrix Metalloproteinases in the Diagnosis, Monitoring and Prognosis of Ovarian Cancer Patients

Ovarian cancer is one of the most common gynecologic malignancies. It is characterized by a high mortality rate, which is mainly due to the asymptomatic course of the disease. In light of the high mortality rate and increasing morbidity, new diagnostic methods are being explored to enable earlier detection, better monitoring, and improved prognosis. Such diagnostic methods include the assessment of tumor markers in various biological samples. Among the markers currently being investigated, extracellular matrix metalloproteinases (MMPs) are of particular interest. The objective of this article was to compile the existing knowledge of MMPs in ovarian cancer patients and to describe their potential diagnostic utility. Additionally, this article provides an overview of the symptoms, complications, and risk factors associated with ovarian cancer and the role of MMPs in physiology and pathology. Preliminary results indicate that tissue expression and blood and body fluid levels of MMPs may be different in ovarian cancer patients than in healthy women. The expression and concentration of individual MMPs have been shown to be correlated with cancer stage and disease severity. In addition, the preliminary value of some of these enzymes in predicting prognosis is discussed. However, as the amount of data is limited, more studies are needed to fully evaluate the potential function of individual MMPs in ovarian cancer patients. Based on the knowledge gathered for this article, it seems that MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-13, are tentatively the most useful. A thorough evaluation of their utility as modern biomarkers in ovarian cancer requires further investigation.

Characterization of the Toxicological Impact of Heavy Metals on Human Health in Conjunction with Modern Analytical Methods

Increased environmental pollution, urbanization, and a wide variety of anthropogenic activities have led to the release of toxic pollutants into the environment, including heavy metals (HMs). It has been found that increasing concentrations of HMs lead to toxicity, mineral imbalances, and serious diseases, which are occurring more and more frequently. Therefore, testing has become imperative to detect these deficiencies in a timely manner. The detection of traces of HMs, especially toxic ones, in human tissues, various biological fluids, or hair is a complex, high-precision analysis that enables early diagnosis, addressing people under constant stress or exposed to a toxic environment; the test also targets people who have died in suspicious circumstances. Tissue mineral analysis (TMA) determines the concentration of toxic minerals/metals at the intracellular level and can therefore determine correlations between measured concentrations and imbalances in the body. Framing the already-published information on the topic, this review aimed to explore the toxicity of HMs to human health, the harmful effects of their accumulation, the advantages vs. the disadvantages of choosing different biological fluids/tissues/organs necessary for the quantitative measurement of HM in the human body, as well as the choice of the optimal method, correlated with the purpose of the analysis.

Morphological and biomolecular targets in retina and vitreous from Reelin-deficient mice (Reeler): Potential implications for age-related macular degeneration in Alzheimer’s dementia

The neurosensory retina is an outgrowth of the Central Nervous System (CNS), and the eye is considered “a window to the brain.” Reelin glycoprotein is directly involved in neurodevelopment, in synaptic plasticity, learning and memory. Consequently, abnormal Reelin signaling has been associated with brain neurodegeneration but its contributing role in ocular degeneration is still poorly explored. To this aim, experimental procedures were assayed on vitreous or retinas obtained from Reeler mice (knockout for Reelin protein) at different postnatal days (p) p14, p21 and p28. At p28, a significant increase in the expression of Amyloid Precursor Protein (APP) and its amyloidogenic peptide (Aβ1-42 along with truncated tau fragment (i.e., NH2htau)- three pathological hallmarks of Alzheimer’s disease (AD)-were found in Reeler mice when compared to their age-matched wild-type controls. Likewise, several inflammatory mediators, such as Interleukins, or crucial biomarkers of oxidative stress were also found to be upregulated in Reeler mice by using different techniques such as ELLA assay, microchip array or real-time PCR. Taken together, these findings suggest that a dysfunctional Reelin signaling enables the expression of key pathological features which are classically associated with AD neurodegenerative processes. Thus, this work suggests that Reeler mouse might be a suitable animal model to study not only the pathophysiology of developmental processes but also several neurodegenerative diseases, such as AD and Age-related Macular Degeneration (AMD), characterized by accumulation of APP and/or Aβ1-42, NH2htau and inflammatory markers.

Toward a Combination of Biomarkers for Molecular Characterization of Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system associated with chronic inflammation, demyelination, and axonal damage. MS is a highly heterogeneous disease that leads to discrepancies regarding the clinical appearance, progression, and therapy response of patients. Therefore, there is a strong unmet need for clinically relevant biomarkers capable of recapitulating the features of the disease. Experimental autoimmune encephalomyelitis (EAE) is a valuable model for studying the pathophysiology of MS as it recapitulates the main hallmarks of the disease: inflammation, blood-brain barrier (BBB) disruption, gliosis, myelin damage, and repair mechanisms. In this study, we used the EAE-PLP animal model and established a molecular RNA signature for each phase of the disease (onset, peak, remission). We compared variances of expression of known biomarkers by RT-qPCR in the brain and spinal cord of sham and EAE animals monitoring each of the five hallmarks of the disease. Using magnetic cell isolation technology, we isolated microglia and oligodendrocytes of mice of each category, and we compared the RNA expression variations. We identify genes deregulated during a restricted time frame, and we provide insight into the timing and interrelationships of pathological disease processes at the organ and cell levels.

Marine Natural Products from the Russian Pacific as Sources of Drugs for Neurodegenerative Diseases

Neurodegenerative diseases are growing to become one of humanity's biggest health problems, given the number of individuals affected by them. They cause enough mortalities and severe economic impact to rival cancers and infections. With the current diversity of pathophysiological mechanisms involved in neurodegenerative diseases, on the one hand, and scarcity of efficient prevention and treatment strategies, on the other, all possible sources for novel drug discovery must be employed. Marine pharmacology represents a relatively uncharted territory to seek promising compounds, despite the enormous chemodiversity it offers. The current work discusses one vast marine region-the Northwestern or Russian Pacific-as the treasure chest for marine-based drug discovery targeting neurodegenerative diseases. We overview the natural products of neurological properties already discovered from its waters and survey the existing molecular and cellular targets for pharmacological modulation of the disease. We further provide a general assessment of the drug discovery potential of the Russian Pacific in case of its systematic development to tackle neurodegenerative diseases.

Identification of a novel role for matrix metalloproteinase-3 in the modulation of B cell responses in multiple sclerosis

There has been a growing interest in the presence and role of B cell aggregates within the central nervous system of multiple sclerosis patients. However, very little is known about the expression profile of molecules associated with these aggregates and how they might be influencing aggregate development or persistence in the brain. The current study focuses on the effect of matrix metalloproteinase-3, which is associated with B cell aggregates in autopsied multiple sclerosis brain tissue, on B cells. Autopsied brain sections from multiple sclerosis cases and controls were screened for the presence of CD20⁺ B cell aggregates and expression of matrix metalloproteinase-3. Using flow cytometry, enzyme-linked immunosorbent assay and gene array as methods, in vitro studies were conducted using peripheral blood of healthy volunteers to demonstrate the effect of matrix metalloproteinase-3 on B cells. Autopsied brain sections from multiple sclerosis patients containing aggregates of B cells expressed a significantly higher amount of matrix metalloproteinase-3 compared to controls. In vitro experiments demonstrated that matrix metalloproteinase-3 dampened the overall activation status of B cells by downregulating CD69, CD80 and CD86. Furthermore, matrix metalloproteinase-3-treated B cells produced significantly lower amounts of interleukin-6. Gene array data confirmed that matrix metalloproteinase-3 altered the proliferation and survival profiles of B cells. Taken together, out data indicate a role for B cell modulatory properties of matrix metalloproteinase-3.

Neuroprotective effect of phospholipase A2 from Malaysian Naja sumatrana venom against H2O2-induced cell damage and apoptosis

Oxidative stress is one of the factors involved in the pathogenesis of several neurodegenerative diseases. It has been reported that a secretory phospholipase A2 known as A2-EPTX-NSm1a has lower cytotoxicity in neuronal cells compared to its crude Naja sumatrana venom. In this study, A2-EPTX-NSm1a was tested for its neuroprotective activity on human neuroblastoma cells (SH-SY5Y) differentiated into cholinergic neurons against oxidative stress induced by hydrogen peroxide (H2O2). H2O2 treatment alone increased the caspase-3 and caspase-8 activities, whereas pre-treatment with A2-EPTX-NSm1a reduced the activity of these apoptosis-associated proteins. Moreover, A2-EPTX-NSm1a protects the morphology and ultrastructure of differentiated SH-SY5Y cells in the presence of H2O2. Oxidative stress increased the number of small mitochondria. Further evaluation showed the size of mitochondria with a length below 0.25 µm in oxidative stress conditions is higher than the control group, suggesting mitochondria fragmentation. Pre-treatment with A2-EPTX-NSm1a attenuated the number of mitochondria in cells with H2O2 Furthermore, A2-EPTX-NSm1a altered the expression of several neuroprotein biomarkers of GDNF, IL-8, MCP-1, TIMP-1, and TNF-R1 in cells under oxidative stress induced by H2O2. These findings indicate that anti-apoptosis with mitochondria-related protection, anti-inflammatory effect, and promote expression of important markers for cell survival may underlie the neuroprotective effect of A2-EPTX-NSm1a in cholinergic rich human cells under oxidative stress, a vital role in the neuronal disorder.

Optimized Recombinant Expression and Characterization of Collagenase in Bacillus subtilis WB600

Background: The collagenase encoding gene col was cloned into a pP43NMK vector and amplified in Escherichia coli JM109 cells. The shuttle vector pP43NMK was used to sub-clone the col gene to obtain the vector pP43NMK-col for the expression of collagenase in Bacillus subtilis WB600. The enzyme was characterized and the composition of the expression medium and culture conditions were optimized. Methods: The expressed recombinant enzyme was purified by ammonium sulfate, ultrafiltration, and through a nickel column. The purified collagenase had an activity of 9405.54 U/mg. Results: The recombinant enzyme exhibited optimal activity at pH 9.0 and 50 °C. Catalytic efficiency of the recombinant collagenase was inhibited by Fe3+ and Cu2+, but stimulated by Co2+, Ca2+, Zn2+, and Mg2+. The optimal conditions for its growth were at pH 7.0 and 35 °C, using 15 g/L of fructose and 36 g/L of yeast powder and peptone mixture (2:1) at 260 rpm with 11% inoculation. The maximal extracellular activity of the recombinant collagenase reached 2746.7 U/mL after optimization of culture conditions, which was 2.4-fold higher than that before optimization. Conclusions: This study is a first attempt to recombinantly express collagenase in B. subtilis WB600 and optimize its expression conditions, its production conditions, and possible scale-up.

Free radical biology in neurological manifestations: mechanisms to therapeutics interventions

Recent advancements and growing attention about free radicals (ROS) and redox signaling enable the scientific fraternity to consider their involvement in the pathophysiology of inflammatory diseases, metabolic disorders, and neurological defects. Free radicals increase the concentration of reactive oxygen and nitrogen species in the biological system through different endogenous sources and thus increased the overall oxidative stress. An increase in oxidative stress causes cell death through different signaling mechanisms such as mitochondrial impairment, cell-cycle arrest, DNA damage response, inflammation, negative regulation of protein, and lipid peroxidation. Thus, an appropriate balance between free radicals and antioxidants becomes crucial to maintain physiological function. Since the 1brain requires high oxygen for its functioning, it is highly vulnerable to free radical generation and enhanced ROS in the brain adversely affects axonal regeneration and synaptic plasticity, which results in neuronal cell death. In addition, increased ROS in the brain alters various signaling pathways such as apoptosis, autophagy, inflammation and microglial activation, DNA damage response, and cell-cycle arrest, leading to memory and learning defects. Mounting evidence suggests the potential involvement of micro-RNAs, circular-RNAs, natural and dietary compounds, synthetic inhibitors, and heat-shock proteins as therapeutic agents to combat neurological diseases. Herein, we explain the mechanism of free radical generation and its role in mitochondrial, protein, and lipid peroxidation biology. Further, we discuss the negative role of free radicals in synaptic plasticity and axonal regeneration through the modulation of various signaling molecules and also in the involvement of free radicals in various neurological diseases and their potential therapeutic approaches. The primary cause of free radical generation is drug overdosing, industrial air pollution, toxic heavy metals, ionizing radiation, smoking, alcohol, pesticides, and ultraviolet radiation. Excessive generation of free radicals inside the cell R1Q1 increases reactive oxygen and nitrogen species, which causes oxidative damage. An increase in oxidative damage alters different cellular pathways and processes such as mitochondrial impairment, DNA damage response, cell cycle arrest, and inflammatory response, leading to pathogenesis and progression of neurodegenerative disease other neurological defects.

2,4-Diacetylphloroglucinol Reduces Beta-Amyloid Production and Secretion by Regulating ADAM10 and Intracellular Trafficking in Cellular and Animal Models of Alzheimer's Disease

There is currently no effective treatment against Alzheimer’s disease (AD), although many strategies have been applied to reduce beta-amyloid (Aβ) levels. Here, we investigated 2,4-diacetylphloroglucinol (DAPG) effects on Aβ levels and mechanisms of action. DAPG was the most effective phloroglucinol derivative for reducing Aβ levels, without being toxic, in various models including HEK293 cells overexpressing Swedish mutant amyloid precursor protein (APP) (293sw), primary astrocytes isolated from APPsw/PS1dE9 transgenic mice, and after intrahippocampal injection of DAPG in APPsw/PS1dE9 transgenic mice. DAPG-mediated Aβ reduction was associated with increased soluble APPα (sAPPα) levels mediated by a disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) but not ADAM17. ADAM10 inhibition in DAPG-treated cells prevented the effects on sAPPα but only partly on intracellular and secreted Aβ. To identify regulators of sAPPα and Aβ secretion, various inhibitors of intracellular trafficking were administered with DAPG. Brefeldin A (BFA) reversed DAPG-mediated changes in Aβ secretion in 293sw cells, whereas golgicide A (GCA) and BFA were effective in primary astrocytes, indicating a cell type-specific regulation of the trafficking. Moreover, GCA or BFA effects on sAPPα, but not Aβ, levels in primary astrocytes resembled those of ADAM10 inhibition, indicating at least partly independent trafficking pathways for sAPPα and Aβ. In conclusion, DAPG might be a promising drug candidate against AD regulating ADAM10 and intracellular trafficking, but optimizing DAPG ability to cross the BBB will be needed.

Potential Protective Effect of Dl-3-n-butylphthalide on Chronic Cerebral Ischemia Brain Injury

Chronic cerebral ischemia is one of the common ischemic cerebrovascular diseases. Chronic cerebral ischemia can lead to brain dysfunction, and its pathophysiological mechanism involves inflammation, blood-brain barrier destruction, oxidative stress, and other factors. As it is difficult to detect, it is easily overlooked, and it is often only observed following the onset of cognitive dysfunction. At present, there are only a few drugs for its treatment. Dl-3-n-butylphthalide (NBP), a compound extracted from celery seed, may play an important role in protecting against brain damage caused by chronic cerebral ischemia. Therefore, here, we have paid attention to the prevention and treatment of chronic cerebral ischemia with NBP.

Sex-Related Differences of Matrix Metalloproteinases (MMPs): New Perspectives for These Biomarkers in Cardiovascular and Neurological Diseases

It is now established that sex differences occur in clinical manifestation, disease progression, and prognosis for both cardiovascular (CVDs) and central nervous system (CNS) disorders. As such, a great deal of effort is now being put into understanding these differences and turning them into “advantages”: (a) for the discovery of new sex-specific biomarkers and (b) through a review of old biomarkers from the perspective of the “newly” discovered sex/gender medicine. This is also true for matrix metalloproteinases (MMPs), enzymes involved in extracellular matrix (ECM) remodelling, which play a role in both CVDs and CNS disorders. However, most of the studies conducted up to now relegated sex to a mere confounding variable used for statistical model correction rather than a determining factor that can influence MMP levels and, in turn, disease prognosis. Consistently, this approach causes a loss of information that might help clinicians in identifying novel patterns and improve the applicability of MMPs in clinical practice by providing sex-specific threshold values. In this scenario, the current review aims to gather the available knowledge on sex-related differences in MMPs levels in CVDs and CNS conditions, hoping to shed light on their use as sex-specific biomarkers of disease prognosis or progression.