Sulforaphane rescues amyloid-β peptide-mediated decrease in MerTK expression through its anti-inflammatory effect in human THP-1 macrophages

Molecular mechanisms of sulforaphane in Alzheimer's disease: insights from an in-silico study

This study was to identify the molecular pathways that may explain sulforaphane's Alzheimer's disease (AD) benefits using multiple advanced in silico approaches. We found that sulforaphane regulates 45 targets, including TNF, INS, and BCL2. Therefore, it may help treat AD by reducing neuroinflammation, insulin resistance, and apoptosis. The important relationships were co-expression and pathways. 45 targets were linked to the midbrain, metabolite interconversion enzymes, 14q23.3 and 1q31.1 chromosomes, and modified residues. "Amyloid precursor protein catabolic process", "regulation of apoptotic signaling pathway", and "positive regulation of nitric oxide biosynthetic process" were the main pathways, while NFKB1, SP1, RELA, hsa-miR-17-5p, hsa-miR-16-5p, and hsa-miR-26b-5p were transcription factors and miRNAs implicated in sulforaphane In AD treatment, miRNA sponges, dexibuprofen, and sulforaphane may be effective. Furthermore, its unique physicochemical, pharmacokinetic, and biological qualities make sulforaphane an effective AD treatment, including efficient gastrointestinal absorption, drug-like properties, absence of CYP450 enzyme inhibition, not being a substrate for P-glycoprotein, ability to cross the blood-brain barrier, glutathione S-transferase substrate, immunostimulant effects, and antagonistic neurotransmitter effects. Sulforaphane is a promising compound for AD management. Further work is needed to elucidate its therapeutic effects based on our findings, including genes, miRNAs, molecular pathways, and transcription factors.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-024-00267-4.

Anti-Inflammatory Therapeutic Mechanisms of Isothiocyanates: Insights from Sulforaphane

Isothiocyanates (ITCs) belong to a group of natural products that possess a highly reactive electrophilic -N=C=S functional group. They are stored in plants as precursor molecules, glucosinolates, which are processed by the tyrosinase enzyme upon plant tissue damage to release ITCs, along with other products. Isolated from broccoli, sulforaphane is by far the most studied antioxidant ITC, acting primarily through the induction of a transcription factor, the nuclear factor erythroid 2-related factor 2 (Nrf2), which upregulates downstream antioxidant genes/proteins. Paradoxically, sulforaphane, as a pro-oxidant compound, can also increase the levels of reactive oxygen species, a mechanism which is attributed to its anticancer effect. Beyond highlighting the common pro-oxidant and antioxidant effects of sulforaphane, the present paper was designed to assess the diverse anti-inflammatory mechanisms reported to date using a variety of in vitro and in vivo experimental models. Sulforaphane downregulates the expression of pro-inflammatory cytokines, chemokines, adhesion molecules, cycloxyhenase-2, and inducible nitric oxide synthase. The signalling pathways of nuclear factor κB, activator protein 1, sirtuins 1, silent information regulator sirtuin 1 and 3, and microRNAs are among those affected by sulforaphane. These anti-inflammatory actions are sometimes due to direct action via interaction with the sulfhydryl structural moiety of cysteine residues in enzymes/proteins. The following are among the topics discussed in this paper: paradoxical signalling pathways such as the immunosuppressant or immunostimulant mechanisms; crosstalk between the oxidative and inflammatory pathways; and effects dependent on health and disease states.

Disturbed flow impairs MerTK-mediated efferocytosis in aortic endothelial cells during atherosclerosis

Background: MER proto-oncogene tyrosine kinase (MerTK) is a key receptor for efferocytosis, a process for the clearance of apoptotic cells. MerTK is mainly expressed in macrophages and immature dendritic cells. There are very limited reports focused on MerTK biology in aortic endothelial cells (ECs). It remains unclear for the role of blood flow patterns in regulating MerTK-mediated efferocytosis in aortic ECs. This study was designed to investigate whether endothelial MerTK and EC efferocytosis respond to blood flow patterns during atherosclerosis. Methods: Big data analytics, RNA-seq and proteomics combined with our in vitro and in vivo studies were applied to reveal the potential molecular mechanisms. Partial carotid artery ligation combined with AAV-PCSK9 and high fat diet were used to set up acute atherosclerosis in 4 weeks. Results: Our data showed that MerTK is sensitive to blood flow patterns and is inhibited by disturbed flow and oscillatory shear stress in primary human aortic ECs (HAECs). The RNA-seq data in HAECs incubated with apoptotic cells showed that d-flow promotes pro-inflammatory pathway and senescence pathway. Our in vivo data of proteomics and immunostaining showed that, compared with WT group, MerTK-/- aggravates atherosclerosis in d-flow areas through upregulation of endothelial dysfunction markers (e.g. IL-1β, NF-κB, TLR4, MAPK signaling, vWF, VCAM-1 and p22phox) and mitochondrial dysfunction. Interestingly, MerTK-/-induces obvious abnormal endothelial thickening accompanied with decreased endothelial efferocytosis, promoting the development of atherosclerosis. Conclusions: Our data suggests that blood flow patterns play an important role in regulating MerTK-mediated efferocytosis in aortic ECs, revealing a new promising therapeutic strategy with EC efferocytosis restoration to against atherosclerosis.

The protective role of sulforaphane and Homer1a in retinal ischemia-reperfusion injury: Unraveling the neuroprotective interplay

AIMS

Retinal ischemia/reperfusion (I/R) injury is a common pathological basis for various ophthalmic diseases. This study aimed to investigate the potential of sulforaphane (SFN) and Homer1a in regulating cell apoptosis induced by retinal I/R injury and to explore the underlying regulatory mechanism between them.

MATERIALS AND METHODS

In in vivo experiments, C57BL/6J mice and Homer1flox/-/Homer1a+/-/Nestin-Cre+/- mice were used to construct retinal I/R injury models. In vitro experiments utilized the oxygen-glucose deprivation-reperfusion (OGD/R) injury model with primary retinal ganglion cells (RGCs). The effects of Homer1a and SFN on cell apoptosis were observed through pathological analyses, flow cytometry, and visual electrophysiological assessments.

KEY FINDINGS

We discovered that after OGD/R injury, apoptosis of RGCs and intracellular Ca2+ activity significantly increased. However, these changes were reversed upon the addition of SFN, and similar observations were reproduced in in vivo studies. Furthermore, both in vivo and in vitro studies confirmed the upregulation of Homer1a after I/R, which could be further enhanced by the administration of SFN. Moreover, upregulation of Homer1a resulted in a reduction in cell apoptosis and pro-apoptotic proteins, while downregulation of Homer1a had the opposite effect. Flash visual evoked potential, oscillatory potentials, and escape latency measurements in mice supported these findings. Furthermore, the addition of SFN strengthened the neuroprotective effects in the OGD/R + H+ group but weakened them in Homer1flox/-/Homer1a+/-/Nestin-Cre+/- mice.

SIGNIFICANCE

These results indicate that Homer1a plays a significant role in the therapeutic potential of sulforaphane for retinal I/R injury, thereby providing a theoretical basis for clinical treatment.

Dietary glucosinolates derived isothiocyanates: chemical properties, metabolism and their potential in prevention of Alzheimer's disease

Alzheimer's disease (AD) is the most prevalent form of dementia affecting millions of people worldwide. It is a progressive, irreversible, and incurable neurodegenerative disorder that disrupts the synaptic communication between millions of neurons, resulting in neuronal death and functional loss due to the abnormal accumulation of two naturally occurring proteins, amyloid β (Aβ) and tau. According to the 2018 World Alzheimer's Report, there is no single case of an Alzheimer's survivor; even 1 in 3 people die from Alzheimer's disease, and it is a growing epidemic across the globe fruits and vegetables rich in glucosinolates (GLCs), the precursors of isothiocyanates (ITCs), have long been known for their pharmacological properties and recently attracted increased interest for the possible prevention and treatment of neurodegenerative diseases. Epidemiological evidence from systematic research findings and clinical trials suggests that nutritional and functional dietary isothiocyanates interfere with the molecular cascades of Alzheimer's disease pathogenesis and prevent neurons from functional loss. The aim of this review is to explore the role of glucosinolates derived isothiocyanates in various molecular mechanisms involved in the progression of Alzheimer's disease and their potential in the prevention and treatment of Alzheimer's disease. It also covers the chemical diversity of isothiocyanates and their detailed mechanisms of action as reported by various in vitro and in vivo studies. Further clinical studies are necessary to evaluate their pharmacokinetic parameters and effectiveness in humans.

An insight into the TAM system in Alzheimer's disease

The TAM receptors may help delay the progression of Alzheimer's disease (AD). AD is the most common neurodegenerative disease associated with human aging. The TAM receptors, derived from the first letter of its three constituents -Tyro3, Axl, and Mertk, are associated with immune responses, cellular differentiation and migration, and clearance of apoptotic cells and debris, with the two canonical ligands, Growth Arrest Specific 6 (Gas6) and ProS1. Several kinds of research have indicated the participation of the TAM system in AD pathology. Also, the TAMs regulate multiple features of microglia, the significant sensors of disorder in the central nervous system (CNS). In this review, we describe the biology of the TAM receptors and ligands in the CNS. Then, we discuss the relationship between the TAM system and AD, specially focusing on its functional expression in the microglia. Finally, we also summarize some agents that could interfere with the TAM signaling pathways and discuss potential difficulties and strategies for drug development.

Combined metabolic activators improve cognitive functions in Alzheimer's disease patients: a randomised, double-blinded, placebo-controlled phase-II trial

BACKGROUND

Alzheimer's disease (AD) is associated with metabolic abnormalities linked to critical elements of neurodegeneration. We recently administered combined metabolic activators (CMA) to the AD rat model and observed that CMA improves the AD-associated histological parameters in the animals. CMA promotes mitochondrial fatty acid uptake from the cytosol, facilitates fatty acid oxidation in the mitochondria, and alleviates oxidative stress.

METHODS

Here, we designed a randomised, double-blinded, placebo-controlled phase-II clinical trial and studied the effect of CMA administration on the global metabolism of AD patients. One-dose CMA included 12.35 g L-serine (61.75%), 1 g nicotinamide riboside (5%), 2.55 g N-acetyl-L-cysteine (12.75%), and 3.73 g L-carnitine tartrate (18.65%). AD patients received one dose of CMA or placebo daily during the first 28 days and twice daily between day 28 and day 84. The primary endpoint was the difference in the cognitive function and daily living activity scores between the placebo and the treatment arms. The secondary aim of this study was to evaluate the safety and tolerability of CMA. A comprehensive plasma metabolome and proteome analysis was also performed to evaluate the efficacy of the CMA in AD patients.

RESULTS

We showed a significant decrease of AD Assessment Scale-cognitive subscale (ADAS-Cog) score on day 84 vs day 0 (P = 0.00001, 29% improvement) in the CMA group. Moreover, there was a significant decline (P = 0.0073) in ADAS-Cog scores (improvement of cognitive functions) in the CMA compared to the placebo group in patients with higher ADAS-Cog scores. Improved cognitive functions in AD patients were supported by the relevant alterations in the hippocampal volumes and cortical thickness based on imaging analysis. Moreover, the plasma levels of proteins and metabolites associated with NAD + and glutathione metabolism were significantly improved after CMA treatment.

CONCLUSION

Our results indicate that treatment of AD patients with CMA can lead to enhanced cognitive functions and improved clinical parameters associated with phenomics, metabolomics, proteomics and imaging analysis. Trial registration ClinicalTrials.gov NCT04044131 Registered 17 July 2019, https://clinicaltrials.gov/ct2/show/NCT04044131.

Effects of sulforaphane intake on processing speed and negative moods in healthy older adults: Evidence from a randomized controlled trial

Background

Recent studies have reported that sulforaphane (SFN) intake with cognitive training had positive effects on cognitive functions. However, it is still unknown whether SFN intake alone has beneficial effects on cognition as well as mood. We investigated whether a SFN intake intervention improved cognitive performance and mood states in healthy older adults.

Methods

In a 12-week, double-blinded, randomized controlled trial (RCT), we randomly assigned 144 older adults to a SFN group or a placebo group. We asked the participants to take a supplement (SFN or placebo) for 12 weeks. We measured several cognitive functions, mood states, and biomarkers before and after the intervention period.

Results

The SFN group showed improvement in processing speed and a decrease in negative mood compared to the placebo group. In addition, the SFN group exhibited a higher SFN-N-acetyl-L-cysteine (NAC) level compared to the placebo group. However, there were no significant results in other biomarkers of oxidant stress, inflammation, or neural plasticity.

Discussion

These results indicate that nutrition interventions using SFN can have positive effects on cognitive functioning and mood in healthy older adults.

Detection of molecular signatures and pathways shared by Alzheimer's disease and type 2 diabetes

Alzheimer's disease (AD) and type 2 diabetes (T2D) are common in the general elderly population, conferring heavy individual, social, and economic stresses on families and society. Accumulating evidence indicates T2D to be a risk factor for AD. However, the underlying mechanisms for this association are largely unknown. This study aimed to identify the shared molecular signatures between AD and T2D through integrated analysis of temporal cortex gene expression data. Gene Ontology (GO) and pathway enrichment analysis, protein over-representation analysis, protein-protein interaction, DEG-transcription factor interactions, DEG-microRNA interactions, protein-drug interactions, gene-disease association analysis, and protein subcellular localization analysis of the common DEGs were performed. We identified 16 common DEGs between the two datasets, which were mainly enriched in the biological processes of apoptosis, autophagy, inflammation, and hemostasis. We also identified five hub proteins encoded by the DEGs, five central regulatory transcription factors, and six microRNAs. Protein-drug interaction analysis showed C1QB to be associated with different drugs. Gene-disease association analysis revealed that hub genes, SFN and ITGB2, were actively engaged in other diseases. Collectively, these findings provide new insights into shared molecular mechanisms between AD and T2D and provide novel candidate targets for therapeutic intervention.

Beneficial Health Effects of Glucosinolates-Derived Isothiocyanates on Cardiovascular and Neurodegenerative Diseases

Neurodegenerative diseases (NDDs) and cardiovascular diseases (CVDs) are illnesses that affect the nervous system and heart, all of which are vital to the human body. To maintain health of the human body, vegetable diets serve as a preventive approach and particularly Brassica vegetables have been associated with lower risks of chronic diseases, especially NDDs and CVDs. Interestingly, glucosinolates (GLs) and isothiocyanates (ITCs) are phytochemicals that are mostly found in the Cruciferae family and they have been largely documented as antioxidants contributing to both cardio- and neuroprotective effects. The hydrolytic breakdown of GLs into ITCs such as sulforaphane (SFN), phenylethyl ITC (PEITC), moringin (MG), erucin (ER), and allyl ITC (AITC) has been recognized to exert significant effects with regards to cardio- and neuroprotection. From past in vivo and/or in vitro studies, those phytochemicals have displayed the ability to mitigate the adverse effects of reactive oxidation species (ROS), inflammation, and apoptosis, which are the primary causes of CVDs and NDDs. This review focuses on the protective effects of those GL-derived ITCs, featuring their beneficial effects and the mechanisms behind those effects in CVDs and NDDs.

Predicting sulforaphane-induced adverse effects in colon cancer patients via in silico investigation

Colorectal cancer (CRC) is a significant global health burden that ranks as the third most diagnosed and second most common cause of cancer related deaths worldwide. New therapeutic strategies include chemoprevention and use of molecules which could prevent, suppress or reverse CRC progression such as sulforaphane (SFN). However, evidences about its safety in CRC patients are still lacking. The aim of this in silico investigation was to predict SFN-induced adverse effects in CRC patients by computational analysis. The study showed that 334 genes were consistently dysregulated in CRC (223 downregulated and 111 upregulated), while 38 were recognized as significant and might be used as predictive biomarkers for overall survival and metastasis (TCGA, GEO, R studio). Among them, SFN interacted with 86 genes, out of which 11 were marked as significant (correlate with overall prognosis and metastasis). Sulforaphane potentiates the overexpression of TIMP1, AURKA, and CEP55, and promotes inhibition of CRYAB, PLCE1, and MMP28, that might lead to the progression of CRC (CTD). Pathway enrichment analysis revealed that SFN stimulated Transcriptional activation of RUNX2, AURKA activation by TPX2, IL-10 signaling, while inhibited Differentiation of White and Brown Adipocyte process, an underlying pathway which inactivation led to obesity (Cytoscape ClueGo + CluePedia, DAVID). Thus, genome signature of CRC patients could serve as important factor when addressing the risk-to-benefit profile of SFN. Patients with colon cancer and increased expression of TIMP1, CCL20, SPP1, AURKA, CEP55, NEK2, SOX9 and CDK1, or downregulation of CRYAB, PLCE1, MMP28, BMP2 and PLAC8 may not be ideal candidates for SFN chemoprevention.

EDIL3 deficiency ameliorates adverse cardiac remodeling by neutrophil extracellular traps (NET)-mediated macrophage polarization

AIMS

After myocardial infarction (MI), injured cardiomyocytes recruit neutrophils and monocytes/macrophages to myocardium, which in turn initiates inflammatory and reparative cascades, respectively. Either insufficient or excessive inflammation impairs cardiac healing. As an endogenous inhibitor of neutrophil adhesion, EDIL3 plays a crucial role in inflammatory regulation. However, the role of EDIL3 in MI remains obscure. We aimed to define the role of EDIL3 in cardiac remodeling after MI.

METHODS AND RESULTS

Serum EDIL3 levels in MI patients were negatively associated with MI biomarkers. Consistently, WT mice after MI showed low levels of cardiac EDIL3. Compared with WT mice, Edil3-/- mice showed improvement of post-MI adverse remodeling, as they exhibited lower mortality, better cardiac function, shorter scar length and smaller LV cavity. Accordingly, infarcted hearts of Edil3-/- mice contained fewer cellular debris and lower amounts of fibrosis content, with decreased collagen I/III expression and the percentage of α-smooth muscle actin (α-SMA) myofibroblasts. Mechanistically, EDIL3 deficiency did not affect the recruitment of monocytes or T cells, but enhanced neutrophil recruitment and following expansion of pro-inflammatory Mertk-MHC-IIlo-int (myeloid-epithelial-reproductive tyrosine kinase/major histocompatibility complex II) macrophages. The injection of neutrophil-specific C-X-C motif chemokine receptor 2 (CXCR2) antagonist eliminated the differences in macrophage polarization and cardiac function between WT and Edil3-/- mice after MI. Neutrophil extracellular traps (NETs), which were more abundant in the hearts of Edil3-/- mice, contributed to Mertk-MHC-IIlo-int polarization via toll-like receptor 9 pathway. The inhibition of NET formation by treatment of neutrophil elastase inhibitor or DNase I impaired macrophage polarization, increased cellular debris and aggravated cardiac adverse remodeling, thus removed the differences of cardiac function between WT and Edil3-/- mice. Totally, EDIL3 plays an important role in NET-primed macrophage polarization and cardiac remodeling during MI.

CONCLUSION

We not only reveal that EDIL3 deficiency ameliorates adverse cardiac healing via NET-mediated pro-inflammatory macrophage polarization but also discover a new crosstalk between neutrophil and macrophage after MI.

TRANSLATIONAL PERSPECTIVE

We established EDIL3 as a critical regulator of neutrophil recruitment and macrophage polarization during post-MI cardiac remodeling. EDIL3 may be a candidate prognostic biomarker and drug target for cardiovascular diseases. The novel pathways and mechanisms revealed in this study has renewed our understanding of the role of leukocyte adhesion inhibitors in cardiovascular disease. Meanwhile, our study reaffirmed the indispensable role of inflammation in the healing process, thereby prompting the reevaluation of post-MI anti-inflammatory treatments.

Sulforaphane: A review of its therapeutic potentials, advances in its nanodelivery, recent patents, and clinical trials

Traditionally, herbal supplements have shown an exceptional potential of desirability for the prevention of diseases and their treatment. Sulforaphane (SFN), an organosulfur compound belongs to the isothiocyanate (ITC) group and is mainly found naturally in cruciferous vegetables. Several studies have now revealed that SFN possesses broad spectrum of activities and has shown extraordinary potential as antioxidant, antitumor, anti-angiogenic, and anti-inflammatory agent. In addition, SFN is proven to be less toxic, non-oxidizable, and its administration to individuals is well tolerated, making it an effective natural dietary supplement for clinical trials. SFN has shown its ability to be a promising future drug molecule for the management of various diseases mainly due to its potent antioxidant properties. In recent times, several newer drug delivery systems were designed and developed for this potential molecule in order to enhance its bioavailability, stability, and to reduce its side effects. This review focuses to cover numerous data supporting the wide range of pharmacological activities of SFN, its drug-related issues, and approaches to improve its physicochemical and biological properties, including solubility, stability, and bioavailability. Recent patents and the ongoing clinical trials on SFN are also summarized.

Analysis of the role of Purα in the pathogenesis of Alzheimer's disease based on RNA-seq and ChIP-seq

Purine rich element binding protein A (Purα), encoded by the Purα gene, is an important transcriptional regulator that binds to DNA and RNA and is involved in processes such as DNA replication and RNA translation. Purα also plays an important role in the nervous system. To identify the function of Pura, we performed RNA sequence (RNA-seq) analysis of Purɑ-KO mouse hippocampal neuron cell line (HT22) to analyze the effect of Purα deletion on neuronal expression profiles. And combined with ChIP-seq analysis to explore the mechanism of Purα on gene regulation. In the end, totaly 656 differentially expressed genes between HT22 and Purα-KO HT22 cells have been found, which include 7 Alzheimer’s disease (AD)-related genes and 5 Aβ clearance related genes. 47 genes were regulated by Purα directly, the evidence based on CHIP-seq, which include Insr, Mapt, Vldlr, Jag1, etc. Our study provides the important informations of Purα in neuro-development. The possible regulative effects of Purα on AD-related genes consist inthe direct and indirect pathways of Purα in the pathogenesis of AD.

MerTK inhibits the activation of the NLRP3 inflammasome after subarachnoid hemorrhage by inducing autophagy

The NLR family pyrin domain-containing 3 (NLRP3) multiprotein complex is associated with neuroinflammation and poor prognosis after subarachnoid hemorrhage (SAH). Accumulating evidence shows that Mer tyrosine kinase (MerTK) alleviates inflammatory responses via a negative feedback mechanism. However, the contribution and function of MerTK in SAH remain to be determined. In this study, we explored the role of MerTK during microglial NLRP3 inflammasome activation and evaluated its contribution to the outcome of SAH in mice. Activating MerTK with growth arrest-specific 6 (Gas6) alleviated brain edema, neuronal degeneration and neurological deficits after SAH by regulating neuroinflammation. Gas6 did not change the mRNA levels of Nlrp3 or Casp1 but decreased the protein expression of NLRP3, cleaved caspase1 (p20), interleukin-1β and interleukin-18. Furthermore, Gas6 increased the expression of Beclin1, the ratio of LC3-II/LC3-I and the level of autophagic flux. Inhibiting autophagy with 3-MA reversed the inhibition of NLRP3 inflammasome activation and diminished the neuroprotective effects of Gas6. Thus, MerTK activation may exert protective effects by limiting neuroinflammation and promoting neurological recovery after SAH via autophagy induction.

Early onset senescence and cognitive impairment in a murine model of repeated mTBI

Mild traumatic brain injury (mTBI) results in broad neurological symptoms and an increased risk of being diagnosed with a neurodegenerative disease later in life. While the immediate oxidative stress response and post-mortem pathology of the injured brain has been well studied, it remains unclear how early pathogenic changes may drive persistent symptoms and confer susceptibility to neurodegeneration. In this study we have used a mouse model of repeated mTBI (rmTBI) to identify early gene expression changes at 24 h or 7 days post-injury (7 dpi). At 24 h post-injury, gene expression of rmTBI mice shows activation of the DNA damage response (DDR) towards double strand DNA breaks, altered calcium and cell–cell signalling, and inhibition of cell death pathways. By 7 dpi, rmTBI mice had a gene expression signature consistent with induction of cellular senescence, activation of neurodegenerative processes, and inhibition of the DDR. At both timepoints gliosis, microgliosis, and axonal damage were evident in the absence of any gross lesion, and by 7 dpi rmTBI also mice had elevated levels of IL1β, p21, 53BP1, DNA2, and p53, supportive of DNA damage-induced cellular senescence. These gene expression changes reflect establishment of processes usually linked to brain aging and suggests that cellular senescence occurs early and most likely prior to the accumulation of toxic proteins. These molecular changes were accompanied by spatial learning and memory deficits in the Morris water maze. To conclude, we have identified DNA damage-induced cellular senescence as a repercussion of repeated mild traumatic brain injury which correlates with cognitive impairment. Pathways involved in senescence may represent viable treatment targets of post-concussive syndrome. Senescence has been proposed to promote neurodegeneration and appears as an effective target to prevent long-term complications of mTBI, such as chronic traumatic encephalopathy and other related neurodegenerative pathologies.

Pre-Clinical Neuroprotective Evidences and Plausible Mechanisms of Sulforaphane in Alzheimer's Disease

Sulforaphane, a potent dietary bioactive agent obtainable from cruciferous vegetables, has been extensively studied for its effects in disease prevention and therapy. Sulforaphane potently induces transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated expression of detoxification, anti-oxidation, and immune system-modulating enzymes, and possibly acts as an anti-carcinogenic agent. Several clinical trials are in progress to study the effect of diverse types of cruciferous vegetables and sulforaphane on prostate cancer, breast cancer, lung cancer, atopic asthmatics, skin aging, dermatitis, obesity, etc. Recently, the protective effects of sulforaphane on brain health were also considerably studied, where the studies have further extended to several neurological diseases, including Alzheimer’s disease (AD), Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, multiple sclerosis, autism spectrum disorder, and schizophrenia. Animal and cell studies that employ sulforaphane against memory impairment and AD-related pre-clinical biomarkers on amyloid-β, tau, inflammation, oxidative stress, and neurodegeneration are summarized, and plausible neuroprotective mechanisms of sulforaphane to help prevent AD are discussed. The increase in pre-clinical evidences consistently suggests that sulforaphane has a multi-faceted neuroprotective effect on AD pathophysiology. The anti-AD-like evidence of sulforaphane seen in cells and animals indicates the need to pursue sulforaphane research for relevant biomarkers in AD pre-symptomatic populations.

Efficacy of Sulforaphane in Neurodegenerative Diseases

Sulforaphane (SFN) is a phytocompound belonging to the isothiocyanate family. Although it was also found in seeds and mature plants, SFN is mainly present in sprouts of many cruciferous vegetables, including cabbage, broccoli, cauliflower, and Brussels sprouts. SFN is produced by the conversion of glucoraphanin through the enzyme myrosinase, which leads to the formation of this isothiocyanate. SFN is especially characterized by antioxidant, anti-inflammatory, and anti-apoptotic properties, and for this reason, it aroused the interest of researchers. The aim of this review is to summarize the experimental studies present on Pubmed that report the efficacy of SFN in the treatment of neurodegenerative disease, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and multiple sclerosis (MS). Therefore, thanks to its beneficial effects, SFN could be useful as a supplement to counteracting neurodegenerative diseases.

Mild heat combined with lactic acid fermentation: a novel approach for enhancing sulforaphane yield in broccoli puree

This study evaluated for the first time the feasibility of mild preheating treatment of broccoli florets combined with lactic acid bacteria fermentation for enhancing sulforaphane yield in broccoli puree. The optimum preheating condition for in-pack processing of broccoli florets was 3 min treatment at 65 °C increasing sulforaphane yield in broccoli puree by ∼5 times compared to untreated broccoli. Preheating of broccoli florets in-pack (65 °C per 3 min) combined with lactic acid bacteria fermentation further enhanced the sulforaphane content by ∼16 times compared to untreated broccoli. The sulforaphane content of the preheated-fermented puree remained stable (∼94% retention) for two weeks at 4 °C. The results indicate that a combination of judicious heat treatment of broccoli florets with lactic acid bacteria fermentation enables production of safe and high sulforaphane content broccoli products with potential health benefits.

Sulforaphane mitigates mast cell-mediated allergic inflammatory reactions in in silico simulation and in vitro models

Objectives: Sulforaphane, a major ingredient isolated from Brassica oleracea var. italica (broccoli), is known to exhibit anti-inflammatory, anti-cancer, and anti-diabetic effects. In this study, we employed an in vitro model of phorbol 12-myristate 13-acetate and a23187 (PMACI)-stimulated human mast cells (HMC-1 cells) to investigate the anti-allergic inflammatory effects and mechanisms of sulforaphane and Brassica oleracea var. italica extracts.Methods: Cytokine levels were measured by ELISA and quantitative real-time-PCR methods. Caspase-1 activity was determined by caspase-1 assay. Binding mode of sulforaphane within caspase-1 was determined by molecular docking simulation. Protein expression was determined by Western blotting.Results: Water extract of Brassica oleracea var. italica (WE) significantly reduced thymic stromal lymphopoietin (TSLP) secretion and caspase-1 activity on activated HMC-1 cells. In the molecular docking simulation and in vitro caspase-1 assays, sulforaphane regulated caspase-1 activity by docking with the identical binding site of caspase-1. Sulforaphane significantly inhibited the levels of inflammatory mediators including TSLP, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 in a dose-dependent manner. Immunoblotting experiments revealed that sulforaphane and WE reduced translocation of NF-κBp65 into the nucleus and phosphorylation of IκBα in the cytosol. Furthermore, phosphorylation of mitogen-activated protein kinases (MAPK) was down-regulated by treatment with sulforaphane or WE.Conclusion: Our findings suggest that sulforaphane and WE have anti-allergic inflammatory effects by intercepting caspase-1/NF-κB/MAPKs signaling pathways.

Sulforaphane Attenuates Aβ Oligomers Mediated Decrease in Phagocytic Activity of Microglial Cells

Microglia are the brain mononuclear phagocytes which plays a key role in neurodegenerative diseases, like Alzheimer's. Till date, microglia have been explored mostly for their neuro-inflammatory functions. Recent studies have shifted their focus towards less explored functions which involve non-autonomous clearance of protein aggregates. However, these functions are significantly affected by aging and neurodegeneration. In Alzheimer's disease (AD), microglia have been reported to clear amyloid beta (Aβ) deposits via phagocytosis or release various pro-inflammatory cytokines. Whether microglia could be beneficial or detrimental to the brain, it all depends upon the type and strength of stimulus. So, if their beneficial properties could be selectively harnessed without activating pro-inflammatory response, a potential therapeutic strategy could be developed to check the formation of protein aggregates like Aβ. In the present study, we have checked the effect of toxic amyloid beta oligomers (Aβo) on the microglial phagocytic activity. Our findings revealed that at lower concentrations, Aβo are not toxic to the cells and they can survive even with longer exposures but with decreased phagocytic activity. However, at higher concentrations Aβo become toxic and resulted in modulation of various genes which regulates microglial phagocytic activity. Sulforaphane (SFN) treatment has shown to induce the phagocytic activity of Aβo treated microglial cells. In addition, low dose Aβo and SFN treatment have not shown modulation in the levels of pro-inflammatory mediators of microglia. Taken together, these findings suggest that SFN treatment may ameliorate the Aβo mediated decrease in microglial phagocytic activity.

The Glucosinolates: A Sulphur Glucoside Family of Mustard Anti-Tumour and Antimicrobial Phytochemicals of Potential Therapeutic Application

This study reviewed aspects of the biology of two members of the glucosinolate family, namely sinigrin and glucoraphanin and their anti-tumour and antimicrobial properties. Sinigrin and glucoraphanin are converted by the β-sulphoglucosidase myrosinase or the gut microbiota into their bioactive forms, allyl isothiocyanate (AITC) and sulphoraphanin (SFN) which constitute part of a sophisticated defence system plants developed over several hundred million years of evolution to protect them from parasitic attack from aphids, ticks, bacteria or nematodes. Delivery of these components from consumption of cruciferous vegetables rich in the glucosinolates also delivers many other members of the glucosinolate family so the dietary AITCs and SFN do not act in isolation. In vitro experiments with purified AITC and SFN have demonstrated their therapeutic utility as antimicrobials against a range of clinically important bacteria and fungi. AITC and SFN are as potent as Vancomycin in the treatment of bacteria listed by the World Health Organisation as antibiotic-resistant “priority pathogens” and also act as anti-cancer agents through the induction of phase II antioxidant enzymes which inactivate potential carcinogens. Glucosinolates may be useful in the treatment of biofilms formed on medical implants and catheters by problematic pathogenic bacteria such as Pseudomonas aeruginosa and Staphylococcus aureus and are potent antimicrobials against a range of clinically important bacteria and fungi. The glucosinolates have also been applied in the prevention of bacterial and fungal spoilage of food products in advanced atmospheric packaging technology which improves the shelf-life of these products.

Sulforaphane - role in aging and neurodegeneration

In the last several years, numerous molecules derived from plants and vegetables have been tested for their antioxidant, anti-inflammatory, and anti-aging properties. One of them is sulforaphane (SFN), an isothiocyanate present in cruciferous vegetables. SFN activates the antioxidant and anti-inflammatory responses by inducing Nrf2 pathway and inhibiting NF-κB. It also has an epigenetic effect by inhibiting HDAC and DNA methyltransferases and modifies mitochondrial dynamics. Moreover, SFN preserves proteome homeostasis (proteostasis) by activating the proteasome, which has been shown to lead to increased cellular lifespan and prevent neurodegeneration. In this review, we describe some of the molecular and physical characteristics of SFN, its mechanisms of action, and the effects that SFN treatment induces in order to discuss its relevance as a "miraculous" drug to prevent aging and neurodegeneration.